Elraiyah, Tarig

Abstract Context The extent to which some pharmacological interventions reduce or increase the risk of biochemical conversion to type 2 diabetes mellitus (T2DM) in at-risk individuals is unclear. Methods We searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, the Cochrane Database of Systematic Reviews, and Scopus through 24 August 2017 for randomized controlled trials evaluating the effect of drugs suspected to modify the risk of biochemical conversion to T2DM. Results We included 43 trials with 192,156 subjects (mean age, 60 years; 56% men; mean body mass index, 30.4 kg/m2). α-Glucosidase inhibitors, angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, metformin, orlistat, phentermine/topiramate, and pioglitazone significantly reduced the risk of biochemical conversion to T2DM, whereas statins and nateglinide increased the risk. There was insufficient direct evidence regarding the effects of sulfonylureas, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors, and sodium-glucose cotransporter-2 inhibitors. Most trials were brief and evaluated this outcome during treatment without a withdrawal or washout period. Conclusions Several drugs modify the risk of biochemical conversation to T2DM, although whether this effect is persistent and clinically relevant is unclear. Future studies need to focus on cardiovascular disease prevention, mortality, and patient-important outcomes instead of biochemical conversion to T2DM.

Clinical studies have identified specific genetic variants in dihydropyrimidine dehydrogenase (DPD; DPYD gene) as predictors of severe adverse toxicity to the commonly used chemotherapeutic 5‐fluorouracil (5‐FU); however, these studies have focused on European and European‐American populations. Our laboratory recently demonstrated that additional variants in non‐European haplotypes are predictive of 5‐FU toxicity. The objective of this study was to identify potential risk variants in an understudied East African population relevant to our institution's catchment area. The DPYD protein‐coding region was sequenced in 588 individuals of Somali or Kenyan ancestry living in central/southeast Minnesota. Twelve novel nonsynonymous variants were identified, seven of which significantly decreased DPD activity in vitro. The commonly reported toxicity‐associated variants, *2A, D949V, and I560S, were not detected in any individuals. Overall, this study demonstrates a critical limitation in our knowledge of pharmacogenetic predictors of 5‐FU toxicity, which has been based on clinical studies conducted in populations of limited diversity.

Abstract The antimetabolite 5-fluorouracil (5-FU) is one of the most widely used chemotherapy drugs. Dihydropyrimidine dehydrogenase (DPD) is a major determinant of 5-FU response and toxicity. Although DPYD variants may affect 5-FU metabolism, they do not completely explain the reported variability in DPD function or the resultant differences in treatment response. Here, we report that H3K27 trimethylation (H3K27me3) at the DPYD promoter regulated by Ezh2 and UTX suppresses DPYD expression by inhibiting transcription factor PU.1 binding, leading to increased resistance to 5-FU. Enrichment of H3K27me3 at the DPYD promoter was negatively correlated with both DPYD expression and DPD enzyme activity in peripheral blood specimens from healthy volunteers. Lastly, tumor expression data suggest that DPYD repression by Ezh2 predicts poor survival in 5-FU–treated cancers. Collectively, the findings of the present article suggest that a previously uncharacterized mechanism regulates DPD expression and may contribute to tumor resistance to 5-FU. Cancer Res; 76(21); 6362–73. ©2016 AACR.

AbstractContext:Exogenous dehydroepiandrosterone (DHEA) therapy has been proposed to replenish the depletion of endogenous DHEA and its sulfate form, which occurs with advancing age and is thought to be associated with loss of libido and menopausal symptoms.Objective:We conducted a systematic review and meta-analysis to summarize the evidence supporting the use of systemic DHEA in postmenopausal women with normal adrenal function.Methods:We searched MEDLINE, EMBASE, PsycInfo, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus through January 2014. Pairs of reviewers, working independently, selected studies and extracted data from eligible randomized controlled trials (RCTs). We used the random-effects model to pool across studies and evaluated heterogeneity using the I2 statistic.Results:We included 23 RCTs with moderate to high risk of bias enrolling 1188 women. DHEA use was not associated with significant improvement in libido or sexual function (standardized mean difference, 0.35; 95% confidence interval, −0.02 to 0.73; P value = .06; I2 = 62%). There was also no significant effect of DHEA on serious adverse effects, serum lipids, serum glucose, weight, body mass index, or bone mineral density. This evidence warranted low confidence in the results, mostly due to imprecision, risk of bias, and inconsistency across RCTs.Conclusions:Evidence warranting low confidence suggests that DHEA administration does not significantly impact sexual symptoms or selected metabolic markers in postmenopausal women with normal adrenal function.

SummaryBackgroundThe presence of germline mutations in sporadic pheochromocytomas and paragangliomas (SPPs) may change the clinical management of both index patients and their family members. However, the frequency of germline mutations in SPPs is unknown.ObjectiveTo describe the frequency of germline mutations in SPPs and to determine the value of testing index patients and their family members for these mutations.MethodsWe searched databases through June 2012 for observational studies of patients with SPPs who underwent germline genetic testing. The criteria used to define sporadic tumours were (i) the absence of a family history of PCC/PG, (ii) the absence of syndromic features, (iii) the absence of bilateral disease and (iv) the absence of metastatic disease.ResultsWe included 31 studies including 5031 patients (mean age 44). These patients received tests for any of these ten mutations: SDHAF2, RET, SDHD, SDHB, SDHC, VHL, TMEM127, MAX, Isocitrate Dehydrogenase Mutation (IDH) and NF1. The overall frequency of germline mutation in SPP was 551 of 5031 or 11%; when studies with patients fulfilling four criteria for sporadic tumours were used, the frequency was 171 of 1332 or 13%. The most common germline mutation was SDHB 167 of 3611 (4·6%). Little outcome data were available to assess the benefits of genetic testing in index cases and family members.ConclusionsThe frequency of germline mutations in SPPs is approximately 11–13% and the most common mutations affect less than 1 in 20 patients. The value of testing for germline mutations in patients with SPPs and their family members is unknown, as the balance of potential benefits and harms remains unclear.