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Summary Background The international Intermediate Clinical Endpoints in Cancer of the Prostate working group has established metastasis-free survival as a surrogate for overall survival in localised prostate cancer based on the findings of 19 predominantly radiotherapy-based trials. We sought to comprehensively assess aggregate trial-level performance of commonly reported intermediate clinical endpoints across all randomised trials in localised prostate cancer. Methods For this meta-analysis, we searched PubMed for all trials in localised or biochemically recurrent prostate cancer published between Jan 1, 1970, and Jan 15, 2020. Eligible trials had to be randomised, therapeutic, reporting overall survival and at least one intermediate clinical endpoint, and with a sample size of at least 70 participants. Trials of metastatic disease were excluded. Intermediate clinical endpoints included biochemical failure, local failure, distant metastases, biochemical failure-free survival, progression-free survival, and metastasis-free survival. Candidacy for surrogacy was assessed using the second condition of the meta-analytical approach (ie, correlation of the treatment effect of the intermediate clinical endpoint and overall survival), using R2 weighted by the inverse variance of the log intermediate clinical endpoint hazard ratio. The intermediate clinical endpoint was deemed to be a surrogate for overall survival if R2 was 0·7 or greater. Findings 75 trials (53 631 patients) were included in our analysis. Median follow-up was 9·1 years (IQR 5·7–10·6). Biochemical failure (R2 0·38 [95% CI 0·11–0·64]), biochemical failure-free survival (R2 0·12 [0·0030–0·33]), biochemical failure and clinical failure (R2 0·28 [0·0045–0·65]), and local failure (R2 0·085 [0·00–0·37]) correlated poorly with overall survival. Progression-free survival (R2 0·46 [95% CI 0·22–0·67]) showed moderate correlation with overall survival, and metastasis-free survival (R2 0·78 [0·59–0·89]) correlated strongly. Interpretation Intermediate clinical endpoints based on biochemical and local failure did not meet the second condition of the meta-analytical approach and are not surrogate endpoints for overall survival in localised prostate cancer. Our findings validate metastasis-free survival as the only identified surrogate endpoint for overall survival to date. Funding Prostate Cancer Foundation and National Institutes of Health.

PURPOSE/OBJECTIVE(S) Cannabis use rates are increasing throughout the United States along with shifts in state-level policy. Patients with cancer use cannabis for a broad range of indications, but there is limited quality data to support many of these uses. To date, few studies have sought to understand cannabis use in populations of patients served by radiation oncology departments. MATERIALS/METHODS Standardized electronic medical record prompts were used by clinicians for cannabis history documentation for 1050 adult patients seen for initial consultation or follow-up between 10/2020 and 2/2021 at an academic radiation oncology department. Cannabis use data, including recency/frequency of use, indication, and mode of administration, were later gathered using the Michigan Radiation Oncology Analytics Resource (M-ROAR) under an IRB-approved protocol. Cannabis use characteristics were summarized, and logistic regression was used to explore associations between age and gender and recent cannabis use. RESULTS In total, 54 (5.1%) of 1050 unique patients declined to answer questions about cannabis use. Of the remaining 996 patients, 106 (10.6%) endorsed recent cannabis use (≤1 month ago), 71 (7.1%) noted remote use (> 1 month ago), and 819 (82.2%) denied history of cannabis use. The median age of those with recent cannabis use was 59.5 (IQR: 49.7-66.4) vs. 65.4 (IQR: 57.1-73.5) in all others. A multivariable logistic regression analysis revealed an association between age (OR 0.96; 95% CI: 0.95-0.97; P < 0.001) but not gender (male OR 1.24; 95% CI: 0.82-1.88; P = 0.310) and recent cannabis use. Patients noted pain (46.2%), anxiety (23.6%), insomnia (17.9%), "for the high" (17.0%), nausea (15.1%), poor appetite (14.2%), "to fight cancer" (4.7%), and depression (1.9%) as indications for use. The most common mode of administration was inhalation via smoking (47.2%), followed by oral (edibles, 36.8%), topical (15.1%), oral (drinks, 4.7%), vaping (3.8%), sublingual (1.0%), and rectal (1.0%). Most patients used cannabis daily (58.5%). Only 4 individuals (3.8%) noted use multiple times daily, while the remainder endorsed weekly (20.8%) or less than weekly (17.0%) use. CONCLUSION Approximately 10% of patients seen in a radiation oncology department reported recent cannabis use for a variety of reasons. These findings suggest a need for: 1) collection of cannabis use history in radiation oncology departments, 2) efforts to destigmatize cannabis use to facilitate frank discussions between patients and providers, 3) patient education about the fact that cannabis is not an evidence-based cancer treatment, 4) recommendation against inhaled forms of cannabis, which may carry risk of pulmonary toxicity, and 5) careful application of proven therapies to address symptoms when appropriate to provide alternatives to cannabis. Further research is needed to assess changes in cannabis use patterns over the course of cancer treatment and to evaluate risks and benefits of cannabis use in patients with cancer.

