RRM2 and breast cancer: On the other hand, Breast cancer type 1 susceptibility protein (BRCA1), BAX, Poly [ADP‐ribose] polymerase 1 (PARP1), Epithelial cell adhesion molecule (EPCAM), Breast cancer type 2 susceptibility protein (BRCA2), CDC25A, Cyclin B1 (CCNB1), Cyclin‐dependent kinase 1 (CDK1), Ribonucleoside‐diphosphate reductase subunit M2 (RRM2), and Matrix metalloproteinase 1 (MMP1) were significantly upregulated in breast cancer tissue compared to normal tissue.