94 results on '"Burger KN"'
Search Results
2. Further data supporting that paclitaxel-associated acute pain syndrome is associated with development of peripheral neuropathy: North Central Cancer Treatment Group trial N08C1.
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Reeves BN, Dakhil SR, Sloan JA, Wolf SL, Burger KN, Kamal A, Le-Lindqwister NA, Soori GS, Jaslowski AJ, Kelaghan J, Novotny PJ, Lachance DH, Loprinzi CL, Reeves, Brandi N, Dakhil, Shaker R, Sloan, Jeff A, Wolf, Sherry L, Burger, Kelli N, Kamal, Arif, and Le-Lindqwister, Nguyet A
- Abstract
Background: Paclitaxel causes an acute pain syndrome (P-APS), occurring within days after each dose and usually abating within days. Paclitaxel also causes a more classic peripheral neuropathy, which steadily increases in severity with increasing paclitaxel total doses. Little detail is available regarding the natural history of these 2 syndromes, or any relationship between them, although a recent publication does provide natural history data about weekly paclitaxel, supporting an association between the severity of P-APS and eventual peripheral neuropathy symptoms.Methods: Patients entering this study were about to receive paclitaxel and carboplatin every 3 weeks. Daily questionnaires were completed for the first week after every chemotherapy dose, and European Organization for Research and Treatment of Cancer, Quality of Life Questionnaire, Chemotherapy-Induced Peripheral Neuropathy 20-item instruments were completed weekly.Results: The P-APS severity peaked on day 4 after the initial chemotherapy dose, with 12%, 29%, 23%, and 36% of patients having maximal pain scores of 0, 1 to 4, 5 or 6, or 7 to 10 during the first week after the first dose of therapy, respectively. Patients with P-APS scores of 0 to 4 with the first dose of chemotherapy had less eventual sensory neuropathy than did patients with P-APS scores of 5 to 10 (P = 0.001). With regard to the more peripheral neuropathy, sensory neuropathy was more problematic than was either motor or autonomic neuropathy. Numbness and tingling were more common components of the sensory neuropathy than was pain.Conclusions: Patients with worse P-APS severities appear to have more eventual chemotherapy-induced peripheral neuropathy. This provides support for the concept that P-APS is a form of nerve pathology. [ABSTRACT FROM AUTHOR]- Published
- 2012
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3. Natural history of paclitaxel-associated acute pain syndrome: prospective cohort study NCCTG N08C1.
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Loprinzi CL, Reeves BN, Dakhil SR, Sloan JA, Wolf SL, Burger KN, Kamal A, Le-Lindqwister NA, Soori GS, Jaslowski AJ, Novotny PJ, Lachance DH, Loprinzi, Charles L, Reeves, Brandi N, Dakhil, Shaker R, Sloan, Jeff A, Wolf, Sherry L, Burger, Kelli N, Kamal, Arif, and Le-Lindqwister, Nguyet A
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- 2011
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4. Outcomes of patients with reduced exercise capacity at time of exercise echocardiography.
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McCully RB, Roger VL, Ommen SR, Mahoney DW, Burger KN, Freeman WK, Pellikka PA, McCully, Robert B, Roger, Veronique L, Ommen, Steve R, Mahoney, Douglas W, Burger, Kelli N, Freeman, William K, and Pellikka, Patricia A
- Abstract
Objective: To characterize the prognostic implications of exercise echocardiography in patients who have reduced exercise capacity at the time of testing.Patients and Methods: We examined the outcomes of 941 patients at the Mayo Clinic in Rochester, Minn, between January 1, 1990, and December 31, 1995, who had reduced exercise capacity on exercise echocardiography (women, <5 metabolic equivalents; men, <7 metabolic equivalents) and evaluated the potential association between clinical, electrocardiographic, and echocardiographic variables and outcomes for patients with normal vs abnormal exercise echocardiograms. We used variables of independent prognostic value to estimate cardiac risk.Results: For patients with normal exercise echocardiograms (n=282), the rate of cardiac death or nonfatal myocardial infarction was 09% per person-year of follow-up, and previous coronary revascularization was the only predictor of the time to cardiac event. For patients with abnormal exercise echocardiograms (n=659), the cardiac event rate was 4.4%. Independent predictors of outcome were exercise left ventricular (LV) ejection fraction (risk ratio, 1.44 per 10% decrement; 95% confidence interval, 1.2-1.7; P<.001) and an increase or no change in LV end-systolic size in response to exercise (risk ratio, 2.22; 95% confidence interval, 1.2-4.1; P=.01).Conclusion: Exercise echocardiographic findings have important prognostic implications for patients who have reduced exercise capacity on testing. Echocardiographic descriptors of LV systolic function and dysfunction obtained immediately after exercise can be used to stratify cardiac risk of patients who do not achieve a level of exercise ordinarily considered to be of "diagnostic" value. [ABSTRACT FROM AUTHOR]- Published
- 2004
5. Outcome after abnormal exercise echocardiography for patients with good exercise capacity: prognostic importance of the extent and severity of exercise-related left ventricular dysfunction.
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McCully RB, Roger VL, Mahoney DW, Burger KN, Click RL, Seward JB, Pellikka PA, McCully, Robert B, Roger, Veronique L, Mahoney, Douglas W, Burger, Kelli N, Click, Roger L, Seward, James B, and Pellikka, Patricia A
- Abstract
Objectives: We sought to define the prognostic implications of the extent and severity of exercise echocardiographic abnormalities in patients with good exercise capacity. BACKGROUND; The exercise capacity of patients with known or suspected coronary artery disease (CAD) is of prognostic importance, as is the extent of exercise-related left ventricular (LV) hypoperfusion or dysfunction.Methods: We examined the outcomes of 1,874 patients with known or suspected CAD (mean age 64 +/- 10 years, 64% men) who had good exercise capacity (> or = 5 metabolic equivalents [METs] for women, > or = 7 METs for men) but abnormal exercise echocardiograms and analyzed the potential association between clinical, exercise and echocardiographic variables and subsequent cardiac events.Results: Multivariate predictors of time to cardiac death or nonfatal myocardial infarction (MI) were diabetes mellitus (risk ratio [RR] 1.88; 95% confidence interval [CI] 1.2 to 3.0), history of MI (RR 2.44; 95% CI 1.6 to 3.6) and an increase or no change in LV end-systolic size in response to exercise (RR 1.61; 95% CI 1.1 to 2.5). Using echocardiographic variables that were of incremental prognostic value, we were able to stratify the cardiac risk of the study population; cardiac death or nonfatal MI rate per person-year of follow-up was 1.6% for patients who had a decrease in LV end-systolic size in response to exercise (n = 1,330) and 1.2% for patients who did not have any severely abnormal LV segments immediately after exercise (n = 868).Conclusions: In patients with good exercise capacity, echocardiographic descriptors of the extent and severity of exercise-related LV dysfunction were of independent and incremental prognostic value. Stratification of patients into low- and higher risk subgroups was possible using these exercise echocardiographic characteristics. [ABSTRACT FROM AUTHOR]- Published
- 2002
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6. Blood Plasma Methylated DNA Markers in the Detection of Lymphoma: Discovery, Validation, and Clinical Pilot.
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Witzig TE, Taylor WR, Mahoney DW, Bamlet WR, Foote PH, Burger KN, Doering KA, Devens ME, Arndt JR, O'Connell MC, Berger CK, Novak AJ, Cerhan JR, Hennek J, Katerov S, Allawi HT, Jevremovic D, Dao LN, Graham RP, and Kisiel JB
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Lymphoma is one of the leading causes of cancer and cancer deaths and yet has not been amenable to population screening. The role of methylated DNA markers (MDMs) in the detection of lymphoma has not been extensively studied. We aimed to discover, validate, and test tissue-derived MDMs of lymphoma in archival plasma specimens. Reduced representation bisulfite sequencing (RRBS) was performed on a discovery set of frozen tissues. MDMs identified were converted to methylation-specific PCR assays and validated on independent formalin-fixed, paraffin-embedded (FFPE) tissues. Target enrichment long-probe quantitative-amplified signal (TELQAS) assays were developed and assayed in plasma-extracted, bisulfite-converted DNA from independent treatment-naïve lymphoma patients and healthy controls. Prediction of cancer status was modeled using random forest model with in silico cross-validation. After discovery and validation in tissue, 16 TELQAS assays (ZNF503, VWA5B1, HOXA9, GABRG3, ITGA5, MAX.chr17.7190, BNC1, CDK20, MAX.chr4.4069, TPBG, DNAH14, SYT6, CACNG8, FAM110B, ADRA1D, and NRN1) were selected for testing in plasma. These detected 78% (95% CI, 74%-82%) of lymphoma cases at 90% specificity. Excluding marginal zone and T-cell lymphomas, sensitivity increased to 84% (80%-88%). MDMs in plasma show promise to detect lymphoma and are candidates for inclusion in multi-cancer detection studies., (© 2024 The Author(s). American Journal of Hematology published by Wiley Periodicals LLC.)
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- 2024
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7. Multimodal pancreatic cancer detection using methylated DNA biomarkers in pancreatic juice and plasma CA 19-9: A prospective multicenter study.
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Engels MML, Berger CK, Mahoney DW, Hoogenboom SA, Sarwal D, Klatte DCF, De La Fuente J, Gandhi S, Taylor WR, Foote PH, Doering KA, Delgado AM, Burger KN, Abu Dayyeh BK, Bofill-Garcia A, Brahmbhatt B, Chandrasekhara V, Gleeson FC, Gomez V, Kumbhari V, Law RJ, Lukens FJ, Raimondo M, Rajan E, Storm AC, Vargas Valls EJ, van Hooft JE, Wallace MB, Kisiel JB, and Majumder S
- Abstract
Background and Aims: In previous studies methylated DNA markers (MDMs) have been identified in pancreatic juice (PJ) for detecting pancreatic ductal adenocarcinoma (PDAC). In this prospective multicenter study, the sensitivity and specificity characteristics of this panel of PJ-MDMs was evaluated standalone and in combination with plasma CA 19-9., Methods: Paired PJ and plasma were assayed from 88 biopsy-proven treatment naïve PDAC cases and 134 controls (normal pancreas: 53, chronic pancreatitis (CP): 23, intraductal papillary mucinous neoplasm (IPMN): 58). Bisulfite-converted DNA from buffered PJ was analyzed using long-probe quantitative amplified signal assay targeting 14 MDMs (NDRG4, BMP3, TBX15, C13orf18, PRKCB, CLEC11A, CD1D, ELMO1, IGF2BP1, RYR2, ADCY1, FER1L4, EMX1, and LRRC4) and a reference gene (methylated B3GALT6). Logistic regression was used to fit the previously identified 3-MDM PJ panel (FER1L4, C13orf18 and BMP3). Discrimination accuracy was summarized using area under the receiver operating characteristic curve (AUROC) with corresponding 95% confidence intervals., Results: Methylated FER1L4 had the highest individual AUROC of 0.83 (95% CI: 0.78-0.89). The AUROC for the 3-MDM PJ + Plasma CA 19-9 model (0.95 (0.92-0.98))) was higher than both the 3-MDM PJ panel (0.87 (0.82-0.92)) and plasma CA 19-9 alone ((0.91 (0.87-0.96) (p=0.0002 and 0.0135, respectively). At a specificity of 88% (95% CI: 81-93%), the sensitivity of this model was 89% (80-94%) for all PDAC stages and 83% (64-94%) for stage I/II PDAC., Conclusion: A panel combining PJ-MDMs and plasma CA19-9 discriminates PDAC from both healthy and disease control groups with high accuracy. This provides support for combining pancreatic juice and blood-based biomarkers for enhancing diagnostic sensitivity and successful early PDAC detection., (Copyright © 2024. Published by Elsevier Inc.)
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- 2024
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8. Methylated DNA Markers in Voided Urine for the Identification of Clinically Significant Prostate Cancer.
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Shah P, Taylor WR, Negaard BJ, Gochanour BR, Mahoney DW, Then SS, Devens ME, Foote PH, Doering KA, Burger KN, Nikolai B, Kaiser MW, Allawi HT, Cheville JC, Kisiel JB, and Gettman MT
- Abstract
Introduction: Non-invasive assays are needed to better discriminate patients with prostate cancer (PCa) to avoid over-treatment of indolent disease. We analyzed 14 methylated DNA markers (MDMs) from urine samples of patients with biopsy-proven PCa relative to healthy controls and further studied discrimination of clinically significant PCa (csPCa) from healthy controls and Gleason 6 cancers., Methods: To evaluate the panel, urine from 24 healthy male volunteers with no clinical suspicion for PCa and 24 men with biopsy-confirmed disease across all Gleason scores was collected. Blinded to clinical status, DNA from the supernatant was analyzed for methylation signal within specific DNA sequences across 14 genes ( HES5 , ZNF655 , ITPRIPL1 , MAX.chr3.6187 , SLCO3A1 , CHST11 , SERPINB9 , WNT3A , KCNB2 , GAS6 , AKR1B1 , MAX.chr3.8028 , GRASP , ST6GALNAC2 ) by target enrichment long-probe quantitative-amplified signal assays., Results: Utilizing an overall specificity cut-off of 100% for discriminating normal controls from PCa cases across the MDM panel resulted in 71% sensitivity (95% CI: 49-87%) for PCa detection (4/7 Gleason 6, 8/12 Gleason 7, 5/5 Gleason 8+) and 76% (50-92%) for csPCa (Gleason ≥ 7). At 100% specificity for controls and Gleason 6 patients combined, MDM panel sensitivity was 59% (33-81%) for csPCa (5/12 Gleason 7, 5/5 Gleason 8+)., Conclusions: MDMs assayed in urine offer high sensitivity and specificity for detection of clinically significant prostate cancer. Prospective evaluation is necessary to estimate discrimination of patients as first-line screening and as an adjunct to prostate-specific antigen (PSA) testing.
