title: Inhibition of Epithelial-Mesenchymal Transition and Metastasis by Combined TGFbeta Knockdown and Metformin Treatment in a Canine Mammary Cancer Xenograft Model.
abstract: Epithelial mesenchymal transition (EMT) is a process by which epithelial cells acquire mesenchymal properties, generating metastases. Transforming growth factor beta (TGF-β) is associated with this malignancy by having the ability to induce EMT. Metformin, has been shown to inhibit EMT in breast cancer cells. Based on this evidence we hypothesize that treatment with metformin and the silencing of TGF-β, inhibits the EMT in cancer cells. Canine metastatic mammary tumor cell line CF41 was stably transduced with a shRNA-lentivirus, reducing expression level of TGF-β1. This was combined with metformin treatment, to look at effects on cell migration and the expression of EMT markers. For in vivo study, unmodified or TGF-β1sh cells were injected in the inguinal region of nude athymic female mice followed by metformin treatment. The mice's lungs were collected and metastatic nodules were subsequently assessed for EMT markers expression. The migration rate was lower in TGF-β1sh cells and when combined with metformin treatment. Metformin treatment reduced N-cadherin and increased E-cadherin expression in both CF41 and TGF-β1sh cells. Was demonstrated that metformin treatment reduced the number of lung metastases in animals bearing TGF-β1sh tumors. This paralleled a decreased N-cadherin and vimentin expression, and increased E-cadherin and claudin-7 expression in lung metastases. This study confirms the benefits of TGF-β1 silencing in addition to metformin as potential therapeutic agents for breast cancer patients, by blocking EMT process. To the best of our knowledge, we are the first to report metformin treatment in cells with TGF-β1 silencing and their effect on EMT.
authors.affiliation: Universidade Estadual Paulista "Julio de Mesquita Filho" (UNESP/IBILCE), PostGraduate Program in Genetics, Cristovao Colombo Street, 2265, Jardim Nazareth, Sao Jose do Rio Preto, SP, Brazil.|Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), Laboratory of Molecular Investigation of Cancer (LIMC), Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: Leonel
authors.affiliation: Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), Laboratory of Molecular Investigation of Cancer (LIMC), Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.|Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), PostGraduate Program in Health Sciences, Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.
authors.forename: Thaiz Ferraz
authors.initials: TF
authors.lastname: Borin
authors.affiliation: Universidade Estadual Paulista "Julio de Mesquita Filho" (UNESP/IBILCE), PostGraduate Program in Genetics, Cristovao Colombo Street, 2265, Jardim Nazareth, Sao Jose do Rio Preto, SP, Brazil.|Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), Laboratory of Molecular Investigation of Cancer (LIMC), Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.
authors.forename: Lívia
authors.initials: L
authors.lastname: de Carvalho Ferreira
authors.affiliation: Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), Laboratory of Molecular Investigation of Cancer (LIMC), Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.|Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), PostGraduate Program in Health Sciences, Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil.
authors.forename: Marina Gobbe
authors.initials: MG
authors.lastname: Moschetta
authors.affiliation: National Center for Research in Energy and Materials - CNPEM, Brazilian Biosciences National Laboratory - LNBio, Giuseppe Máximo Scolfaro Street, Campinas, SP, 10000, Brazil.
authors.forename: Marcio Chaim
authors.initials: MC
authors.lastname: Bajgelman
authors.affiliation: Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, 50 Stone Rd E, Guelph, ON, N1G 2W1, Canada.
authors.forename: Alicia M
authors.initials: AM
authors.lastname: Viloria-Petit
authors.affiliation: Universidade Estadual Paulista "Julio de Mesquita Filho" (UNESP/IBILCE), PostGraduate Program in Genetics, Cristovao Colombo Street, 2265, Jardim Nazareth, Sao Jose do Rio Preto, SP, Brazil. debora.zuccari@famerp.br.|Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), Laboratory of Molecular Investigation of Cancer (LIMC), Brigadeiro Faria Lima Avenue, 5416, Vila São Pedro, Sao Jose do Rio Preto, SP, Brazil. debora.zuccari@famerp.br.
authors.forename: Debora Aparecida Pires
authors.initials: DA
authors.lastname: de Campos Zuccari
mesh_terms: D000818:Animals; D015820:Cadherins / Q000378:metabolism; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects*; D004285:Dogs; D058750:Epithelial-Mesenchymal Transition / Q000187:drug effects*; D015674:Mammary Neoplasms, Animal / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008687:Metformin / Q000494:pharmacology*; D009361:Neoplasm Invasiveness / Q000473:pathology; D016212:Transforming Growth Factor beta / Q000378:metabolism*
chemical_list: D015820:Cadherins; D016212:Transforming Growth Factor beta; D008687:Metformin
keywords: Anticarcinogenic agents; Breast cancer; Metastasis; TGF-β; shRNA