epidermal-growth-factor and cetrorelix

The intrafollicular levels of IGF-I and epidermal growth factor (EGF) were studied in women undergoing controlled ovarian hyperstimulation using the multidose GnRH-antagonist protocol or the long agonist protocol, in an attempt to elucidate whether GnRH-antagonists affect the levels of the two growth factors. The follicular fluid concentration of IGF-I, EGF, estradiol and progesterone were detected in 68 women undergoing ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI) cycles. There were no differences in intrafollicular concentrations of EGF and IGF-I in the two studied groups. Additionally, we found no correlation between the intrafollicular levels of IGF-I or EGF and the ICSI outcome. The intrafollicular levels of IGF-I were positively correlated with those of progesterone. In conclusion, the intrafollicular levels of IGF-I and EGF do not seem to be influenced by the stimulation protocol. The intrafollicular levels of both growth factors can not serve as prognostic markers for the ICSI outcome.

Topics: Adult; Epidermal Growth Factor; Estradiol; Female; Follicle Stimulating Hormone; Follicular Fluid; Gonadotropin-Releasing Hormone; Humans; Insulin-Like Growth Factor I; Menotropins; Ovulation Induction; Progesterone; Sperm Injections, Intracytoplasmic; Treatment Outcome; Triptorelin Pamoate

To determine the serum and intrafollicular concentrations of sex steroids, epidermal growth factor (EGF) and insulin like growth factor-1 (IGF-1) in women demonstrating poor response to ovarian stimulation with gonadotropins and GnRH antagonists, and to compare the results with age-matched women displaying normal ovarian response.. This is a prospective cross-sectional study conducted in a private IVF center. Forty-eight age-matched women producing 5 or fewer oocytes (poor responders) or 10 or more oocytes (normoresponders) at the end of controlled ovarian stimulation for assisted conception participated in the experiment. Gonadotropins and GnRH antagonists were used for ovarian stimulation, while ICSI was employed for assisted fertilization. Serum and follicular concentrations of FSH, LH and sex steroids (estradiol, progesterone and testosterone), and follicular concentrations of EGF and IGF-1 were assayed in both groups.. Serum and follicular levels of E(2) and progesterone were significantly lower in the poor responder group compared to the normoresponder group. Follicular level of testosterone was also lower in poor responders, but not to a level of statistical significance. The serum FSH level was higher in the poor responder group, but follicular levels of gonadotropins did not differ between the two groups. The follicular level of IGF-1 was significantly lower in poor responders. In contrast, the EGF concentration did not differ between the two groups.. Decreased levels of sex steroids in poor responder patients undergoing COH with GnRH antagonist, suggests that reduced IGF-1 expression acts as a modulator of impaired ovarian steroidogenesis.

Topics: Adult; Biomarkers; Cross-Sectional Studies; Epidermal Growth Factor; Estradiol; Female; Gonadotropin-Releasing Hormone; Gonadotropins, Pituitary; Hormone Antagonists; Humans; Insulin-Like Growth Factor I; Ovarian Follicle; Ovulation Induction; Progesterone; Prospective Studies; Sperm Injections, Intracytoplasmic; Testosterone; Treatment Outcome

Antagonists of growth hormone-releasing hormone (GHRH) could extend the duration of response of androgen sensitive prostate cancers to androgen deprivation.. We investigated the effect of new GHRH antagonists MZ-J-7-118 and MZ-J-7-138 and luteinizing hormone-releasing hormone (LHRH) antagonist Cetrorelix or castration on androgen sensitive MDA-PCa-2b and LuCaP-35 prostate cancer models xenografted into nude mice. Animals bearing androgen-independent LuCaP-35V prostatic cancer model were also treated with MZ-J-7-118.. Receptors for LHRH and GHRH were present in MDA-PCA-2b, LuCaP-35, and LuCaP-35V tumors. GHRH antagonists increased the inhibitory effect of surgical castration and LHRH antagonists on androgen sensitive MDA-PCa-2b and LuCaP-35 tumors. The time to relapse of androgen-dependent LuCaP-35 tumors was extended by GHRH antagonists. Growth of androgen-independent LuCaP-35V xenografts was also significantly inhibited by MZ-J-7-118. In MDA-PCa-2b tumors treatment with MZ-J-7-118 caused a significant decrease of VEGF and Cetrorelix or its combination with MZ-J-7-118 reduced EGF. The B(max) of EGF receptors was significantly reduced by Cetrorelix, MZ-J-7-118 and their combination.. Our findings suggest that the use of a combination of antagonists of GHRH and LHRH could improve the therapy for androgen sensitive prostate cancer. Antagonists of GHRH could be also considered for treatment of androgen-independent prostate cancers.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Drug Synergism; Epidermal Growth Factor; Gonadotropin-Releasing Hormone; Growth Hormone-Releasing Hormone; Hormone Antagonists; Humans; Insulin-Like Growth Factor I; Male; Mice; Mice, Nude; Neoplasms, Hormone-Dependent; Prostate-Specific Antigen; Prostatic Neoplasms; Sermorelin; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays

The objective of this study was to elucidate the effects of GnRH antagonist Cetrorelix on proliferation and apoptosis in human leiomyoma cells cultured in vitro. Isolated leiomyoma cells were subcultured in phenol red-free DMEM supplemented with 10% fetal bovine serum for 120 h and then stepped down to serum-free conditions in the presence or absence of graded concentrations of Cetrorelix (10(-5) to 10(-8) mol/liter) for 6 d. Cultured leiomyoma cells were used for semiquantitative RT-PCR, immunocytochemistry, Western blot analysis, and terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling assay. RT-PCR analysis revealed the presence of mRNAs encoding for GnRH receptor and epidermal growth factor (EGF) in cultured leiomyoma cells. The number of viable cultured leiomyoma cells was significantly (P < 0.01) decreased by treatment with Cetrorelix compared with untreated control cultures. Immunocytochemical examination demonstrated that treatment with Cetrorelix attenuated the expression of proliferating cell nuclear antigen (PCNA) and EGF in cultured leiomyoma cells. Western blot analysis revealed that treatment with 10(-5) mol/liter Cetrorelix significantly (P < 0.01) decreased PCNA expression. In addition, treatment with 10(-5) mol/liter Cetrorelix remarkably increased the terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling-positive rate and poly(ADP-ribose) polymerase expression at 24 h of treatment compared with untreated control cultures (P < 0.01). Furthermore, treatment with 10(-5) mol/liter Cetrorelix decreased immunoreactive EGF protein and EGF mRNA expression in cultured leiomyoma cells at 4 d of treatment. GnRH antagonist Cetrorelix may directly inhibit leiomyoma cell growth by down-regulating proliferation in association with a decrease in EGF mRNA expression and by up-regulating apoptosis in those cells.

Topics: Adult; Apoptosis; Base Sequence; Cell Survival; DNA Primers; Epidermal Growth Factor; Female; Gene Expression Regulation, Neoplastic; Gonadotropin-Releasing Hormone; Humans; Leiomyoma; Poly(ADP-ribose) Polymerases; Premenopause; Proliferating Cell Nuclear Antigen; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tumor Cells, Cultured; Uterine Neoplasms

Spontaneous and epidermal growth-factor-induced proliferation of human gynecological cancer cell lines is dose- and time-dependently reduced by treatment with the luteinizing hormone-releasing hormone (LHRH) agonist triptorelin and antagonist Cetrorelix. This antiproliferative activity is probably directly mediated through the LHRH receptors expressed by the tumor cells interacting with growth-factor-dependent mitogenic signal transduction. We have examined whether epidermal growth-factor (EGF)-induced expression of the early response gene c-fos is reduced by LHRH analogs.. Human endometrial (Ishikawa, Hec-1A), ovarian (EFO-21, EFO-27, SK-OV-3), and breast cancer cell lines (MCF-7) were rendered quiescent by incubation (72 h) in the absence of fetal calf serum and phenol red. This was followed by a 15-min incubation in the absence or presence of the LHRH agonist triptorelin (100 nM) or the antagonist Cetrorelix (100 nM) before the cells were stimulated for 10 min with EGF (100 nM). C-fos mRNA expression was determined by semi-quantitative RT-PCR using a synthetic DNA fragment as internal standard. C-Fos protein synthesis was determined by SDS-PAGE and semi-quantitative Western blotting.. In cells derived from endometrial and ovarian cancer, maximal c-fos mRNA expression (seven- to ninefold over basal level) was obtained 30 min after EGF stimulation. In the breast cancer cell line MCF-7 this effect was obtained 60 min after EGF treatment. In all of the lines expressing LHRH receptor, EGF-induced c-fos mRNA expression as well as c-Fos protein synthesis was dose-dependently reduced by treatment with LHRH agonists and antagonists. At 100 nM concentrations of the LHRH analogs, c-fos expression was reduced to baseline levels. No effect of LHRH analogs on EGF-induced c-fos expression was observed in the ovarian cancer cell line SK-OV-3, which does not express the LHRH receptor.. These results suggest that the binding of LHRH agonists and antagonists to their receptors inhibits the mitogenic signal transduction pathway of the EGF receptor in endometrial, ovarian, and breast cancer cell lines. The coupling of both signal transduction systems mediates the antiproliferative effect of LHRH analogs.

