RUNX1-MUTATED AML SHOW A HIGH FREQUENCY OF TRISOMY 8 AND TRISOMY 13 AND ARE ASSOCIATED WITH MUTATIONS IN ASXL1 AND COMPONENTS OF THE RNA-SPLICING MACHINERY
(Abstract release date: 05/19/16)
EHA Library. Stengel A. 06/09/16; 132433; E884
Disclosure(s): AS, MM: Employment by MLL Munich Leukemia Laboratory; KP: Employment by MLL2; WK, CH, TH: Equity ownership of MLL Munich Leukemia Laboratory
Dr. Anna Stengel
Contributions
Contributions
Abstract
Abstract: E884
Type: Eposter Presentation
Background
Mutations in RUNX1 have been reported in 5 to 20% of AML. A detailed cytogenetic and molecular genetic analysis of RUNX1-mutated AML has not been performed yet.
Aims
1. Comprehensive cytogenetic and molecular genetic characterization of AML with RUNX1 mutations. 2. Analysis of potential impact of the respective markers on prognosis.
Methods
The cohort comprised 140 cases of AML with RUNX1 mutations (95 male, 45 female). Median age was 67 years (range: 18-87 years). All patients were investigated using chromosome banding analysis (CBA). Mutation analyses by amplicon sequencing were performed for ASXL1, BCOR, CBL, CEBPA, DNMT3A, ETV6, EZH2, FLT3-ITD, FLT3-TKD, GATA2, IDH1, IDH2, KIT, KRAS, MLL-PTD, NPM, NRAS, SETBP1, SF3B1, SRSF2, TET2, TP53, U2AF1 and WT1. Variants of unknown significance were excluded from statistical analysis.
Results
CBA revealed a normal karyotype in 83/140 (59%) and an aberrant karyotype in 57/140 (41%) of patients: 37 (27%) cases harbored trisomies, 20 cases (14%) showed other aberrations. In more detail, +8 was detected in 17 cases (12%), followed by +13 (11 cases, 8%), +11 (4 cases, 3%) and +14 (4 cases, 3%). No other recurrent abnormalities were observed. A complex karyotype (>3 abnormalities) was not detected. The highest mutation frequency was observed for ASXL1 (42%), followed by SRSF2 (36%), BCOR (21%), FLT3-ITD (18%), TET2 (18%), IDH2 (17%) and U2AF1 (16%). Mutation frequencies >5% were also detected for DNMT3A (14%), MLL-PTD (14%), NRAS (13%), WT1 (12%), IDH1 (9%), SF3B1 (9%) and CEBPA (5%). Thus, mutations in genes coding for components of the RNA-splicing machinery were detected in 89 patients (64%). No CEBPA double mutations were identified. Totally, sequencing revealed 463 mutations in addition to RUNX1 (mean number of additional mutations per patient: 3). In detail, 3 patients (2%) showed no, 18 (13%) one, 44 (31%) two, 43 (31%) three, 22 (16%) four, 9 (6%) five and 1 (1%) six concomitant mutations. Thus, in 98% of patients at least one molecular mutation additional to RUNX1 was observed. Correlation analyses between cytogenetic and molecular genetic markers revealed a strong association of trisomies with mutations in splicing factor genes (spliceosome mutations in patients with vs. without trisomies: 33/37 (89%) vs. 55/103 (53%), p<0.001). Additionally, cases with +8 correlated with ASXL1 mutations (ASXL1mut in patients with vs. without +8: 11/17 (65%) vs. 45/122 (37%), p=0.036). An association was revealed for a normal karyotype (NK) with mutations in FLT3-ITD (with NK: 20/83 (24%) with FLT3-ITD; without NK: 5/57 (9%) with FLT3-ITD, p=0.024). In the total cohort, median overall survival (OS) was 29 months. An aberrant karyotype had no influence on OS. However, mutations in U2AF1 and NRAS both were associated with a significantly shorter OS (median OS, for U2AF1 mutated vs. unmutated, 21 vs. 33 months; p=0.039; for NRAS mutated vs. unmutated, 12 vs. 31 months, p=0.026) and in patients with ≥3 accompanying mutations (≥3 vs. <3 mutations, 20 vs. 57 months, p=0.002).
