Treatment of pain at sexual activity (dyspareunia) with intravaginal dehydroepiandrosterone (prasterone).

OBJECTIVE: This study aims to confirm the local effects of intravaginal prasterone on moderate to severe dyspareunia, a symptom of vulvovaginal atrophy (VVA) associated with menopause. METHODS: In a prospective, randomized, double-blind, placebo-controlled phase III clinical trial, we examined the effects of daily intravaginal prasterone (6.5 mg) on four co-primary objectives, namely, percentage of vaginal parabasal cells, percentage of vaginal superficial cells, vaginal pH, and moderate to severe dyspareunia identified by women as the most bothersome VVA symptom. RESULTS: After daily intravaginal prasterone administration for 12 weeks, the percentage of parabasal cells decreased by 45.8% compared with placebo (P < 0.0001), the percentage of superficial cells increased by 4.7% over placebo (P < 0.0001), and vaginal pH decreased by 0.83 pH units compared with placebo (P < 0.0001). The severity of most bothersome dyspareunia decreased by 46% over placebo (P = 0.013) at 12 weeks, whereas moderate to severe vaginal dryness decreased by 0.43 severity score units (or 42%) compared with placebo (P = 0.013). On gynecologic evaluation, a 14.4% to 21.1% improvement in vaginal secretions, epithelial integrity, epithelial surface thickness, and color over placebo (P = 0.0002 to P < 0.0001) was observed. Serum steroids, in agreement with the physiology of intracrinology and menopause, remained well within reference postmenopausal concentrations. All endometrial biopsies at 12 weeks have shown atrophy. CONCLUSIONS: Daily intravaginal prasterone (0.50%; 6.5 mg) treatment has clinically and statistically significant beneficial effects on the four co-primary objectives of VVA, according to US Food and Drug Administration guidelines. No significant drug-related adverse effect in line with the strictly local action of treatment has been reported, thus providing a high benefit-to-risk ratio for intravaginal prasterone.

Prasterone has parallel beneficial effects on the main symptoms of vulvovaginal atrophy: 52-week open-label study.

OBJECTIVE: An objective was to analyze the time course of efficacy of daily intravaginal administration of 0.5% (6.5mg) DHEA (prasterone) for 52 weeks on the moderate to severe (MS) symptoms and signs of vulvovaginal atrophy (VVA). METHOD: Five hundred twenty-one postmenopausal women were enrolled and received daily intravaginal administration of 0.5% DHEA in an open-label phase III study. The severity of the VVA symptoms examined in detail in the different groups. RESULTS: A parallel improvement of pain at sexual activity was observed in women who had moderate to severe (MS) dyspareunia as their most bothersome symptom (MBS) (n=183) or not MBS (n=240) and MS without being MBS (n=57) with a 1.70 severity unit change in the MBS group for a decrease of 66.1% from baseline (p<0.0001 versus baseline) over 52 weeks. A further improvement of dyspareunia, namely 0.33 severity unit (19.4%), was observed with continuing treatment from 12 weeks to 52 weeks. Similar results were observed on vaginal dryness and irritation/itching. Highly significant beneficial effects (p<0.0001 versus baseline for all) were observed at gynecological examination on vaginal secretions, color, epithelial integrity and epithelial surface thickness. CONCLUSION: The present study shows, in addition to the parallel benefits on the three symptoms of VVA, that the choice of any of the MS symptoms as being or not being MBS by women has no influence on the observed therapeutic effect (NCT01256671).

Lack of influence of dyspareunia on the beneficial effect of intravaginal prasterone (dehydroepiandrosterone, DHEA) on sexual dysfunction in postmenopausal women.

