CD274 and cancer: Interestingly, the chronic response of T cells to a prolonged stimulus such as cancer has been defined as T cell exhaustion [265]; moreover, the density of exhausted T and B cells, as well as T-cell exhaustion–related genes like PDL1, B7H3, FOXO1, and PRDM1, correlates with a high expression of HIF-1α in glioblastoma [200].