Inhibition of rat prostate carcinogenesis by a 5alpha-reductase inhibitor, FK143

Chemoprevention of Prostate Carcinogenesis by DFMO and/or Finasteride Treatment in Male Wistar Rats

In the present study the chemopreventive activities of DFMO, the irreversible inhibitor of ornithine decarboxylase, and finasteride, the inhibitor of prostatic 5a-reductase, against the development of chemically induced prostate adenocarcinoma by methylnitrosourea/testosterone propionate in male Wistar rats were investigated. According to histological examination, oral administration of DFMO and finasteride, either alone or combined, for two months to MNU/TP-inoculated rats reduced the tumor incidence to 11.11%, 10% and 10%, respectively, compared to tumored controls (64.3%). DFMO and/or finasteride treatment resulted in significant reductions in the wet weight of the prostate gland and seminal vesicles and its ratio relative to the total body weight, as well as the levels of prostate total protein, DNA, RNA and DNA/RNA ratio, compared to tumored controls. However, the effect of the combined treatment was of no statistical significance compared to single DFMO or finasteride treatment, as demonstrated by the non-significant differences between the mean values of most of the studied parameters. The tumor chemopreventive activity and the prostate growth inhibitory effect of DFMO and finasteride were due to suppression of prostate polyamine synthesis. ANOVA test revealed that the relative weight of the prostate as well as blood and tissue polyamine levels could be used as significant endpoint biomarkers for DFMO and finasteride as cancer chemopreventive agents.

A unifying biology of sex steroid-induced apoptosis in prostate and breast cancers

Prostate and breast cancer are the two cancers with the highest incidence in men and women, respectively. Here, we focus on the known biology of acquired resistance to antihormone therapy of prostate and breast cancer and compare laboratory and clinical similarities in the evolution of the disease. Laboratory studies and clinical observations in prostate and breast cancer demonstrate that cell selection pathways occur during acquired resistance to antihormonal therapy. Following sex steroid deprivation, both prostate and breast cancer models show an initial increased acquired sensitivity to the growth potential of sex steroids. Subsequently, prostate and breast cancer cells either become dependent upon the antihormone treatment or grow spontaneously in the absence of hormones. Paradoxically, the physiologic sex steroids now kill a proportion of selected, but vulnerable, resistant tumor cells. The sex steroid receptor complex triggers apoptosis. We draw parallels between acquired resistance in prostate and breast cancer to sex steroid deprivation. Clinical observations and patient trials confirm the veracity of the laboratory studies. We consider therapeutic strategies to increase response rates in clinical trials of metastatic disease that can subsequently be applied as a preemptive salvage adjuvant therapy. The goal of future advances is to enhance response rates and deploy a safe strategy earlier in the treatment plan to save lives. The introduction of a simple evidence-based enhanced adjuvant therapy as a global healthcare strategy has the potential to control recurrence, reduce hospitalization, reduce healthcare costs and maintain a healthier population that contributes to society.

Flaxseed suppressed prostatic epithelial proliferation in a rat model of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH), a disease occurring frequently among elderly males, is a slow progressive enlargement of the fibromuscular and epithelial structures of the prostate gland. Dietary factors may influence the prostate and exert an influence on prostatic growth and disease. The current study was undertaken to investigate the protective effect of dietary flaxseed supplementation against testosterone-induced prostatic hyperplasia in male rats. Forty male Wistar rats were divided into 5 groups: (1) untreated control; (2) treatment with testosterone propionate (TP) to induce prostate enlargement; (3) TP-treated group fed a diet containing 5% milled flaxseed; (4) TP-treated group fed a diet containing 10% milled flaxseed; and (5) TP-treated group fed a diet containing 20 ppm finasteride. Treatment with TP significantly increased the absolute and relative weights of different prostatic lobes, serum testosterone (T), and testosterone/estradiol ratio, as well as prostatic vascular endothelial growth factor (VEGF) expression, RNA synthesis per cell, and epithelial cell proliferation, detected as Ki67 labeling. Histopathological examination did not reveal marked differences in acinar morphology in ventral prostate, whereas morphometric analysis showed significantly increased epithelial cell height. Co-administration of flaxseed or finasteride with TP significantly reduced prostatic VEFG, epithelial cell proliferation, and RNA/DNA ratio, along with a significant increase in serum T and testosterone/estradiol ratio compared with TP-only-treated rats. Our results indicate that flaxseed, similar to the 5α-reductase inhibitor finasteride, blocked TP-induced prostate enlargement in a rat model of BPH, likely through suppression of prostatic VEFG and cellular proliferation.

