TP53 and squamous cell carcinoma: To investigate this, we analyzed four cancer cell lines derived from a pancreatic ductal adenocarcinoma (PANC-1), epidermoid carcinoma (A431), colorectal adenocarcinoma (HT-29), and non-small cell lung adenocarcinoma (NCI-H1975), each harboring the TP53-R273H mutation together with numerous unique co-occurring mutations (Additional file 1: Table S1).