title: Micronucleus formation in human tumour cells: lack of correlation with radiosensitivity.
abstract: The micronucleus (MN) test has been carefully characterized in four human tumour cell lines of widely differing radiosensitivity. Two radioresistant bladder carcinoma cell lines (MGH-U1 and RT112), one sensitive medulloblastoma cell line (D283MED) and a sensitive neuroblastoma cell line (HX142) were used. The number of MN per Gy of ionising radiation was 0.13 for HX142, 0.17 for D283MED, 0.21 for RT112 and 0.26 for MGH-U1. This does not rank the cell lines in the same order of radiosensitivity as clonogenic cell survival where the surviving fraction at 2 Gy (SF2) was 0.11 for HX142, 0.2 for D283MED, 0.62 for RT112 and 0.53 for MGH-U1. This discrepancy between MN formation and cell death leaves doubt as to the potential usefulness of the MN test as a rapid assay of radiosensitivity but it has potential implications for the mechanistic basis of radiosensitivity in these cells.
authors.affiliation: Radiotherapy Research Unit, Institute of Cancer Research, Sutton, Surrey, UK.
authors.forename: C
authors.initials: C
authors.lastname: Bush
authors.forename: T J
authors.initials: TJ
authors.lastname: McMillan
mesh_terms: D016923:Cell Death / Q000187:drug effects / Q000528:radiation effects; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000528:radiation effects; D003571:Cytochalasin B / Q000494:pharmacology; D006801:Humans; D008527:Medulloblastoma / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy; D048629:Micronuclei, Chromosome-Defective / Q000187:drug effects / Q000528:radiation effects*; D009369:Neoplasms / Q000235:genetics* / Q000473:pathology / Q000532:radiotherapy*; D009447:Neuroblastoma / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy; D011836:Radiation Tolerance / Q000502:physiology*; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000473:pathology / Q000532:radiotherapy
chemical_list: D003571:Cytochalasin B