Conclusion
RUNX1-mutated AML show a NK or specific cytogenetic abnormalities (+8 or +13) and a lack of a complex karyotype. Moreover, they depict a typical pattern of additional molecular mutations with a high frequency of ASXL1 mutations and mutations in spliceosome genes (especially SRSF2 and U2AF1), which according to Lindsley et al. (Blood 2015) is specific for secondary AML. Further, no entity-defining genetic abnormalities were observed. Thus, RUNX1-mutated AML might qualify for a separate entity.
Session topic: E-poster
Keyword(s): AML, RUNX1
Type: Eposter Presentation
Background
Mutations in RUNX1 have been reported in 5 to 20% of AML. A detailed cytogenetic and molecular genetic analysis of RUNX1-mutated AML has not been performed yet.
Aims
1. Comprehensive cytogenetic and molecular genetic characterization of AML with RUNX1 mutations. 2. Analysis of potential impact of the respective markers on prognosis.
Methods
The cohort comprised 140 cases of AML with RUNX1 mutations (95 male, 45 female). Median age was 67 years (range: 18-87 years). All patients were investigated using chromosome banding analysis (CBA). Mutation analyses by amplicon sequencing were performed for ASXL1, BCOR, CBL, CEBPA, DNMT3A, ETV6, EZH2, FLT3-ITD, FLT3-TKD, GATA2, IDH1, IDH2, KIT, KRAS, MLL-PTD, NPM, NRAS, SETBP1, SF3B1, SRSF2, TET2, TP53, U2AF1 and WT1. Variants of unknown significance were excluded from statistical analysis.
Results
CBA revealed a normal karyotype in 83/140 (59%) and an aberrant karyotype in 57/140 (41%) of patients: 37 (27%) cases harbored trisomies, 20 cases (14%) showed other aberrations. In more detail, +8 was detected in 17 cases (12%), followed by +13 (11 cases, 8%), +11 (4 cases, 3%) and +14 (4 cases, 3%). No other recurrent abnormalities were observed. A complex karyotype (>3 abnormalities) was not detected. The highest mutation frequency was observed for ASXL1 (42%), followed by SRSF2 (36%), BCOR (21%), FLT3-ITD (18%), TET2 (18%), IDH2 (17%) and U2AF1 (16%). Mutation frequencies >5% were also detected for DNMT3A (14%), MLL-PTD (14%), NRAS (13%), WT1 (12%), IDH1 (9%), SF3B1 (9%) and CEBPA (5%). Thus, mutations in genes coding for components of the RNA-splicing machinery were detected in 89 patients (64%). No CEBPA double mutations were identified. Totally, sequencing revealed 463 mutations in addition to RUNX1 (mean number of additional mutations per patient: 3). In detail, 3 patients (2%) showed no, 18 (13%) one, 44 (31%) two, 43 (31%) three, 22 (16%) four, 9 (6%) five and 1 (1%) six concomitant mutations. Thus, in 98% of patients at least one molecular mutation additional to RUNX1 was observed. Correlation analyses between cytogenetic and molecular genetic markers revealed a strong association of trisomies with mutations in splicing factor genes (spliceosome mutations in patients with vs. without trisomies: 33/37 (89%) vs. 55/103 (53%), p<0.001). Additionally, cases with +8 correlated with ASXL1 mutations (ASXL1mut in patients with vs. without +8: 11/17 (65%) vs. 45/122 (37%), p=0.036). An association was revealed for a normal karyotype (NK) with mutations in FLT3-ITD (with NK: 20/83 (24%) with FLT3-ITD; without NK: 5/57 (9%) with FLT3-ITD, p=0.024). In the total cohort, median overall survival (OS) was 29 months. An aberrant karyotype had no influence on OS. However, mutations in U2AF1 and NRAS both were associated with a significantly shorter OS (median OS, for U2AF1 mutated vs. unmutated, 21 vs. 33 months; p=0.039; for NRAS mutated vs. unmutated, 12 vs. 31 months, p=0.026) and in patients with ≥3 accompanying mutations (≥3 vs. <3 mutations, 20 vs. 57 months, p=0.002).
