In summary, local RT of the tumor increases the expression level of major histocompatibility complex (MHC) class I molecules and improves the ability of presenting antigens of antigen presenting cells (APCs), promotes the maturation of DCs, and initiates T cell activation, which in turn raises the level of CD8+ T cells (Figure 1) [3,15]. The gene discussed is HLA-C; the disease is neoplasm.