Hormones and prostate carcinogenesis: Androgens and estrogens

Prostate cancer is the leading non-skin malignancy detected in US males and the second cause of death due to male cancer in the US. Androgenic hormones are generally believed to be causatively associated with prostate carcinogenesis, but human evidence, mostly epidemiological, for this is minimal. Circulating hormone levels are not associated with the risk of prostate cancer and neither are polymorphisms in various genes encoding the androgen metabolizing enzymes or androgen receptors. Evidence in support of the involvement of androgens in prostate cancer development is derived from clinical trials with 5α-reductase inhibitors, which reduced the risk by approximately 25%. Animal studies using rat models, however, provide clear evidence that testosterone can induce prostate cancer and can act as a strong tumor promoter in concert with genotoxic carcinogens. One such genotoxic factor may be 17β-estradiol, which is generated from testosterone by the aromatase enzyme. Estradiol can be converted to catecholestrogens, which through redox cycling, generate reactive metabolites that can adduct the DNA and potentially lead to mutations. Animal studies and limited human evidence suggest that estrogens can be involved in prostate carcinogenesis by such a genotoxic mechanism. However, how androgens exert their tumor-promoting effect is not clear. It is likely that hormonal and non-hormonal factors as well as genetic and non-genetic (environmental) factors interact in a highly complex and poorly understood manner to determine the risk of prostate cancer.

5alpha-reductase isozymes and androgen actions in the prostate

Androgens acting via the androgen receptor play critical roles in prostate development, growth, and pathogenesis. There are two potent androgens, testosterone and dihydrotestosterone (DHT), in humans and mammals. DHT is converted from testosterone by 5alpha-reductase isozymes. Two 5alpha-reductase isozymes have been identified. Although both isozymes are expressed, 5alpha-reductase-2 is the predominant isozyme in the human prostate. Mutations in 5alpha-reductase-2 gene cause the 5alpha-reductase-2 deficiency syndrome. Affected 46, XY individuals have a small, nonpalpable, and rudimentary prostate in adulthood. Neither benign prostate hyperplasia (BPH) nor prostate cancer has been reported in these patients. The prostate is small in animals with 5alpha-reductase-2 gene knockout or treated with specific 5alpha-reductase inhibitors. 5alpha-reductase isozymes are molecular targets for the prevention and treatment of BPH and prostate cancer. Moreover, androgen actions on prostate gene expression and cell growth are directly modulated by estrogen receptor ligands via protein-protein interactions. The studies of 5alpha-reductases and androgen actions highlight the importance of 5alpha-reductase isozymes in male sexual differentiation and prostate physiology and pathophysiology.

Prostate cancer prevention

PURPOSE OF REVIEW

Prostate cancer, a common cause of morbidity and mortality in the developed world, ought to be a preventable disease. This review focuses on prostate cancer prevention in the context of new mechanistic insights into human prostatic carcinogenesis.

RECENT FINDINGS

Evidence is accumulating to implicate infection and inflammation as contributors to prostate cancer development. Inherited prostate cancer susceptibility genes discovered thus far encode participants in host responses to infection. Proliferative inflammatory atrophy, a prostate cancer precursor lesion, ties inflammatory responses to prostatic carcinogenesis. Somatic epigenetic alterations, present in all prostate cancers, appear to arise in the setting of inflammation. Finally, a newly identified somatic genome change, involving a fusion between an androgen-regulated gene, TMPRSS2, and genes encoding members of the ETS family of transcription factors, may provide a clue as to why prostate cancer cells exhibit androgen dependence for growth and survival.

SUMMARY

The contributions of infection and inflammation to the early development of prostate cancer suggest prevention strategies featuring prevention or eradication of infection, amelioration of inflammation, or attenuation of genome-damaging reactive oxygen and nitrogen species. The acquisition of androgen dependence later during prostate cancer pathogenesis suggests the use of approaches targeting androgen signaling, including inhibitors of 5alpha-reductase.