Conclusion
RUNX1-mutated AML show a NK or specific cytogenetic abnormalities (+8 or +13) and a lack of a complex karyotype. Moreover, they depict a typical pattern of additional molecular mutations with a high frequency of ASXL1 mutations and mutations in spliceosome genes (especially SRSF2 and U2AF1), which according to Lindsley et al. (Blood 2015) is specific for secondary AML. Further, no entity-defining genetic abnormalities were observed. Thus, RUNX1-mutated AML might qualify for a separate entity.
Session topic: E-poster
Keyword(s): AML, RUNX1
Abstract: E884
Type: Eposter Presentation
Background
Mutations in RUNX1 have been reported in 5 to 20% of AML. A detailed cytogenetic and molecular genetic analysis of RUNX1-mutated AML has not been performed yet.
Aims
1. Comprehensive cytogenetic and molecular genetic characterization of AML with RUNX1 mutations. 2. Analysis of potential impact of the respective markers on prognosis.
Methods
The cohort comprised 140 cases of AML with RUNX1 mutations (95 male, 45 female). Median age was 67 years (range: 18-87 years). All patients were investigated using chromosome banding analysis (CBA). Mutation analyses by amplicon sequencing were performed for ASXL1, BCOR, CBL, CEBPA, DNMT3A, ETV6, EZH2, FLT3-ITD, FLT3-TKD, GATA2, IDH1, IDH2, KIT, KRAS, MLL-PTD, NPM, NRAS, SETBP1, SF3B1, SRSF2, TET2, TP53, U2AF1 and WT1. Variants of unknown significance were excluded from statistical analysis.
Results
CBA revealed a normal karyotype in 83/140 (59%) and an aberrant karyotype in 57/140 (41%) of patients: 37 (27%) cases harbored trisomies, 20 cases (14%) showed other aberrations. In more detail, +8 was detected in 17 cases (12%), followed by +13 (11 cases, 8%), +11 (4 cases, 3%) and +14 (4 cases, 3%). No other recurrent abnormalities were observed. A complex karyotype (>3 abnormalities) was not detected. The highest mutation frequency was observed for ASXL1 (42%), followed by SRSF2 (36%), BCOR (21%), FLT3-ITD (18%), TET2 (18%), IDH2 (17%) and U2AF1 (16%). Mutation frequencies >5% were also detected for DNMT3A (14%), MLL-PTD (14%), NRAS (13%), WT1 (12%), IDH1 (9%), SF3B1 (9%) and CEBPA (5%). Thus, mutations in genes coding for components of the RNA-splicing machinery were detected in 89 patients (64%). No CEBPA double mutations were identified. Totally, sequencing revealed 463 mutations in addition to RUNX1 (mean number of additional mutations per patient: 3). In detail, 3 patients (2%) showed no, 18 (13%) one, 44 (31%) two, 43 (31%) three, 22 (16%) four, 9 (6%) five and 1 (1%) six concomitant mutations. Thus, in 98% of patients at least one molecular mutation additional to RUNX1 was observed. Correlation analyses between cytogenetic and molecular genetic markers revealed a strong association of trisomies with mutations in splicing factor genes (spliceosome mutations in patients with vs. without trisomies: 33/37 (89%) vs. 55/103 (53%), p<0.001). Additionally, cases with +8 correlated with ASXL1 mutations (ASXL1mut in patients with vs. without +8: 11/17 (65%) vs. 45/122 (37%), p=0.036). An association was revealed for a normal karyotype (NK) with mutations in FLT3-ITD (with NK: 20/83 (24%) with FLT3-ITD; without NK: 5/57 (9%) with FLT3-ITD, p=0.024). In the total cohort, median overall survival (OS) was 29 months. An aberrant karyotype had no influence on OS. However, mutations in U2AF1 and NRAS both were associated with a significantly shorter OS (median OS, for U2AF1 mutated vs. unmutated, 21 vs. 33 months; p=0.039; for NRAS mutated vs. unmutated, 12 vs. 31 months, p=0.026) and in patients with ≥3 accompanying mutations (≥3 vs. <3 mutations, 20 vs. 57 months, p=0.002).
Conclusion
RUNX1-mutated AML show a NK or specific cytogenetic abnormalities (+8 or +13) and a lack of a complex karyotype. Moreover, they depict a typical pattern of additional molecular mutations with a high frequency of ASXL1 mutations and mutations in spliceosome genes (especially SRSF2 and U2AF1), which according to Lindsley et al. (Blood 2015) is specific for secondary AML. Further, no entity-defining genetic abnormalities were observed. Thus, RUNX1-mutated AML might qualify for a separate entity.
