In the case of PDAC that lack tumor-infiltrating CD8+ T cells (i.e., immune-exclusion PDAC [36]), administration of immune checkpoint blockers might be combined with conventional chemotherapy (i.e., gemcitabine plus nab-paclitaxel) aimed at boosting the immune response via an increased CD8+ effector T-cell/FOXP3+ Treg ratio, associated with a significantly higher density of CD8+ T-cells inside (on-treatment) tumor samples, as observed among PDAC responders in phase II clinical trials (NCT02077881) [122]. The gene discussed is CD8A; the disease is neoplasm.