Search

Poly(ADP-ribose) polymerase (PARP) inhibitors represent one of the successful novel approaches to targeted cancer treatment. Indeed, the US Food and Drug Administration (FDA) has recently approved PARP inhibitors for the treatment of breast and ovarian cancers. Despite the proven efficacy of these agents, certain challenges remain with their use. Among the most important are primary and secondary resistance. Here, we review the mechanism of action of PARP inhibitors and their ability to exploit certain inherent deficiencies among malignant cells to improve cell killing, with a focus on deficiencies in homologous recombination among cells with BRCA1 and BRCA2 mutations. Moreover, we discuss the different mechanisms of resistance including development of secondary resistance and strategies to overcome them. Finally, we discuss the limitations of novel therapeutic interventions and possible future studies to exploit biochemical pathways in order to improve therapeutic efficacy of PARP inhibitors.

Background Chemotherapy-induced peripheral neuropathy is not only one of the most common causes of dose reduction or discontinuation of cancer treatment, but it can also permanently decrease the quality of life of cancer patients and survivors. Notably, Sirt2 protects many organs from various injuries, including diabetic peripheral neuropathy. As demonstrated previously by our laboratory and others, the overexpression of Sirt2 can improve cisplatin-induced neuropathy, although the mechanism is still unclear. Results In this study, the underlying mechanism by which Sirt2 protects neurons from cisplatin-induced injury was explored using the RNAseq technique in cultured rodent neurons. Sirt2 status was modified by genetic knockout (Sirt2/KO) and was then reconstituted in Sirt2/KO cells (Sirt2/Res). We observed 323 upregulated genes and 277 downregulated genes in Sirt2-expressing cells (Sirt2/Res) compared to Sirt2-deficient cells (Sirt2/KO). Pathway analysis suggested that Sirt2 may affect several pathways, such as MAPK, TNF, and cytokine–cytokine interaction. Furthermore, cisplatin-induced changes to the transcriptome are strongly associated with Sirt2 status. Cisplatin induced distinctive transcriptome changes for 227 genes in Sirt2-expressing cells and for 783 genes in Sirt2-deficient cells, while changes in only 138 of these genes were independent of Sirt2 status. Interestingly, changes in the p53 pathway, ECM–receptor interactions, and cytokine–cytokine receptor interactions were induced by cisplatin only in Sirt2-deficient cells. Conclusions This study demonstrated that Sirt2 regulates the transcriptome in cultured rodent neuronal cells. Furthermore, Sirt2-associated transcriptome regulation may be an important mechanism underlying the role of Sirt2 in organ protection, such as in cisplatin-induced neuronal injury. Sirt2 may be a potential target for the prevention and treatment of chemotherapy-induced neuropathy.

SIRT2, an NAD+-dependent histone deacetylase, has been shown to play a pivotal role in various physiological processes, however, its role in cancer is currently controversial. In recent years, SIRT2 has been described as both a tumor suppressor and oncogene with divergent expression and function in various malignancies. Using murine allograft melanoma models, our results suggest increased systemic expression of SIRT2 promotes tumor progression. In this study, SIRT2-overexpressing mice exhibited enhanced tumor growth and larger tumor volumes compared to their wild-type littermates. Mechanistically, systemic overexpression of SIRT2 reduces the number of tumor-infiltrating natural killer (NK) cells and suppresses NK cell function and proliferation within the tumor microenvironment (TME). Furthermore, despite the enhancing effect of NK cell depletion on tumor volume and growth rate in wild-type littermate mice, this effect was diminished in SIRT2-overexpressing mice. Lastly, pharmacological inhibition of SIRT2 increases NK cell tumor infiltration and suppresses allograft melanoma tumor growth. The findings of this study identify a dynamic functional interaction between systemic SIRT2 and NK cell activity, which controls melanoma tumor progression. Given the recent renewed interest in NK-cell-mediated immunotherapy response, SIRT2 could present a new opportunity to mediate immunotherapy response and resistance.

Glucopyranosyl-conjugated benzyl derivatives containing a [1,2,3]-triazole linker were synthesized. Benzyl served as an important pharmacophore in anti-cancer compounds. Compound 8d inhibited the proliferation of colorectal cancer cells with the potency comparable to 5-fluorouracil (5-FU) with improved selectivity towards cancer cells. The antiproliferative activity of 8d is achieved through triggering apoptotic cell death.

Obstructive sleep apnea (OSA), a common sleep disorder disease, affects millions of people. Without appropriate treatment, this disease can provoke several health-related risks including stroke and sudden death. A variety of treatments have been introduced to relieve OSA. The main present clinical treatments and undertaken research activities to improve the success rate of OSA were covered in this paper. Additionally, guidelines on choosing a suitable treatment based on scientific evidence and objective comparison were provided. This review paper specifically elaborated the clinically offered managements as well as the research activities to better treat OSA. We analyzed the methodology of each diagnostic and treatment method, the success rate, and the economic burden on the world. This review paper provided an evidence-based comparison of each treatment to guide patients and physicians, but there are some limitations that would affect the comparison result. Future research should consider the consistent follow-up period and a sufficient number of samples. With the development of implantable medical devices, hypoglossal nerve stimulation systems will be designed to be smart and miniature and one of the potential upcoming research topics. The transcutaneous electrical stimulation as a non-invasive potential treatment would be further investigated in a clinical setting. Meanwhile, no treatment can cure OSA due to the complicated etiology. To maximize the treatment success of OSA, a multidisciplinary and integrated management would be considered in the future.

Purpose/Objective(s) SIRT2, an NAD+-dependent histone deacetylase, has been shown to play a pivotal role in various physiological processes, however, its role in cancer is currently controversial. In recent years, SIRT2 has been described as both a tumor suppressor and oncogene with divergent expression and function in various malignancies. With established roles in inflammation and glucose and iron metabolism, systemic and microenvironment SIRT2, rather than just intrinsic tumor cell expression, might have implications in tumor progression. Moreover, recent interest in the tumor immune microenvironment has further characterized immune cells involved in tumor suppression, including natural killer (NK) cells. Here, we sought to investigate the biological role of systemic SIRT2 in melanoma tumor progression and to evaluate its interaction with key tumor suppressive immune cells. Materials/Methods Murine models were employed to investigate the effect of systemic SIRT2 on melanoma tumor progression. Tumor progression was measured in terms of weight and volume for 20 days following subcutaneous inoculation of Sirt2-KI and WT mice with B16-F10 melanoma cells. Differences in tumor-infiltrating immune cell composition were determined by flow cytometry. Granzyme B and Ki-67 immunohistochemical staining was used to measure NK cell functional activity and proliferation in in vivo melanoma samples. NK cell function was further evaluated using in vitro and ex vivo mouse models as well as an in vitro human model. Antibody-mediated NK cell depletion established NK cells as an integral player in SIRT2-mediated tumor promotion. Finally, SIRT2 was pharmacologically inhibited by SirReal2, and the effect on melanoma progression and NK cell tumor infiltration was established. Results Increased systemic expression of SIRT2 promoted melanoma progression in mice, resulting in larger and heavier tumors. Mechanistically, systemic SIRT2 overexpression reduced the number of tumor-infiltrating NK cells and suppressed NK cell activation and proliferation within the tumor microenvironment. Furthermore, despite the effect of increased tumor growth rate and tumor volume in wild-type littermate mice, NK cell depletion did not affect that in SIRT2-overexpressing mice. Lastly, pharmacological inhibition of SIRT2 increased NK cell tumor infiltration and suppressed melanoma tumor growth. Conclusion Systemic SIRT2 and NK cell activity exhibit a dynamic functional interaction which promotes melanoma tumor progression. Given the recent renewed interest in NK-cell-mediated immunotherapy response, SIRT2 could represent a new opportunity to mediate immunotherapy response and resistance.

