The future of immune checkpoint blockade immunotherapy: towards personalized therapy or towards combination therapy

One of the major breakthroughs in cancer immunotherapy in the past decades was the discovery of immune checkpoint molecules, notably cytotoxic T-lymphocyte associated protein 4 (CTLA-4) (1) and the programmed cell death-1 (PD-1, also known as CD279) T-cell receptor (2) and its ligands (programmed death-ligand 1 (PD-L1, also known as B7-H1 or CD274) (3) and PD-L2 (also known as B7-DC or CD273) (4).