A phase II trial showed that 40 days after infusion of ex vivo amplified TILs that contained specific CD8+ T cells targeting neoepitope derived from the KRAS mutation G12D, a patient with metastatic colorectal cancer encountered regression of all the metastatic lung lesions, suggesting an important role of neoepitope-reactive CD8+ T cells in cancer therapy (51). The gene discussed is KRAS; the disease is cancer.