INTRODUCTION: We have previously observed that intravaginal prasterone (dehydroepiandrosterone, DHEA) improved all domains of female sexual dysfunction (FSD). AIM: Investigate the influence of moderate/severe pain at sexual activity (dyspareunia) (MSD) at baseline on FSD following prasterone administration. METHODS: The effect of daily administration of prasterone (0, 3.25 mg, 6.5 mg or 13 mg) for 12 weeks on FSD in 215 postmenopausal women with or without MSD at baseline was evaluated in a prospective, randomized, double-blind, and placebo-controlled phase III clinical trial. MAIN OUTCOME MEASURES: Differences were examined on desire, arousal and orgasm. RESULTS: Comparable benefits were observed in women not having MSD (n = 56) vs. those having MSD (n = 159). The benefits over placebo in prasterone-treated women for desire, avoiding intimacy and vaginal dryness as well as for the total sexual domain of the MENQOL (Menopause Specific Quality of Life) questionnaire, ranged between 18.0% and 38.2% with P values of <0.05 or <0.01 except in one out of 12 subgroups. For the arousal/sensation, arousal/lubrication and summary score of the ASF (Abbreviated Sexual Function) questionnaire, in the MSD+ group, improvements of 64.2% (P = 0.01), 118% (P = 0.001) and 31.1% (P = 0.03) were observed over placebo, respectively, while similar differences (58.0%, 67.6% and 32.1%) did not reach statistical significance in the MSD- group having up to only 44 prasterone-treated women compared with 119 in the MSD+ group. CONCLUSIONS: No MSD at baseline does not apparently affect the effects of intravaginal prasterone on sexual dysfunction. Knowing the absence of significant effects of estrogens on FSD, the present data suggest that vulvovaginal atrophy (VVA) and vulvovaginal sexual dysfunction (VVSD) are two different consequences of sex steroid deficiency at menopause which can respond independently. In addition, the present data seriously question the justification of pain being part of FSD as well as the separation of FSD into separate domains.

The co-chaperone DNAJC12 binds to Hsc70 and is upregulated by endoplasmic reticulum stress.

Human DNAJC12 is a J domain-containing protein whose regulation, subcellular localization, and function are currently unknown. We show here that the abundance of DNAJC12 in human LNCaP prostate cancer cells is upregulated by the stress-inducing drug A23187 and by the stressregulated transcription factor AIbZIP/CREB3L4. The DNAJC12 gene encodes two isoforms, only one of which (isoform a) is expressed in these cells. Immunofluorescence studies showed that a recombinant DNAJC12 protein is diffusely distributed in the cytoplasm. To identify substrates of DNAJC12, we used an immunoaffinity-mass spectrometry approach in cells that express epitope-tagged DNAJC12. The list of potential DNAJC12-binding proteins that were identified in this screen includes several nucleotide-binding proteins. The most frequently identified partner of DNAJC12 in unstressed cells was Hsc70, a cognate Hsp70 chaperone, whereas in stressed cells, the ER chaperone BiP was frequently associated with DNAJC12. Immunoprecipitation experiments confirmed that the endogenous DNAJC12 and Hsc70 proteins interact in LNCaP cells. These results clarify the role of DNAJC12 in the regulation of Hsp70 function.

Intravaginal prasterone (DHEA) provides local action without clinically significant changes in serum concentrations of estrogens or androgens.

In order to avoid the risks of non-physiological systemic exposure, serum concentrations of estradiol (E2) and testosterone (as measured by mass spectrometry-based assays) should remain below the 95th centiles measured at 9.3pg/ml and 0.26ng/ml for these respective sex steroids in normal postmenopausal women. To document the possibility of achieving this therapeutic objective, we have measured individual 24h serum E2 and testosterone concentrations in women with vulvovaginal atrophy (VVA) receiving daily intravaginal administration of a clinically effective dose of 6.5mg prasterone (dehydroepiandrosterone, DHEA). Serum E2 and testosterone, as well as DHEA and nine of its other metabolites, were assayed at ten time intervals over 24h on the first and seventh days of daily vaginal administration of 6.5mg prasterone. No significant change from baseline of average 24h serum E2 or testosterone concentrations was observed. Moreover, average 24h serum DHEA remained within the normal postmenopausal range. Estrone sulfate and the androgen metabolites androsterone glucuronide and androstane-3α, 17ß-diol glucuronide did not change, thus confirming the absence of any biologically relevant systemic exposure to estrogens and androgens, respectively. Serum concentrations of metabolites of both estrogens and androgens remain within the normal postmenopausal range following daily intravaginal administration of 6.5mg prasterone. As other studies have shown, local formation of sex steroids in peripheral tissues without significant release of E2 or testosterone in the circulation can be achieved with intravaginal prasterone. Thus, prasterone is a promising physiological and attractive solution to treating VVA symptoms.

