Interestingly, PDAC tumors bearing DSBR and/or MMR gene signatures also exhibit a higher frequency of somatic mutations and tumor-associated neoantigens [128], which leads to increased immunogenicity associated with an enhanced local antitumor immunity, as reflected by increased activation of CD8+ T lymphocytes, a high T effector/Treg cell ratio, and overexpression of regulatory molecules such as CTLA-4, PD-1 and IDO-1 [36]. The gene discussed is CD8A; the disease is neoplasm.