title: Differential Proteome Analysis Identifies TGF-β-Related Pro-Metastatic Proteins in a 4T1 Murine Breast Cancer Model.
abstract: Transforming growth factor-β (TGF-β) has a dual role in tumorigenesis, acting as either a tumor suppressor or as a pro-oncogenic factor in a context-dependent manner. Although TGF-β antagonists have been proposed as anti-metastatic therapies for patients with advanced stage cancer, how TGF-β mediates metastasis-promoting effects is poorly understood. Establishment of TGF-β-related protein expression signatures at the metastatic site could provide new mechanistic information and potentially allow identification of novel biomarkers for clinical intervention to discriminate TGF-β oncogenic effects from tumor suppressive effects. In the present study, we found that systemic administration of the TGF-β receptor kinase inhibitor, SB-431542, significantly inhibited lung metastasis from transplanted 4T1 mammary tumors in Balb/c mice. The differentially expressed proteins in the comparison of lung metastases from SB-431542 treated and control vehicle-treated groups were analyzed by a quantitative LTQ Orbitrap Velos system coupled with stable isotope dimethyl labeling. A total of 36,239 peptides from 6,694 proteins were identified, out of which 4,531 proteins were characterized as differentially expressed. A subset of upregulated proteins in the control group was validated by western blotting and immunohistochemistry. The eukaryotic initiation factor (eIF) family members constituted the most enriched protein pathway in vehicle-treated compared with SB-43512-treated lung metastases, suggesting that increased protein expression of specific eIF family members, especially eIF4A1 and eEF2, is related to the metastatic phenotype of advanced breast cancer and can be down-regulated by TGF-β pathway inhibitors. Thus our proteomic approach identified eIF pathway proteins as novel potential mediators of TGF-β tumor-promoting activity.
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan; Department of Hepatology, Graduate School of Medicine, Osaka City University, Osaka, Japan.
authors.forename: Misako
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Anatomy and Regenerative Biology, Graduate School of Medicine, Osaka City University, Osaka, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Matsubara
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Adachi
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan.
authors.forename: Yuuki
authors.initials: Y
authors.lastname: Hashimoto
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan.
authors.forename: Kazuna
authors.initials: K
authors.lastname: Fukamizu
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan.
authors.forename: Marina
authors.initials: M
authors.lastname: Kishida
authors.affiliation: Laboratory of Cancer Biology and Genetics, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Yu-An
authors.initials: YA
authors.lastname: Yang
authors.affiliation: Laboratory of Cancer Biology and Genetics, National Institutes of Health, Bethesda, Maryland, United States of America.
authors.forename: Lalage M
authors.initials: LM
authors.lastname: Wakefield
authors.affiliation: Laboratory of Proteome Research, Proteome Research Center, National Institute of Biomedical Innovation, Saito, Osaka, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tomonaga
mesh_terms: D000818:Animals; D001549:Benzamides / Q000494:pharmacology; D045744:Cell Line, Tumor; D004149:Dioxoles / Q000494:pharmacology; D039642:Eukaryotic Initiation Factors / Q000378:metabolism; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism* / Q000517:prevention & control / Q000556:secondary*; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009363:Neoplasm Proteins / Q000378:metabolism*; D020543:Proteome / Q000378:metabolism; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors; D016212:Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000378:metabolism*
chemical_list: C459179:4-(5-benzo(1,3)dioxol-5-yl-4-pyridin-2-yl-1H-imidazol-2-yl)benzamide; D001549:Benzamides; D004149:Dioxoles; D039642:Eukaryotic Initiation Factors; D009363:Neoplasm Proteins; D020543:Proteome; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta