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Dive into the research topics where José Luis Gomez is active.

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Featured researches published by José Luis Gomez.


The Journal of Steroid Biochemistry and Molecular Biology | 2006

Androgen glucuronides, instead of testosterone, as the new markers of androgenic activity in women

Fernand Labrie; Alain Bélanger; Patrick Bélanger; René Bérubé; Céline Martel; Leonello Cusan; José Luis Gomez; Bernard Candas; Isabelle Castiel; Véronique Chaussade; Claire Deloche; Jacques Leclaire

Despite the long series of cohort studies performed during the last 20 years, the correlation between serum testosterone and any clinical situation believed to be under androgen control in women has remained elusive. This is likely related to the recent finding that the androgens made locally in large amounts in peripheral tissues from the precursor dehydroepiandrosterone (DHEA) act in the same cells where synthesis takes place and are not released in significant amounts in the circulation, thus making unreliable the measurement of serum testosterone as marker of total androgenic activity. The objective is to determine if serum androgen glucuronides can be replaced by testosterone or another steroid as measure of androgenic activity. Since the glucuronide derivatives of androgens are the obligatory route of elimination of all androgens, these metabolites were measured by liquid chromatography tandem mass spectrometry under basal conditions in 377 healthy postmenopausal women aged 55-65 years as well as in 47 premenopausal women aged 30-35 years while testosterone was assayed by gas chromatography mass spectrometry. No correlation was found between the serum concentration of testosterone and that of androsterone glucuronide (ADT-G) or androstenediol glucuronide (3alpha-diol-G), the androgen metabolites which account for the total pool of androgens. The present data show that measurement of the total pool of androgens reflected by the serum levels of ADT-G and 3alpha-diol-G cannot be replaced by serum testosterone or any other steroid, including DHEA or DHEA sulphate. These findings may have implications for women with androgen deficiency involving osteoporosis, obesity, type 2 diabetes, sexual dysfunction, loss of muscular strength and a series of other clinical situations affecting womens health. Measuring ADT-G and 3alpha-diol-G might identify cases of true androgen deficiency and provide an opportunity to offer appropriate androgen therapy.


The American Journal of Surgical Pathology | 1996

Effect of neoadjuvant endocrine therapy (combined androgen blockade) on normal prostate and prostatic carcinoma : a randomized study

Luc Vaillancourt; Bernard Têtu; Yves Fradet; André Dupont; José Luis Gomez; Leonello Cusan; E. Raul Suburu; Pierre Diamond; Bernard Candas; Fernand Labrie

The morphologic changes induced by neoadjuvant combination endocrine therapy were evaluated in prostatectomy specimens from patients diagnosed with localized prostate cancer. These patients participated in a prospective, randomized clinical trial investigating the effect of 3 months of combination therapy with flutamide and an LHRH agonist prior to radical prostatectomy versus radical prostatectomy alone. Ninety-six radical prostatectomy specimens processed according to the same protocol were evaluated without knowledge of prior treatment. Forty-seven patients were randomly assigned to the neoadjuvant combination therapy group and 49 to the control arm. Compared with the control group, several changes were strongly and significantly associated with exposure to neoadjuvant combination therapy. The nonmalignant prostatic tissue showed strong prominence and hyperplasia of the basal cell layer, accompanied by epithelial cell vacuolization and markedly reduced occurrence of prostatic intraepithelial neoplasia (p < 0.001) after combination therapy. Prostate cancer tissue, on the other hand, showed smaller nucleoli (p < 0.001), cell vacuolization (p < 0.001), rare intraluminal crystalloids (p < 0.001), higher Gleason grade (p < 0.001), lower prevalence of capsular penetration (p < 0.001), and less frequent invasion of the perineural spaces (p < 0.001) and surgical margins (p = 0.002). Tumor volume, was also reduced by more than 40% in the treated group (p = 0.007). The present findings show that preoperative endocrine combination therapy induces highly characteristic changes in both nonmalignant and cancerous prostatic tissue. Furthermore, following endocrine treatment, the surgical margins are less likely to be involved by cancer and capsular penetration is reduced.