Black men die more often of prostate cancer yet, interestingly, may derive greater survival benefits from immune-based treatment with sipuleucel-T. Since no signatures of immune-responsiveness exist for prostate cancer, we explored race-based immune-profiles to identify vulnerabilities. Here we show in multiple independent cohorts comprised of over 1,300 patient samples annotated with either self-identified race or genetic ancestry, prostate tumors from Black men or men of African ancestry have increases in plasma cell infiltrate and augmented markers of NK cell activity and IgG expression. These findings are associated with improved recurrence-free survival following surgery and nominate plasma cells as drivers of prostate cancer immune-responsiveness., A recent report suggested Black men with prostate cancer were more responsive to immunotherapy. Here, the authors analysed prostate cancer gene expression profiles and show tumours from Black men and men with African ancestry have an increased proportion of plasma cells compared to those of White men and this correlates with improved outcome following treatment.

Multiple factors influence the risk of developing pneumonitis after radiation therapy (RT) for lung cancer, but few resources exist to guide clinicians in predicting risk in an individual patient treated with modern techniques. We analyzed toxicity data from a state-wide consortium to develop an integrated pneumonitis risk model.All patients (N = 1302) received conventionally fractionated RT for stage II-III non-small cell lung cancer between April 2012 and July 2019. Pneumonitis occurring within 6 months of treatment was graded by local practitioners and collected prospectively from 27 academic and community clinics participating in a state-wide quality consortium. Pneumonitis was modeled as either grade ≥2 (G2+) or grade ≥3 (G3+). Logistic regression models were fit to quantify univariable associations with dose and clinical factors, and stepwise Akaike information criterion-based modeling was used to build multivariable prediction models.The overall rate of pneumonitis of any grade in the 6 months following RT was 16% (208 cases). Seven percent of cases (n = 94) were G2+ and1% (n = 11) were G3+. Adjusting for incomplete follow-up, estimated rates for G2+ and G3+ were 14% and 2%, respectively. In univariate analyses, gEUD, V5, V10, V20, V30, and mean lung dose (MLD) were positively associated with G2+ pneumonitis risk, whereas current smoking status was associated with lower odds of pneumonitis. G2+ pneumonitis risk of ≥22% was independently predicted by MLD of ≥20 Gy, V20 of ≥35%, and V5 of ≥75%. In multivariate analyses, the lung V5 metric remained a significant predictor of G2+ pneumonitis, even when controlling for MLD, despite their close correlation. For G3+ pneumonitis, MLD and V20 were statistically significant predictors. Number of patient comorbidities was an independent predictor of G3+, but not G2+ pneumonitis.We present an analysis of pneumonitis risk after definitive RT for lung cancer using a large, prospective dataset. We incorporate comorbidity burden, smoking status, and dosimetric parameters in an integrated risk model. These data may guide clinicians in assessing pneumonitis risk in individual patients.

Purpose/objective(s) Guideline and clinical adoption of new radiotherapeutic approaches commonly requires 5-10 years of follow-up in randomized trials to ensure long-term safety. This is resource intensive and slows the pace of advancement. We hypothesized that the relative risk (RR) of radiation-induced gastrointestinal (GI) or genitourinary (GU) toxicity would remain similar or decrease overtime with long-term follow-up. Materials/methods PubMed and Embase were systematically searched for randomized trials evaluating changes in radiotherapy (RT; hypofractionation, dose escalation, change in field size) for localized prostate cancer published between 1970 and 2020. Yearly toxicity estimates were digitally extracted for GI and GU toxicity. Short- and long-term toxicity were defined as toxicity arising in years 1-3 and 5-10 post-RT, respectively. RR differences of toxicity between trial arms were calculated, and differences between short- and long-term relative risk measures of toxicity were compared using paired sample Wilcoxon signed-rank tests weighted by trial size. Results Median follow-up was 6 years (range 3-16) of the included 29 trials (n = 18,069 men). Of trials that reported risk group (67%), 90% of patients had intermediate and high-risk disease, and 57% of patients received ADT. There was no evidence of an increase in the RR of any grade of GI or GU toxicity with follow-up beyond 3 years. The mean RR point estimate of short- vs long-term GI and GU toxicity consistently decreased over time, which was represented by negative values for all grades. Mean differences (late RR - early RR) for grade 1, 2+ and 3+ GI toxicity were (-0.12, P Conclusion While toxicity events may continue to occur over time, the relative difference at later time points is similar or lower compared to early time points. Thus, our data does not support concerns for very late relative increases in radiation-induced toxicity. Physician reported toxicity assessed up to 3 years post-treatment is likely sufficient to establish safety following alternative radiotherapy dose/fractionation schedules and target volumes in prostate cancer.

