Christian Huidobro - Academia.edu (original) (raw)

Papers by Christian Huidobro

Research paper thumbnail of Effect of GnRH analogs on the expression of TrkA and p75 neurotrophin receptors in primary cell cultures from human prostate adenocarcinoma

The Prostate, 2005

BACKGROUND. GnRH analogs have antiproliferative and/or apoptotic effects on prostate cancer cells... more BACKGROUND. GnRH analogs have antiproliferative and/or apoptotic effects on prostate cancer cells. Also, neurotrophin receptors TrkA and p75 have been reported in normal prostate suggesting a role in the gland growth control. In prostate cancer, TrkA receptors seem to be overexpressed and p75 receptors show a decreased expression. These changes in neurotrophin receptors may be related with unbalanced growth in malignant cells. In the present study we investigate the effects of GnRH analogs (leuprolide and cetrorelix) on the expression of TrkA and p75 neurotrophin receptors in primary cultures of human prostate cancer cells. METHODS. Tissue was obtained from radical prostatectomies due to prostate adenocarcinoma. Cells were isolated after sequential enzyme digestion and cultured in defined media. Nerve growth factor (NGF) receptors in untreated cultures were estimated by immunofluorescence. Cultures were treated with leuprolide (agonist) or cetrorelix (antagonist) and expression of TrkA and p75 receptors were evaluated by semi quantitative RT-PCR (polymerase chain reaction) and western blot. Cell proliferation was estimated by MTT method and apoptosis through COMET assay. RESULTS. Both leuprolide and cetrorelix induced a significant increase in p75 receptor gene and protein expression at a concentration that induce apoptosis and decrease proliferation. TrkA receptors showed no changes in presence of GnRH analogs. CONCLUSIONS. GnRH analogs, leuprolide, and cetrorelix, change the ratio between neurotrophin receptors TrkA and p75 by increasing gene and protein expression of p75 receptor. Considering that TrkA receptor is related with proliferation and p75 with apoptosis, we suggest that our findings may explain, in part, the effect of GnRH analogs on prostate cancer growth.

Research paper thumbnail of SCHU-48: Impact of Body Mass Index in Patients Undergoing Transrectal Biopsy for Prostate Cancer Screening

Research paper thumbnail of Secretion of Glycosidases in Human Epididymal Cell Cultures

Archives of Andrology, 2000

The dynamics of glycosidase secretion was evaluated in human epididymal cell culture. Epithelial ... more The dynamics of glycosidase secretion was evaluated in human epididymal cell culture. Epithelial cells from caput, corpus, and cauda epididymis were isolated from tissue obtained from patients undergoing therapeutic orchidectomy due to prostatic carcinoma. The activities of a-glucosidase, N-acetylglucosaminidase, b-glucuronidase, and a-mannosidase were analyzed in conditioned culture media. Glycosidase activity was significantly higher in corpus and/or cauda than in caput epididymis. There was a time-dependent increase in enzyme activities that was maximal between 10 and 14 days of culture in all epididymal regions. Epididymal glycosidases are secreted by cultured epithelial cell from human epididymis with an increase toward the distal regions of this organ, which may be related to the dynamics of sperm maturation. Cultures from different epididymal regions may represent a valuable tool to study of human epididymal function.

Research paper thumbnail of Androgen regulation of glycosidase secretion in epithelial cell cultures from human epididymis

Human Reproduction, Jun 1, 1999

The human epididymis and its secretions actively promote sperm fertilizing capacity and provide p... more The human epididymis and its secretions actively promote sperm fertilizing capacity and provide protection for spermatozoa against harmful influences. Among epididymal secretions, glycosidases have been recently studied and associated with molecular changes on the sperm surface. In the present work, we studied the influence of different concentrations of testosterone, dihydrotestosterone and cyproterone acetate on the secretion of α-glucosidase, Nacetyl-glucosaminidase, β-glucuronidase and α-mannosidase by isolated and cultured epithelial cells from human caput, corpus and cauda epididymides. Cell cultures were obtained from aggregates of isolated tubule fragments plated on extracellular matrix-covered multi-well plates. Activities of the glycosidases were measured in conditioned culture media and were higher in the distal regions of the epididymis. Testosterone and dihydrotestosterone significantly increase the enzyme secretion in a concentrationdependent manner. This increase was higher in corpus and/or cauda than in caput epididymis. Cyproterone acetate caused a dose-dependent decrease in glycosidase secretion in cultures from all epididymal regions. It is concluded that the secretion of epididymal glycosidases is regulated by androgen, being stimulated by dihydrotestosterone and testosterone and inhibited by the androgen antagonist cyproterone acetate.

Research paper thumbnail of Infertilidad masculina

Revista Médica Clínica Las Condes, May 1, 2010

RESUMEN Se estima que aproximadamente un 15% de las parejas son incapaces de concebir luego de un... more RESUMEN Se estima que aproximadamente un 15% de las parejas son incapaces de concebir luego de un año de relaciones sexuales no protegidas; 30% son debidas a factor femenino y 30% a factor masculino. El 40% restante es de causa mixta. La evaluación inicial de rutina en el varón (que incluye una detallada historia clínica, examen físico y test básicos como perfil hormonal y análisis seminal) es por lo tanto esencial para la mejoría de su fertilidad. El varicocele, criptorquidia no tratada y las infecciones del tracto urogenital son las causas identificables más frecuentes de infertilidad masculina. Causas menos frecuentes son las disfunciones sexuales, trastornos endocrinos y efectos adversos de medicamentos. Los tratamientos para estas patologías han sido efectivos en la mayoría de los casos, permitiendo a un importante número de parejas concebir en forma espontánea. Si esto no es posible, las parejas pueden recurrir a técnicas de reproducción asistida de baja complejidad, tales como la Inseminación Intrauterina. Y sólo en aquellos casos con problemas más severos recurriremos a técnicas de reproducción de alta complejidad como por ejemplo el ICSI (Inyección Intracitoplasmática de Espermatozoides). Importantes progresos en el área de la Microcirugía permiten no sólo reparar la vía seminal en muchos casos, sino también recuperar espermatozoides de pacientes con atrofia testicular. En los últimos años, junto con el ICSI, han sido una importante contribución.

