Faculty Bibliography

We demonstrate the use of 5'-Acrydite oligonucleotides to copolymerize single-cell DNA or RNA into balls of acrylamide gel (BAG). Combining this step with split-and-pool techniques for creating barcodes yields a method with advantages in cost and scalability, depth of coverage, ease of operation, minimal cross-contamination and efficient use of samples. We perform DNA copy number profiling on mixtures of cell lines, nuclei from frozen prostate tumors, and biopsy washes. As applied to RNA, the method has high capture efficiency of transcripts and sufficient consistency to distinguish clearly the expression patterns of cell lines and individual nuclei from neurons dissected from the mouse brain. Using varietal tags (UMIs) to achieve sequence error correction, we show extremely low levels of cross-contamination by tracking source-specific SNVs. The method is readily modified, and we will discuss its adaptability and diverse applications.

BACKGROUND/PURPOSE/OBJECTIVE:Stratification of Gleason score (GS) into three categories (2-6, 7, and 8-10) may not fully utilize its prognostic discrimination, with Gleason pattern 5 (GP5) previously identified as an independent adverse factor. MATERIALS/METHODS/METHODS:Patients treated on RTOG 9202 (n = 1292) or RTOG 9902 (n = 378) were pooled and assessed for association of GS and GP5 on biochemical failure (BF), local failure (LF), distant metastasis (DM), and overall survival (OS). Fine and Gray's regression and cumulative incidence methods were used for univariate and multivariate analyses. RESULTS:With median follow-up of 9.4 years, patients with GS 8-10 with GP5 had worse outcome than GS 4 + 4 for DM on both RTOG9202 (p = 0.038) and RTOG9902 (p < 0.001) with a trend toward worse OS (p = 0.059 and p = 0.089, respectively), but without differences in BF or LF. At 10-years DM was higher by 11% (RTOG 9202) and 18% (RTOG 9902) with GP5 compared to GS 4 + 4. On multivariate analysis restricted to long-term androgen deprivation therapy the presence of GP5 substantially increased distant metastasis (HR = 0.43, 95%CI: 0.24-0.76, p = 0.0039) with a trend toward worse OS (HR:0.74, 95% CI:0.54-1.0, p = 0.052) without association with LF (HR:0.55, 95%CI:0.28-1.09, p = 0.085) or BF (HR:1.15, 95%CI:0.84-1.59, p = 0.39). We did not observed substantial differences between Gleason 3 + 5, 5 + 3, or Gleason 9-10. CONCLUSIONS:These results validate GP5 as an independent prognostic factor which is strongest for DM. As a result GP5 should be considered when stratifying patients with GS 8 and may be a patient population in which to evaluate newly approved systemic therapies or additional local treatments.

Electronic-cigarettes (E-cigs) are marketed as a safe alternative to tobacco to deliver the stimulant nicotine, and their use is gaining in popularity, particularly among the younger population. We recently showed that mice exposed to short-term (12 wk) E-cig smoke (ECS) sustained extensive DNA damage in lungs, heart, and bladder mucosa and diminished DNA repair in lungs. Nicotine and its nitrosation product, nicotine-derived nitrosamine ketone, cause the same deleterious effects in human lung epithelial and bladder urothelial cells. These findings raise the possibility that ECS is a lung and bladder carcinogen in addition to nicotine. Given the fact that E-cig use has become popular in the past decade, epidemiological data on the relationship between ECS and human cancer may not be known for a decade to come. In this study, the carcinogenicity of ECS was tested in mice. We found that mice exposed to ECS for 54 wk developed lung adenocarcinomas (9 of 40 mice, 22.5%) and bladder urothelial hyperplasia (23 of 40 mice, 57.5%). These lesions were extremely rare in mice exposed to vehicle control or filtered air. Current observations that ECS induces lung adenocarcinomas and bladder urothelial hyperplasia, combined with our previous findings that ECS induces DNA damage in the lungs and bladder and inhibits DNA repair in lung tissues, implicate ECS as a lung and potential bladder carcinogen in mice. While it is well established that tobacco smoke poses a huge threat to human health, whether ECS poses any threat to humans is not yet known and warrants careful investigation.

