Abstract 5025: Presence of meningioma stroma mesenchymal stem-like cells.

Abstract Presence of cells resembling bone marrow-mesenchymal stem cells (BM-MSCs) from glioma was proved, however it has been little known about existence of MSCs from meningioma. We try to investigate whether we are able to isolate cells resembling BM-MSCs. Thus, we hypothesized that cells similar to BM-MSCs exist in meningioma specimen. We cultured fresh meningioma specimen using the same protocols for culturing BM-MSCs. The cultured cells were analyzed by fluorescence-activated cell sorting (FACS) for surface markers associated with BM-MSCs. These cells were exposed to mesenchymal differentiation conditions. To evaluate the tumorigenecity of cells resembling MSCs from meningioma, we injected these cells into the brain of athymic nude mice. To find possible locations, sections of meningioma specimens were analyzed by immunofluorescent labeling. In 5 of 17 meningioma specimen, we isolated cells similar to BM-MSCs which were called meningioma stroma mesenchymal stem-like cells (MS-MSCs). MS-MSCs were spindle shaped and adherent cells. FACS analysis showed that the MS-MSCs had similar surface marker to BM-MSCs. (Cells that were positive for two of the markers among CD105, CD90, CD73 and negative for two of the markers among CD45, CD31, NG2 were chosen to see their differentiation capability.) Chosen cells were observed for their ability to differentiate into adipocytes, osteocytes and chondrocytes. MS-MSCs immnohistological analysis indicated that were closely associated with the endothelial cells and pericytes cells. No tumor was discovered within the brains of mice that received the MS-MSCs orthotopic inoculation. Our results recognized that cells similar to BM-MSCs exist in meningioma specimen for the first time. MS-MSCs could be a source of meningioma microenvironment. Citation Format: Eui Hyun Kim, Seok Ku Kang. Presence of meningioma stroma mesenchymal stem-like cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5025. doi:10.1158/1538-7445.AM2013-5025 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.