MicroRNA-204 inhibits expression of B cell lymphoma-2 in non-small cell lung cancer and regulate cell biological behaviors

Abstract

Objective To investigate the expression of microRNA-204 (miR-204) in non-small cell lung cancer (NSCLC) tissues and the molecular mechanism of targeting B cell lymphoma-2 (bcl-2) in the regulation of cell proliferation, apoptosis and invasion in A549 cell line. Methods The expression of miR-204 was detected by real-time polymerase chain reaction in 45 NSCLC tissues. Cell counting kit-8 (CCK-8) assay, Transwell assay and cysteinyl aspartate-specific protease (Caspase)-3 assay were performed to access cell line proliferation, invasion and apoptosis ability of A549 cell line. The target gene of miR-204 was analyzed by bioinformatics combined with Dual-luciferase assay and function recovery assays. Results miR-204 expression level was down-regulated in NSCLC tissues compared with adjacent normal tissues (1.28±0.31 and 3.75±0.27, P=0.000) while the expression of bcl-2 was up-regulated in NSCLC tissues (3.46±0.40 and 0.78±0.48, P=0.000). Furthermore, the expression levels were correlated with the pathologic grades. MiR-204 can significantly decrease the proliferation and invasion ability, as well as increase apoptosis (P=0.000). Furthermore, a significant reduction of luciferase activity was detected in A549 cell after co-transfected with miR-204 and Dual-luciferase expression vector containing bcl-2 wide-type 3’-untranslated region when compared with muted-type region group (0.12±0.02 and 0.29±0.03, P=0.000). The biological behavior effect on A549 cell can be recovered through over express the level of bcl-2. Conclusion miR-204 is down-regulated in NSCLC, and regulate the proliferation, invasion and apoptosis of A549 cells via targeting bcl-2. Key words: MicroRNA-204; B cell lymphoma-2; Non-small cell lung cancer; Targeted-regulating