Expression and promotor methylation of p73 gene in ovarian epithelial tumors / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate the expression and promoter methylation status of p73 gene in ovarian epithelial tumors and their clinicopathological correlations.</p><p><b>METHODS</b>Tissue microarrays (TMA) consisting of 68 ovarian cancers, 37 ovarian borderline tumors and 21 ovarian benign tumors were constructed. p73 expression was detected by immunohistochemistry (EnVision method). Fresh-frozen tissue samples from 13 cases of ovarian carcinomas and 5 cases of borderline tumors were evaluated for the presence of p73 promoter methylation using bisulfite sequencing.</p><p><b>RESULTS</b>Overall, 92.6% (63/68) ovarian carcinomas expressed p73, with a mean value of 32% (percentage of p73 positive cells in the tumor). The mean value of p73 expression rate (40%) in serous carcinoma (26/26) was higher than those of other cancer types (P = 0.006). The mean value of p73 expression rate (40%) in type II ovarian carcinoma was significantly higher than that in type I ovarian carcinoma (24%, P = 0.010). The expression of p73 was not associated with FIGO stage and histological grade (both P > 0.05). The mean values of p73 expression in ovarian borderline tumor (30/37) and benign tumor (12/21) were 16% and 15%, respectively. Of the two groups, the mean value of p73 expression rate in serous type was higher than that in mucous type (P = 0.003, P = 0.026). Ovarian carcinomas had a higher level of p73 expression than borderline tumors and benign tumors (both P < 0.05), while that between ovarian borderline tumors and benign tumors had no statistical difference (P > 0.05). Among serous tumors (49/53), the mean value of p73 expression in the carcinoma group (26/26) was significantly higher than those in the borderline tumor group (12/14) and benign tumor group (11/13; P = 0.024 and P = 0.002, respectively), while that between borderline tumor group and benign tumor group had no statistical difference (P = 0.428). Among mucous tumors (15/27), the mean value of p73 expression in carcinoma group (6/7) was higher than that in benign tumor group (1/8; P = 0.032). No statistical difference of p73 expression was seen between the carcinoma group and ovarian borderline tumor group (8/12) and between the borderline tumor group and benign tumor group (P = 0.234, P = 0.201, respectively). p73 promotor methylation was found in 8 of 13 cases of carcinomas but at different methylation levels with a mean value of 8.0%. Two of 5 ovarian borderline tumors showed detectable p73 promotor methylation with a mean value of 9.0%. Compared with the borderline tumors, ovarian carcinomas showed a similar p73 methylation level (P > 0.05). The p73 methylation level in ovarian carcinomas was not associated with histological type, pathogenetic type, histological grade and FIGO stage (all P > 0.05).</p><p><b>CONCLUSIONS</b>Most of ovarian epithelial tumors express p73 protein with mean values higher in ovarian carcinomas than those in the borderline and benign tumors. Ovarian serous carcinomas have the highest expression level of p73. A simple linear correlation does not exist between the promoter methylation and protein expression of p73.</p>

Expression and significance of microRNAs in the p53 pathway in ovarian cancer cells and serous ovarian cancer tissues / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The aim of this study was to investigate whether miR-449a, miR-449b and miR-192 family microRNAs play the same roles in p53 pathway as miR-34 family in ovarian cancer.</p><p><b>METHODS</b>Wild-type p53 ovarian carcinoma cell line A2780 cells were treated with genotoxic agent adriamycin. The reactivation of p53 was detected by Western blot. The expression of miR-449a/b, miR-34a, miR-34b, miR-34c, miR-192 and miR-194 were detected by real-time quantitative PCR. Mutant p53 ovarian cancer cell line SKOV3.ipl cells were transfected with pre-microRNAs and the cell-cycle changes were detected. The expression level of miR-449a/b, miR-34a, miR-34b, miR-34c, miR-192 and miR-194 in serous ovarian carcinomas of varying grade and stage were compared with real-time PCR.</p><p><b>RESULTS</b>The expressions of miR-449a/b, miR-34b and miR-34c were 19-fold to 21-fold elevated after p53 activation by genotoxic agent. Ectopic expression of miR-449b, as well as miR-34c, resulted in cell-cycle arrest in SKOV3.ipl cells. The expression of miR-449a/b was parallel with that of miR-34b, miR-34c, and were significantly lower in late stage and high-grade serous carcinomas than in the normal fallopian tube, early stage and low-grade serous carcinomas. The expression of miR-192, miR-194 and miR-34a did not show evident features in serous ovarian carcinomas and were much lower than miR-449a/b, miR-34b and miR-34c in normal fallopian tube.</p><p><b>CONCLUSIONS</b>As tumor-suppressor microRNAs, miR-449a/b, miR-34b and miR-34c cooperate and play important roles in p53 pathway. Their inactivation may contribute to the carcinogenesis and progression of serous ovarian carcinomas.</p>

