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For patients with rectal cancer, the standard approach of chemotherapy, radiation therapy, and surgery (trimodality therapy) is associated with significant long-term toxicity and/or colostomy for most patients. Patient options focused on quality of life (QOL) have dramatically improved, but there remains limited guidance regarding comparative effectiveness. This systematic review and associated guidelines evaluate how various treatment strategies compare to each other in terms of oncologic outcomes and QOL. Cochrane and Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) methodology were used to search for prospective and retrospective trials and meta-analyses of adequate quality within the Ovid Medline database between January 1, 2012, and June 15, 2023. These studies informed the expert panel, which rated the appropriateness of various treatments in 6 clinical scenarios through a well-established consensus methodology (modified Delphi). The search process yielded 197 articles that advised voting. Increasing data have shown that nonoperative management (NOM) and primary surgery result in QOL benefits noted over trimodality therapy without detriment to oncologic outcomes. For patients with rectal cancer for whom total mesorectal excision would result in permanent colostomy or inadequate bowel continence, NOM was strongly recommended as usually appropriate. Restaging with tumor response assessment approximately 8 to 12 weeks after completion of radiation therapy/chemoradiation therapy was deemed a necessary component of NOM. The panel recommended active surveillance in the setting of a near-complete or complete response. In the setting of NOM, 54 to 56 Gy in 27 to 31 fractions concurrent with chemotherapy and followed by consolidation chemotherapy was recommended. The panel strongly recommends primary surgery as usually appropriate for a T3N0 high rectal tumor for which low anterior resection and adequate bowel function is possible, with adjuvant chemotherapy considered if N+. Recent data support NOM and primary surgery as important options that should be offered to eligible patients. Considering the complexity of multidisciplinary management, patients should be discussed in a multidisciplinary setting, and therapy should be tailored to individual patient goals/values., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Treatment of unresectable colorectal liver metastases (UCRLM) includes locoregional and systemic therapy. A comprehensive analysis capturing long-term outcomes of these treatment options has not been performed., Objective: A systematic review and meta-analysis was performed to calculate pooled outcomes of hepatic artery infusion with systemic chemotherapy (HAI-S), transarterial chemoembolization with systemic chemotherapy (TACE-S), transarterial radioembolization with systemic chemotherapy (TARE-S), doublet (FOLFOX, FOLFIRI), and triplet chemotherapy (FOLFOXIRI)., Methods: Outcomes included overall survival (OS), progression-free survival (PFS), rate of conversion to resection (CTR), and response rate (RR)., Results: A total of 32, 7, 9, and 14 publications were included in the HAI-S, TACE-S, and TARE-S chemotherapy arms. The 6/12/24/36-month OS estimates for HAI-S, TACE-S, TARE-S, FOLFOX, FOLFIRI, and FOLFOXIRI were 97%/80%/54%/35%, 100%/83%/40%/14%, 82%/61%/34%/21%, 96%/83%/53%/36%, and 96%/93%/72%/55%. Similarly, the 6/12/24/36-month PFS estimates were 74%/44%/19%/14%, 66%/20%/9%/3%, 57%/23%/10%/3%, 69%/30%/12%/7%, and 88%/55%/18%/11%. The corresponding CTR and RR rates were 31, 20%, unmeasurable (TARE-S), 35, 53; and 49, 45, 45, 50, 80%, respectively. The majority of chemotherapy studies included first-line therapy and liver-only metastases, whereas most HAI-S studies were pretreated. On subgroup analysis in first-line setting with liver-only metastases, the HAI-S arm had comparable outcomes to FOLFOXIRI and outperformed doublet chemotherapy regimens. Although triplet chemotherapy appeared to outperform other arms, high toxicity and inclusion of potentially resectable patients must be considered while interpreting results., Conclusions: HAI-S and multiagent chemotherapy are effective therapies for UCRLM. To make definitive conclusions, a randomized trial with comparable patient characteristics and line of therapy will be required. The upcoming EA2222 PUMP trial may help to address this question., (© 2024. The Author(s).)

(1) Background: Local therapies offer a potentially curative approach for patients with oligometastatic colorectal cancer (CRC). An evidence-based consensus recommendation for systemic therapy following definitive locoregional therapy is lacking. Tumor-informed circulating tumor DNA (ctDNA) might provide information to help guide management in this setting. (2) Methods: A multi-institutional retrospective study was conducted, including patients with CRC that underwent curative-intent locoregional therapy to an isolated site of metastatic disease, followed by tumor-informed ctDNA assessment. The Kaplan-Meier method and log-rank tests were used to compare disease-free survival based on ctDNA results. ctDNA test performance was compared to carcinoembryonic antigen (CEA) test results using McNemar's test. (3) Results: Our study cohort consisted of 87 patients treated with locoregional interventions who underwent ctDNA testing. The initial ctDNA test post-intervention was positive in 28 patients and negative in 59 patients. The median follow-up time was 14.0 months. Detectable ctDNA post-intervention was significantly associated with early disease recurrence, with a median disease-free survival (DFS) of 6.63 months compared to 21.30 months in ctDNA-negative patients ( p < 0.001). ctDNA detected a numerically higher proportion of recurrences than CEA ( p < 0.097). Post-intervention systemic therapy was not associated with improved DFS ( p = 0.745). (4) Conclusions: ctDNA results are prognostically important in oligometastatic CRC, and further prospective studies are urgently needed to define its role in guiding clinical decisions.

Background: Preclinical studies have demonstrated that VT1021, a first-in-class therapeutic agent, inhibits tumor growth via stimulation of thrombospondin-1 (TSP-1) and reprograms the tumor microenvironment. We recently reported data from the dose escalation part of a phase I study of VT1021 in solid tumors. Here, we report findings from the dose expansion phase of the same study., Methods: We analyzed the safety and tolerability, clinical response, and biomarker profile of VT1021 in the expansion portion of the phase I study (NCT03364400). Safety/tolerability is determined by adverse events related to the treatment. Clinical response is determined by RECIST v1.1 and iRECIST. Biomarkers are measured by multiplexed ion beam imaging and enzyme-linked immunoassay (ELISA)., Results: First, we report the safety and tolerability data as the primary outcome of this study. Adverse events (AE) suspected to be related to the study treatment (RTEAEs) are mostly grade 1-2. There are no grade 4 or 5 adverse events. VT1021 is safe and well tolerated in patients with solid tumors in this study. We report clinical responses as a secondary efficacy outcome. VT1021 demonstrates promising single-agent clinical activity in recurrent GBM (rGBM) in this study. Among 22 patients with rGBM, the overall disease control rate (DCR) is 45% (95% confidence interval, 0.24-0.67). Finally, we report the exploratory outcomes of this study. We show the clinical confirmation of TSP-1 induction and TME remodeling by VT1021. Our biomarker analysis identifies several plasmatic cytokines as potential biomarkers for future clinical studies., Conclusions: VT1021 is safe and well-tolerated in patients with solid tumors in a phase I expansion study. VT1021 has advanced to a phase II/III clinical study in glioblastoma (NCT03970447)., (© 2024. The Author(s).)

