title: Effect of hypoxia and TP53 mutation status and cytogenetics of normal and malignant mammary epithelium.
abstract: It has been proposed that hypoxia favors the growth of tumor cells over normal cells, particularly tumor cells carrying TP53 mutations. Cytogenetic studies of breast cancer have shown that highly complex karyotypes seen in direct harvest preparations are rarely detected after short-term culture. In this study, 34 paired samples of breast carcinomas and grossly nontumorous tissue from the same breast were cultured at 20 and 5% (12 samples) or 20 and 0% oxygen (22 samples). Both carcinoma samples and nontumorous tissue survived at 0% oxygen. Recovery for 24 hours at 20% produced good yields for cytogenetic analysis. Lower oxygen levels did not specifically stimulate growth of tumor cells. Samples with TP53 mutations showed a consistently increased growth under anaerobic hypoxic conditions. Culture at 5% oxygen did not generally reveal more karyotypic abnormalities than found at 20%. In the samples cultured at 0 and 20%, karyotypic abnormalities were detected only in anaerobic hypoxic culture in two cases. Of the only four samples where more complex karyotypes were detected in the low-oxygen culture, two were TP53 mutated. Hypoxic treatment followed by recovery at 20% oxygen may thus increase the yield of complex karyotypes from a subset of breast carcinomas, particularly those with mutated TP53.
authors.affiliation: Molecular and Cell Biology Research Laboratory, Icelandic Cancer Society, Skógarhlid 8, 105 Reykjavík, Iceland.
authors.forename: Hilmar
authors.initials: H
authors.lastname: Vidarsson
authors.forename: Margrét
authors.initials: M
authors.lastname: Steinarsdóttir
authors.forename: Jón Gunnlaugur
authors.initials: JG
authors.lastname: Jónasson
authors.forename: Hildur
authors.initials: H
authors.lastname: Júlíusdóttir
authors.forename: Halla
authors.initials: H
authors.lastname: Hauksdóttir
authors.forename: Hólmfrídur
authors.initials: H
authors.lastname: Hilmarsdóttir
authors.forename: Kristín
authors.initials: K
authors.lastname: Halldórsdóttir
authors.forename: Helga M
authors.initials: HM
authors.lastname: Ogmundsdóttir
mesh_terms: D001940:Breast / Q000378:metabolism*; D001943:Breast Neoplasms / Q000235:genetics* / Q000473:pathology; D002455:Cell Division; D015687:Cell Hypoxia; D006801:Humans; D007150:Immunohistochemistry; D007621:Karyotyping; D009154:Mutation; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*
chemical_list: D016159:Tumor Suppressor Protein p53