High internal consistency and efficacy of intravaginal DHEA for vaginal atrophy.

Following the compelling data obtained in a pivotal phase III clinical trial performed in 218 postmenopausal women suffering from vaginal atrophy who received daily intravaginal 0.25, 0.5 or 1.0% DHEA (dehydroepiandrosterone) ovules for 12 weeks, we have performed analysis of the four co-primary objectives at each site of that multicentre U.S. and Canadian trial. Comparison was made of the change in percentage of parabasal and superficial cells, vaginal pH and severity of the most bothersome symptom. The site-by-site (seven sites) analysis has shown that 10-13 women per group are generally sufficient to obtain a significant or highly statistically significant decrease in vaginal pH and percentage of parabasal cells and increased percentage of superficial cells at p values ranging from 0.02 to <0.0001. For vaginal pain as the most bothersome symptom, a statistically significant difference from baseline was found at six out of seven sites. The exceptionally high consistency between all sites in this phase III study and high potency of the compound permit to obtain a clinically and statistically significant to highly significant effect of treatment on all parameters of vaginal atrophy with the 0.5% DHEA daily intravaginal dose which does not significantly affect the serum levels of oestrogens, thus avoiding systemic risks.

Effect of intravaginal dehydroepiandrosterone (Prasterone) on libido and sexual dysfunction in postmenopausal women.

OBJECTIVE: The objective of this study was to provide evidence that the transformation of DHEA into both androgens and/or estrogens locally in cells of the three layers of the vagina (epithelium, lamina propria, and muscularis) would have effects of greater impact, including effects on sexual function, than only effects on superficial epithelial cells as achieved with estrogens. METHODS: This prospective, randomized, double-blind, and placebo-controlled phase III clinical trial has evaluated the effect of daily local intravaginal application of Prasterone (dehydroepiandrosterone; DHEA) for 12 weeks on the domains of sexual dysfunction, namely, desire/interest, arousal, orgasm, and pain at sexual activity, in 216 postmenopausal women with moderate to severe symptoms of vaginal atrophy. RESULTS: A time- and dose-dependent improvement of the four domains of sexual function was observed. At the 12-week time interval, the 1.0% DHEA dose led, compared with placebo, to 49% (P = 0.0061) and 23% (P = 0.0257) improvements of the desire domains in the Menopause Specific Quality of Life and Abbreviated Sex Function questionnaires, respectively. Compared with placebo, the Abbreviated Sex Function arousal/sensation domain was improved by 68% (P = 0.006), the arousal/lubrication domain by 39% (P = 0.0014), orgasm by 75% (P = 0.047), and dryness during intercourse by 57% (P = 0.0001). CONCLUSIONS: By a local action in the vagina, DHEA applied daily at doses at which serum steroids remain well within normal postmenopausal values exerts relatively potent beneficial effects on all four aspects of sexual dysfunction. Such data indicate that combined androgenic/estrogenic stimulation in the three layers of the vagina exerts important beneficial effects on sexual function in women without systemic action on the brain and other extravaginal tissues.

Androgens down-regulate myosin light chain kinase in human prostate cancer cells.

