Conclusion
There are challenges associated with CAR-T cell therapy that can be addressed by genome editing technology. CRISPR/Cas9 has been a helpful tool for the success of CAR-T cell therapy against different tumor cells. This novel genome-editing technology addressed the problem lies in the clinical use of allogeneic donor T cells, which led to GVHD in the recipient. CRISPR/Cas9 can reduce the potential GVHD caused by allogeneic CAR-T cells through eliminating TRAC and HLA loci. This approach would draw the concept of the development of off-the-shelf CAR-T cells, which could be applied in different individuals regardless of HLA matches between donor and recipient. CAR-T cell performance has been improved by disrupting inhibitory molecules, such as PD-1 and TGF- β. Given the early positive outcome of the CRISPR/Cas9 edited CAR-T cells, there appear to be numerous opportunities for new cancer therapy. The annual market value for successful cancer therapy exceed billions of US dollars, and this encourages academic as well as the pharmaceutical industry further research into this technology for the treatment of unmet clinical need in many diseases.