TP53 and breast carcinoma: Upon miR-644a overexpression, breast cancer cell lines with p53 mutation (p53-mut) only underwent apoptosis evidenced by increased cleaved caspase-3 (Figure 1D and 1E) by inducing G2/M arrest characterized by increased phosphorylation of G2/M-arrest markers Cdc2 and Cdc25C (Figure 1F and 1H).