TP53 and breast cancer: Some scholars have studied the antitumor effect of the antibacterial drug berberine and found that ribosomal protein (RP) L5 disappeared from the nucleolus and the accumulation of p53 protein in the nucleus in breast cancer MCF7 cells treated with 10 mM or 100 mM berberine, and RPL5 downregulation of berberine inhibited berberine-driven induction of p53 and p21 and cell death in MCF7 cells [16].