Characterization of MDS Harboring TET2 Mutations and/or TET2 Deletions

Background: TET2 mutations and deletions have been reported in MDS. A detailed analysis of the prognostic impact of TET2 deletions and their association to TET2 mutations is lacking. Aim: To characterize MDS with TET2 mutations (mut) and/or TET2 deletions (del) with respect to accompanying cytogenetic and molecular genetic abnormalities and their impact on prognosis. Patients and Methods: First 788 unselected MDS cases (cohort A) were evaluated. As in this cohort only 8 cases with TET2 deletion were detected, further MDS were screened for TET2 deletions. In total 77 MDS harboring a TET2 deletion were identified and included in cohort B. Both cohorts were analyzed by chromosome banding analysis, FISH, genomic arrays and mutation analysis of TET2. Cases from cohort A were also analyzed for mutations in ASXL1, ATM, BCOR, BRCC3, CBL, CTCF, DNMT3A, ETV6, EZH2, FBXW7, IDH1, IDH2, JAK2, KRAS, LAMB4, MPL, NCOR1, NCR2, NF1, NRAS, PHF6, PRPF8, PTPN11, RAD21, RUNX1, SETBP1, SF3B1, SMC3, SRSF2, STAG2, TET2, TP53, U2AF1 and ZRSR2. Results: In cohort A 248 cases (31%) with TET2mut were identified. TET2del and a normal karyotype were more frequent in MDS with TET2mut as compared to those with TET2 wild-type (wt) (3% vs 1%, p=0.006; 89% vs 78%, p<0.001). SF3B1 and ASXL1 were frequently mutated in both TET2mut and TET2wt MDS (32% and 34%, 22% and 18%, respectively). In MDS with TET2mut compared to MDS with TET2wt the following genes were less frequently mutated: ATM (0.5% vs 3%, p=0.05), DNMT3A (9% vs 15%, p=0.02), ETV6 (0.5% vs 3%, p=0.03), IDH1 (0.5% vs 3%, p=0.02), IDH2 (1% vs 5%, p=0.002), TP53 (2% vs 7%, p=0.004), U2AF1 (4% vs 9%, p=0.04), while the following genes were more frequently mutated: CBL (6% vs 2%, p=0.01), EZH2 (8% vs 2%, p<0.001), SRSF2 (27% vs 12%, p<0.001), and ZRSR2 (15% vs 3%, p<0.001). Overall spliceosome genes were more frequently mutated in TET2mut than in TET2wt MDS (77% vs 56%, p<0.001). In the total cohort A neither TET2mut nor TET2del had an impact on overall survival (OS). In TET2mut MDS and TET2wt MDS SF3B1mut were associated with favorable outcome, while TP53mut were associated with shorter OS in both subsets (table 1). However in TET2mut MDS mutations in RUNX1 (p<0.0001), CBL (p=0.001), and U2AF1 (p=0.03) were independently associated with shorter OS, while in TET2wt MDS mutations in KRAS (p=0.03), EZH2 (p=0.02), NRAS (p=0.02), SRSF2 (p=0.007), IDH2 (p=0.05), and ASXL1 (p=0.01) were independently associated with shorter OS. In cohort B 40/77 (52%) MDS with TET2del also harbored a TET2mut. The 4q deletion encompassing the TET2 gene was < 10 MB in size and thus cytogenetically cryptic in 77% of cases with TET2mut, while the TET2 deletion was cryptic in only 24% of cases without TET2mut. A normal karyotype was present in 37 cases (48%), a complex karyotype in 29 (38%) and other abnormalities in 11 cases (14%). TET2mut were frequent in cases with a normal karyotype (68% vs aberrant karyotype: 32%, p<0.001) and were rare in cases with a complex karyotype (13%). Relating the mutation load of TET2mut to the proportion of cells with TET2del as determined by FISH revealed in 60% of cases that both TET2 alterations were present in the main clone, while in 23% of cases the TET2mut was present in a subclone only and in 17% the TET2del was observed in a subclone only. In the subset of patients with TET2del in a subclone only, 83% showed a normal karyotype and none a complex karyotype, while in the subset of cases with TET2mut in a subclone only, 43% showed a normal and 29% a complex karyotype. In the total cohort B the presence of a TET2mut in addition to the TET2del had no prognostic impact, while the presence of a complex karyotype was associated with shorter OS (RR: 8.0, p=0.004). Conclusions: 1) TET2 deletions are rare in TET2 mutated MDS (3%). 2) TET2 mutations are frequent in MDS with TET2 deletion (52%). 3) TET2 mutations are highly correlated to a normal karyotype and are rare in complex karyotype. 3) Neither TET2 mutations nor TET2 deletions have a prognostic impact in MDS. 4) In TET2 mutated MDS mutations in RUNX1, TP53, CBL, and U2AF1 have the strongest negative independent impact on OS, which in TET2 wild-type MDS is the case for mutations in TP53, KRAS, EZH2, NRAS, SRSF2, IDH2 and ASXL1. Table The relative risk of parameters significantly (p<0.05) associated with overall survival are depicted in TET2 mutated and TET2 wild-type MDS Table. The relative risk of parameters significantly (p<0.05) associated with overall survival are depicted in TET2 mutated and TET2 wild-type MDS Disclosures Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Stengel:MLL Munich Leukemia Laboratory: Employment. Meggendorfer:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Impact of Expression of BAALC, CDKN1B, ERG, EVI1, and MN1 on Prognosis and Their Association with Karyotype, FLT3-ITD, NPM1 and MLL-PTD Status In Adult AML: A Comprehensive Study on 286 Cases