Introduction: We compared long-term survival of patients with localized biliary tract cancers (BTCs) treated with either surgical resection or multiagent chemotherapy., Methods: Patients with localized BTC [gallbladder adenocarcinoma, extrahepatic cholangiocarcinoma, intrahepatic cholangiocarcinoma] were identified within the National Cancer Database (2010-2017). Piecewise-constant hazard modeling was used to estimate hazard ratios (HRs) at prespecified intervals: 0-30 d, 31-60 d, 61-90 d, and >90 d post-treatment., Results: A total of 5988 patients with localized BTC were identified: 2697 (45.0%) received multiagent chemotherapy and 3291 (55.0%) underwent surgical resection. Patients with gallbladder adenocarcinoma or extrahepatic cholangiocarcinoma who were treated with surgical resection had an associated decline in overall survival (OS) as compared to those treated with multiagent chemotherapy within 0-30 d of treatment initiation (gallbladder adenocarcinoma [adjusted HR = 3.94, 95% confidence interval [CI]: 1.77-8.80]; extrahepatic cholangiocarcinoma [adjusted HR = 4.88, 95% CI: 2.76-8.61]). However, there was an associated improvement in OS for patients treated with surgical resection after 90 d from treatment initiation (gallbladder adenocarcinoma [adjusted HR = 0.36, 95% CI: 0.28-0.46]; extrahepatic cholangiocarcinoma [adjusted HR = 0.27, 95% CI: 0.24-0.32]). Among patients with intrahepatic cholangiocarcinoma, those who underwent surgical resection had an associated improvement in OS at 31-60 d (adjusted HR = 0.63, 95% CI: 0.40-0.99) and a further associated increase in OS at 61-90 d (adjusted HR = 0.34, 95% CI: 0.21-0.54) and after 90 d (HR = 0.23, 95% CI: 0.21-0.27) of treatment initiation., Conclusions: For patients with localized BTC, surgical resection alone is associated with improved long-term survival outcomes compared to multiagent chemotherapy alone., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Racial/ethnic disparities in metastatic colorectal cancer (mCRC) survival are well documented as is the impact that tumor mutation of KRAS and BRAF has on prognosis. It has been suggested that frequency differences of KRAS- and BRAF-mutated tumors may partially explain this disparity. Demographic differences in mutation frequency are not well established nor whether mutation and microsatellite instability (MSI) differentially impact survival among groups., Methods: Using data for 11,117 patients diagnosed with de-novo mCRC from an electronic health record-derived database we estimated adjusted odds ratios (aOR) to characterize the association between demographics and MSI and KRAS/NRAS/BRAF-mutation status. Stratified Cox models were used to identify differences in overall survival (OS), adjusting for treatment and demographics., Results: Being female, compared to male, (aOR KRAS :1.33 (1.23-1.44); aOR BRAF :1.84 (1.56-2.16)), and non-Hispanic Black race (NHB), compared to non-Hispanic White (NHW) (aOR KRAS :1.62 (1.42-1.85); aOR BRAF : 0.55 (0.38-0.77)) were associated with KRAS- or BRAF-mutant tumors. MSI prevalence was similar across race/ethnicity but higher in women. BRAF-mutant tumors were associated with poorer prognosis overall, especially among non-white patients. Among patients who had KRAS/NRAS/BRAF-WT tumors we observed no difference in OS by race or MSI. Among patients with KRAS-mutant tumors, Hispanic patients had more favorable prognosis adjusted hazards ratio (aHR) = 0.76 (0.65-0.89)) than their NHW counterparts. Among those with BRAF-mutant tumors, NHB patients had poorer prognosis than NHW patients (aHR:1.78 (1.08-2.93))., Conclusion: MSI and frequency of KRAS and BRAF mutations differed by demographics. Racial/ethnic disparities in OS differed by mutation. Future studies should explore biological and/or social determinants underlying these differences., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Neutrophil extracellular traps (NETs), a web-like structure of cytosolic and granule proteins assembled on decondensed chromatin, kill pathogens and cause tissue damage in diseases. Whether NETs can kill cancer cells is unexplored. Here, we report that a combination of glutaminase inhibitor CB-839 and 5-FU inhibited the growth of PIK3CA-mutant colorectal cancers (CRCs) in xenograft, syngeneic, and genetically engineered mouse models in part through NETs. Disruption of NETs by either DNase I treatment or depletion of neutrophils in CRCs attenuated the efficacy of the drug combination. Moreover, NETs were present in tumor biopsies from patients treated with the drug combination in a phase II clinical trial. Increased NET levels in tumors were associated with longer progression-free survival. Mechanistically, the drug combination induced the expression of IL-8 preferentially in PIK3CA-mutant CRCs to attract neutrophils into the tumors. Further, the drug combination increased the levels of ROS in neutrophils, thereby inducing NETs. Cathepsin G (CTSG), a serine protease localized in NETs, entered CRC cells through the RAGE cell surface protein. The internalized CTSG cleaved 14-3-3 proteins, released BAX, and triggered apoptosis in CRC cells. Thus, our studies illuminate a previously unrecognized mechanism by which chemotherapy-induced NETs kill cancer cells.

Background: We examined disparities in guideline-compliant care at minority-serving hospitals (MSH) versus non-MSH among patients with localized or metastatic pancreatic adenocarcinoma (PDAC)., Methods: Patients with PDAC were identified within the National Cancer Database (2004-2018). Guideline-compliant care was defined as surgery + chemotherapy ± radiation therapy for localized and chemotherapy for metastatic disease. Facilities in the top decile of minority patients treated were considered MSH., Results: A total of 190,950 patients were identified and most (59.6%) had metastatic disease. Overall, 6.4% of patients with localized and 8.2% of patients with metastatic disease were treated at MSH. Patients treated at MSH were less likely to receive guideline-compliant care (localized: OR = 0.78, 95% CI: 0.67-0.91; metastatic: OR = 0.77, 95% CI: 0.67-0.88). Minority patients were less likely to receive guideline-compliant care at non-MSH (localized: OR = 0.71, 95% CI: 0.67-0.75; metastatic: OR = 0.85, 95% CI: 0.82-0.89) or MSH (localized: OR = 0.85, 95% CI: 0.74-0.98; metastatic: OR = 0.91, 95% CI: 0.82-0.99). Patients treated at non-MSH or MSH who received guideline-compliant care were more likely to have higher OS regardless of stage or race., Conclusions: MSH patients were less likely to receive guideline-compliant care and minority patients were less likely to receive guideline-compliant care regardless of MSH status. Guideline-compliant care was associated with improved OS., (Copyright © 2023 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Background: We examined differences in surgical intervention at minority-serving hospitals versus non-minority-serving hospitals among patients with early-stage hepatocellular carcinoma. We also investigated associations between surgical management and overall survival, stratified by minority-serving hospital status., Methods: Patients with early-stage hepatocellular carcinoma, defined as cT1, were identified within the National Cancer Database (2004-2018). The primary outcome was surgical intervention (resection, ablation, or transplantation). The proportion of minority (non-Hispanic Black or Hispanic) patients treated at each facility was determined, and hospitals in the top decile were considered minority-serving hospitals., Results: A total of 46,703 patients with early-stage hepatocellular carcinoma were identified, of whom 4,214 (9.0%) were treated at minority-serving hospitals. Patients treated at minority-serving hospitals were less likely to undergo surgical intervention than patients treated at non-minority-serving hospitals (odds ratio = 0.87, 95% confidence interval: 0.81-0.94). Minority patients treated at non-minority-serving hospitals were less likely to undergo surgical intervention than White patients (odds ratio = 0.86, 95% confidence interval: 0.82-0.90) and had a further associated decrease in the likelihood of surgical intervention when treated at minority-serving hospitals (odds ratio = 0.81, 95% confidence interval: 0.69-0.94). Regardless of minority-serving hospital status, surgery was associated with improved overall survival. There were no clinically meaningful differences in overall survival between White and minority patients who underwent surgery either at minority-serving hospitals or non-minority-serving hospitals., Conclusions: Patients with early-stage hepatocellular carcinoma had an associated decrease in the likelihood of surgical intervention when treated at minority-serving hospitals. Minority patients treated at minority-serving hospitals had an associated decrease in the likelihood of surgery, but to a lesser extent when treated at non-minority-serving hospitals. Surgery was associated with improved overall survival regardless of minority or minority-serving hospital status., (Copyright © 2023 Elsevier Inc. All rights reserved.)

