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Sverre Heim - One of the best experts on this subject based on the ideXlab platform.
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runx1 pdcd6 fusion resultinG from a novel t 5 21 p15 q22 chromosome translocation in myelodysplastic syndrome secondary to chronic lymphocytic leukemia
PLOS ONE, 2018Co-Authors: Ioannis Panagopoulos, Francesca Micci, Sverre Heim, Ludmila Gorunova, Eva Marie Jacobsen, Kristin AndersenAbstract:Leukemic cells often carry chromosome aberrations which Generate chimeric Genes of pathoGenetic, diaGnostic, and proGnostic importance. New rearranGements GivinG rise to novel fusion Genes define hitherto unrecoGnized Genetic leukemia subGroups. G-bandinG, fluorescence in situ hybridization (FISH), and molecular Genetic analyses were done on bone marrow cells from a patient with chronic lymphocytic leukemia (CLL) and secondary myelodysplasia. The G-bandinG analysis revealed the karyotype 46,XX,del(21)(q22)[9]/46,XX[2]. FISH on metaphase spreads with a RUNX1 break apart probe demonstrated that part of RUNX1 (from 21q22) had moved to chromosome band 5p15. RNA sequencinG showed in-frame fusion of RUNX1 with PDCD6 (from 5p15), somethinG that was verified by RT-PCR toGether with SanGer sequencinG. Further FISH analyses with PDCD6 and RUNX1 home-made break apart/double fusion probes showed a red siGnal (PDCD6) on chromosome 5, a Green siGnal on chromosome 21 (RUNX1), and two yellow fusion siGnals, one on der(5) and the other on der(21). Reassessment of the G-bandinG preparations in liGht of the FISH and RNA-sequencinG data thus yielded the karyotype 46,XX,t(5;21)(p15;q22)[9]/46,XX[2]. The t(5;21)(p15;q22)/RUNX1-PDCD6 was detected only by performinG molecular studies of the leukemic cells, but should be souGht after also in other leukemic/myelodysplastic cases with del(21q).
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G bandinG and molecular cytoGenetic analyses of marGinal zone lymphoma
British Journal of Haematology, 2005Co-Authors: Hege Vangstein Aamot, Francesca Micci, Harald Holte, Jan Delabie, Sverre HeimAbstract:We analysed the acquired chromosomal aberrations of 22 marGinal zone lymphoma (MZL) patients by various Genome-wide cytoGenetic techniques, such as G-bandinG, multicolour fluorescence in situ hybridisation (M-FISH), cross-species colour bandinG (RxFISH), and comparative Genomic hybridisation (CGH), as well as FISH with locus-specific probes. Patients with an abnormal chromosome 3 (n = 11), the most frequently rearranGed chromosome, showed a shorter median survival than patients with a normal chromosome 3 (n = 11, 74 months vs. 219 months, P < 0.03). Four of five patients with nodal MZL had chromosome 3 abnormalities and patients with nodal MZL had a shorter median survival than patients in the other morpholoGical subGroups of MZL (P < 0.003). CGH analysis showed only Gains of chromosome material, namely of chromosome reGions 3p12-25, 3q12-21, 3q23-28, 12q13-15, 12q22-24, 19p13 and 19q13 in two to four cases each (20-40%). In two MZL, the novel unbalanced translocation der(13)t(3;13)(q24;p11) was detected as the sole karyotypic rearranGement, indicatinG that Gain of 3q24-qter could be an important event in the pathoGenesis of these lymphomas. Another two cases showed, in addition to other abnormalities, a t(4;14)(p13;q32). Both these lymphomas had involvement of the IGH Gene at 14q32, and one of them also of the RHOH/TTF Gene at 4p13, which encodes a new member of the RHO protein subfamily.
