HLA-C and gastric cancer: Therefore, it is biologically plausible that functional interleukin gene polymorphisms may be associated with the risk of developing gastric cancer.IL-10 is a multifunctional cytokine with immunosuppressive and antiangiogenic functions, and it reduces the expression of MHC class in antigen presenting cells (APCs)17 and tumor cells by downregulating the expression of MHC class or inhibit antigen presentation, thereby contributing to an immunosuppressive environment [29–31].