Chemotherapy-induced peripheral neuropathy is among the most common dose-limiting adverse effects of cancer treatment, leading to dose reduction and discontinuation of life-saving chemotherapy and a permanently impaired quality of life for patients. Currently, no effective treatment or prevention is available. Senescence induced during cancer treatment has been shown to promote the adverse effects. Here, we show that cisplatin induces senescent-like neuronal cells in primary culture and in mouse dorsal root ganglia (DRG), as determined by the characteristic senescence markers including senescence-associated beta-galactosidase, accumulation of cytosolic p16INK4A and HMGB1, as well as increased expression of p16Ink4a, p21, and MMP-9. The accumulation of senescent-like neuronal cells in DRG is associated with cisplatin-induced peripheral neuropathy (CIPN) in mice. To determine if depletion of senescent-like neuronal cells may effectively mitigate CIPN, we used a pharmacological ‘senolytic’ agent, ABT263, which inhibits the anti-apoptotic proteins BCL-2 and BCL-xL and selectively kills senescent cells. Our results demonstrated that clearance of DRG senescent neuronal cells reverses CIPN, suggesting that senescent-like neurons play a role in CIPN pathogenesis. This finding was further validated using transgenic p16-3MR mice, which permit ganciclovir (GCV) to selectively kill senescent cells expressing herpes simplex virus 1 thymidine kinase (HSV-TK). We showed that CIPN was alleviated upon GCV administration to p16-3MR mice. Together, the results suggest that clearance of senescent DRG neuronal cells following platinum-based cancer treatment might be an effective therapy for the debilitating side effect of CIPN.

Background Noninvasive monitoring of fetal development and the early detection of pregnancy-associated complications is challenging, largely due to the lack of information about the molecular spectrum during pregnancy. Recently, cell-free DNA in plasma was found to reflect the global nucleosome footprint and status of gene expression, and showed potential for noninvasive health monitoring during pregnancy. Objective(s) We aimed to test the relationships between plasma cell-free DNA profiles and pregnancy biology, and evaluate the use of cell-free DNA profile as a non-invasive method for physiological and pathological status monitoring during pregnancy. Study Design We used genome cell-free DNA sequencing data generated from non-invasive prenatal testing in a total of 2937 pregnant women. For each physiological and pathological conditions, features of cell-free DNA profile were identified using the discovery cohort, and support vector machines classifiers were built and evaluated using independent training and validation cohorts. Results We established nucleosome occupancy profiles at transcription start sites in different gestational trimesters, demonstrated the relationships between gene expression and cell-free DNA coverage at transcription start sites, and showed that the cell-free DNA profiles at transcription start sites represented the biological processes of pregnancy. In addition, using cell-free DNA data, nucleosome profiles of transcription factor binding sites were identified to reflect transcription factor footprint, which may help to reveal the molecular mechanisms underlying pregnancy. Finally, by using machine learning models on low coverage non-invasive prenatal testing data, we evaluated the use of cell-free DNA nucleosome profiles for distinguishing gestational trimesters, fetal gender, and fetal trisomy 21, and highlighted its potential utility for predicting physiological and pathological fetal conditions by using low coverage non-invasive prenatal testing data. Conclusion(s) Our analyses profiled nucleosome footprints and regulatory networks during pregnancy and established a noninvasive, proof-of-principle methodology for health monitoring during pregnancy.

Background: Radio-, chemo- and chemoradio-therapy are essential strategies for cancer therapy. However, there are no reliable non-invasive methods for assessing the effectiveness of these therapies before treatment. Recently, plasma cell-free DNA (cfDNA) was found to reflect the global nucleosome footprint and gene expression status of cancer and immune cells in cancer patients. Therefore, we hypothesized that cfDNA could be used to evaluate the effectiveness of cancer therapy. Methods: In this study, we implemented whole genome sequencing (WGS) of cfDNA collected from patients with three types of cancer before therapy. In addition to promoter profiling, we found that the global chromatin profiles between the sensitive and non-sensitive groups of each cancer type also showed significant changes. To further compare their potentials for effectiveness evaluation of cancer therapy, we developed classifiers based on the WGS data derived from 194 locally advanced rectal cancer (LARC) patients with multiple machine learning models for identifying LARC with pathological complete response (pCR). Findings: We found that not only the promoter profiling but also some variables of global chromatin profiles of cfDNA between the sensitive and non-sensitive groups of cancer patients showed significant difference. By comparing their performance for effectiveness evaluation, we found that the predictive classifier based on promoter profiling with the SVM model (PPCET) had the largest AUC of 0.89 (95% CI 0.83-0.94), which may highlight the potential applications of promoter profiling as a novel non-invasive in vivo approach for assessing the effectiveness of cancer therapy. Interpretation: PPCET is a non-invasive technique for predicting the effectiveness of cancer therapy before treatment that may help to prevent indiscriminate use of drugs, reduce toxicity and side effects, and improve the curative effect and quality of life. Funding Statement: This work was supported by National Natural Science Foundation of China [81802435]; China Postdoctoral Science Foundation funded project [2019T120742, 2016M602486]; Natural Science Foundation of Guangdong Province [2018A030313286, 2015B020233009]; Science and Technology Program of Guangzhou [201604020104, 201803040009]. Declaration of Interests: The authors declare that they have no conflicts of interest. Ethics Approval Statement: All plasma samples were obtained under Institutional Review Board approved protocols with informed consent from all participants for research use.

PARP inhibitors (PARPi) are potentially effective therapeutic agents capable of inducing synthetic lethality in tumors with deficiencies in homologous recombination (HR)-mediated DNA repair such as those carrying BRCA1 mutations. However, BRCA mutations are rare, the majority of tumors are proficient in HR repair, and thus most tumors are resistant to PARPi. Previously, we observed that ionizing radiation (IR) initiates cytoplasmic translocation of BRCA1 leading to suppression of HR-mediated DNA repair and induction of synthetic PARPi lethality in wild-type BRCA1 and HR-proficient tumor cells. The tumor suppressor p53 was identified as a key factor that regulates DNA damage–induced BRCA1 cytoplasmic sequestration following IR. However, the role of p53 in IR-induced PARPi sensitization remains unclear. This study elucidates the role of p53 in IR-induced PARPi cytotoxicity in HR-proficient cancer cells and suggests p53 status may help define a patient population that might benefit from this treatment strategy. Sensitization to PARPi following IR was determined in vitro and in vivo utilizing human breast and glioma tumor cells carrying wild-type BRCA1 and p53, and in associated cells in which p53 function was modified by knockdown or mutation. In breast and glioma cells with proficient HR repair, IR-induced BRCA1 cytoplasmic sequestration, HR repair inhibition, and subsequent PARPi sensitization in vitro and in vivo was dependent upon functional p53. Implications: Implications: p53 status determines PARP inhibitor sensitization by ionizing radiation in multiple BRCA1 and HR-proficient tumor types and may predict which patients are most likely to benefit from combination therapy. Mol Cancer Res; 16(7); 1092–102. ©2018 AACR.

Highlights • Summarizes photoacoustic imaging for monitoring of stroke diseases. • Focuses on the potential photoacoustic systems for human monitoring. • Reports the challenges of stroke monitoring in the human brain., Stroke is the leading cause of death and disability after ischemic heart disease. However, there is lacking a non-invasive long-time monitoring technique for stroke diagnosis and therapy. The photoacoustic imaging approach reconstructs images of an object based on the energy excitation by optical absorption and its conversion to acoustic waves, due to corresponding thermoelastic expansion, which has optical resolution and acoustic propagation. This emerging functional imaging method is a non-invasive technique. Due to its precision, this method is particularly attractive for stroke monitoring purpose. In this paper, we review the achievements of this technology and its applications on stroke, as well as the development status in both animal and human applications. Also, various photoacoustic systems and multi-modality photoacoustic imaging are introduced as for potential clinical applications. Finally, the challenges of photoacoustic imaging for monitoring stroke are discussed.