Research paper thumbnail of 1598: The Effect of the type of Azoospermia(Obstructive Vs Secretory) on the Results of Intra Cytoplasmatic Sperm Injection(Icsi)

Journal of Urology, 2004

THE JOURNAL OF UROLOGY® RESULTS: 78 patients underwent 83 varicocele repairs. Indications for var... more THE JOURNAL OF UROLOGY® RESULTS: 78 patients underwent 83 varicocele repairs. Indications for varicocele repair included a significant testicular size discrepancy in 73 patients, pain in 2 patients, or patient unwillingness to undergo observation in 2 patients. Patient age ranged from l1.8 to 21.5 years old. Median follow-up was 2.8 years (range 0.17 years to 9.8 years). Recurrent or persistent varicoceles were noted in 1.2% of patients. Complications consisted of cord hematomas in 2 patients. No post-operative hydroceles developed for a total complication rate of 3.4%. Fortyfour patients had post-operative testicular volume measurements of which 39 patients demonstrated an increase in ipsilateral testis size and 5 patients had no decrease in ipsilateral testis size. CONCLUSIONS: The microsurgical subinguinal approach is an extremely effective method of varicocele repair. Recurrence rates are lower than historical recurrence rates for traditional inguinal or retroperitoneal approaches. The use of the operative microscope allows for lymphatic preservation, which likely leads to the rarity of post-operative hydroceles. This approach should be considered as the initial approach for adolescent varicocele Source of Funding: None

Research paper thumbnail of 1386: Intraprostatic Injection of Botulinum Toxin in the Treatment of Symptomatic LUTS, Including Sequential Mris For Accurate Changes in Size of the Prostate

Journal of Urology, 2005

INTRODUCTION AND OBJECTIVE: The relationship between bladder outlet obstruction (BOO) due to beni... more INTRODUCTION AND OBJECTIVE: The relationship between bladder outlet obstruction (BOO) due to benign prostate hyperplasia and sexual dysfunction is of considerable current interest. The influence of surgical treatment of BOO on sexual dysfunction is uncertain and available evidence is conflicting. Transurethral resection of the prostate (TURP) is known to cause retrograde ejaculation, but its effect on erectile function is still discussed controversially. In our study we prospectively investigated the influence of TURP on erectile and ejaculatory function. METHODS: The presented data have been collected by the 'Outcome Association', a quality control instrument in the Swiss healthcare system. From January 2000 to August 2003 1190 patients scheduled for TURPin 10 hospitals in the Canton Zurich were prospectively assessed. A questionnaire including the sexual function domain of the Danish prostatic symptom score (DAN-PSS-Sex) and a question on general sexual activity was mailed out to the patients prior to their hospitalization as well as 4 months after surgery. DAN-PSS-Sex scores before and after TURP were compared using Wilcoxon signed ranks test (level of significance p<0.05). RESULTS: Preoperatively questionnaires of 839 patients were returned and deemed evaluable. Mean patient age was 69 years (range 43 to 91 years). 228 patients (27%) stated that they were still sexually active. Postoperatively 405 questionnaires were returned and evaluable for analysis. Therein I 06 patients (26%) declared that they were sexually active. In patients with 2 evaluable questionnaires the mean erectile function score increased (worsened) insignificantly from 0.853 to 0.911 (p=0.2). When this score was multiplied with the respective bother score, however, an almost significant decrease from 1.774 to 1.553 (p=0.05) resulted. Mean ejaculatory function scores increased from 1.063 to 2.239 (p<O.OOOI). Also after multiplication with the bother score the increase from 1.404 to 2.673 remained highly significant (p<O.OOO I). CONCLUSIONS: The results of our prospective study confirm that only about one out of four patients undergoing TURP is still sexually active and that the surgery has no influence on this ratio. Additionally, they show that TURP has no negative influence on the quality of erections, it even seems to improve the rate of bothersome erectile dysfunction. The loss of ejaculatory function, however, is not only significant, it is also associated with considerable bother.

Research paper thumbnail of 827 Development of convective water vapor therapy (steam) for focal therapy of prostate cancer. In vivo treatment and immediate radical prostatectomy

European Urology Supplements, 2015

Research paper thumbnail of Intrauterine insemination: critical analysis of a therapeutic procedure

Human Reproduction, 1992

Donor intrauterine insemination with washed spermatozoa (fresh semen) was performed in 36 women (... more Donor intrauterine insemination with washed spermatozoa (fresh semen) was performed in 36 women (63 cycles) whose husbands had azoospermia due to primary or secondary testicular failure. Simultaneously a control group of 76 couples (156 cycles) with proven fertility, who had recently discontinued mechanical non-hormonal contraception, were encouraged to have sexual intercourse during the fertile period. The age of the women was similar in both groups and the timing criteria were also similar. The pregnancy rate per woman was 50% in the donor insemination group and 47.4% in the control group (difference not significant). The pregnancy rate per cycle was 28.6% in the artificial insemination group and 23.1% in the control, natural insemination group (difference not significant). The number of artificial or natural insemination cycles required to achieve pregnancy was similar in the study and control groups. This study suggests that when the inseminating spermatozoa and female partner are normal, as occurs in the donor insemination group, intrauterine insemination is as efficient as natural insemination in achieving pregnancy but is not more successful.

