TNF and neoplasm: Besides, SCFAs play an important role in maintaining homeostasis, SCFAs also increase tumor-killing CD8+ T cells and reduce immune-suppressing Tregs in tumor tissues such as that the supplements using SCFAs or SCFA-producing bacteria increase intratumor T cells and raise the concentration of cytokines interferon-γ and tumor necrosis factor-α to result in inhibition of tumor growth.118