PD-L1 expression can be induced by both types I and II IFNs, IL-10, and TNF-α on microvascular endothelial cells.34 PD-L1 expressing macrophages and myeloid derived suppressor cells (MDSCs) can be induced with the coculture of bladder tumour cells through COX2/mPGES1/PGE2 pathway.35 The studies on the regulation of PD-L1 expression among different tumour cells seem to get more attention. This evidence concerns the gene CD274 and urinary bladder neoplasm.