Effect of laparoscopic myomectomy on the serum levels of interleukin-6 (IL-6) and total antioxidant capacity (TAC), and the ovarian function of patients with uterine fibroids was studied. Ninety patients with uterine fibroids admitted to The Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, from March 2013 to July 2014, were randomly divided into the experimental group (n=45) and the control group (n=45). The experimental group was treated with laparoscopic myomectomy, and the control group was treated with abdominal myomectomy. ELISA was used for detecting IL-6 and TAC content. Radioimmunoassay (RIA) was used for detecting serum ovarian function indicators, including estradiol (E2), follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Patients in the experimental group had significantly lower intraoperative blood loss, postoperative exhaust time, number of days to recovery and return to work, number of intraoperative fibroids removed, and length of stay than those in the control group (P

PARP inhibitors are one of the success stories of targeted cancer therapy. In the last few years, these drugs have been approved by the US Food and Drug Administration (FDA) for the treatment of breast and ovarian cancers. PARP inhibitors are useful in the treatment of DNA double-strand break repair deficient tumors such as those with BRCA1 or BRCA2 mutations. In this chapter, we discuss the pathophysiology of breast and ovarian cancers in association with DNA repair and genomic instability. We focus our discussion on the use of PARP inhibitors in these malignancies. We also discuss how the tumors gain resistance to these agents, including utilizing strategies such as restoration of homologous recombination-mediated DNA double-strand break repair pathway and stabilization of replication forks. We review possible approaches for overcoming resistance to PARP inhibitors including targeting protein kinases and alternate signaling pathways, exploiting cell cycle regulation, and drug pumps. We end with the benefits of novel therapies, their limitations and work that remains to be done.

SIRT2, an NAD+-dependent histone deacetylase, has been shown to play a pivotal role in various physiological processes, however, its role in cancer is currently controversial. In recent years, SIRT2 has been described as both a tumor suppressor and oncogene with divergent expression and function in various malignancies. Using murine xenograft melanoma models, our results suggest increased systemic expression of SIRT2 promotes tumor progression. In this study, SIRT2-overexpressing mice exhibited enhanced tumor growth and larger tumor volumes compared to their wild-type littermates. Mechanistically, systemic overexpression of SIRT2 reduces the number of tumor-infiltrating natural killer (NK) cells and suppresses NK cell activation and proliferation within tumor microenvironment (TME). Furthermore, despite the effect of increased tumor growth rate and tumor volume in wild-type littermate mice, NK cell depletion does not affect that in SIRT2-overexpressing mice. Lastly, pharmacological inhibition of SIRT2 increases NK cell tumor infiltration and suppresses melanoma tumor growth in mice. The findings of this study identify a dynamic functional interaction between systemic SIRT2 and NK cell activity, which promotes melanoma tumor progression. Given the recent renewed interest in NK-cell-mediated immunotherapy response, SIRT2 could present a new opportunity to mediate immunotherapy response and resistance. Citation Format: Fen Xia. Sirt2: A tumor suppressor or promotor? [abstract]. In: Proceedings of the AACR Virtual Special Conference on Radiation Science and Medicine; 2021 Mar 2-3. Philadelphia (PA): AACR; Clin Cancer Res 2021;27(8_Suppl):Abstract nr IA-024.

Platinum-based chemotherapy-induced peripheral neuropathy (CIPN) is one of the most common dose-limiting effects of cancer treatment and results in dose reduction and discontinuation of life-saving chemotherapy. Its debilitating effects are often permanent and lead to lifelong impairment of quality of life in cancer patients. While the mechanisms underlying the toxicity are not yet fully defined, dorsal root ganglia sensory neurons play an integral role in symptom development. DNA-platinum adducts accumulate in these cells and inhibit normal cellular function. Nucleotide excision repair (NER) is integral to the repair of platinum adducts, and proteins involved in its mechanism serve as potential targets for future therapeutics. This review aims to highlight NER’s role in cisplatin-induced peripheral neuropathy, summarize current clinical approaches to the toxicity, and discuss future perspectives for the prevention and treatment of CIPN.

Resistance to genotoxic therapies is a primary cause of treatment failure and tumor recurrence. The underlying mechanisms that activate the DNA damage response (DDR) and allow cancer cells to escape the lethal effects of genotoxic therapies remain unclear. Here, we uncover an unexpected mechanism through which pyruvate kinase M2 (PKM2), the highly expressed PK isoform in cancer cells and a master regulator of cancer metabolic reprogramming, integrates with the DDR to directly promote DNA double-strand break (DSB) repair. In response to ionizing radiation and oxidative stress, ATM phosphorylates PKM2 at T328 resulting in its nuclear accumulation. pT328-PKM2 is required and sufficient to promote homologous recombination (HR)-mediated DNA DSB repair through phosphorylation of CtBP-interacting protein (CtIP) on T126 to increase CtIP's recruitment at DSBs and resection of DNA ends. Disruption of the ATM-PKM2-CtIP axis sensitizes cancer cells to a variety of DNA-damaging agents and PARP1 inhibition. Furthermore, increased nuclear pT328-PKM2 level is associated with significantly worse survival in glioblastoma patients. Combined, these data advocate the use of PKM2-targeting strategies as a means to not only disrupt cancer metabolism but also inhibit an important mechanism of resistance to genotoxic therapies.

Platinum-based chemotherapy–induced peripheral neuropathy is one of the most common causes of dose reduction and discontinuation of life-saving chemotherapy in cancer treatment; it often causes permanent impairment of quality of life in cancer patients. The mechanisms that underlie this neuropathy are not defined, and effective treatment and prevention measures are not available. Here, we demonstrate that SIRT2 protected mice against cisplatin-induced peripheral neuropathy (CIPN). SIRT2 accumulated in the nuclei of dorsal root ganglion sensory neurons and prevented neuronal cell death following cisplatin treatment. Mechanistically, SIRT2, an NAD(+)-dependent deacetylase, protected neurons from cisplatin cytotoxicity by promoting transcription-coupled nucleotide excision repair (TC-NER) of cisplatin-induced DNA cross-links. Consistent with this mechanism, pharmacological inhibition of NER using spironolactone abolished SIRT2-mediated TC-NER activity in differentiated neuronal cells and protection of neurons from cisplatin-induced cytotoxicity and CIPN in mice. Importantly, SIRT2’s protective effects were not evident in lung cancer cells in vitro or in tumors in vivo. Taken together, our results identified SIRT2’s function in the NER pathway as a key underlying mechanism of preventing CIPN, warranting future investigation of SIRT2 activation–mediated neuroprotection during platinum-based cancer treatment.

Methionine dependency describes the characteristic rapid in vitro death of most tumor cells in the absence of methionine. Combining chemotherapy with dietary methionine deprivation [methionine-deficient diet (MDD)] at tolerable levels has vast potential in tumor treatment; however, it is limited by MDD-induced toxicity during extended deprivation. Recent advances in imaging and irradiation delivery have created the field of stereotactic body radiotherapy (SBRT), where fewer large-dose fractions delivered in less time result in increased local-tumor control, which could be maximally synergistic with an MDD short course. Identification of the lowest effective methionine dietary intake not associated with toxicity will further enhance the cancer therapy potential. In this study, we investigated the effects of MDD and methionine-restricted diet (MRD) in primary and metastatic melanoma models in combination with radiotherapy (RT). In vitro, MDD dose-dependently sensitized mouse and human melanoma cell lines to RT. In vivo in mice, MDD substantially potentiated the effects of RT by a significant delay in tumor growth, in comparison with administering MDD or RT alone. The antitumor effects of an MDD/RT approach were due to effects on one-carbon metabolism, resulting in impaired methionine biotransformation via downregulation of Mat2a, which encodes methionine adenosyltransferase 2A. Furthermore, and probably most importantly, MDD and MRD substantially diminished metastatic potential; the antitumor MRD effects were not associated with toxicity to normal tissue. Our findings suggest that modulation of methionine intake holds substantial promise for use with short-course SBRT for cancer treatment.

