CAR T cell therapy: Current limitations and advancements in treating solid tumors

Abstract

An emerging technology that tackles cancer via immunotherapy known as CAR T cell therapy has been gaining great popularity after its success in treating leukemia and other forms of blood cancer. However, major advancement to treat other forms of cancer have not been attained as this treatment is still facing major obstacles in addressing solid tumors due to tumor heterogeneity, hostile microenvironment, on-target/off-tumor toxicities, antigen specificity, and difficult infiltration. Moreover, this treatment has also been associated with threatening side-effects like mass dieoff of antibody producing B cells, CRS, and ICANS. Thus, because of simplified manipulation yet lack of knowledge of the physiology behind the mechanisms, significant progress has not yet been achieved-though on its way. Scientists explored multiple ways of addressing these major challenges by researching on feasible techniques, antigens, and mechanisms that can increase T cell reproduction, decrease toxicity, overcome and infiltrate into the hostile microenvironment, and target multiple antigens via TAA. It is a technology that is not yet fully developed; therefore, physicians still opt to target cancer via other forms of immunotherapies, adjuvant and neoadjuvant therapies including chemotherapy, drug consumption, and surgery. As clinical results for CAR T cell therapy have not presented prosperous results in targeting solid tumors, the future for research on solid tumors is still unclear. Scientists might either opt for other methods like microwave ablation, the use of TT fields, different combinations of current therapies to maximize efficiency, and ADCs.