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PubMed1998

A novel in vitro model to screen steroid 5 alpha-reductase inhibitors against benign prostatic hyperplasia.

A convenient and rapid in vitro model to screen steroid 5 alpha-reductase inhibitors, which are effective in the treatment of benign prostatic hyperplasia (BPH), was developed. In the presence of nicotinamide adenine dinucleotide phosphate (NADPH), steroid 5 alpha-reductase converts testosterone to dihydrotestosterone (DHT) which is a major etiologic factor of BPH. NADPH has characteristic absorbance at 340 nm, and the absorbance spectrum may be used to identify NADPH as a kind of the substrate in this enzymatic reaction. In this paper, NADPH, steroid 5 alpha-reductase, series concentration of testosterone and finasteride, and 4 ml Tris-HCl buffer were continuously incubated together at 37 degrees C and the NADPH OD values were continually measured. The descending rate of NADPH OD340nm value by linear regression from the beginning to the 10th minute is close to the initial velocity of the enzymatic reaction. The precise activity of the steroid 5 alpha-reductase was the slope after subtracting that of the blank control. The inhibition constant (Ki) of steroid 5 alpha-reductase inhibitors could be calculated according to the Lineweaver-Burk plots. Two drug screening models, the most common isotope model and the novel model, were compared in this paper. The result showed that the latter one is more economical, quicker and more effective than the former one.

5-alpha Reductase Inhibitors↗
PubMed1998

Effects of some novel inhibitors of C17,20-lyase and 5alpha-reductase in vitro and in vivo and their potential role in the treatment of prostate cancer.

The effects of some novel steroidal compounds were evaluated against both human C17,20-lyase and 5alpha-reductase in vitro and also against androgen synthesis in normal male rats. L-2, L-36, L-37, and I-41 showed potent inhibition of human testicular C17,20-lyase, with IC50s of 43, 39, 42, and 58 nM, respectively. In contrast, ketoconazole, a competitive inhibitor of C17,20-lyase, had an IC50 of 76 n.M. L-36 also showed potent inhibitory activity against 5a-reductase in human prostatic microsomes, with an IC50 of approximately 31 nM. The inhibitory activities of L-2 and 1-41 on 5alpha-reductase were moderate, with IC50s of 75 and 151 nM, respectively, whereas L-37 showed little inhibitory activity against this enzyme. In comparison, finasteride, a potent inhibitor of 5alpha-reductase, had an IC50 of 33 nM. When normal male rats were treated with these novel compounds (50 or 100 mg/kg/day) for 14 consecutive days, the wet weight of the prostate was significantly reduced by L-36, L-37, and I-41, compared to the control group. Testosterone levels in rat serum were also reduced by L-36 (55%), L-37 (86%), and I-41 (53%). The concentrations of testosterone in rat testes were reduced by these novel compounds by 13-74%. The compounds also reduced the concentration of testosterone in rat prostates by 35-75%. Similarly, dihydrotestosterone (DHT) concentration in rat serum was reduced 30-89% by these compounds, compared to the control group. Prostatic DHT levels were also lower in rats treated with L-36 (48%), L-37 (54%), or I-41 (26%). In contrast, L-2 enhanced serum testosterone and prostatic DHT concentrations by >50%. These findings suggest that the dual activities of several of these novel inhibitors of C17,20-lyase and 5alpha-reductase accounts for the diminished levels of circulating androgens in vivo.

Androgens↗
PubMedDate not supplied

[Uroselectivity of alpha-1 antagonism in the treatment of benign prostatic hypertrophy: on the pharmacologic concept of the clinical approach].

Benign prostatic hyperplasia is the most common cause of voiding dysfunction in men. It becomes symptomatic from the fifth decade of life and needs treatment in 50 per cent of patients. Hyperplastic prostatic tissue and the smooth involuntary sphincter have a high density of alpha 1-adrenoceptors, thus alpha 1-blockers can decrease sphincter tone and reduce the tension exerted by the prostatic muscular component. Attempts have been made to find alpha 1-antagonists that have a selective effect on the prostate (alfuzosin), are long acting (tamsulosin, terazosin, doxazosin) or present specificity on the alpha 1A prostatic adrenoceptors (tamsulosin), in order to maintain efficacy without affecting blood pressure. Finasteride, a 5 alpha-reductase inhibitor without hypotensive side-effect may be more effective in men with a predominantly glandular component to their benign hyperplasia or with very large prostate glands, but has a longer onset of action and produces more adverse sexual effects. Thus, alpha-1 antagonists can be considered as an appropriate treatment option in patients with troublesome symptoms of BPH and who have not developed serious complications indicating surgery.

