In the immunogenic MC38 tumor model, the pool size of the progenitor CD8+ TILs was small (<8%), so the long-term antitumor immunity was likely limited by the maintenance of the progenitor subset of exhausted CD8+ TILs, which can be significantly improved by perturbing T cell-intrinsic LSD1. The gene discussed is KDM1A; the disease is neoplasm.