By analyzing 7,294 RNA-sequencing data of 16 tumor types from the Cancer Genome Atlas (TCGA), we observed that a predicted NCAPG overexpression rate was in 74.26% of samples for HCC, 68.96% for breast cancer (BRCA), 73.10% for lung adenocarcinoma (LUAD), 92.81% for lung squamous cell carcinoma (LUSC), 50.11% for colon adenocarcinoma (COAD), 40.93% for bladder urothelial carcinoma (BLCA), 66.2% for head, neck squamous cell carcinoma (HNSC), 65.06% for rectum adenocarcinoma (READ), and 41.18% for kidney renal papillary cell carcinoma(TCGA-KIRP) (Figure 3 and Supplementary Table 1). This evidence concerns the gene NCAPG and breast cancer.