Adrenergic alpha-1 Receptor Antagonists↗
PubMed1998

Effects of long-term treatment with Serenoa repens (Permixon) on the concentrations and regional distribution of androgens and epidermal growth factor in benign prostatic hyperplasia.

BACKGROUND: The n-hexane lipido-sterol extract of Serenoa repens (LSESr, Permixon, Pierre Fabre Medicament, Castres, France), a phytotherapeutic agent used in the treatment of benign prostatic hyperplasia (BPH), has a multisite mechanism of action including inhibition of types 1 and 2 5alpha-reductase and competitive binding to androgen receptors in prostatic cells. Here, the response of testosterone (T), dihydrotestosterone (DHT), and epidermal growth factor (EGF) in BPH tissue of patients treated with LSESr (320 mg/day for 3 months) is analyzed. METHODS: BPH samples were sectioned in periurethral, subcapsular, and intermediate regions: in each region T, DHT, and EGF were determined by radioimmunoassay after purification on celite columns or Sep-pak C18 cartridges. RESULTS: In the untreated group, T, DHT, and EGF presented the highest concentrations in the periurethral region (615 +/- 62 (SE) pg/g tissue, 7,317 +/- 551 pg/g tissue, and 20.9 +/- 3.3 ng/g tissue, respectively) with respect to the peripheral subcapsular region (425 +/- 45 pg/g tissue, 4,215 +/- 561 pg/g tissue, and 10.8 +/- 1.4 ng/g tissue, respectively). In the LSESr-treated group, a statistically significant reduction was observed, mainly in the periurethral region of DHT (2,363 +/- 553 pg/g tissue, P < 0.001) and EGF (6.98 +/- 2.48 ng/g tissue, P < 0.01), with increased T values (1,023 +/- 101 pg/g tissue, P < 0.001). CONCLUSIONS: The decrease of DHT and the rise of T in BPH tissue of patients treated with Permixon confirms the capacity of this drug to inhibit in vivo 5alpha-reductase in human pathological prostate. A marked decrease of EGF, associated with DHT reduction, was also observed. These biochemical effects, similar to those obtained with finasteride, are particularly evident in the periurethral region, whose enlargement is responsible for urinary obstruction, with respect to the subcapsular region. A possible speculation is that the preferential reduction of DHT and EGF content in the periurethral region is involved in the clinical improvement of the obstructive symptoms in BPH during LSESr therapy.

Aged↗
PubMed1998

5alpha-reductase and 17beta-hydroxysteroid dehydrogenase expression in epithelial cells from hyperplastic and malignant human prostate.

The aim of this study on testosterone (T) metabolism in benign prostatic hyperplasia (BPH) and prostatic cancer was to compare the formation of metabolites in freshly isolated epithelial cells and in cells of long-term cultures (2 passages) and to identify the 5alpha-reductase (5alpha-R) and 17beta-hydroxysteroid dehydrogenase (17beta-HSD) isoforms responsible for metabolite formation. Androst-4-enedione (A), dihydrotestosterone (DHT) and 5alpha-androstanedione (5alpha-A) formation were measured by high-performance liquid chromatography coupled to a Flo-one HP radioactivity detector. Enzyme isoforms were studied by Northern blot analysis and reverse transcriptase-polymerase chain reaction (RT-PCR). T conversion into A by 17beta-HSD, rather than reduction into DHT by 5alpha-R, was by far the predominant activity in cultured epithelial cells. The metabolic profile did not differ substantially between BPH and cancer cells. Long-term cell culture led to an increase in A formation compared with the level recorded in freshly isolated cells, with no significant incidence on the relative DHT level. According to RT-PCR results, both 5alpha-R isoforms (1 and 2) and 2 17beta-HSD isoforms (2 and 3) are present in epithelial cell cultures and in tissues. According to Northern blot analyses, the mRNAs for 5alpha-R2 and 17beta-HSD4 are expressed in tissue and those for 5alpha-R1 and types 2 and 4 17beta-HSD in isolated cell cultures. Moreover, finasteride, a specific 5alpha-R2 inhibitor, inhibits DHT and 5alpha-A formation in long-term cell culture of adenocarcinoma epithelial cells plated on Matrigel, suggesting a 5alpha-R2 expression. Thus, although 5alpha-R2 is present in freshly isolated epithelial cell cultures and in long-term epithelial cells cultured on Matrigel and predominates in prostate tissue, it is the 5alpha-R1 isoform that is preferentially expressed in epithelial cell cultures.

