Down-Regulation of miRNA-34a, -143 and -212 in the Serum of Patients with Ovarian Cancer

Abstract

Introduction: Ovarian cancer is one of the most common gynecological malignancy, ranking sixth in frequency and seventh for mortality. Because of the late stage at diagnosis, 5-years survival of patients is remaining below 50% and almost 70% of women present at late stages of carcinogenesis. Expression profile of circulating miRNAs in serum have emerged as potential biomarkers for early detecting various types of diseases including cancer. Present project investigated the expression profile of miRNA-34a, miRNA-143 and miRNA-212 in the serum of 30 ovarian cancer patients and 30 healthy subjects. Materials and Methods: 5 cc of whole blood was collected from each participant and total RNA was extracted using acid guanidinium-phenol-chloroform methods. Expression of targeted miRNAs was evaluated after cDNA synthesis using Real-Time PCR methods. Results: Our results showed expression levels of miRNA-34a (P<0.0001), miRNA-143 (P=0.028) and miRNA-212 (P<0.0001) were significantly decreased in patients with ovarian cancer compare to controls. Data from Receiver Operating Characteristic (ROC) curve analysis has shown that expression profile of these miRNAs could act as potential biomarker for diagnosis of ovarian cancer patients. XRCC3 Thr241Met polymorphism has been associated with cancer susceptibility. Studies have shown a relationship between Thr241Met polymorphism and gastric cancer. The present study was aimed at examining the presence of XRCC3 Thr241Met polymorphism in patients diagnosed with gastric cancer in the city of Macapa. We analyzed 150 DNA samples, of which 100 comprised the control group and 50 were case patients. Our findings revealed that 76% of case samples had the Thr/Met genotype (OR (CI 95% 54.29 (18.84-156.38) p ≤ 0.0001) whereas in the control group, the same genotype represented 7%. Also, most gastric cancer patients with XRCC3 241 Met polymorphism were heterozygotes. Given the small sample size in this study, a larger number of patients will be analyzed.