title: Tubeimoside-1 suppresses tumor angiogenesis by stimulation of proteasomal VEGFR2 and Tie2 degradation in a non-small cell lung cancer xenograft model.
abstract: Tubeimoside-1 (TBMS1) is a potent anti-tumor phytochemical. Its functional and molecular mode of action, however, remains elusive so far. Since angiogenesis is essential for tumor progression and metastasis, we herein investigated the anti-angiogenic effects of the compound. In a non-small cell lung cancer (NSCLC) xenograft model we found that treatment of CD1 nu/nu mice with TBMS1 (5 mg/kg) significantly suppressed the growth and vascularization of NCI-H460 flank tumors. Moreover, TBMS1 dose-dependently reduced vascular sprouting in a rat aortic ring assay. In vitro, TBMS1 induced endothelial cell apoptosis without decreasing the viability of NSCLC tumor cells and inhibited the migration of endothelial cells by disturbing their actin filament organization. TBMS1 further stimulated the proteasomal degradation of vascular endothelial growth factor receptor-2 (VEGFR2) and Tie2 in endothelial cells, which down-regulated AKT/mTOR signaling. These findings indicate that TBMS1 represents a novel phytochemical for anti-angiogenic treatment of cancer and other angiogenesis-related diseases.
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Gu
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Körbel
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Scheuer
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Anca
authors.initials: A
authors.lastname: Nenicu
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Menger
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, Homburg/Saar 66421, Germany.
authors.forename: Matthias W
authors.initials: MW
authors.lastname: Laschke
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D051379:Mice; D009389:Neovascularization, Pathologic; D051381:Rats; D042787:Receptor, TIE-2 / Q000235:genetics / Q000378:metabolism*; D012503:Saponins / Q000008:administration & dosage / Q000627:therapeutic use*; D015398:Signal Transduction; D014315:Triterpenes / Q000008:administration & dosage / Q000627:therapeutic use*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000235:genetics / Q000378:metabolism*; D023041:Xenograft Model Antitumor Assays
chemical_list: D012503:Saponins; D014315:Triterpenes; C051084:tubeimoside I; D042787:Receptor, TIE-2; C079086:Tek protein, mouse; D040301:Vascular Endothelial Growth Factor Receptor-2
keywords: Tie2; VEGFR2; angiogenesis; tubeimoside-1; tumor