Normal Human Ovarian Epithelial Cells Research Articles

Profiling estrogen-regulated gene expression changes in normal and malignant human ovarian surface epithelial cells

Estrogens regulate normal ovarian surface epithelium (OSE) cell functions but also affect epithelial ovarian cancer (OCa) development. Little is known about how estrogens play such opposing roles. Transcriptional profiling using a cDNA microarray containing 2400 named genes identified 155 genes whose expression was altered by estradiol-17beta (E2) in three immortalized normal human ovarian surface epithelial (HOSE) cell lines and 315 genes whose expression was affected by the hormone in three established OCa (OVCA) cell lines. All but 19 of the genes in these two sets were different. Among the 19 overlapping genes, five were found to show discordant responses between HOSE and OVCA cell lines. The five genes are those that encode clone 5.1 RNA-binding protein (RNPS1), erythrocyte adducin alpha subunit (ADD1), plexin A3 (PLXNA3 or the SEX gene), nuclear protein SkiP (SKIIP), and Rap-2 (rap-2). RNPS1, ADD1, rap-2, and SKIIP were upregulated by E2 in HOSE cells but downregulated by estrogen in OVCA cells, whereas PLXNA3 showed the reverse pattern of regulation. The estrogen effects was observed within 6-18 h of treatment. In silicon analyses revealed presence of estrogen response elements in the proximal promoters of all five genes. RNPS1, ADD1, and PLXNA3 were underexpressed in OVCA cell lines compared to HOSE cell lines, while the opposite was true for rap-2 and SKIIP. Functional studies showed that RNPS1 and ADD1 exerted multiple antitumor actions in OVCA cells, while PLXNA3 only inhibited cell invasiveness. In contrast, rap-2 was found to cause significant oncogenic effects in OVCA cells, while SKIIP promotes only anchorage-independent growth. In sum, gene profiling data reveal that (1) E2 exerts different actions on HOSE cells than on OVCA cells by affecting two distinct transcriptomes with few overlapping genes and (2) among the overlapping genes, a set of putative oncogenes/tumor suppressors have been identified due to their differential responses to E2 between the two cell types. These findings may explain the paradoxical roles of estrogens in regulating normal and malignant OSE cell functions.

Inflammation-associated gene expression is altered between normal human ovarian surface epithelial cells and cell lines derived from ovarian adenocarcinomas

Ovulation is believed to contribute to the development of ovarian cancers that derive from the ovarian surface epithelium (OSE). The process of ovulation is synonymous with inflammation and inflammatory cytokines such as interleukin-1α (IL-1α) have recently been shown to induce both inflammatory and anti-inflammatory responses in human OSE (HOSE) cells. In this study we directly compared levels of IL-1α-induced gene expression by analysing the levels of 11β-hydroxysteroid dehydrogenase (11βHSD) types 1 (11βHSD-1) and 2 (11βHSD-2), cyclooxygenase-2 (COX-2), IL-1 receptor (IL-1R) and glucocorticoid receptor α (GRα) mRNA between normal HOSE cells and cell lines derived from poorly differentiated (SKOV-3, BG-1, PEO-4) and well-differentiated (PEO-14) ovarian adenocarcinoma. In HOSE cell cultures, and to a lesser extent PEO-14 cells, the basal mRNA levels of COX-2 and 11βHSD-1 were relatively high and further shown to be induced in response to IL-1α (for HOSE cells; >20-fold, P<0.05 and PEO-14 cells; >3fold, P<0.05). However, whereas HOSE cells expressed a low level of 11βHSD-2 mRNA that was only mildly responsive to IL-1α (1.3-fold, P<0.001), all cell lines exhibited a higher basal level of 11βHSD-2 mRNA that was in some cases further stimulated in PEO-4 cells (five-fold; P<0.05) or suppressed in SKOV-3 cells (two-fold; P<0.01) in response to IL-1α. All cells tested expressed IL-1R and, with the exception of BG-1, GRα. These results indicate that cell lines derived from ovarian cancers have lost the ability to respond normally to inflammatory cytokines such as IL-1α. The finding that normal OSE cells, in contrast to cell lines derived from patients with ovarian adenocarcinoma, abundantly express 11βHSD-1 mRNA but are essentially devoid of 11βHSD-2 mRNA supports the concept that the pattern of 11βHSD isoform gene expression is a defining feature of neoplastic cellular transformation, which might have particular relevance to the ovary.

