Additionally, there are also other immune checkpoints as the potential targets in immune checkpoint therapy, such as T cell immunoglobulin and mucin-domain containing-3 (TIM-3), indoleamine-pyrrole 2,3-dioxygenase-1 (IDO-1) and lymphocyte-activation gene 3 (LAG-3), and their related antibodies are being evaluated in preclinical tumor models and/or in the clinic. Here, IDO1 is linked to neoplasm.