title: Kinetics of the human medulloblastoma cell line, D283 Med, maintained in an organ culture system. Autoradiographic study after cumulative labelling in vitro: similarities to the kinetics of human medulloblastoma in situ.
abstract: Cells of the human D283 Med medulloblastoma cell line were collected by gravity sedimentation and maintained in vitro in an organ culture system. The explants grew as clusters of small cells with scanty cytoplasm; some cells were arranged in solid trabeculae, sometimes forming rows and columns, and occasionally rosettes. The kinetic parameters were estimated after 6 days in vitro by cumulative labelling of the cultures with tritiated thymidine in three different experiments. The length of G2 phase (TG2) was obtained from an analysis of the fractions of continuously labelled mitoses (FCLM), the length of S phase (TS) from the median values of grains over mitotic figures (grain index, GI), and the other parameters from mathematical models that related growth fraction (GF), TG2, total cell cycle time (TC) and labelling index (LI) as a function of time. Mean GF, TC, TG1, TS and TG2 were estimated respectively to be 0.35, 30 h, 13 h, 10 h, and 7 h. These estimates correspond to those reported for human medulloblastomas in situ and confirm previous in vitro experiments which suggest that the organ culture technique is a suitable system for the study of cell kinetics in human malignant gliomas and for an analysis of the in vitro effects of chemotherapeutic agents.
authors.affiliation: Department of Pathology, University of Virginia School of Medicine, Charlottesville 22908.
authors.forename: Y
authors.initials: Y
authors.lastname: Nakagawa
authors.forename: M M
authors.initials: MM
authors.lastname: Herman
authors.forename: J C
authors.initials: JC
authors.lastname: Boyd
authors.forename: L J
authors.initials: LJ
authors.lastname: Rubinstein
mesh_terms: D001345:Autoradiography; D002453:Cell Cycle; D002455:Cell Division; D002460:Cell Line; D002528:Cerebellar Neoplasms / Q000378:metabolism* / Q000473:pathology; D006801:Humans; D008527:Medulloblastoma / Q000378:metabolism* / Q000473:pathology; D013936:Thymidine / Q000493:pharmacokinetics; D014407:Tumor Cells, Cultured / Q000166:cytology*
chemical_list: D013936:Thymidine