The methylation status of 13 CpG promoter sites (chr7: 23287345–23,287,426) in GPNMB was measured by pyrosequencing using primers designed by EpigenDx primers were first tested on three human colorectal cancer cell lines (HCT116, HT29, and SW480) and one male normal blood DNA by pyrosequencing. This evidence concerns the gene GPNMB and colorectal cancer.