CEACAM1 and neoplasm: The lack of association with a favorable outcome might be explained by the ability of F. nucleatum to inhibit T and NK cell killing of tumor cells by binding and activating the inhibitory receptors TIGIT45 and CEACAM1 (ref. 46) or by induction of IL-8-mediated myeloid activation47 (Extended Data Fig. 8 and Supplementary Fig. 11).