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- Hallor, Karolin H, et al.
(författare)
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Genomic profiling of chondrosarcoma: chromosomal patterns in central and peripheral tumors.
- 2009
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Ingår i: Clinical Cancer Research. - 1078-0432. ; 15:8, s. 2685-2694
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: Histologic grade is currently the best predictor of clinical course in chondrosarcoma patients. Grading suffers, however, from extensive interobserver variability and new objective markers are needed. Hence, we have investigated DNA copy numbers in chondrosarcomas with the purpose of identifying markers useful for prognosis and subclassification. EXPERIMENTAL DESIGN: The overall pattern of genomic imbalances was assessed in a series of 67 chondrosarcomas using array comparative genomic hybridization. Statistical analyses were applied to evaluate the significance of alterations detected in subgroups based on clinical data, morphology, grade, tumor size, and karyotypic features. Also, the global gene expression profiles were obtained in a subset of the tumors. RESULTS: Genomic imbalances, in most tumors affecting large regions of the genome, were found in 90% of the cases. Several apparently distinctive aberrations affecting conventional central and peripheral tumors, respectively, were identified. Although rare, recurrent amplifications were found at 8q24.21-q24.22 and 11q22.1-q22.3, and homozygous deletions of loci previously implicated in chondrosarcoma development affected the CDKN2A, EXT1, and EXT2 genes. The chromosomal imbalances in two distinct groups of predominantly near-haploid and near-triploid tumors, respectively, support the notion that polyploidization of an initially hyperhaploid/hypodiploid cell population is a common mechanism of chondrosarcoma progression. Increasing patient age as well as tumor grade were associated with adverse outcome, but no copy number imbalance affected metastasis development or tumor-associated death. CONCLUSION: Despite similarities in the overall genomic patterns, the present findings suggest that some regions are specifically altered in conventional central and peripheral tumors, respectively.
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| 2. |
- da Costa, Cristiana E. T., et al.
(författare)
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No Genomic Aberrations in Langerhans Cell Histiocytosis as Assessed by Diverse Molecular Technologies
- 2009
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 48:3, s. 239-249
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Tidskriftsartikel (refereegranskat)abstract
- The etiology of Langerhans cell histiocytosis (LCH), a disease characterized by uncontrolled proliferation of Langerhans cells, is unknown. Although some believe that LCH is reactive, others support a neoplastic origin. We tested the hypothesis that LCH is neoplastic by investigating potential consistent chromosomal aberrations in LCH cells. We used multiparameter DNA flow cytometry to analyze the DNA ploidy LCH cells in 20 cases, performed karyotype analysis in 31 cases, array-based comparative genomic hybridization (arrayCGH) and single nucleotide polymorphism (SNP) arrays with DNA from flow-sorted CD1a-positive and CD1a-negative cells in 19 cases. Ploidy analysis revealed diploid DNA content in all cases. The karyotype of all patients analyzed was normal, excluding the presence of balanced translocations. ArrayCGH and SNP arrays did not show genome abnormalities. Despite positive TP53 protein immunohistochemical staining, sequencing of exon 5 to 8 of p53 gene showed no alterations in 7 cases. This study strongly suggests that gross chromosomal abnormalities do not cause LCH. Although we cannot exclude cryptic point mutations in as yet unidentified genes, this study of 72 LCH cases shows that LCH may be the result of restricted oligoclonal stimulation rather than unlimited neoplastic proliferation. (c) 2008 Wiley-Liss, Inc.
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