Topics: Antineoplastic Agents, Hormonal; Down-Regulation; Epidermal Growth Factor; Female; Gene Expression; Gene Expression Regulation, Neoplastic; Genes, fos; Genital Neoplasms, Female; Gonadotropin-Releasing Hormone; Hormone Antagonists; Humans; Luteolytic Agents; Proto-Oncogene Proteins c-fos; Receptors, LHRH; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Triptorelin Pamoate; Tumor Cells, Cultured

Using radioligand binding, RT-PCR, and Southern blot analyses, we evaluated whether agonist [D-Trp6]LH-RH and antagonist Cetrorelix could affect the levels of receptors for LH-RH and EGF and expression of mRNA for these receptors in DU-145 human androgen-independent prostate cancers xenografted into nude mice. Radioligand binding studies showed the presence of specific high affinity receptors for LH-RH and EGF in DU-145 prostate tumors. Cetrorelix, but not [D-Trp6]LH-RH significantly inhibited tumor growth. The concentration of LH-RH receptors was reduced by 22% (p<0. 05) and 67% (p<0.01) after 4 weeks of treatment with [D-Trp6]LH-RH and Cetrorelix respectively. The concentration of EGF receptors fell by 48% (p<0.05) in the [D-Trp6]LH-RH group, whereas Cetrorelix led to a 66% reduction (p<0.01). The expression of LH-RH and EGF receptor mRNA was investigated by RT-PCR analysis followed by Southern blotting. Densitometric analysis of the developed bands showed that the antagonist Cetrorelix decreased the expression of LH-RH receptor mRNA by 55% (p<0.01) compared to control group while the 20% reduction after treatment with the LH-RH agonist was non-significant. Treatment with [D-Trp6]LH-RH and Cetrorelix also reduced the expression of EGF receptor mRNA by 35% and 68% respectively (both, p<0.01) compared to control group. In conclusion, these data demonstrate that growth inhibition of DU-145 prostate tumors induced by prolonged administration of LH-RH antagonist Cetrorelix is accompanied by a marked decrease in the concentration of LH-RH and EGF receptors as well as in their mRNA levels.

Topics: Animals; Binding Sites; Blotting, Southern; Epidermal Growth Factor; ErbB Receptors; Gonadotropin-Releasing Hormone; Hormone Antagonists; Humans; Male; Mice; Mice, Nude; Neoplasm Transplantation; Neoplasms, Hormone-Dependent; Polymerase Chain Reaction; Prostatic Neoplasms; Radioligand Assay; Receptors, LHRH; RNA, Messenger; Transcription, Genetic; Transplantation, Heterologous; Triptorelin Pamoate; Tumor Cells, Cultured

Our objective was to study the direct action of luteinizing hormone-releasing hormone (LHRH) agonist buserelin and LHRH antagonist Cetrorelix (SB-75) on cell proliferation and differentiation in the rat ovarian follicle. Preovulatory follicles were isolated from PMSG-primed immature rats and incubated in the presence or absence of hCG (10 IU/ml), buserelin (10(-9)-10(-6) M) or Cetrorelix (10(-9)-10(-6) M) for 12 h in vitro. Buserelin induced meiotic maturation of the follicle-enclosed oocytes dose-dependently. The percentage of oocytes with germinal vesicle breakdown at 10(-6) M buserelin (73.3%) did not differ from that of hCG-treated control (73.3%). Buserelin also significantly stimulated prostaglandin E2 and progesterone production by follicles, but not estradiol production. Granulosa cells were obtained from the preovulatory follicles and cultured for 5 days. Epidermal growth factor (EGF) stimulated granulosa cell growth at concentrations of 1, 10 and 100 ng/ml. In contrast, both buserelin and Cetrorelix inhibited granulosa cell growth dose-dependently in the range of 10(-10)-10(-5) M, with Cetrorelix inducing a greater growth inhibition than buserelin. Electrophoretic analysis of genomic DNA extracted from granulosa cells treated with 10(-6) M concentration of either LHRH analog revealed a definitive ladder pattern of oligonucleosomal length DNA fragments characteristic of apoptosis. Western blotting detected that EGF-induced tyrosine phosphorylation was not affected by either analog. These results demonstrate that LHRH agonist and antagonist inhibit directly proliferation of granulosa cells through apoptosis, without interference with EGF receptor phosphorylation, whereas LHRH agonist stimulates cell differentiation in the preovulatory follicle.