Session topic: E-poster
Keyword(s): AML, RUNX1
Type: Eposter Presentation
Background
Mutations in RUNX1 have been reported in 5 to 20% of AML. A detailed cytogenetic and molecular genetic analysis of RUNX1-mutated AML has not been performed yet.
Aims
1. Comprehensive cytogenetic and molecular genetic characterization of AML with RUNX1 mutations. 2. Analysis of potential impact of the respective markers on prognosis.
Methods
The cohort comprised 140 cases of AML with RUNX1 mutations (95 male, 45 female). Median age was 67 years (range: 18-87 years). All patients were investigated using chromosome banding analysis (CBA). Mutation analyses by amplicon sequencing were performed for ASXL1, BCOR, CBL, CEBPA, DNMT3A, ETV6, EZH2, FLT3-ITD, FLT3-TKD, GATA2, IDH1, IDH2, KIT, KRAS, MLL-PTD, NPM, NRAS, SETBP1, SF3B1, SRSF2, TET2, TP53, U2AF1 and WT1. Variants of unknown significance were excluded from statistical analysis.
Results
CBA revealed a normal karyotype in 83/140 (59%) and an aberrant karyotype in 57/140 (41%) of patients: 37 (27%) cases harbored trisomies, 20 cases (14%) showed other aberrations. In more detail, +8 was detected in 17 cases (12%), followed by +13 (11 cases, 8%), +11 (4 cases, 3%) and +14 (4 cases, 3%). No other recurrent abnormalities were observed. A complex karyotype (>3 abnormalities) was not detected. The highest mutation frequency was observed for ASXL1 (42%), followed by SRSF2 (36%), BCOR (21%), FLT3-ITD (18%), TET2 (18%), IDH2 (17%) and U2AF1 (16%). Mutation frequencies >5% were also detected for DNMT3A (14%), MLL-PTD (14%), NRAS (13%), WT1 (12%), IDH1 (9%), SF3B1 (9%) and CEBPA (5%). Thus, mutations in genes coding for components of the RNA-splicing machinery were detected in 89 patients (64%). No CEBPA double mutations were identified. Totally, sequencing revealed 463 mutations in addition to RUNX1 (mean number of additional mutations per patient: 3). In detail, 3 patients (2%) showed no, 18 (13%) one, 44 (31%) two, 43 (31%) three, 22 (16%) four, 9 (6%) five and 1 (1%) six concomitant mutations. Thus, in 98% of patients at least one molecular mutation additional to RUNX1 was observed. Correlation analyses between cytogenetic and molecular genetic markers revealed a strong association of trisomies with mutations in splicing factor genes (spliceosome mutations in patients with vs. without trisomies: 33/37 (89%) vs. 55/103 (53%), p<0.001). Additionally, cases with +8 correlated with ASXL1 mutations (ASXL1mut in patients with vs. without +8: 11/17 (65%) vs. 45/122 (37%), p=0.036). An association was revealed for a normal karyotype (NK) with mutations in FLT3-ITD (with NK: 20/83 (24%) with FLT3-ITD; without NK: 5/57 (9%) with FLT3-ITD, p=0.024). In the total cohort, median overall survival (OS) was 29 months. An aberrant karyotype had no influence on OS. However, mutations in U2AF1 and NRAS both were associated with a significantly shorter OS (median OS, for U2AF1 mutated vs. unmutated, 21 vs. 33 months; p=0.039; for NRAS mutated vs. unmutated, 12 vs. 31 months, p=0.026) and in patients with ≥3 accompanying mutations (≥3 vs. <3 mutations, 20 vs. 57 months, p=0.002).
Conclusion
RUNX1-mutated AML show a NK or specific cytogenetic abnormalities (+8 or +13) and a lack of a complex karyotype. Moreover, they depict a typical pattern of additional molecular mutations with a high frequency of ASXL1 mutations and mutations in spliceosome genes (especially SRSF2 and U2AF1), which according to Lindsley et al. (Blood 2015) is specific for secondary AML. Further, no entity-defining genetic abnormalities were observed. Thus, RUNX1-mutated AML might qualify for a separate entity.
Session topic: E-poster
Keyword(s): AML, RUNX1
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