The qRT-PCR results indicated that, among the 63 colorectal cancer patient tissues, 42 patients exhibited lower mRNA expression of PCDHGA9 in CRC tissue compared with paracancerous tissue (Fig. 1a), and overall survival and disease-free survival analysis demonstrated that colorectal cancer patients with reduced PCDHGA9 expression had poorer survival rates (Fig. 1b, c). This evidence concerns the gene PCDHGA9 and colorectal carcinoma.