Immune checkpoint inhibition for the treatment of cancers: An update and critical review of ongoing clinical trials

Abstract

Advances in Cancer immunotherapy in the past few years include the development of medications that modulate immune checkpoint proteins. Cytotoxic T-lymphocyte antigen 4 (CTLA4), programmed cell death protein 1 (PD1), and programmed cell death ligand 1 (PD-L1) are three co-inhibitory receptors that are expressed in the tumor microenvironment. Immune checkpoint inhibitors (ICI) that target these biomarkers unleash the properties of effector T cells that are licensed to kill cancer cells. Immune checkpoint blockade has dramatically changed the treatment landscape of many cancers. In this Review, we describe the current data regarding clinical trials of ICIs in six important cancers, including hepatocellular carcinoma (HCC), renal cell cancer (RCC), hodgkin lymphoma (HL), non-hodgkin lymphoma (NHL), non-small cell lung cancer (NSCLC), and head and neck cancer carcinoma (HNSCC).