The liver is a common site of cancer metastases. Systemic therapy is widely accepted as the standard treatment for liver metastases (LM), although select patients with liver oligometastases may be candidates for potentially curative liver resection. Recent data support the role of nonsurgical local therapies such as ablation, external beam radiotherapy, embolization, and hepatic artery infusion therapy for management of LM. Additionally, for patients with advanced, symptomatic LM, local therapies may provide palliative benefit. The American Radium Society gastrointestinal expert panel, including members representing radiation oncology, interventional radiology, surgical oncology, and medical oncology, performed a systemic review and developed Appropriate Use Criteria for the use of nonsurgical local therapies for LM. Preferred Reporting Items for Systematic reviews and Meta-Analyses methodology was used. These studies were used to inform the expert panel, which then rated the appropriateness of various treatments in seven representative clinical scenarios through a well-established consensus methodology (modified Delphi). A summary of recommendations is outlined to guide practitioners on the use of nonsurgical local therapies for patients with LM., (© 2023 American Cancer Society.)

Objective: To define the optimal threshold of perioperative chemotherapy completion and relative dose intensity (RDI) for patients with resected pancreatic ductal adenocarcinoma (PDAC)., Background: Many patients who undergo pancreatectomy for PDAC fail to initiate or complete recommended perioperative chemotherapy. The association between the amount of perioperative chemotherapy received and overall survival (OS) is not well-defined., Methods: Single-institution analysis of 225 patients who underwent pancreatectomy for stage I/II PDAC (2010-2021). Associations between OS, chemotherapy cycles completed, and RDI were analyzed., Results: Regardless of treatment sequence, completion of ≥67% of recommended cycles was associated with improved OS compared with no chemotherapy [median OS: 34.5 vs 18.1 months; hazard ratio (HR): 0.43; 95% CI: 0.25-0.74] and <67% of cycles (median OS: 17.9 months; HR: 0.39; 95% CI: 0.24-0.64). A near-linear relationship existed between cycles completed and the RDI received (β = 0.82). A median RDI of 56% corresponded to the completion of 67% of cycles. Receipt of ≥56% RDI was associated with improved OS compared with no chemotherapy (median OS: 35.5 vs 18.1 months; HR: 0.44; 95% CI: 0.23-0.84) and <56% RDI (median OS: 27.2 months; HR: 0.44; 95% CI: 0.20-0.96). Neoadjuvant chemotherapy is associated with increased odds of receiving ≥67% of recommended cycles (odds ratio: 2.94; 95% CI: 1.45-6.26) and ≥56% RDI (odds ratio: 4.47; 95% CI: 1.72-12.50)., Conclusions: Patients with PDAC who received ≥67% of recommended chemotherapy cycles or ≥56% cumulative RDI had improved OS. Neoadjuvant therapy was associated with increased odds of receiving ≥67% of cycles and ≥56% cumulative RDI and should be considered in all patients with resectable PDAC., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Disparities in cancer care delivery remain a pressing health-care crisis within the United States (US). The use of immune checkpoint inhibitors (ICIs) and their management may be a disparity generator that impacts survival. This retrospective study assessed disparities in a cohort of patients with a variety of solid tumors treated with ICIs within a single health-care organization focusing on the impact of race, socioeconomic status (SES) and site of care delivery on survival and the development of severe immune-related adverse events (irAEs)., Patients and Methods: Manual chart review was performed on all patients with solid tumors treated with ICIs within a health-care organization from 2012 to 2018. Care delivery was dichotomized as DOP (disease-oriented provider at academic center) and COP (community oncology provider). Primary and secondary outcomes were overall survival (OS) and rates of grade 3-4 irAEs, respectively. Relationships with covariates of interest, including race, socioeconomic status and type of care delivery, were assessed among both outcomes., Results: A total of 1070 eligible patients were identified. Of those, 11.4% were of Black race, 59.7% had either non-small cell lung cancer (NSCLC) or melanoma and 82.8% had stage IV disease. Patients of Black race and lower SES were more likely to be treated by DOPs (p<0.0001). A superior OS was associated with care delivered by DOPs when compared to COPs (HR 0.68; 95% CI 0.56-0.84; p=0.0002), which was durable after accounting for race, SES, histopathologic diagnosis and disease stage. Melanoma patients experienced higher rates of severe irAEs (HR 2.37; 95% CI 1.42-3.97; p=0.001). Race, SES and site of care delivery were not related to rates of severe irAEs., Conclusion: In a large health-care organization, patients treated with checkpoint inhibitors by DOPs benefited from a significant OS advantage that was durable after controlling for racial and socioeconomic factors, providing evidence that disease-oriented care has the potential to mitigate racial and socioeconomic disparities., Competing Interests: Christopher Hoimes reports grants, personal fees from Merck, BMS, Genentech, Seagen, Astellas, and Eisai, during the conduct of the study. Debora S Bruno reports personal fees from Bristol Myers Squibb, Novartis, Eli Lilly, Amgen, Mirati Therapeutics, AstraZeneca, TEMPUS, Daiichi-Sankyo, and grants from AstraZeneca, outside the submitted work. Afshin Dowlati reports being on the advisory board for Ipsen, BMS, Merck, Astra Zeneca, and Seattle Genetics, during the conduct of the study. The authors report no other conflicts of interest in this work., (© 2023 Mirsky et al.)

