Abstract 1417: Role of the matricellular protein SPARC in breast tumor growth and metastatic dissemination

Breast cancer is the leading cause of death on women worldwide. Whereas surgical resection and adjuvant therapy can cure well-confined primary tumors, metastatic disease is largely incurable because of its systemic nature and the resistance of disseminated tumor cells to existing therapeutic agents. SPARC (Secreted Protein Acidic and Rich in Cystein) is a matricellular protein whose normal expression is associated with remodeling tissues. In this context SPARC was described as involved in cell cycle and proliferation, invasion, adhesion, migration, angiogenesis and apoptosis. Expression array technology among other approaches identified SPARC as marker of poor prognosis, very often associated with most aggressive tumors in the vast majority of human cancer types. However, there is confusing data regarding the role of this protein during the development and progression of breast tumors. In order to achieve a better understanding of the role of this protein during breast cancer progression, we used the murine metastatic breast cancer model, 4T1. We found that silencing SPARC in these epithelial cells, after transduction with a lentiviral vector carrying a siRNA against murine SPARC, results in the completely loss of their metastatic capability (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1417. doi:1538-7445.AM2012-1417