TNF‑α inhibits xenograft tumor formation by A549 lung cancer cells in nude mice via the HIF‑1α/VASP signaling pathway.

Lung cancer is the leading cause of cancer‑associated mortality worldwide. Tumor necrosis factor α (TNF‑α) is an important cytokine in the tumor microenvironment that serves a function in the balance of cell survival and cell death pathways. Our previous studies indicated that hypoxia‑inducible factor 1α (HIF‑1α) acts downstream of TNF‑α in MCF‑7 luminal breast cancer cells. However, whether vasodilator‑stimulated phosphoprotein (VASP) is implicated in the direct regulation of HIF‑1α in response to TNF‑α in lung cancer remains unknown. In vitro studies were performed using A549 and H226 lung carcinoma cells and in vivo studies of tumor xenograft models were performed to investigate the effects of TNF‑α. The results demonstrated that TNF‑α decreased VASP expression by upregulating the expression of HIF‑1α to inhibit A549 cell proliferation and adhesion. Inhibition of transplanted tumor growth was associated with downregulation of VASP expression in nude mice. Bioinformatics analysis indicated that expression levels of VASP or HIF‑1α lead to differential outcomes of overall survival in lung carcinoma. These results suggest that the HIF‑1α/VASP signaling pathway serves an important function in the regulation of TNF‑α‑induced suppression of A549 cell proliferation and xenograft growth. This may improve our understanding of the antitumor effect of TNF‑α.