The Discovery of Biomarkers in Cancer Immunotherapy

Abstract

Despite the advances made in cancer treatment, there are subsets of patients who do not respond to conventional chemotherapy treatment paradigms or who have disease-related relapse. Recently researchers have focused on the role that the immune system plays in cancer control. While previous conceptions of cancer were based on the proliferation of a single, clonal, disordered cell, an important hallmark of cancer is now accepted to be the evasion of cancer cells from immune destruction [1,2]. It is now appreciated that the interaction between cancer cells and immune cells within the microenvironment is the basis for cancer cell escape from immune surveillance. In an effort to address this issue, cancer immunotherapy has emerged as a treatment modality for various malignancies. Cancer immunotherapy is based on generating strategies to exploit the mechanisms that govern the interplay between cancer cells and immune cells within the microenvironment. This mini-review will provide background into the discovery of important biomarkers in current major cancer immunotherapy modalities including immune checkpoint blockade and chimeric antigen receptor (CAR) T cell therapy. Additionally, we will provide an overview of existing cutting-edge methodologies used in biomarker discovery, highlight the advantages of utilizing each method, and discuss current and future directions for biomarker discovery.