CD274 and cancer: Cancers have been categorized into 4 different tumor microenvironments based on the presence of TILs and PD-L1 expression, among which, Type I tumors (PD-L1+, TILs+) are most likely to benefit from anti-PD-1/L1 blockade, as these tumors are warm tumors with pre-existing intratumor T cells [7].