scholarly journals Estrogen Receptor Alpha (ER-α) and Beta (ER-β) mRNAs in Normal Ovary, Ovarian Serous Cystadenocarcinoma and Ovarian Cancer Cell Lines: Down-Regulation of ER-β in Neoplastic Tissues

1998 ◽  
Vol 83 (3) ◽  
pp. 1025-1028 ◽  
Author(s):  
Alfred W. Brandenberger ◽  
Meng Kian Tee ◽  
Roberts B. Jaffe
Keyword(s):  
Ovarian Cancer ◽  
Estrogen Receptor ◽  
Granulosa Cells ◽  
Ovarian Cancer Cell ◽  
Ovarian Surface Epithelium ◽  
Surface Epithelium ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Low Level ◽  
Ovarian Cancer Cell Lines

The prognosis in ovarian carcinoma, the most lethal of the gynecologic neoplasms, is poor and has changed little in the last three decades. Only a small number respond to antiestrogen therapy, although the classic estrogen receptor, ER-α, has been identified in ovarian surface epithelium, from which approximately 90% of ovarian cancers originate. We have previously shown that ER-β mRNA is most abundant in human fetal ovaries, suggesting that it might play an important role in ovarian development. Therefore, we investigated the mRNA levels of both ERs in normal ovaries, ovarian serous cystadenocarcinomas, granulosa cells from patients undergoing in vitro fertilization (IVF), the ovarian surface epithelium cell line IOSE-Van, and the ovarian cancer cell lines SKOV3, HEY and OCC1. Northern blots of normal and neoplastic ovaries were hybridized with an ER-β riboprobe that spans the A/B domain. We detected two major hybridizing bands at approximately 8 and 10 kb. An RNase protection assay using the same probe revealed a single band of the expected size. Hybridizing the same blot with an ER-α riboprobe showed a strong hybridizing band at approximately 6.5 kb. In ovarian cancer samples, ER-β mRNA level was decreased when compared to normal ovaries. Using 25 cycles of RT-PCR followed by Southern blotting, we found equal amounts of ER-α and -β mRNAs in normal ovaries in all age groups from 33 to 75 years; however, in ovarian cancer tissue, the level of ER-α mRNA was similar or slightly higher, comparable to 103 to 104 copies of plasmid DNA, but ER-β mRNA levels were markedly decreased. Granulosa cells from IVF patients expressed high levels of ER-β mRNA. The OSE cell line expressed low level of ER-α, detectable after 40 cycles of RT-PCR and no ER-β mRNA. SKOV3, showed low level of ER-α and β mRNAs, whereas OCC1 showed low level of ER-β and relatively high level of ER-α. HEY did not contain detectable amounts of either ER after 40 cycles of RT-PCR. We found no evidence of differential splicing or major deletions in almost the entire coding region of ER-β in either normal ovaries or tumor samples.

scholarly journals Differential regulation of two forms of gonadotropin-releasing hormone messenger ribonucleic acid by gonadotropins in human immortalized ovarian surface epithelium and ovarian cancer cells

2006 ◽  
Vol 13 (2) ◽  
pp. 641-651 ◽  
Author(s):  
Jung-Hye Choi ◽  
Kyung-Chul Choi ◽  
Nelly Auersperg ◽  
Peter C K Leung
Keyword(s):  
Ovarian Cancer ◽  
Cell Lines ◽  
Ovarian Cancer Cell ◽  
Ovarian Surface Epithelium ◽  
Gonadotropin Releasing Hormone ◽  
Surface Epithelium ◽  
Ovarian Cancer Cells ◽  
Mrna Levels ◽  
Ovarian Surface ◽  
Ovarian Cancer Cell Lines

