Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1140680 (ovarian cancer)
 28,141 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The protooncogene c-kit encodes a transmembrane receptor-type tyrosine kinase which belongs to the beta-PDGER/CSF-1 receptor tyrosine kinase family. The interaction between c-kit receptor and its corresponding ligand, stem cell factor (SCF), has been suggested to be involved in embryogenesis as well as carcinogenesis via the autocrine/paracrine system. In the present study, cancer cell lines and normal/benign/malignant tissues of the human female genital tract were examined for the expression of both c-kit and SCF by Northern blot and immunohistochemical analyses. Two of 16 cell lines showed mRNA expression of both c-kit and SCF, while 2 and 12 cell lines expressed c-kit and SCF, respectively. In tissues, several cases of malignant tumors, including three cervical cancers, one ovarian cancer, and one ovarian immature teratoma, expressed mRNA of both c-kit and SCF. In normal tissues, squamous epithelium expressed SCF immunohistochemically, while c-kit protein was detected only in melanocytes. Some tissues of malignant tumors, one squamous cell carcinoma of the cervix, two small cell carcinomas of the cervix, two serous adenocarcinomas of the ovary, and two immature teratomas of the ovary, expressed both c-kit and SCF proteins immunohistochemically. It is also notable that c-kit protein was expressed only in malignant germ cells of dysgerminomas, while SCF was expressed in the connective tissues surrounding germ cells. The present study suggests that the c-kit/SCF system may play an important role in the carcinogenesis of the female genital tract.
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PMID:Coexpression of the c-kit receptor and the stem cell factor in gynecological tumors. 751 96

Overexpression of the c-erbB-2 proto-oncogene product (p185c-erbB-2) occurs frequently in different types of human cancer and is correlated with a significantly decreased survival in ovarian cancer patients. The effect of c-erbB-2 anti-sense phosphorothioate oligodeoxynucleotides (S-ODNs) was examined on the ovarian cancer cell line SK-OV-3. p185c-erbB-2 levels were specifically reduced by a single-dose application of 5 microM c-erbB-2 anti-sense S-ODNs. This was accompanied by a 60% inhibition of anchorage-dependent cell growth. More strikingly, c-erbB-2 anti-sense S-ODNs almost completely abrogated serum-induced cell spreading. A control of complementary sense oligodeoxynucleotides did not show significant inhibitory effects on cell growth or on cell spreading. The inhibition of cell spreading was imitated by a monoclonal antibody (9G6) targeting the extracellular domain of p185c-erbB-2 and by the tyrosine kinase inhibitor erbstatin. The inhibitory activity of these 2 compounds was lost after a few hours, while the inhibition of serum-induced cell spreading by anti-sense S-ODNs was still present after 24 hr. Our results show that c-erbB-2 anti-sense S-ODNs effectively inhibit the mitogenic and spreading activity of p185c-erbB-2 in ovarian cancer cells. Thus, anti-sense strategies have the potential of providing new strategies for the therapy of ovarian cancer.
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PMID:c-erbB-2 anti-sense phosphorothioate oligodeoxynucleotides inhibit growth and serum-induced cell spreading of P185c-erbB-2-overexpressing ovarian carcinoma cells. 759 Dec 73

