title: Intercellular centrosome number is correlated with the copy number of chromosomes in bladder cancer.
abstract: Centrosome amplification, which may accelerate tumor progression through chromosomal instability, is frequently observed in human malignancies. The intercellular relation between the number of centrosomes and chromosomes, however, is poorly understood. Therefore, the relationship between centrosomes and chromosomal copy number in the same cells was investigated in bladder cancer. Centrosomes were evaluated by immunohistochemistry, using anti-gamma-tubulin antibody in eight bladder cancer cell lines. Fluorescence in situ hybridization with centromeric probes for chromosomes 7, 9, and 17 was then performed on the same cells stained with gamma-tubulin. The number of centrosomes was directly proportional to the number of chromosomes in cells with centrosome amplification, while a large intercellular variation in chromosomal copy number was detected in cells with normal numbers of centrosomes. Cancer cells with centrosome amplification of even centrosome numbers had significantly more even numbers of chromosomes. In cancer cells with four centrosomes, even numbers of chromosomes were detected more frequently (87.5%). These bladder cancer cell lines showed Aurora-A and p53 overexpression. These data indicate the occurrence of centrosome amplification with the possible mechanism of cytokinesis failure, resulting in a doubling of the number of centrosomes and chromosomes.
authors.affiliation: Department of Urology, Yamaguchi University School of Medicine, 1-1-1 Minami-kogushi, Ube, Yamaguchi 755-8505, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Eguchi
authors.forename: Akao
authors.initials: A
authors.lastname: Junpei
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nagao
authors.forename: Shigeru
authors.initials: S
authors.lastname: Sakano
authors.forename: Tomoko
authors.initials: T
authors.lastname: Furuya
authors.forename: Atsunori
authors.initials: A
authors.lastname: Oga
authors.forename: Shigeto
authors.initials: S
authors.lastname: Kawauchi
authors.forename: Kohsuke
authors.initials: K
authors.lastname: Sasaki
authors.forename: Hideyasu
authors.initials: H
authors.lastname: Matsuyama
mesh_terms: D045744:Cell Line, Tumor; D018385:Centrosome / Q000378:metabolism*; D002877:Chromosomes, Human / Q000235:genetics*; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics; D002899:Chromosomes, Human, Pair 9 / Q000235:genetics; D018628:Gene Dosage; D006801:Humans; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000473:pathology*