Notably, EZH2 can affect the expressions of cell cycle inhibitors, e.g., EHZ2 silencing with RNA interference increased P53 and P21 levels to control CCNB1 expression for induction of cell cycle arrest in lung cancer cells, and EZH2 knock down brought about the increase of P21 and P27 expressions, resulting in CCND1 decrease in non-small cell lung cancer 39, 40. The gene discussed is CCND1; the disease is lung cancer.