17-Hydroxysteroid Dehydrogenases↗
PubMed1999

Neural androgen receptor regulation: effects of androgen and antiandrogen.

Androgens exert profound effects on the organization and function of the central nervous system. These effects are mediated by the androgen receptor (AR), a ligand-dependent transcription factor. The mechanisms of AR regulation in neural tissue, however, remain to be fully elucidated. Characterizing this process can provide important information regarding receptor function and AR gene regulation in the brain. Previously, it was shown that testosterone (T) up-regulated neural AR in a dose-dependent manner in both male and female mice. In the present study, whether AR was differentially regulated by the natural agonists T and dihydrotestosterone (DHT) or the nonsteroidal antagonist flutamide (FLU) was assessed. Males were gonadectomized and AR levels were allowed to decline to baseline 3 days after surgery. Changes in AR protein content produced by the various treatments were measured by semiquantitative Western blot of limbic system extracts. Treatment with T or DHT significantly augmented AR 3 and 7 h after hormone administration, but only DHT sustained this increase for 21 h. This difference also was observed when males were given T plus finasteride (FIN, a 5alpha reductase inhibitor). The findings demonstrate that the two endogenous ligands have differential time course effects on neural AR. The antiandrogen FLU failed to up-regulate AR at doses up to 100 times higher than T or DHT. When administered concomitantly with T or DHT, it effectively inhibited the augmentation of AR normally seen 3 h after androgen treatment. While immunohistochemical studies showed that FLU was able to promote nuclear translocation of AR, Western analysis revealed that FLU, in contrast to T and DHT, failed to maintain the integrity of AR. The results demonstrate that (a) the endogenous androgens T and DHT regulate AR differently, suggesting a potential cellular mechanism that may contribute to the difference in neural target gene sensitivity to these androgens; (b) up-regulation of AR occurs only in the presence of agonists; (c) the mechanism of action of FLU in the brain involves inhibition of AR protein up-regulation normally seen in response to androgen; and (d) FLU promotes AR nuclear translocation but not augmentation of cellular AR populations. These findings demonstrate that in vivo AR regulation in the brain basically parallels mechanisms proposed from results obtained with transfected cells and cell lines.

Androgen Antagonists↗
PubMed2003

Cyproterone acetate for hirsutism.

