The rise of viperin: the emerging role of viperin in cancer progression

Viperin, an IFN-regulated gene product, is known to inhibit fatty acid beta-oxidation in the mitochondria, which enhances glycolysis and lipogenesis during viral infections. Yet, its role in altering the phenotype of cancer cells has not been established. In this issue of the JCI, Choi, Kim, and co-authors report on a role of viperin in regulating metabolic alterations in cancer cells. The authors showed a correlation between clinical outcomes and viperin expression levels in multiple cancer tissues and proposed that viperin expression was upregulated in the tumor microenvironment via the JAK/ STAT and PI3K/AKT/mTOR/HIF-1 alpha pathways. Functionally, viperin increased lipogenesis and glycolysis in cancer cells by inhibiting fatty acid beta-oxidation. Viperin expression also enhanced cancer stem cell properties, ultimately promoting tumor initiation in murine models. This study proposes a protumorigenic role for viperin and identifies HIF-1 alpha as a transcription factor that increases viperin expression under serum starvation and hypoxia.