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- 2024
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9. An investigation of plasma cell-free RNA for the detection of colorectal cancer: From transcriptome marker selection to targeted validation.
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Northrop-Albrecht EJ, Wu CW, Berger CK, Taylor WR, Foote PH, Doering KA, Gonser AM, Bhagwate A, Sun Z, Mahoney DW, Burger KN, Boardman LA, and Kisiel JB
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- Humans, Male, Female, Middle Aged, Aged, Transcriptome, Early Detection of Cancer methods, Gene Expression Regulation, Neoplastic, Sequence Analysis, RNA methods, Case-Control Studies, Colorectal Neoplasms genetics, Colorectal Neoplasms diagnosis, Colorectal Neoplasms blood, Biomarkers, Tumor genetics, Biomarkers, Tumor blood, Cell-Free Nucleic Acids genetics, Cell-Free Nucleic Acids blood
- Abstract
Regular screening for colorectal cancer (CRC) is critical for early detection and long-term survival. Despite the current screening options available and advancements in therapies there will be around 53,000 CRC related deaths this year. There is great interest in non-invasive alternatives such as plasma cell-free RNA (cfRNA) for diagnostic, prognostic, and predictive applications. In the current study, our aim was to identify and validate potential cfRNA candidates to improve early CRC diagnosis. In phase 1 (n = 49; 25 controls, 24 cancers), discovery total RNA sequencing was performed. Select exons underwent validation in phase 2 (n = 73; 35 controls, 29 cancers, 9 adenomas) using targeted capture sequencing (n = 10,371 probes). In phase 3 (n = 57; 30 controls, 27 cancers), RT-qPCR was performed on previously identified candidates (n = 99). There were 895 exons that were differentially expressed (325 upregulated, 570 downregulated) among cancers versus controls. In phases 2 and 3, fewer markers were validated than expected in independent sets of patients, most of which were from previously published literature (FGA, FGB, GPR107, CDH3, and RP23AP7). In summary, we optimized laboratory processes and data analysis strategies which can serve as methodological framework for future plasma RNA studies beyond just the scope of CRC detection. Additionally, further exploration is needed in order to determine if the few cfRNA candidates identified in this study have clinical utility for early CRC detection. Over time, advancements in technologies, data analysis, and RNA preservation methods at time of collection may improve the biological and technical reproducibility of cfRNA biomarkers and enhance the feasibility of RNA-based liquid biopsies., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests: Ms Berger, Messrs Taylor & Mahoney, and Dr. Kisiel are inventors of Mayo Clinic intellectual property licensed to Exact Sciences (Madison, WI) and may receive royalties, paid to Mayo Clinic. John Kisiel receives funding from a sponsored research agreement between Mayo Clinic and Exact Sciences. Because of the terms of the Sponsored Research Contract and Intellectual Property Development Agreement between Mayo Clinic and Exact Sciences, we have restrictions on sharing raw sequencing data publicly., (Copyright: © 2024 Northrop-Albrecht et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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10. Plasma Assay of Cell-Free Methylated DNA Markers of Colorectal Cancer: A Tumor-Agnostic Approach to Monitor Recurrence and Response to Anticancer Therapies.
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Zhu M, Taylor WR, Mahoney DW, Then SS, Berger CK, Burger KN, Gonser AM, Doering KA, Xie H, Foote PH, Kaiser MW, Allawi HT, Hubbard JM, and Kisiel JB
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Background: Radiographic surveillance of colorectal cancer (CRC) after curative-intent therapy is costly and unreliable. Methylated DNA markers (MDMs) detected primary CRC and metastatic recurrence with high sensitivity and specificity in cross-sectional studies. This study evaluated using serial MDMs to detect recurrence and monitor the treatment response to anti-cancer therapies., Methods: A nested case-control study was drawn from a prospective cohort of patients with CRC who completed curative-intent therapy for CRC of all stages. Plasma MDMs were assayed vis target enrichment long-probe quantitative-amplified signal assays, normalized to B3GALT6 , and analyzed in combination with serum carcinoembryonic antigen to yield an MDM score. Clinical information, including treatment and radiographic measurements of the tumor burden, were longitudinally collected., Results: Of the 35 patients, 18 had recurrence and 17 had no evidence of disease during the study period. The MDM score was positive in 16 out of 18 patients who recurred and only 2 of the 17 patients without recurrence. The MDM score detected recurrence in 12 patients preceding clinical or radiographic detection of recurrent CRC by a median of 106 days (range 90-232 days)., Conclusions: Plasma MDMs can detect recurrent CRC prior to radiographic detection; this tumor-agnostic liquid biopsy approach may assist cancer surveillance and monitoring.
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- 2023
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11. Assessing the capacity of methylated DNA markers of cervical squamous cell carcinoma to discriminate oropharyngeal squamous cell carcinoma in human papillomavirus mediated disease.
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Bartemes KR, Gochanour BR, Routman DM, Ma DJ, Doering KA, Burger KN, Foote PH, Taylor WR, Mahoney DW, Berger CK, Cao X, Then SS, Haller TJ, Larish AM, Moore EJ, Garcia JJ, Graham RP, Bakkum-Gamez JN, Kisiel JB, and Van Abel KM
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- Female, Humans, Squamous Cell Carcinoma of Head and Neck genetics, Human Papillomavirus Viruses, Genetic Markers, DNA Methylation, Papillomaviridae genetics, Carcinoma, Squamous Cell pathology, Papillomavirus Infections complications, Papillomavirus Infections diagnosis, Papillomavirus Infections genetics, Oropharyngeal Neoplasms, Uterine Cervical Neoplasms diagnosis, Uterine Cervical Neoplasms genetics, Head and Neck Neoplasms genetics
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Objective: Early identification of human papillomavirus associated oropharyngeal squamous cell carcinoma (HPV(+)OPSCC) is challenging and novel biomarkers are needed. We hypothesized that a panel of methylated DNA markers (MDMs) found in HPV(+) cervical squamous cell carcinoma (CSCC) will have similar discrimination in HPV(+)OPSCC tissues., Materials and Methods: Formalin-fixed, paraffin-embedded tissues were obtained from patients with primary HPV(+)OPSCC or HPV(+)CSCC; control tissues included normal oropharynx palatine tonsil (NOP) and cervix (NCS). Using a methylation-specific polymerase chain reaction, 21 previously validated cervical MDMs were evaluated on tissue-extracted DNA. Discrimination between case and control cervical and oropharynx tissue was assessed using area under the curve (AUC)., Results: 34 HPV(+)OPSCC, 36 HPV(+)CSCC, 26 NOP, and 24 NCS patients met inclusion criteria. Within HPV(+)CSCC, 18/21 (86%) of MDMs achieved an AUC ≥ 0.9 and all MDMs exhibited better than chance classifications relative to control cervical tissue (all p < 0.001). In contrast, within HPV(+)OPSCC only 5/21 (24%) MDMs achieved an AUC ≥ 0.90 but 19/21 (90%) exhibited better than chance classifications relative to control tonsil tissue (all p < 0.001). Overall, 13/21 MDMs had statistically significant lower AUCs in the oropharyngeal cohort compared to the cervical cohort, and only 1 MDM exhibited a statistically significant increase in AUC., Conclusions: Previously validated MDMs exhibited robust performance in independent HPV(+)CSCC patients. However, most of these MDMs exhibited higher discrimination for HPV(+)CSCC than for HPV(+)OPSCC. This suggests that each SCC subtype requires a unique set of MDMs for optimal discrimination. Future studies are necessary to establish an MDM panel for HPV(+)OPSCC., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Messrs. Taylor and Mahoney, and Drs. Van Abel, Routman, Ma, and Kisiel have disclosed inventions of Mayo Clinic intellectual property that are licensed to Exact Sciences (Madison, WI) for which they could earn royalties, paid to Mayo Clinic., (Copyright © 2023 Elsevier Ltd. All rights reserved.)
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- 2023
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12. Methylated DNA Markers for Sporadic Colorectal and Endometrial Cancer Are Strongly Associated with Lynch Syndrome Cancers.
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Bramblet RM, Bakkum-Gamez JN, Slettedahl SW, Foote PH, Taylor WR, Berger CK, Gysbers BJ, Arndt J, Chen L, Doering KA, Burger KN, Mahoney DW, Sherman ME, Kisiel JB, and Samadder NJ
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- Female, Humans, Genetic Markers, Risk Factors, Endometrium, Microsatellite Instability, Colorectal Neoplasms, Hereditary Nonpolyposis complications, Colorectal Neoplasms, Hereditary Nonpolyposis diagnosis, Colorectal Neoplasms, Hereditary Nonpolyposis genetics, Endometrial Neoplasms diagnosis, Endometrial Neoplasms genetics
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Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgical prophylaxis.To validate a panel of methylated DNA markers (MDM) previously identified in sporadic colorectal cancer and endometrial cancer for discrimination of these cancers in LS.In a case-control design, previously identified MDMs for the detection of colorectal cancer and endometrial cancer were assayed by qMSP on tissue-extracted DNA. Results were normalized to ACTB values within each sample. Least absolute shrinkage and selection operator models to classify colorectal cancer and endometrial cancer were trained on sporadic cases and controls and then applied to classify colorectal cancer and endometrial cancer, in those with LS, and cross-validated.We identified colorectal cancer cases (23 with LS, 48 sporadic), colorectal controls (32 LS, 48 sporadic), endometrial cancer cases (30 LS, 48 sporadic), and endometrial controls (29 LS, 37 sporadic). A 3-MDM panel (LASS4, LRRC4, and PPP2R5C) classified LS-CRC from LS controls with an AUC of 0.92 (0.84-0.99); results were similar for sporadic colorectal cancer. A 6-MDM panel (SFMBT2, MPZ, CYTH2, DIDO1, chr10.4479, and EMX2OS) discriminated LS-EC from LS controls with an AUC of 0.92 (0.83-1.0); the AUC for sporadic endometrial cancer versus sporadic controls was nominally higher, 0.99 (0.96-1.0).MDMs previously identified in sporadic endometrial cancer and colorectal cancer discriminate between endometrial cancer and benign endometrium and colorectal cancer and benign colorectum in LS. This supports the inclusion of patients with LS within future prospective clinical trials evaluating endometrial cancer and colorectal cancer MDMs and may provide a new avenue for cancer screening or surveillance in this high-risk population., Prevention Relevance: Lynch syndrome (LS) markedly increases risks of colorectal and endometrial cancers. Early detection biomarkers for LS cancers could reduce the needs for invasive screening and surgery. Methylated DNA markers previously identified in sporadic endometrial cancer and colorectal cancer discriminate between benign and cancer tissue in LS., (©2023 American Association for Cancer Research.)
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- 2023
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13. Plasma Methylated DNA Markers for Melanoma Surveillance.
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Berger CK, Taylor WR, Mahoney DW, Burger KN, Doering KA, Gonser AM, Cao X, Heilberger J, Gysbers BJ, Foote PH, Kottschade LA, Markovic SN, Lehman JS, Katerov VE, Allawi HT, Kisiel JB, and Meves A
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- Humans, Genetic Markers, Prospective Studies, DNA, Melanoma diagnosis, Melanoma genetics, Nevus
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Purpose: Surveillance after primary melanoma treatment aims to detect early signs of low-volume systemic disease. The current standard of care, surveillance imaging, is costly and difficult to access. We therefore sought to develop methylated DNA markers (MDMs) as promising alternatives for disease surveillance., Methods: We used reduced representation bisulfite sequencing (RRBS) to identify MDMs in DNA samples obtained from metastatic melanoma, benign nevi, and normal skin tissues. The identified MDMs underwent validation in an independent cohort of tissue and buffy coat DNA samples. Subsequently, we tested the validated MDMs in the plasma DNA of patients with metastatic melanoma undergoing surveillance with total body imaging and compared them with cancer-free controls. To estimate the overall predictive accuracy of the MDMs, we used random forest modeling with bootstrap cross-validation., Results: Forty MDMs demonstrated discrimination between melanoma cases and controls consisting of benign nevi and normal skin. Nine MDMs passing biological validation in tissue were run on 77 plasma samples from individuals with a history of metastatic melanoma, 49 of whom had evidence of disease detected by imaging at the time of blood draw, and 100 cancer-free controls. The cross-validated sensitivity of the panel for imaging-positive disease was 80% with a specificity of 100% in cancer-free controls, resulting in an overall AUC of 0.88 (95% CI, 0.81 to 0.96). The survival estimates for patients with melanoma who tested positive for the panel at 6 months and 1 year were 67% and 56%, respectively, while those who tested negative had survival rates of 100% and 92%., Conclusion: MDMs identified by RRBS demonstrate a high degree of concordance with imaging results in the plasma of patients with metastatic melanoma. Further prospective studies in larger intended use cohorts are needed to confirm these findings.
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- 2023
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14. Neoplasia Diagnosis After Multi-target Stool DNA Is Enhanced Among Lowest Baseline Detectors.