BACKGROUND: Hirsutism is a distressing and relatively common endocrine problem in women which may prove difficult to manage. Cyproterone acetate, an anti-androgen, is frequently used to treat hirsutism, usually in combination with ethinyl estradiol. OBJECTIVES: The objective of this review was to investigate the effectiveness of cyproterone acetate alone, or in combination with ethinyl estradiol, in reducing hair growth in women with hirsutism secondary to ovarian hyperandrogenism. SEARCH STRATEGY: The Cochrane Menstrual Disorders and Subfertility Group trials register was searched (last search - 4 June 2002). The Cochrane Menstrual Disorders and Subfertility Group register is based on regular searches of MEDLINE (1966 to 2002), EMBASE (1980 to 2002), CINAHL (1982 to 2002), PsycINFO (1987 to 2002) and CENTRAL (Issue 2, 2002 of the Cochrane Library) the handsearching of several journals and conference proceedings, and searches of several key grey literature sources. All publications of randomised controlled trials of cyproterone acetate with or without estrogen versus placebo or other drug therapies for hirsutism were identified. SELECTION CRITERIA: All randomised controlled studies comparing:- cyproterone acetate to placebo- cyproterone acetate with ethinyl estradiol to placebo- cyproterone acetate with ethinyl estradiol to cyproterone acetate alone- cyproterone acetate (with or without estradiol) to other medical therapies for treatment of hirsutism. DATA COLLECTION AND ANALYSIS: Eleven studies were identified which fulfilled the inclusion criteria. Nine randomised studies were included in the review, and two were excluded because of insufficient information. Only one study had more than 100 women included in the analysis. The major outcomes included: subjective improvement in hirsutism, changes in Ferriman Gallwey scores, changes in linear hair growth and hair shaft diameter, alterations in endocrine parameters, side effects to treatment, withdrawals during therapy MAIN RESULTS: There were no clinical trials comparing cyproterone acetate alone with placebo. There was one small study comparing cyproterone acetate in combination with ethinyl estradiol to placebo. In this study there was a significant subjective reduction in hair growth with cyproterone acetate therapy, although the confidence limits were large. There were no studies comparing cyproterone acetate alone with cyproterone acetate in combination with ethinyl estradiol to treat hirsutism. In studies where cyproterone acetate was compared to other drug modalities (ketoconazole, spironolactone, flutamide, finasteride, GnRH analogues) no difference in clinical outcome was noted. There were, however, endocrinological differences in androgen and estrogen levels between different drug therapies. There were insufficient data to assess differences in side effects between women treated with cyproterone acetate and other medical therapy. REVIEWER'S CONCLUSIONS: Cyproterone acetate combined with estradiol results in a subjective improvement in hirsutism compared to placebo. Clinical differences in outcome between cyproterone acetate and other medical therapies were not demonstrated in the studies included in this review. This may be because of the small size of the studies, lack of standardized assessment and lack of objective determinants of improvement in hirsutism. The endocrinological effects of the different drug therapies reflect the mode of action. Larger carefully designed studies are needed to compare efficacy and safety profiles between drug therapies for hirsutism.

Androgen Antagonists↗
PubMed2000

5 alpha-reductase in intact DU145 cells: evidence for isozyme I and evaluation of novel inhibitors.

The epithelial-like human prostatic carcinoma cell line DU145, which expresses 5 alpha-reductase type I isozyme, was used to test a series of potential 5 alpha-reductase inhibitors. The exclusive expression of the type I isozyme was confirmed by PCR and subsequent DNA sequence analysis. Culture conditions were optimized for high conversion rates. Using this whole cell assay finasteride, 4MA, and 65 steroidal and non-steroidal compounds synthesized in our group were tested for their inhibitory activity. Inhibitors with IC50 values in the nanomolar range could be identified.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2004

Tailoring cancer chemoprevention regimens to the individual.

The present article, which is a tribute to the memory of Dr. Edward Bresnick, emphasizes the importance of environmental and life-style factors for cancer causation in the human population and points out approaches to cancer prevention. These approaches include vaccinations for the prevention of cancers that are caused by infectious agents as well as the use of cancer chemopreventive agents. The use of tamoxifen and letrozole to prevent breast cancer, finasteride to prevent prostate cancer, sunscreens or topical applications of 5-fluorouracil to prevent sunlight-induced skin cancer, and aspirin or calcium to prevent colon cancer are a few examples of cancer chemoprevention in high risk individuals and in the general population. An underdeveloped area of cancer chemoprevention is the use of combinations of agents that work by different mechanisms. It was pointed out that animal studies indicate that many cancer chemopreventive agents inhibit carcinogenesis under one set of experimental conditions but enhance carcinogenesis under another set of experimental conditions. These observations suggest that tailoring the chemopreventive regimen to the individual or to groups of individuals living under different environmental conditions or with different mechanisms of carcinogenesis may be an important aspect of cancer chemoprevention in human populations. How to tailor cancer chemoprevention regimens to the individual is an important challenge for the future.

Animals↗
PubMed2005

Sexual dimorphism of growth plate prehypertrophic and hypertrophic chondrocytes in response to testosterone requires metabolism to dihydrotestosterone (DHT) by steroid 5-alpha reductase type 1.