Research paper thumbnail of Fertilization rate in couples with unexplained infertility

Human Reproduction, 1992

A group of 24 couples with unexplained infertility was scheduled for in-vitro fertilization and t... more A group of 24 couples with unexplained infertility was scheduled for in-vitro fertilization and tubal embryo transfer between May 1989 and September 1990. In the same period, in-vitro fertilization and intrauterine transfer of embryos was planned in a control group of 44 women with tubal infertility. The mean age and duration of infertility were similar in both groups and the same scheme of ovarian stimulation was used. No statistically significant difference was obtained comparing oestradiol levels and numbers of mature oocytes retrieved between the group of patients with unexplained infertility and those with tubal infertility. The fertilization rate of the oocytes obtained from women with unexplained infertility (60.4%) was significantly lower (P less than 0.001) than that of the oocytes obtained from patients with tubal infertility (87.3%). There was no statistically significant difference in the cleavage rates between patients with unexplained infertility and those with tubal infertility. It is concluded that lack of fertilization is an unexplored cause of infertility in couples with unexplained infertility.

Research paper thumbnail of 534 The effect of the type of azoospermia (obstructive vs. secretory) on the results of intra cytoplasmatic sperm injection (ICSI)

European Urology Supplements, 2004

Research paper thumbnail of The role of the epididymis in human infertility

Journal of reproduction and fertility. Supplement, 1998

This review describes the role of the epididymis in human infertility, by analysing the results o... more This review describes the role of the epididymis in human infertility, by analysing the results of epididymovasostomies which confirm that the more distal the site of obstruction the greater the chance of fertility. The use of epididymal spermatozoa for in vitro fertilization (IVF) yielded poor results in contrast to intracytoplasmic sperm injection using either epididymal or testicular spermatozoa. The nature of the pathology causing obstructive azoospermia is examined reviewing in particular the possible role of mercury toxicity in Young's syndrome. This review describes the results of studies that show that the level of obstruction within the epididymis is correlated with the presence of sperm antibodies and distal obstructions are associated with the presence of sperm antibodies. The demonstration that necrozoospermia decreases with increased sperm transport through the epididymis, when combined with the observation of normal testicular sperm morphology, represents the basis...

Research paper thumbnail of UP.69: Polymorphism of CYP1a1 MSP1 and Mortality in Patients with Prostatic Cancer: Seven-Year Follow-Up

Urology, 2008

From our patients, 41% received neoadjuvant hormonotherapy for prostate downsizing. The pre-impla... more From our patients, 41% received neoadjuvant hormonotherapy for prostate downsizing. The pre-implant ultrasound (US)based prostate volume was more than 36 cc in 78 patients and pre-implant international prostate symptom scores (IPSS) were more than 16 in 39 patients. All patients received ␣ 1-blockers before and throughout at least 60 days post-treatment. The follow-up ranged between 3 and 84 months (median 32.4). The clinical and treatment-related factors were evaluated for the need for catheterization owing to urinary retention. Results: Twenty-four (9%) patients required catheterization because of urinary retention. Median time to retention onset was 2 days (range 1-7 days) after implantation. In 19 of those patients, the prostate size was more than 35cc and the IPSS was more than 15. In all those patients, the number of needles were more than 20. Seventeen catheterized patients were successfully relieved from their catheter by nonsurgical means (a1-blockers plus anti-inflamatory) and seven underwent minimal transurethral resection of the prostate (TUR-P) not earlier than 7 months postimplant. Postoperatively there was no TUR-P-related incontinence. From the potent patients preimplantation, 63% remained unchangeable at the end of the first year and 56% after the second year. Conclusions: Our data suggest that preimplant US-based prostate volume, IPSS and the number of the needles are the strongest predictors for catheterization. Catheterized patients who are refractory to medical therapy can safely undergo a minimal TUR-P. The incidence of impotence also increases after the second year of implantation.

Research paper thumbnail of SCHU-49: Electrochemical Ablation of the Prostate: A Feasibility Study for the Treatment of Prostate Cancer and Benign Prostatic Hyperplasia

Urology, 2008

obesity and the diagnosis of PC (pϭ0.28 and 0.96 respectively). Out of the total number of patien... more obesity and the diagnosis of PC (pϭ0.28 and 0.96 respectively). Out of the total number of patients with PC (nϭ397) no association was found between the BMI (overweight and obesity) and PSA level (pϭ0.11 and 0.55), prostate volume (pϭ0.62 and 0.08) and Gleason score greater than 7 (pϭ0.77 and 0.98). Conclusion: In this series, there was no association between BMI and PC. The only factor that shows a trend is that obese patients have greater prostate volumes.

Research paper thumbnail of SCHU-48: Impact of Body Mass Index in Patients Undergoing Transrectal Biopsy for Prostate Cancer Screening

Research paper thumbnail of In Vivo Temperature Mapping of Prostate during Treatment with TherMatrx TMx-2000 Device: Heat Field and MRI Determinations of Necrotic Lesions

Journal of Endourology, 2005

The effectiveness of any thermotherapy device is determined by the temperatures created and how l... more The effectiveness of any thermotherapy device is determined by the temperatures created and how long they are applied. Understanding the heating characteristics of a thermotherapy device is vital to its correct implementation. Interstitial temperature mapping was used to determine the heat field created within the prostate by the TherMatrx TMx-2000 transurethral microwave thermotherapy (TUMT) device. Gadolinium-enhanced MRI was used to determine the extent, type, and pattern of coagulation necrosis caused by TUMT. Interstitial temperature mapping was performed during treatment in five patients with benign prostatic hyperplasia using 24 temperature sensors inserted through the perineum and arrayed throughout the prostate under ultrasound and X-ray guidance. Gadolinium-enhanced MRI scans were performed on all patients 1 week after treatment. Interstitial temperature mapping found the heat field created to peak at the urethral surface near the central part of the catheter antenna. Temperatures decreased at consistent rates of 1 to 1.4 degrees C/mm radially and 0.1 to 0.5 degrees C/mm longitudinally from the peak area. Gadolinium-enhanced MRI showed minimal dispersed necrosis and only in the periurethral area. The TMx-2000 can create temperatures &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;45 degrees C in areas 3 to 4 mm from the antenna. However, the heat pattern and protocol of the TMx-2000 produce necrosis-generating conditions only within a few millimeters of the urethra.

