TP53 and B-cell chronic lymphocytic leukemia: Herein, we used a CLL mouse model (Eμ-TCL1) harboring one of the most common TP53 hot-spot mutations observed in CLL (p53R172H, corresponding to p53R175H in humans) to evaluate its impact on disease progression, survival, response to therapy and loss of the remaining wild-type Trp53 allele following ibrutinib treatment.