BPH: a tell-tale sign of prostate cancer? Results from the Prostate Cancer and Environment Study (PROtEuS)

Causal relationship between prostatic diseases and prostate cancer: a mendelian randomization study

BACKGROUND

Although it is thought that prostatitis or benign prostatic hyperplasia (BPH) is related to prostate cancer (PCa), the underlying causal effects of these diseases are unclear.

METHODS

We assessed the causal relationship between prostatitis or BPH and PCa using a two-sample Mendelian randomization (MR) approach. The data utilized in this study were sourced from genome-wide association study. The association of genetic variants from cohorts of prostatitis or BPH and PCa patients was determined using inverse-variance weighted and MR Egger regression techniques. The direction of chance was determined using independent genetic variants with genome-wide significance (P < 5 × 10-6). The accuracy of the results was confirmed using sensitivity analyses.

RESULTS

MR analysis showed that BPH had a significant causal effect on PCa (Odds Ratio = 1.209, 95% Confidence Interval: 0.098-0.281, P = 5.079 × 10- 5) while prostatitis had no significant causal effect on PCa (P > 0.05). Additionally, the pleiotropic test and leave-one-out analysis showed the two-sample MR analyses were valid and reliable.

CONCLUSIONS

This MR study supports that BPH has a positive causal effect on PCa, while genetically predicted prostatitis has no causal effect on PCa. Nonetheless, further studies should explore the underlying biochemical mechanism and potential therapeutic targets for the prevention of these diseases.

Alcohol dehydrogenase expression patterns in normal prostate, benign prostatic hyperplasia, and prostatic adenocarcinoma in African American and Caucasian men

BACKGROUND

In situ metabolism of ethanol by alcohol dehydrogenases (ADHs) contributes to oxidative damage of cells and DNA and has been linked to carcinogenesis in numerous epithelial tissues. The goal of this study was to determine expression patterns of ADH1 and ADH7 isozymes in normal, hyperplastic (benign prostatic hyperplasia [BPH]) and neoplastic (prostate cancer [PCa]) prostate. Furthermore, racial differences in ADH expression between African Americans and Caucasians were investigated.

METHODS

ADH expression patterns were characterized by density analysis of ADH immunohistochemistry (n = 21) and real-time RT-PCR of total RNAs by laser-capture microdissection (n = 10) and whole tissue formalin-fixed paraffin embedded prostate biopsies (n = 63).

RESULTS

ADH protein is found in normal prostate and is primarily associated with glandular epithelium. Transcripts of ADH1B are suppressed in PCa compared to BPH (p = 0.0095). Racial differences in ADH7 transcripts exist between African American and Caucasian men. A total of 57.6% of biopsies from African American prostates have detectable ADH7 messenger RNA (mRNA) transcripts compared to the 13.3% of Caucasian prostate biopsies with detectable transcripts (p = 0.0005). This increased frequency of detection contributes to higher mean ADH7 mRNA transcript levels in African Americans (p = 0.001).

CONCLUSIONS

To our knowledge this study is the first to report downregulation of ADH1B in neoplastic prostate at the transcriptional level, suggesting protective regulatory functions. ADH7 transcripts were not detectable in all samples and was found in higher frequency and amount in our African American samples. Racial differences in ADH7 within the prostate is a novel finding and should be investigated further.

Prostate Cancer Risk and Prognostic Influence Among Users of 5-Alpha-Reductase Inhibitors and Alpha-Blockers: A Systematic Review and Meta-Analysis

We systematically assessed the effect of 5-alpha-reductase inhibitors (5-ARIs) and/or alpha-blockers use on prostate cancer (CaP) incidence and outcomes, including CaP pathologic progression, CaP-specific mortality, and all-cause mortality. 5-ARIs but not alpha-blockers decreased risk of overall CaP, low grade CaP (Gleason < 7), and delayed CaP pathologic progression. Both 5-ARIs and alpha-blockers had no significant impact on risk of high grade CaP (Gleason ≥ 7), CaP-specific mortality, or all-cause mortality. Our result suggested that finasteride should be given for at least 4 years if used for preventing CaP.

Risk stratification for benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) represents an important public health problem in ageing men due to frequently associated lower urinary tract symptoms (LUTS), which may impair quality of life. BPH is also a progressive disease, mainly characterized by a worsening of LUTS over time, and in some patients by the occurrence of serious outcomes such as acute urinary retention and need for BPH-related surgery. The management of BPH and LUTS in men should move forward its focus on symptom control only. Indeed, the goals of therapy for BPH are not only to improve bothersome LUTS but also to identify those patients at risk of unfavourable outcomes in order to optimize their management and reduce complications. Risk stratification and tailored treatment should improve the reductions in both symptoms and the long-term consequences of BPH and BPH treatments. To do this, clinicians need to know possible factors that may support the develop of PBH and possible risks due to the BPH itself.

Medical management of benign prostatic hyperplasia: Results from a population-based study

INTRODUCTION

In men with bothersome lower urinary tract symptoms (LUTS), medical treatment usually represents the first line. We examined the patterns of medical management of benign prostatic hyperplasia (BPH) in the Montreal metropolitan area, within the context of a case control study focusing on incident prostate cancer.

METHODS

Cases were 1933 men with incident prostate cancer. Population controls included 1994 age-matched men. In-person interviews collected sociodemographic characteristics and medical history, including BPH diagnosis, its duration, and type of medical treatment received. Baseline characteristics were compared by the chi-square likelihood test for categorical variables and by the students t-test for continuously coded variables.

RESULTS

Overall, 1120 participants had history of BPH; of those 53.7% received medical treatment for BPH. Individuals with medically treated BPH, compared to individuals with medically untreated BPH, were older at index date [mean: 66.9 vs. 64.9 years, p<0.001)] and at diagnosis of BPH [mean: 62.3 vs. 60.3 years, p<0.001]. They also had a longer duration of BPH-history [mean: 4.7 vs. 4.0 years, p=0.02]. Regarding medical treatment, mono-therapy was more often used than combination therapy [87.6% vs. 12.4%, p<0.001]. Alpha-blockers (69.9%) were most commonly used as monotherapy, followed by 5alpha-reductase inhibitors (5ARIs) (26.6%). Alpha-blockers plus 5ARIs were the most common combination therapy (97.3%).

CONCLUSIONS

Despite evidence from randomized, controlled trials for better efficacy with use of combination therapy, monotherapy consisting of alpha-blockers or 5ARI, in that order, is most frequently used. Additionally, 5ARI use was more common than previously reported (27% vs. 15%).