Idiopathic asthenospermia is the most common type of male infertility. Although the mechanisms causing asthenospermia are complex, recent studies have indicated an important role of cation channel of sperm (CATSPER) gene downregulation or abnormality in the etiology of idiopathic asthenospermia. In the present study, 192 patients with idiopathic asthenospermia and 288 healthy controls were enrolled, and a flight mass spectrometry using Sequenom’s MassArray biochip system was applied for genotyping 16 CATSPER gene SNPs reported in the human single nucleotide polymorphism (SNP) database. Our results indicated a correlation between CATSPER1 SNPs and idiopathic asthenospermia. In particular, the exonal SNP rs1893316 in CATSPER1 significantly correlated with idiopathic asthenospermia risk and is a potential important factor in determining an individual’s genetic susceptibility to idiopathic asthenospermia. These finding will help to further elucidate the role of CATSPER1 in idiopathic asthenospermia pathogenesis.

Exposure to high levels of estrogen is considered an important risk factor for susceptibility to breast cancer. Common polymorphisms in genes that affect estrogen levels may be associated with breast cancer risk, but no comprehensive study has been performed among Han Chinese women. In the present study, 32 single-nucleotide polymorphisms (SNPs) in estrogen-related genes were genotyped using the MassARRAY IPLEX platform in 1076 Han Chinese women. Genotypic and allelic frequencies were compared between case and control groups. Unconditional logistic regression was used to assess the effects of SNPs on breast cancer risk. Associations were also evaluated for breast cancer subtypes stratified by estrogen receptor (ER) and progesterone receptor (PR) status. Case-control analysis showed a significant relation between heterozygous genotypes of rs700519 and rs2069522 and breast cancer risk (OR = 0.723, 95% CI = 0.541–0.965, p = 0.028 and OR = 1.500, 95% CI = 1.078–2.087, p = 0.016, respectively). Subgroup comparisons revealed that rs2446405 and rs17268974 were related to ER status, and rs130021 was associated with PR status. Our findings suggest that rs700519 and rs2069522 are associated with susceptibility to breast cancer among the Han Chinese population and have a cumulative effect with three other identified SNPs. Further genetic and functional studies are needed to identify additional SNPs, and to elucidate the underlying molecular mechanisms.

Introduction Although tumor metastases remain significant drivers of mortality, the genetic factors that increase the risks of metastases are not fully identified. Interleukin 6 (IL-6) has emerged as an important factor in breast cancer progression with IL-6 single nucleotide polymorphism (SNP) variants shown to affect survival. We hypothesized that SNPs of the IL-6 promoter at rs1800795 in breast cancer patients are associated with distant metastases. Methods We performed an initial case-control study using Vanderbilt University Medical Center's BioVU, a genomic biobank linked to de-identified electronic medical records in the Synthetic Derivative database, to identify germline SNPs that may predict the development of metastatic disease to any site from any solid tumor including breast cancer. We identified a SNP in IL-6: rs1800795 to be of significance and evaluated this finding using a separate, matched-pair cohort of breast cancer patients with and without metastases from The Ohio State University Wexner Medical Center. Results The initial study suggested that GG relative to CG at rs1800795 (OR 1.52; 95% CI 1.14-2.02; p = 0.004) was significantly associated with the development of metastases. This association was also observed in the Ohio State University cohort (OR 2.23; 95% CI 1.06-4.71; p = 0.001). There were no significant relationships between rs1800795 status and any patient or tumor characteristics, including estrogen receptor status. Conclusions These findings suggest that GG SNP at IL-6: rs1800795 may indicate an increased risk of metastasis of primary breast cancer. Further studies in larger population sets are warranted as advanced screening and prophylactic intervention might be employed in GG carriers.

Optimal treatment of metastases to the central nervous system (CNS) in patients with malignant melanoma remains a clinical challenge. In particular, for patients with BRAF-mutant melanoma and CNS metastases, much remains unknown about the safety and efficacy of the novel BRAF-targeted agents when administered in close sequence with radiation. We report two cases of rapid development of CNS radiation necrosis in patients with metastatic melanoma treated with the BRAF inhibitor, vemurafenib, closely sequenced with stereotactic radiosurgery or fractionated stereotactic radiation therapy. In the absence of prospective safety data from clinical trials, we advise vigilance in monitoring patients with BRAF-mutant melanoma whose treatment plan includes CNS radiation and vemurafenib and caution when assessing treatment response within the CNS in these patients.

Recent genome-wide association studies (GWASs) have identified 15q25.1 as a lung cancer susceptibility locus. Here, we sought to explore the direct carcinogenic effects of genetic variants in this region on the risk of developing lung adenocarcinoma (ADC). Five common SNPs (rs8034191, rs16969968, rs1051730, rs938682, and rs8042374) spanning the 15q25.1 locus were assayed in a case-control study examining a cohort of 301 lung ADCs and 318 healthy controls. Stratification analysis by gender, smoking status, and tumor, node, metastasis (TNM) classification, was performed. In addition, sections from ADC tissue and normal tissue adjacent to tumors were stained with an anti-CHRNA3 (cholinergic receptor nicotinic α3) antibody by immunohistochemistry in 81 cases. Our results demonstrate that rs8042374, a variant of the CHRNA3 gene, is associated with an increased risk of ADC with an OR of 1.76 (95% CI: 1.17–2.65, p = 0.024). This variant was linked to a greater risk of ADC in female nonsmokers (OR (95% CI): 1.81 (1.05–3.12), p = 0.032) and female stage I + II cases (OR (95% CI): 1.92 (1.03–3.57), p = 0.039). Although located within the same gene, rs938682 showed protective effects for smokers, stage III + IV cases, and male stage III + IV cases. Additionally, the CHRNA3 protein level in ADC tissue was slightly higher than in the surrounding normal lung tissue, based on immunohistochemical analysis. Our results suggest that the CHRNA3 polymorphism functions as a genetic modifier of the risk of developing lung ADC in the Chinese population, particularly in nonsmoking females.

DNA damage repair plays essential roles in drug resistance, especially resistance to Poly (ADP-ribose) polymerase (PARP) inhibitors in the clinic. A subset of DNA repair proteins such as Breast cancer gene 1 (BRCA1), BRCA2 and RecA homolog (RAD51) are client proteins of heat shock protein 90 (Hsp90). Clearance of these DNA repair proteins by inhibition of Hsp90 is a promising strategy for overcoming resistance to PARP inhibitors. Here we report the pharmacological analysis of the highly potent second-generation Hsp90 inhibitor, ganetespib. Methods Nuclear BRCA1, BRCA2, and RAD51 expression in breast cancer cells were detected by subcellular fractionation and western blot analysis. Formation of nuclear RAD51 and γ-H2AX foci was analyzed by immunofluorescent staining. The cytotoxicity of ganetespib and ABT-888 in breast cancer cells were evaluated by cell proliferation, colony survival, and apoptosis assay. To investigate the efficacy of this therapy in vivo, SCID mice bearing MCF7 xenografts were treated with ganetespib and ABT-888, both as single agents and in combination. Results Ganetespib significantly destabilized nuclear BRCA1, BRCA2, and RAD51, and efficiently disrupted homologous recombination-mediated DNA double-strand break repair in breast cancer cells. The synergistic antitumor effects of ganetespib and the PARP inhibitor, ABT-888 were observed, and concurrent treatment with both inhibitors synergistically inhibited xenograft tumor growth. Importantly, the combined treatment was well tolerated, without significant loss of body weight or major histological changes in the breast cancer xenograft model. Conclusion These data provide a novel strategy for the treatment of breast cancer with wild type BRCA1 using combination therapy targeting Hsp90 to overcome resistance to PARP inhibitors.