Although gonadotropin-releasing hormone (GnRH) has been shown to play a role as an autocrine/ paracrine regulator of cell growth in ovarian surface epithelium and ovarian cancer, the factors which regulate the expression of GnRH and its receptor in these cells are not well characterized. In the present study, we employed real-time PCR to determine the potential regulatory effect of gonadotropins on the expression levels of GnRH I (the mammalian GnRH), GnRH II (a second form of GnRH) and their common receptor (GnRHR) in immortalized ovarian surface epithelial (IOSE-80 and IOSE-80PC) cells and ovarian cancer cell lines (A2780, BG-1, CaOV-3, OVCAR-3 and SKOV-3). The cells were treated with increasing concentrations (100 and 1000 ng/ml) of recombinant follicle-stimulating hormone (FSH) or luteinizing hormone (LH) for 24 h. Treatment with FSH or LH reduced GnRH II mRNA levels in both IOSE cell lines and in three out of five ovarian cancer cell lines (A2780, BG-1 and OVCAR-3). A significant decrease in GnRHR mRNA levels was observed in IOSE and ovarian cancer cells, except CaOV-3 cells, following treatment with FSH or LH. In contrast, treatment with either FSH or LH had no effect on GnRH I mRNA levels in these cells, suggesting that gonadotropins regulate the two forms of GnRH and its receptor differentially. In separate experiments, the effect of gonadotropins on the anti-proliferative action of GnRH I and GnRH II agonists in IOSE-80, OVCAR-3 and SKOV-3 cells was investigated. The cells were pretreated with FSH or LH (100 ng/ml) for 24 h after which they were treated with either GnRH I or GnRH II (100 ng/ml) for 2 days, and cell growth was assessed by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] assay. Pretreatment of the cells with FSH or LH significantly reversed the growth inhibitory effect of GnRH I and GnRH II agonists in these cell types. These results provide the first demonstration of a potential interaction between gonadotropins and the GnRH system in the growth regulation of normal ovarian surface epithelium and its neoplastic counterparts.

scholarly journals Role of Gonadotropin-Releasing Hormone as an Autocrine Growth Factor in Human Ovarian Surface Epithelium1

Endocrinology ◽  
2000 ◽  
Vol 141 (1) ◽  
pp. 72-80 ◽  
Author(s):  
Sung Keun Kang ◽  
Kyung-Chul Choi ◽  
Kwai Wa Cheng ◽  
Parimal S. Nathwani ◽  
Nelly Auersperg ◽  
...  
Keyword(s):  
Gnrh Agonist ◽  
Messenger Rna ◽  
Ovarian Surface Epithelium ◽  
Inhibitory Effect ◽  
Surface Epithelium ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Ovarian Surface ◽  
Ovarian Surface Epithelial

Abstract Epithelial ovarian cancer, which accounts for 80–90% of all ovarian cancers, is the most common cause of death from gynecological malignancies and is believed to originate from the ovarian surface epithelium. In the present study we investigated the expression of GnRH and its receptor in human ovarian surface epithelial (hOSE) cells and provided novel evidence that GnRH may have antiproliferative effects in this tissue. Using RT-PCR and Southern blot analysis, we cloned the GnRH and GnRH receptor (GnRHR) in hOSE cells. Sequence analysis revealed that GnRH and its receptor have sequences identical to those found in the hypothalamus and pituitary, respectively. To address whether GnRH regulates its own and receptor messenger RNA (mRNA), the cells were treated with different concentrations of the GnRH agonist (d-Ala6)-GnRH. Expression levels of GnRH and its receptor were investigated using quantitative and competitive RT-PCR, respectively. Interestingly, a biphasic effect was observed for the GnRH and GnRHR mRNA levels. High concentrations of the GnRH agonist (10−7 and 10−9m) decreased GnRH and GnRHR mRNA levels, whereas a low concentration (10−11m) resulted in up-regulation of GnRH and receptor mRNA levels. Treatment with the GnRH antagonist, antide, prevented the biphasic effects of the GnRH agonist in hOSE cells, confirming the specificity of the response. Furthermore, to investigate the physiological significance, we studied receptor-mediated growth regulatory effects of GnRH in human ovarian surface epithelial cells. The cells were treated with GnRH analogs, and the proliferative index of cells was measured using a [3H]thymidine incorporation assay. (d-Ala6)-GnRH had a direct inhibitory effect on the growth of hOSE cells in a time- and dose-dependent manner. This antiproliferative effect of the GnRH agonist was receptor mediated, as cotreatment of hOSE cells with antide abolished the growth inhibitory effects of the GnRH agonist. The results strongly suggest that GnRH can act as an autocrine/paracrine regulator in hOSE cells.

scholarly journals Pigment Epithelium-Derived Factor Is Estrogen Sensitive and Inhibits the Growth of Human Ovarian Cancer and Ovarian Surface Epithelial Cells

Endocrinology ◽  
2006 ◽  
Vol 147 (9) ◽  
pp. 4179-4191 ◽  
Author(s):  
Lydia W. T. Cheung ◽  
Simon C. L. Au ◽  
Annie N. Y. Cheung ◽  
Hextan Y. S. Ngan ◽  
Joyce Tombran-Tink ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Estrogen Receptor ◽  
Cell Lines ◽  
Cancer Cell ◽  
Ovarian Cancer Cell ◽  
Pigment Epithelium ◽  
Cancer Cell Lines ◽  
Ovarian Surface ◽  
Pigment Epithelium Derived Factor ◽  
Ovarian Cancer Cell Lines

