We observed the down-regulation of NF-κB pathway in terms of IKKα and I-κB expression in TAM by EGCG or EGCG-treated exosomes in vivo and ex vivo, which we think would be the molecular mechanism underling the EGCG-mediated hindrance of infiltration and differentiation of macrophages into tumor-promoting M2 macrophages, although direct evidences are lacking. The gene discussed is CHUK; the disease is neoplasm.