Prevalence of PD-L1 in Cervical Cancer Patients and the Potential for Combining an Immune Checkpoint Inhibitor With Lenvatinib.

BACKGROUND/AIM: Cervical cancer is the fourth most common cause of cancer-related deaths in women worldwide. The potential for targeted therapy against the immune checkpoint programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) and receptor tyrosine kinases was examined in cervical cancer patients and cell lines. MATERIALS AND METHODS: On tissue microarrays, PD-L1 was analyzed in 123 samples of patients with cervical cancer using immunohistochemistry. In SiHa, HeLa, and CaSki cervical cancer cell lines we examined the combination of lenvatinib with a PD-1/PD-L1 inhibitor using cell viability assays, the activation of cell signaling pathway proteins using western blots and gene expression using quantitative reverse transcriptase-PCR. RESULTS: Of 113 evaluable samples, 90 (79.6%) had more than 1% PD-L1 positive cells. The single treatment with the PD-1/PD-L1 inhibitor resulted in the greatest reduction in growth for CaSki and lenvatinib in HeLa cells. In contrast, the combined treatment of lenvatinib with the PD-1/PD-L1 inhibitor demonstrated a significantly stronger impeded proliferation compared to the single treatment in all three cell lines. Moreover, the combined treatment caused significantly less phosphorylation of the signaling molecules ERK and S6 in SiHa and of S6 and STAT3 in HeLa cells but not in CaSki. All treatments diminished the mRNA levels of PD-L1, Il-8, and FGFR in SiHa cells. CONCLUSION: PD1 is frequently expressed in cervical cancer samples. Combining lenvatinib with a PD-1/PD-L1 inhibitor diminished proliferation of cervical cancer cell lines. Consequently, this combination might be a promising option to treat cervical cancer. Signaling pathways involved in tumor cell growth are blocked by the combined treatment but still a model of the underlying mechanism cannot be drawn.

Distribution of HPV Subtypes in Diverse Anogenital and Oral Samples from Women and Correlation of Infections with Neoplasia of the Cervix.

BACKGROUND: Cancers and intraepithelial lesions of different anogenital areas as well as oral cancer are associated with human papilloma virus (HPV) infections. METHODS: In this study cervical, vaginal, vulvar, anal, and oral samples were taken from 509 patients visiting our dysplasia consultation clinic. HPV genotyping was performed using the EUROArray HPV test. RESULTS: Positivity of HR HPV was found in 60.4-64.3% of anogenital and 14.6% of oral samples. HPV 16 showed the highest incidence in all investigated areas. In cervical and vaginal samples HPV 31 was detected second most, while in vulvar, anal, and oral samples HPV 53 was the second most common subtype. HPV 18 was found lower in all areas, while HPV 51, HPV 52, and HPV 73 were detected higher than expected from published data. A good concordance between cervical, vaginal and vulvar samples was examined for most of the HPV. HR HPV infection was higher in cervical cancer (CC; 91.7%) and high-grade intraepithelial squamous lesions (HSIL; 93.9%) compared to low-grade SIL (LSIL; 69.6%) and normal samples (44.8%). CONCLUSION: In addition to the well described HPV subtypes, we found others with high incidences in the investigated areas which may be evident for HSIL and CC of those areas.

Inhibitors of PD-1/PD-L1 and ERK1/2 impede the proliferation of receptor positive and triple-negative breast cancer cell lines.

