Tumor progression rate of B16IDO tumors was delayed in AHR deficient mice (AHRKO) (Supplementary Fig. 3f) and depletion of macrophages with αCSF1-R (Supplementary Fig. 3g–h) or clodronate liposomes (Fig. 2g) delayed the progression of IDO-expressing tumors but not wild-type tumors. This evidence concerns the gene AHR and neoplasm.