In comparison with normal tissues, three biomarkers, CCDC181, GCM2 and ITPRIPL1, were found to be simultaneously hypermethylated only in breast tumors in TCGA and Taiwanese patients, but not in lung cancer, uterine cancer, ovarian cancer, gastric cancer, esophagus cancer, pancreatic cancer, liver cancer or colorectal cancer (Figure 2 and Table S5). This evidence concerns the gene CCDC181 and lung cancer.