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characterization of supernumerary rinGs and Giant marker chromosomes in well differentiated lipomatous tumors by a combination of G bandinG cGh m fish and chromosome and locus specific fish
Cytogenetic and Genome Research, 2002Co-Authors: Francesca Micci, Manuel R Teixeira, Bodil Bjerkehagen, Sverre HeimAbstract:Supernumerary rinG chromosomes and/or Giant marker chromosomes are often seen in soft-tissue tumors of low-Grade or borderline maliGnancy, such as well-differentiated liposarcomas or atypical lipomas. Classic cytoGenetic bandinG techniques have proved insufficient to identify the Genomic composition and structure of such rinGs and markers, but fluorescent in situ hybridization (FISH) studies have shown that they consist mainly of amplified material from chromosome 12, more specifically from bands 12q13→q15. We have used the new FISH-based screeninG techniques comparative Genomic hybridization (CGH) and multicolor-FISH (M-FISH) in combination with G-bandinG and analysis by chromosome- and locus-specific fluorescent in situ probes to examine in detail the karyotypic characteristics of 22 lipomatous tumors, most of them classified histoloGically as well-differentiated liposarcomas, selected because they had been shown to harbor rinGs and/or marker chromosomes. M-FISH, in contrast to G- bandinG, was found to be informative with reGard to the chromosomal oriGin of the rinGs and other markers present, whereas CGH and hybridizations with locus-specific probes helped identify which subchromosomal reGions were involved. We found that chromosome bands 12q15→q21 were always Gained, with 12q15→q21 beinG amplified (i.e., a Green-to-red ratio >2 by CGH) in 14 of 22 tumors. In three tumors, two distinct but close amplicons in 12q could be identified, correspondinG to bands 12q13→q15 and 12q21. The Genomic seGment 1q21→q23 was Gained in 12 cases, reachinG the level of amplification in seven. Bands 6q24 and 7p15, whose pathoGenetic involvement in liposarcomas has not been reported previously, were Gained in three cases each. In addition, the rinGs and Giant markers often contained interspersed sequences from several other chromosomes that did not Give an equally clear impression of beinG nonrandomly involved.
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complete cytoGenetic characterization of the human breast cancer cell line ma11 combininG G bandinG comparative Genomic hybridization multicolor fluorescence in situ hybridization rxfish and chromosome specific paintinG
Cancer Genetics and Cytogenetics, 2001Co-Authors: Francesca Micci, Manuel R Teixeira, Sverre HeimAbstract:The MA11 cell line was established from maliGnant cells isolated from the bone marrow of a breast cancer patient. It metastasizes selectively to the brain in athymic mice. Since the Genomic rearranGements of only a few breast cancer cell lines have been characterized completely, we analyzed MA11 cytoGenetically. Because the G-bandinG analysis revealed a very complex karyotype with several markers and chromosomes with additional material of unknown oriGin, we used multicolor fluorescence in situ hybridization (M-FISH), cross-species color bandinG (RxFISH), comparative Genomic hybridization (CGH), and chromosome-specific probes to better characterize the chromosome abnormalities. The use of these FISH-based screeninG techniques allowed us to detect previously unsuspected chromosomal chanGes and determine the identity of chromosomal markers. Multicolor FISH was especially useful to identify the rearranGed chromosomes, whereas RxFISH, G-bandinG, and CGH were instrumental in determininG breakpoint positions, althouGh some uncertainties were removed only after hybridization with chromosome-specific probes. The combined analysis revealed a near-triploid karyotype with no less than 20 chromosomes demonstratinG structural rearranGements. The resultinG imbalances included several of those known to be common in primary breast carcinomas (Gain of 1q, 8q, and 20q and loss of 8p, 11q, and 13q), indicatinG that the MA11 cell line may serve as a Good model to study breast carcinoGenesis. The full cytoGenetic characterization we present may Guide future searches for the mechanism of orGan-selective metastasis in this model system and, possibly, also in vivo.
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characterization of chromosomal abnormalities in uroepithelial carcinomas by G bandinG spectral karyotypinG and fish analysis
International Journal of Cancer, 2001Co-Authors: Imad Fadlelmula, Soili Kytola, Yi Pan, Wengonn Lui, Gaetano Derienzo, Lars Forsberg, Nils Mandahl, Ludmila Gorunova, Ulf S R Bergerheim, Sverre HeimAbstract: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. (Less)
Francesca Micci - One of the best experts on this subject based on the ideXlab platform.
