Genetic changes in uroepithelial tumors of patients with Balkan endemic nephropathy.

BACKGROUND

Balkan endemic nephropathy (BEN) is seen in certain regions of the Balkan Peninsula. The patients are predisposed to epithelial cell tumors of the urinary tract. These tumors have not been genetically investigated so far.

METHODS

We studied the loss of heterozygosity (LOH) in three BEN-associated tumors at seven microsatellite loci at 3q21.3 - 3q27.3. Comparative genomic hybridization (CGH) was also done and one of the tumors was investigated by 24-color FISH as well.

RESULTS

LOH in locus D3S1299 (3q24) was established in one case. CGH showed genetic gains at 1q, 3q, 7p, 7q, 15q, and 19q in at least two of the three tumors. Genetic loss was found in one case at 4q. Most frequent aberrations detected by 24-color FISH were der(X), der(X)t(X;18), der(16), der(3)t(3;15) and der(12).

CONCLUSION

The LOH suggests the presence of a new, so far unidentified tumor-suppressor gene at 3q24. In pTa BEN tumor CGH showed genome instability was extremely high. The 24-color FISH indicated highly complex chromosomal rearrangements. Chromosome 3 anomalies support our previous data on 3q24 - 3q26.3 association with BEN.