Abstract
Prostate cancer and bladder cancer are common urological malignancies in
man, while a lack of basic information underlying the oncogenesis and the
tumor progression makes it difficult to form therapeutic strategies
against these malignancies. Recent advances of molecular biology revealed
that genetic alteration play a crucial role in the oncogenesis and
progression of these tumors.
Thus, deletions of chromosomes 8p (8p22 and 8p23-pter), lOq (lOq24-qter)
and 16q (16q22-qter) were studied on 53 cases of prostate cancer. In 42
patients with transitional cell carcinoma (TCC), chromosomal deletion at
17p (pS3) were investigated. The numerical aberrations of chromosomes 7,
9, 10 and 11 were studied in 37 TCC cases.
Forty-one (73%) cases with prostate cancer showed deletions of one or
more regions of 8p. The results were confirmed by those of Southern blot
study on 11 informative cases. A frequency of deletions of chromosome 8p
(LPL and D8S7) were significantly increased in proportion to
histopathological grade, while lOq (DlOS27) did not. As for chromosome
16q, the deletion of 16q (D16S155) was strongly associated with aberrant
expression of E-cadherin, histopathological grade and tumor metastasis. A
significantly higher frequency of progression was observed in patients
with LPL deletion than those without deletion. A Cox-Hazard multivariate
analysis revealed LPL deletion to be one of the significant prognostic
factors as well as stage and D8S7, while neither DlOS27, nor D 16S 155
showed any correlation to disease progression.
With regard to bladder cancer, 64% of specimens demonstrated p53 deletion
with significant correlation with grade (pThese results suggest that i)
non-random numerical aberrations might be early events of oncogenesis in
bladder cancer, and ii) specific chromosomal aberrations, such as 8p in
prostate cancer, or 17p deletion in bladder cancer, play a crucial role
in the development of tumor progression, hence of clinical value as a
diagnostic tool to predict the malignant potential and patient prognosis.
