[The relationships among DNA ploidy type determined by laser scanning cytometry, the overexpression of p53 protein and the numerical aberrations of chromosome 7 in bladder cancer].
The cellular DNA content of certain malignancies is regarded as a prognostic parameter. The mutant p53 is thought to destabilize centrosome replication, which leads to aberrant mitosis and chromosome instability. We investigated the relationship among DNA ploidy pattern type, numerical aberrations of chromosome 7 and p53 overexpression in 20 transitional cell carcinomas of the urinary bladder. The DNA ploidy pattern type was determined by laser scanning cytometry, while p53 overexpression was investigated immunohistochemically. Using fluorescence in situ hybridization with chromosome-specific probes, the copy number of chromosome 7 was counted by touch preparations of interphase nuclei. The cytometric analysis revealed that the DNA patterns were highly correlated with both the numerical aberrations of chromosome 7 (p = 0.0002) and the overexpression of p53. The incidences of p53 overexpression in DNA aneuploid tumors and DNA diploid ones were 78% and 10%, respectively (p = 0.0017). Our results suggest that the overexpression of abnormal p53 protein induces DNA aneuploidy in bladder cancer.
Department of Urology, Kanazawa Medical University.
K
K
Kawamura
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R
Ikeda
K
K
Suzuki
D000368:Aged; D000369:Aged, 80 and over; D002295:Carcinoma, Transitional Cell / Q000235:genetics* / Q000378:metabolism; D002869:Chromosome Aberrations; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics*; D004273:DNA, Neoplasm / Q000235:genetics*; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011003:Ploidies; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000378:metabolism
D004273:DNA, Neoplasm; D016159:Tumor Suppressor Protein p53