CD274 and cancer: As interferon-γ results in PD-L1 expression by surrounding cells that express surface interferon receptors, PD-L1 expression is frequently detected on non-cancer cells such as lymphocytes and macrophages in the tumour microenvironment, and on T cells, with PD-L1 expression being equal or higher in the normal immune cells compared to the tumour cells [60,61,62].