Hypothesizing that PA metabolites can be immunosuppressive, the “combined” gene set was informatically and empirically defined using PA genes that were negatively correlated with both Bindea cytotoxic lymphocyte gene set (CTL) and REACTOME IFNγ gene set ssGSEA scores across multiple TCGA T cell–infiltrated tumor types (Supplementary Figs. S4A and S4B; ref. 32). Here, IFNG is linked to neoplasm.