TNF and neoplasm: Expression of the rate-limiting IDO1 is induced in myeloid-lineage cells by IFNs, particularly Type II, and TNF can act synergistically to increase IDO1 expression [71], so the observed down-regulation of these pathways in NuKO cells combined with the moderate up-regulation of the negative effectors DAP12 (TYROBP) and BIN1, a tumor suppressor, (S3 Table) [72] would be expected to reduce IDO1 expression substantially.