The Journal of Steroid Biochemistry and Molecular Biology | 2007

Metabolism of DHEA in postmenopausal women following percutaneous administration

Fernand Labrie; Alain Bélanger; Patrick Bélanger; René Bérubé; Céline Martel; Leonello Cusan; José Luis Gomez; Bernard Candas; Véronique Chaussade; Isabelle Castiel; Claire Deloche; Jacques Leclaire

The marked decline in serum dehydroepiandrosterone (DHEA) with age is believed to play a role in health problems associated with aging, these health issues being potentially preventable or reversible by the exogenous administration of DHEA. In the present study, liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) and gas chromatrography/mass spectrometry (GC/MS) were used to measure the serum levels of DHEA and 11 of its metabolites in seventy-five 60-65-year-old Caucasian women who received 3g of 0.1%, 0.3%, 1.0% or 2.0% DHEA cream or placebo applied twice daily on the face, upper chest, arms and legs. The serum levels of DHEA increased 574% over control at the 2.0% DHEA dose while the sum of the androgen metabolites androsterone glucuronide (ADT-G), 3alpha-androstenediol-3G (3alpha-diol-3G) and 3alpha-diol-17G increased by only 231%. On the other hand, serum testosterone and dihydrosterone were increased by 192% and 275%, respectively, above basal levels compared to 139% and 158% for estrone and estradiol. Such data show that the transformation of exogenous DHEA in postmenopausal women is preferentially into androgens rather than into estrogens. On the other hand, the present data indicate that serum DHEA measurements following DHEA supplementation in postmenopausal women are an overestimate of the formation of active androgens and estrogens and suggest a decreased efficiency of transformation of DHEA into androgens and estrogens with aging.


The Journal of Steroid Biochemistry and Molecular Biology | 2009

Comparable amounts of sex steroids are made outside the gonads in men and women: strong lesson for hormone therapy of prostate and breast cancer.

Fernand Labrie; Leonello Cusan; José Luis Gomez; Céline Martel; René Bérubé; Patrick Bélanger; Alain Bélanger; Liesbeth Vandenput; Dan Mellström; Claes Ohlsson

The objective of this study was comparison of circulating androgens and their metabolites as well as estrogens measured for the first time by a validated mass spectrometry technology in 60-80-year-old men and women of comparable age. Castration in men (n=34) reduces the total androgen pool by only about 60% as indicated by the decrease in the serum levels of the glucuronide metabolites of androgens compared to intact men (n=1302). Such data are in agreement with the 50 to 75% decrease in intraprostatic dihydrotestosterone (DHT) concentration after castration. Most interestingly, the same amounts of androgens and estrogens are found in postmenopausal women (n=369) and castrated men of comparable age. The most significant therapeutic implication of these findings is the absolute need to add a pure (nonsteroidal) antiandrogen to castration in men with prostate cancer in order to block the action of the 25 to 50% DHT left in the prostate after castration. Not adding an antiandrogen to castration in men treated for prostate cancer is equivalent to not prescribing a blocker of estrogens in women suffering from breast cancer because they are postmenopausal and have low circulating estradiol.


The Journal of Steroid Biochemistry and Molecular Biology | 2008

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

Fernand Labrie; Leonello Cusan; José Luis Gomez; Isabelle Côté; René Bérubé; Patrick Bélanger; Céline Martel; Claude Labrie

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.


The Journal of Steroid Biochemistry and Molecular Biology | 2008

Corrigendum to “Effect of intravaginal DHEA on serum DHEA and eleven of its metabolites in postmenopausal women” [Journal of Steroid Biochemistry and Molecular Biology (2008) 178–194]

Fernand Labrie; Leonello Cusan; José Luis Gomez; Isabelle Côté; René Bérubé; Patrick Bélanger; Céline Martel; Claude Labrie

Fig. 7. Average 24-h serum concentrations (AUC0-24h/24) of DHEA, 5-Diol, DHEA-S, 4-Dione, testo and DHT measured on days 1 and 7 following once daily administration of vaginal ovules containing 0%, 0.5%, 1.0% or 1.8% DHEA as well as baseline serum steroid levels. Data are expressed as means± S.E.M. (n=8 to 10). Testo levels from one patient in the placebo group were excluded (n=8 in that group). Serum steroid concentrations measured in 30–35-year-old premenopausal (n=47) as well as in 55–65-year-old postmenopausal (n=377) women are added as reference data which are expressed as means and 5th and 95th centiles (dashed lines). *p<0.05, **p<0.01, experimental (day 1 and day 7) vs. baseline.


The Journal of Pathology | 1998

Cycling activity of benign prostatic epithelial cells during long-term androgen blockade: evidence for self-renewal of luminal cells.

