MOLECULAR CYTOGENETIC ANALYSIS OF COMPLEX KARYOTYPES IN PATIENTS WITH MDS AND AML.
(Abstract release date: 05/19/16)
EHA Library. Grebenyuk L. 06/09/16; 134530; PB1630
Ms. Lyuba Grebenyuk
Contributions
Contributions
Abstract
Abstract: PB1630
Type: Publication Only
Background
Cytogenetic findings at diagnosis are among the most important independent prognostic factors in patients with MDS and AML. Complex karyotype involving three or more chromosome abnormalities is associated with poor prognosis and disease progression. Precise identification of chromosome abnormalities in complex karyotype by conventional cytogenetic analysis (CCA) is limited due to low resolution of this method. Molecular cytogenetic techniques such as fluorescence in situ hybridization on interphase cells nuclei (FISH), multicolor fluorescence in situ hybridization on chromosomes (mFISH) and multicolor banding (mBAND) have significantly higher sensitivity and allow to identify complex chromosome abnormalities, marker chromosomes, submicroscopic deletions and specify chromosomes breakpoints.
Aims
The aim of our study is to characterize complex karyotypes in patients with MDS and AML using combination of molecular cytogenetic techniques.
Methods
Over a 2-year period CCA of bone marrow samples was performed in 234 patients with MDS and 83 patients with AML at diagnosis. Complex karyotypes were revealed in 20 patients (9 males and 11 females, median age 55 years), 11 patients with MDS (4.7%) and 9 patients with AML (10.8%). mFISH (24XCyte, MetaSystems) was performed in all 20 patients. Based on the results of CCA and mFISH we analyzed abnormal chromosomes using FISH with locus-specific and centromere DNA probes (LSI EGR1/D5S23, D5S721 Dual Color Probe Set in 12 cases, TP53/CEP 17 FISH Probe Kit in 10 cases, D7S522/CEP 7 FISH Probe Kit in 9 cases, CEP 8 SpectrumOrange DNA Probe Kit, ATM/CEP 11 FISH Probe Kit, LSI MLL Dual Color, Break Apart Rearrangement, D20S108 FISH Probe Kit, 1p36 Microdeletion Region Probe – LSI p58 (1p36)/TelVysion 1p/LSI 1q25 in each case one, ABBOTT), as well as mBAND probe (XCyte mBAND 5, XCyte mBAND 7, XCyte mBAND 15, XCyte mBAND 17, MetaSystems).
Results
CCA revealed an average of 4 karyotype abnormalities (from 3 to 14). Structural chromosome rearrangements were found in 20 cases: random translocations in 5 cases (25%), all of them were defined as simple reciprocal translocations, additional material of unknown origin in 12 cases (60%), marker chromosomes in 11 cases (55%). Non-random structural rearrangements were found in 3 patients: t(6;9) – 1, del5q31 -1 and del7q31 - 1 case. Most frequent numerical abnormalities were typical for MDS and AML trisomy 8 – 5 cases (25%), monosomy 5 - 8 (40%), 7 - 7 (35%) and 17 - 3 cases (15%). Molecular cytogenetic analysis revealed additional chromosome aberrations and/or additional chromosome breakpoints in 17 of 20 cases (85%). Translocations were found in 18 cases (90%): 9 (50%) – simple reciprocal translocations, 4 (22%) – complex translocations involving 3 chromosomes, 3 (16,5%) - complex translocations involving more than 3 chromosomes. In karyotype of 17 patients (85%) we found abnormalities of chromosomes 5 (60%), 7 (50%), 11 (20%) and 17 (45%). Except one case, chromosome breakpoints were identified in typical regions of known or potential genes: 5q31, 7q31, 11q23 and 17p13. Deletions 5q and 7q were confirmed in both cases. Monosomy 7 was confirmed in two of seven cases only. In all other cases with monosomy 5, 7, and 17 on the results of conventional analysis mFISH revealed fragments of these chromosomes involved in translocations. Based on the results of FISH all of these translocations, except one case, were combined by deletion of loci 5q31, 7q31 and 17p13. All marker chromosomes and chromosomes with additional material of unknown origin were recognized as complex translocations or derivative chromosomes with breakpoints in both arms.
Conclusion
In our study applying of molecular cytogenetic methods allowed to identify all numerical and structural abnormalities, unrecognized at CCA, clarify chromosome breakpoints and determine markers chromosomes origin. True monosomy 7 was confirmed in 10% only, and for chromosomes 5 and 17 true monosomy is not found. Combination of conventional and molecular cytogenetic techniques (FISH, mFISH and mBAND) is necessary for precise characteristic of complex karyotypes in MDS and AML and determination of exact breakpoints loci of potential oncogenes and tumor suppressor genes.
