CDK4 and non-small cell lung carcinoma: 3) The levels of vital cell cycle-related molecules (CDK4, CDK6, cyclin A2 and cyclin D1) were remarkably altered in the MCRS1 knockdown NSCLC cells, consistent with previous observations that MCRS1 modulated cellular proliferation through affecting cell cycle-related molecules [9, 16, 21, 22].