Treatment with radiolabelled somatostatin analogs, a form of peptide receptor radionuclide therapy (PRRT), has changed the management of patients with advanced gastroenteropancreatic neuroendocrine tumors (GEP-NETs). There is a subgroup of patients who have suboptimal benefit and rapidly progress on PRRT, indicating that accurate prognostic and predictive markers are urgently needed. Currently, most of the literature concentrate on the prognostic impact of the dual positron emission tomography (PET) scan with very few information regarding the predictive value. We report a case series and review the literature to summarizes the predictive value of combined somatostatin receptor (SSTR) and fluorodeoxyglucose (FDG) PET in metastatic GEP-NETs. We conducted a review of the literature for data published from 2010 to 2021 in MEDLINE, Embase, the National Institutes of Health trial registry, Cochrane CENTRAL, and published proceedings from major gastrointestinal and neuroendocrine cancer meetings. Our main criteria included all published prospective and retrospective data in which the predictive value of dual PET scans using SSTR and FDG was correlated with PRRT response in patients with metastatic GEP-NETs. We summarized clinical outcomes including progression-free survival (PFS), overall survival (OS), and post-therapy complications associated with PRRT according to FDG avidity. We excluded studies that did not include FDG PET scan, GEP patients, studies with no clear predictive value of the FDG PET scan, and studies that did not report a direct correlation between FDG avidity and primary outcome. Additionally, we summarized our institutional experience in eight patients who progressed during or within the first year of PRRT treatment. Our search identified 1306 articles; most of them showed only the prognostic value of Integrated SSTR/FDG PET imaging biomarker in GEP-NETs. Only three studies (n=75 patients) met our inclusion criteria and retrospectively investigated the predictive value of dual SSTR and FDG imaging in subjects being considered for PRRT. The results confirmed that FDG avidity correlates with advanced NET grades. Lesions that are both SSTR and FDG avid had early disease progression. In one study, at multivariate analysis, FDG PET results were independently predictive of lower PFS for PRRT. In our case series, there were eight patients with metastatic well-differentiated GEP-NETs (grades 2 and 3) who progressed within one year of PRRT. Seven of them had positive FDG PET scan at the time of progression. In conclusion, Dual SSTR/FDG PET imaging has a potential predictive impact for PRRT in GEP-NETs. It permits the capturing of the disease complexity and aggressiveness, which correlates with PRRT response. Therefore, prospective future trials should validate the predictive value of dual SSTRs/FDG PET for better PRRT stratification., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://jgo.amegroups.com/article/view/10.21037/jgo-22-1011/coif). The authors have no conflicts of interest to declare., (2023 Journal of Gastrointestinal Oncology. All rights reserved.)

Background: We described trends and disparities in utilization of systemic chemotherapy in metastatic hepato-pancreato-biliary (HPB) cancers., Methods: We queried the National Cancer Database for metastatic HPB cancers [hepatocellular carcinoma (HCC), biliary tract cancers (BTC), pancreatic adenocarcinoma (PDAC)]. We used multivariable analysis to examine the factors associated with utilization of systemic chemotherapy. We utilized marginal structural logistic models to estimate the effect of health insurance, facility type, or facility volume on utilization of systemic chemotherapy., Results: We identified 162,283 patients with metastatic HPB cancers: 23,923 (14.7%) had HCC, 26,766 (16.5%) had BTC, and 111,594 (68.8%) had PDAC. A total of 37.2% patients with HCC, 55.6% with BTC, and 56.4% with PDAC received chemotherapy. Age ≥70 years and Charlson-Deyo score ≥2 were associated with lower likelihood of receiving chemotherapy across all cancers. Patients with private health insurance had higher receipt of chemotherapy. Receiving treatment at academic facilities had no effect on the receipt of chemotherapy. Treatment of patients with HCC or PDAC at high-volume facilities resulted in higher receipt of chemotherapy., Conclusion: A significant proportion of patients with metastatic HPB cancers do not receive systemic chemotherapy. Several disparities in administration of chemotherapy for metastatic HPB cancers exist., (Copyright © 2022 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Background: Surgical volume-outcome relationships have been described for a variety of procedures. There is scant literature on total institutional volume and outcomes in patients who are nonoperatively managed. We examined the average treatment effect of total hepatopancreatobiliary malignancy case volume on survival outcomes of patients with nonresected hepatobiliary malignancies., Methods: We identified patients with hepatopancreatobiliary malignancies [pancreatic adenocarcinoma, pancreatic neuroendocrine neoplasms, hepatocellular carcinoma, biliary tract cancers] within the National Cancer Database (2004-2018). We determined percentile thresholds based on the total annual hepatopancreatobiliary malignancy case volume. We then identified nonoperatively managed patients with hepatocellular carcinoma or biliary tract cancers. We used inverse probability-weighted Cox regression to estimate the effect of facility volume on overall survival., Results: We identified 710,988 patients with hepatopancreatobiliary malignancies. Total annual hepatopancreatobiliary malignancy case volume of 32, 71, and 177 cases/year corresponded to the 25th, 50th, and 75th percentiles. A total of 96,420 with hepatocellular carcinoma and 52,627 patients with biliary tract cancers were managed nonoperatively. In patients with hepatocellular carcinoma or biliary tract cancer, treatment at ≥25th, ≥50th, and ≥75th percentile facilities was associated with improved median, 1-, 2-, and 3-year overall survival compared with treatment at lower-percentile facilities. On inverse probability-weighted Cox analysis, treatment at higher-percentile facilities resulted in a lower hazard of death. Consistent findings were observed in patients with early or intermediate/advanced hepatocellular carcinoma or metastatic biliary tract cancers., Conclusion: Patients with nonoperatively managed hepatocellular carcinoma or biliary tract cancer who receive treatment at higher-volume facilities have improved survival outcomes. These data suggest regionalization of care for patients with hepatocellular carcinoma or biliary tract cancer to high-volume centers may improve survival., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Importance: Professional society guidelines recommend treating patients with metastatic colorectal cancer with targeted therapies, including epithelial growth factor receptor (EGFR) inhibitors and vascular endothelial growth factor (VEGF) inhibitors, depending on the presence or absence of certain mutations. Since most studies of first-line targeted therapies have been limited by sample size, there is a need for larger studies using data from routine clinical care., Objectives: To identify factors associated with receipt of first-line targeted therapies among patients with metastatic colorectal cancer for whom RAS or BRAF mutation data in the tumor were available and investigate whether targeted therapy is associated with survival., Design, Setting, and Participants: This cohort study used deidentified data from an electronic health record-derived database to include patients from 800 sites of patient care across the US who were diagnosed with de novo metastatic colorectal cancer between January 1, 2013, and March 31, 2020 (n = 9134)., Main Outcomes and Measures: Receipt of first-line targeted therapy, categorized as ever having received EGFR inhibitors, VEGF inhibitors, or neither. The secondary outcome was overall survival., Results: The study population included 9134 patients. The median age at diagnosis was 62 years (IQR, 53-71 years), 5019 (54.9%) were male, and 5692 (62.3%) were White. The median follow-up period was 15 months. Overall, 713 patients (7.8%) received EGFR inhibitors and 5081 patients (55.6%) received VEGF inhibitors as part of their first-line treatment. Among patients with RAS wild-type (RAS-WT) tumors, 625 patients (15.5%) received EGFR inhibitors and 2053 patients (50.9%) received VEGF inhibitors. In patients with RAS mutant (RAS-Mut) tumors, 50 patients (1.1%) received EGFR inhibitors and 2682 patients (59.7%) received VEGF inhibitors; among those with BRAF-mutant (BRAF-Mut) tumors, 38 patients (6.3%) received EGFR inhibitors and 346 patients (57.2%) received VEGF inhibitors. More than one-third of the patients (36.6%) received neither EGFR inhibitors nor VEGF inhibitors. Compared with patients younger than age 40 years, those aged 80 years or older had significantly lower odds to receive targeted therapies (EGFR or VEGF inhibitors in patients with RAS-WT tumors: adjusted odds ratio [aOR], 0.53; 95% CI, 0.36-0.79; and VEGF inhibitors in patients with RAS-Mut tumors: aOR, 0.62; 95% CI, 0.42-0.90). Improved survival was associated with EGFR inhibitor therapy in patients with RAS-WT tumors (adjusted hazard ratio [aHR], 0.85; 95% CI, 0.74-0.98). Unlike in clinical trials, however, no survival benefit was noted with use of VEGF inhibitors among patients with RAS-WT (aHR, 1.00; 95% CI, 0.91-1.11) or RAS-Mut (aHR, 1.01; 95% CI, 0.93-1.10) tumors., Conclusions and Relevance: The findings of this study showed mixed results on survival benefits associated with targeted therapy. In addition, given that some of the results differed from those of randomized clinical trials, this study highlights the importance of using data originating from routine clinical care.

