TP53 and cancer: A leaf extract (PBL) from Piper betel, a medicinal plant from the Piperaceae used in chemoprevention for several cancers [162,163], has been shown to induce apoptosis and cell cycle arrest in hepatocellular carcinoma Hep3B (p53 null) cells by increasing the expression of p73, phosphorylated-p73, p21, Bax, and caspase-3 [164].