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Ebner DW, Burger KN, Mahoney DW, Broderick BT, Eckmann JD, Devens ME, Lowrie KL, League JB, Bering J, Kahn A, Rodriguez EA, Prichard DO, Wallace MB, Kane SV, Leighton JA, Buttar NS, Rutten LJF, Gurudu SR, and Kisiel JB
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- Humans, Male, Female, DNA, Neoplasm, Retrospective Studies, Early Detection of Cancer methods, Colonoscopy, Colorectal Neoplasms pathology, Adenoma pathology
- Abstract
Background and Aims: Variation in colorectal neoplasia detection limits the effectiveness of screening colonoscopy. By evaluating neoplasia detection rates of individual colonoscopists, we aimed to quantify the effects of pre-procedural knowledge of a positive (+) multi-target stool DNA (mt-sDNA) on colonoscopy quality metrics., Methods: We retrospectively identified physicians who performed a high volume of + mt-sDNA colonoscopies; colorectal neoplasia at post-mt-sDNA colonoscopy was recorded. These colonoscopists were stratified into quartiles based on baseline adenoma detection rates. Baseline colonoscopy adenoma detection rates and sessile serrated lesion detection rates were compared to post-mt-sDNA colonoscopy neoplasia diagnosis rates among each quartile. Withdrawal times were measured from negative exams., Results: During the study period (2014-17) the highest quartile of physicians by volume of post-mt-sDNA colonoscopies were evaluated. Among thirty-five gastroenterologists, their median screening colonoscopy adenoma detection rate was 32% (IQR, 28-39%) and serrated lesion detection rate was 13% (8-15%). After + mt-sDNA, adenoma diagnosis increased to 47% (36-56%) and serrated lesion diagnosis increased to 31% (17-42%) (both p < 0.0001). Median withdrawal time increased from 10 (7-13) to 12 (10-17) minutes (p < 0.0001) and was proportionate across quartiles. After + mt-sDNA, lower baseline detectors had disproportionately higher rates of adenoma diagnosis in female versus male patients (p = 0.048) and higher serrated neoplasia diagnosis rates among all patients (p = 0.0092)., Conclusions: Knowledge of + mt-sDNA enriches neoplasia diagnosis compared to average risk screening exams. Adenomatous and serrated lesion diagnosis was magnified among those with lower adenoma detection rates. Awareness of the mt-sDNA result may increase physician attention during colonoscopy. Pre-procedure knowledge of a positive mt-sDNA test improves neoplasia diagnosis rates among colonoscopists with lower baseline adenoma detection rates, independent of withdrawal time., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2023
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15. Multitarget Stool DNA Testing Has High Positive Predictive Value for Colorectal Neoplasia on the Second Round of Testing.
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Voss JK, Ebner DW, Burger KN, Mahoney DW, Devens ME, Lowrie KL, and Kisiel JB
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- Humans, Predictive Value of Tests, Retrospective Studies, DNA, Colonoscopy, Feces, Early Detection of Cancer, Mass Screening, Colorectal Neoplasms diagnosis, Colorectal Neoplasms genetics
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Background & Aims: Multitarget stool DNA (mt-sDNA) testing is a stool-based screening test for colorectal cancer (CRC). In a single instance of testing, the pivotal Food and Drug Administration-approval study (NCT01397747) found that 16% of mt-sDNA tests were positive, and the positive predictive value (PPV) for CRC or advanced precursor lesions (APL) was 27.3%. We aimed to examine real-world longitudinal performance by determining the test-positive rate and PPV of mt-sDNA on the second round of testing., Methods: Colonoscopy and pathology reports were reviewed retrospectively for patients with a negative mt-sDNA on the first round of screening and a positive mt-sDNA on the second round. The test-positivity rate and PPV for CRC, APL, and any colorectal neoplasia were calculated for the second mt-sDNA and compared with baseline PPVs from a previously published cohort of patients from our institution who tested positive on the first round of screening., Results: A total of 2758 patients completed a second test at a median of 3.2 years after the first test. Of these, 422 (15%) had a positive second mt-sDNA. The PPV was 0.25% for CRC, 24% for APL, and 67% for any colorectal neoplasia. There was no significant difference in PPV on the second mt-sDNA test compared with the first round (24% vs 28% for APL; P = .12)., Conclusions: mt-sDNA test positive rate and PPV were similar between the first and second rounds of screening. These observations confirm the utility of a second round of mt-sDNA screening and may inform estimates of mt-sDNA effectiveness for CRC screening., (Copyright © 2023 AGA Institute. Published by Elsevier Inc. All rights reserved.)
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- 2023
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16. Detection of endometrial cancer using tampon-based collection and methylated DNA markers.
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Bakkum-Gamez JN, Sherman ME, Slettedahl SW, Mahoney DW, Lemens MA, Laughlin-Tommaso SK, Hopkins MR, VanOosten A, Shridhar V, Staub JK, Cao X, Foote PH, Clarke MA, Burger KN, Berger CK, O'Connell MC, Doering KA, Podratz KC, DeStephano CC, Schoolmeester JK, Kerr SE, Wentzensen N, Taylor WR, and Kisiel JB
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- Humans, Female, Genetic Markers, Edetic Acid metabolism, Endometrium metabolism, DNA, DNA Methylation, Endometrial Neoplasms diagnosis, Endometrial Neoplasms genetics, Endometrial Neoplasms metabolism
- Abstract
Objective: Alterations in DNA methylation are early events in endometrial cancer (EC) development and may have utility in EC detection via tampon-collected vaginal fluid., Methods: For discovery, DNA from frozen EC, benign endometrium (BE), and benign cervicovaginal (BCV) tissues underwent reduced representation bisulfite sequencing (RRBS) to identify differentially methylated regions (DMRs). Candidate DMRs were selected based on receiver operating characteristic (ROC) discrimination, methylation level fold-change between cancers and controls, and absence of background CpG methylation. Methylated DNA marker (MDM) validation was performed using qMSP on DNA from independent EC and BE FFPE tissue sets. Women ≥45 years of age with abnormal uterine bleeding (AUB) or postmenopausal bleeding (PMB) or any age with biopsy-proven EC self-collected vaginal fluid using a tampon prior to clinically indicated endometrial sampling or hysterectomy. Vaginal fluid DNA was assayed by qMSP for EC-associated MDMs. Random forest modeling analysis was performed to generate predictive probability of underlying disease; results were 500-fold in-silico cross-validated., Results: Thirty-three candidate MDMs met performance criteria in tissue. For the tampon pilot, 100 EC cases were frequency matched by menopausal status and tampon collection date to 92 BE controls. A 28-MDM panel highly discriminated between EC and BE (96% (95%CI 89-99%) specificity; 76% (66-84%) sensitivity (AUC 0.88). In PBS/EDTA tampon buffer, the panel yielded 96% (95% CI 87-99%) specificity and 82% (70-91%) sensitivity (AUC 0.91)., Conclusion: Next generation methylome sequencing, stringent filtering criteria, and independent validation yielded excellent candidate MDMs for EC. EC-associated MDMs performed with promisingly high sensitivity and specificity in tampon-collected vaginal fluid; PBS-based tampon buffer with added EDTA improved sensitivity. Larger tampon-based EC MDM testing studies are warranted., (Copyright © 2023 Elsevier Inc. All rights reserved.)
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- 2023
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17. Positive Predictive Value for Multitarget Stool DNA After Bariatric and Metabolic Surgery.
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Ebner DW, Burger KN, Broderick B, Mahoney DW, Kellogg TA, Acosta A, and Kisiel JB
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Background and Aims: Bariatric and metabolic surgery (BMS) may adversely affect noninvasive stool tests for colorectal cancer (CRC) screening through several mechanisms. Multitarget stool DNA (mt-sDNA) is approved for CRC screening; however, performance in post-BMS patients is unknown. As the rates of BMS are anticipated to increase with rising incidence of obesity, it is important to evaluate mt-sDNA test performance among these patients., Methods: In a multisite academic and community-based practice, we obtained mt-sDNA results from 10/2014 to 12/2019 through electronic records and an institutional BMS registry. Average CRC risk patients with BMS prior to a positive mt-sDNA underwent a detailed chart review. Follow-up colonoscopy findings were compared to those among BMS patients screened with colonoscopy alone and a historical cohort of patients without BMS, screened by mt-sDNA. The primary study endpoint was the positive predictive value (PPV) for advanced colorectal neoplasia., Results: Among 336 average-risk patients who had mt-sDNA after BMS, mt-sDNA was positive in 49 (14.6%), 47/49 (96%) underwent follow-up colonoscopy, and the PPV for advanced neoplasia was 12/47 (25.5%). This is similar to the PPV for advanced colorectal neoplasia (425/1542, 28%) in a historical cohort of persons without prior BMS, screened by mt-sDNA at our center ( P = .86). Among those who had prior BMS, the rate of advanced neoplasia was higher after mt-sDNA compared to screening colonoscopy alone., Conclusion: Despite anatomic and physiologic mechanisms that could alter blood or DNA content in stool, BMS does not appear to adversely affect the PPV of mt-sDNA., Competing Interests: Conflicts of Interest: Dr Kisiel and Mr Mahoney are listed as inventors of Mayo Clinic intellectual property that is licensed to Exact Sciences (Madison, WI) and receive royalties, paid to Mayo Clinic. The remaining authors disclose no conflicts.
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- 2023
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18. Tissue methylated DNA markers for sporadic pancreatic cancer are strongly associated with familial and genetically predisposed pancreatic cancer.
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Majumder S, Taylor WR, Foote PH, Gysbers BJ, Cao X, Mahoney DW, Burger KN, Doering KA, Graham RP, Couch FJ, Petersen GM, and Kisiel JB
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- Genetic Markers, Genetic Predisposition to Disease, Humans, Carcinoma, Pancreatic Ductal diagnosis, Carcinoma, Pancreatic Ductal genetics, Carcinoma, Pancreatic Ductal pathology, Pancreatic Neoplasms diagnosis, Pancreatic Neoplasms genetics, Pancreatic Neoplasms pathology
- Abstract
High-risk individuals (HRIs) with familial and genetic predisposition to pancreatic ductal adenocarcinoma (PDAC) are eligible for screening. There is no accurate biomarker for detecting early-stage PDAC. We previously demonstrated that a panel of methylated DNA markers (MDMs) accurately detect sporadic PDAC. In this study we compared the distribution of MDMs in DNA extracted from tissue of PDAC cases who carry germline mutations and non-carriers with family history, with control tissue and demonstrate high discrimination like that seen in sporadic PDAC. These results provide scientific rationale for examining plasma MDMs in HRIs with the goal of developing a minimally-invasive early detection test., (Copyright © 2022. Published by Elsevier B.V.)
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- 2022
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19. Methylated DNA markers for plasma detection of ovarian cancer: Discovery, validation, and clinical feasibility.
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Marinelli LM, Kisiel JB, Slettedahl SW, Mahoney DW, Lemens MA, Shridhar V, Taylor WR, Staub JK, Cao X, Foote PH, Burger KN, Berger CK, O'Connell MC, Doering KA, Giakoumopoulos M, Berg H, Volkmann C, Solsrud A, Allawi HT, Kaiser M, Vaccaro AM, Albright Crawford C, Moehlenkamp C, Shea G, Deist MS, Schoolmeester JK, Kerr SE, Sherman ME, and Bakkum-Gamez JN
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- Biomarkers, Tumor genetics, CELF Proteins genetics, Carcinoma, Ovarian Epithelial diagnosis, Carcinoma, Ovarian Epithelial genetics, Feasibility Studies, Female, Genetic Markers, Humans, Nerve Tissue Proteins genetics, Transaminases genetics, DNA Methylation, Ovarian Neoplasms diagnosis, Ovarian Neoplasms genetics
- Abstract
Objective: Aberrant DNA methylation is an early event in carcinogenesis which could be leveraged to detect ovarian cancer (OC) in plasma., Methods: DNA from frozen OC tissues, benign fallopian tube epithelium (FTE), and buffy coats from cancer-free women underwent reduced representation bisulfite sequencing (RRBS) to identify OC MDMs. Candidate MDM selection was based on receiver operating characteristic (ROC) discrimination, methylation fold change, and low background methylation among controls. Blinded biological validation was performed using methylated specific PCR on DNA extracted from independent OC and FTE FFPE tissues. MDMs were tested using Target Enrichment Long-probe Quantitative Amplified Signal (TELQAS) assays in pre-treatment plasma from women newly diagnosed with OC and population-sampled healthy women. A random forest modeling analysis was performed to generate predictive probability of disease; results were 500-fold in silico cross-validated., Results: Thirty-three MDMs showed marked methylation fold changes (10 to >1000) across all OC subtypes vs FTE. Eleven MDMs (GPRIN1, CDO1, SRC, SIM2, AGRN, FAIM2, CELF2, RIPPLY3, GYPC, CAPN2, BCAT1) were tested on plasma from 91 women with OC (73 (80%) high-grade serous (HGS)) and 91 without OC; the cross-validated 11-MDM panel highly discriminated OC from controls (96% (95% CI, 89-99%) specificity; 79% (69-87%) sensitivity, and AUC 0.91 (0.86-0.96)). Among the 5 stage I/II HGS OCs included, all were correctly identified., Conclusions: Whole methylome sequencing, stringent filtering criteria, and biological validation yielded candidate MDMs for OC that performed with high sensitivity and specificity in plasma. Larger plasma-based OC MDM studies, including testing of pre-diagnostic specimens, are warranted., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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20. Discovery and Validation of Methylated DNA Markers From Pancreatic Neuroendocrine Tumors.
