BackgroundMicroRNA (miRNA) expression is known to be deregulated in ovarian carcinomas. However, limited data is available about the miRNA expression pattern for the benign or borderline ovarian tumors as well as differential miRNA expression pattern associated with histological types, grades or clinical stages in ovarian carcinomas. We defined patterns of microRNA expression in tissues from normal, benign, borderline, and malignant ovarian tumors and explored the relationship between frequently deregulated miRNAs and clinicopathologic findings, response to therapy, survival, and association with Her-2/neu status in ovarian carcinomas.MethodsWe measured the expression of nine miRNAs (miR-181d, miR-30a-3p, miR-30c, miR-30d, miR-30e-3p, miR-368, miR-370, miR-493-5p, miR-532-5p) in 171 formalin-fixed, paraffin-embedded ovarian tissue blocks as well as six normal human ovarian surface epithelial (HOSE) cell lines using Taqman-based real-time PCR assays. Her-2/neu overexpression was assessed in ovarian carcinomas (n = 109 cases) by immunohistochemistry analysis.ResultsExpression of four miRNAs (miR-30c, miR-30d, miR-30e-3p, miR-370) was significantly different between carcinomas and benign ovarian tissues as well as between carcinoma and borderline tissues. An additional three miRNAs (miR-181d, miR-30a-3p, miR-532-5p) were significantly different between borderline and carcinoma tissues. Expression of miR-532-5p was significantly lower in borderline than in benign tissues. Among ovarian carcinomas, expression of four miRNAs (miR-30a-3p, miR-30c, miR-30d, miR-30e-3p) was lowest in mucinous and highest in clear cell samples. Expression of miR-30a-3p was higher in well-differentiated compared to poorly differentiated tumors (P = 0.02), and expression of miR-370 was higher in stage I/II compared to stage III/IV samples (P = 0.03). In multivariate analyses, higher expression of miR-181d, miR-30c, miR-30d, and miR-30e-3p was associated with significantly better disease-free or overall survival. Finally, lower expression of miR-30c, miR-30d, miR-30e-3p and miR-532-5p was significantly associated with overexpression of Her-2/neu.ConclusionsAberrant expression of miRNAs is common in ovarian tumor suggesting involvement of miRNA in ovarian tumorigenesis. They are associated with histology, clinical stage, survival and oncogene expression in ovarian carcinoma.

BackgroundMicroRNA expression is severely disrupted in carcinogenesis, however limited evidence is available validating results from cell-line models in human clinical cancer specimens. MicroRNA-21 (mir-21) and microRNA-143 (mir-143) have previously been identified as significantly deregulated in a range of cancers including cervical cancer. Our goal was to investigate the expression patterns of several well-studied microRNA species in cervical samples and compare the results to cell line samples.Methodology/Principal FindingsWe measured the expression of mir-21 and mir-143 in 142 formalin-fixed, paraffin embedded (FFPE) cervical biopsy tissue blocks, collected from Dantec Oncology Clinic, Dakar, Senegal. MicroRNA expression analysis was performed using Taqman-based real-time PCR assays. Protein immunohistochemical staining was also performed to investigate target protein expression on 72 samples. We found that mir-21 expression increased with worsening clinical diagnosis but that mir-143 was not correlated with histology. These observations were in stark contrast to previous reports involving cervical cancer cell lines in which mir-143 was consistently down-regulated but mir-21 largely unaffected. We also identified, for the first time, that cytoplasmic expression of Programmed Cell Death Protein 4 PDCD4; a known target of mir-21) was significantly lower in women with invasive cervical carcinoma (ICC) in comparison to those with cervical intraepithelial neoplasia (2–3) or carcinoma in situ (CIN2-3/CIS), although there was no significant correlation between mir-21 and PDCD4 expression, despite previous studies identifying PDCD4 transcript as a known mir-21 target.ConclusionsWhilst microRNA biomarkers have a number of promising features, more studies on expression levels in histologically defined clinical specimens are required to investigate clinical relevance of discovery-based studies. Mir-21 may be of some utility in predictive screening, given that we observed a significant correlation between mir-21 expression level and worsening histological diagnosis of cervical cancer.

GATA3 plays a role in cell proliferation and differentiation in many tissues, including breast, and it has been suggested that GATA3 expression correlates with ER expression. However, little is known on GATA3 expression in various subtypes of breast carcinoma, its utilization in cytology, and on how GATA3 performs in comparison with GCDFP-15 and mammaglobin. Eighty-four histology cases of breast carcinoma of various subtypes, including 28 triple-negative breast carcinomas, along with 20 cytology cases of metastatic breast carcinoma and 12 cytology cases of ER-positive metastatic gynecologic malignancies, were stained for GATA3, GCDFP-15, and mammaglobin. In non-triple-negative breast carcinomas (n=56), GATA3 showed 100% sensitivity, higher than GCDFP-15 (42.8%; P<0.0001) and mammaglobin (58.9%; P<0.0001), whereas staining patterns were similar for all the histologic subtypes examined. Staining scores were determined by multiplying the percentage of cancer cells staining with an intensity score of 1+, 2+, or 3+ (range, 0 to 300). In non-triple-negative carcinomas, GATA3 showed a mean score of 273.7, higher than GCDFP-15 (107.5; P<0.0001) and mammaglobin (147.7; P<0.0001). In triple-negative breast carcinomas (n=28), GATA3 showed a sensitivity of 60.7%, greater than GCDFP-15 (17.9%; P=0.0022) and mammaglobin (7.1%; P<0.0001). These results were consistent irrespective of the subtype examined. In breast carcinoma cytology cases, 100% stained with GATA3, higher than GCDFP-15 (20%; P<0.0001) and mammaglobin (45%; P<0.0001). None of the metastatic endometrial or ovarian carcinomas were positive for GATA3. Although GATA3 expression correlates with ER expression in breast, no correlation is observed in gynecologic malignancies. Thus, in working up ER-positive metastatic malignancies GATA3 demonstrates specificity for breast.

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