Estrogen-induced loss of progesterone receptor expression in normal and malignant ovarian surface epithelial cells

While estrogens are suspected risk factors for epithelial ovarian cancer (OCa), progesterone (P4) has been shown to exert protective effects. The biological actions of P4 in target cells are mediated by progesterone receptors (PRs) that exist principally as A- and B-isoforms. We observed overexpression of PR-A and PR-B protein in two lines of OCa cells when compared to two lines of nontumorigenic, normal human ovarian surface epithelial (HOSE) cells. Treatment of HOSE or OCa cells with estrone or 17beta-estradiol at 10(-8) M for a period of 72 h induced significant loss of PR-A and PR-B mRNA and protein expression, with the regulation primarily controlled at the transcriptional level. In contrast, breast cancer cells (line MCF-7) exposed to estrogens upregulated PR-A and PR-B expression. Of significance, both the inhibitory and stimulatory actions of estrogens were blocked by the specific ER-antagonist ICI 182,780 (ICI, 10(-5) M), confirming estrogen specificity. Co-treatment of estrogen-exposed HOSE, OCa, and MCF-7 cell lines with inhibitors of type 1- and type 2-17beta hydroxysteroid dehydrogenase did not affect the previously observed changes in PR expression, suggesting that the action of each estrogen is direct and not mediated via conversion to its metabolic counterpart. Green fluorescence protein (GFP)-PR-A and GFP-PR-B were localized in the cytoplasmic compartment of untreated HOSE cells and translocated to the nucleus after P4 treatment, while both chimera PRs resided in the nuclei of OCa cells in a ligand-independent manner. In OCa cell cultures, P4 (10(-6) M), but not RU486 (10(-5) M), induced apoptosis that was blocked by co-treatment with the antiprogestin but enhanced by co-treatment with ICI. In sharp contrast, P4 induced proliferation, while ICI and RU486 caused cell death in MCF-7 cells. In conclusion, this study is first to demonstrate estrogens as negative regulators of PR expression in HOSE/OCa cells and to provide a mechanistic basis upon which to explain the antagonism of estrogens on the anti-OCa action of progestins. It also raises the possibility of using progestin and ICI as a combinational therapy for OCa treatment.

Telomerase Prolongs the Lifespan of Normal Human Ovarian Surface Epithelial Cells Without Inducing Neoplastic Phenotype

The aim of this study was to determine the effects of exogenous expression of the catalytic subunit of telomerase (hTERT) on the lifespan, growth characteristics, and tumorigenicity of normal human ovarian surface epithelial (OSE) cells. Low-passage primary cultures of normal human OSE cells were transfected with hTERT and the resulting cell lines were characterized. The ectopic expression of hTERT stabilized the telomeres of the OSE cultures above 8 kb. The hTERT-transfected OSE cell lines grew beyond the normal lifespan seen in OSE cells and propagated in culture for more than 40 passages before senescing. Moreover, the hTERT-transfected cells demonstrated extensive proliferative capacity as evidenced by their ability to continuously grow even when seeded at low dilutions. The morphologic features and normal differentiation patterns seen in normal OSE cells were likewise retained by the hTERT-transfected cells. In addition, the cultures remained responsive to physiologic concentrations of epidermal growth factor and transforming growth factor-beta. Changes associated with neoplastic transformation like anchorage-independent growth, tumorigencity and karyotypic instability were not observed. We were able to show that the ectopic expression of hTERT in normal human OSE: 1) resulted in cultures with greater growth potential and longer lifespan and 2) did not induce a transformed phenotype previously seen in viral oncogene-transfected OSE cells. The established cell lines would not only provide sufficient material for comprehensive studies to investigate the normal physiology of OSE cells, but could also help in the understanding of the early steps of ovarian carcinogenesis.

Telomere-mediated mitotic disturbances in immortalized ovarian epithelial cells reproduce chromosomal losses and breakpoints from ovarian carcinoma.

