A study performed on the various stages of papaya ripening time found that ribosome-inactivating proteins (RIPs) isolated from Carica papaya leaves have cytotoxic activity in breast cancer cell line with the IC50 of 2.8 mg/mL, where the expression level of Bcl-2 protein decreased by the ratio 63%, and p53 increased by 59.4% [24]. The gene discussed is TP53; the disease is breast carcinoma.