CDKN2A and cancer: CDK4/6i‐treated cells assumed a flattened and enlarged morphology (Fig EV1J), activated the senescence‐associated‐β‐galactosidase (SA‐β‐gal) (Fig EV1K), and maintained high level of the endogenous CDK4/6i p16 (Fig EV1L), all features that can also be observed in cells treated with other anti‐cancer and senescence‐inducing agents such as the genotoxic drug doxorubicin (Demaria et al, 2017).