title: Arrest in metaphase and anatomy of mitotic catastrophe: mild heat shock in two human osteosarcoma cell lines.
abstract: The exits from metaphase arrest and anatomy of mitotic catastrophe were studied in two human osteosarcoma cell lines, nontumorigenic HOS TE85 and its chemically transformed strain MNNG-HOS, applying mild genotoxic damage by heat shock at 41.8 degrees C for 24 h. Under these conditions, both cell lines doubled or tripled their mitotic index entering arrest in metaphase. On return to 37 degrees C, the arrest was either released or ended in apoptosis. The transformed strain showed a greater capacity to arrest in metaphase as well as a greater probability of developing the third pathway: to restitute this arrest in polyploid interphase. This, in turn, either entered an 'endocycle' or, following a delay, apoptosis. Thus, arrest in metaphase was a cross-point of the mitotic cycle, apoptosis, and endocycle. Mitotic catastrophe can morphologically manifest combinations of elements of these three processes.
authors.affiliation: A. Kirchenstein Institute of Microbiology and Virology, Riga, Latvia.
authors.forename: J E
authors.initials: JE
authors.lastname: Erenpreisa
authors.forename: A
authors.initials: A
authors.lastname: Ivanov
authors.forename: G
authors.initials: G
authors.lastname: Dekena
authors.forename: A
authors.initials: A
authors.lastname: Vitina
authors.forename: R
authors.initials: R
authors.lastname: Krampe
authors.forename: T
authors.initials: T
authors.lastname: Freivalds
authors.forename: G
authors.initials: G
authors.lastname: Selivanova
authors.forename: H I
authors.initials: HI
authors.lastname: Roach
mesh_terms: D000705:Anaphase; D017209:Apoptosis; D004247:DNA / Q000378:metabolism; D015726:Giant Cells / Q000502:physiology; D006358:Hot Temperature; D006801:Humans; D008677:Metaphase; D008938:Mitosis; D008954:Models, Biological; D012516:Osteosarcoma / Q000378:metabolism*; D013692:Telophase; D013997:Time Factors; D014407:Tumor Cells, Cultured
chemical_list: D004247:DNA