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runx1 pdcd6 fusion resultinG from a novel t 5 21 p15 q22 chromosome translocation in myelodysplastic syndrome secondary to chronic lymphocytic leukemia
PLOS ONE, 2018Co-Authors: Ioannis Panagopoulos, Francesca Micci, Sverre Heim, Ludmila Gorunova, Eva Marie Jacobsen, Kristin AndersenAbstract:Leukemic cells often carry chromosome aberrations which Generate chimeric Genes of pathoGenetic, diaGnostic, and proGnostic importance. New rearranGements GivinG rise to novel fusion Genes define hitherto unrecoGnized Genetic leukemia subGroups. G-bandinG, fluorescence in situ hybridization (FISH), and molecular Genetic analyses were done on bone marrow cells from a patient with chronic lymphocytic leukemia (CLL) and secondary myelodysplasia. The G-bandinG analysis revealed the karyotype 46,XX,del(21)(q22)[9]/46,XX[2]. FISH on metaphase spreads with a RUNX1 break apart probe demonstrated that part of RUNX1 (from 21q22) had moved to chromosome band 5p15. RNA sequencinG showed in-frame fusion of RUNX1 with PDCD6 (from 5p15), somethinG that was verified by RT-PCR toGether with SanGer sequencinG. Further FISH analyses with PDCD6 and RUNX1 home-made break apart/double fusion probes showed a red siGnal (PDCD6) on chromosome 5, a Green siGnal on chromosome 21 (RUNX1), and two yellow fusion siGnals, one on der(5) and the other on der(21). Reassessment of the G-bandinG preparations in liGht of the FISH and RNA-sequencinG data thus yielded the karyotype 46,XX,t(5;21)(p15;q22)[9]/46,XX[2]. The t(5;21)(p15;q22)/RUNX1-PDCD6 was detected only by performinG molecular studies of the leukemic cells, but should be souGht after also in other leukemic/myelodysplastic cases with del(21q).
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G bandinG and molecular cytoGenetic analyses of marGinal zone lymphoma
British Journal of Haematology, 2005Co-Authors: Hege Vangstein Aamot, Francesca Micci, Harald Holte, Jan Delabie, Sverre HeimAbstract:We analysed the acquired chromosomal aberrations of 22 marGinal zone lymphoma (MZL) patients by various Genome-wide cytoGenetic techniques, such as G-bandinG, multicolour fluorescence in situ hybridisation (M-FISH), cross-species colour bandinG (RxFISH), and comparative Genomic hybridisation (CGH), as well as FISH with locus-specific probes. Patients with an abnormal chromosome 3 (n = 11), the most frequently rearranGed chromosome, showed a shorter median survival than patients with a normal chromosome 3 (n = 11, 74 months vs. 219 months, P < 0.03). Four of five patients with nodal MZL had chromosome 3 abnormalities and patients with nodal MZL had a shorter median survival than patients in the other morpholoGical subGroups of MZL (P < 0.003). CGH analysis showed only Gains of chromosome material, namely of chromosome reGions 3p12-25, 3q12-21, 3q23-28, 12q13-15, 12q22-24, 19p13 and 19q13 in two to four cases each (20-40%). In two MZL, the novel unbalanced translocation der(13)t(3;13)(q24;p11) was detected as the sole karyotypic rearranGement, indicatinG that Gain of 3q24-qter could be an important event in the pathoGenesis of these lymphomas. Another two cases showed, in addition to other abnormalities, a t(4;14)(p13;q32). Both these lymphomas had involvement of the IGH Gene at 14q32, and one of them also of the RHOH/TTF Gene at 4p13, which encodes a new member of the RHO protein subfamily.
