The Expression of MicroRNA-146a in Adenomatous Polyps and Colorectal Cancer

Background and Colorectal cancer (CRC) is one of the most common types of cancer. Its incidence has increased in Iran during the last 25 years. Micro-RNAs are used as new approach in cancer researches. The roles of miR-146a have been detected in different tumors. This study aimed at investigating the expression of microRNA146 in tumor tissue of colorectal adenocarcinoma in various stages of colorectal cancer using Real Time PCR. In this experimental study, 70 paraffin blocks from 50 patients and 20 healthy individuals (during 2012-2014) were studied. The total amount of RNA in tissues was deparaffinized using RNA extraction kit and the RNA concentration was measured by NanoDrop®. miR-146a from total RNA was extracted by qRT_PCR. The expression of miR-146a gene was studied by light cycler and 2-ΔΔCT was applied to measure the gene expression. Data was analyzed using ANOVA and paired t-test. Significant differences were seen in expression of mir-146a in adenomatous polyps and colorectal cancer tumors (stage I-IV) compared with those of the healthy tissues (P<0.05) which were associated with increase in mir-146a expression. Increase in the expression of mir-146a is directly associated with development of cancer in pre-cancer (adenocarcinoma) and advanced cancer.