Blood ◽

10.1182/blood.v116.21.953.953 ◽

2010 ◽

Vol 116 (21) ◽

pp. 953-953

Author(s):

Claudia Haferlach ◽

Alexander Kohlmann ◽

Sonja Schindela ◽

Tamara Alpermann ◽

Wolfgang Kern ◽

...

Keyword(s):

Molecular Genetic ◽

Normal Karyotype ◽

Genetic Alterations ◽

Complex Karyotype ◽

Employment Equity ◽

Aberrant Expression ◽

Cox Regression Analysis ◽

Total Cohort ◽

Equity Ownership ◽

Low Expression

Abstract Abstract 953 Introduction: The WHO classification in 2008 listed for the first time aberrant expression of genes as molecular genetic alterations affecting outcome in AML. High expression of BAALC, ERG and MN1 were shown thus far to be associated with unfavorable outcome in normal karyotype AML (AML-NK). In addition high EVI1 expression was suggested to predict poor outcome. Recently, our group identified low expression of CDKN1B as a favorable prognostic marker. The aim of this study was to evaluate the expression of BAALC, CDKN1B, ERG, EVI1 and MN1 in AML comprising all cytogenetic risk groups with respect to their association with distinct cytogenetic and known molecular genetic subgroups and their impact on prognosis. Patients/Methods:: Expression levels of BAALC, CDKN1B, ERG, EVI1 and MN1 were determined by oligonucleotide microarrays (HG-U133 Plus 2.0, Affymetrix) in 286 AML (t(15;17) n=15; t(8;21) n=16; inv(16) n=7; normal karyotype n=99; 11q23/MLL-rearrangements n=10; complex karyotype n=51; other abnormalities n=88). Patients were further analyzed for mutations in NPM1, FLT3-ITD, CEPBA and MLL-PTD. Results: Expression of BAALC, CDKN1B, ERG, EVI1 and MN1 varied significantly between genetic subgroups: While t(15;17), t(8;21) and 11q23/MLL-rearrangements were associated with low CDKN1B expression, AML-NK and NPM+ cases showed a higher CDKN1B expression. Lower BAALC expression was observed in AML with t(15;17), 11q23/MLL-rearrangement and AML-NK as well as in FLT3-ITD+ AML and in NPM1+ AML, while in AML with other abnormalities a higher BAALC expression was observed. ERG expression was lower in AML with 11q23/MLL-rearrangement and normal karyotype, while it was higher in AML with complex karyotype. Low EVI1 expression was observed in AML with t(15;17), t(8;21), inv(16) and AML-NK, while it was higher in AML with 11q23/MLL-rearrangements. Low MN1 expression was associated with t(15;17), t(8;21) and AML-NK, while it was increased in cases with inv(16) or other abnormalities. Next, Cox regression analysis was performed with respect to overall survival (OS) and event free survival (EFS). In the total cohort high BAALC and ERG expression as continuous variables were associated with shorter OS and EFS while CDKN1B, EVI1 