TP53 and cancer: Based on analysis of the 69 cancers that had been characterized for the presence or absence of p53 mutations, there was a significant association between high expression of the hypoxia response signature and mutation in p53—18 of 21 samples with high hypoxia response had a p53 mutation as compared to 12 of 48 low hypoxia response samples (p = 0.00025, Fisher's exact t-test).