Tumor necrosis factor-alpha promotes tumor growth by inducing vascular endothelial growth factor.

Tumor necrosis factor (TNF)-α has been proved as an adjuvant therapy for tumor by FDA. However, the effect of chronic TNF-α expression for tumor is still controversial. In this study, we investigated the effect of low-dose TNF-α on tumor growth. We confirmed that low-dose TNF-α promoted angiogenesis of tumor in vivo, vascular endothelial growth factor (VEGF) and hypoxia-inducible factor (HIF)-1α, the transcription factor of VEGF, were both upregulated. Our results suggested that low-dose TNF-α was a powerful activator of angiogenesis in tumor and HIF-1α-VEGF pathway seemed to be the most important molecular mechanism.