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- Adeyinka, Adewale, et al.
(författare)
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Comparative cytogenetic and DNA flow cytometric analysis of 242 primary breast carcinomas
- 2003
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Ingår i: Cancer Genetics and Cytogenetics. - 0165-4608. ; 147:1, s. 62-67
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Tidskriftsartikel (refereegranskat)abstract
- The cytogenetic and DNA flow cytometric findings in 242 breast carcinomas were compared. The combined use of both techniques improved the detection of abnormal cell populations from 65% by cytogenetic analysis alone and 59% by DNA flow cytometric analysis alone to 84%. Informative and comparable cytogenetic and flow cytometric data were obtained for 155 tumors. Among these 155 tumors, there was good concordance (64%) between the estimates of genomic changes by the two methods. Most discrepancies were among the DNA-diploid cases, where cytogenetic analysis detected small genomic changes. There were, however, also some exceptions in which large genomic changes detected by one method were missed by the other. Of the specific breast cancer-associated cytogenetic aberrations subjected to separate correlation analysis, polysomy for chromosome 20 was significantly associated with a high S-phase fraction, whereas loss of the long arm of chromosome 16 and/or the presence of a der(1;16) were significantly associated with a low S-phase fraction. Our data show that cytogenetic and DNA flow cytometric analyses of breast carcinomas give largely comparable results, and that combining data from both methods significantly improves the information obtained by either technique used alone on the genetic abnormalities in these tumors.
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| 2. |
- Bardi, G, et al.
(författare)
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Tumor karyotype predicts clinical outcome in colorectal cancer patients
- 2004
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Ingår i: Journal of Clinical Oncology. - 1527-7755. ; 22:13, s. 2623-2634
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Tidskriftsartikel (refereegranskat)abstract
- Purpose To investigate the prognostic value of the overall karyotypic features and specific chromosome aberrations in colorectal cancer (CRC). Patients and Methods Cytogenetic features of 150 primary CRCs investigated at the time of surgery were correlated with patient survival by univariate and multivariate analyses, using classical clinicopathologic parameters as covariates. Results In univariate analysis, in addition to tumor grade and clinical stage, structural aberrations as well as rearrangements of chromosomes 8 and 16 were significantly correlated with shorter overall survival. Karyotypic complexity, rearrangements of chromosomes 8 and 16, and loss of chromosome 4 were significantly correlated with shorter disease-free survival. In multivariate analysis, in addition to tumor grade, the type of chromosome aberrations (structural or numerical), ploidy, and loss of chromosome 18 came across as independent prognostic factors in the group of all patients. In the subset of patients with stage I and II carcinomas, none of the clinicopathologic variables could independently predict patient survival, whereas the presence of structural chromosomal aberrations was the only independent predictor of poor prognosis. In the subset of patients with stage III carcinomas, the presence of structural changes of chromosome 8 was a stronger independent predictor of prognosis than was tumor grade. Conclusion Cytogenetic tumor features are valuable predictors of prognosis in CRC patients. The tumor karyotype should therefore be taken into account in the clinical management of patients with this disease, especially for patients having cancers of the early or intermediate stages I, II, and III.
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| 3. |
- Elmula, Imad, et al.
(författare)
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Chromosomal aberrations in benign and malignant Bilharzia-associated bladder lesions analyzed by comparative genomic hybridization.
- 2002
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 2:5
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Tidskriftsartikel (refereegranskat)abstract
- 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. CONCLUSION: 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.
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| 4. |
- Fadl-Elmula, Imad, et al.
(författare)
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Characterization of chromosomal abnormalities in uroepithelial carcinomas by G-banding, spectral karyotyping and fish analysis
- 2001
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 92:6, s. 824-831
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Tidskriftsartikel (refereegranskat)abstract
- Chromosome analysis by G-banding, spectral karyotyping (SKY) and fluorescence in situ hybridization (FISH) was per formed on 24 short-term cultured transitional cell bladder carcinomas and 5 cell lines established from bladder carcinomas. Except for one tumor with an apparently normal chromosomal constitution, clonal chromosome abnormalities were detected in all examined cases by the combined approach. The application of SKY and FISH techniques improved the karyotypic descriptions, originally based on C-banding only, by identifying 32 additional numerical changes, by establishing the chromosomal origin of 27 markers and 2 ring chromosomes, by redefining 53 aberrations and by detecting 15 hidden chromosomal rearrangements. No recurrent translocation, however, was detected. The most prominent: karyotypic feature was thus the occurrence of deletions and losses of whole chromosome copies indicating the importance of tumor suppressor genes in transitional cell carcinoma pathogenesis. Invasive carcinomas were karyotypically more complex than were low grade superficial tumors. Specific leases of material from chromosome 9 and from chromosome arms I Ip and 8p, and gains of 8q and Iq seem to be early changes appearing in superficial tumors, whereas losses from 4p and 17p and the formation of an isochromosome for 5p were associated with more aggressive tumor phenotypes.