Rat costochondral growth plate chondrocytes exhibit sex-specific and cell maturation dependent responses to testosterone. Only male cells respond to testosterone, although testosterone receptors are present in both male and female cells, suggesting other mechanisms are involved. We examined the hypothesis that the sex-specific response of rat costochondral cartilage cells to testosterone requires further metabolism of the hormone to dihydrotestosterone (DHT). Resting zone (RC) and growth zone (GC, prehypertrophic and upper hypertrophic zones) chondrocytes from male and female Sabra strain rats exhibited sex-specific responses to testosterone and DHT: only male cells were responsive. Testosterone and DHT treatment for 24 h caused a comparable dose-dependent increase in [3H]-thymidine incorporation in quiescent preconfluent cultures of male GC cells, and a comparable increase in alkaline phosphatase specific activity in confluent cultures. RC cells responded in a differential manner to testosterone and DHT. Testosterone decreased DNA synthesis in male RC cells but DHT had no effect and alkaline phosphatase specific activity of male RC cells was unaffected by either hormone. Inhibition of steroid 5alpha-reductase activity with finasteride (1, 5, or 10 microg/ml), reduced the response of male GC cells to testosterone in a dose-dependent manner, indicating that metabolism to DHT was required. RT-PCR showed that both male and female cells expressed mRNAs for steroid 5alpha-reductase type 1 but lacked mRNAs for the type 2 form of the enzyme. Male cells also exhibited 5alpha-reductase activity but activity of this enzyme was undetectable in female cells. These observations show that sex-specific responses of rat growth zone chondrocytes to testosterone requires the further metabolism of the hormone to DHT and that the effect of DHT in the male growth plate is maturation-state dependent. Failure of female chondrocytes to respond to testosterone may reflect differences in testosterone metabolism, since these cells possess greater ability to aromatize the hormone to estradiol.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1996

New agents for cancer chemoprevention.

Clinical chemoprevention trials of more than 30 agents and agent combinations are now in progress or being planned. The most advanced agents are well known and are in large Phase III chemoprevention intervention trials or epidemiological studies. These drugs include several retinoids [e.g., retinol, retinyl palmitate, all-trans-retinoic acid, and 13-cis-retinoic acid], calcium, Beta carotene, vitamin E, tamoxifen, and finasteride. Other newer agents are currently being evaluated in or being considered for Phase II and early Phase III chemoprevention trials. Prominent in this group are all-trans-N-(4-hydroxy phenyl)retinamide (4-HPR) (alone and in combination with tamoxifen), 2-difluoromethylornithine (DFMO), nonsteroidal antiinflammatory drugs (aspirin, piroxicam, sulindac), oltipraz, and dehydroepiandrostenedione (DHEA). A third group is new agents showing chemopreventive activity in animal models, epidemiological studies, or in pilot clinical intervention studies. They are now in preclinical toxicology testing or Phase I safety and pharmacokinetics trials preparatory to chemoprevention efficacy trials. These agents include S-allyl-l-cysteine, curcumin, DHEA analog 8354 (fluasterone), genistein, ibuprofen, indole-3-carbinol, perillyl alcohol, phenethyl isothiocyanate, 9-cis-retinoic acid, sulindac sulfone, tea extracts, ursodiol, vitamin D analogs, and p-xylyl selenocyanate. A new generation of agents and agent combinations will soon enter clinical chemoprevention studies based primarily on promising chemopreventive activity in animal models and in mechanistic studies. Among these agents are more efficacious analogs of known chemopreventive drugs including novel carotenoids (e.g., alpha-carotene and lutein). Also included are safer analogs which retain the chemopreventive efficacy of the parent drug such as vitamin D3 analogs. Other agents of high interest are aromatase inhibitors (e.g., (+)-vorozole), and protease inhibitors (e.g., Bowman-Birk soybean trypsin inhibitor). Combinations are also being considered, such as vitamin E with l-selenomethionine. Analysis of signal transduction pathways is beginning to yield classes of potentially active and selective chemopreventive drugs. Examples are ras isoprenylation and epidermal growth factor receptor inhibitors.

Animals↗
PubMed2006

Reduced metabolites mediate neuroprotective effects of progesterone in the adult rat hippocampus. The synthetic progestin medroxyprogesterone acetate (Provera) is not neuroprotective.