Session topic: E-poster
Keyword(s): AML, Complex aberrant karyotype, FISH, MDS
Type: Publication Only
Background
Cytogenetic findings at diagnosis are among the most important independent prognostic factors in patients with MDS and AML. Complex karyotype involving three or more chromosome abnormalities is associated with poor prognosis and disease progression. Precise identification of chromosome abnormalities in complex karyotype by conventional cytogenetic analysis (CCA) is limited due to low resolution of this method. Molecular cytogenetic techniques such as fluorescence in situ hybridization on interphase cells nuclei (FISH), multicolor fluorescence in situ hybridization on chromosomes (mFISH) and multicolor banding (mBAND) have significantly higher sensitivity and allow to identify complex chromosome abnormalities, marker chromosomes, submicroscopic deletions and specify chromosomes breakpoints.
Aims
The aim of our study is to characterize complex karyotypes in patients with MDS and AML using combination of molecular cytogenetic techniques.
Methods
Over a 2-year period CCA of bone marrow samples was performed in 234 patients with MDS and 83 patients with AML at diagnosis. Complex karyotypes were revealed in 20 patients (9 males and 11 females, median age 55 years), 11 patients with MDS (4.7%) and 9 patients with AML (10.8%). mFISH (24XCyte, MetaSystems) was performed in all 20 patients. Based on the results of CCA and mFISH we analyzed abnormal chromosomes using FISH with locus-specific and centromere DNA probes (LSI EGR1/D5S23, D5S721 Dual Color Probe Set in 12 cases, TP53/CEP 17 FISH Probe Kit in 10 cases, D7S522/CEP 7 FISH Probe Kit in 9 cases, CEP 8 SpectrumOrange DNA Probe Kit, ATM/CEP 11 FISH Probe Kit, LSI MLL Dual Color, Break Apart Rearrangement, D20S108 FISH Probe Kit, 1p36 Microdeletion Region Probe – LSI p58 (1p36)/TelVysion 1p/LSI 1q25 in each case one, ABBOTT), as well as mBAND probe (XCyte mBAND 5, XCyte mBAND 7, XCyte mBAND 15, XCyte mBAND 17, MetaSystems).
Results
CCA revealed an average of 4 karyotype abnormalities (from 3 to 14). Structural chromosome rearrangements were found in 20 cases: random translocations in 5 cases (25%), all of them were defined as simple reciprocal translocations, additional material of unknown origin in 12 cases (60%), marker chromosomes in 11 cases (55%). Non-random structural rearrangements were found in 3 patients: t(6;9) – 1, del5q31 -1 and del7q31 - 1 case. Most frequent numerical abnormalities were typical for MDS and AML trisomy 8 – 5 cases (25%), monosomy 5 - 8 (40%), 7 - 7 (35%) and 17 - 3 cases (15%). Molecular cytogenetic analysis revealed additional chromosome aberrations and/or additional chromosome breakpoints in 17 of 20 cases (85%). Translocations were found in 18 cases (90%): 9 (50%) – simple reciprocal translocations, 4 (22%) – complex translocations involving 3 chromosomes, 3 (16,5%) - complex translocations involving more than 3 chromosomes. In karyotype of 17 patients (85%) we found abnormalities of chromosomes 5 (60%), 7 (50%), 11 (20%) and 17 (45%). Except one case, chromosome breakpoints were identified in typical regions of known or potential genes: 5q31, 7q31, 11q23 and 17p13. Deletions 5q and 7q were confirmed in both cases. Monosomy 7 was confirmed in two of seven cases only. In all other cases with monosomy 5, 7, and 17 on the results of conventional analysis mFISH revealed fragments of these chromosomes involved in translocations. Based on the results of FISH all of these translocations, except one case, were combined by deletion of loci 5q31, 7q31 and 17p13. All marker chromosomes and chromosomes with additional material of unknown origin were recognized as complex translocations or derivative chromosomes with breakpoints in both arms.
Conclusion
In our study applying of molecular cytogenetic methods allowed to identify all numerical and structural abnormalities, unrecognized at CCA, clarify chromosome breakpoints and determine markers chromosomes origin. True monosomy 7 was confirmed in 10% only, and for chromosomes 5 and 17 true monosomy is not found. Combination of conventional and molecular cytogenetic techniques (FISH, mFISH and mBAND) is necessary for precise characteristic of complex karyotypes in MDS and AML and determination of exact breakpoints loci of potential oncogenes and tumor suppressor genes.
