Analysis of Chromosome 1p Abnormalities in Renal Oncocytomas by Loss of Heterozygosity Studies Correlation With Conventional Cytogenetics and Fluorescence In Situ Hybridization

Department of Pathology, Loyola University Medical Center, Maywood, IL 60153, USA.
American Journal of Clinical Pathology (Impact Factor: 2.51). 04/2008; 129(3):377-82. DOI: 10.1309/KC2465ANDWVAXYDM
Source: PubMed


We previously showed by cytogenetics and fluorescence in situ hybridization (FISH) that the most common chromosomal abnormality in renal oncocytomas is loss of chromosome 1 or 1p. In the present study, we evaluated chromosome 1 by loss of heterozygosity (LOH) studies. DNA was extracted from paraffin sections. Three microsatellite markers were used: D1S508, D1S199, and D1S2734. The regions targeted by FISH probes and LOH markers were close to each other but not overlapping. Among 16 tumors evaluated by all 3 techniques, in 2 cases, LOH could not be interpreted. LOH was detected in at least 1 locus in 12 (86%) of 14 renal oncocytomas studied, with other loci being noninformative or not interpretable (1 case). In 2 cases, the LOH results were inconclusive. These results provide further evidence to support widespread abnormalities in chromosome 1p in renal oncocytoma. Determining whether such abnormalities are unique to renal oncocytomas or are also present in other tumors requires further studies.

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    • "This may suggest that this is an early event in the histogenesis of both tumors, before additional cellular events lead to malignancy in lesions that progress to chRCC, similar to chromosome 3p loss in clear cell renal cell carcinoma, which is thought to be an early event in carcinogenesis. Loss of chromosome 1p has been identified recently in renal oncocytoma [20], but this has not been previously shown to be a common cytogenetic alteration common to both entities, which is the key insight. Our delineation of the nature of chromosome 1p loss in renal oncocytoma provides the opportunity to identify novel tumor suppressor genes in future studies, and in establishing a possible carcinogenesis progression sequence. "
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