BACKGROUND:In prostate cancer, end points that reliably portend prognosis and treatment benefit (surrogate end points) can accelerate therapy development. Although surrogate end point candidates have been evaluated in the context of radiotherapy and short-term androgen deprivation (AD), potential surrogates under long-term (24 month) AD, a proven therapy in high-risk localized disease, have not been investigated. MATERIALS AND METHODS/METHODS:In the NRG/RTOG 9202 randomized trial (N = 1,520) of short-term AD (4 months) versus long-term AD (LTAD; 28 months), the time interval free of biochemical failure (IBF) was evaluated in relation to clinical end points of prostate cancer-specific survival (PCSS) and overall survival (OS). Survival modeling and landmark analysis methods were applied to evaluate LTAD benefit on IBF and clinical end points, association between IBF and clinical end points, and the mediating effect of IBF on LTAD clinical end point benefits. RESULTS:LTAD was superior to short-term AD for both biochemical failure (BF) and the clinical end points. Men remaining free of BF for 3 years had relative risk reductions of 39% for OS and 73% for PCSS. Accounting for 3-year IBF status reduced the LTAD OS benefit from 12% (hazard ratio [HR], 0.88; 95% CI, 0.79 to 0.98) to 6% (HR, 0.94; 95% CI, 0.83 to 1.07). For PCSS, the LTAD benefit was reduced from 30% (HR, 0.70; 95% CI, 0.52 to 0.82) to 6% (HR, 0.94; 95% CI, 0.72 to 1.22). Among men with BF, by 3 years, 50% of subsequent deaths were attributed to prostate cancer, compared with 19% among men free of BF through 3 years. CONCLUSION/CONCLUSIONS:The IBF satisfied surrogacy criteria and identified the benefit of LTAD on disease-specific survival and OS. The IBF may serve as a valid end point in clinical trials and may also aid in risk monitoring after initial treatment.

The number of solid organ transplantations is increasing worldwide. Major medical advances have allowed for incremented survival in this population, which, because approximately 50% of recipients are over age 50 years, makes for an increasingly older population of transplant survivors. This article discusses controversies and current guidelines related to prostate cancer (PCa) screening, detection, and treatment for men in the general population. The relevant literature is reviewed in order to provide insights on how to optimize PCa screening, detection, and treatment pre- and post-solid organ transplantation. There is compelling evidence that immunosuppression does not increase the risk for the development or progression of PCa following solid organ transplantation. Therefore, PCa screening, detection, or treatment should not be influenced by the impact of immunosuppression on the biology of the disease. Prostate-specific antigen (PSA) appears to be as reliable for PCa screening of transplant candidates and recipients as it is for the general population. There is no consensus on how or when it should be implemented. Evidence is also equivocal as to the suggested waiting time between treatment and transplantation. Surgery and radiation therapy appear to be safe and provide good outcomes for managing PCa in solid organ transplant candidates and recipients. However, certain precautions should be taken with this vulnerable population, especially for kidney transplant patients given the pelvic location of the renal graft. Partial gland ablation of PCa should be considered in appropriate candidates.