PURPOSE: Triple-negative breast cancer (TNBC) is characterized by an unfavorable prognosis and missing systemic therapeutic approaches beside chemotherapy. Targeting the immune checkpoint PD-1/PD-L1 showed promising results in breast cancer and especially in TNBC. The extracellular signal-regulated kinase 1/2 (ERK1/2) is an important driver of carcinogenesis. Here, the effect of combined PD-1/PD-L1 and ERK1/2 inhibitor treatment is investigated of cell growth and intracellular impact of breast cancer cell lines. METHODS: The IC50 values of each inhibitor and the effect of combined treatment were determined in three TNBC cell lines of different subtypes and one non-TNBC cell line. Phospho-specific antibodies were used in western blot analyses to investigate an effect on ERK1/2 activation. Expressions of immune modulatory and cell cycle-associated genes were examined by quantitative reverse transcription PCR. RESULTS: Both inhibitors PD-1/PD-L1 and ERK1/2 impeded the proliferation of TNBC to a higher extent than of non-TNBC. By combined treatment, cell lines were inhibited either synergistically or additively. ERK1/2 and S6 phosphorylation were reduced and expressions of c-Fos and FosL were diminished after ERK1/2 inhibitor as single and combined treatment. Between genes involved in immune modulation, IL-8 was upregulated in TNBC cells after combined treatment. CONCLUSION: In conclusion, combination of PD-1/PD-L1 and ERK1/2 inhibitors showed favorable effects for a new therapy strategy, with better results in TNBC cell lines than in non-TNBC cells. The effects have to be validated in models that can reflect the interaction between immune and tumor cells like the situation in the tumor micro-environment.

PSMD9 expression correlates with recurrence after radiotherapy in patients with cervical cancer.

In the current retrospective cohort study, the expression of the Proteasome 26S non-ATPase Subunit 9 (PSMD9) was investigated in 102 patients with cervical cancer. The rat homologue of PSMD9, Bridge-1, was identified as a binding protein of the transcription factors PDX-1 and E-12 via its PDZ-domain. The aim of the current study was to evaluate the prognostic or predictive value of PSMD9 expression as a biomarker for patients with cervical cancer. Tissue microarrays were constructed from formalin-fixed paraffin-embedded tissue specimens of cervical cancer and peritumoral stroma after hysterectomy and a Bridge-1 antibody was used to perform immunohistochemistry. The immunoreactions were analyzed using an immunoreactive score, which evaluated the number of positive cells as well as their intensity of PSMD9 expression. A misinterpretation of statistically significant results after multiple testing was controlled by the false discovery rate correction using the algorithm of Benjamini and Hochberg. All tumor tissues and almost all peritumoral stroma tissues expressed PSMD9. The PSMD9 expression in tumor tissues was significantly higher compared with the peritumoral stroma. PSMD9 expression correlated significantly with the expression of the proliferation marker MIB-1. Patients with stronger PSMD9 expression tended to exhibit a higher odds ratio for the recurrence of the disease in all patients (n=102) as well as in the subgroup of 47 patients having received a combined chemoradiotherapy following hysterectomy. In the group of 62 patients having that received radiotherapy following hysterectomy, which included the chemoradiotherapy patients, a higher PSMD9 expression significantly increased the odds for a recurrence to 1.983-fold even after FDR correction (P=0.0304). In conclusion, PSMD9 was indicated to be overexpressed in tumor tissues and associated with tumor cell proliferation. Therefore, PSMD9 may be useful as a tumor marker. Furthermore, increased PSMD9 overexpression may be used to predict resistance against radiation.

Analysis of HPV genotype-specific concordance between EUROArray HPV and HPV 3.5 LCD-Array Kit in cervical samples of 163 patients.

PURPOSE: Human papilloma virus (HPV) as the most common viral infection of the anogenital tract is highly associated with intraepithelial neoplasia and cancer of the cervix and other anogential regions. To date, 15 high-risk (HR-) HPV and 3 probably/possibly HR-HPVs have been found to be associated with cervical cancer. Therefore, a screening especially for HR-HPV by appropriate tests is important for detection of precancerous lesions to prevent cancer. The purpose of this study was to analyze prospectively the concordance of the EUROArray HPV genotyping assay (Euroimmun; EUROArray) and the HPV 3.5 LCD-Array Kit (Chipron; LCD-Array). METHODS: Liquid-based, clinician-collected cervical cytology samples (n = 163) from women undergoing cervical inspection at the dysplasia consultation in the colposcopy clinic at the Medical Center-University of Freiburg, Germany were analyzed. Genotype-specific agreement was assessed by Cohen's kappa statistic and McNemar's P value of significance between proportions. RESULTS: Seventeen of the HR-HPV genotypes included in both assays were detected in 42.3% and 38% of samples by EUROArray and by LCD-Array, respectively; i.e. an agreement of 92.0% and a kappa value of 0.83 could be proven between the EUROArray and the LCD-Array. In 50 of 72 samples, identical HR-HPV genotypes were analyzed (81.9%, κ = 0.47) and genotyping for HPV 16 and/or 18 was highly concordant in both tests (relative agreement 96.3%, κ = 0.88). Detection of any HR-HPV was not significantly different after comparison of EUROArray with LCD-Array. CONCLUSION: Both of the tests showed comparable results for the detection of HPV in cervical specimens and permit these assays to be suitable for routine diagnostics.