Ovarian carcinomas (OCs) often exhibit highly complex cytogenetic changes. Abnormal chromosome segregation at mitosis is one potential mechanism for genomic rearrangements in tumors. In this study, OCs were demonstrated to have dysfunctional short telomeres, anaphase bridging, and multipolar mitoses with supernumerary centrosomes. When normal human ovarian surface epithelial (HOSE) cells were transfected with human papilloma virus 16 e6/e7 genes and subsequently driven into telomere crisis, the same set of mitotic disturbances occurred in a distinct sequence, initiated by telomere dysfunction, followed by anaphase bridging, and then supernumerary centrosomes and multipolar mitoses. The anaphase bridges resolved either by kinetochore-spindle detachment, corresponding to whole-chromosome losses in the HOSE karyotypes, or by extensive fragmentation of intercentromeric DNA sequences, corresponding to a high frequency of pericentromeric rearrangements. At later passages, the high degree of instability at telomere crisis was moderated by telomerase expression and centrosome coalescence, ultimately leading to a level of mitotic instability that was highly similar to that in OC cell lines and to complex karyotypes that were similar to those observed in high-grade OCs. This suggests that a significant proportion of the structural chromosome changes and genomic losses in OC are caused by a specific sequence of mitotic disturbances triggered by telomere crisis. That the model did not produce any of the whole-chromosome gains observed in OC indicates that these changes develop through a different mechanism.

P150(Sal2) is a p53-independent regulator of p21(WAF1/CIP).

p150(Sal2), a vertebrate homologue of the Drosophila melanogaster homeotic transcription factor Spalt, has previously been shown to be a binding target of the polyomavirus large T antigen. p150(Sal2) acts as an inhibitor of viral DNA synthesis, and the binding of p150(Sal2) by large T overcomes this inhibition. The present study focuses on the effects of p150(Sal2) on the growth and survival of ovarian carcinoma (OVCA) cells that are deficient in expression of p150(Sal2) and of normal established human ovarian surface epithelial (HOSE) cells which abundantly express the protein. Transient expression of exogenous p150(Sal2) in OVCA cells that show little or no endogenous expression resulted in inhibition of DNA synthesis and colony formation and in increased apoptosis. OVCA cells stably transfected and expressing physiological levels of p150(Sal2) showed reduced tumorigenicity accompanied by increased expression of p21(WAF1/CIP1) (p21) and BAX. Conversely, reduction of endogenous levels of p150(Sal2) in HOSE resulted in reduced p21 expression and increased DNA synthesis. p150(Sal2) bound to the p21 promoter adjacent to the known p53 binding sites and stimulated transcription in the absence of p53. We propose that p150(Sal2), acting in part as a p53-independent regulator of p21 and BAX, can function in some cell types as a regulator of cell growth and survival.

Profiling follicle stimulating hormone-induced gene expression changes in normal and malignant human ovarian surface epithelial cells.

Epidemiological data have implicated the pituitary gonadotropin follicle stimulating hormone (FSH) as both a risk factor for and a protective agent against epithelial ovarian cancer. Yet, little is known about how this hormone could play such opposing roles in ovarian carcinogenesis. Complementary DNA microarrays containing 2400 named genes were used to examine FSH-induced gene expression changes in ovarian cancer (OC) and immortalized normal human ovarian surface epithelial (HOSE) cell lines. Two-way t-statistics analyses of array data identified two distinct sets of FSH-regulated genes in HOSE and in established OC cell lines established from patients (OVCA cell lines). Among the HOSE cell lines, FSH increased expression of 57% of the 312 genes and downregulated 43%. In contrast, FSH diminished expression of 92% of the 177 genes in the OVCA cell lines. All but 18 of the genes affected by FSH in HOSE cell lines were different from those altered in OVCA cell lines. Among the 18 overlapping genes, nine genes exhibited the same direction of change following FSH challenge, while the other nine showed discordance in response between HOSE and OVCA cell lines. The FSH-induced differential expression of seven out of nine genes was confirmed by real-time RT-PCR. Gene-specific antisense oligonuleotides (ODNs) were used to inhibit the expression of genes encoding GTPase activating protein (rap1GAP), neogenin, and restin in HOSE and OVCA cells. Antisense ODNs to neogenin and restin, but not an antisense ODN to rap1GAP, were effective in inhibiting OVCA cell growth, diminishing proliferating cell nuclear antigen expression, and increasing caspase 3 activities. Furthermore, the ODN to rap1GAP was further shown to be ineffective in altering migration properties of OVCA cell lines. HOSE cell proliferation was not affected by treatment with any of the antisense ODNs. In summary, gene profiling data reveal for the first time that FSH may exert different biological actions on OVCA cells than on HOSE cells, by differential regulation of a set of putative oncogenes/tumor suppressors. Specifically, neogenin and restin were found to exhibit proproliferation/survival action on OC cells.

