MAPK3 and small cell lung carcinoma: Importantly, Chen et al revealed miR-134 regulated SCLC cell growth and apoptosis by targeting WWOX gene and suppressing the ERK1/2 signaling pathway [36], and Li et al discovered miR-134 inhibits epithelial to mesenchymal transition by targeting FOXM1 in non-small cell lung cancer cells [38], but among the miRNAs predicted to target genes, we found that cyclin D1 acts as a critical effector of miR-134.