Background: Standard clinical practice and national guidelines dictate somatic testing of metastatic colorectal cancer (mCRC) tumors to guide appropriate therapy; however, previous studies suggest that not all patients are tested. The objective of this study was to investigate potential differences in testing for mCRC by demographic and clinical factors., Methods: We performed a retrospective review of de-identified patient data derived from electronic health records (EHRs) of 25,469 patients diagnosed with mCRC between the years 2013 and 2020. Our outcome was a receipt of the following tests: (a) biomarker testing (BRAF, KRAS, NRAS, MMR/MSI) and (b) next-generation sequencing (NGS). We interrogated our data using the machine-learning algorithm Classification and Regression Tree (CART), a unique approach to identifying combinations of, rather than individual demographic and clinical characteristics associated with receipt of testing., Results: A total of 25,469 patients were identified with mCRC. Of these, 21,133 (83%) received either biomarker testing only (n = 12,485) or any testing (biomarker + NGS) (n = 8648). The proportion of patients who received any testing increased over calendar time for all age, race, and sex categories. Receipt of any testing was highest (90%) among younger and patients with better performance status, and there was no difference in receipt of any testing by race. The highest percentage of NGS testing was among those with better performance status, <70 years old, commercial or other governmental program payers, and low comorbidity burden; however, those who were Black or Hispanic had a lower prevalence of NGS testing than those who were White., Conclusions and Relevance: Considerable variations exist in somatic biomarker testing across subgroups of the population. Identification of genomic alterations can aid in determining targeted treatment and improving clinical outcomes; therefore, equitable use of these testing strategies, particularly NGS, is necessary., (© 2022 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Appendiceal neuroendocrine neoplasms (ANENs) usually present as incidental findings at the time of appendectomy for acute appendicitis. They are rare, accounting for only 0.5-1% of intestinal neoplasms; they are found in 0.3-0.9% of all appendectomy specimens. They are usually sporadic tumors. There are several histological types including well-differentiated neuroendocrine tumors (NETs), poorly differentiated neuroendocrine carcinomas (NECs), and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs). Histologic differentiation and the grade of well-differentiated NETs correlate with clinical behavior and prognosis. Management varies based on differentiation, aggressiveness, and metastatic potential. There is debate about the optimal surgical management for localized appendiceal NETs that are impacted by many factors including the tumor size, the extent of mesoappendiceal spread, lymphovascular invasion and perineural involvement. In addition, the data to guide therapy in metastatic disease are limited due to the paucity of these tumors. Here, we review the current advances in the management of ANENs within the context of a multidisciplinary approach to these tumors.

Background: To examine the average treatment effect of hepato-pancreato-biliary (HPB) cancer volume on survival outcomes of patients with non-resected pancreatic adenocarcinoma (PDAC)., Methods: We queried the National Cancer Database (2004-2018) for patients with HPB malignancies (PDAC, pancreatic neuroendocrine neoplasms, hepatocellular carcinoma, biliary tract cancers). We determined the 25th, 50th, and 75th percentiles based on the total annual HPB volume. We then identified patients with non-resected PDAC. We utilized inverse probability (IP)-weighted Cox regression to estimate the effect of facility volume on overall survival (OS)., Results: We identified 710,988 patients with HPB malignancies. The 25th, 50th, and 75th percentiles of total annual HPB volume were 32, 71, and 177 cases/year, respectively. We included a total of 196,150 patients with non-resected PDAC. Patients treated at ≥25th, ≥50th, and ≥75th percentile facilities had improved median OS compared to those treated at facilities below these thresholds (5.8 vs. 4.2months, 6.5 vs. 4.5months, 7.5 vs. 4.8months, respectively; p < 0.001 for all). Treatment at facilities ≥25th, ≥50th, and ≥75th percentile resulted in lower hazards of death than treatment at lower-percentile facilities (HR: 0.87, 95% CI: 0.84-0.90; HR: 0.87, 95% CI: 0.83-0.91; HR: 0.85, 95% CI: 0.79-0.91, respectively)., Conclusion: Our data suggest that consolidation of care of patients with PDAC to high-volume centers may be beneficial even in the nonoperative setting., (Copyright © 2022. Published by Elsevier Ltd.)

