a protective role by interleukin-17f in colon tumorigenesisinterleukin-17f在结肠肿瘤发生的保护作用.pdfVIP

A Protective Role by Interleukin-17F in Colon Tumorigenesis 1 . 2,3. 1 1 2 2 4 Zan Tong * , Xuexian O. Yang , Huichao Yan , Weihuang Liu , Xiaoyin Niu , Yun Shi , Wenfeng Fang , 4 1 2 Bing Xiong , Yu Wan , Chen Dong * 1 School of Basic Medical Science, Wuhan University, Wuhan, China, 2 Department of Immunology, Center for Inflammation and Cancer, M. D. Anderson Cancer Center, Houston, Texas, United States of America, 3 Health Sciences Center, University of New Mexico, Albuquerque, New Mexico, United States of America, 4 Department of Oncology, Wuhan University, Zhongnan Hospital, Wuhan, China Abstract Interleukin-17F (IL-17F), produced by Th17 cells and other immune cells, is a member of IL-17 cytokine family with highest homology to IL-17A. IL-17F has been shown to have multiple functions in inflammatory responses. While IL-17A plays important roles in cancer development, the function of IL-17F in tumorigenesis has not yet been elucidated. In the current study, we found that IL-17F is expressed in normal human colonic epithelial cells, but this expression is greatly decreased in colon cancer tissues. To examine the roles of IL-17F in colon cancer, we have used IL-17F over-expressing colon cancer cell lines and IL-17F-deficient mice. Our data showed decreased tumor growth of IL-17F-transfected HCT116 cells comparing to mock transfectants when transplanted in nude mice. Conversely, there were increased colonic tumor numbers and tumor areas in Il-17f2/ 2 mice than those from wild-type controls after colon cancer induction. These results indicate that IL-17F plays an inhibitory role in colon tumorigenesis in vivo. In IL-17F over-expressing tumors, there was no signi