Overexpression of HER-2/neu, a 185-kDa tyrosine kinase growth factor receptor, in human ovarian cancers has been correlated with a poor prognosis for survival of the disease. Previous studies have demonstrated that dexamethasone (Dex) induces a dose-dependent increase in HER-2/neu mRNA levels in the ovarian cancer cell line SK-OV-3 by stabilizing the HER-2/neu message. We extended these studies to test whether estrogen (Es), progesterone (Pr), and Dex were capable of regulating HER-2/neu mRNA levels in the human ovarian cancer cell lines NIH:OVCAR-3, SW 626, OVCA 433, and Caov-3. Southern blotting demonstrated that all four cell lines contained a single copy of the 12.5-kb HER-2/neu gene. Blotting techniques demonstrated low to barely detectable levels of HER-2/neu mRNA and protein in these cell lines. To determine whether steroids regulated HER-2/neu expression, all four ovarian cancer cell lines were cultured in the presence of 1 x 10(-7) M Es, Pr, or Dex and Northern blotting was completed. Unlike SK-OV-3 cells, the cell lines tested did not respond to the steroid treatments with alterations in their HER-2/neu mRNA levels. In conclusion, neither Es, Pr, nor Dex regulates HER-2/neu mRNA levels in NIH:OVCAR-3, SW 626, OVCA 433, and Caov-3 ovarian cancer cells. Future therapeutic manipulations of HER-2/neu should not involve hormonal intervention.
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PMID:Steroid hormonal independence of HER-2/neu mRNA expression in four human ovarian carcinoma cell lines. 783 82

Amplification of erbB-2 gene and overexpression of gp185erbB-2 gene product is found in approximately one-third of primary human breast and ovarian cancer. Overexpression of gp185erbB-2 was recently found in human papillary thyroid carcinomas, but not in thyroid follicular carcinomas or adenomas. The erbB-2 gene encodes a cell surface growth factor receptor with intrinsic tyrosine kinase activity. Wild type human erbB-2 has been shown to act as a potent oncogene when overexpressed in mouse fibroblasts. To test whether overexpression of normal human erbB-2 gene can transform epithelial differentiated rat thyroid cells, these cells were infected with a recombinant retroviral expression vector containing the erbB-2 protooncogene. Rat thyroid cells expressing high levels of gp185erbB-2 do not display a fully transformed and tumorigenic phenotype. However, the isolated cell clones that overexpress gp185erbB-2, show changes in their growth properties if compared to normal thyroid cells, since they can grow in absence of thyrotropin, the main growth factor controlling thyroid cell proliferation in vitro, and do not respond to the growth inhibitory effect of transforming growth factor beta.
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PMID:Loss of thyrotropin regulation and transforming growth factor beta-induced growth arrest in erbB-2 overexpressing rat thyroid cells. 810 49

More fundamental understanding of cell growth regulation will provide novel approaches for detecting, preventing, and treating different cancers. Activation of protooncogenes or loss of tumor-suppressor genes can have both prognostic and therapeutic importance. In epithelial ovarian cancer, poor prognosis is associated with continued expression or overexpression of tyrosine kinase growth factor receptors p170EGFR, p165fms, and p185erbB-2. Over-expression of erbB-2 (HER-2/neu) by breast and ovarian cancers already permits effective targeting of antibodies and immunotoxins. Ultimately, molecular analysis of individual cancers will guide the application of specific therapies to inhibit activated oncogenes or restore the function of tumor-suppressor genes. Circulating growth factors, oncogene products, and tumor-associated antigens may provide markers for earlier detection of some cancers. In epithelial ovarian cancer, concentrations of CA 125 can be increased 1-5 years before clinical diagnosis, and approximately 50% of patients with stage I disease have had an abnormal CA 125 concentration. Combining CA 125 with two novel markers--OVX1 and M-CSF--has retrospectively detected > 98% of stage I ovarian cancers. Although the specificity of the three markers is insufficient for cost-effective screening, serum tests for them could prompt the performance of transvaginal sonography, substantially decreasing the number of sonograms required. Genetic markers in the germ line of patients at increased risk for certain cancers will almost certainly influence strategies for prevention or detection. In familial breast, and ovarian cancer, a locus on chromosome 17q tracks risk of cancer in a fraction of kindreds. How often germline abnormalities will be detected in patients with apparently sporadic cancer remains to be determined.
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PMID:Perspectives on the future of cancer markers. 822 57

