MicroRNA-615-3p inhibits the tumor growth and metastasis of NSCLC via inhibiting IGF2.

MicroRNAs are essential regulators of cancer-associated gene at the post-transcriptional level and their expression isaltered in cancer tissues. Herein, we sought to identify the regulation of miR-615-3p in NSCLC progression and its mechanism. MiR-615-3p expression was significantly down-expression in NSCLC tissue than that in control normal tissue. Exogenous over-expression of miR-615-3p inhibited the growth and metastasis of NSCLC cells. In addition, the in vivo mouse xenograft model showed that over-expression of miR615-3p inhibited NSCLC growth and lung metastasis whereas down-expression of miR-615-3p caused an opposite outcome. Furthermore, we revealed that insulin-like growth factor 2 (IGF2) expressions was negatively correlated with miR-615-3p level in NSCLC specimens, and IGF2 knocked-down mimic the effect of miR-615-3p inhibition on NSCLC cell proliferation, migration and invasion phenotype. In addition, overexpression of IGF2 rescued the inhibition of miR-615-3p in NSCLC cells. Together, our results indicated that miR-615-3p played important roles in the regulation of NSCLC growth and metastasis by targeting IGF2.