RESUMEN
Ovarian cancer is the seventh most common cancer in women and the most frequent cause of gynaecological malignancy-related mortality in women. Currently, no standardized reliable screening test exists. MicroRNA profiling has allowed the identification of signatures associated with diagnosis, prognosis and response to treatment of human tumours. The aim of this study was to determine if a microRNA signature could distinguish between malignant and benign ovarian disease. A training set of 5 serous ovarian carcinomas and 5 benign serous cystadenomas were selected for the initial experiments. The validation set included 20 serous ovarian carcinomas and 20 benign serous cystadenomas. The serum/plasma focus microRNA Exiqon panel was used for the training set. For the validation set a pick and mix Exiqon panel, which focuses on microRNAs of interest was used. A panel of 4 microRNAs (let-7i-5p, miR-122, miR-152-5p and miR-25-3p) was significantly down regulated in cancer patients. These microRNAs target WNT signalling, AKT/mTOR and TLR-4/MyD88, which have previously been found to play a role in ovarian carcinogenesis and chemoresistance. let-7i-5p, miR-122, miR-152-5p and miR-25-3p could act as diagnostic biomarkers in ovarian cancer.