Effects of Combined Treatment with Vitamin D and COX2 Inhibitors on Breast Cancer Cell Lines.

BACKGROUND: Vitamin D is known for its anticancer potential. Prostaglandin E2 (PGE2) is a proliferative and inflammation-activating agent. The production of PGE2 is dependent on the activity of cyclooxygenase-2 (COX2). A link between vitamin D and PGE2 metabolism was shown recently. MATERIALS AND METHODS: In MDA-MB-231 and MCF-7 breast cancer cell lines, we investigated the influence of calcitriol and the COX2 inhibitor celecoxib on cell growth via the MTT test, as well as on the protein and mRNA expression of COX2 using western blot and quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: The proliferation of MCF-7 and MDA-MB-231 was inhibited by both calcitriol and the COX2 inhibitor celecoxib and even more strongly by their combination. Moreover, calcitriol inhibited COX2 protein expression in MDA-MB-231 cells, as well as COX2 mRNA expression in both cell lines. CONCLUSION: The combination of calcitriol and celecoxib demonstrated a synergistic growth-inhibitory effect in breast cancer cell lines.

Claudin-1 expression in cervical cancer.

Claudin-1 is a tight junction protein that has been demonstrated to be involved in tumorigenesis and tumor progression in various types of solid tumors. In the present study, the protein expression of claudin-1 in squamous cervical cancer tissues obtained from 106 patients was analyzed by immunohistochemistry. In addition, the grade of claudin-1 expression was analyzed for associations with certain clinicopathological parameters. A significant overexpression of claudin-1 was detected in the tumor cells, when compared with that in the peritumoral stroma. There was no significant association between claudin-1 expression and FIGO stage, tumor size, grading or the appearance of distant metastases. Cervical cancer patients scoring positive for claudin-1 protein expression tended to exhibit more lymph node metastasis (28.3%), compared with claudin-1-negative patients (7.1%). Regarding overall survival, the results of the present study suggest a better prognosis for claudin-1-negative patients. In order to elucidate whether claudin-1 overexpression has a significant prognostic impact on squamous cervical cancer, further studies are required.

Effects of an Antagonistic Analog of Growth Hormone-Releasing Hormone on Endometriosis in a Mouse Model and In Vitro.

Endometriosis is a benign gynecologic disorder causing dysmenorrhea, pelvic pain, and subfertility. Receptors for the growth hormone-releasing hormone (GHRH) were found in endometriotic tissues. Antagonists of GHRH have been used to inhibit the growth of endometriotic endometrial stromal cells. In this study, the GHRH receptor splice variant (SV) 1 was detected in human endometrial tissue samples by Western blots and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The highest messenger RNA (mRNA) and protein levels of SV1 were found in eutopic endometrium from patients with endometriosis compared to ectopic endometriotic tissues and endometrium from normal patients. The highest expression for GHRH mRNA was found by qRT-PCR in ectopic endometriosis lesions. In an in vivo mouse model with human endometrial explants from patients with endometriosis, 10 µg MIA-602 per day resulted in significantly smaller human endometrial xenotransplants after 4 weeks compared to mice treated with vehicle. The endometrial tissues expressed SV1 before and after xenotransplantation. The proliferation of endometrial stromal cells as well as the endometriosis cell lines 12-Z and 49-Z was decreased by exposure to 1 µM MIA-602 after 72 hours. The protein levels of epithelial growth factor receptors in 12-Z and 49-Z cell lines were reduced 48 and 72 hours after the administration of 1 µM MIA-602. MIA-602 decreased the activation of the MAP-kinases ERK-1/2. Our study demonstrates the presence of SV1 receptor as a target for treatment with GHRH antagonist in endometriosis. Endometrial tissues respond to MIA-602 with inhibition of proliferation in vitro and in vivo. The use of MIA-602 could be an effective supplement to the treatment strategies in endometriosis.