The ovarian hormone progesterone is neuroprotective in different experimental models of neurodegeneration. In the nervous system, progesterone is metabolized to 5alpha-dihydroprogesterone (DHP) by the enzyme 5alpha-reductase. DHP is subsequently reduced to 3alpha,5alpha-tetrahydroprogesterone (THP) by a reversible reaction catalyzed by the enzyme 3alpha-hydroxysteroid dehydrogenase. In this study we have analyzed whether progesterone metabolism is involved in the neuroprotective effect of the hormone in the hilus of the hippocampus of ovariectomized rats injected with kainic acid, an experimental model of excitotoxic cell death. Progesterone increased the levels of DHP and THP in plasma and hippocampus and prevented kainic-acid-induced neuronal loss. In contrast to progesterone, the synthetic progestin medroxyprogesterone acetate (MPA, Provera) did not increase DHP and THP levels and did not prevent kainic-acid-induced neuronal loss. The administration of the 5alpha-reductase inhibitor finasteride prevented the increase in the levels of DHP and THP in plasma and hippocampus as a result of progesterone administration and abolished the neuroprotective effect of progesterone. Both DHP and THP were neuroprotective against kainic acid. However, the administration of indomethacin, a 3alpha-hydroxysteroid dehydrogenase inhibitor, blocked the neuroprotective effect of both DHP and THP, suggesting that both metabolites are necessary for the neuroprotective effect of progesterone. In conclusion, our findings indicate that progesterone is neuroprotective against kainic acid excitotoxicity in vivo while the synthetic progestin MPA is not and suggest that progesterone metabolism to its reduced derivatives DHP and THP is necessary for the neuroprotective effect of the hormone.

3-Hydroxysteroid Dehydrogenases↗
PubMed2004

Effect of permixon on human prostate cell growth: lack of apoptotic action.

BACKGROUND: Permixon, a phytotherapeutic agent derived from the saw palmetto or Serenoa repens plant, is a lipid/sterol extract that is believed to interfere with 5alpha-reductase activity, thus inhibiting prostate growth. In this study, we investigated the magnitude and specificity of the effect of Permixon on cell proliferation and apoptosis in human prostate cancer cells. METHODS: The effect of Permixon was examined in androgen-independent PC-3 prostate cancer cells, androgen-sensitive LNCaP prostate cancer cells, and MCF-7 breast cancer cells in vitro. Cell growth, apoptosis induction, and cell proliferation was studied after exposure to Permixon at two concentrations (10 and 100 microg/ml). Cell proliferation and cell cycle progression were determined after 24 hr on the basis of (3)[H]-thymidine incorporation assay and flowcytometric analysis, respectively. Apoptosis induction was evaluated in treated and untreated cultures using the Hoescht staining and caspase-3 activation. RESULTS: Exposure of prostate and breast cancer cells to a high dose of Permixon (100 microg/ml) resulted in a significant decrease in the rate of cell growth; an effect that was not time-dependent and was not associated with cell cycle arrest. Permixon treatment (at either high or low dose) had no effect on apoptosis induction in prostate cancer cell lines (P > 0.6). Furthermore, in vitro Permixon was a weak inhibitor of 5alpha-reductase activity type 2 in prostatic homogenates. CONCLUSIONS: The results indicate the ability of Permixon to affect prostate cancer cell growth without inducing apoptosis or cell cycle arrest. This effect was not prostate-specific and was only manifested at high concentrations of Permixon. Furthermore our findings indicate that Permixon is weak inhibitor of 5alpha-reductase compared to finasteride. This study challenges previous evidence on the anti-growth effect of Permixon in the prostate and its ability to inhibit 5alpha-reductase activity, while questioning apoptosis as a mechanism of action of this phytotherapeutic against prostate growth, a concept that may have therapeutic significance.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2005

Differential alterations in 5alpha-reductase type 1 and type 2 levels during development and progression of prostate cancer.

