The cell lines used are HepG2 (p53 wild-type hepatoma cells), A549 (p53 wild-type lung carcinoma cells), U2-OS (p53 wild-type osteogenic sarcoma cells), MDA-MB231 (p53 mutant breast adenocarcinoma cells), HT-29 (p53 mutant colon adenocarcinoma cells), Hep3B (p53 null hepatoma cells), and PC-3 (p53 null prostate adenocarcinoma cells) cells. The gene discussed is TP53; the disease is colon adenocarcinoma.