ObjectivesTo investigate the relationships between single-nucleotide polymorphisms (SNPs) inNOTCH4and brain-derived neurotrophic factor (BDNF) with schizophrenia among Han Chinese in Southern China.MethodsTwoNOTCH4SNPs (rs520688 and rs415929) and twoBDNFSNPs (rs2030324 and rs12273539) were examined in 464 schizophrenics and 464 healthy controls from Hunan province in South China, using the Sequenom MassARRAY®iPLEX System.ResultsIn the study population, rs520688 and rs2030324 were significantly associated with schizophrenia. A decreased risk of schizophrenia was associated with the rs520688 GA genotype (p= 0.035), whereas an increased risk of schizophrenia was associated with the rs2030324 CC/CT genotype (p= 0.044). The genotype distributions of rs415929 inNOTCH4and rs12273539 inBDNFdid not differ significantly between the case and control groups. Although no allele–allele interactions were detected between rs520688 and rs2030324, recombination analysis revealed a combined effect of the two on the susceptibility to schizophrenia, with GA-TT decreasing and CT/CC-GG/GA increasing the risk of schizophrenia.ConclusionIn conclusion, rs520688 inNOTCH4and rs2030324 inBDNFare significantly associated with schizophrenia among Han Chinese in Southern China. The two had a combined effect on the susceptibility to schizophrenia among Han Chinese in Southern China, but this may not be caused by an allele–allele interaction.

In recent years, there have been multiple breakthroughs in our understanding of lung cancer biology. Despite significant advances in molecular targeted therapies, DNA-damaging cytotoxic therapies will remain the mainstay of lung cancer management for the near future. Similar to the concept of personalized targeted therapies, there is mounting evidence that perturbations in DNA repair pathways are common in lung cancers, altering the resistance of the affected tumors to many chemotherapeutics as well as radiation. Defects in DNA repair may be due to a multitude of mechanisms including gene mutations, epigenetic events, and alterations in signal transduction pathways such as epidermal growth factor receptor and phosphoinositide 3-kinase/AKT. Functional biomarkers that assess the subcellular localization of central repair proteins in response to DNA damage may prove useful for individualization of cytotoxic therapies including poly(adenosine diphosphate-ribose) polymerase inhibitors. A better mechanistic understanding of cellular sensitivity and resistance to DNA damaging agents should facilitate the development of novel, individualized treatment approaches. Absolute resistance to radiation therapy, however, does not exist. To some extent, radiation therapy will always have to remain unselective and indiscriminant to eradicate persistent, drug-resistant tumor stem cell pools.

Objective The fraction of circulating cell-free fetal (cff) DNA in maternal plasma is a critical parameter for aneuploidy screening with non-invasive prenatal testing, especially for those samples located in equivocal zones. We developed an approach to quantify cff DNA fractions directly with sequencing data, and increased cff DNAs by optimizing library construction procedure. Methods Artificial DNA mixture samples (360), with known cff DNA fractions, were used to develop a method to determine cff DNA fraction through calculating the proportion of Y chromosomal unique reads, with sequencing data generated by Ion Proton. To validate our method, we investigated cff DNA fractions of 2,063 pregnant women with fetuses who were diagnosed as high risk of fetal defects. The z-score was calculated to determine aneuploidies for chromosomes 21, 18 and 13. The relationships between z-score and parameters of pregnancies were also analyzed. To improve cff DNA fractions in our samples, two groups were established as follows: in group A, the large-size DNA fragments were removed, and in group B these were retained, during library construction. Results A method to determine cff DNA fractions was successfully developed using 360 artificial mixture samples in which cff DNA fractions were known. A strong positive correlation was found between z-score and fetal DNA fraction in the artificial mixture samples of trisomy 21, 18 and 13, as well as in clinical maternal plasma samples. There was a positive correlation between gestational age and the cff DNA fraction in the clinical samples, but no correlation for maternal age. Moreover, increased fetal DNA fractions were found in group A compared to group B. Conclusion A relatively accurate method was developed to determine the cff DNA fraction in maternal plasma. By optimizing, we can improve cff DNA fractions in sequencing samples, which may contribute to improvements in detection rate and reliability.

Estrogen receptor-a (ER) protein plays a key role in breast carcinogenesis, and common genetic variants in the corresponding gene locus have been associated with breast cancer risk in different populations. Here, we analyzed estrogen receptor 1 (ESR1) associations in two hospital-based studies of patients from the south of China. Three single-nucleotide polymorphisms (SNPs; rs3757318, rs2046210, and rs3734805) in ESR1 were selected from previous genome-wide association study results and were genotyped using the Sequenom MassARRAY® iPLEX System in 845 breast cancer patients and 882 healthy controls. Association analysis based on unconditional logistic regression was carried out to determine the odds ratio (OR) and 95% confidence interval (95%CI) for each SNP. Stratified analyses according to the status of ER and progesterone receptor (PR) were also performed. Of the three SNPs, rs3757318 did not pass the Hardy-Weinberg equilibrium test and was excluded from the subsequent analysis. The other two SNPs (rs2046210 and rs3734805) were strongly associated with susceptibility to breast cancer. Allele T of rs2046210 and allele C of rs3734805 were risk alleles and the adjusted ORs were 1.348 (95%CI = 1.172-1.550, P = 0.0001) and 1.319 (95%CI = 1.144-1.522, P = 0.0001), respectively. Furthermore, the risk allele of rs2046210 gave negative results for ER and PR expression in an immunohistochemical test, with ORs of 0.602 (95%CI = 0.384-0.944, P = 0.027) and 0.532 (95%CI = 0.338-0.837, P = 0.006), respectively. Our study further supports associations between rs2046210 and rs3734805 and breast cancer risk in Chinese women.

Genome-wide association studies (GWAS) have identified 11 loci that influence the risk of developing colorectal cancer (CRC). Given that these studies were conducted in European Caucasian populations, it is not clear whether the results are relevant for populations with different ethnicities. The aim of this study was to examine these associations in a southern Chinese population.Eleven single-nucleotide polymorphisms (SNPs), rs12701937, rs16892766, rs7014346, rs6983267, rs719725, rs10795668, rs3802842, rs4444235, rs9929218, rs10411210, and rs961253, were genotyped in 229 CRC patients and 267 controls using the MassArray SNP genotyping system.Evidence of an association with CRC was found for four of the 11 loci. The strongest associations were with rs4444235 and rs961253, with significant odds ratios close to those reported in previous GWAS. Among these four loci, rs719725 and rs4444235 were significantly associated with female gender, rs3802842, rs961253, and rs4444235 with early disease onset, and rs3802842 with later disease onset. However, no associations with CRC risk were detected for six other loci (rs9929218, rs10411210, rs12701937, rs7014346, rs6983267, and rs10795668), and one SNP, rs16892766, was not polymorphic in any of the study participants.The rs4444235 and rs961253 loci are strongly associated with the risk of CRC in southern Chinese.

A genome-wide study has shown an association between SNPs located on 17q21 and asthma. Such associations have been identified in several populations, but little is known about the Han Chinese population. We conducted a case-control study in a Han Chinese population to investigate the relationship between SNPs located on 17q21 and asthma; 241 asthmatic patients and 212 healthy controls were recruited from the outpatient clinics of the Nanfang Hospital, Guangdong Province, southern China. We genotyped six SNPs (rs8067378, rs8069176, rs2305480, rs4795400, rs12603332, and rs11650680) located on 17q21 with the Sequenom MassARRAY iPLEX platform. For two of these six loci (rs2305480 and rs8067378), there was evidence of association with asthma, and there was a weak association of asthma with rs8069176. We confirm that genetic variants on 17q21 are associated with asthma in the Han Chinese population.