Finasteride targets prostate vascularity by inducing apoptosis and inhibiting cell adhesion of benign and malignant prostate cells

BACKGROUND

This study investigated the effects of finasteride, a 5alpha-reductase inhibitor, clinically used for the treatment of benign prostatic hyperplasia (BPH) on prostate tumor vascularity, apoptosis, and cell adhesion in situ and in vitro.

METHODS

Prostate specimens from BPH patients treated with finasteride for 1-12 months (n = 13), or without finasteride treatment (n = 14), were evaluated for apoptosis (TUNEL assay), microvessel density (Factor VIII), and prostate specific antigen (PSA) immunoreactivity. In vitro, the effect of finasteride was investigated in benign prostate cells, BPH-1, and its tumorigenic derivatives, CAFTD-01 and CAFTD-03, using Hoechst staining and cell adhesion assays.

RESULTS

A significant increase in the apoptotic index, and reduced microvessel density and PSA expression were detected in prostates from finasteride-treated patients, compared to controls (P < 0.01). In vitro finasteride led to a significant decrease in prostate epithelial cell adhesion (P < 0.05).

CONCLUSIONS

Finasteride can induce prostate apoptosis and reduce tissue vascularity by inhibiting epithelial cell adhesion. This evidence supports that finasteride has apoptotic and anti-angiogenic effects against benign and malignant prostate.

Regulation of prostate 5alpha-reductase-2 gene expression and prostate weight by dietary fat and caloric intake in the rat

BACKGROUND

High-fat diet is a major risk factor for prostate cancer. 5alpha-reductases are potential targets of dietary fat.

METHODS

Male ACI/Seg rats given either a low-fat or a high-fat diet at weaning or adulthood were sacrificed at 2, 4, and 10 weeks after dietary treatment. Prostate 5alpha-reductase mRNAs, plasma androgens, food consumption, prostate, and body weight were determined.

RESULTS

Prostate 5alpha-reductase-2 mRNA and plasma dihydrotestosterone levels were elevated at 2 weeks, and prostate weight was increased at 10 weeks in neonatal rats fed the high-fat diet. Animals fed the high-fat diet consumed more calories in the first 4 weeks. 5alpha-reductase-1 mRNA, plasma testosterone, and body weight were not different between the two dietary groups. These dietary effects were not observed in adult rats fed the same diets.

CONCLUSION

A high-dietary fat and caloric intake upregulates prostate 5alpha-reductase-2 gene expression, and stimulates prostate growth in neonatal, but not adult rats.

Agents in development for prostate cancer prevention

Accumulated epidemiological evidence indicates that prostate cancer mortality should be preventable. As androgenic hormones have long been recognised to be required for normal prostatic development, and because androgen deprivation is an established treatment for advanced prostate cancer, androgen signalling has been an attractive target for prostate cancer prevention. Inhibitors of 5alpha-reductase, an enzyme necessary for the conversion of testosterone to the more potent androgen dihydrotestosterone, have reached pivotal clinical trials for prostate cancer prevention. In addition, new insights into the molecular pathogenesis of prostate cancer hint that chronic or recurrent prostate inflammation may contribute to the development of the disease. A variety of antioxidants and anti-inflammatory drugs, which are likely to be capable of attenuating pro-carcinogenic genome damage from reactive oxygen and nitrogen species, are also under current development for prostate cancer prevention. This review will consider the rational development of these and other new agents and approaches for prostate cancer prevention in the context of recent research progress in ascertaining the aetiology of prostate cancer.

Persistence of Prostatic Intraepithelial Neoplasia After Effective Chemoprevention of Microscopic Prostate Cancer With Antiandrogen in a Rat Model

PURPOSE

We determined the chemopreventive effect of the antiandrogen bicalutamide (Zeneca Co., Ltd., Osaka, Japan) on Fisher 344 rat prostate carcinogenesis induced by DMAB (3,2'-dimethyl-4-aminobiphenyl) (Nard Co., Ltd., Osaka, Japan). We have previously reported that rat prostate microscopic carcinogenesis in this model was paradoxically enhanced when continuous treatment with bicalutamide was begun 20 weeks after the initiation of DMAB. In the current study we determined whether antiandrogen would promote or suppress the prostate carcinogenesis when administration was begun at a later period of carcinogenesis.