PURPOSE/OBJECTIVE:While MRI-Ultrasound Fusion-targeted biopsy (MRF-TB) allows for improved detection of clinically significant prostate cancer (csPCa), concerning numbers of clinically significant disease are still missed. We hypothesize that a number of these are due to the learning curve associated with MRF-TB. We report results of repeat MRF-TB in men with continued suspicion for cancer and the institutional learning curve in detection of csPCa over time. MATERIALS AND METHODS/METHODS:Analysis of 1813 prostate biopsies in a prospectively acquired cohort of men presenting for prostate biopsy over a 4-year period. All men were offered pre-biopsy MRI and assigned a maximum Prostate Imaging - Reporting and Data System version 2 (PI-RADS) score. Biopsy outcomes of men with suspicious region of interest (ROI) were compared. The relationship between time and csPCa detection was analyzed. RESULTS:csPCa detection rate increased 26% over time in men with PI-RADS 4 and 5 (4/5) ROI. On repeat MRF-TB in men with continued suspicion for cancer, 53% of men with PI-RADS 4/5 ROI demonstrated clinically significant discordance from initial MRF-TB, compared to only 23% of men with PI-RADS 1/2 ROI. Significantly less csPCa were missed or under-graded in the most recent biopsies as compared to the earliest biopsies. CONCLUSION/CONCLUSIONS:High upgrade rates on repeat MRF-TB and increasing cancer detection rate over time demonstrate the significant learning curve associated with MRF-TB. Men with low risk or negative biopsies with persistent concerning ROI should be promptly re-biopsied. Improved targeting accuracy with operator experience can help decrease the number of missed csPCa.

Uroplakin (UP) tetraspanins and their associated proteins are major mammalian urothelial differentiation products that form unique 2D-crystals of 16-nm particles ("urothelial plaques") covering the apical urothelial surface. Although uroplakins are highly expressed only in mouse urothelium and are often referred to as being urothelium-specific, they are also expressed in several nonurothelial cell types in stomach, kidney, prostate, epididymis, testis/sperms and ovary/oocytes. In oocytes, uroplakins co-localize with CD9 on cell surface and multivesicular body-derived exosomes, and the cytoplasmic tail of UPIIIa undergoes a conserved fertilization-dependent, Fyn-mediated tyrosine-phosphorylation that also occurs in Xenopus laevis eggs. Uroplakin knockout and antibody blocking reduce mouse eggs' fertilization rate in in vitro fertilization assays, and UPII/IIIa double-knockout mice have a smaller litter size. Phylogenetic analyses showed that uroplakin sequences underwent significant mammal-specific changes. These results suggest that, by mediating signal transduction and modulating membrane stability that do not require 2D-crystal formation, uroplakins can perform conserved and more ancestral fertilization functions in mouse and frog eggs. Uroplakins acquired the ability to form 2D- crystalline plaques during mammalian divergence enabling them to perform additional functions, including umbrella cell enlargement and the formation of permeability and mechanical barriers, in order to protect/modify the apical surface of the modern-day mammalian urothelium.

OBJECTIVE:To provide insights into the long-term impact of radical retro-pubic prostatectomy (ORRP) on LUTS which are age and prostate dependent and adversely impact quality of life. METHODS:1,995 men undergoing ORRP enrolled in a prospective longitudinal outcomes study. The American Urological Association symptom index (AUASI) was self-administered before ORRP and at pre-determined time-points after surgery. A multivariate generalized linear model was used to evaluate the association of time since ORRP with AUASS. McNemar's test and paired sample t-tests were used to assess whether the proportion of men with clinically significant LUTS (CSLUTS) defined by an American Urological Association symptom score (AUASS) >7 or mean AUASS differed significantly between the time-dependent assessments, respectively. RESULTS:The 15 year mean adjusted AUASS was similar to baseline (7.00 vs. 6.85, p=0.66). Throughout the 15 years of follow-up, the proportion of men with CSLUTS was lower than baseline with the exception of the 3 month and 15 year assessments. Among men with baseline clinically insignificant LUTS (CILUTS), the mean adjusted AUASS at 15 years was significantly greater than baseline (6.09 vs. 3.19, p<0.001). Among men with baseline CSLUTS, ORRP led to a significant decrease in mean adjusted AUASS between baseline and 15 years (13.26 vs. 8.67, p<0.001). CONCLUSIONS:ORRP favorably affects the long-term natural history of LUTS. The long-term economic and quality of life benefits of ORRP on LUTS should inform the risks and benefits of RP for treatment of localized prostate cancer.