Androgens play a major role in the growth and survival of primary prostate tumors. The molecular mechanisms involved in prostate cancer progression are not fully understood but genes that are regulated by androgens clearly influence this process. We searched for new androgen-regulated genes using the Affymetrix GeneChip Human Genome U95 Set in the androgen-sensitive LNCaP prostate cancer cell line. Analysis of gene expression profiles revealed that myosin light chain kinase (MLCK) mRNA levels were markedly down-regulated by the synthetic androgen R1881. The microarray data were confirmed by ribonuclease protection assays. RNA and protein analyses revealed that LNCaP cells express both long (non-muscle) and short (smooth muscle) isoforms, and that both isoforms are down-regulated by androgens. Taken together, these data identify MLCK as a novel downstream target of the androgen signalling pathway in prostate cells.

Serum steroid levels during 12-week intravaginal dehydroepiandrosterone administration.

OBJECTIVE: Because a previous 1-week study has shown no or minimal changes in the serum levels of dehydroepiandrosterone (DHEA) and its metabolites after up to daily 1.8% (23.4 mg) intravaginal DHEA, the objective of the present study was to investigate the serum steroid levels during a 12-week daily intravaginal administration of 0%, 0.25%, 0.5%, and 1.0% DHEA (Prasterone) 1.3 mL ovules. METHODS: In a double-blind, placebo-controlled phase III study, 218 postmenopausal women (age range, 42-74 y) were randomized to receive daily one of four DHEA concentrations intravaginally. Serum steroids were measured by a Good Laboratory Practice-validated mass spectrometry technology in samples obtained at time of visit. RESULTS: The serum levels of DHEA and 11 of its metabolites measured at screening, day 1, and weeks 2, 4, 8, and 12 in women showed no or minimal changes during the whole observation period, with all values remaining well within the limits of normal postmenopausal women. No accumulation of the steroid metabolites nor change in DHEA bioavailability was detected. CONCLUSIONS: The present data show that local daily intravaginal DHEA administration at DHEA doses of 3.25-13 mg was able to rapidly and efficiently achieve correction of all the signs and symptoms of vaginal atrophy and improve sexual function and caused no or minimal changes in serum sex steroid levels, which all remain within the normal postmenopausal range, thus avoiding the risks of all estrogen formulations.

Intravaginal dehydroepiandrosterone (Prasterone), a physiological and highly efficient treatment of vaginal atrophy.

OBJECTIVE: Because the secretion of dehydroepiandrosterone (DHEA), the exclusive source of sex steroids in postmenopausal women, is already decreased by 60% and continues to decline at the time of menopause, the objective of this study was to examine the effect of intravaginal DHEA on the symptoms and signs of vaginal atrophy. METHODS: This prospective, randomized, double-blind and placebo-controlled phase III clinical trial studied the effect of Prasterone (DHEA) applied locally in the vagina on the signs and symptoms of vaginal atrophy in 216 postmenopausal women. RESULTS: All three doses (0.25%, 0.5%, and 1.0%) of DHEA ovules applied daily intravaginally induced a highly significant beneficial change in the percentage of vaginal parabasal and superficial cells and pH as well as in the most bothersome symptom at 2 weeks. At the standard 12-week time interval, 0.5% DHEA caused a 45.9 +/- 5.31 (P < 0.0001 vs placebo) decrease in the percentage of parabasal cells, a 6.8 +/- 1.29% (P < 0.0001) increase in superficial cells, a 1.3 +/- 0.13 unit (P < 0.0001) decrease in vaginal pH, and a 1.5 +/- 0.14 score unit (P < 0.0001) decrease in the severity of the most bothersome symptom. Similar changes were seen on vaginal secretions, color, epithelial surface thickness, and epithelial integrity. Comparable effects were observed at the 0.25% and 1.0% DHEA doses. CONCLUSIONS: Local Prasterone, through local androgen and estrogen formation, causes a rapid and efficient reversal of all the symptoms and signs of vaginal atrophy with no or minimal changes in serum steroids, which remain well within the normal postmenopausal range. This approach avoids the fear of systemic effects common to all presently available estrogen formulations and adds a novel physiological androgenic component to therapy.