Topics: Animals; Apoptosis; Buserelin; Cells, Cultured; Epidermal Growth Factor; Female; Gonadotropin-Releasing Hormone; Granulosa Cells; Organ Culture Techniques; Ovarian Follicle; Protein-Tyrosine Kinases; Rats; Rats, Wistar

The effects of treatment with the luteinizing hormone-releasing hormone (LH-RH) antagonist SB-75 and agonist [D-Trp6] LH-RH were investigated in Copenhagen rats bearing the anaplastic, androgen-independent Dunning R-3327-AT-1 prostatic adenocarcinoma implanted orthotopically into the ventral lobes of prostate glands. The LH-RH antagonist SB-75 and the LH-RH agonist [D-Trp6] LH-RH were administered from osmotic minipumps and the survival time of animals bearing this cancer was evaluated. Treatment with SB-75 and [D-Trp6] LH-RH significantly prolonged the mean survival time of rats by 4.1 days and 4.5 days, respectively. In cell cultures, proliferation of the AT-1 cell line was strongly inhibited by the antagonist SB-75, but only a moderate suppression of tumor cell growth in vitro was observed with the agonist [D-Trp6] LH-RH. Receptor assays on Dunning R-3327-AT-1 tumor membranes showed high-affinity binding sites for LH-RH, epidermal growth factor (EGF) and insulin-like growth factor-1 (IGF-1). Receptors for EGF were significantly down-regulated by treatment with SB-75. Therapy with SB-75 also decreased EGF levels in tumor tissue to non-detectable levels, as measured by specific RIA. Our results demonstrate that the LH-RH antagonist SB-75 and agonist [D-Trp6] LH-RH inhibit the growth of androgen-independent Dunning R-3327-AT-1 prostatic cancer in vivo and in vitro.

Topics: Androgens; Animals; Cell Division; Cell Membrane; DNA, Neoplasm; Epidermal Growth Factor; ErbB Receptors; Gonadotropin-Releasing Hormone; Insulin-Like Growth Factor I; Luteinizing Hormone; Male; Prostatic Neoplasms; Rats; Receptor, IGF Type 1; Triptorelin Pamoate

The results of several clinical trials using various luteinizing hormone-releasing hormone agonists for treatment of advanced breast cancer are encouraging. However, only about 30% of breast cancers are estrogen-dependent and can be treated by hormonal manipulation. New therapeutic approaches combining estrogen ablation therapy with other compounds must be explored. Various studies suggest that bombesin or gastrin-releasing peptide acts as an autocrine growth factor and may play a role in the initiation and progression of some cancers, including that of the breast.. Female athymic nude mice bearing xenografts of the MCF-7 MIII human breast cancer cell line were treated for 7 weeks with bombesin/gastrin-releasing peptide antagonist (D-Tpi6, Leu13 psi[CH2NH]-Leu14) bombesin(6-14) (RC-3095) injected subcutaneously daily at a dose of 20 micrograms and luteinizing hormone-releasing hormone antagonist SB-75 (Cetrorelix) administered biweekly in the form of microgranules releasing 45 micrograms/day.. After 2 weeks of treatment, a significant inhibition of tumor volume was observed in the groups treated with RC-3095 alone or in combination with SB-75 but not in those treated with SB-75 as a single agent. After 7 weeks, tumor growth as measured by tumor volume and percentage changes in tumor volume and tumor weight was greatly inhibited in all of the treated groups. Uterine and ovarian weights were reduced and serum luteinizing hormone levels decreased by administration of SB-75 alone or in combination with RC-3095. Histologically, a significant decrease in argyrophilic nucleolar organizer region count in tumor cell nuclei was observed in all of the treated groups, indicating a lower proliferation of these cells. High-affinity binding sites for bombesin were detected in cultured MCF-7 MIII cells. Chronic treatment with RC-3095 caused a significant down-regulation of epidermal growth factor receptors in tumor cell membranes, which might be related to tumor inhibition. In studies in vitro, SB-75 inhibited proliferation of MCF-7 cells in culture but not proliferation of MCF-7 MIII cells.. Because previously we demonstrated that RC-3095 inhibits the proliferation of MCF-7 MIII cells in vitro, it appears that the major antitumoral effect of RC-3095 on the MCF-7 MIII cancer line is direct, whereas that of SB-75 is indirect, and that it is mediated by suppression of the pituitary-gonadal axis. In view of its immediate and powerful inhibitory effect on MCF-7 MIII tumors, bombesin/gastrin-releasing peptide antagonist RC-3095 might be considered as a possible new agent for the treatment of breast cancer.

Topics: Animals; Antineoplastic Agents; Bombesin; Breast Neoplasms; Cell Division; Epidermal Growth Factor; Female; Gonadotropin-Releasing Hormone; Humans; Insulin-Like Growth Factor I; Luteinizing Hormone; Mice; Mice, Nude; Neoplasm Transplantation; Peptide Fragments; Tumor Cells, Cultured