Theodorus H. van der Kwast; Bernard Têtu; E. Raoul Suburu; José Luis Gomez; Martin Lemay; Fernand Labrie

Combined androgen blockade (CAB) therapy (LHRH agonist and flutamide) for 6 months leads to marked regressive changes of the prostate gland. This is associated with a reduction in the ratio of luminal to basal cells in the peripheral zone (PZ) in hyperplastic glands of the transitional zone (TZ). To examine the cycling activity of luminal and basal cells, double immunostaining was performed. For precise definition of basal cells, the basal cell‐specific antibody 34βE12 was used, while cycling cells were identified by the MIB‐1 antibody. In 6‐month‐treated specimens, the fraction of cycling luminal cells increased from 03 to 25 per cent in the PZ and from 02 to 39 per cent in the TZ. This was associated with an inversion of the ratio of MIB‐1‐labelled luminal to basal cells, with values of 57:1 (PZ) and 39:1 (TZ), compared with 1:4 (PZ) and 1:5 (TZ) in untreated specimens. The predominance continued for at least 11 years of CAB. The findings strongly suggest that luminal cells are capable of self‐renewal under conditions of low androgen levels. The substantial decrease of prostatic volume on long‐term CAB implies that cell loss outweighs cell proliferation. Copyright


The Journal of Steroid Biochemistry and Molecular Biology | 2004

Major impact of hormonal therapy in localized prostate cancer--death can already be an exception.

Fernand Labrie; Leonello Cusan; José Luis Gomez; Van Luu-The; Bernard Candas; Alain Bélanger; Claude Labrie

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. A long series of studies have clearly demonstrated that medical castration with an LHRH agonist has inhibitory effects on prostate cancer equivalent to those of surgical castration. The much higher acceptability of LHRH agonists has been essential to permit a series of studies in localized disease. Based upon the finding that the testicles and adrenals contribute approximately equal amounts of androgens in the human prostate, the combination of medical (LHRH agonist) or surgical castration associated with a pure antiandrogen (flutamide, nilutamide or bicalutamide) has led to the first demonstration of a prolongation of life in prostate cancer, namely a 10-20% decreased risk of death according to the various metaanalyses of all the studies performed in advanced disease. In analogy with the other types of advanced cancers, the success of combined androgen blockade in metastatic disease is limited by the development of resistance to treatment. To avoid the problem of resistance to treatment while taking advantage of the relative ease of diagnosis of prostate cancer at an early stage, the much higher acceptability of LHRH agonists has permitted a series of studies which have demonstrated a major reduction in deaths from prostate cancer ranging from 31% to 87% at 5 years of follow-up in patients with localized or locally advanced prostate cancer. Most importantly, recent data show that the addition of a pure antiandrogen to an LHRH agonist in order to block the androgens made locally in the prostate leads to a 90% long-term control or probable cure of prostate cancer.


The Journal of Urology | 2006

Relationship Among Initial Serum Prostate Specific Antigen, Prostate Specific Antigen Progression and Prostate Cancer Detection at Repeat Screening Visits

Bernard Candas; Fernand Labrie; José Luis Gomez; Leonello Cusan; Eric Chevrette; Jacques Lévesque; Ghyslain Brousseau

PURPOSEnWe evaluated the probability of positive serum PSA (3 ng/ml or greater) and CaP detection at annual followup visits in men with negative initial PSA (less than 3 ng/ml) to optimize the re-screening schedule.nnnMATERIALS AND METHODSnData on 5,387 men 45 to 80 years old with negative PSA and no CaP diagnosis at the first screening visit were obtained from the Laval University Prostate Cancer Screening Program database. Accelerated failure time regressions were fitted to time from baseline to positive PSA and to time from positive PSA to CaP detection. The models were combined to estimate the cumulative probability of positive PSA followed by CaP detection at re-screening.nnnRESULTSnThe 5-year cumulative probability of detecting CaP at annual visits in men with baseline PSA up to 1.5 ng/ml remained below 0.8%, while it was 1.3%, 4.8% and 8.3% in men with PSA 1.5 to less than 2, 2 to less than 2.5 and 2.5 to less than 3 ng/ml, respectively. Time to positive PSA significantly decreased with increasing baseline PSA and age, while the time between positive PSA and CaP detection depended only on age. Men with PSA below 1.0 ng/ml could wait for 4 to 5 years before being re-tested, while men with PSA between 1.0 and 1.5 ng/ml should be screened every second year and men with PSA 1.5 ng/ml or greater should be screened every year.nnnCONCLUSIONSnThe proposed retesting schedule using current PSA and age decreases the number of visits by 38.1%, while delaying the detection of only 2.4% of CaPs that would have been detected using annual PSA testing.


The Prostate | 2004

Screening decreases prostate cancer mortality: 11‐year follow‐up of the 1988 Quebec prospective randomized controlled trial

Fernand Labrie; Bernard Candas; Lionel Cusan; José Luis Gomez; Alain Bélanger; Ghyslain Brousseau; Eric Chevrette; Jacques Lévesque

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