CD27 and colorectal carcinoma: Moreover, 13 genes were upregulated in PBMCs of all CRC patients’ groups; CCR3, CD2, CD27, CD3G, CD8B, FAS, IL10, IL18R, IL5, LAG3, MAP3K7, TLR1 and TLR6. The serum levels of the four IgG subclasses were however statistically insignificant in CRC patients compared to healthy controls.