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| 5. |
- Höglund, Mattias, et al.
(författare)
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Identification of cytogenetic subgroups and karyotypic pathways in transitional cell carcinoma
- 2001
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Ingår i: Cancer Research. - 1538-7445. ; 61:22, s. 8241-8246
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Tidskriftsartikel (refereegranskat)abstract
- The clinical course in urinary bladder cancer is difficult or impossible to predict based on conventional disease parameters. It is a reasonable hypothesis that the genetic aberrations acquired by the tumor cells, being instrumental in bringing about the disease in the first place, may also hold the key to more reliable prognostication. However, though 200 transitional cell carcinomas (TCC), the most common bladder cancer in the Western world, with clonal chromosomal abnormalities have been reported, our knowledge about the karyotypic characteristics of these tumors remains insufficient. The aberration pattern is clearly nonrandom, but no completely specific primary or secondary karyotypic abnormality has been identified, and the chronological order in which the aberrations appear during disease progression is not well known. The high degree of karyotypic complexity in epithelial tumors like TCC is one reason why our picture of the sequential order of cytogenetic evolution is unclear. To overcome some of these difficulties we have used several statistical methods that allow analysis and interpretation of the relationship between cytogenetic aberrations in TCC. We show that there exists a temporal order with respect to the appearance of chromosomal imbalances and that this order is highly correlated with tumor stage and grade. Analyzing changes in the distribution of imbalances per tumor in G1, G2, and G3 tumors, we suggest that progression involves the acquisition of cytogenetically detectable and submicroscopic genetic changes at comparable frequencies. By means of computer simulations, we show that the imbalances -9, +7, and 1q+ appear earlier than expected from random events and that -6q, -5q, -18, +5p, -22p, and -15 appear later than expected. Using principal component analysis, we identify two cytogenetic pathways in TCC, one initiated by -9 and followed by -11p and 1q+, the other initiated by +7 and followed by 8p- and +8q. The -9 pathway was correlated with stage Ta-T2 tumors, whereas the +7 pathway was correlated with stage T1-T3 tumors, i.e., +7 tumors appeared to be more aggressive. Although these pathways are well separated at earlier stages, they later converge to contain a common set of imbalances.
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| 6. |
- Panagopoulos, Ioannis, et al.
(författare)
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Molecular genetic characterization of the EWS/CHN and RBP56/CHN fusion genes in extraskeletal myxoid chondrosarcoma.
- 2002
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257. ; 35:4, s. 340-352
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Tidskriftsartikel (refereegranskat)abstract
- Extraskeletal myxoid chondrosarcoma (EMC) is a soft-tissue neoplasm cytogenetically characterized by the translocations t(9;22)(q22;q11-12) or t(9;17)(q22;q11), generating EWS/CHN or RBP56/CHN fusion genes, respectively. In the present study, 18 EMCs were studied both cytogenetically and at the molecular level. Chromosomal aberrations were detected in 16 samples: 13 with involvement of 9q22 and 22q11-12, and three with rearrangements of 9q22 and 17q11. Fifteen cases had an EWS/CHN fusion transcript and three had an RBP56/CHN transcript. The most frequent EWS/CHN transcript (type 1; 10 tumors), involved fusion of EWS exon 12 with CHN exon 3, and the second most common (type 5; two cases) was fusion of EWS exon 13 with CHN exon 3. In all tumors with RBP56/CHN fusion, exon 6 of RBP56 was fused to exon 3 of CHN. By genomic XL PCR and sequence analyses, the breakpoints from 14 cases were mapped in the EWS, RBP56, and CHN genes. In CHN, 12 breakpoints were found in intron 2 and only two in intron 1. In EWS, the breaks occurred in introns 7 (one break), 12 (eight breaks), and 13 (one break), and in RBP56 in intron 6. Repetitive elements such as Alu and LINE sequences seem to have limited, if any, importance in the genesis of EWS/CHN and RBP56/CHN chimeras. Furthermore, there were no chi, chi-like, topoisomerase II, or translin consensus sequences in the introns harboring the translocation breakpoints, nor could the number of topo I sites in EWS, RBP56, and CHN introns explain the uneven distribution of the breakpoints among EWS or CHN introns. Additional genetic events, such as nucleotide insertions, homologies at the junction, deletions, duplications, and inversions, were found to accompany the translocations, indicating that the chromosomal translocations do not require sequence-specific recombinases or extensive homology between the recombined sequences. Copyright 2002 Wiley-Liss, Inc.
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