MiR-30a suppresses non-small cell lung cancer progression through AKT signaling pathway by targeting IGF1R.

MicroRNAs play critical roles in the development and progression of human cancers. Although miR—30a has been suggested to function as a tumor repressor in several tumors, its role in non—small cell lung cancer (NSCLC) has not been investigated in detail. This study investigated the expression and role of miR—30a in human NSCLC. The expression of miR—30a is significantly decreased in clinical NSCLC tissues and cell lines. Overexpression of miR—30a inhibited NSCLC cell proliferation, G1/S and S/G2 transition in vitro, whereas suppression of miR—30a facilitated NSCLC cell proliferation, G1/S and S/G2 transition. Using a luciferase reporter assay, insulin—like growth factor 1 receptor (IGF1R) was determined to be a direct target of miR—30a. Furthermore, silencing IGF1R resulted in the same biologic effects of miR—30a overexpression in NSCLC cells, which included suppressed NSCLC cell proliferation and trigering cell cycle arrest through PI3K/AKT signaling pathway by inhibiting cell cycle regulators (CDK2, CDK4, Cyclin A2 , Cyclin D1). These results demonstrate that miR—30a influences NSCLC progression through PI3K/AKT signaling pathway by targeting IGF1R in A549 cells, which suggest miR—30a as a novel strategy for NSCLC diagnosis and treatment.