Research paper thumbnail of Expresión y actividad de proteínas de multirresistencia a drogas (MDR) en líneas celulares de cáncer de próstata; Expression and activity of multidrug resistance …

Rev. chil. …, 2010

Resumo: Introducción: Nuestro grupo ha reportado previamente una asociación entre sensibilidad a ... more Resumo: Introducción: Nuestro grupo ha reportado previamente una asociación entre sensibilidad a quimioterapia y la expresión de proteínas MDR (P-Gp y MRP1) en líneas celulares y cultivos primarios de cáncer de próstata, quedando por estudiar la actividad ...

Research paper thumbnail of Pharmacoperone IN3 enhances the apoptotic effect of leuprolide in prostate cancer cells by increasing the gonadotropin-releasing hormone receptor in the cell membrane

Anti-Cancer Drugs, 2012

Gonadotropin-releasing hormone (GnRH) agonists are widely used for the treatment of advanced pros... more Gonadotropin-releasing hormone (GnRH) agonists are widely used for the treatment of advanced prostate cancer (PCa). Agonists activate the GnRH receptor (GnRH-R), triggering apoptosis in PCa cells. In gonadotropes, the amount of GnRH-R in the plasma membrane is regulated by protein folding and endoplasmic reticulum retention, mechanisms that can be overcome by the pharmacoperone IN3. Our aim was to describe the intracellular distribution of GnRH-R in PCa cells and its relation to response to GnRH analog treatments. The expressions of GnRH-R in PCa biopsies were evaluated by immunohistochemistry and the intracellular distribution was determined by immunofluorescence in primary cell cultures from human PCa samples. Cultured cells were pretreated with IN3 and then with leuprolide. Cell survival was evaluated by 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) thiazolyl blue formazan and cell cycle and apoptosis by flow cytometry. We observed that the expression of GnRH-R decreased according to malignant progression. Most GnRH-R are located inside the cell, colocalizing with endoplasmic reticulum markers. The treatment with IN3 decreased cellular GnRH-R retention, increasing plasma membrane expression in approximately 60%. Pretreatment with IN3 decreased PCa cell survival compared with leuprolide-alone treatment, primarily because of an increase in apoptosis. We conclude that the response of PCa cells to leuprolide is related to the amount of GnRH-R in the plasma membrane. Therefore, pretreatment evaluation of the amount of these receptors may be a predictor of the outcome of leuprolide treatment in PCa patients. Assessment of systemic IN3 effect would be necessary to determine its utility as an adjuvant treatment in hormone-resistant tumors. Anti-Cancer Drugs

Research paper thumbnail of Male Factor Infertility Outcomes Using Magnetic Activated Cell Sorting in Intra Citoplasmatic Sperm Injection Cycles

Andrology-Open Access, 2016

Sperm DNA fragmentation can have negative consequences in clinical outcomes of couples undergoing... more Sperm DNA fragmentation can have negative consequences in clinical outcomes of couples undergoing Assisted Reproductive Technologies (ART). Sperm separation techniques are an important step in sperm selection for ART. The Magnetic Activated Cell Sorting (MACS) is a novel method that separates sperm by density gradient and molecular filtration to remove apoptotic sperm, which is associated to DNA damage. A decrease of DNA sperm fragmentation could improve ART outcomes. The main aim of this study was to assess the effect of MACS on fertilization, embryo development, implantation, clinical pregnancy and miscarriage rates, in couples undergoing intra cytoplasmic sperm injection (ICSI). Semen samples from 284 patients were divided in two groups; study group (n = 63) and control group (n = 221), analyzed by embryo transfer day (Day 3: ETD3 and day 5: ETD5) and male factor patients. Density gradients followed by MACS were used as sperm preparation method in the study group, while Swim up was the method used in the control group. Similar results were obtained between both groups for all parameters: fertilization rate of 77.18% versus 75.28%; blastulation rate of 46.66% versus 48.69%; implantation rate of 40.35% versus 35.52%; clinical pregnancy rate of 61.81% versus 59.31% and miscarriage rate of 2.94% versus 7.37%. However, statistical significant differences were found for implantation rate (study group 55.0% and control group 35.43%, p = 0.0138) in day 5 embryo transfers (ETD5). MACS technology does not improve general outcomes; however, it showed better results for ETD5. Further studies are required to identify real improvements in extended embryo culture in male infertility.

Research paper thumbnail of Membrane translocation and activation of GnRH receptor sensitize prostate cancer cells to radiation

International Journal of Radiation Biology, 2021

Abstract Background GnRH analogs are widely used as neoadjuvant agents for radiotherapy in prosta... more Abstract Background GnRH analogs are widely used as neoadjuvant agents for radiotherapy in prostate cancer (PCa) patients, with well-documented effects in reducing tumor bulk and increasing progression-free survival. GnRH analogs act locally in the prostate by triggering apoptosis of PCa cells via activation of the GnRH receptor (GnRHR). During PCa progression, the distribution of GnRHR within the cell is altered, with reduced expression in the cell membrane and remaining sequestered in the endoplasmic reticulum. Pharmacoperone IN3 is able to relocalize GnRHR to the cell membrane. The aim of this study was to evaluate the effect of radiation on PCa cells pretreated with leuprolide, alone or in combination with IN3, as radiosensitizers. Material and methods PC3 and human PCa primary cell cultures were treated with IN3 for 24 h, followed by different doses of leuprolide for 48 h and, finally, single doses of radiation (3, 6, and 9 Gy). After radiation, cell survival, apoptosis, cell cycle distribution, and colony growth were evaluated. Results Radiation reduced cell survival and increased apoptosis in a dose-dependent manner. This effect was also directly related to leuprolide concentration. Pretreatment with IN3 enhanced apoptosis and decreased cell survival, also observing a higher proportion of cells arrested in G2. Conclusion Neoadjuvant leuprolide increases radiation-mediated apoptosis of PCa cells. This effect was enhanced by pretreatment with pharmacoperone IN3. Clinical use of IN3 as a radiosensitizer combined with androgen deprivation therapy to improve survival of patients with PCa remains to be evaluated.

