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Combination therapy with rofecoxib and finasteride in the treatment of men with lower urinary tract symptoms (LUTS) and benign prostatic hyperplasia (BPH).
PURPOSE: Cyclooxygenase-2 (COX-2) is expressed in human BPH tissue and displays either a pro-inflammatory effect or a proliferative effect on prostate cells. The aim of this study is to analyze whether combination therapy with rofecoxib, a COX-2 inhibitor, and finasteride offers an advantage compared to finasteride monotherapy in patients with BPH. MATERIALS AND METHODS: This is a single centre unblinded trial. Forty-six consecutive men with LUTS and BPH were entered into the study and were randomized to receive rofecoxib 25mg/day plus finasteride 5mg/day (group B) versus finasteride 5mg/day alone (group A) for 24 weeks. Inclusion criteria included also a prostate size greater than 40 cc. The efficacy and safety of treatments were assessed at baseline and at week 4, 12 and 24. RESULTS: In our population, both treatments (groups A and B) produced statistically significant improvements in total IPSS and Q(max) from baseline during follow-up, although they were very low in particular for the finasteride alone group at 4 weeks. We found that finasteride monotherapy produces very little improvement at the 1 month interval. In comparing group A with group B, a significantly higher improvement in IPSS (p=0.0001) and Q(max) (p=0.03) was obtained in group B at 4 weeks interval (% cases with IPSS reduction >4 points: group B=34.7, group A=0; % cases with Q(max) improvement >3 ml/s: group B=8.7, group A=0), whereas at week 24, the differences between the two treatments were not significant (p>0.05). CONCLUSIONS: In our population, the advantage of the combination therapy compared to finasteride alone is significant in a short-term interval (4 weeks). It can be hypothesized that the association of rofecoxib with finasteride induces a more rapid improvement in clinical results until the effect of finasteride becomes predominant.
Estimated impact of the Prostate Cancer Prevention Trial on population mortality.
BACKGROUND: The potential public health impact of the recently completed Prostate Cancer Prevention Trial (PCPT) is debated. The results indicated that the period prevalence of prostate cancer was reduced by 24.8% due to finasteride, whereas an increase in the rate of high-grade tumors (Gleason score 8-10) among men who were diagnosed with cancer also was found (5.0% in the PCPT placebo arm vs. 11.9% in the PCPT finasteride arm). Whether the increased Gleason score was valid or was a histologic artifact is under investigation. METHODS: The authors estimated the number of person-years saved assuming a 24.8% reduction in the incidence of prostate cancer for 5 years among United States males age >/= 55 years. Scenarios for different proportions of patients with high-grade Gleason scores also were considered. RESULTS: With a 24.8% reduction in the number of men with newly diagnosed prostate cancer, the authors estimated that 316,760 person-years would be saved due to finasteride in the United States. An absolute increase of 6.9% in the proportion of men with high-grade tumors in the United States cancer population (corresponding to the difference between the rates on the placebo and finasteride arms of the PCPT) would reduce the number of person-years saved to 262,567. For each absolute increase of 5% in the proportion of patients with high-grade tumors, the number of person-years saved would be reduced by approximately 39,000. CONCLUSIONS: The results of the PCPT may have a major impact on population mortality from prostate cancer if they are applied clinically. The potential detrimental effects of an increased rate of patients who have prostate cancer with high-grade Gleason scores would be outweighed by a reduction in incidence. Cancer 2005. (c) 2005 American Cancer Society.
Pharmacological effects of the lipidosterolic extract of Serenoa repens (Permixon) on rat prostate hyperplasia induced by hyperprolactinemia: comparison with finasteride.
BACKGROUND: The growth of the prostate gland is mainly dependent on androgens. Other hormones, like prolactin (PRL), also influence prostate development. Our purpose was to analyze and compare the effects of two drugs (alpha-reductase inhibitor) used in the therapy of benign prostatic hyperplasia: lipidosterolic extract of Serenoa repens (LSESR), and finasteride in an in vivo model of rat prostate hyperplasia induced by hyperprolactinemia. METHODS: Hyperprolactinemia was induced by 30 daily injections of sulpiride. Wistar rats received daily gavages of LSESR or finasteride. We used the following groups: control, castrated, castrated with a substitute testosterone (T), or alpha-dihydrotestosterone (DHT) implant. RESULTS: Hyperprolactinemia increases the wet weight and induces hyperplasia in the lateral prostate (LP). Unlike finasteride, LSESR significantly reduced LP growth and hyperplasia in castrated, DHT-implanted, and sulpiride-treated rats. CONCLUSIONS: Finasteride was only capable of inhibiting the effect of androgens on rat prostate enlargement. LSESR inhibited not only the androgenic but also the trophic effect of PRL in rat LP hyperplasia.
Structure-function studies of human 5-alpha reductase type 2 using site directed mutagenesis.
Site directed mutagenesis of human steroid alpha-reductase types 1 (5AR1) and 2 (5AR2) has been used to identify residues involved in inhibitor/substrate binding by 5AR2. Replacing residues 21-24 (GALA) in 5AR2 with the analogous residues 26-29 (AVFA) from 5AR1 did not significantly alter either the Km for testosterone or the Ki for the competitive inhibitor Finasteride. Replacement of AVFA in 5AR1 with GALA from 5AR2 however, significantly decreased the Km and increased the resistance to Finasteride. These findings confirm that 5AR1 residues 26-29 are involved in inhibitor/substrate binding but suggest residues 21-24 of 5AR2 are not. Replacing residues 20-29 (QCAVGCAVFA) of 5AR1 with the analogous residues 15-24 (ATLVALGALA) from 5AR2, changed the Km and Ki to values approaching those for wild type 5AR2. Replacing residues VAL in wild type 5AR2 with VGC from 5AR1 did not change Km or Ki but replacing ATL in 5AR2 with QCA from 5AR1 significantly decreased the Km and increased the resistance to Finasteride. Conversely, replacing QCA with ATL in 5AR1 containing GALA in place of AVFA, increased the Km and decreased resistance to Finasteride. These findings indicate residues 15-17 of human 5AR2 participate in inhibitor/substrate binding whereas residues 18-20 do not.
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