title: Prediction of in vivo synergistic activity of antiangiogenic compounds by gene expression profiling.
abstract: Angiogenesis, an essential phenotype for tumor formation, requires the interaction of many cells within the tumor microenvironment. Therefore, successful antiangiogenic therapies must be able to block all of the different mechanisms tumors use to induce neovascularization. A major challenge for developing such protocols is determining which agents are likely to have the highest degree of synergistic activity in vivo. We treated human microvascular endothelial cells with six inhibitors of angiogenesis and used microarrays to seek divergent patterns of gene expression suggestive of potential synergies. The expression profiles of a thrombospondin-mimetic peptide (DI-TSPa) and TNP-470 (TNP) were very similar, whereas endostatin had a dramatically different profile. In vitro, endostatin was synergistically antiangiogenic with either TNP-470 or DI-TSPa. In vivo, mice bearing Lewis lung carcinoma cells treated with a combination of endostatin and either DI-TSPa or TNP-470, at doses that were ineffective when used alone, resulted in a marked inhibition of tumor growth and decreased tumor angiogenesis. Conversely, animals treated with both DI-TSPa and TNP-470 demonstrated a modest effect on both tumor growth and angiogenesis. These results suggest that even in the absence of a complete mechanistic understanding of how these inhibitors work, gene expression profiling may be used to predict synergistic antiangiogenic activity and thus maximize their antitumor efficacy.
authors.affiliation: The Cardinal Bernardin Cancer Center, Loyola University Medical Center, Maywood, Illinois 60153, USA.
authors.forename: Edith I
authors.initials: EI
authors.lastname: Cline
authors.forename: Silvio
authors.initials: S
authors.lastname: Bicciato
authors.forename: Carlo
authors.initials: C
authors.lastname: DiBello
authors.forename: Mark W
authors.initials: MW
authors.lastname: Lingen
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology*; D018827:Carcinoma, Lewis Lung / Q000098:blood supply / Q000188:drug therapy; D002478:Cells, Cultured; D004357:Drug Synergism; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D020869:Gene Expression Profiling; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000188:drug therapy / Q000235:genetics; D018919:Neovascularization, Physiologic / Q000187:drug effects / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D011237:Predictive Value of Tests
chemical_list: D020533:Angiogenesis Inhibitors