[Establishment and biological characterization of human medulloblastoma cell lines].

Two cell lines of human medulloblastoma (ONS-76 and ONS-81) were established, and their biological characteristics were investigated. The cell line, ONS-76, was established from a tumor specimens obtained from a large cerebellar tumor of a 2-year-old girl. The pathological diagnosis was a typical medulloblastoma. The other cell line, ONS-81, was derived from a metastatic tumor in right frontal lobe of a 9-year-old girl. The tumor specimens were minced into fragments approximately 1 mm in diameter and cultured in plastic culture flasks in RPMI 1640 medium supplemented with 10% heat-inactivated fetal calf serum (FCS) and 50% patients serum. The cells growing as a monolayer were subcultured in RPMI 1640 supplemented with 10% FCS and initially with L-glutamine, sodium pyruvate, and nonessential amino acid. Microscopically, both cultured cells exhibited various morphological appearances, and this morphological heterogeneity seemed to be specific for medulloblastoma cells. The in vitro population doubling time of ONS-76 and ONS-81 were 18.6 and 19.2 hr, respectively. The ONS-76 and ONS-81 cells formed subcutaneous tumors in nude mice as serial transplantable xenograft, and these tumors had a microscopic appearance similar to that of the original medulloblastoma. Ultrastructurally++, the cultured cells showed primitive, undifferentiated appearance, and no neuronal or glial structures were not seen. Immunohistochemical studies showed that both cells expressed neuron-specific enolase (NSE) and neurofilament protein (NFP 200 K, 145 K), but glial fibrillary acidic protein (GFAP) and S-100 protein were not detected. The NFP immunoreactivities of both cultured cells were demonstrated as abnormal perinuclear deposits.(ABSTRACT TRUNCATED AT 250 WORDS)