IL-1a increased PD-L1 protein expression by ≥5 MFI in 6 of 14 tumor cell lines tested; notably, the effect of combining IL-1a with IFN-g was more than additive in 12 of 14 tumor cell lines, suggesting the cooperation of distinct signaling pathways (Additional file 8: Table S4). This evidence concerns the gene IFNG and neoplasm.