Chromosomal aberrations in benign and malignant bilharzia-associated bladder lesions analyzed by comparative genomic hybridization.
BACKGROUND
Bilharzia-associated bladder cancer (BAC) is a major health problem in countries where urinary schistosomiasis is endemic. Characterization of the genetic alterations in this cancer might enhance our understanding of the pathogenic mechanisms of the disease but, in contrast to nonbilharzia bladder cancer, BAC has rarely been the object of such scrutiny. In the present study, we aimed to characterize chromosomal imbalances in benign and malignant post-bilharzial lesions, and to determine whether their unique etiology yields a distinct cytogenetic profile as compared to chemically induced bladder tumors.


METHODS
DNAs from 20 archival paraffin-embedded post-bilharzial bladder lesions (6 benign and 14 malignant) obtained from Sudanese patients (12 males and 8 females) with a history of urinary bilharziasis were investigated for chromosomal imbalances using comparative genomic hybridization (CGH). Subsequent FISH analysis with pericentromeric probes was performed on paraffin sections of the same cases to confirm the CGH results.


RESULTS
Seven of the 20 lesions (6 carcinomas and one granuloma) showed chromosomal imbalances varying from 1 to 6 changes. The most common chromosomal imbalances detected were losses of 1p21-31, 8p21-pter, and 9p and gain of 19p material, seen in three cases each, including the benign lesion.


CONCLUSIONS
Most of the detected imbalances have been repeatedly reported in non-bilharzial bladder carcinomas, suggesting that the cytogenetic profiles of chemical- and bilharzia-induced carcinomas are largely similar. However, loss of 9p seems to be more ubiquitous in BAC than in bladder cancer in industrialized countries.
Fadl-Elmula
Imad
I
Department of Clinical Genetics, University Hospital, SE-22185 Lund, Sweden. fadl_elmula@hotmail.com
Kytola
Soili
S
Leithy
Mona E L
ME
Abdel-Hameed
Mohamed
M
Mandahl
Nils
N
Elagib
Atif
A
Ibrahim
Muntaser
M
Larsson
Catharina
C
Heim
Sverre
S
D000818:Animals; D002869:Chromosome Aberrations; D004273:DNA, Neoplasm / Q000235:genetics; D005260:Female; D006099:Granuloma / Q000235:genetics* / Q000469:parasitology*; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods; D008297:Male; D009693:Nucleic Acid Hybridization / Q000379:methods; D016612:Paraffin Embedding / Q000379:methods; D012547:Schistosoma / Q000302:isolation & purification; D012552:Schistosomiasis / Q000235:genetics*; D001749:Urinary Bladder Neoplasms / Q000235:genetics* / Q000469:parasitology*; D014552:Urinary Tract Infections / Q000235:genetics / Q000469:parasitology
D004273:DNA, Neoplasm