TP53 and anaplastic large cell lymphoma: Knockdown of EBP2 promoted the activation of the tumor suppressor p53, leading to G0/G1‐phase cell cycle arrest in Ba/F3 cells transformed by NPM‐ALK and ALCL patient‐derived Ki‐JK cells, but not ALCL patient‐derived SUDH‐L1 cells harboring p53 gene mutation.