RT Journal Article SR Electronic T1 Is Troponin I Gene Therapy Effective for Osteosarcoma Treatment? Study on a Human-like Orthotopic Rat Model JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 3977 OP 3982 VO 24 IS 6 A1 A. DUTOUR A1 H. RABINOVICH-CHABLE A1 C. KALETTA A1 U. MICHAELIS A1 F. FIORENZA A1 F. STURTZ A1 M. RIGAUD YR 2004 UL http://ar.iiarjournals.org/content/24/6/3977.abstract AB Background: An anti-angiogenesis strategy has been widely recognized as a viable approach to fight cancer and more and more anti-angiogenic factors are continually being identified. Among them, the muscular isoform of Troponin I (TnI) has been described as being a powerful anti-angiogenic agent in vitro as well as in vivo. We investigated the therapeutic efficacy of TnI gene therapy in a human-like orthotopic rat osteosarcoma model. Materials and Methods: In this tumor model, we evaluated whether the administration of the secreted TnI coding sequence complexed to cationic liposomes (named TnITag cDNA/lCLP) could induce a delay in tumor growth and reduce tumor vasculature. Results: Although TnI specifically inhibited endothelial cell growth in vitro, we were not able to demonstrate any therapeutic efficacy of TnI in the transplantable osteosarcoma model. Conclusion: This lack of efficacy probably resulted from the rapid degradation of recombinant TnI by matrix metalloproteinases, especially MMP2, which are present in large amounts in tumors. Copyright© 2004 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved