Evidence-based meta-analysis of pharmacotherapy for benign prostatic hypertrophy

Targeting androgen receptor for prostate cancer therapy: From small molecules to PROTACs

Prostate cancer (PCa) remains a serious type of cancer for men worldwide. The majority of new PCa cases are associated with androgen receptor (AR) hyperactivity. Various AR-targeting molecules that suppress its activity have been discovered. In this review, we present the already marketed antiandrogens and a selection of structurally and chemically interesting AR-targeting compounds, from a pharmacochemical perspective. Focus has been placed on the applied design approaches, structural evolution and structure-activity relationships of the most prominent compound classes. Passing from the traditional steroidal AR antagonists to the modern AR-targeting proteolysis targeting chimeras (PROTACs), we intend to provide a comprehensive overview on AR-targeting molecules for PCa treatment.

Prostate cancer specific mortality after 5α-reductase inhibitors medication in benign prostatic hyperplasia patients: systematic review and meta-analysis

BACKGROUND

Our study was conducted to investigate the effect of 5-ARI on the death rate from prostate cancer by means of an updated meta-analysis using related data.

METHODS

We did comprehensive literature searches using the PubMed, Embase, and Cochrane databases through July 2019. We evaluated the risk of bias in such studies using the ROBINS-I tool and analyzed deaths from cancer and deaths from all causes using HR.

RESULTS

The meta-analysis included 11 studies. The pooled overall HRs for cancer-specific deaths between 5-ARI treatment versus non-exposed groups were 0.937 (95% CI: 0.730, 1.201). In the subgroup moderator analysis, the number of patients and additional medication variables were significantly associated with deaths from all causes (p = 0.022 and p = 0.005, respectively). For detecting the publication bias or small-study effect in the included studies, we performed Begg and Mazumdar's correlation test (0.851 and 0.573) and Egger's regression coefficient test (0.035 and 0.245) and ​suggested that there was no evidence of publication bias or small-study effect in this meta-analysis.

CONCLUSIONS

Our study indicated that exposure to 5-ARI had no close association between the overall death rate or cancer-specific deaths. To confirm these results, well-designed prospective studies with large samples are required.

Association of finasteride with prostate cancer: A systematic review and meta-analysis

BACKGROUND

The Prostate Cancer Prevention Trial has shown a protective effect of finasteride on prostate cancer, but it also showed that finasteride can increase the risk of high-grade prostate cancer. Several studies have investigated the relationship between finasteride and prostate cancer, but these studies have shown inconsistent results.

ETHICS

The protocol was approved by the institutional review board of each study center. Written informed consent will be obtained from all patients before registration, in accordance with the Declaration of Helsinki.

METHODS

We performed a systematic literature review and meta-analysis to assess the association between finasteride and prostate cancer. Systematic literature searches were conducted using PubMed, EMBASE, Science Direct/Elsevier, MEDLINE, CNKI, and the Cochrane Library up to October 2018 to identify studies that involved the relationship between finasteride and prostate cancer. Meta-analysis was performed using Review Manager and Stata software. Combined ORs were identified with 95% confidence intervals (95% CI) in a random or fixed effects model.

RESULTS

Eight studies were identified, including 54,335 cases of patients that used finasteride and 9197 patients who served as placebo controls. Our results illustrate that there is a significant correlation between finasteride use and prostate cancer with combined ORs of 0.70 [0.51, 0.96]. A significant correlation between finasteride use and high-grade prostate cancer was also observed with combined ORs of 2.10 [1.85, 2.38].

CONCLUSIONS

This study confirms that finasteride significantly reduced the risk of prostate cancer; however, the malignant degree of prostate cancer was increased. Studies with larger sample sizes are needed to better clarify the correlation between finasteride use and prostate cancer.

Association between 5α-reductase inhibitors therapy and incidence, cancer-specific mortality, and progression of prostate cancer: evidence from a meta-analysis

5α-reductase inhibitors (5-ARI) are widely employed for the treatment of benign prostatic hyperplasia. It has been noted that 5-ARI exhibit the potential to attenuate the risk of prostate cancer, but consistent agreement has not been achieved. Moreover, the effect of 5-ARI on cancer-specific mortality and progression of prostate cancer remains unclear. Therefore, the goal of the current meta-analysis was to elucidate the impact of 5-ARI on the incidence and progression of prostate cancer. We searched for all studies assessing the effect of 5-ARI on risk of prostate cancer in PubMed, Embase, Medline, and Cochrane Library databases. Pooled relative risk (RR) and corresponding 95% confidence intervals (CIs) were accepted to evaluate the association between 5-ARI and the risk of prostate cancer. Synthetic results implied that subjects who accepted 5-ARI compared with the placebo group experienced a distinctly weakened overall incidence of prostate cancer (RR = 0.74; 95% CI: 0.66–0.82; P < 0.001). Subgroup analyses further revealed that 5-ARI reduction of the incidence of prostate cancer was limited to low-grade (Gleason score 2–6; RR = 0.68; 95% CI: 0.57–0.81; P < 0.001) and intermediate-grade tumors (Gleason score 7; RR = 0.81; 95% CI: 0.67–0.97; P = 0.023), but not high-grade tumors (Gleason score >7; RR = 1.19; 95% CI: 0.98–1.43; P = 0.069). The results also showed that 5-ARI treatment did not significantly alter prostate cancer-specific mortality (RR = 1.0; 95% CI: 0.95–1.05; P = 0.916). In addition, it was worth noting that 5-ARI treatment acted in a protective role that presented a dramatic benefit to delay the progression of low-risk tumors (RR = 0.58; 95% CI: 0.43–0.78; P < 0.001).

