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Prof.dr. Martine Smit in Science Signaling

Prof.dr. Martine Smit published an article in Science Signaling titled: 'HCMV-encoded chemokine receptor US28 mediates proliferative signaling through the IL-6-STAT3 axis'

A Viral Pathway to Tumor Development
Human cytomegalovirus (HCMV), a widespread human herpesvirus that persists in a latent form, is associated with pathological processes in immunocompromised hosts and has been implicated in the development of several forms of cancer, including glioblastoma. HCMV encodes a G protein-coupled receptor, US28, that resembles a chemokine receptor and constitutively activates signaling pathways associated with cell proliferation. Slinger et al. expressed US28 in cultured cells to explore the mechanisms through which it could promote tumor development. They found that US28 stimulated the production and secretion of both vascular endothelial growth factor (VEGF) and of the cytokine interleukin-6 (IL-6), and defined a signaling pathway whereby US28 increased cell proliferation through IL-6-dependent activation of the JAK1-STAT3 axis. IL-6 is itself a target of STAT3, leading the authors to propose that US28-dependent production and secretion of IL-6 and consequent autocrine and paracrine STAT3 activation leads to establishment of a positive feedback loop that promotes proliferation of both infected and neighboring cells.  Analyses of human glioblastoma tissue revealed US28 and activated STAT3 in cells lining blood vessels, suggesting that US28 may play a role in tumor vascularization.

An interview with prof. dr. Martine Smit about this article can be found here.