Enterocyte cholesterol homeostasis reflects aggregated rates of sterol synthesis, efflux, and uptake from plasma and gut lumen. Cholesterol synthesis and LDL uptake are coordinately regulated by sterol regulatory element-binding proteins (SREBP), whereas sterol efflux is regulated by liver X receptors (LXR). How these processes are coordinately regulated in enterocytes, the site of cholesterol absorption, is not well understood. Here, we treat mice with ezetimibe to investigate the effect of blocking cholesterol absorption on intestinal SREBPs, LXRs, and their effectors. Ezetimibe increased nuclear SREBP-2 8-fold. HMG-CoA reductase (HMGR) and LDL receptor (LDLR) mRNA levels increased less than 3-fold, whereas their protein levels increased 30- and 10-fold, respectively. Expression of inducible degrader of LDLR (IDOL), an LXR-regulated gene that degrades LDLRs, was reduced 50% by ezetimibe. Coadministration of ezetimibe with the LXR agonist T0901317 abolished the reduction in IDOL and prevented the increase in LDLR protein. Ezetimibe-stimulated LDLR expression was independent of proprotein convertase subtilisin/kexin type 9 (PSCK9), a protein that degrades LDLRs. To maintain cholesterol homeostasis in the face of ezetimibe, enterocytes boost LDL uptake by increasing LDLR number, and they boost sterol synthesis by increasing HMGR and other cholesterologenic genes. These studies reveal a hitherto undescribed homeostatic network in enterocytes triggered by blockade of cholesterol absorption.

Glucose absorption in the small intestine is mediated by sodium dependent glucose cotransporter 1 (SGLT-1) and glucose transporter-2 (GLUT2), and is potentially linked to sweet taste receptor (STR) signaling and incretin hormone secretion. Both glucose absorption and expression of SGLT-1 are increased in obese rats, but human data is lacking. This study aimed to examine intestinal glucose absorption inmorbidly obese humans, and its relationship to glycemia, incretin responses, SGLT-1, GLUT2, and STR expression. Methods: 17 nondiabetic, morbidly obese subjects (5M:12F; 45 ± 3yrs, BMI: 48 ± 4kg/m2) and 11 lean controls (10M:1F; 44 ± 6yrs, BMI: 25 ± 1kg/m2) underwent endoscopic duodenal biopsies prior to intraduodenal glucose infusion (30g glucose over 30 min, with 3g 3-O-methylglucose (3-OMG) to estimate glucose absorption). Blood glucose and plasma concentrations of 3OMG, glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP1), insulin, and glucagon were measured over 240 min. Absolute expression of SGLT-1, GLUT2 and STR (T1R2) transcripts was quantified by PCR. Results: Both the rate of glucose absorption, as assessed by the rise in plasma 3-OMG concentrations (P

BACKGROUND: Ezetimibe is a widely-used drug that lowers plasma cholesterol by blocking NPC1L1-mediated sterol absorption in small intestine. Enterocyte cholesterol homeostasis is controlled by the aggregated rates of sterol synthesis, efflux, and uptake from plasma and gut lumen. Endogenous cholesterol synthesis and low density lipoprotein (LDL) uptake are coordinately regulated by transcription factors termed Sterol Regulatory Element-Binding Proteins (SREBPs). Liver-X-receptors (LXRs), another family of transcription factors, are activated by sterols and control other aspects of sterol metabolism, especially cholesterol efflux. How blockade of cholesterol absorption by ezetimibe (EZE) affects intestinal SREBPs, LXRs, and key effector molecules, such as LDL Receptor (LDLR) and HMG-CoA Reductase (HMGR) is unknown. AIM: To study the effect of EZE on regulatory molecules that control sterol synthesis and LDL uptake in small intestine. METHODS: C57BL/6 mice were fed a chow diet with indicated drugs. Liver and small intestine were harvested. Jejunal enterocytes were isolated, and tissues fractionated for immunoblotting, which were quantified by densitometry. mRNAs were quantified by qPCR and microarray analysis. RESULTS: Feeding EZE increased active nuclear SREBP-2 by 8-fold in intestine, leading to increases in mRNAs for HMGR and LDLR by 1.3-fold +/0.03 (P

SummaryInjection of the peptide hormone ghrelin stimulates food intake in mice and humans. However, mice born without ghrelin demonstrate no significant loss of appetite. This paradox suggests either that compensation develops in mice born without ghrelin or that ghrelin is not essential for appetite control. To distinguish these possibilities, we generated transgenic mice (Ghrl-DTR) that express the diphtheria toxin receptor in ghrelin-secreting cells. Injection of diphtheria toxin in adulthood ablated ghrelin cells and reduced plasma ghrelin by 80%–95%. Ghrelin cell-ablated mice exhibited no loss of appetite or body weight and no resistance to a high-fat diet. To stimulate food intake in mice by ghrelin injection, we had to raise plasma levels many-fold above normal. Like germline ghrelin-deficient mice, the ghrelin cell-ablated mice developed profound hypoglycemia when subjected to prolonged calorie restriction, confirming that ghrelin acts to maintain blood glucose under famine conditions.