Lung cancer cells with wild-type TP53 exist resistance to PLK1 inhibitor GSK461364A via activating a postmitotic tetraploid checkpoint and arrest in a pseudo-G1 state following PLK1 inhibition, while RNA silencing of TP53 increased the antitumor activity of GSK461364A (Degenhardt et al., 2010). The gene discussed is TP53; the disease is lung carcinoma.