TP53 and squamous cell carcinoma: Notably, in pancreatic adenocarcinoma (PAAD), esophageal adenocarcinoma (ESAD), squamous cell carcinoma (ESCC), head and neck squamous cell carcinoma (HNSC), colorectal adenocarcinoma (COAD) and skin cutaneous melanoma (SKCM), the frequency of TP53 exon-6 truncating mutations was higher than 6% (Supplementary file 1).