By inducing DNA damage through treating pancreatic cancer CFPAC-1 cells with gemcitabine, an anti-cancer drug that disrupts DNA synthesis by introducing a mismatching 2′,2′-difluoro-2′-deoxycytidine triphosphate (dFdCTP) nucleoside into the DNA sequence, CD147 rescued the cancer cells from undergoing apoptosis by inducing phosphorylation of p53 through the ATM/ATR/p53 pathway; phosphorylated p53 is stable from Mdm2-mediated ubiquityl degradation therefore, p53 translocates to the nuclear and activates DNA repair (86). This evidence concerns the gene ATR and cancer.