In particular, by checking the expression data of 1104 cancer and 113 normal samples from the TCGA project in ENCORI database, we found that these four genes showed strong expression in the breast cancer specimens as compared to their expression in normal breast tissue ( Including : MAD2L1, Fold change: 4.28, Adjusted P value: 1.4e−70; CCNA2, Fold change: 6.88, Adjusted P value: 3.2e−91; CCNB1, Fold change: 5.63, Adjusted P value: 1.8e−111; CDK1, Fold change: 8.54, Adjusted P value: 5.3e−121). This evidence concerns the gene CDK1 and breast cancer.