title: Suppression of tumor growth and metastasis in Mgat5-deficient mice.
abstract: Golgi beta1,6N-acetylglucosaminyltransferase V (MGAT5) is required in the biosynthesis of beta1,6GlcNAc-branched N-linked glycans attached to cell surface and secreted glycoproteins. Amounts of MGAT5 glycan products are commonly increased in malignancies, and correlate with disease progression. To study the functions of these N-glycans in development and disease, we generated mice deficient in Mgat5 by targeted gene mutation. These Mgat5-/- mice lacked Mgat5 products and appeared normal, but differed in their responses to certain extrinsic conditions. Mammary tumor growth and metastases induced by the polyomavirus middle T oncogene was considerably less in Mgat5-/- mice than in transgenic littermates expressing Mgat5. Furthermore, Mgat5 glycan products stimulated membrane ruffling and phosphatidylinositol 3 kinase-protein kinase B activation, fueling a positive feedback loop that amplified oncogene signaling and tumor growth in vivo. Our results indicate that inhibitors of MGAT5 might be useful in the treatment of malignancies by targeting their dependency on focal adhesion signaling for growth and metastasis.
authors.affiliation: Samuel Lunenfeld Research Institute, Mount Sinai Hospital 600 University Ave. R988, Toronto, Ontario, Canada M5G 1X5.
authors.forename: M
authors.initials: M
authors.lastname: Granovsky
authors.forename: J
authors.initials: J
authors.lastname: Fata
authors.forename: J
authors.initials: J
authors.lastname: Pawling
authors.forename: W J
authors.initials: WJ
authors.lastname: Muller
authors.forename: R
authors.initials: R
authors.lastname: Khokha
authors.forename: J W
authors.initials: JW
authors.lastname: Dennis
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002277:Carcinoma / Q000201:enzymology / Q000473:pathology; D003433:Crosses, Genetic; D005260:Female; D018226:Fibroadenoma / Q000201:enzymology / Q000473:pathology; D006056:Golgi Apparatus / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000473:pathology* / Q000517:prevention & control*; D051379:Mice; D018345:Mice, Knockout; D008969:Molecular Sequence Data; D016296:Mutagenesis; D017351:N-Acetylglucosaminyltransferases / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D009362:Neoplasm Metastasis; D011134:Polysaccharides / Q000096:biosynthesis* / Q000737:chemistry; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D011134:Polysaccharides; D011994:Recombinant Proteins; D017351:N-Acetylglucosaminyltransferases; C052254:alpha-1,6-mannosylglycoprotein beta 1,6-N-acetylglucosaminyltransferase