Disrupting Y-Box-Binding Protein 1 Function Using OSU-03012 Prevents Endometriosis Progression in In Vitro and In Vivo Models.

The objective of the present study was to test the ability of OSU-03012 (2-amino-N-[4-[5-phenanthren-2-yl-3-(trifluoromethyl)pyrazol-1-yl]phenyl]acetamide), a novel and potent celecoxib-derivative, to impair endometriosis progression in in vitro and in vivo models based on its ability to indirectly block Y-box-binding protein 1 (YB-1) function. 12Z human endometriotic epithelial cells and sexually mature female C57BL/6J mice were treated with OSU-03012. Cellular proliferation was quantified by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromid assay. Expression of YB-1 and phosphorylated YB-1 in 12Z cells and endometriotic lesions was evaluated by Western blotting and immunohistochemistry (IHC). The IHC for proliferating cell nuclear antigen was performed. OSU-03012 treatment resulted in decreased YB-1 and its phosphorylated form in both in vitro and in vivo models. Endometriotic lesion size was significantly reduced in OSU-03012-treated mice (27.6 ± 4.0 mm3) compared to those from the control group (50.5 ± 6.9 mm3, P < .0001). A significant reduction in endometriotic epithelial cell proliferation was observed in endometriotic lesions exposed to OSU-03012 treatment ( P = .0346). In conclusion, targeting YB-1 via OSU-03012 showed a potent antiproliferative effect on endometriotic epithelial cells in vitro and in a mouse model of disease.

Expression of cyclooxygenase-2 in cervical cancer is associated with lymphovascular invasion.

Cyclooxygenase-2 (COX-2) is associated with carcinogenesis and tumor progression. The current study analyzed the effect of COX-2 expression in patients with invasive squamous cervical cancer. Tissue samples from 123 cervical cancer patients were collected for a retrospective analysis using immunohistochemistry (IHC) with an antibody against COX-2. The clinical and survival data of the patients were analyzed. Positive staining for COX-2 (defined as an immunoreactivity score of ≥4) was detected in 28 patients (23%), with significantly higher percentages of staining in tumor cells compared with peritumoral stroma cells (P<0.001). COX-2 expression was significantly associated with lymphovascular space invasion (LVSI; P=0.017). The association of COX-2 expression with LVSI suggests a possible effect of COX-2 on tumor progression in cervical cancer. Further studies including larger patient collectives are required in order to perform analyses of clinical subgroups and patient survival.

Subtypes of Triple-negative Breast Cancer Cell Lines React Differently to Eribulin Mesylate.

BACKGROUND/AIM: Diagnosis of triple-negative breast cancer (TNBC) is associated with adverse prognosis, particularly in cases of chemotherapy resistance. The goal of this analysis was to compare TNBC vs. non-TNBC cell lines and those of distinct TNBC subtypes with regard to sensitivity to eribulin in vitro. MATERIALS AND METHODS: Breast cancer cell lines were subjected to cell-viability assays, apoptosis analyses, migration and invasion experiments, and quantitative real-time polymerase chain reaction after exposure to eribulin. RESULTS: Eribulin reduced cell viability in TNBC and non-TNBC cell lines in the sub-nanomolar range. Furthermore, exposure to eribulin induced apoptosis and decreased the rate of migration and invasion. Genes known to induce malignant transformation were differentially expressed after eribulin treatment. CONCLUSION: Eribulin had a strong antiproliferative effect on breast cancer cell lines, although we did not observe a significant difference between TNBC and non-TNBC cell lines with regard to sensitivity to eribulin.

Combined treatment of breast cancer cell lines with vitamin D and COX-2 inhibitors.

