Acceleration of chromosomal instability of BRCA1-associated hereditary breast cancers by p53 abnormality.
Chromosomal instability (CIN) of BRCA1-associated hereditary breast cancers was studied by fluorescence in situ hybridization of chromosomes 1, 11, and 17. CIN values (the percentage of cells with a nonmodal chromosome) were obtained for each of three chromosomes, and their average was finally used as the CIN value of the sample. BRCA1-associated tumors showed a significantly (p = 0.0089) higher CIN value than normal breast tissues (24.3 +/- 4.3, n = 7, vs. 9.2 +/- 1.1, n = 6, mean +/- SE). In addition, BRCA1-associated tumors with positive p53 immunostaining showed a significantly (p = 0.0018) higher CIN value than those with negative p53 immunostaining (35.7 +/- 3.5, n = 3, vs. 15.8 +/- 1.3, n = 4). These results demonstrate that a loss of BRCA1 function results in the growth of breast cancers with CIN, and this phenotype is further accelerated by p53 abnormality.
Miyoshi
Yasuo
Y
Department of Surgical Oncology, Osaka University Medical School, 2-2 Yamadaoka, Suita-shi, Osaka 565-0871, Japan.
Iwao
Kyoko
K
Ikeda
Noriko
N
Egawa
Chiyomi
C
Noguchi
Shinzaburo
S
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000737:chemistry / Q000235:genetics* / Q000473:pathology*; D002869:Chromosome Aberrations; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002880:Chromosomes, Human, Pair 11 / Q000235:genetics; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D005260:Female; D019398:Genes, BRCA1; D016158:Genes, p53; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
D018719:Erb-b2 Receptor Tyrosine Kinases; D016159:Tumor Suppressor Protein p53