Certain protein such as PIGU even demonstrated negative immunoreactivity in some CRC tissue, which corresponded to previous studies using integrated proteogenomic analyses that conclude that CNA–mRNA correlations were significantly higher than CNA–protein correlations for genes in all three groups (CNA, mRNA and protein)(P< 1.0×10-10, Kolmogorov–Smirnov test) [8]. The gene discussed is PIGU; the disease is colorectal carcinoma.