BACKGROUND: Vitamin D is known for its anti-cancerogenous potential. Prostaglandin E2 (PGE2) is a proliferation and inflammation activating agent. The production of PGE2 is dependent on the activity of cyclooxygenase-2 (COX-2). A link between vitamin D and PGE2 metabolism was recently shown. MATERIALS AND METHODS: In MDA-MB-231 and MCF-7 breast cancer cell lines we investigated the influence of calcitriol and the COX-2 inhibitor celecoxib regarding cell growth via MTT test, as well as on the protein and mRNA expression of COX-2 using western blot and qRT-PCR. RESULTS: The proliferation of MCF-7 and MDA-MB-231 was inhibited by both calcitriol and the COX-2 inhibitor celecoxib and even stronger by their combination. Moreover, calcitriol inhibited the COX-2 protein expression in MDA-MB-231, as well as the COX-2 mRNA expression in both cell lines. CONCLUSION: The combination of calcitriol and celecoxib demonstrated a cooperative growth-inhibiting effect in breast cancer cell lines.

Vitamin D inhibits ovarian cancer cell line proliferation in combination with celecoxib and suppresses cyclooxygenase-2 expression.

BACKGROUND: Vitamin D exhibits multiple anti-proliferative and pro-differentiating actions. Prostaglandin-(PG)E2 is a tumor-promoting tissue hormone anabolized by cyclooxygenase-2 (COX-2). Recently, a link between the PG and vitamin D metabolism was reported. MATERIALS AND METHODS: The influence of calcitriol and celecoxib on the proliferation of ovarian cancer cell lines was measured and the impact of calcitriol on the protein and mRNA expression of COX-2 was quantified by western blot and qRT-PCR, respectively. RESULTS: After COX-2 induction with interleukin (IL)-1ß, 10 µM celecoxib did not significantly inhibit the proliferation of OVCAR-3 cells, whereas calcitriol showed such an effect; however, the combination of the two substances had an additive influence. After induction by IL-1ß, calcitriol inhibited the COX-2 protein, as well as its mRNA expression significantly in OVCAR-3 and SKOV-3 cells. CONCLUSION: These data suggest a correlation between PG and vitamin D metabolism in their anti-tumorigenic activity in ovarian carcinomas.

Slow-freezing versus vitrification for human ovarian tissue cryopreservation.

PURPOSE: Ovarian tissue can be cryopreserved prior to chemotherapy using either the slow-freezing or the vitrification method; however, the data on the equality of the procedures are still conflicting. In this study, a comparison of the cryo-damage of human ovarian tissue induced by either vitrification or slow-freezing was performed. METHODS: Ovarian tissue from 23 pre-menopausal patients was cryopreserved with either slow-freezing or vitrification. After thawing/warming, the tissue was histologically and immunohistochemically analyzed and cultured in vitro. During tissue culture the estradiol release was assessed. RESULTS: No significant difference was found in the proportion of high-quality follicles after thawing/warming in the slow-freezing and vitrification group, respectively (72.7 versus 66.7 %, p = 0.733). Estradiol secretion by the ovarian tissue was similar between groups during 18 days in vitro culture (area-under-the-curve 5,411 versus 13,102, p = 0.11). Addition of Sphingosine-1-Phosphate or Activin A to the culture medium did not alter estradiol release in both groups. The proportion of Activated Caspase-3 or 'Proliferating-Cell-Nuclear-Antigen' positive follicles at the end of the culture period was similar between slow-freezing and vitrification. CONCLUSION(S): Slow-freezing and vitrification result in similar morphological integrity after cryopreservation, a similar estradiol release in culture, and similar rates of follicular proliferation and apoptosis after culture.

Growth-modulatory effects of heparin and VEGF165 on the choriocarcinoma cell-line JEG-3 and its expression of heparanase.

