TP53 and metastatic neoplasm: Studies using murine models have observed that mutant p53 knock-in mice develop more aggressive and metastatic tumors in comparison to p53 null mice, and that the different p53 mutants are associated with distinct tumor patterns (Lang et al., 2004; Olive et al., 2004; Lozano, 2007; Song et al., 2007; Oren and Rotter, 2010).