Combined TRAIL and Bax gene therapy prolonged survival in mice with ovarian cancer xenograft.

We evaluated the antitumor activity of the Bax gene and green fluorescent protein/tumor necrosis factor-related apoptosis-inducing ligand (GFP/TRAIL) fusion gene driven by the human telomerase reverse transcriptase promoter both separately and combined in the human ovarian cancer lines SKOV3ip and DOV13 and human lung cancer line H1299. In vitro study showed that both TRAIL- and Bax-expressing vectors elicited significant cell killing in H1299 and SKOV3ip cells, but only the GFP/TRAIL gene elicited significant cell killing in DOV13 cells. Combined TRAIL and Bax therapy also produced more profound cell killing in SKOV3ip and H1299 cells, but not DOV13 cells without escalation of the vector doses. To further evaluate the combined effects of Bax and TRAIL, abdominally spread tumors were established in nude mice via intraperitoneal inoculation of SKOV3ip cells followed by that of adenoviral vectors. Tumor growth, ascites formation, survival duration and toxicity were evaluated after treatment. We found that treatment using the Bax- or TRAIL-expressing vector alone significantly suppressed tumor growth and ascites formation, and prolonged animal survival when compared with that of using PBS or a control vector. Combined TRAIL and Bax therapy further prolonged survival significantly when compared with therapy using the TRAIL or Bax gene alone. Transgene expression and apoptosis induction were not detected in normal human ovarian epithelial cells in vitro or normal mouse tissues in vivo after intraperitoneal vector administration. Also, liver toxicity was not detected after either treatment. Thus, combined TRAIL and Bax gene therapy may be useful for treatment of abdominally spread tumors.

Reproductive hormone-induced, STAT3-mediated interleukin 6 action in normal and malignant human ovarian surface epithelial cells.

Reproductive hormones are associated with risk for epithelial ovarian cancer. To determine the effect of such hormones on the activation of interleukin 6 (IL-6)/STAT3 (signal transducer and activator of transcription-3) signaling, which may be involved in ovarian cancer, we investigated the status of STAT3, IL-6, and its receptor in immortalized human ovarian surface epithelial (HOSE) and ovarian cancer (OVCA) cell lines. Two immortalized HOSE cell lines and two OVCA cell lines were cultured with gonadotropins, sex steroid hormones, and/or IL-6, alone or with specific inhibitors or IL-6-neutralizing antibodies. Expression of IL-6, the IL-6 receptor alpha chain (IL-6Ralpha), and phosphorylated and unphosphorylated STAT3 messenger RNAs (mRNAs) and proteins in all cells was determined. Cell proliferation and soft-agar colony formation were assessed. STAT3 activity was investigated in OVCA cells transfected with a dominant negative STAT3 (Dn-STAT3), wild-type STAT3, or an empty control vector. All statistical tests were two-sided. Levels of IL-6 mRNA and protein increased in all cells treated with follicle-stimulating hormone (FSH), luteinizing hormone (LH), 17beta-estradiol, or estrone but increased only in OVCA cells treated with testosterone and 5alpha-dihydrotestosterone. For all lines, IL-6 antibodies partially inhibited hormone-stimulated cell proliferation but completely inhibited IL-6-enhanced cell proliferation. IL-6 induced STAT3 phosphorylation and activation in HOSE cells; STAT3 was constitutively activated in OVCA cells. Higher levels of IL-6Ralpha and STAT3 transcription factors were observed in OVCA cells than in HOSE cells. After transfection, Dn-STAT3 suppressed endogenous STAT3 and inhibited all forms of IL-6-stimulated OVCA cell proliferation (OVCA 429 cells, P<.001; OVCA 432 cells, P<.006), whereas wild-type STAT3 enhanced HOSE cell proliferation (wild-type STAT3 at 0.5 microg/mL in HOSE 306 cells, P<.002; STAT3 at 1.0 microg/mL in HOSE 306 or both concentrations of wild-type STAT3 in HOSE 642 cells, P<.001). The IL-6/STAT3 signaling pathway may mediate FSH-, LH-, and estrogen-stimulated HOSE cell proliferation. Increased IL-6Ralpha expression and constitutive STAT3 activation may be associated with ovarian cancer.

