Abstract 1432: Tnfα ablation demonstrates no suppressive effect on inflammation-related mouse colon tumorigenesis

Abstract Colorectal cancer (CRC) is one of the most serious complications of inflammatory bowel disease. Tumor necrosis factor-α (Tnfα) is a major mediator of inflammation and there is increasing evidence that Tnfα/Tnf-receptor-1 (Tnfr1) signaling may act as an endogenous tumor promoter for colon carcinogenesis. In fact, a previous study revealed that mice lacking Tnfr1 develop significantly fewer colonic tumors in the inflammation-related CRC model. Apc Min/+;Tnfα -/- mice were treated with 2% dextran sodium sulfate (DSS) and the tumor development was compared with Apc Min/+;Tnfα +/+ control mice in order to investigate the role of Tnfα by itself in the inflammation-related CRC. Surprisingly, there were no significant differences in either the severity of colonic inflammation or the expression of DSS-induced chemokines and cytokines (Ccl2, Cxcl1, Tnfβ, Il1β, Il6, and Cox-2) that relate to the colonic inflammation and tumorigenesis between these two groups. Furthermore, the genetic ablation of Tnfα did not suppress the colon tumorigenesis in comparison to the wild-type mice. These observations suggest that redundant inflammatory responses other than the Tnfα-mediated inflammation promote tumorigenesis in the colon. These results also suggest that Tnfα alone may not be an efficient target for the prevention/ treatment of inflammation-related colon tumorigenesis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1432.