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Majumder S, Halfdanarson TR, Berger CK, Foote PH, Cao X, McGlinch MC, Gysbers BJ, de La Fuente J, Robran MJ, Doering KA, Burger KN, Bamlet WE, Oberg AL, Mahoney DW, Graham RP, Taylor WR, Petersen GM, and Kisiel JB
- Abstract
Background and Aims: Methylated DNA markers (MDMs) accurately identify several different cancer types, but there are limited data for pancreatic neuroendocrine tumors (pNETs). We aimed to identify MDM candidates in tissue that differentiate pNETs from normal pancreas., Methods: wUsing DNA from frozen normal pancreas (13) and pNET (51) tissues, we performed reduced representation bisulfite sequencing for MDM discovery. Validation in independent formalin fixed paraffin embedded tissues used pNET cases (67; solid = 50, cystic = 17), normal pancreas (24), and buffy coat (36) controls. Primary pNET MDM distributions were compared with lung (36), small bowel (36) NETs, and metastatic pNET (25) tissues. The discrimination accuracy was summarized as the area under the receiver operator characteristic curve (AUC) with corresponding 95% confidence intervals (CIs). Fisher's linear discriminant analysis was performed to estimate a linear discriminate score (LDS) differentiating normal from pNET tissue and applied to all patient groups; discrimination accuracy of the LDS was summarized as the bootstrap cross-validated AUC., Results: Median AUC for distinguishing normal pancreas from pNET tissue was 0.91 (interquartile range: 0.80-0.93). The cross-validated AUC for the LDS discriminating normal pancreatic tissue from primary and metastatic pNETs was 0.957 (95% CI 0.858-1.0, P < .0001) and 0.963 (95% CI 0.865-1.0, P < .0001), respectively. The LDS for the MDM panel was significantly higher for primary pNET, metastatic pNET, lung NET, and small bowel NET, each compared with normal pancreas tissue ( P < .0001). There was no statistical difference between primary pNET and metastatic pNET ( P = .1947)., Conclusion: In independent tissue validation, MDMs accurately discriminate pNETs from normal pancreas. These results provide scientific rationale for exploration of these tissue MDMs in a plasma-based assay for clinical application., (© 2022 The Authors.)
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- 2022
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21. High Positive Predictive Value of Multitarget Stool DNA After Aerodigestive Tract Radiotherapy.
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Ebner DW, Eckmann JD, Burger KN, Mahoney DW, Whitaker TJ, Petersen IA, and Kisiel JB
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Background and Aims: Multitarget stool DNA (mt-sDNA) is approved for average-risk colorectal cancer screening; test performance in persons with prior radiation therapy (RT) has not been studied. RT can induce gastrointestinal bleeding and alter DNA methylation, which may affect mt-sDNA accuracy. Among patients previously treated with RT, we aimed to measure the positive predictive value (PPV) of mt-sDNA and compare these results to historical estimates of mt-sDNA PPV among average-risk patients., Methods: After institutional review board approval, we conducted a retrospective cohort study of a multisite academic and community-based practice. Patients with RT and subsequent mt-sDNA use during the study period (2014-2016) were identified. The findings at diagnostic colonoscopy were compared with published reports among average-risk patients. Nominal P values were generated by 2-tailed Fisher's exact testing in comparisons of colorectal neoplasia (CRN) rates between groups., Results: There were 220 patients who had RT before mt-sDNA testing. RT was delivered along the aerodigestive tract in 108 patients. Mt-sDNA tests were positive in 45 of 220 patients (20%), and colonoscopy findings were available for 42; 31 of 42 patients (74%) had CRN. PPV by mt-sDNA was similar when stratified by site of prior RT (along vs outside the aerodigestive tract; P = 1.00). Detection of advanced CRN (36%) was nominally higher than previously published retrospective (27%) and prospective (20%) studies. The median time from the start of RT to mt-sDNA use was 7 (interquartile range, 3-14) years., Conclusion: With a test positivity rate and PPV for CRN similar to reports among average-risk patients, prior RT does not appear to adversely affect mt-sDNA performance., Competing Interests: Conflicts of Interest: J.B.K. and D.W.M. are listed as inventors of Mayo Clinic intellectual property that is licensed to Exact Sciences (Madison WI) and could receive royalties, paid to Mayo Clinic. The remaining authors disclose no conflicts.
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- 2022
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22. Detection of Postcolonoscopy Colorectal Neoplasia by Multi-target Stool DNA.
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Ebner DW, Eckmann JD, Burger KN, Mahoney DW, Bering J, Kahn A, Rodriguez EA, Prichard DO, Wallace MB, Kane SV, Finney Rutten LJ, Gurudu SR, and Kisiel JB
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- Adenoma diagnosis, Aged, Early Detection of Cancer, Female, Humans, Male, Middle Aged, Precancerous Conditions diagnosis, Predictive Value of Tests, Retrospective Studies, Colonoscopy, Colorectal Neoplasms diagnosis, DNA, Neoplasm analysis, Feces chemistry, Mass Screening methods
- Abstract
Introduction: Significant variability between colonoscopy operators contributes to postcolonoscopy colorectal cancers (CRCs). We aimed to estimate postcolonoscopy colorectal neoplasia (CRN) detection by multi-target stool DNA (mt-sDNA), which has not previously been studied for this purpose., Methods: In a retrospective cohort of patients with +mt-sDNA and completed follow-up colonoscopy, positive predictive value (PPV) for endpoints of any CRN, advanced adenoma, right-sided neoplasia, sessile serrated polyps (SSP), and CRC were stratified by the time since previous colonoscopy (0-9, 10, and ≥11 years). mt-sDNA PPV at ≤9 years from previous average-risk screening colonoscopy was used to estimate CRN missed at previous screening colonoscopy., Results: Among the 850 studied patients with +mt-sDNA after a previous negative screening colonoscopy, any CRN was found in 535 (PPV 63%). Among 107 average-risk patients having +mt-sDNA ≤9 years after last negative colonoscopy, any CRN was found in 67 (PPV 63%), advanced neoplasia in 16 (PPV 15%), right-sided CRN in 48 (PPV 46%), and SSP in 20 (PPV 19%). These rates were similar to those in 47 additional average risk persons with previous incomplete colonoscopy and in an additional 68 persons at increased CRC risk. One CRC (stage I) was found in an average risk patient who was mt-sDNA positive 6 years after negative screening colonoscopy., Discussion: The high PPV of mt-sDNA 0-9 years after a negative screening colonoscopy suggests that lesions were likely missed on previous examination or may have arisen de novo. mt-sDNA as an interval test after negative screening colonoscopy warrants further study., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of The American College of Gastroenterology.)
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- 2021
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23. High Detection Rates of Pancreatic Cancer Across Stages by Plasma Assay of Novel Methylated DNA Markers and CA19-9.
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Majumder S, Taylor WR, Foote PH, Berger CK, Wu CW, Mahoney DW, Bamlet WR, Burger KN, Postier N, de la Fuente J, Doering KA, Lidgard GP, Allawi HT, Petersen GM, Chari ST, Ahlquist DA, and Kisiel JB
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- Case-Control Studies, Comorbidity, Computational Biology methods, Female, Humans, Male, Neoplasm Staging, Pancreatic Neoplasms blood, ROC Curve, Biomarkers, Tumor, CA-19-9 Antigen blood, DNA Methylation, Pancreatic Neoplasms diagnosis, Pancreatic Neoplasms etiology
- Abstract
Purpose: We have previously identified tissue methylated DNA markers (MDMs) associated with pancreatic ductal adenocarcinoma (PDAC). In this case-control study, we aimed to assess the diagnostic performance of plasma MDMs for PDAC., Experimental Design: Thirteen MDMs ( GRIN2D, CD1D, ZNF781, FER1L4, RYR2, CLEC11A, AK055957, LRRC4, GH05J042948, HOXA1, PRKCB, SHISA9 , and NTRK3 ) were identified on the basis of selection criteria applied to results of prior tissue experiments and assays were optimized in plasma. Next, 340 plasma samples (170 PDAC cases and 170 controls) were assayed using target enrichment long-probe quantitative amplified signal method. Initially, 120 advanced-stage PDAC cases and 120 healthy controls were used to train a prediction algorithm at 97.5% specificity using random forest modeling. Subsequently, the locked algorithm derived from the training set was applied to an independent blinded test set of 50 early-stage PDAC cases and 50 controls. Finally, data from all 340 patients were combined, and cross-validated., Results: The cross-validated area under the receiver operating characteristic curve (AUC) for the training set was 0.93 (0.89-0.96) for the MDM panel alone, 0.91 (95% confidence interval, 0.87-0.96) for carbohydrate antigen 19-9 (CA19-9) alone, and 0.99 (0.98-1) for the combined MDM-CA19-9 panel. In the test set of early-stage PDAC, the AUC for MDMs alone was 0.84 (0.76-0.92), CA19-9 alone was 0.87 (0.79-0.94), and combined MDM-CA19-9 panel was 0.90 (0.84-0.97) significantly better compared with either MDMs alone or CA19-9 alone ( P = 0.0382 and 0.0490, respectively). At a preset specificity of 97.5%, the sensitivity for the combined panel in the test set was 80% (28%-99%) for stage I disease and 82% (68%-92%) for stage II disease. Using the combined datasets, the cross-validated AUC was 0.9 (0.86-0.94) for the MDM panel alone and 0.89 for CA19-9 alone (0.84-0.93) versus 0.97 (0.94-0.99) for the combined MDM-CA19-9 panel ( P ≤ 0.0001). Overall, cross-validated sensitivity of MDM-CA19-9 panel was 92% (83%-98%), with an observed specificity of 92% at the preset specificity of 97.5%., Conclusions: Plasma MDMs in combination with CA19-9 detect PDAC with significantly higher accuracy compared with either biomarker individually., (©2021 American Association for Cancer Research.)
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- 2021
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24. Novel Methylated DNA Markers in the Surveillance of Colorectal Cancer Recurrence.
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Xie H, Mahoney DW, Foote PH, Burger KN, Doering KA, Taylor WR, Then SS, Cao X, McGlinch M, Berger CK, Wu TT, Hubbard JM, Allawi HT, Kaiser MW, Lidgard GP, Ahlquist DA, and Kisiel JB
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- Aged, Case-Control Studies, Colorectal Neoplasms genetics, Colorectal Neoplasms surgery, Colorectal Neoplasms therapy, Feasibility Studies, Female, Humans, Male, Middle Aged, Neoplasm Recurrence, Local genetics, Neoplasm Recurrence, Local prevention & control, ROC Curve, Reproducibility of Results, Biomarkers, Tumor genetics, Colorectal Neoplasms diagnosis, DNA Methylation, Neoplasm Recurrence, Local diagnosis, Watchful Waiting methods
- Abstract
Purpose: We aimed to assess the concordance of colorectal cancer-associated methylated DNA markers (MDM) in primary and metastatic colorectal cancer for feasibility in detection of distantly recurrent/metastatic colorectal cancer in plasma., Experimental Design: A panel of previously discovered colorectal cancer-associated MDMs was selected. MDMs from primary and paired metastatic colorectal cancer tissue were assayed with quantitative methylation-specific PCR. Plasma MDMs were measured blindly by target enrichment long-probe quantitative-amplified signal assays. Random forest modeling was used to derive a prediction algorithm of MDMs in archival plasma samples from primary colorectal cancer cases. This algorithm was validated in prospectively collected plasma samples from recurrent colorectal cancer cases. The accuracy of the algorithm was summarized as sensitivity, specificity, and area under the curve (AUC)., Results: Of the 14 selected MDMs, the concordance between primary and metastatic tissue was considered moderate or higher for 12 MDMs (86%). At a preset specificity of 95% (91%-98%), a panel of 13 MDMs, in plasma from 97 colorectal cancer cases and 200 controls, detected stage IV colorectal cancer with 100% (80%-100%) sensitivity and all stages of colorectal cancer with an AUC of 0.91 (0.87-0.95), significantly higher than carcinoembryonic antigen [AUC, 0.72 (0.65-0.79)]. This panel, in plasma from 40 cases and 60 healthy controls, detected recurrent/metastatic colorectal cancer with 90% (76%-97%) sensitivity, 90% (79%-96%) specificity, and an AUC of 0.96 (0.92-1.00). The panel was positive in 0.30 (0.19-0.43) of 60 patients with no evidence of disease in post-operative patients with colorectal cancer., Conclusions: Plasma assay of novel colorectal cancer-associated MDMs can reliably detect both primary colorectal cancer and distantly recurrent colorectal cancer with promising accuracy., (©2020 American Association for Cancer Research.)
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- 2021
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25. Comparison of Tissue-Based Molecular Markers in Younger versus Older Patients with Colorectal Neoplasia.
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Limburg PJ, Mahoney DW, Ahlquist DA, Allawi HT, Johnson SC, Kaiser M, Katerov VE, Statz S, Graham RP, Foote PH, Doering KA, Burger KN, Lidgard GP, and Kisiel JB
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- Age Factors, Early Detection of Cancer, Female, Humans, Male, Middle Aged, Colorectal Neoplasms epidemiology
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Background: Emerging colorectal cancer trends demonstrate increased incidence and mortality in younger populations, prompting consideration of average-risk colorectal cancer screening initiation at age 45 versus 50 years. However, screening test performance characteristics in adults 45-49 years have been minimally described. To inform the biologic rationale for multi-target stool DNA (mt-sDNA) screening in younger patients, we analyzed and compared tissue levels of methylation ( BMP3, NDRG4 ) and mutation ( KRAS ) markers included in the FDA-approved, mt-sDNA assay (Cologuard; Exact Sciences Corporation)., Methods: Within 40-44, 45-49, and 50-64 year age groups, archived colorectal tissue specimens were identified for 211 sporadic colorectal cancer cases, 123 advanced precancerous lesions (APLs; adenomas >1 cm, high-grade dysplasia, ≥25% villous morphology, or sessile serrated polyp; 45-49 and 50-64 age groups only), and 204 histologically normal controls. Following DNA extraction, KRAS, BMP3 , and NDRG4 were quantified using QuARTS assays, relative to ACTB (reference gene)., Results: None of the molecular marker concentrations were significantly associated with age ( P > 0.05 for all comparisons), with the exception of NDRG4 concentration in APL samples (higher in older vs. younger cases; P = 0.008). However, NDRG4 levels were also statistically higher in APL case versus normal control samples in both the 45-49 ( P < 0.0001) and 50-64 ( P < 0.0001) year age groups., Conclusions: Overall, these findings support the potential for earlier onset of average-risk colorectal cancer screening with the mt-sDNA assay., Impact: These novel data address an identified knowledge gap and strengthen the biologic basis for earlier-onset, average-risk screening with the mt-sDNA assay., (©2020 American Association for Cancer Research.)
