The search focused on studies containing key terms including Fusobacterium nucleatum, Helicobacter pylori, colorectal cancer, gastric cancer, CagA, FadA, VacA, NF-κB, immune evasion, red meat, processed meat, dietary carcinogens, reactive oxygen species, gut microbiota, and tumor microenvironment. The gene discussed is NFKB1; the disease is gastric cancer.