VEGF Targeting in Mesotheliomas Using an Interleukin-6 Signal Inhibitor Based on Adenovirus Gene Delivery

Malignant mesotheliomas reportedly secrete interleukin-6 (IL-6) which augments production of vascular endothelial growth factor (VEGF) from mesothelioma cells. We previously reported the development of a new receptor inhibitor of IL-6 (NRI) by genetically engineering tocilizumab, a humanized anti-IL-6 receptor monoclonal antibody. Since NRI is encoded on a single gene, it is easily applicable to a gene delivery system using virus vehicles. In this study, we report VEGF targeting through NRI expression based on adenovirus-mediated gene delivery in mesothelioma cells. We constructed an NRI expression vector in the context of a tropism-modified adenovirus vector that had enhanced infectivity in mesothelioma cells. This virus effectively induced NRI secretion from mesothelioma cells. This virus infection also reduced the VEGF production in mesothelioma cells. These results indicate that NRI shows potential as an agent in the treatment of mesotheliomas.