MATERIALS AND METHODS

DMAB at a dose of 50 mg/kg was injected subcutaneously into all animals 10 times at 2-week intervals. To clarify the target lesions of bicalutamide we used 2 control groups (groups 1 and 2). Animals in groups 1 and 2 were autopsied at 60 and 74 weeks, respectively, after the initiation of DMAB. Treatment with bicalutamide began in the 60th week in group 3 rats and continued for 14 weeks. They were sacrificed in the 74th week.

RESULTS

Microscopic cancer was revealed in 27% of group 1 rats and the incidence was increased to 42% in group 2 (statistically not significant). Delayed bicalutamide treatment significantly suppressed the cancer lesion. No cancerous lesion was detected in the ventral or other lobes of the prostate of the rats in group 3. In contrast, bicalutamide did not affect the incidence of PIN. The difference in the incidence of PIN in groups 2 and 3 (84% and 78%, respectively) was not significant.

CONCLUSIONS

The current investigation indicates that, if bicalutamide is started in the later period, it can efficiently eradicate existing microscopic cancer. Despite this suppressive effect on microscopic cancer bicalutamide permits the persistence of PIN. The latter finding suggests that the sensitivity of PIN to antiandrogen might be more complicated than previously recognized.

Linkage and microarray analyses of susceptibility genes in ACI/Seg rats: a model for prostate cancers in the aged

ACI/Seg (ACI) rats develop prostate cancers spontaneously with aging, similar to humans. Here, to identify genes involved in prostate cancer susceptibility, we did linkage analysis and oligonucleotide microarray analysis. Linkage analysis was done using 118 effective rats, and prostate cancer susceptibility 1 (Pcs1), whose ACI allele dominantly induced prostate cancers, was mapped on chromosome 19 [logarithm of odds (LOD) score of 5.0]. PC resistance 1 (Pcr1), whose ACI allele dominantly and paradoxically suppressed the size of prostate cancers, was mapped on chromosome 2 (LOD score of 5.0). When linkage analysis was done in 51 rats with single or no macroscopic testicular tumors, which had larger prostates and higher testosterone levels than those with bilateral testicular tumors, Pcs2 and Pcr2 were mapped on chromosomes 20 and 1, respectively. By oligonucleotide microarray analysis with 8,800 probe sets and confirmation by quantitative reverse transcription-PCR, only two genes within these four loci were found to be differentially expressed >1.8-fold. Membrane metalloendopeptidase (Mme), known to inhibit androgen-independent growth of prostate cancers, on Pcr1 was expressed 2.0- to 5.5-fold higher in the ACI prostate, in accordance with its paradoxical effect. Cdkn1a on Pcs2 was expressed 1.5- to 4.5-fold lower in the ACI prostate. Additionally, genes responsible for testicular tumors and unilateral renal agenesis were mapped on chromosomes 11 and 14, respectively. These results showed that prostate cancer susceptibility of ACI rats involves at least four loci, and suggested Mme and Cdkn1a as candidates for Pcr1 and Pcs2.

Can animal models help us select specific compounds for cancer prevention trials?

Animal models provide unparalleled mechanistic insights into cancer development and potential opportunity for cancer prevention. Nevertheless, species differ markedly with regard to dietary exposures, cancer development, drug effects, and toxicity thresholds; therefore, testing in a single animal system may not predict human responses. Although replication of human cancer in animal models remains inexact, more than two decades of research have clearly yielded significant gains, as is evident in agents tested--and in certain cases, approved--for the prevention of epithelial cancers. Research efficiencies achievable through preliminary testing in genetically engineered and carcinogen-induced animal models enable us to probe genetic and signaling pathways that drive normal and neoplastic processes, and thereby figure prominently in decision trees for agent development.

Prostate carcinogenesis and inflammation: emerging insights

Prostate cancer remains a significant health concern for men throughout the world. Recently, there has developed an expanding multidisciplinary body of literature suggesting a link between chronic inflammation and prostate cancer. In support of this hypothesis, population studies have found an increased relative risk of prostate cancer in men with a prior history of certain sexually transmitted infections or prostatitis. Furthermore, genetic epidemiological data have implicated germline variants of several genes associated with the immunological aspects of inflammation in modulating prostate cancer risk. The molecular pathogenesis of prostate cancer has been characterized by somatic alterations of genes involved in defenses against inflammatory damage and in tissue recovery. A novel putative prostate cancer precursor lesion, proliferative inflammatory atrophy, which shares some molecular traits with prostate intraepithelial neoplasia and prostate cancer, has been characterized. Here, we review the evidence associating chronic inflammation and prostate cancer and consider a number of animal models of prostate inflammation that should allow the elucidation of the mechanisms by which prostatic inflammation could lead to the initiation and progression of prostate cancer. These emerging insights into chronic inflammation in the etiology of prostate carcinogenesis hold the promise of spawning new diagnostic and therapeutic modalities for men with prostate cancer.

