Consistent with results obtained from the TCGA-COAD cohort (Supplementary Figure 1A), six CRGs, including DPP7, GPRASP1, UNC5C, RAB3B, PCDH9, SLC18A2, were significantly downregulated, whereas CDR2L was upregulated in cancer tissues in comparison with paracancerous normal tissues (Figure 8). Here, PCDH9 is linked to cancer.