Publications by authors named "Claude Labrie"

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).

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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Article Synopsis
  • Benign prostatic hyperplasia and prostate cancer are significant public health concerns, but effective histological markers for these conditions are currently limited.
  • This study utilized immunocytochemistry to analyze four protein markers (AIbZIP, Cdc47, androgen receptor, and estrogen receptor-beta) in 210 prostate biopsies, with AIbZIP being more prevalent in cancerous tissue and Cdc47 linked to cell proliferation.
  • Results showed AIbZIP effectively differentiates between benign and malignant tissues, while Cdc47 correlates with disease severity, indicating both AIbZIP and Cdc47 could serve as valuable diagnostic and prognostic markers for prostatic diseases.
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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.

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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.

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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.

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For about 50 years, androgen blockade in prostate cancer has been limited to monotherapy (surgical castration) or high doses of estrogens in patients with advanced disease and bone metastases. The discovery of medical castration with LHRH agonists has led to fundamental changes in the endocrine therapy of prostate cancer. In 1979, the first prostate cancer patient treated with an LHRH agonist received such treatment at the Laval University Medical Center.

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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.

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Objective: To describe the genomic expression profile or transcriptome of adipose tissue using the serial analysis of gene expression method.

Research Methods And Procedures: The serial analysis of gene expression strategy is based on isolation of short sequences (tags), which usually correspond to unique transcripts, and on their concatenation into long DNA molecules, which are then cloned and sequenced. Experiments were performed with mRNA from retroperitoneal adipose tissue of male C57BL6 mice.

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In men, orchiectomy (GDX) produces an atherogenic lipid profile, whereas combined androgen blockade (CAB) induces a favorable lipid pattern. To better understand the opposite effects of GDX and CAB on lipid metabolism, we have compared the changes in plasma lipoproteins, mesenteric fat metabolism, as well as serum and intratissular sex steroid concentrations in intact, GDX, and GDX+FLU [GDX male cynomolgus monkeys treated for 3 months with flutamide (FLU)]. Serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulfate (DHEA-S), and androstenediol remained stable after GDX.

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Purpose: To determine the efficacy and safety of EM-800 (SCH-57050), the precursor of acolbifene, a new, highly potent, orally active, pure antiestrogen in the mammary gland and endometrium, for the treatment of tamoxifen-resistant breast cancer.

Patients And Methods: Forty-three post menopausal/ovariectomized women with breast cancer who had received tamoxifen, either for metastatic disease or as adjuvant to surgery for > or = 1 year, and had relapsed were treated in a prospective, multicenter, phase II study with EM-800 (20 mg/d [n = 21] or 40 mg/d [n = 22] orally). Results Thirty-seven patients had estrogen receptor (ER)-positive tumors (>10 fmol/mg; mean, 146 fmol/mg cytosolic protein), three patients had ER-negative/progesterone receptor-positive tumors, and three patients had undetermined ER status.

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The NEDD4L gene encodes a ubiquitin ligase that targets the epithelial sodium channel for degradation. A search for transcripts whose levels increase following androgen treatment of LNCaP human prostate cancer cells led to the isolation of three new NEDD4L transcripts designated NEDD4Lf, NEDD4Lg and NEDD4Lh. The three transcripts encode different forms of the NEDD4L protein, two of which contain an N-terminal C2 domain.

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