Session topic: E-poster
Keyword(s): AML, Complex aberrant karyotype, FISH, MDS
Abstract: PB1630
Type: Publication Only
Background
Cytogenetic findings at diagnosis are among the most important independent prognostic factors in patients with MDS and AML. Complex karyotype involving three or more chromosome abnormalities is associated with poor prognosis and disease progression. Precise identification of chromosome abnormalities in complex karyotype by conventional cytogenetic analysis (CCA) is limited due to low resolution of this method. Molecular cytogenetic techniques such as fluorescence in situ hybridization on interphase cells nuclei (FISH), multicolor fluorescence in situ hybridization on chromosomes (mFISH) and multicolor banding (mBAND) have significantly higher sensitivity and allow to identify complex chromosome abnormalities, marker chromosomes, submicroscopic deletions and specify chromosomes breakpoints.
Aims
The aim of our study is to characterize complex karyotypes in patients with MDS and AML using combination of molecular cytogenetic techniques.
Methods
Over a 2-year period CCA of bone marrow samples was performed in 234 patients with MDS and 83 patients with AML at diagnosis. Complex karyotypes were revealed in 20 patients (9 males and 11 females, median age 55 years), 11 patients with MDS (4.7%) and 9 patients with AML (10.8%). mFISH (24XCyte, MetaSystems) was performed in all 20 patients. Based on the results of CCA and mFISH we analyzed abnormal chromosomes using FISH with locus-specific and centromere DNA probes (LSI EGR1/D5S23, D5S721 Dual Color Probe Set in 12 cases, TP53/CEP 17 FISH Probe Kit in 10 cases, D7S522/CEP 7 FISH Probe Kit in 9 cases, CEP 8 SpectrumOrange DNA Probe Kit, ATM/CEP 11 FISH Probe Kit, LSI MLL Dual Color, Break Apart Rearrangement, D20S108 FISH Probe Kit, 1p36 Microdeletion Region Probe – LSI p58 (1p36)/TelVysion 1p/LSI 1q25 in each case one, ABBOTT), as well as mBAND probe (XCyte mBAND 5, XCyte mBAND 7, XCyte mBAND 15, XCyte mBAND 17, MetaSystems).
Results
CCA revealed an average of 4 karyotype abnormalities (from 3 to 14). Structural chromosome rearrangements were found in 20 cases: random translocations in 5 cases (25%), all of them were defined as simple reciprocal translocations, additional material of unknown origin in 12 cases (60%), marker chromosomes in 11 cases (55%). Non-random structural rearrangements were found in 3 patients: t(6;9) – 1, del5q31 -1 and del7q31 - 1 case. Most frequent numerical abnormalities were typical for MDS and AML trisomy 8 – 5 cases (25%), monosomy 5 - 8 (40%), 7 - 7 (35%) and 17 - 3 cases (15%). Molecular cytogenetic analysis revealed additional chromosome aberrations and/or additional chromosome breakpoints in 17 of 20 cases (85%). Translocations were found in 18 cases (90%): 9 (50%) – simple reciprocal translocations, 4 (22%) – complex translocations involving 3 chromosomes, 3 (16,5%) - complex translocations involving more than 3 chromosomes. In karyotype of 17 patients (85%) we found abnormalities of chromosomes 5 (60%), 7 (50%), 11 (20%) and 17 (45%). Except one case, chromosome breakpoints were identified in typical regions of known or potential genes: 5q31, 7q31, 11q23 and 17p13. Deletions 5q and 7q were confirmed in both cases. Monosomy 7 was confirmed in two of seven cases only. In all other cases with monosomy 5, 7, and 17 on the results of conventional analysis mFISH revealed fragments of these chromosomes involved in translocations. Based on the results of FISH all of these translocations, except one case, were combined by deletion of loci 5q31, 7q31 and 17p13. All marker chromosomes and chromosomes with additional material of unknown origin were recognized as complex translocations or derivative chromosomes with breakpoints in both arms.
Conclusion
In our study applying of molecular cytogenetic methods allowed to identify all numerical and structural abnormalities, unrecognized at CCA, clarify chromosome breakpoints and determine markers chromosomes origin. True monosomy 7 was confirmed in 10% only, and for chromosomes 5 and 17 true monosomy is not found. Combination of conventional and molecular cytogenetic techniques (FISH, mFISH and mBAND) is necessary for precise characteristic of complex karyotypes in MDS and AML and determination of exact breakpoints loci of potential oncogenes and tumor suppressor genes.
