TNF and malignant colon neoplasm: Metformin was shown to inhibit TNF-α-induced IL-1β and IL-8 expression and nuclear factor (NF)-κB signaling in human colon cancer cell line COLO 0205.27 The same study speculated that metformin might attenuate intestinal inflammation via adenosine monophosphate-activated protein kinase (AMPK) activation and subsequent NF-κB suppression.