Recent updates on cancer immunotherapy

Abstract

Traditional cancer therapies include surgery, radiation, and chemotherapy, all of which are typically non-specific approaches. Cancer immunotherapy is a type of cancer treatment that helps the immune system fight cancer. Cancer immunotherapy represents a standing example of precision medicine: immune checkpoint inhibitors precisely target the checkpoints; tumor infiltrating lymphocytes, TCR T cells, and CAR T cells precisely kill cancer cells through tumor antigen recognition; and cancer vaccines are made from patient-derived dendritic cells, tumor cell DNA, or RNA, or oncolytic viruses, thus offering a type of personalized medicine. This review will highlight up-to-date advancement in most, if not all, of the immunotherapy strategies.

Keywords: cancer; immune evasion; immunotherapy.

Figure 1.

Diagram of mechanisms of tumor immune evasion. Tumor cells evade immune responses through a variety of mechanisms: (i) downregulation of antigen processing and presentation machinery and thus antigen presentation (see ↓), (ii) upregulation of PD-L1 on tumor cells and PD-1 on effector T cells (see ↑) and facilitation of binding of PD-L1 and B7-1/2 to PD-1 and CTLA-4, respectively, (iii) secretion of immune suppressive modulators (TGF-β, IL-8, IL-10, IL-18, CSF1, VEGF, gangliosides, ROS, Kynurenines, K⁺) and metabolites (adenosine, PGE, lactate) into TME, (iv) deprivation of immune activating metabolites (glucose, arginine, glutamine, tryptophan) from TME, (v) recruitment and/or activation of Treg, MDSC and TAM, and (vi) inhibition of effector T cell infiltration.