As shown in Table 1, four (CCNA2, CENPN, DEPDC1, and TTK; DOE-A) and three genes (ABAT, LRIG1, and PGR; DUE-A) were identified as differentially over- and under-expressed genes, respectively, as described in “Methods” and they were selected as novel biomarker candidate genes for breast cancer and were subjected to the subsequent analyses. Here, PGR is linked to breast cancer.