The Wnt signaling pathway is crucial for pulmonary development and differentiation; dysregulation of the Wnt signaling pathway may impair lung function. Indeed, single nucleotide polymorphisms (SNPs) of Wnt pathway-related genes have been suggested as risk factors for certain types of cancers. In this study, we aimed to evaluate the influence of SNPs in Wnt-related genes (TCF2, MMP9) on susceptibility to lung cancer.Polymorphisms of TCF2 rs4430796, MMP9 rs2250889, and MMP9 rs17576 were studied in Han Chinese subjects, including 135 patients with lung cancer and 176 controls, using the Sequenom MassARRAY platform. The association of genotypes with susceptibility to lung cancer was analyzed using odds ratio (OR), with 95% confidence interval (95% CI) and χ(2).The three SNPs (rs4430796, rs2250889, and rs17576) were found to be significantly associated with an increased risk of lung cancer. The AA genotype and AG+AA genotype of rs4430796 showed a significantly increased susceptibility to lung cancer compared with the GG genotype (adjusted OR=6.03, 95% CI: 1.30-28.09, P=0.022; 5.55, 95% CI: 1.20-25.58, P=0.028). Compared with the rs17576 GG genotype, the AG and AG+AA genotypes were also associated with a significant risk (adjusted OR=2.65, 95% CI: 1.60-4.37, P≤0.001; 2.57, 95% CI: 1.59-4.19, P≤0.001) whereas the rs2250889 CG and CG+GG genotypes had 2.97-fold (95% CI: 1.81-4.85; P≤0.001) and 2.80-fold increased associations with lung cancer (95% CI: 1.73-4.54; P≤0.001), respectively, compared with the rs2250889 CC genotype. Furthermore, the association of rs4430796 with lung cancer became insignificant (P0.05) after adjusting for gender and rs2250889.The three SNPs may play a role in the predisposition of members of the Han Chinese population to lung cancer.

The epidermal growth factor receptor (EGFR) family has been implicated in several cancers, including breast, and its members have become the target of novel cancer therapies. In this report, we show a novel link between erlotinib, a potent EGFR inhibitor, DNA damage, and homology-directed recombinational repair (HDR) in human breast cancer cells. Erlotinib suppresses HDR. This is not secondary to erlotinib-mediated changes in cell cycle and is associated with increased γ-H2AX foci, which is an in situ marker of chromosomal double-strand breaks. Both Rad51 and BRCA1 are essential components of the HDR machinery. Consistent with decreased HDR in erlotinib-treated cells, erlotinib also attenuates DNA damage-induced Rad51 foci and results in cytoplasmic retention of BRCA1. As BRCA1 is a shuttling protein and its nuclear function of promoting HDR is controlled by its subcellular localization, we further show that targeted translocation of BRCA1 to the cytoplasm enhances erlotinib sensitivity. These findings suggest a novel mechanism of action of erlotinib through its effects on the BRCA1/HDR pathway. Furthermore, BRCA1/HDR status may be an innovative avenue to enhance the sensitivity of cancer cells to erlotinib. [Cancer Res 2008;68(22):9141–6]

Objective To explore the associations between urine uric acid excretion (UUAE) and diabetic retinopathy (DR)/lower limb atherosclerotic lesions in hospitalized Chinese patients with type 2 diabetes. Methods This cross-sectional study was conducted in 2529 hospitalized Chinese patients with type 2 diabetes. UUAE was determined enzymatically using a single 24-h urine collection. The subjects were stratified into quartile based on UUAE levels. DR was determined by digital fundus photography. Lower limb atherosclerotic lesions were assessed by Doppler ultrasound. Both DR and lower limb atherosclerosis were compared among the UUAE quartile groups, respectively. Results There was a significant decrease in the prevalence of DR in patients across the UUAE quartiles after adjustment for sex, age and diabetic duration (35.0%, 30.7%, 26.1%, and 21.5%, respectively, p = 0.000001 for trend). A fully adjusted multiple logistic regression analyses revealed that UUAE quartiles were markedly inversely associated with the presence of DR (p = 0.030). The prevalence of lower limb plaque (73.9% vs. 62.6%, p = 0.000044) and stenosis (16.3% vs. 9.7%, p = 0.000015) was markedly higher in the diabetics with DR than in those without DR. However, there was no statistical association between the UUAE and lower limb atherosclerotic lesions in type 2 diabetes. Conclusions Decreased UUAE was an independent risk factor for DR but not for lower limb atherosclerosis in hospitalized Chinese patients with type 2 diabetes. In selected populations, such as those with type 2 diabetes, the role of uric acid in atherosclerosis may be result from other concomitantly atherosclerotic risk factors, such as DR.

Background: Although BRCA1 has been extensively studied for its role as a tumour-suppressor protein, the role of BRCA1 subcellular localisation in oncogenesis and tumour progression has remained unclear. This study explores the impact of BRCA1 mislocalisation on clinical outcomes in breast cancer. Methods: Tissue microarrays assembled from a cohort of patients with all stages of breast cancer were analysed for BRCA1 localisation and correlated with patient survival. Tissue microarrays of patients who had breast cancer that had metastasised to the lung were assembled from an independent cohort of patients. These were analysed for BRCA1 subcellular expression. In vitro studies using cultured human breast cancer cells were conducted to examine the effect of cytosolic BRCA1 on cell migration and efficiency of invasion. Results: An inverse association was found between cytosolic BRCA1 expression and metastasis-free survival in patients aged >40 years. Further analysis of BRCA1 subcellular expression in a cohort of breast cancer patients with metastatic disease revealed that the cytosolic BRCA1 content of breast tumours that had metastasised to the lung was 36.0% (95% CI=(31.7%, 40.3%), which was markedly higher than what is reported in the literature (8.2–14.8%). Intriguingly, these lung metastases and their corresponding primary breast tumours demonstrated similarly high cytosolic BRCA1 distributions in both paired and unpaired analyses. Finally, in vitro studies using human breast cancer cells demonstrated that genetically induced BRCA1 cytosolic sequestration (achieved using the cytosol-sequestering BRCA1 5382insC mutation) increased cell invasion efficiency. Conclusions: Results from this study suggest a model where BRCA1 cytosolic mislocalisation promotes breast cancer metastasis, making it a potential biomarker of metastatic disease.

Preventing noise-induced hearing loss (NIHL) by antioxidants is based on the hypothesis that generation of reactive oxygen species is one of the causes of NIHL. alpha-Tocopherol is a naturally occurring antioxidant with no noticeable side effects. In this study, we attempted to protect guinea pigs from developing NIHL by administering alpha-tocopherol. Pigmented male guinea pigs were exposed to a noise (4 kHz octave band, 100 dB SPL), 8 h/day for 3 days consecutively. alpha-Tocopherol (10 mg/kg or 50 mg/kg daily) was given by intraperitoneal injection from 3 days before through 3 days after the noise exposure. Auditory evoked brainstem response (ABR) thresholds at 2, 4 and 8 kHz were recorded prior to the experiment, immediately post-noise, 2 and 8 days post-noise. On day 8 post-noise, after the ABR recording, guinea pigs were decapitated and the cochleae were removed for cochlear surface preparations and scanning electron microscope (SEM) study. ABR threshold shifts of groups receiving alpha-tocopherol were significantly smaller than those of groups not receiving alpha-tocopherol at all frequencies and all time points tested except that of group 3 at 8 kHz 8 days post-noise. No hair cell loss was seen on the surface preparations, but stereocilia loss was found by SEM study. The noise-induced stereocilia loss was significantly decreased by alpha-tocopherol. These results indicate that alpha-tocopherol can attenuate the noise-induced cochlear damage. Further investigations on the preventive effect of alpha-tocopherol on NIHL in noise-exposed workers are necessary.

