title: A protective role by interleukin-17F in colon tumorigenesis.
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-17f(-/-) 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 significant change in leukocyte infiltration; instead, we found decreased VEGF levels and CD31(+) cells. While the VEGF levels were increased in the colon tissues of Il-17f(-/-) mice with colon cancer. Together, our findings demonstrate a protective role for IL-17F in colon cancer development, possibly via inhibiting tumor angiogenesis.
authors.affiliation: School of Basic Medical Science, Wuhan University, Wuhan, China. ztong@whu.edu.cn
authors.forename: Zan
authors.initials: Z
authors.lastname: Tong
authors.forename: Xuexian O
authors.initials: XO
authors.lastname: Yang
authors.forename: Huichao
authors.initials: H
authors.lastname: Yan
authors.forename: Weihuang
authors.initials: W
authors.lastname: Liu
authors.forename: Xiaoyin
authors.initials: X
authors.lastname: Niu
authors.forename: Yun
authors.initials: Y
authors.lastname: Shi
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Fang
authors.forename: Bing
authors.initials: B
authors.lastname: Xiong
authors.forename: Yu
authors.initials: Y
authors.lastname: Wan
authors.forename: Chen
authors.initials: C
authors.lastname: Dong
mesh_terms: D000818:Animals; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000235:genetics* / Q000378:metabolism*; D004847:Epithelial Cells / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic; D045325:HCT116 Cells; D006801:Humans; D020381:Interleukin-17 / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009389:Neovascularization, Pathologic / Q000235:genetics; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000276:immunology / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D020381:Interleukin-17; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D042461:Vascular Endothelial Growth Factor A