Epithelial ovarian carcinoma is the most lethal gynecological cancer. However, little is known about the molecular mechanisms underlying the disease development and progression. In this study, we found that the expression of pigment epithelium-derived factor (PEDF) was greatly reduced in ovarian tumors and in ovarian cancer cell lines when compared with their normal precursor, ovarian surface epithelium (OSE). In addition, we showed that exogenous PEDF inhibited the growth of cultured human OSE as well as ovarian cancer cell lines, whereas targeted inhibition of endogenous PEDF using small interfering RNA or neutralizing PEDF antibody promoted the growth of these cells, confirming that the growth-inhibitory effect was PEDF specific. We also report for the first time that estrogen is an important upstream regulator of PEDF in human OSE. Treatment of the cultured cells with 17β-estradiol (E2) inhibited the expression of PEDF protein and mRNA in a dose- and time-dependent manner, which could be reversed by the specific estrogen receptor antagonist, ICI 182,780, indicating that the regulation was estrogen receptor-mediated. We further showed that this down-regulation of PEDF gene transcription was a direct, primary effect of E2. E2 promoted OSE and ovarian cancer cell growth, whereas simultaneous treatment with E2 and PEDF abrogated the estrogenic growth stimulation of these cells. This study is the first to demonstrate a role of PEDF in OSE biology and ovarian cancer and suggests that the loss of PEDF may e of relevance in carcinogenesis.

Estrogen Receptor-β mRNA Expression in Rat Ovary: Down-Regulation by Gonadotropins

1997 ◽  
Vol 11 (2) ◽  
pp. 172-182 ◽  
Author(s):  
Michael Byers ◽  
George G. J. M. Kuiper ◽  
Jan-Åke Gustafsson ◽  
Ok-Kyong Park-Sarge
Keyword(s):  
Estrogen Receptor ◽  
In Situ Hybridization ◽  
Mrna Expression ◽  
Granulosa Cells ◽  
Mrna Levels ◽  
Rt Pcr ◽  
Adult Rats ◽  
Mature Adult ◽  
Preovulatory Follicles

Abstract We have examined the expression and regulation of the two estrogen receptor (ERα and ERβ) genes in the rat ovary, using Northern blotting, RT-PCR, and in situ hybridization histochemistry. Northern blotting results show that the ovary expresses both ERα and ERβ genes as single (∼6.5-kb) and multiple (ranging from ∼1.0-kb to ∼10.0-kb) transcripts, respectively. ERα mRNA is expressed at a level lower than ERβ mRNA in immature rat ovaries. This relationship appears unchanged between sexually mature adult rats and immature rats. In sexually mature adult rats undergoing endogenous hormonal changes, whole ovarian content of ERβ mRNA, as determined by RT-PCR, remained more or less constant with the exception of the evening of proestrus when ERβ mRNA levels were decreased. Examination of ERβ mRNA expression at the cellular level, by in situ hybridization, showed that ERβ mRNA is expressed preferentially in granulosa cells of small, growing, and preovulatory follicles, although weak expression of ERβ mRNA was observed in a subset of corpora lutea, and that the decrease in ERβ mRNA during proestrous evening is attributable, at least in part, to down-regulation of ERβ mRNA in the preovulatory follicles. This type of expression and regulation was not typical for ERα mRNA in the ovary. Although whole ovarian content of ERα mRNA was clearly detected by RT-PCR, no apparent modulation of ERα mRNA levels was observed during the estrous cycle. Examination of ERα mRNA expression at the cellular level, by in situ hybridization, showed that ERα mRNA is expressed at a low level throughout the ovary with no particular cellular localization. To further examine the potential role of the preovulatory pituitary gonadotropins in regulating ERβ mRNA expression in the ovary, we used immature rats treated with gonadotropins. In rats undergoing exogenous hormonal challenges, whole ovarian content of ERβ mRNA, as determined by RT-PCR, remained more or less unchanged after an injection of PMSG. In contrast, a subsequent injection of human CG (hCG) resulted in a substantial decrease in whole ovarian content of ERβ mRNA. In situ hybridization for ERβ mRNA shows that small, growing, and preovulatory follicles express ERβ mRNA in the granulosa cells. The preovulatory follicles contain ERβ mRNA at a level lower than that observed for small and growing follicles. In addition, there is an abrupt decrease in ERβ mRNA expression in the preovulatory follicles after hCG injection. The inhibitory effect of hCG on ERβ mRNA expression was also observed in cultured granulosa cells. Moreover, agents stimulating LH/CG receptor-associated intracellular signaling pathways (forskolin and a phorbol ester) readily mimicked the effect of hCG in down-regulating ERβ mRNA in cultured granulosa cells. Taken together, our results demonstrate that 1) the ovary expresses both ERα and ERβ genes, although ERβ is the predominant form of estrogen receptor in the ovary, 2) ERβ mRNA is localized predominantly to the granulosa cells of small, growing, and preovulatory follicles, and 3) the preovulatory LH surge down-regulates ERβ mRNA. These results clearly implicate the physiological importance of ERβ in female reproductive functions.

