CD38 and cancer: Keywords in the red cluster included cancer, carcinoma, leukemia, acute myeloid leukemia, and bone-marrow; keywords in the green cluster included CD38, NAD, activation, oxidative stress, metabolism, and aging; keywords in the blue cluster included inflammation, risk-factor, biomarkers, immunosenescence and children; keywords in the yellow cluster included multiple myeloma, daratumumab, dexamethasone, monoclonal-antibody and therapy; keywords in the purple cluster included CD38 expression, prognosis, diagnosis, chronic lymphocytic leukemia and ZAP-70.