@article{open1868, volume = {197}, number = {5}, month = {September}, author = {Ravindra Gujar and Neeraj Maurya and Vinod Yadav and Mamta Gupta and Saurabh Arora and Neeraj Khatri and Pradip Sen}, note = {Copyright of this article belongs to American Association of Immunologists.}, title = {c-Src Suppresses Dendritic Cell Antitumor Activity via T Cell Ig and Mucin Protein-3 Receptor.}, publisher = {American Association of Immunologists}, year = {2016}, journal = {Journal of immunology (Baltimore, Md. : 1950)}, pages = {1650--62}, url = {http://crdd.osdd.net/open/1868/}, abstract = {The enhanced expression of T cell Ig and mucin protein-3 (TIM-3) on tumor-associated dendritic cells (DCs) attenuates antitumor effects of DNA vaccines. To identify a potential target (or targets) for reducing TIM-3 expression on tumor-associated DCs, we explored the molecular mechanisms regulating TIM-3 expression. In this study, we have identified a novel signaling pathway (c-Src{$\rightarrow$}Bruton's tyrosine kinase{$\rightarrow$}transcription factors Ets1, Ets2, USF1, and USF2) necessary for TIM-3 upregulation on DCs. Both IL-10 and TGF-{\ensuremath{\beta}}, which are produced in the tumor microenvironment, upregulated TIM-3 expression on DCs via this pathway. Suppressed expression of c-Src or downstream Bruton's tyrosine kinase, Ets1, Ets2, USF1, or USF2 blocked IL-10- and TGF-{\ensuremath{\beta}}-induced TIM-3 upregulation on DCs. Notably, in vivo knockdown of c-Src in mice reduced TIM-3 expression on tumor-associated DCs. Furthermore, adoptive transfer of c-Src-silenced DCs in mouse tumors enhanced the in vivo antitumor effects of immunostimulatory CpG DNA; however, TIM-3 overexpression in c-Src-silenced DCs blocked this effect. Collectively, our data reveal the molecular mechanism regulating TIM-3 expression in DCs and identify c-Src as a target for improving the efficacy of nucleic acid-mediated anticancer therapy.} }