Low‐dose TNF‐α promotes angiogenesis of oral squamous cell carcinoma cells via TNFR2/Akt/mTOR axis

Abstract

AbstractObjectivesTo assess the role of TNF‐α/TNFR2 axis on promoting angiogenesis in oral squamous cell carcinoma (OSCC) cells and uncover the underlying mechanisms.Materials and MethodsThe expression of TNFR2 and CD31 in OSCC tissues was examined; gene expression relationship between TNF‐α/TNFR2 and angiogenic markers or signaling molecules was analyzed; the expression of angiogenic markers, signaling molecules, TNFR1, and TNFR2 in TNF‐α‐stimulated OSCC cells treated with or without TNFR2 neutralizing antibody (TNFR2 Nab) were assessed; the concentration of angiogenic markers in the supernatant of OSCC cells was detected; conditioned mediums of OSCC cells treated with TNF‐α or TNF‐α + TNFR2 Nab were applied to human umbilical vein endothelial cells (HUVECs), followed by tube formation and cell migration assays.ResultsSignificantly elevated expression of TNFR2 and CD31 in OSCC tissues was observed. A positive gene expression correlation was identified between TNF‐α/TNFR2 and angiogenic markers or signaling molecules. TNFR2 Nab inhibited the effects of TNF‐α on enhancing the expression of angiogenic factors and TNFR2, the phosphorylation of the Akt/mTOR signaling pathway, HUVECs migration, and tube formation.ConclusionsTNFR2 Nab counteracts the effect of TNF‐α on OSCC cells through the TNFR2/Akt/mTOR axis, indicating that blocking TNFR2 might be a promising strategy against cancer.