Herbal Medicine Ninjin'yoeito in the Treatment of Sarcopenia and Frailty

Frailty and sarcopenia have recently gained considerable attention in terms of preventive care in Japan, which has an ever-increasing aging population. Sarcopenia is defined as atrophy of skeletal muscles caused by the age-related decrease in growth hormone/insulin-like growth factor and sex hormones. The Japanese Ministry of Health, Labor and Welfare reports that frailty can lead to impairment of both mental and physical functioning. Chronic diseases such as diabetes and dementia may underlie frailty. It is important to prevent progression of frailty and extend the healthy lifespan. In herbal medicine practice, including Japanese Kampo medicine, "Mibyo," a presymptomatic state, has long been recognized and may be applicable to frailty. Kampo medicines may include several medicinal plants and are thought to have the potential to improve symptoms of frailty, such as loss of appetite and body weight, fatigue, and sarcopenia, as well as anxiety, depression, and cognitive decline. Ninjin'yoeito (Ren Shen Yang Ying Tang) is the most powerful Kampo medicine and has been widely applied to palliative care of cancer patients. This review includes recent anti-aging studies and describes the effects and mechanisms of Ninjin'yoeito (Ren Shen Yang Ying Tang) when used for frailty or to extend a healthy life expectancy.

Enhanced Oral Bioavailability of Chlormadinone Acetate through a Self-Microemulsifying Drug Delivery System for a Potential Dose Reduction

Chlormadinone acetate (CMA) is a derivative of the naturally secreted hormone progesterone and exhibits reliable contraceptive and non-contraceptive benefits. Although the marketed product of CMA as oral tablets under the trade name Belara® has been highly successful, there is still room for further improvements in oral bioavailability and a reduction in the clinical dose to decrease related adverse effects. In the current study, a CMA-based self-microemulsifying drug delivery system (SMEDDS) was developed using 32% ethyl oleate as an oil phase, 40% Tween-80 as a surfactant, and 12% Transcutol P combined with 16% PEG400 as a cosurfactant, resulting in spherical droplets with a z-average particle size of 38.92 nm and an average zeta potential of - 3.18 mv. The in vitro release rate of CMA from CMA-SMEDDS in different media (distilled water, HCl solution at pH 1.2, phosphate buffers at pH 4.5 and pH 6.8) was significantly faster than that from Belara® in the first 15 min. A pharmacokinetic study in rats showed that the C_max and AUC of CMA-SMEDDS were significantly higher (P < 0.01) than those of Belara®, with a 1.98-fold increase in oral bioavailability. In comparison with Belara®, the developed CMA-SMEDDS showed promising release profiles both in vitro and in vivo, which could potentially be useful in enhancing oral bioavailability and reducing the clinical dose of CMA.

Tadalafil for the Treatment of Lower Urinary Tract Symptoms in Japanese Men with Benign Prostatic Hyperplasia: Results from a 12-week Placebo-controlled Dose-finding Study with a 42-week Open-label Extension

OBJECTIVES

To examine the efficacy, safety, and dose response of tadalafil once daily in Japanese men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH-LUTS).

METHODS

Men ≥45 years with moderate-to-severe BPH-LUTS were randomized to once-daily placebo (N = 140), tadalafil 2.5 mg (N = 142), or tadalafil 5.0 mg (N = 140), in a 12-week double-blind phase, followed by a 42-week, tadalafil 5.0 mg open-label extension (OLE) phase (N = 394). The primary outcome was total International Prostate Symptom Score (IPSS) change from baseline to last available observation in the double-blind phase.

RESULTS

The least squares (LS) mean difference between placebo and tadalafil in total IPSS change from baseline was -0.7 (P = 0.201) and -1.1 (P = 0.062) for tadalafil 2.5 and 5 mg, respectively (ANCOVA; a dose-dependent improvement in placebo-adjusted total IPSS for tadalafil 5 mg versus 2.5 mg of 57%). Repeated-measures analyses identified a significant total IPSS change for tadalafil 5 mg (LS mean difference between placebo and tadalafil 5 mg: -1.2; P = 0.035), but not tadalafil 2.5 mg, at week 12. Significant improvements for tadalafil 5 mg were demonstrated (ANCOVA) for IPSS obstructive subscore (P = 0.033) and IPSS quality of life index (P = 0.022). Numerical improvements in IPSS scores were maintained over the OLE phase. Tadalafil was well tolerated with no unexpected adverse events.

