We observed that tumor samples from T-cell acute lymphoblastic leukemia (T-ALL) patients and some T-ALL cell lines had high TOX and TOX2 expression together with a low level of TIM3 expression, contradicting previous reports that TOX and TOX2 upregulate TIM3 expression in tumor-specific T cells. The gene discussed is HAVCR2; the disease is T-cell acute lymphoblastic leukemia.