The HER-2/neu proto-oncogene encodes a 185 kDa transmembrane receptor tyrosine kinase with significant sequence homology to other members of the class I receptor tyrosine kinase family. The HER-2/neu gene is amplified and/or overexpressed in 25%-30% of human breast and ovarian cancers, and overexpression of the receptor is associated with poor prognosis. Tyrosine phosphorylation and activation of the HER-2 receptor lead to activation of specific signal transduction pathways in breast and ovarian cancer cells, including the ras/MAP kinase cascade, phosphatidylinositol 3-kinase, and phospholipase C-gamma. HER-2/neu signal transduction pathways ultimately converge on the cell nucleus, where the expression of diverse genes is induced after activation of the receptor. A more complete understanding of HER-2/neu signal transduction pathways may allow the development of specific therapeutics for the treatment of those human breast and ovarian cancers containing this alteration.
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PMID:HER-2/neu signal transduction in human breast and ovarian cancer. 900 17

We have reported that human ovarian-carcinoma cell lines express high-affinity IL-4 receptor. Since IL-4R has been hypothesized to share a chain with IL-13R, we investigated whether ovarian cancer cells express IL-13 receptor. In the present study, we report that the ovarian-carcinoma cell lines IGROV-1 and PA-1 express varying numbers of high-affinity IL-13 receptors. Furthermore, IL-13 inhibited the binding of IL-4 on both ovarian-carcinoma cell lines, while IL-4 did not inhibit IL-13 binding on IGROV-1 cell line. IL-13 and IL-4 induced the phosphorylation of JAK1, JAK2 and Tyk2 Janus kinases in PA-1 cells. In contrast, JAK3 tyrosine kinase was expressed in PA-1 cells, but IL-4 or IL-13 did not augment its phosphorylation. In IGROV-1 cells, Tyk2 was constitutively phosphorylated and this phosphorylation was augmented by IL-4 or IL-13. JAK1 and JAK2 but not JAK3 were expressed but only JAK2 was faintly phosphorylated in response to either IL-13 or IL-4 respectively. IRS (insulin-receptor substrate)-1 and IRS-2 were also phosphorylated constitutively in both ovarian cancer cell lines examined, but only the phosphorylation of IRS-1 was augmented in response to IL-4 or IL-13. STAT6 was phosphorylated and activated in response to IL-4 and IL-13 in all cell lines examined. Our results demonstrate that ovarian cancer cell lines may express 2 types of IL-13R and the IL-13- or IL-4-induced signaling patterns may be slightly different in each type of receptor.
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PMID:Human ovarian-carcinoma cell lines express IL-4 and IL-13 receptors: comparison between IL-4- and IL-13-induced signal transduction. 900 65

Endothelin 1 (ET-1) is produced in ovarian cancer cell lines and has been shown to act through ET(A) receptors as an autocrine growth factor to promote tumor cell proliferation in vitro. In OVCA 433 cells, the efficacy of ET-1 as a stimulus of [3H]thymidine incorporation was equivalent to that of epidermal growth factor. ET-1 also stimulated the rapid expression of c-fos, an action mediated by ET(A) receptors. The mitogenic action of ET-1 was not mediated by a pertussis toxin-sensitive G protein. An analysis of the effects of inhibition and depletion of protein kinase C (PKC) on mitogenic responses demonstrated that PKC was necessary but not sufficient for maximal stimulation by ET-1. In quiescent OVCA 433 cells, ET-1-induced stimulation of [3H]thymidine incorporation was prevented by two structurally distinct inhibitors of tyrosine kinase, herbimycin A and genistein. These results indicate that both PKC and protein tyrosine kinase participate in ET-1-stimulated mitogenic signaling. ET-1 rapidly stimulated tyrosine phosphorylation of several cellular proteins, among which p125FAK and p42 mitogen-activated protein kinase were identified. The additivity between the potent mitogenic actions of ET-1 and epidermal growth factor is consistent with the independence of their signal transduction pathways in ovarian cancer cells. These findings also indicate that intracellular signaling between the ET(A) receptor and a yet unidentified tyrosine kinase is involved in the mitogenic response to ET-1.
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PMID:Activation of mitogenic signaling by endothelin 1 in ovarian carcinoma cells. 910 18