and MN1 had no impact. Furthermore the cohort was subdivided into quartiles of expression for each gene. After inspection of the survival curves the cut-off for high vs low expression was set as follows: BAALC: 75th percentile, CDKN1B: 25th percentile, ERG and MN1: 50th percentile. For EVI1 expression pts were separated into expressers (n=44) and non-expressers (n=242). Low CDKN1B expression was associated with longer OS and EFS in the total cohort (p=0.005, not reached (n.r.) vs 14.9 months (mo); p=0.013, 31 vs 9.7 mo). High BAALC expression had no impact on OS, but was associated with shorter EFS in the total cohort as well as in AML with intermediate cytogenetics and AML with other abnormalities (p=0.032, 6.2 vs 13.0 mo; p=0.027, 5.1 vs 11.3 mo; p=0.006, 2.3 vs 14.8 mo). High ERG expression was significantly associated with shorter OS and EFS in the total cohort (p=0.002, 12.5 mo vs n.r.; p=0.001, 8.1 vs 15.7 mo) as well as in AML-NK (p=0.001, 11.3 mo vs n.r.; p=0.010, 7.2 vs 22.1 mo). OS was also shorter in AML with unfavorable karyotype (p=0.048, median OS 9.3 mo vs n. r.). With respect to MN1 high expressers had a significantly shorter OS and EFS in the total cohort (p=0.004, 12.3 mo vs. n.r.; p=0.001, 8.1 vs 16.7 mo) as well as in AML-NK (p=0.001, 9.7 mo vs n.r.; p=0.001, 5.1 vs 22.1 mo). In a multivariate analysis including CDKN1B, ERG and MN1 all parameters retained their impact on OS as well as on EFS, while BAALC lost its impact on EFS. Adding MLL-PTD, NPM1+/FLT3-ITD-, favorable and unfavorable karyotype into the model demonstrated an independent significant adverse impact on OS for MLL-PTD (p=0.027, relative risk (RR): 2.38) and ERG expression (p=0.044, RR: 1.59) only. In the respective analysis for EFS only favorable karyotype showed an independent association (p=0.002, RR: 0.261). Conclusion: 1) Expression of BAALC, CDKN1B, ERG, EVI1 and MN1 varies significantly between cytogenetic subgroups. 2) BAALC as a continuous variable and CDKN1B, ERG and MN1 as dichotomized variables are independently predictive for OS and EFS in AML. 3) ERG expression even retains its independent prediction of shorter OS if cytogenetic and other molecular genetic markers are taken into account. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Schindela:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Comprehensive Genetic Analyses Of 213 PMF Patients Revealed 13% Of SRSF2 Mutations Being Strongly Correlated To ASXL1 Mutations

Blood ◽

10.1182/blood.v122.21.2828.2828 ◽

2013 ◽

Vol 122 (21) ◽

pp. 2828-2828

Author(s):

Manja Meggendorfer ◽

Tamara Alpermann ◽

Christiane Eder ◽

Claudia Haferlach ◽

Wolfgang Kern ◽

...

Keyword(s):