Effect of one-week treatment with vaginal estrogen preparations on serum estrogen levels in postmenopausal women.

OBJECTIVE: Approximately 50% of postmenopausal women suffer from vaginal atrophy, and a large proportion of them choose intravaginal estrogen preparations administered for local action to avoid systemic exposure to estrogens and its associated risk of breast and uterine cancer. The primary objective of this study was the evaluation of the systematic bioavailability of estradiol and estrone and the pharmacokinetics of two of the most frequently used intravaginal estrogen preparations, namely Vagifem and Premarin cream. DESIGN: While immunobased assays could not previously provide accurate measurement of serum estrogen concentrations in postmenopausal women, we have used validated mass spectrometry assays to measure the pharmacokinetics of serum estradiol and estrone during the 24 hours following the seventh daily application of 25 microg estradiol (Vagifem) and 1 g (0.625 mg) conjugated estrogens (Premarin) cream in 10 postmenopausal women in each group. RESULTS: Serum estradiol was increased on average by 5.4-fold from 3 to 17 pg/mL during the 24-hour period after daily administration of 25 microg estradiol or 1 g (0.625 mg) conjugated estrogens cream. Serum estrone, conversely, increased 150% with Vagifem and 500% with Premarin cream. CONCLUSIONS: The present data using validated, accurate, and sensitive mass spectrometry assays of estrogens show that the Vagifem pill and Premarin cream, after 1 week of daily treatment, cause an approximately fivefold increase in serum estradiol in postmenopausal women, thus indicating that the effects are unlikely to be limited to the vagina and that systemic actions are expected after application of these intravaginal estrogen preparations.

Effect of intravaginal DHEA on serum DHEA and eleven of its metabolites in postmenopausal women.

The primary objective of this study was measurement of the systemic bioavailability of DHEA and its metabolites following daily intravaginal application of the sex steroid precursor. Forty postmenopausal women were randomized to receive a daily dose of one ovule of the following DHEA concentrations: 0.0%, 0.5%, 1.0% or 1.8%. After only 7 days of treatment, the maturation value of the vaginal epithelial cells was significantly increased while the vaginal pH was significantly decreased at all DHEA doses. These important local effects were observed while the serum concentrations of estradiol and testosterone remained within the values found in normal postmenopausal women at all DHEA doses. Similar observations were made for serum androstenedione, estrone, estrone-sulfate and DHEA-sulfate. Even at the highest 1.8% DHEA dose, serum DHEA was increased at the levels found in normal premenopausal women. The present data show that the intravaginal administration of DHEA permits to rapidly achieve the local beneficial effects against vaginal atrophy without significant changes in serum estrogens, thus avoiding the increased risk of breast cancer associated with the current intravaginal or systemic estrogenic formulations. In addition, the recent observation that DHEA is transformed into both androgens and estrogens in the vagina permits to exert benefits on all the three layers of the vaginal wall.

Androgen-regulated transcription factor AIbZIP in prostate cancer.

Androgen-induced bZIP (AIbZIP/CREB3L4) is a transcription factor of the bZIP family that associates with the membrane of the endoplasmic reticulum (ER). In humans, AIbZIP RNA is most abundant in the prostate gland where the protein is produced in luminal cells of the glandular epithelium. AIbZIP could play an important role in prostate cancer because its expression is up-regulated by androgens in LNCaP prostate cancer cells and the protein is more abundant in cancerous than in non-cancerous prostate cells. We recently added 74 adenocarcinomas and 43 specimens of prostatic intraepithelial neoplasia (PIN) to our survey of AIbZIP expression in prostate tumours. This study showed that AIbZIP is expressed in all grades of adenocarcinoma and that it is more abundant in high-grade PIN and in adenocarcinoma than in normal prostate. The physiological function of AIbZIP remains unknown but its association with the ER and its structural homology to transcription factors such as ATF6 suggest that AIbZIP could be activated by regulated intramembrane proteolysis during the cellular response to ER stress. This review will describe the characteristics of human and mammalian AIbZIP, its relationship to prostate cancer, and our recent efforts to characterize the transcriptional properties and targets of AIbZIP.

