Since wild-type (WT) TP53 is retained in approximately 50% of NSCLCs, these data, together with previous observations made by us and others [8–11, 13], lead us to hypothesise that TP53WT NSCLC cells may have pro-tumorigenic or pro-survival properties that could be linked to the ability to enter p21-dependent quiescence. The gene discussed is TP53; the disease is non-small cell lung carcinoma.