WWOX: a candidate tumor suppressor gene involved in multiple tumor types.

We previously reported the construction of a P1-derived artificial chromosome (PAC) contig encompassing a set of homozygous deletions of chromosome 16q23-24.1 found in primary ovarian tumor material and several tumor cell lines. Using these PAC clones in a cDNA selection experiment, we have isolated a Sau3A fragment homologous to the WWOX transcript (GenBank accession no. ) from normal human ovarian surface epithelial (HOSE) cells. We demonstrate the homozygous deletion of WWOX exons from ovarian cancer cells and three different tumor cell lines. We also identify an internally deleted WWOX transcript from a further primary ovarian tumor. In three of these samples the deletions result in frameshifts, and in each case the resulting WWOX transcripts lack part, or all, of the short chain dehydrogenase domain and the putative mitochondrial localization signal. Sequencing revealed several missense polymorphisms in tumor cell lines and identified a high level of single nucleotide polymorphism (SNP) within the WWOX gene. This evidence strengthens the case for WWOX as a tumor suppressor gene in ovarian cancer and other tumor types.

Analysis of p73 in human borderline and invasive ovarian tumor.

p73 is a novel gene that has high sequence homology and similar gene structure to the tumor suppressor gene p53. We analysed p73 in seven ovarian carcinoma cell lines and a total of 63 human borderline and invasive ovarian tumor samples. Loss of heterozygosity at this locus was observed in 50% of invasive tumors but in none of the borderline tumors. Biallelic expression of the gene was observed in the heterozygous tumor tissues. Direct sequencing and single-strand conformation polymorphism analyses of the p73 cDNA sequence homologous to the highly mutatable region of p53 did not reveal any mutations. When compared to the primary cultures of normal human ovarian surface epithelial cells and immortalized cell lines, four of the seven ovarian carcinoma cell lines, 71% of the invasive tumors, and 92% of the borderline tumor tissues express elevated levels of p73 transcript. Except for the OVCA3 cell line, Western blot analysis of the nuclear extracts prepared from the cell lines showed concordant levels of p73 protein. Our analysis also demonstrated the expression of a spliced variant of p73 transcript with the omission of exon 2 solely in the cancer cell lines and invasive tumor tissues. This exon 2-spliced transcript would give rise to a truncated p73 protein without the N-terminal transactivation domain. In reminiscence of the dominant negative phenotype of the N-terminal truncated variants of another p53-related gene, p63, the expression of the truncated p73 variant form in ovarian tumors may play an important role in the pathogenesis of ovarian cancer.

Biologic effects of heregulin/neu differentiation factor on normal and malignant human breast and ovarian epithelial cells.

