Cancer treatment – thinking beyond CAR T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy is a type of immunotherapy which has gained a lot of attention in recent years. This therapy relies on a chimeric T-cell receptor first introduced in 1987. This discovery led to a development of the first generation CARs by an Israeli immunologist Zelig Eshhar in 1993. Since then, genetically engineered T-cells possessing this chimeric receptor have been used to develop an effective, targeted treatment for various types of cancer. This extensive research resulted in the first FDA-approved CAR T-cell therapy for B-cell lymphomas in 2017. However, this treatment is mostly effective for hematological cancers while solid tumours are particularly difficult to treat. Nevertheless, in recent years there have been many advantages in this field that aimed to modify this therapy for solid tumour treatment. Such methods involve either the combination of CAR T-cell therapy with other cancer immunotherapies, or the use of other types of immune cells, such as natural killer (NK) cells and macrophages. This review article first outlines the principle of CAR T-cell therapy and then discusses new developments in this field, with a particular focus on solid tumours.