Application of Urinary Volatile Organic Compounds (VOCs) for the Diagnosis of Prostate Cancer.

BACKGROUND: Prostate cancer (PCa) screening using serum prostate-specific antigen (PSA) testing has caused unnecessary biopsies and overdiagnosis owing to its low accuracy and reliability. Therefore, there is an increased interest in identifying better PCa biomarkers. Studies showed that trained dogs can discriminate patients with PCa from unaffected men by sniffing urine. We hypothesized that urinary volatile organic compounds (VOCs) may be the source of that odor and could be used to develop urinary VOC PCa diagnosis models. PATIENTS AND METHODS: Urine samples from 55 and 53 biopsy proven PCa-positive and -negative patients respectively were initially obtained for diagnostic model development. Urinary metabolites were analyzed by gas chromatography-mass spectrometry. A PCa diagnosis model was developed and validated using innovative statistical machine-learning techniques. A second set of samples (53 PCa-positive and 22 PCa-negative patients) were used to evaluate the previously developed PCa diagnosis model. RESULTS: The analysis resulted in 254 and 282 VOCs for their significant association (P < .05) with either PCa-positive or -negative samples respectively. Regularized logistic regression analysis and the Firth method were then applied to predict PCa prevalence, resulting in a final model that contains 11 VOCs. Under cross-validation, the area under the receiver operating characteristic curve (AUC) for the final model was 0.92 (sensitivity, 0.96; specificity, 0.80). Further evaluation of the developed model using a testing cohort yielded an AUC of 0.86. As a comparison, the PSA-based diagnosis model only rendered an AUC of 0.54. CONCLUSION: The study describes the development of a urinary VOC-based model for PCa detection.

Risk Factors for Postoperative Fever and Systemic Inflammatory Response Syndrome After Ureteroscopy for Stone Disease.

Introduction: Infectious complications after ureteroscopy (URS) for stone disease lead to emergency department visits, hospitalizations, and other costly health care utilization. The objective of our study was to identify risk factors for postoperative fever (POF) and systemic inflammatory response syndrome (SIRS) after URS for stone disease. Materials and Methods: We performed a retrospective cohort study on 2746 patients who underwent 3298 URS for stone disease at Geisinger from 2008 to 2016. A univariate analysis tested the associations between candidate demographic, preoperative, and intraoperative predictors and the primary outcome of POF (temperature >100.4°F) or SIRS. Variables with a p-value of <0.05 on univariate comparisons were entered into a random-effects logistic regression model. The final model used backward elimination random-effects logistic regression to identify predictors most predictive of POF/SIRS. Results: Overall, 229 (6.9%) of 3298 URS had POF/SIRS. On univariate analysis, individuals with POF/SIRS were older, had higher mean body mass index, higher Charlson Comorbidity Index (CCI), bilateral and larger stones, stone location in the kidney, positive preoperative urine culture, pre-stented, and longer surgical times. In the final model, female gender (adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.19-2.15), surgical time (adjusted OR 1.01, 95% CI 1.0-1.01), CCI ≥2 (adjusted OR 1.86, 95% CI 1.29-2.67), and positive preoperative urine culture (adjusted OR 1.53, 95% CI 1.06-2.22) were the most significant predictors of POF/SIRS. Conclusions: Female gender, longer surgical time, medical complexity, and positive preoperative urine culture are associated with POF/SIRS after URS. These data may be used to identify and counsel high-risk individuals.

Dual targeting of HSP70 does not induce the heat shock response and synergistically reduces cell viability in muscle invasive bladder cancer.

Muscle invasive bladder cancer (MIBC) is a common malignancy and major cause of morbidity worldwide. Over the last decade mortality rates for MIBC have not decreased as compared to other cancers indicating a need for novel strategies. The molecular chaperones HSP70 and HSP90 fold and maintain the 3-dimensional structures of numerous client proteins that signal for cancer cell growth and survival. Inhibition of HSP70 or HSP90 results in client protein degradation and associated oncogenic signaling. Here we targeted HSP70 and HSP90 with small molecule inhibitors that trap or block each chaperone in a low client-affinity "open" conformation. HSP70 inhibitors, VER155008 (VER) and MAL3-101 (MAL), along with HSP90 inhibitor, STA-9090 (STA), were tested alone and in combination for their ability to reduce cell viability and alter protein levels in 4 MIBC cell lines. When combined, VER+MAL synergistically reduced cell viability in each MIBC cell line while not inducing expression of heat shock proteins (HSPs). STA+MAL also synergistically reduced cell viability in each cell line but induced expression of cytoprotective HSPs indicating the merits of targeting HSP70 with VER+MAL. Additionally, we observed that STA induced the expression of the stress-related transcription factor HSF2 while reducing levels of the co-chaperone TTI1.

Mutagenesis and computer modeling studies of a GPCR conserved residue W5.43(194) in ligand recognition and signal transduction for CB2 receptor.

W5.43(194), a conserved tryptophan residue among G-protein coupled receptors (GPCRs) and cannabinoid receptors (CB), was examined in the present report for its significance in CB2 receptor ligand binding and adenylyl cyclase (AC) activity. Computer modeling postulates that this site in CB2 may be involved in the affinity of WIN55212-2 and SR144528 through aromatic contacts. In the present study, we reported that a CB2 receptor mutant, W5.43(194)Y, which had a tyrosine (Y) substitution for tryptophan (W), retained the binding affinity for CB agonist CP55940, but reduced binding affinity for CB2 agonist WIN55212-2 and inverse agonist SR144528 by 8-fold and 5-fold, respectively; the CB2 W5.43(194)F and W5.43(194)A mutations significantly affect the binding activities of CP55940, WIN55212-2 and SR144528. Furthermore, we found that agonist-mediated inhibition of the forskolin-induced cAMP production was dramatically diminished in the CB2 mutant W5.43(194)Y, whereas W5.43(194)F and W5.43(194)A mutants resulted in complete elimination of downstream signaling, suggesting that W5.43(194) was essential for the full activation of CB2. These results indicate that both aromatic interaction and hydrogen bonding are involved in ligand binding for the residue W5.43(194), and the mutations of this tryptophan site may affect the conformation of the ligand binding pocket and therefore control the active conformation of the wild type CB2 receptor. W5.43(194)Y/F/A mutations also displayed noticeable enhancement of the constitutive activation probably attributed to the receptor conformational changes resulted from the mutations.