MTHFD2 KD suppressed both basal and IFN-γ-elevated PD-L1 (Fig. 3a, b), indicating high basal level of tumor MTHFD2 plus IFN-γ-elevated MTHFD2 both contribute to PD-L1 expression during IFN-γ stimulation. The gene discussed is IFNG; the disease is neoplasm.