Harnessing immune checkpoints for cancer therapy.

Immunomodulatory antibodies that directly trigger and reawaken suppressed T-cell effector function are termed 'checkpoint inhibitors'. CTLA-4 and PD-1/PD-L1 molecules are the most studied inhibitory immune check points against cancer and because of this therapeutic property have entered the clinic for treating a variety of tumor types. The results so far demonstrate a positive impact on cancer remission. Preclinical studies have demonstrated that targeting a number of other T-cell surface molecules including both positive and negative immune regulators, also possesses strong antitumor activity. Some of these molecules have already entered clinical trials. In this report, we briefly highlight the status of these immune checkpoint inhibitors and discuss their side effects and future directions for their use.