Synergistic antiproliferative activity of quercetin and cisplatin on ovarian cancer cell growth

It has been demonstrated that the flavonoid quercetin (3,3',4',5-7-pentahydroxyflavone) (Q) inhibits the growth of several cancer cell lines and that the antiproliferative activity of this substance is mediated by a so-called type II estrogen binding site (type II EBS). We investigated the effects of quercetin and cisplatin (CDDP) alone and in combination on the proliferation of the ovarian cancer cell line OVCA 433. Both drugs exhibited a dose-related growth inhibition in a range of concentrations between 0.01 and 2.5 microM and 0.01 and 2.5 micrograms/ml for Q and CDDP respectively. The combination of the two drugs resulted in a synergistic antiproliferative activity. Two other flavonoids tested, i.e., rutin (3-rhamnosylglucoside of quercetin) and hesperidin [7-b rutinoside of hesperetin (3'-5-3-hydroxy-4-methoxyflavone)] were ineffective both alone and in combination with CDDP. Since both rutin and hesperidin do not bind to type II EBS it can be hypothesized that Q synergizes with CDDP by acting through an interaction with these binding sites.     

Cathepsin D in primary squamous laryngeal tumors: correlation with clinico-pathological parameters and receptor status.

Using an immunoradiometric assay, Cathepsin D (Cath D) levels were measured in the cytosol of 23 normal and 39 neoplastic human laryngeal tissues. Scattered Cath D levels (from 2.2 to 17.8 pM/mg protein; median = 7.6) were found in normal mucosa specimens. Cath D concentrations range from 2.0 to 29.3 pM/mg protein (median = 8.5) in laryngeal tumors. When a comparison between Cath D levels in normal and neoplastic tissue specimens from the same patient was done, Cath D levels were significantly higher in laryngeal cancers than in their normal counterparts (P = 0.03). No correlation with clinico-pathological parameters and steroid hormone and epidermal growth factor receptor status was found. Further studies should investigate whether the production of Cath D by laryngeal tumors could have a clinical relevance for this neoplasia.     

Densitometric and morphometric study of immunocytochemical estrogen receptors detection in breast carcinomas.

Immunohistochemical quantitative evaluation of estrogen receptors (ER) detected in tissue sections from 30 breast tumors by monoclonal antibody was performed using a densitometric method. In particular, ER concentration was calculated by nuclear mean optical density (nMOD), while heterogeneity in ER content was calculated by the coefficient of variation (CV) of the nuclear optical density histogram. Tumors which showed more than 60% of positive cells had a mean value of ER-nMOD of 0.116 +/- 0.002 a.u. and of ER-CV of 33.74 +/- 0.68. Tumors which showed 30% to 60% of positive cells had a mean value of ER-nMOD of 0.082 +/- 0.006 a.u. (arbitrary units) and of ER-CV of 36.25 +/- 3.44. Tumors showing less than 30% of positive cells had ER-nMOD of 0.052 +/- 0.009 a.u. and ER-CV of 48.49 +/- 5.61. These results indicate that the greater the concentration the lower the ER heterogeneity within the tumor sample. No significant differences between ER-ICA results, nuclear size and form factors were found.     

Prognostic role of immunosuppressive acidic protein in advanced ovarian cancer

OBJECTIVE: Our purpose was to investigate immunosuppressive acidic protein in the prognostic characterization of advanced ovarian cancer. STUDY DESIGN: Serum levels of immunosuppressive protein were prospectively measured in 80 patients with untreated ovarian carcinoma. To evaluate the prognostic significance of immunosuppressive acidic protein levels, cutoff points were studied every 50 μg/ml between 450 and 1350 μg/ml. RESULTS: Pretreatment immunosuppressive acidic protein levels were not significantly associated with stage, histotype, grade of differentiation, postoperative residual tumor, and response to chemotherapy. The most significant association with survival was observed at a cutoff value of 1100 μg/ml (p = 0.0089). In the univariate analysis for overall survival, International Federation of Gynecology and Obstetrics stage and immunosuppressive acidic protein status were found to have a role in predicting ovarian cancer prognosis. In the multivariate analysis only immunosuppressive acidic protein status was significantly associated with survival. A statistical correlation was found between serum levels and overall survival (p = 0.0104, χ² 6.56), including immunosuppressive acidic protein as a continuous variable. CONCLUSION: Our data suggest that immunosuppressive acidic protein assay is a potentially useful tool in the prognostic characterization of advanced ovarian cancer. (Am J Obstet Gynecol 1996;175:1606-10.)     

Glutathione S-transferase activity in epithelial ovarian cancer: Association with response to chemotherapy and disease outcome