Research paper thumbnail of Effect of GnRH analogs on the expression of TrkA and p75 neurotrophin receptors in primary cell cultures from human prostate adenocarcinoma

The Prostate, 2005

BACKGROUND. GnRH analogs have antiproliferative and/or apoptotic effects on prostate cancer cells... more BACKGROUND. GnRH analogs have antiproliferative and/or apoptotic effects on prostate cancer cells. Also, neurotrophin receptors TrkA and p75 have been reported in normal prostate suggesting a role in the gland growth control. In prostate cancer, TrkA receptors seem to be overexpressed and p75 receptors show a decreased expression. These changes in neurotrophin receptors may be related with unbalanced growth in malignant cells. In the present study we investigate the effects of GnRH analogs (leuprolide and cetrorelix) on the expression of TrkA and p75 neurotrophin receptors in primary cultures of human prostate cancer cells. METHODS. Tissue was obtained from radical prostatectomies due to prostate adenocarcinoma. Cells were isolated after sequential enzyme digestion and cultured in defined media. Nerve growth factor (NGF) receptors in untreated cultures were estimated by immunofluorescence. Cultures were treated with leuprolide (agonist) or cetrorelix (antagonist) and expression of TrkA and p75 receptors were evaluated by semi quantitative RT-PCR (polymerase chain reaction) and western blot. Cell proliferation was estimated by MTT method and apoptosis through COMET assay. RESULTS. Both leuprolide and cetrorelix induced a significant increase in p75 receptor gene and protein expression at a concentration that induce apoptosis and decrease proliferation. TrkA receptors showed no changes in presence of GnRH analogs. CONCLUSIONS. GnRH analogs, leuprolide, and cetrorelix, change the ratio between neurotrophin receptors TrkA and p75 by increasing gene and protein expression of p75 receptor. Considering that TrkA receptor is related with proliferation and p75 with apoptosis, we suggest that our findings may explain, in part, the effect of GnRH analogs on prostate cancer growth.

Research paper thumbnail of SCHU-48: Impact of Body Mass Index in Patients Undergoing Transrectal Biopsy for Prostate Cancer Screening

Research paper thumbnail of Secretion of Glycosidases in Human Epididymal Cell Cultures

Archives of Andrology, 2000

The dynamics of glycosidase secretion was evaluated in human epididymal cell culture. Epithelial ... more The dynamics of glycosidase secretion was evaluated in human epididymal cell culture. Epithelial cells from caput, corpus, and cauda epididymis were isolated from tissue obtained from patients undergoing therapeutic orchidectomy due to prostatic carcinoma. The activities of a-glucosidase, N-acetylglucosaminidase, b-glucuronidase, and a-mannosidase were analyzed in conditioned culture media. Glycosidase activity was significantly higher in corpus and/or cauda than in caput epididymis. There was a time-dependent increase in enzyme activities that was maximal between 10 and 14 days of culture in all epididymal regions. Epididymal glycosidases are secreted by cultured epithelial cell from human epididymis with an increase toward the distal regions of this organ, which may be related to the dynamics of sperm maturation. Cultures from different epididymal regions may represent a valuable tool to study of human epididymal function.

Research paper thumbnail of Androgen regulation of glycosidase secretion in epithelial cell cultures from human epididymis

Human Reproduction, Jun 1, 1999

The human epididymis and its secretions actively promote sperm fertilizing capacity and provide p... more The human epididymis and its secretions actively promote sperm fertilizing capacity and provide protection for spermatozoa against harmful influences. Among epididymal secretions, glycosidases have been recently studied and associated with molecular changes on the sperm surface. In the present work, we studied the influence of different concentrations of testosterone, dihydrotestosterone and cyproterone acetate on the secretion of α-glucosidase, Nacetyl-glucosaminidase, β-glucuronidase and α-mannosidase by isolated and cultured epithelial cells from human caput, corpus and cauda epididymides. Cell cultures were obtained from aggregates of isolated tubule fragments plated on extracellular matrix-covered multi-well plates. Activities of the glycosidases were measured in conditioned culture media and were higher in the distal regions of the epididymis. Testosterone and dihydrotestosterone significantly increase the enzyme secretion in a concentrationdependent manner. This increase was higher in corpus and/or cauda than in caput epididymis. Cyproterone acetate caused a dose-dependent decrease in glycosidase secretion in cultures from all epididymal regions. It is concluded that the secretion of epididymal glycosidases is regulated by androgen, being stimulated by dihydrotestosterone and testosterone and inhibited by the androgen antagonist cyproterone acetate.

Research paper thumbnail of Infertilidad masculina

Revista Médica Clínica Las Condes, May 1, 2010

RESUMEN Se estima que aproximadamente un 15% de las parejas son incapaces de concebir luego de un... more RESUMEN Se estima que aproximadamente un 15% de las parejas son incapaces de concebir luego de un año de relaciones sexuales no protegidas; 30% son debidas a factor femenino y 30% a factor masculino. El 40% restante es de causa mixta. La evaluación inicial de rutina en el varón (que incluye una detallada historia clínica, examen físico y test básicos como perfil hormonal y análisis seminal) es por lo tanto esencial para la mejoría de su fertilidad. El varicocele, criptorquidia no tratada y las infecciones del tracto urogenital son las causas identificables más frecuentes de infertilidad masculina. Causas menos frecuentes son las disfunciones sexuales, trastornos endocrinos y efectos adversos de medicamentos. Los tratamientos para estas patologías han sido efectivos en la mayoría de los casos, permitiendo a un importante número de parejas concebir en forma espontánea. Si esto no es posible, las parejas pueden recurrir a técnicas de reproducción asistida de baja complejidad, tales como la Inseminación Intrauterina. Y sólo en aquellos casos con problemas más severos recurriremos a técnicas de reproducción de alta complejidad como por ejemplo el ICSI (Inyección Intracitoplasmática de Espermatozoides). Importantes progresos en el área de la Microcirugía permiten no sólo reparar la vía seminal en muchos casos, sino también recuperar espermatozoides de pacientes con atrofia testicular. En los últimos años, junto con el ICSI, han sido una importante contribución.