"Optimal" chemotherapy for advanced ovarian cancer has constantly evolved over the last 2 decades through the conduct of prospective randomized clinical trials. Because 3 such important trials have recently disclosed provocative results there are reasons to believe in the emergence of new "standard" treatment approaches for this disease towards the end of this century. 1) The Intergroup trial found a survival advantage for intraperitoneal cisplatin as compared to intravenous cisplatin following optimal debulking surgery. 2) In the EORTC-GCCG trial, which recruited patients with bulky disease at completion of primary surgery, survival was prolonged when interval debulking surgery was performed after 3 cycles of chemotherapy. 3) Paclitaxel-cisplatin was associated with a marked survival advantage in comparison with cisplatin-cyclophosphamide in the GOG trial, which enrolled suboptimally debulked patients. These trials clearly have important implications for the future management of ovarian cancer patients and from a health economy point of view: for these reasons, two of them (2 + 3) have been repeated by other groups, and results of these confirmatory trials should be available soon. There are a number of new treatment options for "Platinum-resistant" patients including docetaxel, topotecan, gemcitabine, oxaliplatin: but none of them is "optimal". An active search for new drugs in this setting remains a high priority. Finally, with the expanding knowledge of the molecular biology of cancer in general and ovarian cancer in particular, one can now start thinking of new molecular targets for treatment intervention including transmembrane tyrosine kinase growth factor receptors, matrix metalloproteinases, the vascular endothelial growth factor and so on....
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PMID:[Optimal therapeutic strategies in ovarian epithelial cancer in 1997]. 941 42

The 4-[(3-bromophenyl)amino]pyrido[3,4-d]pyrimidine PD 158780 is a very potent in vitro inhibitor of the tyrosine kinase activity of the epidermal growth factor receptor (EGFR) (IC50 0.08 nM), and other members of the erbB family, by competitive binding at the ATP site of these signal transduction enzymes. A series of analogues of PD 158780 bearing solubilizing functions off the 6-methylamino substituent were prepared by reaction of the 6-fluoro derivatives with appropriate amine nucleophiles. These were evaluated for their ability to inhibit the tyrosine phosphorylating action of EGF-stimulated full-length EGFR enzyme and for inhibition of autophosphorylation of the EGFR in A431 human epidermoid carcinoma cells in culture. The most effective analogues were those bearing weakly basic substituents through a secondary amine linkage, which proved water-soluble (> 10 mM) and potent (IC50S generally < 1 nM). No clear SAR could be discerned for these compounds with respect to amine base strength or the distance of the cationic center from the chromophore, suggesting that 6-substituents are in a favorable area of bulk tolerance in the enzyme binding site. More distinct SAR emerged for the ability of the compounds to inhibit EGFR autophosphorylation in A431 cells, where analogues bearing lipophilic weak bases were preferred. Representative analogues were evaluated for antitumor effectiveness against four in vivo tumor models. Significant in vivo activity was observed in estrogen-dependent MCF-7 breast and A431 epidermoid tumors. Marginal activity was seen in an EGFR-transfected tumor model, suggesting that while this cell line requires EGF for clone formation in soft agar, other growth factors may be able to replace EGF in vivo. Also, no activity was seen against the SK-OV-3 ovarian cancer model, which is known to express other EGF receptor family members (although it is not clear whether these are absolutely required for growth in vivo). While substantial growth delays were seen in A431 and MCF-7 tumor models, the treated tumors remained approximately the same size throughout therapy, suggesting that the compounds are cytostatic rather than cytotoxic under these test conditions. It remains to be determined if more prolonged therapy has cytotoxic effects in vivo, resulting in net tumor cell kill.
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PMID:Tyrosine kinase inhibitors. 14. Structure-activity relationships for methylamino-substituted derivatives of 4-[(3-bromophenyl)amino]-6-(methylamino)-pyrido[3,4-d]pyrimidine (PD 158780), a potent and specific inhibitor of the tyrosine kinase activity of receptors for the EGF family of growth factors. 951 2


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