Molecular Marker ◽

Scoring System ◽

Sanger Sequencing ◽

Gene Mutations ◽

Normal Karyotype ◽

Prognostic Impact ◽

Wild Type ◽

Employment Equity ◽

Cytogenetic Aberrations ◽

Equity Ownership

Abstract Introduction Primary myelofibrosis (PMF) is a myeloproliferative neoplasm, characterized amongst others by stem-cell derived clonal myeloproliferation, bone marrow fibrosis, anemia, splenomegaly, constitutional symptoms and leukemic progression. Diagnosis is based in most cases on cytomorphology/histology demonstrating fibrosis as well as on mutations in JAK2 or MPL. The Dynamic Prognostic Scoring System (DIPSS)-plus is the current base for prognostication using different clinical parameters including karyotype. Furthermore, molecular genetic alterations are currently addressed to provide additional prognostic information. Recently, besides JAK2 and MPL further gene mutations have been described in a limited number of patients, including ASXL1 and SRSF2. Aim To analyze in a large cohort the frequency of SRSF2 and ASXL1 mutations in PMF patients, and to identify their prognostic impact in the context of other previously described gene mutations. Patients and Methods Diagnosis was done according to WHO classification. The cohort comprised 82 female and 131 male patients. In all cases a BCR-ABL rearrangement was excluded by RT-PCR or fluorescence in situ hybridization. JAK2V617F mutation was analyzed in all cases by melting curve analysis, MPLW515 mutation was subsequently analyzed in JAK2V617 wild type (wt) patients. In addition, we analyzed all patients for SRSF2 mutations by Sanger sequencing of the mutational hot spot region coding for amino acid Pro95. Cytogenetics was available in 139 patients. Patients were grouped in favorable (n=121) and unfavorable (n=18) karyotypes based on the DIPSS-plus-scoring system. Based on the previously described correlation of SRSF2mut with ASXL1mut and SETBP1mut in other myeloid entities, SRSF2 mutated cases were also analyzed for mutations in ASXL1 and SETBP1by Sanger sequencing. Follow-up data was available for 136 patients. Results 56% (120/213) of the patients showed JAK2V617F mutations and 18.0% (16/89) of JAK2wt patients carried a mutation in MPLW515 summing up to 65.1% of patients with an already established molecular marker. Of note, SRSF2 was mutated in 12.7% (27/213) of all PMF patients. Patients with SRSF2 mutation had higher white blood cell counts in comparison to SRSF2wt patients (20.00x109/L vs. 7.35x109/L; p=0.005), but there was no correlation to gender, age, hemoglobin level, platelet count or % of myeloblasts in the peripheral blood. In 17 SRSF2mut cases the karyotype was available, 12 were normal karyotype, while two cases showed an unfavorable karyotype according to DIPSS-plus with +8 and i(17)(q10), respectively. The remaining three aberrations belong to the favorable aberration group (del(20q), del(13q), and der(14)). There was no correlation of SRSF2 mutations to the cytogenetic subgroups normal karyotype (n=91) or DIPSS categories favorable and unfavorable aberrations. SRSF2 mutations were also equally distributed between both JAK2V617 or MPLW515 mutated and wild type cases. 18/27 SRSF2mut cases carried also either a JAK2 or MPL mutation, while 9 cases showed no additional JAK2 or MPL mutation. Therefore 30.6% patients remain that carry no mutation in at least one of the three genes investigated first. Interestingly, ASXL1 was frequently mutated in SRSF2 mutated patients (16/23 analyzed SRSF2mut patients) while none of the 24 analyzed SRSF2 mutated cases showed a mutation in SETBP1. To evaluate a potential influence of gene mutations on clinical outcome the overall survival (OS) was calculated. We could confirm that JAK2V617F had no prognostic impact. The same was true for MPLW515 mutations. In contrast to other studies we could not find any impact of SRSF2mutations on OS. Only cytogenetics, i.e. the normal karyotype showed a trend to a prognostic relevance: the median 3 year OS was 70.8% in patients with normal karyotype (n=56) but 58.8% in patients with cytogenetic aberrations (n=29; p=0.153). Conclusion 1) SRSF2 is mutated in 13% of PMF patients. 2) SRSF2 mutated patients show frequently an additional ASXL1 mutation but no coincidence with SETBP1. 3) The prognostic relevance of cytogenetic aberrations was confirmed, while the molecular marker SRSF2 shows no impact on prognosis. Disclosures: Meggendorfer: MLL Munich Leukemia Laboratory: Employment. Alpermann:MLL Munich Leukemia Laboratory: Employment. Eder:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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MDS and AML With ≥15% Ring Sideroblasts Share Overlapping Features In Cytogenetics But Demonstrate Different Patterns and Incidences Of SF3B1 mutations

Blood ◽

10.1182/blood.v122.21.2776.2776 ◽

2013 ◽

Vol 122 (21) ◽

pp. 2776-2776

Author(s):

Tamara Alpermann ◽

Sabine Jeromin ◽

Claudia Haferlach ◽

Wolfgang Kern ◽

Susanne Schnittger ◽

...