BACKGROUND: In the prostate, conversion of testosterone to dihydrotestosterone (DHT), by the enzymes 5alpha-reductase types 1 and 2 (5alphaR1, 5alphaR2) is required for normal growth and probably also for development of prostate cancer (PCa). Finasteride, a 5alphaR2 inhibitor, was shown to reduce the prevalence of PCa in the Prostate Cancer Prevention Trial. However, inhibition of both 5alphaR isoenzymes causes a greater decrease in serum DHT. The aim of this study was to assess differential expression of these enzymes at various stages of PCa development. METHODS: Immunostaining for 5alphaR1 and 5alphaR2, using specific, well-validated antibodies, was evaluated in 26 benign prostatic hyperplasia (BPH) (16 for 5alphaR2), 53 primary PCa (21 for 5alphaR2), 18 prostatic intraepithelial neoplasia (PIN), 12 primary PCa treated with neoadjuvant androgen ablation, 15 locally recurrent PCa specimens, and 18 PCa metastases. RESULTS: The mean area of moderate plus high intensity staining for 5alphaR1 increased from 4.8 +/- 2.8% of total epithelial area in BPH, to 18.9 +/- 5.7% in PIN, 17.0 +/- 3.2% in primary cancer, 38.0 +/- 7.3% in recurrent cancer, and 55.8 +/- 8.5% in PCa metastases. The mean staining area for 5alphaR2 decreased from 58.8 +/- 7.2% in BPH, to 21.1 +/- 5.5% in PIN and 34.8 +/- 6.7% in primary PCa. Staining for 5alphaR2 was increased in recurrent cancer and PCa metastases compared to primary PCa, at 58.7 +/- 5.2% and 69.2 +/- 8.7%, respectively. CONCLUSIONS: 5alphaR1 immunostaining is increased and 5alphaR2 immunostaining is decreased during development of PCa. In addition, there is increased expression of both 5alphaR isozymes in recurrent and metastatic cancers, suggesting that both isozymes may be important in the development and progression of PCa.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1992

Validation of a symptoms questionnaire for benign prostatic hyperplasia.

We developed a questionnaire to assess the effect of finasteride on symptoms of benign prostatic hyperplasia (BPH) by modifying that of Boyarsky (1977). To validate the questionnaire, a cohort study was conducted in 2 groups of patients with BPH and 3 control groups without BPH. The BPH groups were: (1) 34 patients before TURP (transurethral resection of the prostate), average age 68 years; (2) 65 patients after TURP, average age 68 years; (3) 40 patients after other nonserious nonurological surgery, average age 50 years; (4) 14 healthy non-BPH volunteers, average age 58 years; and (5) 73 healthy non-BPH volunteers, average age 37 years. The questionnaire was administered once to all subjects, and a subset responded to a second administration. Mean total symptoms scores (TSS) from the initial questioning were 6.4, 3.2, 2.9, 2.6, and 1.6 for the 5 groups, respectively (pooled SD = 3.3); mean total troublesome symptoms scores (TTSS) were 4.8, 2.1, 1.4, 1.1, and 0.6, respectively (pooled SD = 2.2). All other groups were significantly less symptomatic and troubled than the pre-TURP group, and all surgical groups were significantly more so than the younger volunteer group. These data demonstrate the discriminant validity of the questionnaire. Corroborating prior data [Gregg et al., 1990], responsiveness was shown by the 3.7-point mean TSS improvement in response to TURP, which was significantly different from the near-zero changes in the other groups. Reproducibility was shown by kappa statistics being nearly all greater than 0.75 and an intraclass correlation coefficient of 0.64; construct validity and reliability were demonstrated by correlation (r = 0.7) with a general urination problems question; and internal consistency was documented by Cronbach's alpha values of approximately 0.6. We conclude that this questionnaire is a useful and validated tool for assessing BPH symptoms.

Evaluation Studies as Topic↗
PubMed2006

A fast liquid chromatographic/mass spectrometric screening method for the simultaneous detection of synthetic glucocorticoids, some stimulants, anti-oestrogen drugs and synthetic anabolic steroids.

