Validation of Altered MiRNAs in Ovarian Cancer Tumors”

Abstract

Epithelial ovarian cancer (EOC) is the second most important cause of cancer-relateddeaths among women worldwide. Due to the mild and common symptoms of EOC, thedisease can not be diagnosed at an early stage. Survival rate in ovarian cancer (OC)patients is limited to over 80%. When the disease spreads to the upper abdomen orother parts of the body (stage III and IV), only 20% of the patients survive for 5 years.Currently, diagnostic methods for EOC are pelvic examination, transvaginalultrasonography (TVS) and serum cancer antigen 125 (CA125), however EOC can notbe diagnosed at early stages. CA125 is the only serum biomarker routinely used forepithelial ovarian cancer and gives 99% certainty, but in postmenopausal womensensitivity to early disease is only 50-60%[1]. Therefore, finding a reliable biomarkerwith increased sensitivity to early stages of epithelial ovarian cancer remains animportant clinical problem.MicroRNAs (miRNAs) are a class of small non-coding RNAs 18-25 nucleotides inlength. MiRNAs are involved in various biological processes such as cell proliferation,development, differentiation, apoptosis. MiRNAs display abnormal expression patternsin different cancer forms. Some act as tumor suppressor genes or oncogenes.Expression of miRNAs is therefore important in the development of ovarian cancer [2].Studies have shown that there are differences in miRNA expressions between normalovarian epithelial and ovarian cancer epithelial.Hsa-mir-200c-3p, hsa-mir-4665-3p and hsa-mir-6737-3p expression levels areupregulated in ovarian cancer tissue to benign cyst samples by microarray results. Inthis study, 10 EOC tissue samples and 10 benign cyst samples (BCS) as control wereused and 3 miRNAs expression differences between these 2 groups are validated byReal-Time PCR method. This project aims to detect biomarkers with transcriptomicstudies in order to extend early 5 years survival time of women with cancer and earlydiagnosis of OC.