scholarly journals Cloning and Characterization of a Rat Ortholog of MMP-23 (Matrix Metalloproteinase-23), a Unique Type of Membrane-Anchored Matrix Metalloproteinase and Conditioned Switching of Its Expression during the Ovarian Follicular Development

2001 ◽  
Vol 15 (5) ◽  
pp. 747-764 ◽  
Author(s):  
Junji Ohnishi ◽  
Eriko Ohnishi ◽  
Mulan Jin ◽  
Wakako Hirano ◽  
Dai Nakane ◽  
...  
Keyword(s):  
Matrix Metalloproteinase ◽  
Granulosa Cells ◽  
Follicular Development ◽  
Ovarian Surface Epithelium ◽  
Interstitial Cells ◽  
Soluble Form ◽  
Surface Epithelium ◽  
Mrna Levels ◽  
Unique Type ◽  
Theca Externa

Abstract In our attempt to study the role of matrix metalloproteinases (MMPs) in the process of mammalian ovulation, we isolated a rat ortholog of the recently reported human MMP-23 from gonadotropin-primed immature rat ovaries. Transient expression of epitope-tagged rat and human MMP-23 in COS-1 cells revealed that they were synthesized as a membrane-anchored glycoprotein with type II topology. Indirect immunofluorescent analysis showed that subcellular localization of MMP-23 was predominantly in the perinuclear regions. The transfected human MMP-23 protein was processed endogenously to the soluble form in COS-1 cells. However, cotransfection of MMP-23 with the mouse furin cDNA did not enhance this processing, indicating that furin may not be involved in this event. Notably, in situ hybridization analysis revealed a dramatic switching of MMP-23 mRNA localization from granulosa cells to theca-externa/fibroblasts and ovarian surface epithelium during the follicular development. In serum-free primary culture of rat granulosa cells, a drastic diminution of MMP-23 mRNA expression was observed in response to FSH action between 24 h and 48 h of culture. The observed effect of FSH on MMP-23 expression was mimicked by treatment of granulosa cells with forskolin or 8-bromo (Br)-cAMP. In contrast, MMP-23 mRNA levels increased in theca-interstitial cells regardless of the presence of LH in the culture. However, treatment of theca-interstitial cells with forskolin or 8-Br-cAMP markedly reduced the expression of MMP-23 with a concomitant increase in progesterone production. These results indicate that the MMP-23 gene is spatially and temporally regulated in a cell type-specific manner in ovary via the cAMP signaling pathway.

Down-regulation of MDR1 by epigenetic alteration in human epithelial ovarian cancer cells

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e16556-e16556
Author(s):  
Y. Kawakami ◽  
K. Miyamoto ◽  
K. Takehara ◽  
M. Kumagai ◽  
O. Samura ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Dna Methylation ◽  
Ovarian Cancer Cell ◽  
Methylation Status ◽  
Mdr1 Gene ◽  
Human Ovarian Cancer ◽  
Rt Pcr ◽  
Specific Pcr ◽  
Ovarian Cancers ◽  
Ovarian Cancer Cell Lines

