Beyond direct epithelial effects, Fusobacterium nucleatum profoundly reshapes the immune milieu: it drives M2 polarization of tumor-associated macrophages via NF-κB activation and stimulates the secretion of pro-tumorigenic cytokines such as IL-8, CXCL1, IL-1β, IL-6, and TNF-α, thereby sustaining a chronic inflammatory and immunosuppressive microenvironment (Figure 1). This evidence concerns the gene NFKB1 and neoplasm.