BACKGROUND: Expression of heparanase (HPSE) in tumor cells is strongly associated with invasion, metastasis and angiogenesis. It also plays a key role during pregnancy, in processes of implantation as well as placentation. Vascular endothelial growth factor (VEGF) and heparin are known to alter HPSE expression, with heparin given prophylactically to women with a history of placenta-mediated complications in subsequent pregnancies. MATERIALS AND METHODS: We examined the growth-modulatory effects of different concentrations of heparin and VEGF on the choriocarcinoma cell-line JEG-3 and the expression of heparanase under VEGF and heparin by proliferation assays, PCR, and western blot. RESULTS: Proliferation of JEG-3 cells was induced by heparin in a dose-dependent manner, whereas highly concentrated VEGF led to a decreased cell proliferation. Both agents did not influence the HPSE-expression. CONCLUSION: The presumed pregnancy-protecting effects of heparin may partially be due to an increase of trophoblast proliferation and not via regulation of HPSE expression.

L1 cell adhesion molecule as a potential therapeutic target in murine models of endometriosis using a monoclonal antibody approach.

BACKGROUND/AIMS: The neural cell adhesion molecule L1CAM is a transmembrane glycoprotein abnormally expressed in tumors and previously associated with cell proliferation, adhesion and invasion, as well as neurite outgrowth in endometriosis. Being an attractive target molecule for antibody-based therapy, the present study assessed the ability of the monoclonal anti-L1 antibody (anti-L1 mAb) to impair the development of endometriotic lesions in vivo and endometriosis-associated nerve fiber growth. METHODS AND RESULTS: Endometriosis was experimentally induced in sexually mature B6C3F1 (n=34) and CD-1 nude (n=21) mice by autologous and heterologous transplantation, respectively, of endometrial fragments into the peritoneal cavity. Transplantation was confirmed four weeks post-surgery by in vivo magnetic resonance imaging and laparotomy, respectively. Mice were then intraperitoneally injected with anti-L1 mAb or an IgG isotype control antibody twice weekly, over a period of four weeks. Upon treatment completion, mice were sacrificed and endometrial implants were excised, measured and fixed. Endometriosis was histologically confirmed and L1CAM was detected by immunohistochemistry. Endometriotic lesion size was significantly reduced in anti-L1-treated B6C3F1 and CD-1 nude mice compared to mice treated with control antibody (P<0.05). Accordingly, a decreased number of PCNA positive epithelial and stromal cells was detected in autologously and heterologously induced endometriotic lesions exposed to anti-L1 mAb treatment. Anti-L1-treated mice also presented a diminished number of intraperitoneal adhesions at implantation sites compared with controls. Furthermore, a double-blind counting of anti-neurofilament L stained nerves revealed significantly reduced nerve density within peritoneal lesions in anti-L1 treated B6C3F1 mice (P=0.0039). CONCLUSIONS: Local anti-L1 mAb treatment suppressed endometriosis growth in B6C3F1 and CD-1 nude mice and exerted a potent anti-neurogenic effect on induced endometriotic lesions in vivo. The findings of this preliminary study in mice provide a strong basis for further testing in in vivo models.

Targeting triple-negative breast cancer through the somatostatin receptor with the new cytotoxic somatostatin analogue AN-162 [AEZS-124].

Previously, we have shown that the targeted cytotoxic somatostatin (sst) analogue AN-162 [AZSE-124] inhibits the growth of MDA-MB-231 human breast cancers xenografted into nude mice. In this study, we examined the trafficking of AN-162 into the cell, the expression of the somatostatin receptors (sstr) in specimens of human triple-negative breast cancers (TNBC), and the effect of AN-162 on HCC 1806 human TNBC xenografts. The expression of sstr in TNBC tumor samples was investigated by immunohistochemical staining. The expression of sstr in HCC 1806 was evaluated by reverse transcription PCR. Internalization studies with I-labeled AN-162 were carried out and the autofluorescence sign of doxorubicin moiety in the cell nucleus after incubation with AN-162 was measured using a fluorescence assay. The effects of AN-162 on the growth of HCC 1806 xenografted into nude mice were studied. A fluorescence microscopy cytotoxicity assay in vitro to detect cell death after treatment with AN-162 was also carried out. About 28% of TNBC tumor specimens showed a positive staining for sstr subtype 2a. HCC 1806 expresses all five subtypes of sstr. In the fluorescence cytotoxicity assay, dead HCC 1806 cells were found 24 h after incubation with AN-162. The growth of HCC 1806 tumors in nude mice was significantly inhibited by treatment with AN-162. AN-162 was internalized into the HCC 1806 cells and doxorubicin moiety was detected in the cell nuclei. This study is the first to show that the trafficking of the cytotoxic sst analogue AN-162 into the cell is mediated by sstr. Our work shows that the growth of xenografted HCC 1806 TNBCs can be effectively inhibited in vivo with AN-162. This investigation provides information on the mechanism of action and efficacy of this new targeted cytotoxic sst analogue and identifies in this relation the sstr as a favorable therapeutic target in TNBC.