Background: We describe factors associated with trial enrollment for patients with hepato-pancreato-biliary (HPB) malignancies. We analyzed the association and effect of trial enrollment on overall survival (OS)., Methods: The National Cancer Database (2004-2017) was queried for common HPB malignancies (pancreatic adenocarcinoma [PDAC] & neuroendocrine tumors, hepatocellular carcinoma [HCC], biliary tract cancers [BTC]). Multivariable logistic regression was used to identify factors associated with trial enrollment. OS was analyzed by multivariable Cox regression. Inverse-probability-weighted Cox regression was utilized to determine the effect of trial enrollment on OS., Results: A total of 1573 (0.3%) of 511,639 patients were enrolled in trials; pancreatic malignancy: 1214 (0.4%); HCC: 217 (0.14%); BTC: 106 (0.15%). HCC and BTC were associated with lower likelihood of enrollment compared with pancreatic malignancy. Black and Hispanic patients were less likely to be enrolled compared to White patients. Treatment at academic facilities and metastatic disease were associated with higher likelihood of enrollment. Enrollment was associated with higher OS for PDAC, metastatic HCC, and metastatic BTC. Trial enrollment exhibited an OS advantage for PDAC and metastatic HCC., Conclusion: Nationally, fewer than 1% of patients with HPB malignancies were enrolled in clinical trials. There are racial, sociodemographic, and facility-based disparities in trial enrollment., (Copyright © 2022 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Gut microbiome balance plays a key role in human health and maintains gut barrier integrity. Dysbiosis, referring to impaired gut microbiome, is linked to a variety of diseases, including cancers, through modulation of the inflammatory process. Most studies concentrated on adenocarcinoma of different sites with very limited information on gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs). In this study, we have analyzed the gut microbiome (both fungal and bacterial communities) in patients with metastatic GEP-NENs. Fecal samples were collected and compared with matched healthy control samples using logistic regression distances utilizing R package MatchIt (version 4.2.0, Daniel E. Ho, Stanford, CA, USA). We examined differences in microbiome profiles between GEP-NENs and control samples using small subunit (SSU) rRNA (16S), ITS1, ITS4 genomic regions for their ability to accurately characterize bacterial and fungal communities. We correlated the results with different behavioral and dietary habits, and tumor features including differentiation, grade, primary site, and therapeutic response. All tests are two-sided and p -values ≤ 0.05 were considered statistically significant. Gut samples of 34 patients (12 males, 22 females, median age 64 years) with metastatic GEP-NENs (22 small bowel, 10 pancreatic, 1 gall bladder, and 1 unknown primary) were analyzed. Twenty-nine patients had well differentiated GEP-neuroendocrine tumors (GEP-NETs), (G1 = 14, G2 = 12, G3 = 3) and five patients had poorly differentiated GEP-neuroendocrine carcinomas (GEP-NECs). Patients with GEP-NENs had significantly decreased bacterial species and increased fungi (notably Candida species, Ascomycota, and species belonging to saccharomycetes) compared to controls. Patients with GEP-NECs had significantly enriched populations of specific bacteria and fungi (such as Enterobacter hormaechei , Bacteroides fragilis and Trichosporon asahii ) compared to those with GEP-NETs ( p = 0.048, 0.0022 and 0.034, respectively). In addition, higher grade GEP-NETs were associated with significantly higher Bacteroides fragilis ( p = 0.022), and Eggerthella lenta ( p = 0.00018) species compared to lower grade tumors. There were substantial differences associated with dietary habits and therapeutic responses. This is the first study to analyze the role of the microbiome environment in patients with GEP-NENs. There were significant differences between GEP-NETs and GEP-NECs, supporting the role of the gut microbiome in the pathogenesis of these two distinct entities.

Background: Most patients with pancreatic adenocarcinoma (PDAC) do not undergo surgical resection. The role of radiotherapy (RT) in non-operatively managed localized pancreatic adenocarcinoma is unclear., Methods: The National Cancer Database (2010-2016) was queried for patients with clinical stage II-III PDAC treated with multiagent systemic chemotherapy (CT) +/- RT but not surgery. Factors associated with the receipt of RT and overall survival were compared after adjusting for patient demographics and clinical characteristics., Results: A total of 14,921 patients were included, of whom 9279 received CT and 5382 received CT + RT. Patients treated with CT + RT were more likely to be younger (65vs66yrs), treated at non-academic facilities (48.8%vs46.7%), have private insurance (40.3%vs36.5%), and have clinical T4 tumors (53.6%vs48.7%). Most patients who were treated with RT received external beam radiotherapy (89.3%), and the median dose was 5,000 cGy. Median time to start of RT was 129 days. CT + RT was associated with longer overall survival (15.9vs11.8mos,p < 0.001), and remained associated with survival on multivariable analysis (HR 0.74, 95%CI 0.70-0.78). On a 4-month conditional survival analysis, combined CT + RT remained associated with improved survival compared to CT alone (16.0vs13.1mos,p < 0.001)., Conclusions: In patients with non-operatively managed localized pancreatic adenocarcinoma, combined radiotherapy and multiagent systemic chemotherapy is associated with improved overall survival compared to chemotherapy alone., (Copyright © 2021 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.)

Objectives: Resection of locoregional pancreatic neuroendocrine neoplasms (PanNENs) is typically recommended, but there is a paucity of data on the management of elderly patients., Methods: The National Cancer Database (2004-2016) was queried for patients 80 years or older with localized PanNENs. Patients were grouped as nonoperative or operative management. Postoperative outcomes and survival were compared., Results: In total, 591 patients were included: 202 underwent resection, and 389 did not. Increasing age and pancreatic head tumors were associated with lower likelihood of resection. The overall 90-day mortality rate was 6.4%, which was higher for pancreatoduodenectomy than distal pancreatectomy (13.6% vs 5.1%, respectively). Operatively managed patients had longer median survival (80.8 vs 45.0 months, P < 0.001), and this association was independent of tumor location. On multivariable Cox regression, resection remained associated with longer survival (hazard ratio, 0.69; 95% confidence interval, 0.50-0.95). Among operatively managed patients, age and tumor location were not associated with survival; however, greater comorbidity and high-risk tumor-specific features were associated with worse survival., Conclusions: Resection of nonfunctional PanNENs in elderly patients is associated with improved survival compared with nonoperative management. Resection could be considered in appropriate operative candidates, regardless of tumor location, but the perioperative mortality rate must be considered., Competing Interests: The authors declare no conflict of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Neoadjuvant chemotherapy (CT) is being utilized more frequently in patients diagnosed with localized pancreatic cancer. The role of additional neoadjuvant radiotherapy (RT) remains undefined. We explored outcomes associated with neoadjuvant RT in the modern era., Methods: The National Cancer Database (2010-2017) was queried for patients with clinical stage II-III pancreatic adenocarcinoma who received neoadjuvant multiagent systemic CT +/- RT. Demographics, pathologic outcomes, postoperative outcomes, and overall survival were compared., Results: A total of 5245 patients were included, of whom 3123 received CT and 1941 received CT + RT. Use of RT decreased over the 8-year study period. On multivariable analysis, treatment at academic facilities (odds ratio (OR) = 1.52, P < .001) and clinical T4 tumors (OR = 1.68, P < .001) were independently associated with receipt of RT. Patients treated with CT + RT had a higher frequency of ypT0-T2 tumors (35.8% vs. 22.7%) and a lower rate of ypT3-T4 tumors (57.3% vs. 72.8%; P < .001), lower rate of node-positive disease (36.6% vs. 59.8%, P < .001), and margin-positive resections (13.8% vs. 20.2%, P < .001), but slightly higher 90-day postoperative mortality (4.9% vs. 3.6%, P = .04). Neoadjuvant chemotherapy+ RT was associated with longer overall survival (32.7 vs. 29.8 months, P = .008), and remained independently associated with survival on multivariable analysis (HR = .85, P < .001)., Discussion: In patients with stage II-III pancreatic adenocarcinoma, the addition of neoadjuvant RT to multiagent neoadjuvant CT may be associated with increased rates of node-negative and margin-negative resection, as well as improved overall survival.

