TP53 and neoplasm: Spontaneous MHC-I-restricted p53-specific cytotoxic T lymphocytes43,44 and MHC-II-restricted p53-specific proliferating T-helper cells45, 46, 47 are found in mice and patients, supporting that proteolysis of the intracellular p53 protein in tumors results in the presentation of p53-derived peptides restricted by MHCs at the tumor cell surface.