Background: Conflicting data have been reported about the associationbetween glutathione S-transferase (GST), a family of proteins implicated indetoxification of cytotoxic drugs in human ovarian in vitro models, andresponse to chemotherapy and prognosis in ovarian cancer patients. The aim ofthis study was to analyze the possible clinical role of GST activity in alarge series of primary ovarian cancer patients.Patients and methods: The study included a large series of primaryuntreated ovarian cancer patients who underwent cytoreductive surgery andchemotherapy and who were followed up in a single institution. GST activitylevels were assessed in tumor extracts by using a biochemical assay. A cut-offof 250 units of enzymatic activity was chosen according to the receiveroperating characteristics (ROC) curve.Results: GST activity levels were distributed in an asymmetrical manner(median: 266 units; range: 4–918 units) and did not seem to beassociated with stage, histopathological grading, ascites, or residual tumorafter surgery. Higher GST activity levels were found in patients who respondedto chemotherapy (median: 298 units, range: 50–691) than in those whoresponded only partially (median: 227 units, range: 19–747) or not atall to chemotherapy (median: 246 units, range: 4–811) (H = 7.02, P =0.029). Moreover, the percentage of cases with >250 units was significantlyhigher among complete responders (66%) than partial responders(37%) or non-responders (48%) (² = 7.32;P = 0.025). When multivariate analysis, including clinico-pathologicalparameters and GST activity status as predictors of response to chemotherapy,was carried out, residual tumor, stage and GST status retained independentpredictive value. Patients with high GST activity had more favourableprognosis than those with low GST activity. The median PFS was 42 months forpatients with high GST activity compared to 17 months for those with low GSTactivity (P = 0.037). The median overall survival was 72 months forhigh-GST-activity and42 months for low-GST-activity patients (P = 0.043). Substantially similarresults were obtained in the subgroup of stage II–III–IV ovariancancer patients. Multivariate analysis including the clinico-pathologicalparameters and GST activity status was performed in stage III–IV ovariancancer patients: Stage IV disease, residual tumor >2 cm, the presence ofascites and low GST activity status retained independent negative prognosticroles.Conclusion: A direct association between high GST activity and a betterclinical outcome in terms of response to chemotherapy and survival has beenobserved in a large series of primary untreated ovarian cancer patients. Theseresults, which are contrary to the expectations raised by in vitro studies,emphasize the need for caution when translating in vitro-generated hypothesesto the clinical setting.     

Quercetin potentiates the effect of adriamycin in a multidrug-resistant MCF-7 human breast-cancer cell line: P-glycoprotein as a possible target

This study demonstrates that the flavonoid quercetin (Q), a plant-derived compound with low toxicity in vivo, greatly potentiates the growth-inhibitory activity of Adriamycin (ADR) on MCF-7 ADR-resistant human breast cancer cells. The effect of Q was dose-dependent at concentrations ranging between 1 and 10 M. Since ADR resistance in these cells is associated with the expression of high levels of P-glycoprotein (Pgp), we evaluated the effect of Q and related flavonoids of Pgp activity in cytofluorographic efflux experiments with the fluorescent dye rhodamine 123 (Rh 123). Our results indicate that Q and 3-OMe Q (3,4,7-trimethoxyquercetin) but not the 3-rhamnosylglucoside of Q (rutin) inhibit the Pgp pump-efflux activity in a dose-related manner. Moreover, 10 M Q reduces the expression of the immunoreactive Pgp in MCF-7 ADR-resistant cells as evaluated by cytofluorimetric assay. In conclusion, these findings provide a further biological basis for the potential therapeutic application of Q as an anticancer drug either alone or in combination with ADR in multidrug-resistant breast tumor cells.This work was partially supported by grants from MURST (60% and 40%) and CNR (Special Projects: A.C.R.O. 94.01098.PF 39); R. DeVincenzo and G. Ferrandina are recipients of fellowships from the Italian Association for Cancer Research (AIRC); M. Cianfriglia was partly supported by the AIDS research project (contract 720/P)     

Quercetin inhibits the growth of a multidrug-resistant estrogen-receptor-negative MCF-7 human breast-cancer cell line expressing type II estrogen-binding sites

Summary It has been demonstrated that the flavonoid quercetin (3,3,4,5,7-pentahydroxyflavone; Q) inhibits the growth of several cancer cell lines. There is evidence suggesting that the antiproliferative activity of this substance is mediated by the so-called type II estrogen-binding, site (type II EBS). We looked for the presence of type II EBS and the effect of Q on the proliferation of an Adriamycinresistant estrogen-receptor-negative human breast-cancer cell line (MCF-7 ADRr). By whole-cell assay using estradiol labelled with 6,7-tritium ([³H]-E2) as a tracer, we demonstrated that MCF-7 ADRr cells contain type II EBSs. Competition analysis revealed that diethylstilbestrol (DES) and Q competed with similar potency for [³H]-Es binding to type II EBSs. The antiestrogen tamoxifen (TAM) competed for type II EBSs, albeit to a lesser extent than either DES or Q. Growth experiments demonstrated that Q and DES exerted a dose-dependent inhibition of cell proliferation in the range of concentrations between 10 nM and 10 m, whereas TAM was less effective. Q could also inhibit colony formation in a clonogenic assay. Our results indicate that multidrug-resistant estrogen-receptor-negative MCF-7 cells express, type II EBSs and are sensitive to the inhibitory effect of Q. This substance could be the parent compound of a novel class of anticancer agents.     

Frequent loss of expression of the cyclin-dependent kinase inhibitor p27(Kip1) in estrogen-related Endometrial adenocarcinomas.

PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P 相似文献   

Effects of dexamethasone on the growth and epidermal growth factor receptor expression of the OVCA 433 ovarian cancer cells.

We studied the correlation between dexamethasone (Dex) induced growth effects and modulation of epidermal growth factor receptor (EGFR) expression in OVCA 433 ovarian cancer cells. These cells express specific high and low affinity 125I-EGF binding sites and are growth stimulated by EGF. Dex exhibits mitoinhibitory effects by recruiting OVCA 433 cells in the G0-G1 phase of the cycle, but increases the number of both the high and the low affinity EGFR in a dose dependent manner. The maximal EGFR expression increase occurs after 24 h of Dex treatment consistently with Northern blot studies. The mitogenic activity of EGF in OVCA 433 cells is not affected by the presence of Dex. Moreover Dex growth inhibition occurs in JA1 cells, an ovarian cancer cell line which expresses unfunctional EGFR and which is unresponsive to EGF. Our results indicate that the Dex induced growth effects occur independently of EGFR expression.