Research paper thumbnail of 1598: The Effect of the type of Azoospermia(Obstructive Vs Secretory) on the Results of Intra Cytoplasmatic Sperm Injection(Icsi)

Journal of Urology, 2004

THE JOURNAL OF UROLOGY® RESULTS: 78 patients underwent 83 varicocele repairs. Indications for var... more THE JOURNAL OF UROLOGY® RESULTS: 78 patients underwent 83 varicocele repairs. Indications for varicocele repair included a significant testicular size discrepancy in 73 patients, pain in 2 patients, or patient unwillingness to undergo observation in 2 patients. Patient age ranged from l1.8 to 21.5 years old. Median follow-up was 2.8 years (range 0.17 years to 9.8 years). Recurrent or persistent varicoceles were noted in 1.2% of patients. Complications consisted of cord hematomas in 2 patients. No post-operative hydroceles developed for a total complication rate of 3.4%. Fortyfour patients had post-operative testicular volume measurements of which 39 patients demonstrated an increase in ipsilateral testis size and 5 patients had no decrease in ipsilateral testis size. CONCLUSIONS: The microsurgical subinguinal approach is an extremely effective method of varicocele repair. Recurrence rates are lower than historical recurrence rates for traditional inguinal or retroperitoneal approaches. The use of the operative microscope allows for lymphatic preservation, which likely leads to the rarity of post-operative hydroceles. This approach should be considered as the initial approach for adolescent varicocele Source of Funding: None

Research paper thumbnail of 1386: Intraprostatic Injection of Botulinum Toxin in the Treatment of Symptomatic LUTS, Including Sequential Mris For Accurate Changes in Size of the Prostate

Journal of Urology, 2005

INTRODUCTION AND OBJECTIVE: The relationship between bladder outlet obstruction (BOO) due to beni... more INTRODUCTION AND OBJECTIVE: The relationship between bladder outlet obstruction (BOO) due to benign prostate hyperplasia and sexual dysfunction is of considerable current interest. The influence of surgical treatment of BOO on sexual dysfunction is uncertain and available evidence is conflicting. Transurethral resection of the prostate (TURP) is known to cause retrograde ejaculation, but its effect on erectile function is still discussed controversially. In our study we prospectively investigated the influence of TURP on erectile and ejaculatory function. METHODS: The presented data have been collected by the 'Outcome Association', a quality control instrument in the Swiss healthcare system. From January 2000 to August 2003 1190 patients scheduled for TURPin 10 hospitals in the Canton Zurich were prospectively assessed. A questionnaire including the sexual function domain of the Danish prostatic symptom score (DAN-PSS-Sex) and a question on general sexual activity was mailed out to the patients prior to their hospitalization as well as 4 months after surgery. DAN-PSS-Sex scores before and after TURP were compared using Wilcoxon signed ranks test (level of significance p<0.05). RESULTS: Preoperatively questionnaires of 839 patients were returned and deemed evaluable. Mean patient age was 69 years (range 43 to 91 years). 228 patients (27%) stated that they were still sexually active. Postoperatively 405 questionnaires were returned and evaluable for analysis. Therein I 06 patients (26%) declared that they were sexually active. In patients with 2 evaluable questionnaires the mean erectile function score increased (worsened) insignificantly from 0.853 to 0.911 (p=0.2). When this score was multiplied with the respective bother score, however, an almost significant decrease from 1.774 to 1.553 (p=0.05) resulted. Mean ejaculatory function scores increased from 1.063 to 2.239 (p<O.OOOI). Also after multiplication with the bother score the increase from 1.404 to 2.673 remained highly significant (p<O.OOO I). CONCLUSIONS: The results of our prospective study confirm that only about one out of four patients undergoing TURP is still sexually active and that the surgery has no influence on this ratio. Additionally, they show that TURP has no negative influence on the quality of erections, it even seems to improve the rate of bothersome erectile dysfunction. The loss of ejaculatory function, however, is not only significant, it is also associated with considerable bother.

Research paper thumbnail of 827 Development of convective water vapor therapy (steam) for focal therapy of prostate cancer. In vivo treatment and immediate radical prostatectomy

European Urology Supplements, 2015

Research paper thumbnail of Intrauterine insemination: critical analysis of a therapeutic procedure

Human Reproduction, 1992

Donor intrauterine insemination with washed spermatozoa (fresh semen) was performed in 36 women (... more Donor intrauterine insemination with washed spermatozoa (fresh semen) was performed in 36 women (63 cycles) whose husbands had azoospermia due to primary or secondary testicular failure. Simultaneously a control group of 76 couples (156 cycles) with proven fertility, who had recently discontinued mechanical non-hormonal contraception, were encouraged to have sexual intercourse during the fertile period. The age of the women was similar in both groups and the timing criteria were also similar. The pregnancy rate per woman was 50% in the donor insemination group and 47.4% in the control group (difference not significant). The pregnancy rate per cycle was 28.6% in the artificial insemination group and 23.1% in the control, natural insemination group (difference not significant). The number of artificial or natural insemination cycles required to achieve pregnancy was similar in the study and control groups. This study suggests that when the inseminating spermatozoa and female partner are normal, as occurs in the donor insemination group, intrauterine insemination is as efficient as natural insemination in achieving pregnancy but is not more successful.