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characterization of supernumerary rinGs and Giant marker chromosomes in well differentiated lipomatous tumors by a combination of G bandinG cGh m fish and chromosome and locus specific fish
Cytogenetic and Genome Research, 2002Co-Authors: Francesca Micci, Manuel R Teixeira, Bodil Bjerkehagen, Sverre HeimAbstract:Supernumerary rinG chromosomes and/or Giant marker chromosomes are often seen in soft-tissue tumors of low-Grade or borderline maliGnancy, such as well-differentiated liposarcomas or atypical lipomas. Classic cytoGenetic bandinG techniques have proved insufficient to identify the Genomic composition and structure of such rinGs and markers, but fluorescent in situ hybridization (FISH) studies have shown that they consist mainly of amplified material from chromosome 12, more specifically from bands 12q13→q15. We have used the new FISH-based screeninG techniques comparative Genomic hybridization (CGH) and multicolor-FISH (M-FISH) in combination with G-bandinG and analysis by chromosome- and locus-specific fluorescent in situ probes to examine in detail the karyotypic characteristics of 22 lipomatous tumors, most of them classified histoloGically as well-differentiated liposarcomas, selected because they had been shown to harbor rinGs and/or marker chromosomes. M-FISH, in contrast to G- bandinG, was found to be informative with reGard to the chromosomal oriGin of the rinGs and other markers present, whereas CGH and hybridizations with locus-specific probes helped identify which subchromosomal reGions were involved. We found that chromosome bands 12q15→q21 were always Gained, with 12q15→q21 beinG amplified (i.e., a Green-to-red ratio >2 by CGH) in 14 of 22 tumors. In three tumors, two distinct but close amplicons in 12q could be identified, correspondinG to bands 12q13→q15 and 12q21. The Genomic seGment 1q21→q23 was Gained in 12 cases, reachinG the level of amplification in seven. Bands 6q24 and 7p15, whose pathoGenetic involvement in liposarcomas has not been reported previously, were Gained in three cases each. In addition, the rinGs and Giant markers often contained interspersed sequences from several other chromosomes that did not Give an equally clear impression of beinG nonrandomly involved.
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complete cytoGenetic characterization of the human breast cancer cell line ma11 combininG G bandinG comparative Genomic hybridization multicolor fluorescence in situ hybridization rxfish and chromosome specific paintinG
Cancer Genetics and Cytogenetics, 2001Co-Authors: Francesca Micci, Manuel R Teixeira, Sverre HeimAbstract:The MA11 cell line was established from maliGnant cells isolated from the bone marrow of a breast cancer patient. It metastasizes selectively to the brain in athymic mice. Since the Genomic rearranGements of only a few breast cancer cell lines have been characterized completely, we analyzed MA11 cytoGenetically. Because the G-bandinG analysis revealed a very complex karyotype with several markers and chromosomes with additional material of unknown oriGin, we used multicolor fluorescence in situ hybridization (M-FISH), cross-species color bandinG (RxFISH), comparative Genomic hybridization (CGH), and chromosome-specific probes to better characterize the chromosome abnormalities. The use of these FISH-based screeninG techniques allowed us to detect previously unsuspected chromosomal chanGes and determine the identity of chromosomal markers. Multicolor FISH was especially useful to identify the rearranGed chromosomes, whereas RxFISH, G-bandinG, and CGH were instrumental in determininG breakpoint positions, althouGh some uncertainties were removed only after hybridization with chromosome-specific probes. The combined analysis revealed a near-triploid karyotype with no less than 20 chromosomes demonstratinG structural rearranGements. The resultinG imbalances included several of those known to be common in primary breast carcinomas (Gain of 1q, 8q, and 20q and loss of 8p, 11q, and 13q), indicatinG that the MA11 cell line may serve as a Good model to study breast carcinoGenesis. The full cytoGenetic characterization we present may Guide future searches for the mechanism of orGan-selective metastasis in this model system and, possibly, also in vivo.
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detailed Genome wide screeninG for inter and intrachromosomal abnormalities by sequential G bandinG and rxfish color bandinG of the same metaphase cells
Cancer Genetics and Cytogenetics, 2000Co-Authors: Manuel R Teixeira, Francesca Micci, Claudia U Dietrich, Sverre HeimAbstract:While the now-classic chromosome bandinG methods, such as G-bandinG, remain the techniques of choice for the initial screeninG for karyotypic abnormalities, sometimes chromosomal rearranGements involve seGments too small or too similarly banded to be detected or described adequately by these techniques. The necessity to use a Genome-wide, fluorescence in situ hybridization (FISH)-based screeninG technique as a complement to G-bandinG is especially obvious in cases where the information obtained by the latter analysis does not provide an adequate Guide to the choice of probes for chromosome-specific FISH. Furthermore, the same metaphase cells should ideally be used for both G-bandinG and FISH analysis to overcome the scarcity of metaphases observed in many cases and to ensure the correct interpretation of chromosomal aberrations in cytoGenetically unstable neoplasms with massive cell-to-cell karyotypic variability. We describe a protocol which enables cross-species color bandinG (RxFISH), a new FISH-based screeninG technique that simultaneously imparts specific color bandinG patterns on all chromosomes, of preparations that have been G-banded and mounted for up to several years, as well as a procedure allowinG chromosome-specific paintinG of the same metaphase cells to resolve whatever doubts persist after the precedinG G-bandinG and RxFISH analyses. This approach makes possible a detailed, Genome-wide screeninG for inter- and intrachromosomal abnormalities includinG archival cases whose karyotypic rearranGements had been incompletely identified by G-bandinG.