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- 2020
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26. Multitarget Stool DNA Screening in Clinical Practice: High Positive Predictive Value for Colorectal Neoplasia Regardless of Exposure to Previous Colonoscopy.
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Eckmann JD, Ebner DW, Bering J, Kahn A, Rodriguez E, Devens ME, Lowrie KL, Doering K, Then S, Burger KN, Mahoney DW, Prichard DO, Wallace MB, Gurudu SR, Finney LJ, Limburg P, Berger B, Ahlquist DA, and Kisiel JB
- Subjects
- Aged, Early Detection of Cancer, Female, Humans, Male, Middle Aged, Precancerous Conditions diagnosis, Predictive Value of Tests, Retrospective Studies, Colonoscopy, Colorectal Neoplasms diagnosis, DNA, Neoplasm analysis, Feces chemistry, Mass Screening methods
- Abstract
Objectives: Multitarget stool DNA (MT-sDNA) testing has grown as a noninvasive screening modality for colorectal cancer (CRC), but real-world clinical data are limited in the post-FDA approval setting. The effect of previous colonoscopy on MT-sDNA performance is not known. We aimed to evaluate findings of colorectal neoplasia (CRN) at diagnostic colonoscopy in patients with positive MT-sDNA testing, stratified by patient exposure to previous colonoscopy., Methods: We identified consecutive patients completing MT-sDNA testing over a 39-month period and reviewed the records of those with positive tests for neoplastic findings at diagnostic colonoscopy. MT-sDNA test positivity rate, adherence to diagnostic colonoscopy, and the positive predictive value (PPV) of MT-sDNA for any CRN and neoplastic subtypes were calculated., Results: Of 16,469 MT-sDNA tests completed, testing returned positive in 2,326 (14.1%) patients. After exclusion of patients at increased risk for CRC, 1,801 patients remained, 1,558 (87%) of whom underwent diagnostic colonoscopy; 918 of 1,558 (59%) of these patients had undergone previous colonoscopy, whereas 640 (41%) had not. Any CRN was found in 1,046 of 1,558 patients (PPV = 67%). More neoplastic lesions were found in patients without previous colonoscopy (73%); however, the rates remained high among those who had undergone previous colonoscopy (63%, P < 0.0001). The large majority (79%) of patients had right-sided neoplasia., Discussion: MT-sDNA has a high PPV for any CRN regardless of exposure to previous colonoscopy. Right-sided CRN was found at colonoscopy in most patients with positive MT-sDNA testing, representing a potential advantage over other currently available screening modalities for CRC.
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- 2020
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27. Discovery, Validation, and Application of Novel Methylated DNA Markers for Detection of Esophageal Cancer in Plasma.
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Qin Y, Wu CW, Taylor WR, Sawas T, Burger KN, Mahoney DW, Sun Z, Yab TC, Lidgard GP, Allawi HT, Buttar NS, Smyrk TC, Iyer PG, Katzka DA, Ahlquist DA, and Kisiel JB
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- Aged, Biomarkers, Tumor genetics, Case-Control Studies, Esophageal Neoplasms genetics, Female, Humans, Male, Middle Aged, ROC Curve, Rho Guanine Nucleotide Exchange Factors blood, Rho Guanine Nucleotide Exchange Factors genetics, Sialyltransferases blood, Sialyltransferases genetics, T-Box Domain Proteins blood, T-Box Domain Proteins genetics, Tumor Suppressor Proteins blood, Tumor Suppressor Proteins genetics, Biomarkers, Tumor blood, DNA Methylation, Early Detection of Cancer methods, Epigenome, Esophageal Neoplasms blood, Esophageal Neoplasms diagnosis
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Purpose: The burden of esophageal cancer continues to rise, and noninvasive screening tools are needed. Methylated DNA markers (MDM) assayed from plasma show promise in detection of other cancers. For esophageal cancer detection, we aimed to discover and validate MDMs in tissue, and determine their feasibility when assayed from plasma., Experimental Design: Whole-methylome sequencing was performed on DNA extracted from 37 tissues (28 EC; 9 normal esophagus) and 8 buffy coat samples. Top MDMs were validated by methylation specific PCR on tissue from 76 EC (41 adeno, 35 squamous cell) and 17 normal esophagus. Quantitative allele-specific real-time target and signal amplification was used to assay MDMs in plasma from 183 patients (85 EC, 98 controls). Recursive partitioning (rPART) identified MDM combinations predictive of esophageal cancer. Validation was performed in silico by bootstrapping., Results: From discovery, 23 candidate MDMs were selected for independent tissue validation; median area under the receiver operating curve (AUC) for individual MDMs was 0.93. Among 12 MDMs advanced to plasma testing, rPART modeling selected a 5 MDM panel ( FER1L4, ZNF671, ST8SIA1, TBX15, ARHGEF4 ) which achieved an AUC of 0.93 (95% CI, 0.89-0.96) on best-fit and 0.81 (95% CI, 0.75-0.88) on cross-validation. At 91% specificity, the panel detected 74% of esophageal cancer overall, and 43%, 64%, 77%, and 92% of stages I, II, III, and IV, respectively. Discrimination was not affected by age, sex, smoking, or body mass index., Conclusions: Novel MDMs assayed from plasma detect esophageal cancer with moderate accuracy. Further optimization and clinical testing are warranted., (©2019 American Association for Cancer Research.)
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- 2019
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28. Hepatocellular Carcinoma Detection by Plasma Methylated DNA: Discovery, Phase I Pilot, and Phase II Clinical Validation.
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Kisiel JB, Dukek BA, V S R Kanipakam R, Ghoz HM, Yab TC, Berger CK, Taylor WR, Foote PH, Giama NH, Onyirioha K, Abdallah MA, Burger KN, Slettedahl SW, Mahoney DW, Smyrk TC, Lewis JT, Giakoumopoulos M, Allawi HT, Lidgard GP, Roberts LR, and Ahlquist DA
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- Carcinoma, Hepatocellular, DNA Methylation, DNA, Neoplasm metabolism, Early Detection of Cancer methods, Female, Humans, Male, Middle Aged, Pilot Projects, Single-Blind Method, DNA, Neoplasm blood, Liver Neoplasms blood
- Abstract
Early detection improves hepatocellular carcinoma (HCC) outcomes, but better noninvasive surveillance tools are needed. We aimed to identify and validate methylated DNA markers (MDMs) for HCC detection. Reduced representation bisulfite sequencing was performed on DNA extracted from 18 HCC and 35 control tissues. Candidate MDMs were confirmed by quantitative methylation-specific PCR in DNA from independent tissues (74 HCC, 29 controls). A phase I plasma pilot incorporated quantitative allele-specific real-time target and signal amplification assays on independent plasma-extracted DNA from 21 HCC cases and 30 controls with cirrhosis. A phase II plasma study was then performed in 95 HCC cases, 51 controls with cirrhosis, and 98 healthy controls using target enrichment long-probe quantitative amplified signal (TELQAS) assays. Recursive partitioning identified best MDM combinations. The entire MDM panel was statistically cross-validated by randomly splitting the data 2:1 for training and testing. Random forest (rForest) regression models performed on the training set predicted disease status in the testing set; median areas under the receiver operating characteristics curve (AUCs; and 95% confidence interval [CI]) were reported after 500 iterations. In phase II, a six-marker MDM panel (homeobox A1 [HOXA1], empty spiracles homeobox 1 [EMX1], AK055957, endothelin-converting enzyme 1 [ECE1], phosphofructokinase [PFKP], and C-type lectin domain containing 11A [CLEC11A]) normalized by beta-1,3-galactosyltransferase 6 (B3GALT6) level yielded a best-fit AUC of 0.96 (95% CI, 0.93-0.99) with HCC sensitivity of 95% (88%-98%) at specificity of 92% (86%-96%). The panel detected 3 of 4 (75%) stage 0, 39 of 42 (93%) stage A, 13 of 14 (93%) stage B, 28 of 28 (100%) stage C, and 7 of 7 (100%) stage D HCCs. The AUC value for alpha-fetoprotein (AFP) was 0.80 (0.74-0.87) compared to 0.94 (0.9-0.97) for the cross-validated MDM panel (P < 0.0001). Conclusion: MDMs identified in this study proved to accurately detect HCC by plasma testing. Further optimization and clinical testing of this promising approach are indicated., (© 2018 by the American Association for the Study of Liver Diseases.)
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- 2019
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29. Long-term Follow-up of Patients Having False-Positive Multitarget Stool DNA Tests after Negative Screening Colonoscopy: The LONG-HAUL Cohort Study.
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Cotter TG, Burger KN, Devens ME, Simonson JA, Lowrie KL, Heigh RI, Mahoney DW, Johnson DH, Ahlquist DA, and Kisiel JB
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- Aged, Biomarkers, Tumor genetics, Case-Control Studies, Colonoscopy statistics & numerical data, DNA, Neoplasm analysis, Feces chemistry, Female, Follow-Up Studies, Humans, Logistic Models, Male, Middle Aged, Retrospective Studies, Colorectal Neoplasms diagnosis, Early Detection of Cancer methods, False Positive Reactions, Mass Screening methods
- Abstract
Background: Studies of colorectal cancer screening by multitarget stool DNA (MT-sDNA) show false-positive (FP) rates of 7% to 13%. It is unclear whether FP patients are at increased long-term risk of adverse outcomes. Methods: We compared subsequent clinical events among patients with apparent FP MT-sDNA with those in patients reported as true negative (TN). This was a retrospective cohort study of participants in pre-FDA approval MT-sDNA studies having nonadvanced or negative baseline colonoscopy findings from a single referral center. Per-protocol and calibrated cutoffs defined FP and TN groups. From the time of stool collection, we measured differences between FP and TN groups in time to death, subsequent cancer diagnosis, and onset of alarm symptoms. Results: Of 1,050 eligible patients, only 6 were lost to follow-up. Median age was 65.6 years [interquartile range (IQR), 56.8-72.3]; 54% were female. Median follow-up time was 4 years (IQR, 3.5-5.3). Eight aerodigestive (lung and gastrointestinal tract) cancers occurred. FP status by calibrated, but not per-protocol, cutoffs was associated with subsequent aerodigestive cancer; however, cumulative incidence did not exceed SEER expectations from the general population. By any cutoff method, FP status was not associated with mortality or alarm symptoms. Conclusions: Although FP status was associated with long-term aerodigestive cancers, new cases were not temporally related and did not exceed incidence estimates from general population. Impact: These observations do not justify aggressive follow-up evaluation for patients with FP MT-sDNA at this time. Larger studies are needed to confirm these early findings. Cancer Epidemiol Biomarkers Prev; 26(4); 614-21. ©2016 AACR ., (©2016 American Association for Cancer Research.)
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- 2017
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30. Multitarget stool DNA test: clinical performance and impact on yield and quality of colonoscopy for colorectal cancer screening.
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Johnson DH, Kisiel JB, Burger KN, Mahoney DW, Devens ME, Ahlquist DA, and Sweetser S
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- Adenoma genetics, Aged, Carcinoma genetics, Colonic Polyps genetics, Colorectal Neoplasms genetics, DNA analysis, Early Detection of Cancer, Female, Humans, Male, Middle Aged, Adenoma diagnosis, Carcinoma diagnosis, Colonic Polyps diagnosis, Colonoscopy, Colorectal Neoplasms diagnosis, DNA, Neoplasm analysis, Feces chemistry
- Abstract
Background and Aims: Multitarget stool DNA (MT-sDNA) testing is now approved by the U.S. Food and Drug Administration for average-risk colorectal cancer screening. Trials leading to its approval used blinded colonoscopy as the reference standard. In the postapproval screen setting, the clinical performance and impact of MT-sDNA testing on unblinded colonoscopy has not been described. We measured the impact that knowledge of a positive MT-sDNA test result has on colonoscopy yield and quality., Methods: The unblinded group comprised all patients with positive MT-sDNA results on screening from September 1, 2014 to September 30, 2015 at a single tertiary center. Off-label test patients were excluded. The blinded group included all MT-sDNA-positive participants in a preapproval screening study from the same center. Detailed colonoscopy findings and withdrawal times were recorded., Results: There were 172 MT-sDNA-positive patients in the unblinded group and 72 in the blinded group. More total adenomatous/sessile serrated polyps (70% vs 53%, P = .013) and advanced neoplasms (28% vs 21%, P = .27) were detected in unblinded than in blinded groups. Median numbers of polyps detected were 2 (IQR, 1-4) and 1 (IQR, 0-2) in unblinded and blinded groups, respectively (P = .0007). Among polyps detected, flat or slightly raised lesions in the right side of the colon were proportionately more frequent with unblinded (40%) than with blinded examinations (9%) (P = .0017). Median withdrawal time was 19 minutes (IQR, 13-29) in the unblinded group compared with 13 minutes (IQR, 10-20) in the blinded group (P = .0001)., Conclusions: Knowledge of a positive MT-sDNA result appears to have a beneficial impact on the diagnostic yield and quality of subsequent colonoscopy., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2017
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31. Patient-reported outcomes questionnaire compliance in Cancer Cooperative Group Trials (Alliance N0992).
