CD274 and melanoma: To further assess whether ABZ regulates tumor PD-L1 levels in vitro, human melanoma cells A375 and SK-MEL-28 and human lung cancer cells A549 were pretreated with IFN-γ to increase PD-L1 levels, human lung cancer cell line H460 and mouse melanoma cells B16F10, which were highly expressed PD-L1 without IFN-γ treatment, followed by treatment with ABZ.