Research paper thumbnail of Fertilization rate in couples with unexplained infertility

Human Reproduction, 1992

A group of 24 couples with unexplained infertility was scheduled for in-vitro fertilization and t... more A group of 24 couples with unexplained infertility was scheduled for in-vitro fertilization and tubal embryo transfer between May 1989 and September 1990. In the same period, in-vitro fertilization and intrauterine transfer of embryos was planned in a control group of 44 women with tubal infertility. The mean age and duration of infertility were similar in both groups and the same scheme of ovarian stimulation was used. No statistically significant difference was obtained comparing oestradiol levels and numbers of mature oocytes retrieved between the group of patients with unexplained infertility and those with tubal infertility. The fertilization rate of the oocytes obtained from women with unexplained infertility (60.4%) was significantly lower (P less than 0.001) than that of the oocytes obtained from patients with tubal infertility (87.3%). There was no statistically significant difference in the cleavage rates between patients with unexplained infertility and those with tubal infertility. It is concluded that lack of fertilization is an unexplored cause of infertility in couples with unexplained infertility.

Research paper thumbnail of 534 The effect of the type of azoospermia (obstructive vs. secretory) on the results of intra cytoplasmatic sperm injection (ICSI)

European Urology Supplements, 2004

Research paper thumbnail of The role of the epididymis in human infertility

Journal of reproduction and fertility. Supplement, 1998

This review describes the role of the epididymis in human infertility, by analysing the results o... more This review describes the role of the epididymis in human infertility, by analysing the results of epididymovasostomies which confirm that the more distal the site of obstruction the greater the chance of fertility. The use of epididymal spermatozoa for in vitro fertilization (IVF) yielded poor results in contrast to intracytoplasmic sperm injection using either epididymal or testicular spermatozoa. The nature of the pathology causing obstructive azoospermia is examined reviewing in particular the possible role of mercury toxicity in Young's syndrome. This review describes the results of studies that show that the level of obstruction within the epididymis is correlated with the presence of sperm antibodies and distal obstructions are associated with the presence of sperm antibodies. The demonstration that necrozoospermia decreases with increased sperm transport through the epididymis, when combined with the observation of normal testicular sperm morphology, represents the basis...

Research paper thumbnail of UP.69: Polymorphism of CYP1a1 MSP1 and Mortality in Patients with Prostatic Cancer: Seven-Year Follow-Up

Urology, 2008

From our patients, 41% received neoadjuvant hormonotherapy for prostate downsizing. The pre-impla... more From our patients, 41% received neoadjuvant hormonotherapy for prostate downsizing. The pre-implant ultrasound (US)based prostate volume was more than 36 cc in 78 patients and pre-implant international prostate symptom scores (IPSS) were more than 16 in 39 patients. All patients received ␣ 1-blockers before and throughout at least 60 days post-treatment. The follow-up ranged between 3 and 84 months (median 32.4). The clinical and treatment-related factors were evaluated for the need for catheterization owing to urinary retention. Results: Twenty-four (9%) patients required catheterization because of urinary retention. Median time to retention onset was 2 days (range 1-7 days) after implantation. In 19 of those patients, the prostate size was more than 35cc and the IPSS was more than 15. In all those patients, the number of needles were more than 20. Seventeen catheterized patients were successfully relieved from their catheter by nonsurgical means (a1-blockers plus anti-inflamatory) and seven underwent minimal transurethral resection of the prostate (TUR-P) not earlier than 7 months postimplant. Postoperatively there was no TUR-P-related incontinence. From the potent patients preimplantation, 63% remained unchangeable at the end of the first year and 56% after the second year. Conclusions: Our data suggest that preimplant US-based prostate volume, IPSS and the number of the needles are the strongest predictors for catheterization. Catheterized patients who are refractory to medical therapy can safely undergo a minimal TUR-P. The incidence of impotence also increases after the second year of implantation.

Research paper thumbnail of SCHU-49: Electrochemical Ablation of the Prostate: A Feasibility Study for the Treatment of Prostate Cancer and Benign Prostatic Hyperplasia

Urology, 2008

obesity and the diagnosis of PC (pϭ0.28 and 0.96 respectively). Out of the total number of patien... more obesity and the diagnosis of PC (pϭ0.28 and 0.96 respectively). Out of the total number of patients with PC (nϭ397) no association was found between the BMI (overweight and obesity) and PSA level (pϭ0.11 and 0.55), prostate volume (pϭ0.62 and 0.08) and Gleason score greater than 7 (pϭ0.77 and 0.98). Conclusion: In this series, there was no association between BMI and PC. The only factor that shows a trend is that obese patients have greater prostate volumes.

Research paper thumbnail of SCHU-48: Impact of Body Mass Index in Patients Undergoing Transrectal Biopsy for Prostate Cancer Screening

Research paper thumbnail of In Vivo Temperature Mapping of Prostate during Treatment with TherMatrx TMx-2000 Device: Heat Field and MRI Determinations of Necrotic Lesions

Journal of Endourology, 2005

The effectiveness of any thermotherapy device is determined by the temperatures created and how l... more The effectiveness of any thermotherapy device is determined by the temperatures created and how long they are applied. Understanding the heating characteristics of a thermotherapy device is vital to its correct implementation. Interstitial temperature mapping was used to determine the heat field created within the prostate by the TherMatrx TMx-2000 transurethral microwave thermotherapy (TUMT) device. Gadolinium-enhanced MRI was used to determine the extent, type, and pattern of coagulation necrosis caused by TUMT. Interstitial temperature mapping was performed during treatment in five patients with benign prostatic hyperplasia using 24 temperature sensors inserted through the perineum and arrayed throughout the prostate under ultrasound and X-ray guidance. Gadolinium-enhanced MRI scans were performed on all patients 1 week after treatment. Interstitial temperature mapping found the heat field created to peak at the urethral surface near the central part of the catheter antenna. Temperatures decreased at consistent rates of 1 to 1.4 degrees C/mm radially and 0.1 to 0.5 degrees C/mm longitudinally from the peak area. Gadolinium-enhanced MRI showed minimal dispersed necrosis and only in the periurethral area. The TMx-2000 can create temperatures &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;45 degrees C in areas 3 to 4 mm from the antenna. However, the heat pattern and protocol of the TMx-2000 produce necrosis-generating conditions only within a few millimeters of the urethra.