Isabel Malheiro - One of the best experts on this subject based on the ideXlab platform.
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A 'G' chromosome bandinG study of three cupped oyster species: Crassostrea GiGas, Crassostrea anGulata and Crassostrea virGinica (Mollusca: Bivalvia)
Genetics Selection Evolution, 1999Co-Authors: Alexandra Leitão, Catherine Thiriot-quiévreux, Isabel MalheiroAbstract:The G-bandinG technique was performed on chromosomes from Gill tissue of three cupped oyster species: Orassostrea GiGas, Cmssostrea anGulata and Cmssostrea virGiniea. Identification of the ten individual chromosome pairs was obtained. Comparative analysis of G-banded karyotypes of the three species showed that their bandinG patterns Generally resembled each other, with chromosome pair 3 beinG similar in ail three species. However, differences from one species to another were also observed. The G-bandinG pattern hiGhliGhted Greater similarities between C. GiGas and C. anG'l!lata than between these two species and C. virGiniea, thus providinG an additional arGument for Genetic diverGence between these two evolutionary lineaGes. C. GiGas and C. anGulata showed a different G-bandinG patterns on the two arms of chromosome pair 7, which aGrees with their taxonomic separation. The application of this bandinG technique offers a new approach to specifie problems in oyster taxonorny and Genetics. © Inra/Elsevier, Paris chI'omosome / G-bandinG / Crassostrea GiGas / Crassostrea anGulata / Crassostrea virGinica
Manuel R Teixeira - One of the best experts on this subject based on the ideXlab platform.
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Genetic profilinG of colorectal cancer liver metastases by combined comparative Genomic hybridization and G bandinG analysis
Genes Chromosomes and Cancer, 2003Co-Authors: Chieu B Diep, Manuel R Teixeira, Luis Antonio Parada, Mette Eknaes, Jahn M Nesland, Bertil Johansson, Ragnhild A LotheAbstract:The majority of Genetic studies of colorectal carcinoGenesis have focused on chanGes found in primary tumors. Despite the fact that liver metastases are a leadinG cause of colorectal cancer deaths, the molecular Genetic basis of the advanced disease staGes remains poorly understood. We performed comparative Genomic hybridization (CGH) on 17 liver metastases from colorectal carcinomas and compared the quantitative profile with the qualitative profile previously obtained with chromosome bandinG. An averaGe of 12.6 aberrations per tumor was found by CGH. Chromosome 18 and chromosome arms 4q, 8p, and 17p were most frequently lost, whereas chromosomes 7 and 20 and chromosome arms 6p, 8q, and 13q were most frequently Gained. We compared the chromosome bandinG and CGH data after convertinG the karyotypes into net copy number Gains and losses. Ten tumors showed aGreement between the findinGs of the two techniques, whereas five tumors did not (in two cases, no mitotic cells were obtained for bandinG analysis). All five discordant cases had a “simple” abnormal or normal karyotype, but revealed multiple chanGes by CGH. A likely explanation for this discrepancy is that in vitro Growth before G-bandinG selected aGainst the cancer cells. InterestinGly, by comparinG the CGH profiles of the “complex” vs. the “simple”/normal karyotype Groups, deletion of 8p and Gain of 16q were seen more frequently in the former Group. The liver metastases had the same aberrations as seen in primary colorectal carcinomas, summarized in a literature survey. However, these aberrations were seen more frequently in liver metastases, which may be attributable to increased Genetic instability. © 2003 Wiley-Liss, Inc.
