gms | German Medical Science

Objective: In general meningiomas can be cured by resection or radiotherapy, but there are no alternative therapy methods neither for high-grade meningiomas, nor for recurrences of all meningioma types as well as surgically not removable tumors. Primary meningioma cell cultures from human tumor tissue present an attractive model for research on alternative therapy options. This study analyses whether those cultivated cells are of meningeal origin and if their cytobiological characteristics correlate with the initial histopathological report.

Method: Cell cultures acquired from tumor tissue were microscopically analysed. Meningeal origin was determined by staining for EMA, vimentin, nestin, and TE7. Primary cell cultures were characterized by cytobiological features (growth kinetics, senescence, migration, colony formation) and chemosensitivity to ethanol and DMSO. Pro-proliferative properties were determined by analysis of MAP/PI3-kinase and RTK-signalling pathway markers. Generation times were correlated with histopathological grading and immunocytochemical staining of Ki67 and WHO-grades were related growth kinetics as well as to signalling pathways.

Results: Out of 49 meningioma specimen (31 I°, 15 II°, 3 III°), 29 (59%) were successfully cultivated. All of those primary cell cultures were positive for vimentin but only 18 (62%) were clearly EMA-positive and derived initially from 9 (50%) I°, 8 (44%) II° and 1 (5.6%) III° meningioma. There were 3 primary cell cultures which showed only a slight EMA positivity but were negative for nestin and 8 cultures were negative for both EMA and nestin. Proliferation kinetics of EMA+ cultures differed to the initially reported WHO grade (mean generation time of I°: 3,2d; II°: 4,4d; III°: 7,5d). Senescence, migration and colony formation were analysed in all clearly identified meningioma cultures. Sensitivity to ethanol and DMSO varied irrespectively of the WHO grade, and likewise there was no grade dependent difference in expression of MAP/PI3K and RTK-signalling markers.

Conclusions: It was accomplished to cultivate primary meningioma cells from intraoperative tumor specimen in 37% of all operated meningiomas. Another 8% of the primary cultures were microscopically identified as meningiomas but did not completely fulfil the immunohistochemical meningioma profile criteria. Proliferation kinetics of primary cell cultures correlated with the initial WHO grade. In conclusion, primary meningioma cell cultures may be established and used for further research.