The heregulins are a family of ligands with ability to induce phosphorylation of the p185HER-2/neu receptor. Various investigators have reported a variety of responses of mouse and human breast and ovarian cells to this family of ligands including growth stimulation, growth inhibition, apoptosis and induction of differentiation in cells expressing the HER-2/neu receptor. Some of the disparity in the literature has been attributed to variations in the cell lines studied, ligand dose applied, methodologies utilized or model system evaluated (i.e. in vitro or in vivo). To evaluate the effects of heregulin on normal and malignant human breast and ovarian epithelial cells expressing known levels of the HER-2/neu receptor, this report presents the use of several different assays, performed both in vitro and in vivo, in vitro proliferation assays, direct cell counts, clonogenicity under anchorage-dependent and anchorage-independent conditions, as well as the in vivo effects of heregulin on human cells growing in nude mice to address heregulin activity. Using a total of five different biologic assays in nine different cell lines, across two different epithelia and over a one log heregulin dose range, we obtained results that clearly indicate a growth-stimulatory role for this ligand in human breast and ovarian epithelial cells. We find no evidence that heregulin has any growth-inhibitory effects in human epithelial cells. We also quantitated the amount of each member of the type I receptor tyrosine kinase family (RTK I, i.e. HER-1, HER-2, HER-3 and HER-4) in the cell lines employed and correlated this to their respective heregulin responses. These data demonstrate that HER-2/neu overexpression itself affects the expression of other RTK I members and that cells expressing the highest levels of HER-2/neu have the greatest response to HRG.

Gap junctional intercellular communication and connexin43 expression in human ovarian surface epithelial cells and ovarian carcinomas in vivo and in vitro.

Gap junctional intercellular communication (GJIC) and the expression of gap junction proteins (connexins) are frequently decreased in neoplastic cells and have been increased by cAMP and retinoids. GJIC and connexin expression were investigated in early passage normal human ovarian surface epithelial (HOSE) cells, human ovarian adenocarcinoma cell lines (CaOV-3, NIH:OVCAR-3, SK-OV-3 and SW626) and surgical specimens of human serous cystadenocarcinomas. We hypothesized that GJIC and connexin expression would be decreased in neoplastic cells and would be increased by cAMP and retinoic acid. Cultured HOSE cells exhibited extensive fluorescent dye-coupling and connexin43 (Cx43) expression; other connexins were not detected. The ovarian adenocarcinoma cell lines had little dye-coupling or connexin expression. Deletions and rearrangements of the Cx43 gene were not detected by Southern blotting in the carcinoma lines. N6, 2'-O-dibutyryladenosine 3',5'-cyclic monophosphate and all-trans-retinoic acid inhibited cell proliferation, but did not enhance GJIC or Cx43 expression. Surface epithelial cells of benign ovaries expressed Cx43, but this expression was barely detectable in ovarian serous cystadenocarcinomas. Thus, normal HOSE cells had extensive GJIC and Cx43 expression whereas ovarian carcinoma cells had less and cAMP and retinoic acid did not change these, although both agents inhibited cell growth.

Differential expression of NF1 type I and type II isoforms in sporadic borderline and invasive epithelial ovarian tumors.

The NF1 gene, a putative tumor suppressor gene, contains a GAP related domain (GRD) which accelerates hydrolysis of ras-bound GTP to GDP, thereby converting the ras oncogene from its active to inactive form. Two forms of the NF1 GRD transcript (Type I and Type II) are differentially expressed in neuroectodermal tumor tissue relative to differentiated neural cells, and in gastric cancer cell lines relative to normal stomach mucosa. We measured relative expression of NF1 Type II and Type I isoforms in cultured normal and malignant human ovarian surface epithelial cells(HOSE) and in invasive and borderline ovarian tumor tissue. We demonstrated an 11-fold increase in Type II:Type I ratio in 7 HOSE cultures relative to eight ovarian cancer cell lines. Our findings indicate a significant decrease in Type II isoform expression and increase in Type I expression in ovarian cancer cells and tumor tissue relative to HOSE cells. We also demonstrate an increase in Type II:Type I ratio, and a decrease in cell proliferation rate in three ovarian cancer cell lines on treatment with retinoic acid. We propose that differential expression of the NF1 Type I and Type II isoforms is related to cellular differentiation in ovarian epithelial cancer and strategies based on alteration in NF1 isoform expression may have therapeutic potential in ovarian malignancies.

DOC-2, a candidate tumor suppressor gene in human epithelial ovarian cancer.

