title: CD98 expression modulates intestinal homeostasis, inflammation, and colitis-associated cancer in mice.
abstract: Expression of the transmembrane glycoprotein CD98 (encoded by SLC3A2) is increased in intestinal inflammatory conditions, such as inflammatory bowel disease (IBD), and in various carcinomas, yet its pathogenetic role remains unknown. By generating gain- and loss-of-function mouse models with genetically manipulated CD98 expression specifically in intestinal epithelial cells (IECs), we explored the role of CD98 in intestinal homeostasis, inflammation, and colitis-associated tumorigenesis. IEC-specific CD98 overexpression induced gut homeostatic defects and increased inflammatory responses to DSS-induced colitis, promoting colitis-associated tumorigenesis in mice. Further analysis indicated that the ability of IEC-specific CD98 overexpression to induce tumorigenesis was linked to its capacity to induce barrier dysfunction and to stimulate cell proliferation and production of proinflammatory mediators. To validate these results, we constructed mice carrying conditional floxed Slc3a2 alleles and crossed them with Villin-Cre mice such that CD98 was downregulated only in IECs. These mice exhibited attenuated inflammatory responses and resistance to both DSS-induced colitis and colitis-associated tumorigenesis. Together, our data show that intestinal CD98 expression has a crucial role in controlling homeostatic and innate immune responses in the gut. Modulation of CD98 expression in IECs therefore represents a promising therapeutic strategy for the treatment and prevention of inflammatory intestinal diseases, such as IBD and colitis-associated cancer.
authors.affiliation: Department of Medicine, Emory University, Atlanta, Georgia, USA. hnguye9@emory.edu
authors.forename: Hang Thi Thu
authors.initials: HT
authors.lastname: Nguyen
authors.forename: Guillaume
authors.initials: G
authors.lastname: Dalmasso
authors.forename: Leif
authors.initials: L
authors.lastname: Torkvist
authors.forename: Jonas
authors.initials: J
authors.lastname: Halfvarson
authors.forename: Yutao
authors.initials: Y
authors.lastname: Yan
authors.forename: Hamed
authors.initials: H
authors.lastname: Laroui
authors.forename: Doron
authors.initials: D
authors.lastname: Shmerling
authors.forename: Tiziano
authors.initials: T
authors.lastname: Tallone
authors.forename: Mauro
authors.initials: M
authors.lastname: D'Amato
authors.forename: Shanthi V
authors.initials: SV
authors.lastname: Sitaraman
authors.forename: Didier
authors.initials: D
authors.lastname: Merlin
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D049109:Cell Proliferation; D002470:Cell Survival; D003092:Colitis / Q000378:metabolism*; D027282:Fusion Regulatory Protein 1, Heavy Chain / Q000378:metabolism*; D027261:Fusion Regulatory Protein-1 / Q000096:biosynthesis*; D005786:Gene Expression Regulation; D006706:Homeostasis; D007249:Inflammation; D007413:Intestinal Mucosa / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009369:Neoplasms / Q000378:metabolism*; D011110:Polymorphism, Genetic
chemical_list: D027282:Fusion Regulatory Protein 1, Heavy Chain; D027261:Fusion Regulatory Protein-1; C523212:Slc3A2 protein, mouse