Session topic: E-poster
Keyword(s): AML, Complex aberrant karyotype, FISH, MDS
Type: Publication Only
Background
Cytogenetic findings at diagnosis are among the most important independent prognostic factors in patients with MDS and AML. Complex karyotype involving three or more chromosome abnormalities is associated with poor prognosis and disease progression. Precise identification of chromosome abnormalities in complex karyotype by conventional cytogenetic analysis (CCA) is limited due to low resolution of this method. Molecular cytogenetic techniques such as fluorescence in situ hybridization on interphase cells nuclei (FISH), multicolor fluorescence in situ hybridization on chromosomes (mFISH) and multicolor banding (mBAND) have significantly higher sensitivity and allow to identify complex chromosome abnormalities, marker chromosomes, submicroscopic deletions and specify chromosomes breakpoints.
Aims
The aim of our study is to characterize complex karyotypes in patients with MDS and AML using combination of molecular cytogenetic techniques.
Methods
Over a 2-year period CCA of bone marrow samples was performed in 234 patients with MDS and 83 patients with AML at diagnosis. Complex karyotypes were revealed in 20 patients (9 males and 11 females, median age 55 years), 11 patients with MDS (4.7%) and 9 patients with AML (10.8%). mFISH (24XCyte, MetaSystems) was performed in all 20 patients. Based on the results of CCA and mFISH we analyzed abnormal chromosomes using FISH with locus-specific and centromere DNA probes (LSI EGR1/D5S23, D5S721 Dual Color Probe Set in 12 cases, TP53/CEP 17 FISH Probe Kit in 10 cases, D7S522/CEP 7 FISH Probe Kit in 9 cases, CEP 8 SpectrumOrange DNA Probe Kit, ATM/CEP 11 FISH Probe Kit, LSI MLL Dual Color, Break Apart Rearrangement, D20S108 FISH Probe Kit, 1p36 Microdeletion Region Probe – LSI p58 (1p36)/TelVysion 1p/LSI 1q25 in each case one, ABBOTT), as well as mBAND probe (XCyte mBAND 5, XCyte mBAND 7, XCyte mBAND 15, XCyte mBAND 17, MetaSystems).
Results
CCA revealed an average of 4 karyotype abnormalities (from 3 to 14). Structural chromosome rearrangements were found in 20 cases: random translocations in 5 cases (25%), all of them were defined as simple reciprocal translocations, additional material of unknown origin in 12 cases (60%), marker chromosomes in 11 cases (55%). Non-random structural rearrangements were found in 3 patients: t(6;9) – 1, del5q31 -1 and del7q31 - 1 case. Most frequent numerical abnormalities were typical for MDS and AML trisomy 8 – 5 cases (25%), monosomy 5 - 8 (40%), 7 - 7 (35%) and 17 - 3 cases (15%). Molecular cytogenetic analysis revealed additional chromosome aberrations and/or additional chromosome breakpoints in 17 of 20 cases (85%). Translocations were found in 18 cases (90%): 9 (50%) – simple reciprocal translocations, 4 (22%) – complex translocations involving 3 chromosomes, 3 (16,5%) - complex translocations involving more than 3 chromosomes. In karyotype of 17 patients (85%) we found abnormalities of chromosomes 5 (60%), 7 (50%), 11 (20%) and 17 (45%). Except one case, chromosome breakpoints were identified in typical regions of known or potential genes: 5q31, 7q31, 11q23 and 17p13. Deletions 5q and 7q were confirmed in both cases. Monosomy 7 was confirmed in two of seven cases only. In all other cases with monosomy 5, 7, and 17 on the results of conventional analysis mFISH revealed fragments of these chromosomes involved in translocations. Based on the results of FISH all of these translocations, except one case, were combined by deletion of loci 5q31, 7q31 and 17p13. All marker chromosomes and chromosomes with additional material of unknown origin were recognized as complex translocations or derivative chromosomes with breakpoints in both arms.
Conclusion
In our study applying of molecular cytogenetic methods allowed to identify all numerical and structural abnormalities, unrecognized at CCA, clarify chromosome breakpoints and determine markers chromosomes origin. True monosomy 7 was confirmed in 10% only, and for chromosomes 5 and 17 true monosomy is not found. Combination of conventional and molecular cytogenetic techniques (FISH, mFISH and mBAND) is necessary for precise characteristic of complex karyotypes in MDS and AML and determination of exact breakpoints loci of potential oncogenes and tumor suppressor genes.
Session topic: E-poster
Keyword(s): AML, Complex aberrant karyotype, FISH, MDS
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