Background: Most data on postoperative outcomes among patients with proximal extrahepatic cholangiocarcinoma are reported by single institutions. The purpose of this study was to analyze postoperative outcomes stratified by age and comorbidities., Methods: Patients with proximal extrahepatic cholangiocarcinoma who underwent a resection were identified in the National Cancer Database. Pathologic, postoperative, and survival outcomes were compared based on age and Charlson-Deyo comorbidity index., Results: Among the 1,579 patients, the average age was 66 years, and 9.4% of patients were older than 80 years. Most patients had a Charlson-Deyo score of 0 (72.4%), with the minority having scores of 1 (20.5%) or ≥2 (7.1%). Patients ≥80 years had a higher 90-day mortality rate compared with patients 65 to 79 and <65 years (21.3% vs 12.0% vs 7.4%, P < .001). Patients with a Charlson-Deyo score ≥2 had longer duration of stay, greater likelihood of requiring an unplanned readmission, and a higher 90-day mortality rate compared with patients with a lower comorbidity index. Median survival of patients <65, 65 to 79, and ≥80 years was 31, 24, and 17 months, respectively. A similar trend was seen with increasing Charlson-Deyo score (0: 27 months, 1: 25 months, ≥2: 20 months). On multivariable analysis, age ≥80 years (hazard ratio = 1.52, P = .01) and Charlson-Deyo score ≥2 (hazard ratio = 1.45, P = .01) were associated with poor survival., Conclusion: In patients with proximal extrahepatic cholangiocarcinoma, age ≥80 years and greater comorbidity index are associated with increased risk of 90-day mortality and poor overall survival. This suggests that resections in high-risk patient populations should be approached with caution., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Background: Neoadjuvant chemotherapy is used infrequently in the management of distal pancreatic cancers. We investigated outcomes associated with neoadjuvant chemotherapy or up-front surgery in patients undergoing distal pancreatectomy., Methods: The National Cancer Database (2004-2016) was queried for patients with pancreas cancer who underwent distal pancreatectomy. Demographics, clinical characteristics, postoperative outcomes, pathologic outcomes, and overall survival were analyzed by univariate and multivariate analysis., Results: Six thousand five-hundred and twenty-three patients were included, including 5,643 who underwent up-front distal pancreatectomy and 880 who received neoadjuvant therapy. Factors associated with receipt of neoadjuvant chemotherapy included care at academic/research programs, higher education level, higher clinical T stage, higher clinical N stage, and elevated carbohydrate antigen 19-9 level. Patients who received neoadjuvant therapy had fewer positive lymph nodes, higher margin-negative resection rate, lower 30-day readmission rate, and lower 90-day mortality rate. Patients who received neoadjuvant therapy had longer median overall survival (28.8 vs 22.0 months; P < .001). On multivariate analysis, neoadjuvant therapy remained independently associated with improved survival (hazards ratio, 0.72; 95% confidence inteval, 0.63-0.82; P < .001)., Conclusions: Neoadjuvant therapy in patients with left-sided pancreatic cancers is associated with improved pathologic outcomes as well as longer overall survival. Neoadjuvant therapy should be considered in all patients with PDAC regardless of tumor location., (© 2020 Wiley Periodicals LLC.)

PIK3CA encodes the p110α catalytic subunit of PI3K and is frequently mutated in human cancers, including ∼30% of colorectal cancer. Oncogenic mutations in PIK3CA render colorectal cancers more dependent on glutamine. Here we report that the glutaminase inhibitor CB-839 preferentially inhibits xenograft growth of PIK3CA -mutant, but not wild-type (WT), colorectal cancers. Moreover, the combination of CB-839 and 5-fluorouracil (5-FU) induces PIK3CA -mutant tumor regression in xenograft models. CB-839 treatment increased reactive oxygen species and caused nuclear translocation of Nrf2, which in turn upregulated mRNA expression of uridine phosphorylase 1 (UPP1). UPP1 facilitated the conversion of 5-FU to its active compound, thereby enhancing the inhibition of thymidylate synthase. Consistently, knockout of UPP1 abrogated the tumor inhibitory effect of combined CB-839 and 5-FU administration. A phase I clinical trial showed that the combination of CB-839 and capecitabine, a prodrug of 5-FU, was well tolerated at biologically-active doses. Although not designed to test efficacy, an exploratory analysis of the phase I data showed a trend that PIK3CA -mutant patients with colorectal cancer might derive greater benefit from this treatment strategy as compared with PIK3CA WT patients with colorectal cancer. These results effectively demonstrate that targeting glutamine metabolism may be an effective approach for treating patients with PIK3CA -mutant colorectal cancers and warrants further clinical evaluation. SIGNIFICANCE: Preclinical and clinical trial data suggest that the combination of CB-839 with capecitabine could serve as an effective treatment for PIK3CA -mutant colorectal cancers., (©2020 American Association for Cancer Research.)

Many cancer types reprogram their metabolism to become addicted to glutamine. One of the critical enzymes in the utilization of glutamine in these cells is glutaminase. CB-839 (telaglenastat) is a drug that targets glutaminase that is currently being evaluated in many clinical trials for efficacy in various cancer types that are known to be driven by glutamine metabolism. Despite its use, there are limited assays available for testing the pharmacodynamic on-target effects of CB-839 on the limited, small-volume patient samples that are obtained in early-phase clinical trials. Thus, we developed an assay based on the cellular thermal shift assay technique using AlphaLISA technology to show that CB-839 specifically engages glutaminase in colon cancer cell lines in vitro and in minute quantities of mouse xenograft tumors. Notably, we show that this assay detects CB-839 binding to glutaminase in platelets of patients collected while receiving CB-839 on a clinical trial. This assay may be used to study the pharmacodynamic profile of CB-839 in very small tissue samples obtained from patients on a clinical trial and may be useful in future studies designed to screen other inhibitors of glutaminase., (Copyright © 2020 Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, and Genetics Society of China. Published by Elsevier Ltd. All rights reserved.)

Ketogenic diets induce hepatocyte fatty acid oxidation and ketone body production. To further evaluate how ketogenic diets affect hepatocyte bioenergetic infrastructure, we analyzed livers from C57Bl/6J male mice maintained for 1 month on a ketogenic or standard chow diet. Compared with the standard diet, the ketogenic diet increased cytosolic and mitochondrial protein acetylation and also altered protein succinylation patterns. SIRT3 protein decreased while SIRT5 protein increased, and gluconeogenesis, oxidative phosphorylation, and mitochondrial biogenesis pathway proteins were variably and likely strategically altered. The pattern of changes observed can be used to inform a broader systems overview of how ketogenic diets affect liver bioenergetics.

