Furthermore, it was reported that the CAR T therapy led to significant increase in the level of PD-L1 expression on tumour cell surface and PD-1 expression of CAR T cells, and that a sub-toxic dose of doxorubicin was able to increase the efficacy of anti-GD2 CAR T cells and reduce tumour PD-L1 expression. This evidence concerns the gene CD274 and neoplasm.