IGFBP6 and gastric cancer: In order to verify the analysis results of TCGA at the mRNA level, we selected the differentially expressed IGFBPs in some tumor tissues and then performed qRT-PCR experiments to verify the expression of IGFBP1, IGFBP2, and IGFBP6 in 67 pairs of gastric cancer and adjacent tissues, as well as 44 pairs of colorectal cancer and adjacent tissues.