TP53 and neoplasm: With the control of wild type cells, we treated engineered mouse tumor cell lines p53−/−+Ras and p53−/−+S+Ras with Pu-erh tea solution of a serial of concentrations: 0.1 mg/mL, 0.2 mg/mL, 0.3 mg/mL, 0.4 mg/mL and 0.5 mg/mL.