There is an urgent need to develop new antibacterial agents because of multidrug resistance by bacteria and fungi. Schiff bases (aldehyde or ketone-like compounds) exhibit intense antibacterial characteristics, and are therefore, promising candidates as antibacterial agents. To investigate the mechanism of action of newly designed benzaldehyde Schiff bases, a series of high-yielding benzaldehyde Schiff bases were synthesized, and their structures were determined by NMR and MS spectra data. The structure-microbicidal activity relationship of derivatives was investigated, and the antibacterial mechanisms were investigated by gene assays for the expression of functional genes in vitro using Escherichia coli, Staphylococcus aureus, and Bacillus subtilis. The active compounds were selective for certain active groups. The polar substitution of the R2 group of the amino acids in the Schiff bases, affected the antibacterial activity against E. coli and S. aureus; specific active group at the R3 or R4 groups of the acylhydrazone Schiff bases could improve their inhibitory activity against these three tested organisms. The antibacterial mechanism of the active benzaldehyde Schiff bases appeared to regulate the expression of metabolism-associated genes in E. coli, hemolysis-associated genes in B. subtilis, and key virulence genes in S. aureus. Some benzaldehyde Schiff bases were bactericidal to all the three strains and appeared to regulate gene expression associated with metabolism, hemolysis, and virulence, in vitro. The newly designed benzaldehyde Schiff bases possessed unique antibacterial activity and might be potentially useful for prophylactic or therapeutic intervention of bacterial infections.

Evidence suggests that some genetic variants are risk factors for both colorectal cancer (CRC) and gastric cancer (GC). Thus, we selected 12 reported single nucleotide polymorphisms (SNPs) from genome-wide association studies of CRC and conducted this case-control study to assess the associations between these SNPs and the risk for GC in a southern Chinese population. All SNPs were genotyped in 249 individuals with GC and 292 healthy population-matched subjects using the Sequenom MassArray iPLEX System. Association analyses based on the c2 test and binary logistic regression were performed to determine the odds ratio (OR) and 95% confidence interval (95%CI) for each SNP. A stratified analysis by gender was also performed. Borderline significant associations were observed for rs4444235 (P = 0.070) and rs10411210 (P = 0.084), both fitting the overdominant model. The rs4444235 CT genotype showed a protective effect (OR = 0.72, 95%CI = 0.50-1.03), while the rs10411210 CT genotype was a risk factor (OR = 1.40, 95%CI = 0.96-2.05) as compared with the CC+TT genotype. In the female subgroup, the rs6983267 GT genotype (compared with TT, OR = 2.31, 95%CI = 1.07-4.99) and the rs10505477 CT genotype (compared with TT, OR = 2.36, 95%CI = 1.09-5.11) significantly increased the risk for GC. No significant association was detected for the other SNPs. These results provide evidence that known genetic variants associated with CRC risk may also confer risk for GC.

Sera of cancer patients may contain antibodies that react with a unique group of autologous cellular antigens called tumor-associated antigens (TAAs). The present study aimed to determine whether a mini-array of multiple TAAs would enhance antibody detection and be a useful approach in esophageal cancer detection and diagnosis. Our mini-array of multiple TAAs consisted of eleven antigens, p53, pl6, Impl, CyclinB1, C-myc, RalA, p62, Survivin, Koc, CyclinD1 and CyclinE full-length recombinant proteins. Enzyme-linked immunosorbent assays (ELISA) were used to detect autoantibodies against eleven selected TAAs in 174 sera from patients with esophageal cancer, as well as 242 sera from normal individuals. In addition, positive results of ELISA were confirmed by Western blotting. In a parallel screening trial, with the successive addition of antigen to a final total of eleven TAAs, there was a stepwise increase in positive antibody reactions. The eleven TAAs were the best parallel combination, and the sensitivity and specificity in diagnosing esophageal cancer was 75.3% and 81.0%, respectively. The positive and negative predictive values were 74.0% and 82.0%, respectively, indicating that the parallel assay of eleven TAAs raised the diagnostic precision significantly. In addition, the levels of antibodies to seven antigens, comprising p53, Impl, C-myc, RalA, p62, Survivin, and CyclinD1, were significantly different in various stages of esophageal cancer, which showed that autoantibodies may be involved in the pathogenesis and progression of esophageal cancer. All in all, this study further supports our previous hypothesis that a combination of antibodies might acquire higher sensitivity for the diagnosis of certain types of cancer. A customized mini-array of multiple carefully-selected TAAs is able to enhance autoantibody detection in the immunodiagnosis of esophageal cancer and autoantibodies to TAAs might be reference indicators of clinical stage.

The specific mechanism by which low-risk genetic variants confer breast cancer risk is currently unclear, with contradictory evidence on the role of single nucleotide polymorphisms (SNPs) in TOX3/LOC643714 as a breast cancer susceptibility locus. Investigations of this locus using a Chinese population may indicate whether the findings initially identified in a European population are generalizable to other populations, and may provide new insight into the role of genetic variants in the etiology of breast cancer. In this case-control study, 623 Chinese female breast cancer patients and 620 cancer-free controls were recruited to investigate the role of five SNPs in TOX3/LOC643714 (rs8051542, rs12443621, rs3803662, rs4784227, and rs3112612); Linkage disequilibrium (LD) pattern analysis was performed. Additionally, we evaluated how these common SNPs influence the risk of specific types of breast cancer, as defined by estrogen receptor (ER) status, progesterone receptor (PR) status and human epidermal growth factor receptor 2 (HER2) status. Significant associations with breast cancer risk were observed for rs4784227 and rs8051542 with odds ratios (OR) of 1.31 ((95% confidence intervals (CI), 1.10–1.57)) and 1.26 (95% CI, 1.02–1.56), respectively, per T allele. The T-rs8051542 allele was significantly associated with ER-positive and HER2-negative carriers. No significant association existed between rs12443621, rs3803662, and rs3112612 polymorphisms and risk of breast cancer. Our results support the hypothesis that the applicability of a common susceptibility locus must be confirmed among genetically different populations, which may together explain an appreciable fraction of the genetic etiology of breast cancer.

The tumor-suppressor breast cancer susceptibility gene 1 (BRCA1) is a nuclear-cytoplasmic shuttling protein that when in the nucleus is required for DNA repair whereas when in the cytoplasm is important in activating cell death processes. Although BRCA1 mutations have been shown to be associated with an increased risk of pancreatic ductal adenocarcinoma (PDAC), its role in disease progression is yet to be determined. We hypothesized that BRCA1 expression pattern could be used as a prognostic biomarker.Sixty-seven patients who underwent resections for PDAC were included. A tissue microarray was constructed, stained with antibodies to BRCA1, and scored for intensity and subcellular location. Univariate and multivariate statistical analyses were performed.An increase in cytosolic BRCA1 distribution was associated with higher pathologic stage (P = 0.006). Nuclear-cytosolic BRCA1 distribution was associated with a decrease in recurrence-free survival with a hazards ratio of 1.4 (P = 0.059). Decreased BRCA1 intensity was associated with higher pathologic stage (P = 0.027), but BRCA1 intensity was not associated with overall survival or recurrence-free survival.Our results demonstrate a possible association of BRCA1 expression pattern with pathologic stage, implying a potential role of BRCA1 in PDAC development and progression.

