To determine the prognostic significance of PD-L1, DARC, MSH2 and PMS2 expression in CRC from West African Black patients in Zaria, and also from animal model, we conducted IHC staining on human CRC FFPE samples pre and post-FOLFOX chemotherapy and in rat-bearing CRC that were treated with aspirin and aspirin plus FOLFOX in various combinations. This evidence concerns the gene PMS2 and colorectal carcinoma.