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Atherton PJ, Burger KN, Pederson LD, Kaggal S, and Sloan JA
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- Adult, Aged, Aged, 80 and over, Female, Humans, Logistic Models, Male, Middle Aged, Quality of Life, Retrospective Studies, Surveys and Questionnaires, Young Adult, Clinical Trials as Topic, Neoplasms therapy, Patient Compliance, Patient Reported Outcome Measures
- Abstract
Background/aims: The use of patient-reported outcomes in clinical trials is a focal point for research and policy. Non-compliance with planned questionnaires and missing data can threaten both internal validity and generalizability. This retrospective analysis was conducted to determine the extent of, and characteristics associated with, missing patient-reported outcomes., Methods: Study characteristics, patient characteristics and adverse events, and reasons for non-compliance were compiled from 14 closed Alliance for Clinical Trials in Oncology, Mayo Clinic Cancer Center, or Mayo Clinic Cancer Research Consortium clinical trials. Compliance rates were calculated for each patient using the number of booklets completed while the patient was on trial divided by the number of booklets the patient was expected to complete. Frequency counts and summary statistics were compiled. Logistic regression techniques were employed., Results: The 1640 included patients had a median age of 58 years and were mostly White (90.8%) and female (73.8%). Compliance rates per study ranged from 84.7% to 97.2%. The primary endpoint of overall compliance rate was 93.1%. A total of 1267 patients were compliant. Those non-compliant were slightly older (mean = 58.6 vs 57.5, p = 0.03) and had different types of cancers (p < 0.01). There were no differences in compliance according to tumor status (p = 0.66), clinical stage (p = 0.81), baseline quality of life (p = 0.42 for ≥8 vs <8 and p = 0.12 for ≥6 vs <6), or maximum adverse event grade incidence (p = 0.33 for grade 2+ incidence and p = 0.36 for grade 3+ incidence). Reasons for non-compliance included patient refusal (N = 136), booklet not administered to patient (N = 199), no clinic visit at the scheduled time for booklet completion (N = 40), and at-home-completed booklet not returned (N = 224). Logistic regression indicates gender (p < 0.01), race (p < 0.01), performance score (p = 0.02), dose delay status (p = 0.01), and incidence of grade 3 or higher adverse event (p = 0.03) were correlates of compliance., Conclusion: Patient-reported outcomes have successfully been implemented into Alliance and Mayo Clinic trials with high rates of patient compliance. Further improvement in compliance can be made with staff commitment and education. Patients are typically non-compliant only when the task at hand is burdensome, unclear, or logistically challenging. Existing tracking systems used for the other trial outcomes should be utilized to ensure successful capture of patient-reported outcomes., Competing Interests: Declaration of conflicting interests There are no conflicts of interest to disclose for any of the authors., (© The Author(s) 2016.)
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- 2016
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32. The effect of immediate breast reconstruction on the timing of adjuvant chemotherapy: a systematic review.
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Xavier Harmeling J, Kouwenberg CA, Bijlard E, Burger KN, Jager A, and Mureau MA
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- Breast Neoplasms pathology, Chemotherapy, Adjuvant, Female, Humans, Mastectomy, Time Factors, Treatment Outcome, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Breast Neoplasms drug therapy, Breast Neoplasms surgery, Mammaplasty methods
- Abstract
Adjuvant chemotherapy is often needed to achieve adequate breast cancer control. The increasing popularity of immediate breast reconstruction (IBR) raises concerns that this procedure may delay the time to adjuvant chemotherapy (TTC), which may negatively impact oncological outcome. The current systematic review aims to investigate this effect. During October 2014, a systematic search for clinical studies was performed in six databases with keywords related to breast reconstruction and chemotherapy. Eligible studies met the following inclusion criteria: (1) research population consisted of women receiving therapeutic mastectomy, (2) comparison of IBR with mastectomy only groups, (3) TTC was clearly presented and mentioned as outcome measure, and (4) original studies only (e.g., cohort study, randomized controlled trial, case-control). Fourteen studies were included, representing 5270 patients who had received adjuvant chemotherapy, of whom 1942 had undergone IBR and 3328 mastectomy only. One study found a significantly shorter mean TTC of 12.6 days after IBR, four studies found a significant delay after IBR averaging 6.6-16.8 days, seven studies found no significant difference in TTC between IBR and mastectomy only, and two studies did not perform statistical analyses for comparison. In studies that measured TTC from surgery, mean TTC varied from 29 to 61 days for IBR and from 21 to 60 days for mastectomy only. This systematic review of the current literature showed that IBR does not necessarily delay the start of adjuvant chemotherapy to a clinically relevant extent, suggesting that in general IBR is a valid option for non-metastatic breast cancer patients.
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- 2015
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33. Trans-membrane area asymmetry controls the shape of cellular organelles.
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Beznoussenko GV, Pilyugin SS, Geerts WJ, Kozlov MM, Burger KN, Luini A, Derganc J, and Mironov AA
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- Animals, HeLa Cells, Humans, Intracellular Membranes metabolism, Protein Transport, Rats, Rats, Wistar, Intracellular Membranes chemistry, Membrane Fusion, Models, Biological
- Abstract
Membrane organelles often have complicated shapes and differ in their volume, surface area and membrane curvature. The ratio between the surface area of the cytosolic and luminal leaflets (trans-membrane area asymmetry (TAA)) determines the membrane curvature within different sites of the organelle. Thus, the shape of the organelle could be critically dependent on TAA. Here, using mathematical modeling and stereological measurements of TAA during fast transformation of organelle shapes, we present evidence that suggests that when organelle volume and surface area are constant, TAA can regulate transformation of the shape of the Golgi apparatus, endosomal multivesicular bodies, and microvilli of brush borders of kidney epithelial cells. Extraction of membrane curvature by small spheres, such as COPI-dependent vesicles within the Golgi (extraction of positive curvature), or by intraluminal vesicles within endosomes (extraction of negative curvature) controls the shape of these organelles. For instance, Golgi tubulation is critically dependent on the fusion of COPI vesicles with Golgi cisternae, and vice versa, for the extraction of membrane curvature into 50-60 nm vesicles, to induce transformation of Golgi tubules into cisternae. Also, formation of intraluminal ultra-small vesicles after fusion of endosomes allows equilibration of their TAA, volume and surface area. Finally, when microvilli of the brush border are broken into vesicles and microvilli fragments, TAA of these membranes remains the same as TAA of the microvilli. Thus, TAA has a significant role in transformation of organelle shape when other factors remain constant.
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- 2015
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34. Insertion of apoLp-III into a lipid monolayer is more favorable for saturated, more ordered, acyl-chains.
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Rathnayake SS, Mirheydari M, Schulte A, Gillahan JE, Gentit T, Phillips AN, Okonkwo RK, Burger KN, Mann EK, Vaknin D, Bu W, Agra-Kooijman DM, and Kooijman EE
- Subjects
- Animals, Hydrophobic and Hydrophilic Interactions, Locusta migratoria chemistry, Protein Structure, Secondary, Protein Unfolding, Scattering, Small Angle, X-Ray Diffraction, Apolipoproteins chemistry, Diglycerides chemistry, Insect Proteins chemistry, Phospholipids chemistry, Unilamellar Liposomes chemistry
- Abstract
Neutral lipid transport in mammals is complicated involving many types of apolipoprotein. The exchangeable apolipoproteins mediate the transfer of hydrophobic lipids between tissues and particles, and bind to cell surface receptors. Amphipathic α-helices form a common structural motif that facilitates their lipid binding and exchangeability. ApoLp-III, the only exchangeable apolipoprotein found in insects, is a model amphipathic α-helix bundle protein and its three dimensional structure and function mimics that of the mammalian proteins apoE and apoAI. Even the intracellular exchangeable lipid droplet protein TIP47/perilipin 3 contains an α-helix bundle domain with high structural similarity to that of apoE and apoLp-III. Here, we investigated the interaction of apoLp-III from Locusta migratoria with lipid monolayers. Consistent with earlier work we find that insertion of apoLp-III into fluid lipid monolayers is highest for diacylglycerol. We observe a preference for saturated and more highly ordered lipids, suggesting a new mode of interaction for amphipathic α-helix bundles. X-ray reflectivity shows that apoLp-III unfolds at a hydrophobic interface and flexible loops connecting the amphipathic α-helices stay in solution. X-ray diffraction indicates that apoLp-III insertion into diacylglycerol monolayers induces additional ordering of saturated acyl-chains. These results thus shed important new insight into the protein-lipid interactions of a model exchangeable apolipoprotein with significant implications for its mammalian counterparts., (© 2013 Elsevier B.V. All rights reserved.)
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- 2014
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35. Using the Skindex-16 and Common Terminology Criteria for Adverse Events to assess rash symptoms: results of a pooled-analysis (N0993).
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Atherton PJ, Burger KN, Loprinzi CL, Neben Wittich MA, Miller RC, Jatoi A, and Sloan JA
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- Algorithms, Anti-Inflammatory Agents therapeutic use, Antibodies, Monoclonal adverse effects, Antibodies, Monoclonal, Humanized, Breast Neoplasms radiotherapy, Cetuximab, Erlotinib Hydrochloride, Female, Gefitinib, Humans, Male, Middle Aged, Mometasone Furoate, Pregnadienediols therapeutic use, Protein Kinase Inhibitors adverse effects, Protein Synthesis Inhibitors therapeutic use, Quinazolines adverse effects, Radiodermatitis prevention & control, Randomized Controlled Trials as Topic, Sunscreening Agents therapeutic use, Surveys and Questionnaires, Tetracycline therapeutic use, Antineoplastic Agents adverse effects, Exanthema chemically induced, Exanthema classification, Neoplasms complications, Neoplasms therapy, Radiodermatitis classification, Severity of Illness Index, Terminology as Topic
- Abstract
Background: Historically, skin toxicity has been assessed in prospective clinical trials using the clinician-reported National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE). The patient-reported Skindex-16 measures symptoms and perceptions of toxicity. This study was designed to compare information provided by these two measures., Methods: Data were compiled from three placebo-controlled North Central Cancer Treatment Group studies (N06C4, N03CB, N05C4) having rash prevention as the primary objective. All used the Skindex-16 and CTCAE at baseline, weekly during treatment and during a minimum 2-week follow-up period. Statistical procedures, including Pearson correlations, were utilized to determine relationships between adverse event (AE) grades and Skindex-16 scores., Results: Four hundred and twelve individual patients provided data (median age, 61; 134 male). Patients' Skindex-16 score results show a 0.9 overall mean (range 0-6 with 6 being worse symptoms), a 0.4 baseline mean (range, 0-4.3) and a 1.3 end-of-treatment mean (range, 0-5.9). Ninety-three, 142 and 177 patients experienced a grade 0, 1 and 2+ CTCAE skin toxicity, respectively. Baseline Skindex-16 scores had relatively low correlation with CTCAE grades. The correlation of rash grade with Skindex-16 scores ranged from r = 0.49 with the function subscale to r = 0.62 with the symptom subscale. The highest correlations of the maximum grade of any dermatological AE with the Skindex-16 were r = 0.48 for the total score and r = 0.55 for the symptom subscale., Conclusions: The data reported support the decision to include both measures in a clinical trial to assess the patient experience, as each measure may specifically target varying symptoms and intensities.
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- 2012
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36. Spiritual well-being and quality of life of women with ovarian cancer and their spouses.
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Frost MH, Johnson ME, Atherton PJ, Petersen WO, Dose AM, Kasner MJ, Burger KN, Sloan JA, and Pipe TB
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- Adaptation, Psychological, Adult, Aged, Aged, 80 and over, Female, Humans, Longitudinal Studies, Male, Mental Health, Middle Aged, Socioeconomic Factors, Surveys and Questionnaires, Ovarian Neoplasms psychology, Quality of Life, Spirituality, Spouses psychology
- Abstract
Background: There is little research on the quality of life (QOL) and spiritual well-being (SWB) of women diagnosed with ovarian cancer and their spouses., Objective: We compared the SWB and QOL of these women and their spouses over a 3-year period., Methods: This is a descriptive, longitudinal study involving 70 women with ovarian cancer and 26 spouses. Questionnaires were completed postoperatively and by mail 3, 7, 12, 18, 24, and 36 months later. All participants completed the Functional Assessment of Chronic Illness Therapy (FACIT)-Spiritual Well-Being-Expanded Version, Symptom Distress Scale, and open-ended questions about changes in their lives. Diagnosed women completed the FACIT-Ovarian and spouses the Caregiver Burden Interview and Linear Analog Self-Assessment scales., Results: Women reported a high level of SWB over time. Spouses' SWB was significantly worse than the women's at 1 and 3 years (P ≤ .05). Insomnia, fatigue, and outlook/worry were problematic across time, with no significant differences between women and spouses except that women experienced more insomnia through 3 months (P = .02). Emotional well-being was compromised over time for the women but not their spouses until year 3. Physical and social well-being were compromised in spouses across time, while women's social well-being remained high and physical well-being was problematic only for the first year., Limitations: Limitations include a small spouse sample and, due to the disease process, attrition over time., Conclusions: Ovarian cancer has significant, but different, effects on women and spouses. Some effects are static, while others are not, which underscores the need for continual monitoring., (Copyright © 2012 Elsevier Inc. All rights reserved.)
- Published
- 2012
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37. Dietary fiber, carbohydrate quality and quantity, and mortality risk of individuals with diabetes mellitus.