Soft tissue sarcomas (STS) are a heterogeneous group of tumors originating from mesodermal tissues such as skeletal muscle, adipose, and fibrous tissue. The propensity of STS to metastasize, particularly to the lung which occurs in approximately 20% of all cases, is the major source of mortality associated with this disease. Currently, themolecular mechanisms that drive STS metastasis are poorly understood greatly limiting our ability to determine which STS will metastasize and impeding the development of targeted therapies for the treatment of STS metastases. In this study we utilized analysis of publicly available gene expression data to identify loss of PPP2R1B expression as a strong prognosticator of STS metastasis. In vitro analyses using SW872 liposarcoma (LPS) and HT1080 fibrosarcoma cell lines determined that PPP2R1B plays an essential role in the dephosphorylation and inactivation of RALA, a major downstream effector of the Ras pathway. RALA was found to be essential for invasion of STS cells in modified Boyden chamber assays as knockdown of RALA by either siRNA or shRNA significantly decreased invasion through matrigel. Analysis of publicly available gene expression data revealed that RALA expression correlated with more aggressive LPS subtypes and was prognostic of LPS metastasis. Furthermore, we identify the transmembrane matrix metalloprotease MMP14 (MT1-MMP) as a key downstream effector of RALA mediated invasion in STS. Stable knockdown of RALA in SW872 and HT1080 cells resulted in significant mislocalization of MMP14 and reduced MMP14 enzymatic activity. MMP14 expression was also significantly prognostic of metastasis in a publically available LPS cohort. Finally, we demonstrate that a three gene signature comprised of PPP2R1B, RALA, and MMP14 can retrospectively stratify LPS patients into groups of low, moderate, or high risk for metastatic recurrence. To the best of our knowledge this is the first demonstration of a vital role for PPP2R1A and RALA in STS invasion and metastasis and these data demonstrate a novel role for RALA in the localization and activity of MMP14. In conclusion, we have identified the PPP2R1B-RALA-MMP14 axis as driver of STS metastasis with potential clinical value as both a prognostic marker and therapeutic target. Citation Format: Steven T. Sizemore, Fen Xia, Arnab Chakravarti. The RALA pathway drives invasion and metastasis of soft tissue sarcomas by regulating MMP14 localization and activity. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1634.

Recently, a genome-wide association study of gastric cancer (GC) reported the significant association of seven genetic variants (rs4072037 and rs4460629 on 1q22; rs753724, rs11187842, rs3765524, rs2274223, and rs3781264 on 10q23) with GC in a Chinese population. These findings were confirmed in a subsequent independent study. However, it remains unknown whether these loci are associated with an increased risk of colorectal cancer (CRC). This study was to test whether the seven single nucleotide polymorphisms (SNPs) associated with GC were also associated with CRC in a Chinese population. The seven SNPs were genotyped using MassARRAY system. Allelic, genotypic, and haplotypic associations of the SNPs with CRC were investigated using χ(2) tests and logistic regression analysis. The SNPs rs3765524 and rs2274223, located on 10q23, were found to have significant protective effects against CRC, with equal odds ratios per allele. The two SNPs located on 1q22 (rs4072037 and rs4460629) showed a weak association with CRC. No significant association was identified with CRC for the remaining three SNPs located on 10q23 (rs753724, rs11187842, and rs3781264). These results suggest that rs3765524 and rs2274223 on 10q23 are associated with a protective effect against CRC in a Chinese population.

Subcellular localization regulates BRCA1 function, and BRCA1 is exported to the cytoplasm following DNA damage in a p53-dependent manner. Because more than 50% of solid tumors harbor p53 mutations, it is possible that genetically wild-type (wt) BRCA1 is functionally abnormal through compromised nuclear-cytoplasmic shuttling in sporadic breast cancer patients with dysfunctional p53. In this study, we have investigated the mechanisms of p53-dependent BRCA1 subcellular distribution and DNA damage-induced nuclear export, as well as the impact on the resulting cytotoxic response to therapy in human breast cancer. We first show that p53 mediates BRCA1 nuclear export via protein–protein binding, rather than by modulation of its transcription. Furthermore, it is the C-terminal (BRCT) region of BRCA1 that is critical for its interaction with p53, and p53 may promote BRCA1 nuclear export by interrupting the association of BRCA1 with BARD1. In sporadic breast cancer specimens, dysfunctional p53 strongly correlates with nuclear retention of sequence-verified wt BRCA1. This p53-dependent BRCA1 shuttling determines cellular susceptibility to DNA damage as augmentation of cytosolic BRCA1 significantly enhances cancer cell susceptibility to ionizing radiation. Taken together, our data suggest that p53 dysfunction compromises nuclear export of wt BRCA1 as a mechanism to increase cellular resistance to DNA damage in sporadic breast cancer. We propose that targeting nuclear BRCA1 to the cytoplasm may offer a unique strategy to sensitize p53-deficient sporadic breast cancers to DNA damage–based therapy. Cancer Res; 71(16); 5546–57. ©2011 AACR.

Background: Cerebral radiation necrosis is a relatively common complication of radiation therapy for intracranial malignancies which can also rarely be encountered after radiation of extracranial lesions of the head and neck. We present the first reported case of cerebral radiation necrosis in a patient who underwent radiation therapy for a plasmacytoma of the skull. Case Description: A 68-year-old male with multiple myeloma presented with an enhancing right frontal mass, 8 years after receiving radiation therapy for a plasmacytoma of the left frontal skull. The patient underwent a diagnostic and therapeutic craniotomy for a presumed neoplastic lesion. The pathologic diagnosis made in this case was delayed radiation necrosis. The patient was followed for over a year during which this process continued to evolve before the ultimate resolution of his clinical symptoms and radiographic abnormality. Conclusion: This case highlights the importance of considering radiation necrosis in the differential diagnosis of any patient with an intracranial mass and a history of radiation for an extracranial head and neck malignancy, regardless of timing and laterality. This case also provides unique insights into the ongoing debate regarding the role of the aberrant immune response in the pathogenesis of delayed cerebral radiation necrosis.

SMAD7 has been demonstrated to antagonize TGF-β-mediated fibrosis, carcinogenesis, and inflammation. Two previous genome-wide association studies identified three single nucleotide polymorphisms (SNPs) (rs4939827, rs12953717 and rs4464148) in SMAD7 to be associated with colorectal cancer in a Western population. We conducted the first case–control study in a Han Chinese population to explore the associations between these three SNPs and colorectal, gastric, and lung cancers. Of the three SNPs, only rs12953717 was strongly associated with the three types of cancer, fitting the overdominant model. Compared with the CC/TT (CC combined with TT) genotype, the adjusted odds ratios for the CT genotype were 2.002 (95% CI, 1.250–3.207, P = 0.004), 1.678 (95% CI, 1.048–2.689, P = 0.031), 3.825 (95% CI, 2.310–6.335, P

Long-term neurological deficiencies resulting from hippocampal cytotoxicity induced by cranial irradiation (IR) present a challenge in the treatment of primary and metastatic brain cancers, especially in children. Previously, we showed that lithium protected hippocampal neurons from IR-induced apoptosis and improved neurocognitive function in treated mice. Here, we demonstrate accelerated repair of IR-induced chromosomal double-strand breaks (DSBs) in lithium-treated neurons. Lithium treatment not only increased IR-induced DNA-dependent protein kinase (DNA-PK) threonine 2609 foci, a surrogate marker for activated nonhomologous end-joining (NHEJ) repair, but also enhanced double-strand DNA end-rejoining activity in hippocampal neurons. The increased NHEJ repair coincided with reduced numbers of IR-induced gamma-H2AX foci, well-characterized in situ markers of DSBs. These findings were confirmed in vivo in irradiated mice. Consistent with a role of NHEJ repair in lithium-mediated neuroprotection, attenuation of IR-induced apoptosis of hippocampal neurons by lithium was dramatically abrogated when DNA-PK function was abolished genetically in SCID mice or inhibited biochemically by the DNA-PK inhibitor IC86621. Importantly, none of these findings were evident in glioma cancer cells. These results support our hypothesis that lithium protects hippocampal neurons by promoting the NHEJ repair-mediated DNA repair pathway and warrant future investigation of lithium-mediated neuroprotection during cranial IR, especially in the pediatric population.

A major goal of current cancer research is to understand the functional consequences of mutations in recombinational DNA repair genes. The introduction of artificial recombination substrates into living cells has evolved into a powerful tool to perform functional analysis of DNA double strand break (DSB) repair. Here, we review the principles and practice of current plasmid assays with regard to the two major DSB repair pathways, homologous recombination and nonhomologous end-joining. A spectrum of assay types is available to assess repair in a wide variety of cell lines. However, several technical challenges still need to be overcome. Understanding the alterations of DSB repair in cancers will ultimately provide a rational basis for drug design that may selectively sensitize tumor cells to ionizing radiation and chemotherapy, thereby achieving therapeutic gain.