CAR T Cells for Solid Tumors

Purpose of Review In this manuscript, we review the current state of chimeric antigen receptor (CAR) T cells, their successes and shortcomings in targeting solid tumors. These engineered receptors have evolved from an over reaching concept to a clinical product that has revolutionized cancer therapy. Recent Findings Unlike earlier generations of expanded tumor-infiltrating lymphocytes, CAR T cells are not limited to an MHC-restricted response. Armed with multiple costimulatory domains in one frame, CAR T cells carry unparalleled activation potential. CAR T cells for relapsed leukemia have had an enormous impact on the field of cancer immunology and have become a beacon of hope for some difficult to treat patients. Unfortunately, CAR T cells have to date not shown similar efficacy for solid tumors. Summary Here, we delve into specifics within solid tumor microenvironments that are responsible for dampening CAR T cell efficacy. Each of these elements constitutes a front where future opportunity lies. We encourage our readers to explore this field, which is in its infancy, and take steps to move it forward.