The effects of cetrorelix and triptorelin on the viability and steroidogenesis of cultured human granulosa luteinized cells.

BACKGROUND: We investigated the effects of the gonadotropin-releasing hormone (GnRH) agonist triptorelin as well the GnRH antagonist cetrorelix those of on the viability and steroidogenesis in human granulosa luteinized (hGL) cell cultures. MATERIALS AND METHODS: The hGL cells were obtained from 34 women undergoing ovarian stimulation for IVF treatment. The cells were cultured for 48 h with or without 1 nM or 3 nM of cetrorelix or triptorelin in serum-free media. The cell viability was evaluated by the MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay. The concentrations of estradiol and progesterone in culture supernatants were measured by ELISA. RESULTS: Treatment with triptorelin slightly increased cell viability, whereas treatment with 3 nM cetrorelix led to a significant decrease. Estradiol concentrations were reduced with 3 nM triptorelin. Cultures treated with high-dose of either cetrorelix or triptorelin tended to secrete less progesterone than controls. CONCLUSION: Cetrorelix significantly reduces the viability of hGL cells. Triptorelin and cetrorelix may have minor effects on steroidogenesis. These results suggest that GnRH analogues may influence ovarian functions.

Influence of calcitriol on prostaglandin- and vitamin D-metabolising enzymes in benign and malignant breast cell lines.

BACKGROUND: Cyclooxygenase-2 (COX-2) is a potential molecular prognostic factor for breast cancer, and calcitriol [1,25(OH)(2)D(3)], the biologically active form of vitamin D, is a promising target in breast cancer therapy. MATERIALS AND METHODS: The influence of calcitriol on the proliferation and the effects of calcitriol on the expression of prostaglandin- and vitamin D-metabolising enzymes were examined in benign and malignant breast cells. RESULTS: Calcitriol inhibited the proliferation of MCF-10F and MCF-7 cells but not of invasive MDA-MB-231 cells and reduced the expression of COX-2 and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in the benign breast cell line MCF-10F. Furthermore, dysregulation in vitamin D-metabolising proteins was detected, especially in MDA-MB-231 cells. CONCLUSION: These results suggest dysregulation of vitamin D metabolism and a lack of a possible influence of calcitriol on the metabolism of prostaglandins in the malignant breast cell lines.

Expression of prostaglandin- and vitamin D-metabolising enzymes in benign and malignant breast cells.

BACKGROUND: Cyclooxygenase-2 (COX-2) plays a crucial role in prognosis of malignancy and has been associated with carcinogenesis, particularly neoangiogenesis and tumor progression. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is described as a tumour suppressor in cancer. The antiproliferative effects of calcitriol [1,25(OH)(2)D(3)] mediated via the vitamin D receptor (VDR) render vitamin D a promising target in breast cancer therapy. MATERIALS AND METHODS: The expression of prostaglandin (PG)-metabolizing enzymes, vitamin D-metabolising enzymes and VDR were determined in benign and malignant breast cell lines using western blot analysis. RESULTS: We detected an inverse correlation between the two types of metabolism, a reduced VDR expression in the malignant breast cell lines, and therefore an insufficient induction of 24-hydroxylase in the malignant cells. CONCLUSION: We suggest the possibility of dysregulation of vitamin D-metabolizing enzymes in malignant breast cell lines.