MHC class I molecules present cancer antigens that are degraded in the cytosol by the immunoproteasome to CD8+ T cells. The degraded antigenic peptides are transported into the endoplasmic reticulum via TAP1/TAP2, where peptides are loaded onto the MHC class I complex, which is composed of a heavy chain and β2-microglobulin (β2m). Peptide loaded MHC class I complexes are transported to the cell surface through the Golgi and are presented to CD8+ T cells. NLRC5 is involved in the transactivation of MHC class I and class I related genes, which include HLA-A, HLA-B, HLA-C, β 2m, LMP2, LMP7 and TAP1. TAP- transporter associated with antigen processing; TCR- T-cell receptor; LMP2/LMP7- large multifunctional peptidase 2 and 7.