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Burger KN, Beulens JW, van der Schouw YT, Sluijs I, Spijkerman AM, Sluik D, Boeing H, Kaaks R, Teucher B, Dethlefsen C, Overvad K, Tjønneland A, Kyrø C, Barricarte A, Bendinelli B, Krogh V, Tumino R, Sacerdote C, Mattiello A, Nilsson PM, Orho-Melander M, Rolandsson O, Huerta JM, Crowe F, Allen N, and Nöthlings U
- Subjects
- Adult, Aged, Body Mass Index, Cardiovascular Diseases complications, Cardiovascular Diseases mortality, Cardiovascular Diseases physiopathology, Cohort Studies, Diabetes Mellitus, Type 2 complications, Diabetes Mellitus, Type 2 physiopathology, Female, Glycemic Index drug effects, Humans, Male, Middle Aged, Risk, Smoking, Diabetes Mellitus, Type 2 mortality, Dietary Carbohydrates analysis, Dietary Carbohydrates pharmacology, Dietary Fiber analysis, Dietary Fiber pharmacology
- Abstract
Background: Dietary fiber, carbohydrate quality and quantity are associated with mortality risk in the general population. Whether this is also the case among diabetes patients is unknown., Objective: To assess the associations of dietary fiber, glycemic load, glycemic index, carbohydrate, sugar, and starch intake with mortality risk in individuals with diabetes., Methods: This study was a prospective cohort study among 6,192 individuals with confirmed diabetes mellitus (mean age of 57.4 years, and median diabetes duration of 4.4 years at baseline) from the European Prospective Investigation into Cancer and Nutrition (EPIC). Dietary intake was assessed at baseline (1992-2000) with validated dietary questionnaires. Cox proportional hazards analysis was performed to estimate hazard ratios (HRs) for all-cause and cardiovascular mortality, while adjusting for CVD-related, diabetes-related, and nutritional factors., Results: During a median follow-up of 9.2 y, 791 deaths were recorded, 306 due to CVD. Dietary fiber was inversely associated with all-cause mortality risk (adjusted HR per SD increase, 0.83 [95% CI, 0.75-0.91]) and CVD mortality risk (0.76[0.64-0.89]). No significant associations were observed for glycemic load, glycemic index, carbohydrate, sugar, or starch. Glycemic load (1.42[1.07-1.88]), carbohydrate (1.67[1.18-2.37]) and sugar intake (1.53[1.12-2.09]) were associated with an increased total mortality risk among normal weight individuals (BMI≤25 kg/m(2); 22% of study population) but not among overweight individuals (P interaction≤0.04). These associations became stronger after exclusion of energy misreporters., Conclusions: High fiber intake was associated with a decreased mortality risk. High glycemic load, carbohydrate and sugar intake were associated with an increased mortality risk in normal weight individuals with diabetes.
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- 2012
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38. Comparison of provider-assessed and patient-reported outcome measures of acute skin toxicity during a Phase III trial of mometasone cream versus placebo during breast radiotherapy: the North Central Cancer Treatment Group (N06C4).
- Author
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Neben-Wittich MA, Atherton PJ, Schwartz DJ, Sloan JA, Griffin PC, Deming RL, Anders JC, Loprinzi CL, Burger KN, Martenson JA, and Miller RC
- Subjects
- Communication, Erythema etiology, Erythema prevention & control, Female, Humans, Mometasone Furoate, Prospective Studies, Pruritus etiology, Pruritus prevention & control, Quality of Life, Radiodermatitis complications, Treatment Outcome, Breast Neoplasms radiotherapy, Dermatologic Agents therapeutic use, Outcome Assessment, Health Care methods, Pregnadienediols therapeutic use, Radiodermatitis prevention & control
- Abstract
Purpose: Considerable interobserver variability exists among providers and between providers and patients when measuring subjective symptoms. In the recently published Phase III N06C4 trial of mometasone cream vs. placebo to prevent radiation dermatitis, the primary provider-assessed (PA) endpoint, using the Common Toxicity Criteria for Adverse Events (CTCAE), was negative. However, prospectively planned secondary analyses of patient-reported outcomes (PROs), using the Skindex-16 and Skin Toxicity Assessment Tool (STAT), were positive. This study assesses the relationship between PA outcomes and PROs., Methods and Materials: Pearson correlation coefficients were calculated to compare the three tools. Statistical correlations were defined as follows: <0.5, mild; 0.5-0.7, moderate; and >0.7, strong., Results: CTCAE dermatitis moderately correlated with STAT erythema, and CTCAE pruritus strongly correlated with STAT itching. CTCAE pruritus had a moderate correlation with Skindex-16 itching. Comparing the 2 PRO tools, Skindex-16 itching correlated moderately with STAT itching. Skindex-16 burning, hurting, irritation, and persistence all showed the strongest correlation with STAT burning; they showed moderate correlations with STAT itching and tenderness., Conclusions: The PRO Skindex-16 correlated well with the PRO portions of STAT, but neither tool correlated well with CTCAE. PROs delineated a wider spectrum of toxicity than PA measures and provided more information on rash, redness, pruritus, and annoyance measures compared with CTCAE findings of rash and pruritus. PROs may provide a more complete measure of patient experience than single-symptom, PA endpoints in clinical trials assessing radiation skin toxicity., (Copyright © 2011 Elsevier Inc. All rights reserved.)
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- 2011
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39. Dietary glycemic load and glycemic index and risk of coronary heart disease and stroke in Dutch men and women: the EPIC-MORGEN study.
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Burger KN, Beulens JW, Boer JM, Spijkerman AM, and van der A DL
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- Adult, Aged, Coronary Disease etiology, Dietary Carbohydrates adverse effects, Female, Humans, Male, Middle Aged, Netherlands epidemiology, Prospective Studies, Risk, Sex Distribution, Stroke etiology, Young Adult, Coronary Disease epidemiology, Dietary Carbohydrates analysis, Glycemic Index, Stroke epidemiology
- Abstract
Background: The associations of glycemic load (GL) and glycemic index (GI) with the risk of cardiovascular diseases (CVD) are not well-established, particularly in men, and may be modified by gender., Objective: To assess whether high dietary GL and GI increase the risk of CVD in men and women., Methods: A large prospective cohort study (EPIC-MORGEN) was conducted within the general Dutch population among 8,855 men and 10,753 women, aged 21-64 years at baseline (1993-1997) and free of diabetes and CVD. Dietary intake was assessed with a validated food-frequency questionnaire and GI and GL were calculated using Foster-Powell's international table of GI. Information on morbidity and mortality was obtained through linkage with national registries. Cox proportional hazards analysis was performed to estimate hazard ratios (HRs) for incident coronary heart disease (CHD) and stroke, while adjusting for age, CVD risk factors, and dietary factors., Results: During a mean follow-up of 11.9 years, 581 CHD cases and 120 stroke cases occurred among men, and 300 CHD cases and 109 stroke cases occurred among women. In men, GL was associated with an increased CHD risk (adjusted HR per SD increase, 1.17 [95% CI, 1.02-1.35]), while no significant association was found in women (1.09 [0.89-1.33]). GI was not associated with CHD risk in both genders, while it was associated with increased stroke risk in men (1.27 [1.02-1.58]) but not in women (0.96 [0.75-1.22]). Similarly, total carbohydrate intake and starch intake were associated with a higher CHD risk in men (1.23 [1.04-1.46]; and 1.24 [1.07-1.45]), but not in women., Conclusion: Among men, high GL and GI, and high carbohydrate and starch intake, were associated with increased risk of CVD.
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- 2011
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40. Phase III, randomized, double-blind, placebo-controlled evaluation of pregabalin for alleviating hot flashes, N07C1.
- Author
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Loprinzi CL, Qin R, Balcueva EP, Flynn KA, Rowland KM Jr, Graham DL, Erwin NK, Dakhil SR, Jurgens DJ, and Burger KN
- Subjects
- Adolescent, Adult, Double-Blind Method, Female, Follow-Up Studies, Hot Flashes pathology, Humans, Maximum Tolerated Dose, Middle Aged, Placebos, Postmenopause, Pregabalin, Prognosis, Quality of Life, Survival Rate, Treatment Outcome, Young Adult, gamma-Aminobutyric Acid therapeutic use, Anticonvulsants therapeutic use, Hot Flashes drug therapy, gamma-Aminobutyric Acid analogs & derivatives
- Abstract
Purpose: Hot flashes are a common problem for which effective and safe treatments are needed. The current trial was conducted on the basis of preliminary promising data that pregabalin decreased hot flashes., Patients and Methods: A double-blind, placebo-controlled, randomized trial design was used to compare pregabalin at target doses of 75 mg twice daily and 150 mg twice daily with a placebo. Hot flash frequencies and scores (frequency times mean severity) were recorded daily during a baseline week and for six treatment weeks. The primary end point for this study was the change-from-baseline hot flash score during treatment week 6 between the 150 mg twice daily target pregabalin treatment and placebo. Nonparametric Wilcoxon rank sum tests, two-sample t tests, and chi(2) tests were used to compare the primary and secondary hot flash efficacy end points between pregabalin treatments and placebo., Results: Hot flash score changes available for 163 patients during the sixth treatment week compared with a baseline week decreased by 50%, 65%, and 71% in the placebo, and target 75 mg twice daily and 150 mg twice daily pregabalin arms, respectively (P = .009 and P = .007, comparing respective pregabalin arms to the placebo arm). While some toxicities were significantly more common in the pregabalin arms, being more evident with the higher dose, pregabalin was generally well tolerated by most patients., Conclusion: Pregabalin decreases hot flashes and is reasonably well tolerated. A target dose of 75 mg twice daily is recommended. Its effects appear to be roughly comparable to what has been reported with gabapentin and with some newer antidepressants.
- Published
- 2010
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41. Biophysics and function of phosphatidic acid: a molecular perspective.
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Kooijman EE and Burger KN
- Subjects
- Hydrogen Bonding, Lipid Bilayers metabolism, Models, Biological, Static Electricity, Biophysical Phenomena, Phosphatidic Acids chemistry, Phosphatidic Acids metabolism
- Abstract
Phosphatidic acid is the simplest (diacyl)glycerophospholipid present in cells and is now a well established second messenger with direct biological functions. It is specifically recognized by diverse proteins and plays an important role in cellular signaling and membrane dynamics in all eukaryotes. An important determinant of the biological functions of phosphatidic acid is its anionic headgroup. In this review we will focus on the peculiar ionization properties of phosphatidic acid and their crucial role in lipid-protein interactions. We will take a molecular approach focusing entirely on the physical chemistry of the lipid and develop a model explaining the ionization properties of phosphatidic acid, termed the electrostatic-hydrogen bond switch model. Diverse examples from recent literature in support of this model will be presented and the broader implications of our findings will be discussed.
- Published
- 2009
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42. TIP47 functions in the biogenesis of lipid droplets.
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Bulankina AV, Deggerich A, Wenzel D, Mutenda K, Wittmann JG, Rudolph MG, Burger KN, and Höning S
- Subjects
- Amino Acid Sequence, Apolipoproteins, Cell Line, DNA-Binding Proteins metabolism, Humans, Intracellular Signaling Peptides and Proteins metabolism, Liposomes metabolism, Perilipin-3, Pregnancy Proteins metabolism, Protein Transport, Receptor, IGF Type 2, Triglycerides, Vesicular Transport Proteins, DNA-Binding Proteins physiology, Intracellular Signaling Peptides and Proteins physiology, Lipid Metabolism, Lipids, Pregnancy Proteins physiology
- Abstract
TIP47 (tail-interacting protein of 47 kD) was characterized as a cargo selection device for mannose 6-phosphate receptors (MPRs), directing their transport from endosomes to the trans-Golgi network. In contrast, our current analysis shows that cytosolic TIP47 is not recruited to organelles of the biosynthetic and endocytic pathways. Knockdown of TIP47 expression had no effect on MPR distribution or trafficking and did not affect lysosomal enzyme sorting. Therefore, our data argue against a function of TIP47 as a sorting device. Instead, TIP47 is recruited to lipid droplets (LDs) by an amino-terminal sequence comprising 11-mer repeats. We show that TIP47 has apolipoprotein-like properties and reorganizes liposomes into small lipid discs. Suppression of TIP47 blocked LD maturation and decreased the incorporation of triacylglycerol into LDs. We conclude that TIP47 functions in the biogenesis of LDs.
- Published
- 2009
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43. Quantitative label-free imaging of lipid composition and packing of individual cellular lipid droplets using multiplex CARS microscopy.
- Author
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Rinia HA, Burger KN, Bonn M, and Müller M
- Subjects
- Image Enhancement methods, Lipid Metabolism physiology, Lipids chemistry, Microscopy methods, Spectrum Analysis, Raman methods
- Abstract
Lipid droplets (LDs) are highly dynamic organelles that perform multiple functions, including the regulated storage and release of cholesterol and fatty acids. Information on the molecular composition of individual LDs within their cellular context is crucial in understanding the diverse biological functions of LDs, as well as their involvement in the development of metabolic disorders such as obesity, type II diabetes, and atherosclerosis. Although ensembles of LDs isolated from cells and tissues were analyzed in great detail, quantitative information on the heterogeneity in lipid composition of individual droplets, and possible variations within single lipid droplets, is lacking. Therefore, we used a label-free quantitative method to image lipids within LDs in 3T3-L1 cells. The method combines submicron spatial resolution in three dimensions, using label-free coherent anti-Stokes Raman scattering microscopy, with quantitative analysis based on the maximum entropy method. Our method allows quantitative imaging of the chemistry (level of acyl unsaturation) and physical state (acyl chain order) of individual LDs. Our results reveal variations in lipid composition and physical state between LDs contained in the same cell, and even within a single LD.
- Published
- 2008
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44. Diacylglycerol is required for the formation of COPI vesicles in the Golgi-to-ER transport pathway.