Research paper thumbnail of Expresión y actividad de proteínas de multirresistencia a drogas (MDR) en líneas celulares de cáncer de próstata; Expression and activity of multidrug resistance …

Rev. chil. …, 2010

Resumo: Introducción: Nuestro grupo ha reportado previamente una asociación entre sensibilidad a ... more Resumo: Introducción: Nuestro grupo ha reportado previamente una asociación entre sensibilidad a quimioterapia y la expresión de proteínas MDR (P-Gp y MRP1) en líneas celulares y cultivos primarios de cáncer de próstata, quedando por estudiar la actividad ...

Research paper thumbnail of Pharmacoperone IN3 enhances the apoptotic effect of leuprolide in prostate cancer cells by increasing the gonadotropin-releasing hormone receptor in the cell membrane

Anti-Cancer Drugs, 2012

Gonadotropin-releasing hormone (GnRH) agonists are widely used for the treatment of advanced pros... more Gonadotropin-releasing hormone (GnRH) agonists are widely used for the treatment of advanced prostate cancer (PCa). Agonists activate the GnRH receptor (GnRH-R), triggering apoptosis in PCa cells. In gonadotropes, the amount of GnRH-R in the plasma membrane is regulated by protein folding and endoplasmic reticulum retention, mechanisms that can be overcome by the pharmacoperone IN3. Our aim was to describe the intracellular distribution of GnRH-R in PCa cells and its relation to response to GnRH analog treatments. The expressions of GnRH-R in PCa biopsies were evaluated by immunohistochemistry and the intracellular distribution was determined by immunofluorescence in primary cell cultures from human PCa samples. Cultured cells were pretreated with IN3 and then with leuprolide. Cell survival was evaluated by 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) thiazolyl blue formazan and cell cycle and apoptosis by flow cytometry. We observed that the expression of GnRH-R decreased according to malignant progression. Most GnRH-R are located inside the cell, colocalizing with endoplasmic reticulum markers. The treatment with IN3 decreased cellular GnRH-R retention, increasing plasma membrane expression in approximately 60%. Pretreatment with IN3 decreased PCa cell survival compared with leuprolide-alone treatment, primarily because of an increase in apoptosis. We conclude that the response of PCa cells to leuprolide is related to the amount of GnRH-R in the plasma membrane. Therefore, pretreatment evaluation of the amount of these receptors may be a predictor of the outcome of leuprolide treatment in PCa patients. Assessment of systemic IN3 effect would be necessary to determine its utility as an adjuvant treatment in hormone-resistant tumors. Anti-Cancer Drugs

Research paper thumbnail of Male Factor Infertility Outcomes Using Magnetic Activated Cell Sorting in Intra Citoplasmatic Sperm Injection Cycles

Andrology-Open Access, 2016

Sperm DNA fragmentation can have negative consequences in clinical outcomes of couples undergoing... more Sperm DNA fragmentation can have negative consequences in clinical outcomes of couples undergoing Assisted Reproductive Technologies (ART). Sperm separation techniques are an important step in sperm selection for ART. The Magnetic Activated Cell Sorting (MACS) is a novel method that separates sperm by density gradient and molecular filtration to remove apoptotic sperm, which is associated to DNA damage. A decrease of DNA sperm fragmentation could improve ART outcomes. The main aim of this study was to assess the effect of MACS on fertilization, embryo development, implantation, clinical pregnancy and miscarriage rates, in couples undergoing intra cytoplasmic sperm injection (ICSI). Semen samples from 284 patients were divided in two groups; study group (n = 63) and control group (n = 221), analyzed by embryo transfer day (Day 3: ETD3 and day 5: ETD5) and male factor patients. Density gradients followed by MACS were used as sperm preparation method in the study group, while Swim up was the method used in the control group. Similar results were obtained between both groups for all parameters: fertilization rate of 77.18% versus 75.28%; blastulation rate of 46.66% versus 48.69%; implantation rate of 40.35% versus 35.52%; clinical pregnancy rate of 61.81% versus 59.31% and miscarriage rate of 2.94% versus 7.37%. However, statistical significant differences were found for implantation rate (study group 55.0% and control group 35.43%, p = 0.0138) in day 5 embryo transfers (ETD5). MACS technology does not improve general outcomes; however, it showed better results for ETD5. Further studies are required to identify real improvements in extended embryo culture in male infertility.

Research paper thumbnail of Membrane translocation and activation of GnRH receptor sensitize prostate cancer cells to radiation

International Journal of Radiation Biology, 2021

Abstract Background GnRH analogs are widely used as neoadjuvant agents for radiotherapy in prosta... more Abstract Background GnRH analogs are widely used as neoadjuvant agents for radiotherapy in prostate cancer (PCa) patients, with well-documented effects in reducing tumor bulk and increasing progression-free survival. GnRH analogs act locally in the prostate by triggering apoptosis of PCa cells via activation of the GnRH receptor (GnRHR). During PCa progression, the distribution of GnRHR within the cell is altered, with reduced expression in the cell membrane and remaining sequestered in the endoplasmic reticulum. Pharmacoperone IN3 is able to relocalize GnRHR to the cell membrane. The aim of this study was to evaluate the effect of radiation on PCa cells pretreated with leuprolide, alone or in combination with IN3, as radiosensitizers. Material and methods PC3 and human PCa primary cell cultures were treated with IN3 for 24 h, followed by different doses of leuprolide for 48 h and, finally, single doses of radiation (3, 6, and 9 Gy). After radiation, cell survival, apoptosis, cell cycle distribution, and colony growth were evaluated. Results Radiation reduced cell survival and increased apoptosis in a dose-dependent manner. This effect was also directly related to leuprolide concentration. Pretreatment with IN3 enhanced apoptosis and decreased cell survival, also observing a higher proportion of cells arrested in G2. Conclusion Neoadjuvant leuprolide increases radiation-mediated apoptosis of PCa cells. This effect was enhanced by pretreatment with pharmacoperone IN3. Clinical use of IN3 as a radiosensitizer combined with androgen deprivation therapy to improve survival of patients with PCa remains to be evaluated.