e16556 Background: Ovarian cancer is one of the most lethal malignancies in women. Despite recent studies of many oncogenes and tumor-suppressor genes concerning about its progression, the details of ovarian cancer biology still remains to be unclear. P-glycoprotein (P-gp) encoded by the MDR1 gene is a membrane protein that can export many kinds of antineoplastic agents from cells, and overexpression of P-gp has been reported to be implicated in treatment failure in cancer. DNA methylation, a major epigenetic process, can affect every step in carcinogenesis as well as genetic alterations. The contribution of such epigenetic alteration to the expression of MDR1 remains largely unexplored in human ovarian cancer. Methods: In this study, we evaluated the DNA methylation status of the MDR1 gene by methylation-specific PCR. Then, the expression of MDR-1 mRNA and protein in primary epithelial ovarian cancer specimens were evaluated by real-time RT-PCR and immunohistochemistry using anti-mouse P-gp F4 monoclonal antibody, respectively. The correlation between these results and clinicopathological features was examined. Results: MDR1 was hypermethylated in 12 of 12 (100%) ovarian cancer cell lines, and 5 of 13 (38%) primary ovarian cancers by methylation-specific PCR analysis. MDR1 mRNA expression was subsequently found to be lost in ovarian cancer cell lines with methylation by both real-time RT-PCR and immunohistochemistry. Thus, MDR1expression was associated with the DNA methylation status of the MDR1 gene. Conclusions: In conclusion, MDR1 was frequently hypermethylated in human ovarian cancers. Our results suggest that epigenetic regulation might play a role in the expression of MDR1 and clinical treatment outcomes in human ovarian cancer. No significant financial relationships to disclose.

scholarly journals Telomerase in the ovary

Reproduction ◽  
2010 ◽  
Vol 140 (2) ◽  
pp. 215-222 ◽  
Author(s):  
Jun-Ping Liu ◽  
He Li
Keyword(s):  
Ovarian Cancer ◽  
Germ Cells ◽  
Granulosa Cells ◽  
Reproductive Function ◽  
Ovarian Surface Epithelium ◽  
Malignant Cell ◽  
Telomerase Activity ◽  
Ovary Development ◽  
Surface Epithelium ◽  
Neoplastic Cells

Telomerase, an enzyme complex that binds the chromosome ends (telomeres) and maintains telomere length and integrity, is present in germ cells, proliferative granulosa cells, germline stem cells, and neoplastic cells in the ovary, but it is absent in differentiated or aged cells. Activation of telomerase in the ovary underpins both benign and malignant cell proliferation in several compartments, including the germ cells, membrana granulosa, and the ovarian surface epithelium. The difference in telomerase operation between normal and abnormal cell proliferations may lie in the mechanisms of telomerase activation in a deregulated manner. Recent studies have implicated telomerase activity in ovarian cancer as well as oogenesis and fertility. Inhibition of telomerase and the shortening of telomeres are seen in occult ovarian insufficiency. Studies of how telomerase operates and regulates ovary development may provide insight into the development of both germ cells for ovarian reproductive function and neoplastic cells in ovarian cancer. The current review summarizes the roles of telomerase in the development of oocytes and proliferation of granulosa cells during folliculogenesis and in the process of tumorigenesis. It also describes the regulation of telomerase by estrogen in the ovary.

scholarly journals Bexarotene-induced Cell Death in Ovarian Cancer Cells Through Caspase-4–mediated pyroptosis

2021 ◽  
Author(s):  
Tatsuya Kobayashi ◽  
Akira Mitsuhashi ◽  
Piao Hongying ◽  
Masashi Shioya ◽  
Kyoko Nishikimi ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Ovarian Cancer ◽  
Cell Death ◽  
Cell Lines ◽  
Cancer Cell ◽  
Ovarian Cancer Cell ◽  
Cancer Cell Lines ◽  
Ovarian Cancer Cells ◽  
Mrna Levels ◽  
Ovarian Cancer Cell Lines

Abstract Purpose: Bexarotene is selectively activates retinoid X recepto, whichr is a commonly used anticancer agent for cutaneous T-cell lymphoma. In this study, we aimed to investigate the anticancer effect of bexarotene and its underlying mechanism in ovarian cancer in vitro.Methods: The ES2 and NIH:OVACAR3 ovarian cancer cell lines were treated with 0, 5, 10, or 20 µM bexarotene. After 24 hours, cell number measurement and lactate dehydrogenase (LDH) cytotoxicity assay were performed. The effect of bexarotene on CDKN1A expression, pyroptosis, and apoptosis were evaluated.Results: Bexarotene reduced cell proliferation in all concentrations in both cells. At concentrations above 10 µM, it increased extracellular LDH activity with cell rupture. In both cells, 10 µM bexarotene treatment increased the CDKN1A mRNA levels and reduced cell cycle related protein expression. In ES2 cells, caspase-4 and GSDME were activated, whereas caspase-3 was not, indicating that bexarotene-induced cell death might be pyroptosis. Conclusion: A clinical setting dose of bexarotene induced cell cycle arrest and cell death through caspase-4–mediated pyroptosis in ovarian cancer cell lines. Thus, bexarotene may serve as a novel therapeutic agent for ovarian cancer.

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