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Fernández-Ulibarri I, Vilella M, Lázaro-Diéguez F, Sarri E, Martínez SE, Jiménez N, Claro E, Mérida I, Burger KN, and Egea G
- Subjects
- Animals, Biological Transport drug effects, Brefeldin A pharmacology, COS Cells, Carrier Proteins metabolism, Cell Membrane drug effects, Cell Membrane metabolism, Chlorocebus aethiops, Diglycerides pharmacology, Endoplasmic Reticulum drug effects, Endoplasmic Reticulum ultrastructure, Estrenes pharmacology, GTPase-Activating Proteins metabolism, Golgi Apparatus drug effects, Golgi Apparatus ultrastructure, HeLa Cells, Humans, Phorbol 12,13-Dibutyrate pharmacology, Propranolol pharmacology, Pyrrolidinones pharmacology, Rats, Receptors, Peptide metabolism, Signal Transduction drug effects, COP-Coated Vesicles metabolism, Coat Protein Complex I metabolism, Diglycerides metabolism, Endoplasmic Reticulum metabolism, Golgi Apparatus metabolism
- Abstract
Diacylglycerol is necessary for trans-Golgi network (TGN) to cell surface transport, but its functional relevance in the early secretory pathway is unclear. Although depletion of diacylglycerol did not affect ER-to-Golgi transport, it led to a redistribution of the KDEL receptor to the Golgi, indicating that Golgi-to-ER transport was perturbed. Electron microscopy revealed an accumulation of COPI-coated membrane profiles close to the Golgi cisternae. Electron tomography showed that the majority of these membrane profiles originate from coated buds, indicating a block in membrane fission. Under these conditions the Golgi-associated pool of ARFGAP1 was reduced, but there was no effect on the binding of coatomer or the membrane fission protein CtBP3/BARS to the Golgi. The addition of 1,2-dioctanoyl-sn-glycerol or the diacylglycerol analogue phorbol 12,13-dibutyrate reversed the effects of endogenous diacylglycerol depletion. Our findings implicate diacylglycerol in the retrograde transport of proteins from Golgi to the ER and suggest that it plays a critical role at a late stage of COPI vesicle formation.
- Published
- 2007
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45. An electrostatic/hydrogen bond switch as the basis for the specific interaction of phosphatidic acid with proteins.
- Author
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Kooijman EE, Tieleman DP, Testerink C, Munnik T, Rijkers DT, Burger KN, and de Kruijff B
- Subjects
- Amino Acids, Basic chemistry, Computer Simulation, Hydrogen Bonding, Ions chemistry, Liposomes, Magnetic Resonance Spectroscopy, Models, Molecular, Peptides chemistry, Protein Structure, Tertiary, Static Electricity, Phosphatidic Acids chemistry, Proteins chemistry
- Abstract
Phosphatidic acid (PA) is a minor but important phospholipid that, through specific interactions with proteins, plays a central role in several key cellular processes. The simple yet unique structure of PA, carrying just a phosphomonoester head group, suggests an important role for interactions with the positively charged essential residues in these proteins. We analyzed by solid-state magic angle spinning 31P NMR and molecular dynamics simulations the interaction of low concentrations of PA in model membranes with positively charged side chains of membrane-interacting peptides. Surprisingly, lysine and arginine residues increase the charge of PA, predominantly by forming hydrogen bonds with the phosphate of PA, thereby stabilizing the protein-lipid interaction. Our results demonstrate that this electrostatic/hydrogen bond switch turns the phosphate of PA into an effective and preferred docking site for lysine and arginine residues. In combination with the special packing properties of PA, PA may well be nature's preferred membrane lipid for interfacial insertion of positively charged membrane protein domains.
- Published
- 2007
- Full Text
- View/download PDF
46. Phase III trial of gabapentin alone or in conjunction with an antidepressant in the management of hot flashes in women who have inadequate control with an antidepressant alone: NCCTG N03C5.
- Author
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Loprinzi CL, Kugler JW, Barton DL, Dueck AC, Tschetter LK, Nelimark RA, Balcueva EP, Burger KN, Novotny PJ, Carlson MD, Duane SF, Corso SW, Johnson DB, and Jaslowski AJ
- Subjects
- Adult, Aged, Aged, 80 and over, Drug Therapy, Combination, Female, Gabapentin, Humans, Middle Aged, Treatment Outcome, Amines therapeutic use, Anticonvulsants therapeutic use, Antidepressive Agents therapeutic use, Cyclohexanecarboxylic Acids therapeutic use, Hot Flashes drug therapy, gamma-Aminobutyric Acid therapeutic use
- Abstract
Purpose: Despite the utility of newer antidepressants for alleviating hot flashes, antidepressants do not work adequately enough in many patients. Gabapentin is a nonhormonal agent that also can reduce hot flashes. No data have been available to address whether the combination of both agents would more effectively alleviate hot flashes, compared with gabapentin alone, in patients with inadequate hot flash control with an antidepressant alone., Patients and Methods: This was a randomized trial in which 118 patients with inadequate hot flash control on an antidepressant were randomly assigned to receive both an antidepressant and gabapentin versus being weaned off the antidepressant and receiving gabapentin alone. Patients were observed for 5 weeks (including a baseline week in which patients continued on their current antidepressant without gabapentin) during which time they completed validated daily hot flash diaries., Results: Ninety-one patients provided complete data at the 5-week assessment. Regardless of whether or not the antidepressant was continued when gabapentin was started, there was an approximately 50% median reduction in hot flash frequencies (54%; 95% CI, 34% to 70% for combined treatment v 49%; 95% CI, 26% to 58% for gabapentin alone) and scores (56%; 95% CI, 26% to 71% for combined treatment v 60%; 95% CI, 33% to 73% for gabapentin alone)., Conclusion: Gabapentin seems to decrease hot flashes by approximately 50% in women with inadequate hot flash control who were using an antidepressant. This study saw no significant additional hot flash reduction from continuation of the antidepressant.
- Published
- 2007
- Full Text
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47. Actin filaments are involved in the maintenance of Golgi cisternae morphology and intra-Golgi pH.
- Author
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Lázaro-Diéguez F, Jiménez N, Barth H, Koster AJ, Renau-Piqueras J, Llopis JL, Burger KN, and Egea G
- Subjects
- Actin Cytoskeleton drug effects, Animals, Botulinum Toxins pharmacology, Bridged Bicyclo Compounds, Heterocyclic pharmacology, Chlorocebus aethiops, Cytochalasin D pharmacology, Epithelial Cells physiology, Fluorescent Antibody Technique, Indirect, Golgi Apparatus drug effects, HeLa Cells, Humans, Hydrogen-Ion Concentration, Kidney cytology, Marine Toxins pharmacology, Nucleic Acid Synthesis Inhibitors pharmacology, Oxazoles pharmacology, Poly(ADP-ribose) Polymerases pharmacology, Thiazolidines pharmacology, Vero Cells drug effects, Vero Cells ultrastructure, Actin Cytoskeleton metabolism, Golgi Apparatus metabolism
- Abstract
Here we examine the contribution of actin dynamics to the architecture and pH of the Golgi complex. To this end, we have used toxins that depolymerize (cytochalasin D, latrunculin B, mycalolide B, and Clostridium botulinum C2 toxin) or stabilize (jasplakinolide) filamentous actin. When various clonal cell lines were examined by epifluorescence microscopy, all of these actin toxins induced compaction of the Golgi complex. However, ultrastructural analysis by transmission electron microscopy and electron tomography/three-dimensional modelling of the Golgi complex showed that F-actin depolymerization first induces perforation/fragmentation and severe swelling of Golgi cisternae, which leads to a completely disorganized structure. In contrast, F-actin stabilization results only in cisternae perforation/fragmentation. Concomitantly to actin depolymerization-induced cisternae swelling and disorganization, the intra-Golgi pH significantly increased. Similar ultrastructural and Golgi pH alkalinization were observed in cells treated with the vacuolar H+ -ATPases inhibitors bafilomycin A1 and concanamycin A. Overall, these results suggest that actin filaments are implicated in the preservation of the flattened shape of Golgi cisternae. This maintenance seems to be mediated by the regulation of the state of F-actin assembly on the Golgi pH homeostasis., (Copyright 2006 Wiley-Liss, Inc.)
- Published
- 2006
- Full Text
- View/download PDF
48. Aclar discs: a versatile substrate for routine high-pressure freezing of mammalian cell monolayers.
- Author
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Jiménez N, Humbel BM, van Donselaar E, Verkleij AJ, and Burger KN
- Subjects
- Animals, Caco-2 Cells, Freeze Substitution, HeLa Cells, Humans, Pressure, Cryopreservation instrumentation, Cryopreservation methods
- Abstract
High-pressure freezing avoids the artefacts induced by conventional chemical fixation, and, in combination with freeze-substitution and plastic embedding, is a reliable method for the ultrastructural analysis of mammalian cell monolayers. In order to high-pressure freeze mammalian cell monolayers, cells have to be seeded on a suitable substrate. Unfortunately, electron microscopy analysis is often hampered by poor cell growth, changes in cell morphology induced by the cell substrate or cell loss during processing. We report a method to culture, high-pressure freeze, freeze-substitute and plastic embed mammalian cell monolayers. The method is based on the use of Aclar, a copolymer film with properties very similar to those of tissue culture plastic. We show that Aclar discs support the normal growth and morphology of a wide variety of mammalian cell types, and form an ideal starting point for high-pressure freezing, freeze-substitution and plastic embedding. We present a complete protocol, which, because of its simplicity and reproducibility, provides a method suitable for the routine analysis of mammalian cell monolayers by electron microscopy and tomography.
- Published
- 2006
- Full Text
- View/download PDF
49. What makes the bioactive lipids phosphatidic acid and lysophosphatidic acid so special?
- Author
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Kooijman EE, Carter KM, van Laar EG, Chupin V, Burger KN, and de Kruijff B
- Subjects
- Cell Membrane chemistry, Endoplasmic Reticulum chemistry, Hydrogen Bonding, Hydrogen-Ion Concentration, Intracellular Membranes chemistry, Ions chemistry, Least-Squares Analysis, Magnetic Resonance Spectroscopy, Molecular Structure, Phosphatidylcholines chemistry, Phosphatidylethanolamines chemistry, Protons, Titrimetry, Lipid Bilayers chemistry, Lysophospholipids chemistry, Membranes, Artificial, Models, Molecular, Phosphatidic Acids chemistry
- Abstract
Phosphatidic acid and lysophosphatidic acid are minor but important anionic bioactive lipids involved in a number of key cellular processes, yet these molecules have a simple phosphate headgroup. To find out what is so special about these lipids, we determined the ionization behavior of phosphatidic acid (PA) and lysophosphatidic acid (LPA) in extended (flat) mixed lipid bilayers using magic angle spinning 31P NMR. Our data show two surprising results. First, despite identical phosphomonoester headgroups, LPA carries more negative charge than PA when present in a phosphatidylcholine bilayer. Dehydroxy-LPA [1-oleoyl-3-(phosphoryl)propanediol] behaves in a manner identical to that of PA, indicating that the difference in negative charge between LPA and PA is caused by the hydroxyl on the glycerol backbone of LPA and its interaction with the phosphomonoester headgroup. Second, deprotonation of phosphatidic acid and lysophosphatidic acid was found to be strongly stimulated by the inclusion of phosphatidylethanolamine in the bilayer, indicating that lipid headgroup charge depends on local lipid composition and will vary between the different subcellular locations of (L)PA. Our findings can be understood in terms of a hydrogen bond formed within the phosphomonoester headgroup of (L)PA and its destabilization by competing intra- or intermolecular hydrogen bonds. We propose that this hydrogen bonding property of (L)PA is involved in the various cellular functions of these lipids.
- Published
- 2005
- Full Text
- View/download PDF
50. Membrane activity of the phospholipase C-delta1 pleckstrin homology (PH) domain.
- Author
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Flesch FM, Yu JW, Lemmon MA, and Burger KN
- Subjects
- Animals, Binding Sites, Cattle, Cell Membrane chemistry, Phosphatidylcholines metabolism, Phosphatidylinositol 4,5-Diphosphate metabolism, Phosphatidylinositol Phosphates metabolism, Phosphatidylserines metabolism, Phospholipase C delta, Protein Binding, Protein Structure, Tertiary, Rats, Substrate Specificity, Cell Membrane metabolism, Isoenzymes chemistry, Isoenzymes metabolism, Type C Phospholipases chemistry, Type C Phospholipases metabolism
- Abstract
PH-PLCdelta1 [the PH domain (pleckstrin homology domain) of PLCdelta1 (phospholipase C-delta1)] is among the best-characterized phosphoinositide-binding domains. PH-PLCdelta1 binds with high specificity to the headgroup of PtdIns(4,5)P2, but little is known about its interfacial properties. In the present study, we show that PH-PLCdelta1 is also membrane-active and can insert significantly into PtdIns(4,5)P2-containing monolayers at physiological (bilayer-equivalent) surface pressures. However, this membrane activity appears to involve interactions distinct from those that target PH-PLCdelta1 to the PtdIns(4,5)P2 headgroup. Whereas the majority of PtdIns(4,5)P2-bound PH-PLCdelta1 can be displaced by adding excess of soluble headgroup [Ins(1,4,5)P3], membrane activity of PH-PLCdelta1 cannot. PH-PLCdelta1 differs from other phosphoinositide-binding domains in that its membrane insertion does not require that the phosphoinositide-binding site be occupied. Significant monolayer insertion remains when the phosphoinositide-binding site is mutated, and PH-PLCdelta1 can insert into monolayers that contain no PtdIns(4,5)P2 at all. Our results suggest a model in which reversible membrane binding of PH-PLCdelta1, mediated by PtdIns(4,5)P2 or other acidic phospholipids, occurs without membrane insertion. Accumulation of the PH domain at the membrane surface enhances the efficiency of insertion, but does not significantly affect its extent, whereas the presence of phosphatidylethanolamine and cholesterol in the lipid mixture promotes the extent of insertion. This is the first report of membrane activity in an isolated PH domain and has implications for understanding the membrane targeting by this common type of domain.
- Published
- 2005
- Full Text
- View/download PDF
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