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characterization of supernumerary rinGs and Giant marker chromosomes in well differentiated lipomatous tumors by a combination of G bandinG cGh m fish and chromosome and locus specific fish
Cytogenetic and Genome Research, 2002Co-Authors: Francesca Micci, Manuel R Teixeira, Bodil Bjerkehagen, Sverre HeimAbstract:Supernumerary rinG chromosomes and/or Giant marker chromosomes are often seen in soft-tissue tumors of low-Grade or borderline maliGnancy, such as well-differentiated liposarcomas or atypical lipomas. Classic cytoGenetic bandinG techniques have proved insufficient to identify the Genomic composition and structure of such rinGs and markers, but fluorescent in situ hybridization (FISH) studies have shown that they consist mainly of amplified material from chromosome 12, more specifically from bands 12q13→q15. We have used the new FISH-based screeninG techniques comparative Genomic hybridization (CGH) and multicolor-FISH (M-FISH) in combination with G-bandinG and analysis by chromosome- and locus-specific fluorescent in situ probes to examine in detail the karyotypic characteristics of 22 lipomatous tumors, most of them classified histoloGically as well-differentiated liposarcomas, selected because they had been shown to harbor rinGs and/or marker chromosomes. M-FISH, in contrast to G- bandinG, was found to be informative with reGard to the chromosomal oriGin of the rinGs and other markers present, whereas CGH and hybridizations with locus-specific probes helped identify which subchromosomal reGions were involved. We found that chromosome bands 12q15→q21 were always Gained, with 12q15→q21 beinG amplified (i.e., a Green-to-red ratio >2 by CGH) in 14 of 22 tumors. In three tumors, two distinct but close amplicons in 12q could be identified, correspondinG to bands 12q13→q15 and 12q21. The Genomic seGment 1q21→q23 was Gained in 12 cases, reachinG the level of amplification in seven. Bands 6q24 and 7p15, whose pathoGenetic involvement in liposarcomas has not been reported previously, were Gained in three cases each. In addition, the rinGs and Giant markers often contained interspersed sequences from several other chromosomes that did not Give an equally clear impression of beinG nonrandomly involved.
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complete cytoGenetic characterization of the human breast cancer cell line ma11 combininG G bandinG comparative Genomic hybridization multicolor fluorescence in situ hybridization rxfish and chromosome specific paintinG
Cancer Genetics and Cytogenetics, 2001Co-Authors: Francesca Micci, Manuel R Teixeira, Sverre HeimAbstract:The MA11 cell line was established from maliGnant cells isolated from the bone marrow of a breast cancer patient. It metastasizes selectively to the brain in athymic mice. Since the Genomic rearranGements of only a few breast cancer cell lines have been characterized completely, we analyzed MA11 cytoGenetically. Because the G-bandinG analysis revealed a very complex karyotype with several markers and chromosomes with additional material of unknown oriGin, we used multicolor fluorescence in situ hybridization (M-FISH), cross-species color bandinG (RxFISH), comparative Genomic hybridization (CGH), and chromosome-specific probes to better characterize the chromosome abnormalities. The use of these FISH-based screeninG techniques allowed us to detect previously unsuspected chromosomal chanGes and determine the identity of chromosomal markers. Multicolor FISH was especially useful to identify the rearranGed chromosomes, whereas RxFISH, G-bandinG, and CGH were instrumental in determininG breakpoint positions, althouGh some uncertainties were removed only after hybridization with chromosome-specific probes. The combined analysis revealed a near-triploid karyotype with no less than 20 chromosomes demonstratinG structural rearranGements. The resultinG imbalances included several of those known to be common in primary breast carcinomas (Gain of 1q, 8q, and 20q and loss of 8p, 11q, and 13q), indicatinG that the MA11 cell line may serve as a Good model to study breast carcinoGenesis. The full cytoGenetic characterization we present may Guide future searches for the mechanism of orGan-selective metastasis in this model system and, possibly, also in vivo.
