At least half of all tumors lose WT p53 function as a result of mutations [29], however a subset of tumors, such as cervical cancer, chronic lymphocytic leukaemia, acute lymphoblastic leukaemia, acute myeloblastic leukaemia, myeloma, neuroblastoma, melanoma, mantle cell lymphoma and sarcoma, retains WT p53, but its activity can be attenuated [30, 31]. This evidence concerns the gene TP53 and mantle cell lymphoma.