In tumor cells, the down-regulation of MHC class I molecules helps them to avoid detection by CD8+ T cells, meanwhile changes in the processing pathway of classical and non-classical human leukocyte antigen (HLA) and antigen presentation provide multiple pathways for renal cell carcinoma cells to weaken the immune responses of the body, resulting in more tumor growth and host immune surveillance evasion (6). The gene discussed is CD8A; the disease is renal cell carcinoma.