TOX and plasma cell myeloma: TOX exhausts CD8+T lymphocytes in mouse models (infection (13–15) or tumor models) or human cancers, including melanoma, non-small cell lung carcinoma (16), colorectal cancer (17), liver cancer (18), bladder cancer, oral squamous cell carcinoma (19), acute myeloid leukemia (18, 20), multiple myeloma (21), and non-Hodgkin’s lymphoma (22) (Figure 1) (Table 1).