Effect of human epididymis protein 4 gene silencing on the malignant phenotype in ovarian cancer / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human epididymis secretory protein 4 (HE4) has been proved to be a promising novel biomarker for the detection of epithelial ovarian carcinomas. Compared with CA125, HE4 assay demonstrated an improved ability to discriminate between pelvic mass with malignant and benign disease. Though it is well known that HE4 is overexpressed in ovarian cancer, however, the role of HE4 in the carcinogenesis and progression of ovarian cancer remains unkown.</p><p><b>METHODS</b>In this study, we explored the role of HE4 in the carcinogenesis and progression of ovarian cancer. We screened nine ovarian cancer cell lines for HE4 expression, and using RNA interference (RNAi), we silenced HE4 gene expression in CaoV3 and SKOV3.ip1 ovarian cancer cell lines. We assessed the effect of HE4 gene silencing on the transformed phenotype by examining the cell cycle, apoptosis, proliferation and transwell migration/invasion in vitro.</p><p><b>RESULTS</b>HE4 gene silencing induces G0/G1 arrest and blocks the progression from the G1 to S phase in CaoV3 and SKOV3.ip1 cells. HE4 knockdown also inhibited cell proliferation, migration and invasion in SKOV3.ip1 cells in vitro.</p><p><b>CONCLUSION</b>HE4 may be involved in the regulation of the cell cycle and promote ovarian cancer migration and invasion.</p>

Screening for genes associated with ovarian cancer prognosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human epithelial ovarian cancer cell line SKOV3.ip1 is more invasive and metastatic compared with its parental line SKOV3. A total of 17 000 human genome complementary DNA microarrays were used to compare the gene expression patterns of the two cell lines. Based on this, the gene expression profiles of 22 patients with ovarian cancer were analyzed by cDNA microarray, and screened the 2-fold differentially expressed genes compared with the normal ones. We screened genes relevant to clinical prognosis of serous ovarian cancer by determining the expression profiles of ovarian cancer genes to investigate cell receptor and immunity-associated genes, and as groundwork, identify ovarian cancer-associated antigens at the gene level.</p><p><b>METHODS</b>Total RNA was extracted from 22 patients with ovarian cancer and DNA microarrays were prepared. After scanning, hybridization signals were collected and the genes that were differentially expressed twice as compared with the normal ones were screened.</p><p><b>RESULTS</b>We screened 236 genes relevant to the prognosis of ovarian cancer from the 17 000 human genome cDNA microarrays. According to gene classification, 48 of the 236 genes were cell receptor or immunity-associated genes, including 2 genes related to the International Federation of Gynecology and Obstetrics (FIGO) stage, 4 genes to histological grade, 18 genes to lymph node metastasis, 11 genes to residual disease, and 13 genes to the reactivity to chemotherapy. Several functionally important genes including fibronectin 1, pericentriolar material 1, beta-2-microglobulin, PPAR binding protein were identified through review of the literature.</p><p><b>CONCLUSIONS</b>The cDNA microarray of ovarian cancer genes developed in this study was effective and high throughput in screening the ovarian cancer-associated genes differentially expressed. Through the studies of the cell receptor and immunity-associated genes we expect to identify the molecular biology index of ovarian cancer-associated antigens.</p>

Construction and utilization of the prognostic model of serous ovarian adenocarcinoma / 中华妇产科杂志

Objective To analyze the related factors with prognosis in patients with serous ovarian adenocarcinoma and to set up a prognostic model of serous ovarian adenocarcinoma.Methods The clinical, pathological and follow-up data of 104 cases with serous ovarian adenocarcinoma were retrospectively analyzed.Kaplan-meier univariate analysis was used to screen the prognostic factors;COX univariate and multivariate analyses were used to determine the risk coefficient of each factors and different layers in each factor.Pearson rank correlation was used to reject the influence of different factors with each other.And the prognostic model of serous ovarian adenocarcinoma was set up based on the result of the above study,which could be used to deduce the survival probability of patients with serous ovarian adenocarcinoma.Results International Federation of Gynecology and Obstetrics(FIGO)stage(P=0.0029),histological grade(P= 0.0054),residual disease(P=0.0000),metastasis of lymph nodes(P=0.0000)and chemotherapy(P= 0.0000)were the related factors of prognosis in patients with serous ovarian adenocareinoma,of which FIGO stage was the most important one,followed sequentially by histological grade,metastasis of lymph node, residual disease and chemotherapy(the independent risk coefficient of each factor was 1.3392,0.9206, 0.7071,0.6004,0.4985 in sequence).We set up a prognosis model according to the prognostic index of each factors.The effect of chemotherapy and residual disease on prognosis could be quantified by this model, and the higher the score,the lower the survival probability of patients.Condusions FIGO stage, histological grade,residual disease,metastasis of lymph nodes and chemotherapy are important prognostic factors of serous ovarian adenoearcinoma.This model can be used to estimate the prognosis of patients with serous ovarian adenoearcinoma,and the effect of both chemotherapy and residual disease on the prognosis could be quantified by the model.