Transcriptional profiling of genes that are regulated by the endoplasmic reticulum-bound transcription factor AIbZIP/CREB3L4 in prostate cells.

The androgen-regulated protein androgen-induced bZIP (AIbZIP) is a bZIP transcription factor that localizes to the membrane of the endoplasmic reticulum (ER). The physiological role of AIbZIP is unknown, but other ER-bound transcription factors such as ATF6 and SREBPs play a crucial role in the regulation of protein processing and lipid synthesis, respectively. In response to alterations in the intracellular milieu, ATF6 and SREBPs are processed to their transcriptionally active forms by regulated intramembrane proteolysis. In humans, AIbZIP mRNA is expressed in several organs including the pancreas, liver, and gonads, but it is especially abundant in prostate epithelial cells. We therefore used LNCaP human prostate cancer cells as a model to identify stimuli that lead to AIbZIP activation and define the transcriptional targets of AIbZIP. In LNCaP cells, AIbZIP was processed to its transcriptionally active form by drugs that deplete ER calcium stores (i.e., A23187 and caffeine), but it was unaffected by an inhibitor of protein glycosylation (tunicamycin). To identify AIbZIP-regulated genes, we generated LNCaP cell lines that conditionally express the processed form of AIbZIP and used Affymetrix microarrays to screen for AIbZIP-regulated transcripts. Selected genes (n = 48) were validated by Northern blot hybridization. The results reveal that the downstream targets of AIbZIP include genes that are implicated in protein processing (e.g., BAG3, DNAJC12, KDELR3). Strikingly, a large number of AIbZIP-regulated transcripts encode proteins that are involved in transcriptional regulation, small molecule transport, signal transduction, and metabolism. These results suggest that AIbZIP plays a novel role in cell homeostasis.

Characterization of the RSL1-dependent conditional expression system in LNCaP prostate cancer cells and development of a single vector format.

BACKGROUND: Conditional expression systems are useful tools for the study of gene function but the use of these systems in prostate cancer cells is limited by the undesired biological effects of the inducing ligands. The RheoSwitch system employs RheoSwitch Ligand 1 (RSL1), a non-steroidal analog of the insect hormone ecdysone, to activate a modified nuclear receptor heterodimer that controls target gene expression via GAL4 response elements. This system has not been tested in prostate cancer cells. METHODS: We established LNCaP human prostate cancer cell lines that constitutively express RheoSwitch transcription factors to quantify RSL1-dependent expression and assess the effects of RSL1 on cell proliferation and endogenous gene expression. Potential RSL1-responsive genes were identified using Affymetrix microarrays and validated by Northern blot hybridization. A single-vector format was developed to establish cell lines that conditionally produce a recombinant protein. RESULTS: Stable cell lines displayed tight and potent (over several orders of magnitude) RSL1-dependent regulation of a transiently transfected luciferase reporter gene. RSL1 did not affect basal or androgen-stimulated cell proliferation and exerted minimal effects on the expression of endogenous genes. Cell lines established using the single-vector system also displayed strictly RSL1-dependent production of the recombinant protein encoded by the stably integrated RSL1-responsive expression cassette. CONCLUSIONS: The RheoSwitch system is well suited for conditional gene expression in prostate cancer cells. The single-vector format should facilitate the production of stable cell lines. This system should be useful for the study of proteins involved in prostate cancer in both cell and animal models of the disease.

Evaluation of AIbZIP and Cdc47 as markers for human prostatic diseases.

