The Profiling of Apoptosis-Associated MicroRNA Expressions of the Lung Adenocarcinoma.

Abstract

The most common histopathological subtype of lung cancer is adenocarcinoma. MicroRNAs are a class of non-coding RNAs that play roles in the regulation of gene expression. MicroRNAs affecting apoptosis may have different roles in lung adenocarcinoma development, progression, and differentiation. The objective of this study is to profile all known microRNAs linked to apoptosis in normal and lung cancer tissue using real-time polymerase chain reaction. Tissues with adenocarcinoma and healthy tissues were taken from the same lung. The degree of differentiation of all tumors was determined. Expressions of 84 apoptosis-associated microRNAs in both tissues were analyzed by real-time polymerase chain reaction array. Eleven patients and 22 samples were included in the study. In the comparison of expression levels of apoptosis-associated microRNAs in normal and adenocarcinoma tissue, miR-134, miR-183-5p, miR-192-5p, miR-193b-3, miR-194-5p, miR-200c-3, miR212-3p, miR-25-3p, miR-449a, and miR-9-5p showed significant difference in downregulation. Receiver operating characteristic curve analysis of 10 identified microRNAs was performed, and cut-off values, sensitivity, and specificity were determined. No significant difference was found between microRNA expression levels in adenocarcinoma tissues classified as moderate-well to poorly differentiated. Differently, downregulated expressed apoptosis-associated microRNAs were detected in lung adenocarcinoma tissues. MicroRNAs can be used as biomarkers in the diagnosis in lung adenocarcinoma. The expression of microRNAs linked to apoptosis should be investigated in different lung cancer histological subtypes in order to identify potential biomarkers.