Abstract 4312: Identification of putative stem cell markers of CD133 and CD44 in human ovarian cancer specimens and ovarian cancer cell lines

Abstract

Abstract Objective: Ovarian cancer may arise from a subpopulation of CD133+ 44+ cells, which are self-renewing tumor-initiating cells. Materials and Methods: We investigated the tumorigenicity of the cell line A2780 which is CD133high44low, the cell line A2780 with siRNA against CD133 (CD133low44low), and human ovarian cancer cells from ascites, from primary ovarian cancer, and from metastatic ovarian cancer (CD133 high/CD44high) harvested from patients at the time of surgical cytoreduction in ultra low attachment plates in serum free medium. Spheroids from each of these sources were used to test their tumorigenicity in SCID mice. Results: Cells from A2780 cell line (CD133 high/CD44low) formed tumors in SCID mice in 2 months but silencing CD133 with siRNA CD133 (CD133 low/CD44low) inhibited tumorigenicity in SCID mice and retarded but did not prevent spheroid formation. Spheroid cultures of ascites, primary ovary, and metastasis (CD133 high/CD44high) are capable of inducing primary ovarian tumors and metastatic tumors in SCID mice in 2 months compared to 4-6 months in sorted, non-spheroid cells. Conclusions: The data suggest that CD133 expression is necessary for tumorigenesis in the A2780 cell line but not for spheroid formation. Our data also suggests that spheroids which are CD133 high/CD44high from human tumor recapitulate ovarian cancer in women. These novel in vivo and vitro models may offer useful tools to develop therapies targeted to ovarian cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4312.