OBJECTIVES: Benign prostatic hyperplasia and prostate cancer are important public health issues. However, histologic markers for these diseases are limited. METHODS: Immunocytochemistry was used to analyze the cellular localization of AIbZIP, Cdc47, androgen receptor and estrogen receptor-beta markers. AIbZIP is a protein recently found to be more abundant in prostate cancer than in benign prostatic tissue, and Cdc47 is a cell proliferation-associated protein. The localization and modulation of androgen receptor and estrogen receptor-beta through the carcinogenesis process have been examined in several studies but controversial results were obtained. These four proteins were evaluated as potential markers of prostatic diseases in 210 needle core biopsies, including normal prostate, benign prostatic hyperplasia, low-grade and high-grade prostatic intraepithelial neoplasia, and different Gleason grades of prostatic adenocarcinoma. RESULTS: Androgen receptor and estrogen receptor-beta do not discriminate between benign and malignant specimens, while AIbZIP was able to distinguish between them. Cdc47, in contrast, discriminated not only between malignant and benign prostatic tissue, but also between benign prostatic hyperplasia and normal prostatic tissue. CONCLUSIONS: Cdc47 appears to be a sensitive marker of prostatic diseases since its expression gradually increased in parallel with the severity of the lesion. AIbZIP discriminated between benign tissue and cancer. AIbZIP and Cdc47 thus appear to be useful markers with diagnostic and prognostic values.

Dehydroepiandrosterone (DHEA) is an anabolic steroid like dihydrotestosterone (DHT), the most potent natural androgen, and tetrahydrogestrinone (THG).

We have recently taken advantage of the unique power of DNA microarrays to compare the genomic expression profile of tetrahydrogestrinone (THG) with that of dihydrotestosterone (DHT), the most potent natural androgen, thus clearly demonstrating that THG is an anabolic steroid. In 2004, the U.S. Controlled Substances Act has been modified to include androstenedione (4-dione) as an anabolic steroid. However, despite the common knowledge that dehydroepiandrosterone (DHEA) is the precursor of testosterone, DHEA has been excluded from the list of anabolic steroids. We thus used the same DNA microarray technology to analyze the expression profile of practically all the 30,000 genes of the mouse genome modulated by DHEA and DHT in classical androgen-sensitive tissues. Daily subcutaneous injections of DHT (0.1mg) or DHEA (3mg) for 1 month in gonadectomized C57BL6/129 SV mice increased ventral prostate, dorsal prostate, seminal vesicle and preputial gland weight (p<0.01 for all tissues). As early as 24h after single injection of the two steroids, 878, 2681 and 14 probe sets were commonly stimulated or inhibited (p<0.01, change> or =30%), in the prostate (ventral+dorsal), seminal vesicles and preputial glands, respectively, compared to tissues from gonadectomized control animals. After 7 days of daily treatment with DHEA and DHT, 629, 919 and 562 probe sets were commonly modulated in the same tissues while after 27 days of treatment, 1195, 5127 and 2883 probe sets were modulated, respectively. In analogy with the data obtained with THG, the present microarray data provide an extremely precise and unquestionable genomic signature and proof of the androgenic/anabolic activity of DHEA. Such data add to the literature showing that DHEA is transformed into androgens in the human peripheral tissues as well as in laboratory animal species, including the monkey, thus exerting potent androgenic/anabolic activity. The present microarray approach to identify anabolic compounds is applicable to all potential androgenic/anabolic compounds.

Stage-specific expression of the Atce1/Tisp40alpha isoform of CREB3L4 in mouse spermatids.

The maturation of haploid spermatids into spermatozoa relies on the timely production of proteins required for spermatid differentiation. The mammalian CREB3L4 (cAMP responsive element binding protein 3-like 4) gene encodes a bZIP transcription factor that associates with the membrane of the endoplasmic reticulum. CREB3L4 is presumed to play an important role in protein maturation via its involvement in the cellular response to endoplasmic reticulum stress. In mice, the Creb3l4 gene gives rise to 2 distinct classes of mRNAs through the use of alternate promoters. Transcripts that initiate upstream of the first coding exon encode a 370-amino acid (aa) protein designated Tisp40beta, whereas transcripts that initiate downstream of the first coding exon encode Atce1/Tisp40alpha, a truncated (315-aa) form of Tisp40beta. In the mouse testis, Creb3l4 transcripts are known to be expressed exclusively in postmeiotic spermatids but the presence of CREB3L4 protein in spermatids has not been formally demonstrated. We produced an antibody directed against the carboxy terminus of mouse CREB3L4 and used it in immunostaining experiments to document that CREB3L4 protein accumulates in post-meiotic spermatids in a stage-specific manner. Moreover, we show that Atce1/Tisp40alpha is the major form of CREB3L4 in mouse testis. These findings suggest that testis-specific isoforms of Creb3l4 could play an important role in spermatid differentiation.

Gonadotropin-releasing hormone agonists in the treatment of prostate cancer.

In 1979, the first prostate cancer patient was treated with a GnRH agonist at the Laval University Medical Center in Quebec City, Canada, thus rapidly leading to the worldwide replacement of surgical castration and high doses of estrogens. The discovery of medical castration with GnRH agonists was soon followed by fundamental changes in the endocrine therapy of prostate cancer. Most importantly, the excellent tolerance accompanying the treatment with GnRH agonists has been a key factor that permitted a series of studies demonstrating a major reduction in the death rate from prostate cancer ranging from 31 to 87% at 5 yr of follow-up in patients with localized or locally advanced prostate cancer. In fact, a one third reduction in prostate cancer deaths has been calculated in the metaanalysis of all available studies. The general acceptance of this discovery by patients and physicians is illustrated by world sales above 3.0 billion U.S. dollars in 2003. Although extremely efficient in achieving complete medical castration and well tolerated, with no other side effects than the expected hypoandrogenicity, GnRH agonists should not be administered alone. In fact, shortly after discovery of the castration effects of GnRH agonists, we observed that approximately 50% of androgens remain in the prostate after castration, thus leading to the recognition of the role of adrenal dehydroepiandrosterone as an important source of the androgens synthesized locally in the prostate and in many peripheral target tissues. We therefore developed combined androgen blockade (CAB), whereby the androgens of both testicular and adrenal origins are blocked simultaneously at start of treatment with the combination of a GnRH agonist to block the testis and a pure antiandrogen to block the action of the androgens produced locally. CAB, first used in advanced metastatic disease, has been the first treatment shown to prolong life in prostate cancer. Most interestingly, in 2002, we made the observation that CAB alone given continuously for 6.5 yr or more leads to cure of the disease in at least 90% of cases, thus suggesting that androgen blockade combining a GnRH agonist and a pure antiandrogen could well be the most efficient treatment of localized prostate cancer, and thus offering the possibility of practically eliminating death from prostate cancer.

Tetrahydrogestrinone induces a genomic signature typical of a potent anabolic steroid.

Tetrahydrogestrinone (THG) is a recently identified compound having the greatest impact in the world of sports. In order to obtain a highly accurate and sensitive assessment of the potential anabolic/androgenic activity of THG, we have used microarrays to identify its effect on the expression of practically all the 30,000 genes in the mouse genome and compared it with the effect of dihydrotestosterone (DHT), the most potent natural androgen. Quite remarkably, we found that 671 of the genes modulated by THG in the mouse muscle levator ani are modulated in a similar fashion by DHT, while in the gastrocnemius muscle and prostate, 95 and 939 genes respectively, are modulated in common by the two steroids. On the other hand, THG is more potent than DHT in binding to the androgen receptor, while, under in vivo conditions, THG possesses 20% of the potency of DHT in stimulating prostate, seminal vesicle and levator ani muscle weight in the mouse. The present microarray data provide an extremely precise and unquestionable signature of the androgenic/anabolic activity of THG, an approach which should apply to the analysis of the activity of any anabolic steroid.