Using RNA fingerprinting (RAP) strategy and Northern blot analysis, we identified a differentially expressed sequence DOC-2 which is detectable in all normal human ovarian surface epithelial (HOSE) cell cultures but not in ovarian cancer cell lines and tissues. Subsequent cloning of DOC-2 from a cDNA library generated from the HOSE cells was carried out using the 3' and 5' RACE approach. A 3268 base pair full length cDNA of DOC-2 was isolated and sequenced. The predicted protein has a length of 770 amino acids. Homology search of all NCBI sequences indicated that the amino acid sequence of DOC-2 shares 93% homology with the mouse p96/mDab2 phosphoprotein and has a phosphotyrosine interacting domain (PID) and multiple SH3 binding motifs. Chromosomal localization by FISH showed that the DOC-2 gene is located on 5p13. Western blot analysis showed that the 105 kDa DOC-2 protein was down-regulated in all the carcinoma cell lines. In-situ immunohistochemistry performed on normal ovaries, and benign, borderline and invasive ovarian tumor tissues showed down regulation of DOC-2 protein particularly in serous ovarian tumor tissues. When DOC-2 was transfected into the ovarian carcinoma cell line SKOV3, the stable transfectants showed significantly reduced growth rate and ability to form tumors in nude mice. These data suggest that down-regulation of DOC-2 may play an important role in ovarian carcinogenesis.

Applying the herpes simplex virus thymidine kinase/ganciclovir approach to ovarian cancer: an effective in vitro drug-sensitization system.

Ovarian cancer is a major clinical problem with no rewarding treatment protocol currently available. In other malignancies transfer of the herpes simplex virus thymidine kinase (HSV-tk) gene into tumor cells using a viral vector followed by administration of ganciclovir (GCV) provides a potentially effective strategy for treatment. In this work human ovarian epithelial cancer cell lines were infected with a recombinant adenoviral vector expressing the HSV-tk (AdRSV-tk) and were rendered sensitive to doses of GCV that were 100-200 times less than for untransfected cells. A strong bystander effect was noted with significant killing at a ratio of infected:uninfected cells of only 1:20 and maximal killing at 1:3. Normal human ovarian surface epithelial cells were also highly sensitive to the AdRSV-tk/GCV system. This study demonstrates the potential efficacy of the HSV-tk/GCV approach in ovarian cancer gene therapy.

Different effects of interferons, interleukin-1β and tumor necrosis factor-α in normal (OSE) and malignant human ovarian epithelial cells

Different effects of interferons, interleukin-1β and tumor necrosis factor-α in normal (OSE) and malignant human ovarian epithelial cells

Different effects of interferons, interleukin-1beta and tumor necrosis factor-alpha in normal (OSE) and malignant human ovarian epithelial cells.

Ovarian cancer arises mostly from the ovarian surface epithelium. The aim of our study was to compare the effects of cytokines in ovarian surface epithelial (OSE) cells and in ovarian carcinoma cells. Proliferation and expression of surface antigens (CA-125 and classes I and II antigens of the major histocompatibility complex [MHC]) were measured in OSE cells obtained from 7 different patients and 7 ovarian carcinoma cell lines. Proliferation of OSE cells remained unaffected by interferon (IFN)-alpha or IFN-gamma, whereas interleukin-1 (IL-1) and tumor necrosis factor (TNF) increased cell growth. Proliferation of ovarian carcinoma cells was reduced by both types of IFN as well as TNF but was not affected by IL-1. Expression of the tumor marker CA-125 was increased by IFN-gamma in ovarian carcinoma cells but not by any other treatment. None of the cytokines affected CA-125 surface expression in OSE cells. Expression of MHC-I was augmented in OSE and in carcinoma cells by both IFNs but not by the other cytokines. Both types of cell were negative for MHC-II, but IFN-gamma induced its expression in both OSE and carcinoma cells. Significant concentrations of the cytokines evaluated here have been measured in blood and follicular fluid by several authors. The different actions of these cytokines in OSE and carcinoma cells could therefore be important in understanding the role of such molecules in the regulation of physiological and pathological processes in the ovary, such as ovulation or malignant proliferation.

Regulation of normal and malignant human ovarian epithelial cell adhesion to the extracellular matrix.

Regulation of normal and malignant human ovarian epithelial cell adhesion to the extracellular matrix.

BRCA 1 expression in normal and malignant human ovarian epithelial cells

BRCA 1 expression in normal and malignant human ovarian epithelial cells