Diet composition may affect energy metabolism in a tissue-specific manner. Using C57Bl/6J mice, we tested the effect of ketosis-inducing and non-inducing high fat diets on genes relevant to brain bioenergetic infrastructures, and on proteins that constitute and regulate that infrastructure. At the end of a one-month study period the two high fat diets appeared to differentially affect peripheral insulin signaling, but brain insulin signaling was not obviously altered. Some bioenergetic infrastructure parameters were similarly impacted by both high fat diets, while other parameters were only impacted by the ketogenic diet. For both diets, mRNA levels for CREB, PGC1α, and NRF2 increased while NRF1, TFAM, and COX4I1 mRNA levels decreased. PGC1β mRNA increased and TNFα mRNA decreased only with the ketogenic diet. Brain mtDNA levels fell in both the ketogenic and non-ketogenic high fat diet groups, although TOMM20 and COX4I1 protein levels were maintained, and mRNA and protein levels of the mtDNA-encoded COX2 subunit were also preserved. Overall, the pattern of changes observed in mice fed ketogenic and non-ketogenic high fat diets over a one month time period suggests these interventions enhance some aspects of the brain's aerobic infrastructure, and may enhance mtDNA transcription efficiency. Further studies to determine which diet effects are due to changes in brain ketone body levels, fatty acid levels, glucose levels, altered brain insulin signaling, or other factors such as adipose tissue-associated hormones are indicated.

Mitochondrial impairment is commonly found in many diseases such as diabetes, cancer, and Alzheimer disease. We demonstrate that the enzymes responsible for the addition or removal of the O-GlcNAc modification, O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA), respectively, are critical regulators of mitochondrial function. Using a SILAC (stable isotope labeling of amino acids in cell culture)-based proteomics screen, we quantified the changes in mitochondrial protein expression in OGT- and OGA-overexpressing cells. Strikingly, overexpression of OGT or OGA showed significant decreases in mitochondria-localized proteins involved in the respiratory chain and the tricarboxylic acid cycle. Furthermore, mitochondrial morphology was altered in these cells. Both cellular respiration and glycolysis were reduced in OGT/OGA-overexpressing cells. These data demonstrate that alterations in O-GlcNAc cycling profoundly affect energy and metabolite production., (© 2014 by The American Society for Biochemistry and Molecular Biology, Inc.)

Bioenergetic dysfunction occurs in Alzheimer's disease (AD) and mild cognitive impairment (MCI), a clinical syndrome that frequently precedes symptomatic AD. In this study, we modeled AD and MCI bioenergetic dysfunction by transferring mitochondria from MCI, AD and control subject platelets to mtDNA-depleted SH-SY5Y cells. Bioenergetic fluxes and bioenergetics-related infrastructures were characterized in the resulting cytoplasmic hybrid (cybrid) cell lines. Relative to control cybrids, AD and MCI cybrids showed changes in oxygen consumption, respiratory coupling and glucose utilization. AD and MCI cybrids had higher ADP/ATP and lower NAD+/NADH ratios. AD and MCI cybrids exhibited differences in proteins that monitor, respond to or regulate cell bioenergetic fluxes including HIF1α, PGC1α, SIRT1, AMPK, p38 MAPK and mTOR. Several endpoints suggested mitochondrial mass increased in the AD cybrid group and probably to a lesser extent in the MCI cybrid group, and that the mitochondrial fission-fusion balance shifted towards increased fission in the AD and MCI cybrids. As many of the changes we observed in AD and MCI cybrid models are also seen in AD subject brains, we conclude reduced bioenergetic function is present during very early AD, is not brain-limited and induces protean retrograde responses that likely have both adaptive and mal-adaptive consequences.

The effects of exercise are not limited to muscle, and its ability to mitigate some chronic diseases is under study. A more complete understanding of how exercise impacts non-muscle tissues might facilitate design of clinical trials and exercise mimetics. Here, we focused on lactate's ability to mediate changes in liver and brain bioenergetic-associated parameters. In one group of experiments, C57BL/6 mice underwent 7 weeks of treadmill exercise sessions at intensities intended to exceed the lactate threshold. Over time, the mice dramatically increased their lactate threshold. To ensure that plasma lactate accumulated during the final week, the mice were run to exhaustion. In the liver, mRNA levels of gluconeogenesis-promoting genes increased. While peroxisome proliferator-activated receptor-gamma co-activator 1 alpha (PGC-1α) expression increased, there was a decrease in PGC-1β expression, and overall gene expression changes favored respiratory chain down-regulation. In the brain, PGC-1α and PGC-1β were unchanged, but PGC-1-related co-activator expression and mitochondrial DNA copy number increased. Brain tumor necrosis factor alpha expression fell, whereas vascular endothelial growth factor A expression rose. In another group of experiments, exogenously administered lactate was found to reproduce some but not all of these observed liver and brain changes. Our data suggest that lactate, an exercise byproduct, could mediate some of the effects exercise has on the liver and the brain, and that lactate itself can act as a partial exercise mimetic., (© 2013 International Society for Neurochemistry.)

Alzheimer's disease (AD) is a progressive neurodegenerative disease that affects a staggering percentage of the aging population and causes memory loss and cognitive decline. Mitochondrial abnormalities can be observed systemically and in brains of patients suffering from AD, and may account for part of the disease phenotype. In this review, we summarize some of the key findings that indicate mitochondrial dysfunction is present in AD-affected subjects, including cytochrome oxidase deficiency, endophenotype data, and altered mitochondrial morphology. Special attention is given to recently described perturbations in mitochondrial autophagy, fission-fusion dynamics, and biogenesis. We also briefly discuss how mitochondrial dysfunction may influence amyloidosis in Alzheimer's disease, why mitochondria are a valid therapeutic target, and strategies for addressing AD-specific mitochondrial dysfunction., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Mitochondria from persons with Alzheimer's disease (AD) differ from those of age-matched control subjects. Differences in mitochondrial morphology and function are well documented, and are not brain-limited. Some of these differences are present during all stages of AD, and are even seen in individuals who are without AD symptoms and signs but who have an increased risk of developing AD. This chapter considers the status of mitochondria in AD subjects, the potential basis for AD subject mitochondrial perturbations, and the implications of these perturbations. Data from multiple lines of investigation, including epidemiologic, biochemical, molecular, and cytoplasmic hybrid studies, are reviewed. The possibility that mitochondria could potentially constitute a reasonable AD therapeutic target is discussed, as are several potential mitochondrial medicine treatment strategies., (Copyright © 2012 Elsevier Inc. All rights reserved.)

We have performed a kinetic analysis of Ca2+-dependent switching in the complex between calmodulin (CaM) and the IQ domain from neuromodulin, and have developed detailed kinetic models for this process. Our results indicate that the affinity of the C-ter Ca2+-binding sites in bound CaM is reduced due to a approximately 10-fold decrease in the Ca2+ association rate, while the affinity of the N-ter Ca2+-binding sites is increased due to a approximately 3-fold decrease in the Ca2+ dissociation rate. Although the Ca2+-free and Ca2+-saturated forms of the CaM-IQ domain complex have identical affinities, CaM dissociates approximately 100 times faster in the presence of Ca2+. Furthermore, under these conditions CaM can be transferred to the CaM-binding domain from CaM kinase II via a ternary complex. These properties are consistent with the hypothesis that CaM bound to neuromodulin comprises a localized store that can be efficiently delivered to neuronal proteins in its Ca2+-bound form in response to a Ca2+ signal.