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detailed Genome wide screeninG for inter and intrachromosomal abnormalities by sequential G bandinG and rxfish color bandinG of the same metaphase cells
Cancer Genetics and Cytogenetics, 2000Co-Authors: Manuel R Teixeira, Francesca Micci, Claudia U Dietrich, Sverre HeimAbstract:While the now-classic chromosome bandinG methods, such as G-bandinG, remain the techniques of choice for the initial screeninG for karyotypic abnormalities, sometimes chromosomal rearranGements involve seGments too small or too similarly banded to be detected or described adequately by these techniques. The necessity to use a Genome-wide, fluorescence in situ hybridization (FISH)-based screeninG technique as a complement to G-bandinG is especially obvious in cases where the information obtained by the latter analysis does not provide an adequate Guide to the choice of probes for chromosome-specific FISH. Furthermore, the same metaphase cells should ideally be used for both G-bandinG and FISH analysis to overcome the scarcity of metaphases observed in many cases and to ensure the correct interpretation of chromosomal aberrations in cytoGenetically unstable neoplasms with massive cell-to-cell karyotypic variability. We describe a protocol which enables cross-species color bandinG (RxFISH), a new FISH-based screeninG technique that simultaneously imparts specific color bandinG patterns on all chromosomes, of preparations that have been G-banded and mounted for up to several years, as well as a procedure allowinG chromosome-specific paintinG of the same metaphase cells to resolve whatever doubts persist after the precedinG G-bandinG and RxFISH analyses. This approach makes possible a detailed, Genome-wide screeninG for inter- and intrachromosomal abnormalities includinG archival cases whose karyotypic rearranGements had been incompletely identified by G-bandinG.
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combined rxfish G bandinG allows refined karyotypinG of solid tumors
Human Genetics, 1999Co-Authors: Francesca Micci, Manuel R Teixeira, Claudia U Dietrich, Gunnar Saeter, Bodil Bjerkehagen, Sverre HeimAbstract:Chromosome bandinG analysis of solid tumors often yields incomplete karyotypes because of the complex rearranGements encountered. The addition of fluorescence in situ hybridization (FISH) methods has helped improve the accuracy of solid tumor cytoGenetics, but the absence of screeninG qualities from standard FISH approaches has proved a severe limitation. We describe the cytoGenetic analysis of ten solid tumors usinG G-bandinG followed by cross-species color bandinG (RxFISH), a FISH-based screeninG technique GivinG a chromosome-specific bandinG pattern based on the Genomic homoloGies between humans and Gibbons. The addition of RxFISH analysis in all cases led to the identification of previously unidentified intra- as well as interchromosomal rearranGements, thus GivinG a much more certain and detailed karyotype. In two Gastric stromal sarcomas, a tumor type for which no cytoGenetic data were hitherto available, numerical chromosomal aberrations dominated, but one of the tumors also carried an unbalanced 7;17-translocation with the same breakpoint in chromosome 17 as that seen in endometrial stromal sarcomas.
Alexandra Leitão - One of the best experts on this subject based on the ideXlab platform.
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A 'G' chromosome bandinG study of three cupped oyster species: Crassostrea GiGas, Crassostrea anGulata and Crassostrea virGinica (Mollusca: Bivalvia)
Genetics Selection Evolution, 1999Co-Authors: Alexandra Leitão, Catherine Thiriot-quiévreux, Isabel MalheiroAbstract:The G-bandinG technique was performed on chromosomes from Gill tissue of three cupped oyster species: Orassostrea GiGas, Cmssostrea anGulata and Cmssostrea virGiniea. Identification of the ten individual chromosome pairs was obtained. Comparative analysis of G-banded karyotypes of the three species showed that their bandinG patterns Generally resembled each other, with chromosome pair 3 beinG similar in ail three species. However, differences from one species to another were also observed. The G-bandinG pattern hiGhliGhted Greater similarities between C. GiGas and C. anG'l!lata than between these two species and C. virGiniea, thus providinG an additional arGument for Genetic diverGence between these two evolutionary lineaGes. C. GiGas and C. anGulata showed a different G-bandinG patterns on the two arms of chromosome pair 7, which aGrees with their taxonomic separation. The application of this bandinG technique offers a new approach to specifie problems in oyster taxonorny and Genetics. © Inra/Elsevier, Paris chI'omosome / G-bandinG / Crassostrea GiGas / Crassostrea anGulata / Crassostrea virGinica