Chemoprevention of carcinoma prostate: a review

PURPOSE

Chemoprevention of prostate cancer is the administration of agents to prevent, inhibit, or delay progression of prostate cancer. Opportunities exist for testing various types of chemopreventive interventsion.

MATERIAL AND METHODS

The authors reviewed the relevant articles published in the last twenty years and studied the biology of the prostate cancer. An attempt is made to identify intermediate markers and surrogate endpoint markers. The various interventions and initial clinical trial results are described. End points for evaluation are mainly based on changes in PSA, changes of histological precursors, or time of onset of clinical disease.

RESULTS

Nutritional factors such as reduced fat intake, vitamin A, vitamin E, vitamin C, vitamin D, Lycopene and selenium may have a protective effect against prostate cancer.

CONCLUSION

Numerous studies implicate dietary and nutritional factors in the onset and progression of prostate cancer. Hence, it is possible that bioactive compounds (anti-oxidants) like vits. A, C, D, E, minerals like selenium and carotenoids like lycopene can be a part of chemopreventive strategies for prostate cancer. Ongoing studies on nutrition and prostate cancer may bring the required evidence to support what is still only a hypothesis at present. However, absolute recommendation will have to await the results of long term prospective clinical trials.

Effect of nonsteroidal anti-inflammatory agents and finasteride on prostate cancer risk

PURPOSE

We examine the relationship of nonsteroidal anti-inflammatory drugs and finasteride on the risk of prostate cancer.

MATERIALS AND METHODS

Participants in this case control study using a prospective collection of data were drawn from consecutive patients who underwent prostate biopsy at 12 different departments of urology from January 1999 to June 2000. Medication use was assessed by self-questionnaire as well as questions about dietary and lifestyle factors that might be relevant for prostate cancer risk.

RESULTS

The study included 639 patients with prostate cancer and 659 cancer-free controls. Univariate analysis showed no significant impact of aspirin and finasteride on prostate cancer risk while the nonaspirin nonsteroidal anti-inflammatory drug users had a lower risk (OR 0.80, 95% CI 0.64-0.99). After adjusting for potential confounders, the protective effect of nonaspirin nonsteroidal anti-inflammatory drugs was no longer significant (OR, 0.84, 95% CI 0.66-1.07), while finasteride showed a significant protective effect (OR 0.58, 95% CI 0.37-0.92).

CONCLUSIONS

The results suggest that finasteride could have a chemopreventive role in prostate cancer. While aspirin did not show any impact on prostate cancer risk, the role of nonaspirin nonsteroidal anti-inflammatory drugs warrants further studies.

Inhibition of orthotopic growth and metastasis of androgen-sensitive human prostate tumors in mice by bioactive soybean components

BACKGROUND

Systematic analysis of the influence of diet on the initiation and progression of prostate cancer is often difficult in human populations, for which dietary variables overlap a diversity of genetic backgrounds and social behaviors. Animal models that emulate human prostate cancer allow experimental analysis of the mechanisms of action of nutritional agents that show anti-prostate cancer activity.

METHODS

We have used an orthotopic implant model to characterize the in vivo response of androgen-sensitive LNCaP prostate tumors to three well-characterized soy dietary supplements: isoflavone depleted soy protein, soy phytochemical concentrate (SPC), and genistin.

RESULTS

In male SCID mice orthotopically implanted with the androgen-sensitive human prostate cell line LNCaP, dietary supplements of soy protein, genistin, and SPC reduced primary tumor weight by 42% (P = 0.07), 57% (P < 0.05) and 70% (P < 0.005), respectively. All three soy supplements significantly increased tumor apoptosis and decrease microvessel density, with no significant change in tumor proliferation. Each supplement produced a distinct serum androgen response, with genistin producing the greatest decrease in total serum testosterone and dihydrotestosterone (DHT) (P < 0.05) and the greatest increase in testosterone to DHT ratio (P < 0.05) and soy protein the greatest decrease in bioactive androgen (P < 0.05). Only SPC significantly inhibited metastases to lymph nodes and lungs, and only SPC produced a significant increase in tumor p53 expression.