CONCLUSION

Tadalafil (5.0 mg) had a favorable benefit-to-risk profile, supporting further investigation of tadalafil (5.0 mg) in Japanese men with BPH-LUTS.

Prostate cancer incidence among finasteride and alpha-blocker users in the Finnish Prostate Cancer Screening Trial

Background:

The Prostate Cancer Prevention Trial has shown a protective effect of finasteride on prostate cancer in low-risk men. It is uncertain whether similar results can be expected when finasteride is used to treat benign prostatic hyperplasia.

Methods:

We performed an observational cohort study within the Finnish Prostate Cancer Screening Trial. Using a comprehensive prescription database on medication reimbursements during 1995–2004 of men using finasteride or alpha-blockers for benign prostatic hyperplasia, we evaluated prostate cancer incidence among 23 320 men screened during 1996–2004.

Results:

Compared to medication non-users, overall prostate cancer incidence was not significantly affected in finasteride users (hazard ratio 0.87; 95% CI 0.63–1.19). Incidence of Gleason 2–6 tumours, however, was decreased among finasteride users (HR 0.59; 95% CI 0.38–0.91), whereas incidence of Gleason 7–10 tumours was unchanged (HR 1.33; 95% CI 0.77–2.30). The protective effect concerned mainly screen-detected tumours. Overall prostate cancer risk was not significantly reduced among alpha-blocker users relative to non-users, but decreased incidence of high-grade tumours was observed (0.55; 95% CI 0.31–0.96).

Conclusions:

The detection of low-grade, early-stage tumours is decreased among men who use finasteride for symptomatic BPH. The protective effect of finasteride can also be expected in men with benign prostatic hyperplasia.

Relevance of anti-reactive oxygen species activity to anti-inflammatory activity of components of eviprostat, a phytotherapeutic agent for benign prostatic hyperplasia

Inflammation is a common finding in benign prostatic hyperplasia (BPH). The phytotherapeutic agent eviprostat is a popular treatment for BPH in Japan and Germany. This agent consists of five components; four are extracted from Chimaphila umbellata, Populus tremula, Pulsatilla pratensis and Equisetum arvense (coded as EVI-1, EVI-2, EVI-3 and EVI-4, respectively) and the fifth is germ oil from Triticum aestivum (coded as EVI-5). In this study, the effects of each component on the reactive oxygen species (ROS), superoxide anion (O2-) and hydroxyl radical (OH*) generated in cell-free systems and human neutrophils, and on carrageenin-induced paw edema in rats were investigated. EVI-1, EVI-2 and EVI-4 suppressed the O2- levels in the xanthine/xanthine oxidase system, and EVI-1, EVI-2, EVI-3 and EVI-4 abolished the OH* produced in a Fenton-type reaction system, so that EVI-1, EVI-2 and EVI-4 possessed inhibitory action with respect to both O2- and OH*. EVI-1, EVI-2 and EVI-4 also reduced ROS levels in phorbol myristate acetate-stimulated neutrophils. The paw swelling was inhibited by a mixture of EVI-1, EVI-2, EVI-3, EVI-4 and EVI-5 (a mixture which is equivalent to eviprostat) or by a mixture of EVI-1, EVI-2 and EVI-4, even though each component alone did not significantly inhibit the swelling. These findings suggest that the suppression of ROS by EVI-1, EVI-2 and EVI-4 may partly contribute to the anti-inflammatory action of eviprostat, and this action may be implicated in its therapeutic effect on BPH.

Prostate cancer risk among users of finasteride and alpha-blockers - a population based case-control study

Finasteride has been reported to reduce prostate cancer risk in asymptomatic men. However, in clinical practice finasteride and alpha-blockers are used to treat benign prostatic hyperplasia (BPH). We evaluated prostate cancer risk among users of BPH pharmacotherapy at the population level. Comprehensive Finnish national registries provided information on 24723 prostate cancer cases and controls. Overall, prostate cancer risk was elevated among users of both drug categories compared to non-users (odds ratio, OR=1.41; 95% confidence interval, CI 1.31-1.51 for finasteride and OR=1.79; 95% CI 1.67-1.91 for alpha-blockers). However, the risk was lower among finasteride users when compared with alpha-blocker users (OR=0.80; 95% CI 0.64-1.00). Regular finasteride users had the lowest risk. The increased risk is probably due to enhanced diagnostics of prostate cancer in men with BPH. Finasteride use does not decrease prostate cancer incidence compared with non-users. Nevertheless, the risk is lower when compared with alpha-blocker users.