Differential modulation by vanadium pentoxide of the secretion of CXCL8 and CXCL11 chemokines in thyroid cells

Recently it has been hypothesized that vanadium serves a carcinogenic role in the thyroid. However, to date, no in vivo or in vitro studies have evaluated thyroid disruption in humans and/or animals following exposure to vanadium. The present study evaluated the effect of vanadium pentoxide (V2O5) on cell viability and proliferation, and chemokine (C-X-C motif) ligand (CXCL)8 and CXCL11 secretion in normal thyrocytes. The results demonstrated that V2O5had no effect on thyroid follicular cell viability and proliferation. However, V2O5was able to induce the secretion of CXCL8 and CXCL11 chemokines from thyrocytes. Notably, V2O5synergistically increased the effect of the interferon (IFN)-γ on CXCL11 secretion. In addition, V2O5synergistically increased the effect of tumor necrosis factor-alpha; on CXCL8 secretion, and abolished the inhibitory effect of IFN-γ. Overall this induction of CXCL8 and CXCL11 secretion may lead to the induction and perpetuation of an inflammatory reaction in the thyroid. Further studies are now required to evaluate thyroid function and nodule development in subjects who are occupationally exposed, or living in polluted areas.