A fast liquid chromatographic/mass spectrometric (LC/MS/MS) screening method for the detection, in urine, of synthetic glucocorticoids, stimulants (formoterol, modafinil and mesocarb), anti-oestrogens (finasteride, exemestane, anastrozole, letrozole and formestane) and synthetic anabolic steroids (stanozolol, gestrinone and tetrahydrogestrinone) is described. All these drugs (and/or their urinary metabolites) can be simultaneously extracted by a single liquid/liquid extraction step, at alkaline pH, after enzymatic hydrolysis with beta-glucuronidase, and assayed in 7 min by LC/MS/MS using electrospray ionization in positive ion mode and multiple reaction monitoring as the acquisition mode. All compounds show good reproducibility of both the retention times (CV% <2%) and the relative abundances (CV% <10%). The limits of detection for the anti-oestrogens, glucocorticoids and steroids are in the range of 1-30 ng/mL, and for the stimulants are in the range of 100-200 ng/mL, thus satisfying the minimum required performance limits of the World Anti-Doping Agency.

Anabolic Agents↗
PubMed2002

Concept evaluation: an assay for receptor-mediated and biochemical antiestrogens using pubertal rats.

At present, assessment of chemicals for receptor-mediated antiestrogenic activity involves inhibition of uterine growth stimulated by coadministration of a reference estrogen in either ovariectomized or immature rodents. In the present paper, we describe an alternative assay for both receptor-mediated and biochemical antiestrogens. The assay involves treatment of immature rats from postnatal (pnd) 25 or 26 for either 7 or 14 days and monitors two benchmarks of puberty, the mean day of vaginal opening and the weight of the uterus, that require estrogen activity. The receptor-mediated antiestrogens ZM 189,154 and Faslodex (ICI 182,780), the aromatase inhibitor Arimidex (Anastrozole), and the GnRH inhibitor Antarelix were each effective in preventing uterine growth and in delaying vaginal opening for the course of the experiments. The 5alpha-reductase inhibitor Finasteride was inactive in the assay indicating assay specificity for antiestrogens. Delays in uterine growth were clearly evident in the 7-day experiments, but assessment of vaginal opening required the 14-day protocol. No significant changes in body weight were observed in any of the experiments. It is concluded that the assay holds promise as a simple method of detecting antiestrogens and that it is worthy of further study.

Administration, Oral↗
PubMed1998

An ongoing validation of a Tier I screening battery for detecting endocrine-active compounds (EACs).

After previously examining an estrogen receptor agonist (17beta-estradiol), several additional compounds have been evaluated in a Tier I screening battery for detecting endocrine-active compounds (EACs): an estrogen receptor antagonist (ICI-182,780, ICI), an androgen receptor antagonist (flutamide, FLUT), a testosterone biosynthesis inhibitor (ketoconazole, KETO), a 5alpha-reductase inhibitor (finasteride, FIN), and an aromatase inhibitor (anastrozole, ANA). The Tier I battery incorporates two short-term in vivo tests (a 5-day ovariectomized female battery and a 15-day intact male battery) and an in vitro yeast transactivation system (YTS). The Tier I battery is designed to identify compounds that have the potential to act as agonists or antagonists to the estrogen, androgen, progesterone, or dopamine receptors, steroid biosynthesis inhibitors (aromatase, 5alpha-reductase, and testosterone biosynthesis), or compounds that alter thyroid function. ICI administration decreased uterine estrogen and progesterone receptor number in the female battery, increased serum follicle-stimulating hormone (FSH) levels and caused spermatid retention in the male battery, and activated gene transcription in the YTS containing the estrogen receptor. FLUT administration increased uterine stromal cell proliferation in the female battery and decreased weights for all androgen-dependent tissues, induced Leydig cell hyperplasia, and caused hormonal alterations (increased testosterone (T), estradiol (E2), dihydrotestosterone (DHT), luteinizing hormone (LH), and FSH) in the male battery, and competed for binding to the androgen receptor in the YTS competition assay. In the male battery KETO decreased weights for all androgen-dependent tissues, caused hormonal alterations (decreased T and DHT and increased LH and FSH), and induced spermatid retention. FIN decreased seminal vesicle and accessory sex gland (ASG) unit weight and caused hormonal alterations (decreased DHT and increased LH, and PRL) in the male battery. KETO was judged not to affect any of the endpoints in the female battery. ANA decreased ASG unit weight and serum E2 levels in the male battery. Using the responses obtained for all the endpoints in the Tier I battery, a distinct "fingerprint" was produced for each type of endocrine activity against which compounds with unknown activity can be compared. These data demonstrate that the described Tier I battery is useful for identifying EACs.

Animals↗