CONCLUSION

Taken together, these data suggest that the anti-prostate cancer activity of dietary soy protein, soy phytochemicals, and genistin use different molecular pathways. In addition, we have demonstrated that this animal model can be used in the design of dietary strategies for prostate cancer prevention and therapy.

The future of prostate cancer prevention

The dramatic international variation in prostate cancer mortality rates suggest an environmental influence. This combined with a building understanding of the genetic mechanisms of carcinogenesis encourages a search for ways to prevent it. Androgenic stimulation over a period of time has been suggested a cause of prostate cancer. The corollary to this hypothesis is that lowering androgenic stimulation over time will prevent prostate cancer. Decreasing androgenic stimulation of the prostate with 5-alpha-reductase inhibitors such as finasteride has been shown to decrease prostate size and may prevent prostate cancer. A large, long-term clinical trial is underway using finasteride to determine if it can prevent prostate cancer. Results are expected in 2004. Epidemiologic and laboratory studies also suggest that high selenium and vitamin E intake lowers risk of prostate cancer. Recent serendipitous findings of two randomized clinical trials support the hypothesis that selenium and vitamin administration will decrease prostate cancer risk. A study to assess these compounds is beginning. Other promising, but less developed, interventions in chemoprevention of prostate cancer include vitamin D supplementation and diet modification. All will need to be rigorously evaluated before they can be advocated for prostate cancer prevention.

Prostate cancer prevention trials in the USA

There is dramatic international variation in prostate cancer mortality rates. The variation suggests that the disease has an environmental cause and encourages the search for a way to prevent it. Androgenic stimulation over a period of time, perhaps due to a high fat diet, has been suggested as a cause of prostate cancer. The corollary to this hypothesis is that lowering androgenic stimulation over time will prevent prostate cancer. 5-Alpha-reductase inhibition through drugs like finasteride have been shown to decrease androgenic stimulation of the prostate. A clinical trial is underway using finasteride to assess this hypothesis. Epidemiological and laboratory studies also suggest that those with high selenium and vitamin E intake have a lower risk of prostate cancer. Recent serendipitous findings of two randomised clinical trials support this. A study to assess these compounds is currently being designed. Other promising but less developed interventions in the chemoprevention of prostate cancer include vitamin D supplementation and diet modification.

Inhibition of androgen synthesis in human testicular and prostatic microsomes and in male rats by novel steroidal compounds

The C(17,20)-lyase and 5alpha-reductase are key enzymes in the biosynthesis of androgens. The effects of novel steroidal compounds were evaluated as inhibitors against both human C(17,20)-lyase and 5alpha-reductase in vitro. The concentrations of testosterone (T) and dihydrotestosterone (DHT) in the prostate, testis and serum and changes in the tissue weights were also determined in rats treated with the novel inhibitors. L-12 and L-26 showed potent inhibition of human testicular C(17,20)-lyase with IC50 values of 50 and 25 nM, respectively. L-12, L-38, and I-47 showed moderate inhibition of human testicular C(17,20)-lyase with IC50 values of 75, 108, and 70 nM, respectively similar to ketoconazole (78 nM). Interestingly, L-6, L-26, and L-38 also showed some inhibitory activity against 5alpha-reductase with IC50 values of 75, 125, and 377 nM, respectively. Finasteride, an inhibitor of 5alpha-reductase had an IC50 value of 33 nM. However, ketoconazole did not inhibit 5alpha-reductase nor did finasteride inhibit C(17,20)-lyase. Treatment of normal male rats with several of these novel inhibitors (50 mg/kg x day, s.c., for 14 consecutive days) caused about 45-91% decrease in serum, testicular and prostatic T concentration. Similarly, serum and prostatic DHT concentration were significantly decreased in rats treated with these novel compounds by 50-90% compared with controls. Surgical castration caused almost complete elimination of circulating T and DHT concentration in rat tissues. L-6 and L-12 were the most effective and reduced the wet weight of the prostate by 50%. Although future improvements in their bioavailability are necessary, these novel steroidal compounds show promise as potential agents for reducing T and DHT levels in patients with androgen dependent diseases.