Keyword(s):

Amino Acid ◽

De Novo ◽

Normal Karyotype ◽

Amino Acid Position ◽

Prognostic Impact ◽

Mutation Load ◽

Employment Equity ◽

Total Cohort ◽

Ring Sideroblasts ◽

Equity Ownership

Abstract Background SF3B1 mutations (SF3B1mut) correlate with the presence of ring sideroblasts (RS) and can be found in MDS and in AML. Aim To evaluate the incidence of SF3B1mut in a large cohort of MDS and AML patients (pts) with ≥15% RS, and furthermore correlate to percentage of blasts, mutation load, concomitant genetic markers and to define their prognostic impact. Patients and Methods We investigated bone marrow (BM) in 1,238 newly diagnosed pts with MDS (n=770) and AML (n=468). In all cases MGG, MPO, NSE and iron staining was performed according to WHO criteria. 717 pts showed ≥15% RS and thus were included in this study. In all pts SF3B1mut and cytogenetic analysis was available. Results 579/717 (80.8%) pts were diagnosed with MDS (93.3% de novo; 6.7% therapy-related), and 138/717 (19.2%) with AML (61.6% de novo, 33.3% secondary, and 5.1% therapy-related). MDS subtypes were distributed as follows: 329 (56.8%) RCMD, 126 (21.8%) RARS, 63 (10.9%) RAEB-1, 55 (9.5%) RAEB-2, and 6 (1.0%) MDS with isolated del(5q). AML FAB subtypes were as follows: 11 (8.0%) M0; 10 (7.2%) M1; 70 (50.7%) M2, 14 (10.1%) M4, and 33 (23.9%) M6. Mean percentage of RS was 50.4% and differed between MDS and AML (52.9% vs 40.1%; p<0.001). Within the MDS cohort mean RS differed between the MDS WHO categories following an ascending order from MDS with isolated del(5q) (36.8%), RAEB-2 (40.0%), RAEB-1 (45.0%), RCMD (55.3%), to RARS (57.0%). In contrast, no differences were seen within the different AML FAB subtypes (mean RS M0: 40.3%, M1: 37.0%, M2: 40.1%, M6: 44.2%). Per definition, mean BM blasts differed between MDS and AML (3.6% vs 32.6%; p<0.001). Of note, percentages of RS and BM blasts were negatively correlated in the total cohort (p<0.001; r: -0.253) as well as for the cohort of MDS (p<0.001; r: -0.238) and showed a respective trend within the cohort of AML (p=0.072; r: -0.154). Within the cohort of MDS percentages of RS were higher in SF3B1mut vs wild-type (wt) pts (59.1% vs 42.3%; p<0.001) and mutation load of SF3B1mut (median 37.5%; range 10%-60%) correlated to the amount of RS (p<0.001, r: 0.258). No respective difference or correlation was seen within the AML cohort. Regarding cytogenetics SF3B1mut were more frequent in pts with normal karyotype than in pts with aberrant karyotype in the MDS cohort (76.1% vs 43.7%; p<0.001) as well as in the AML cohort (48.7% vs 18.2%; p=0.001). Further in the total cohort SF3B1mut were less frequent in ASXL1mut than in ASXL1wt (24.0% vs 48.5%; p=0.041), and within the AML cohort SF3B1mut showed a positive correlation to MLL-PTD (71.4% vs 25.7%; p=0.019). Additionally, we analyzed the position of the SF3B1mut. Within the total cohort 21 different amino acid positions were affected. We focused on the most frequent positions: 700 (55.9%), 666 (16.2%), 662 (8.0%), 625 (7.5%), 622 (4.0%), and 663 (1.7%). Mutations at position 666 were less frequent within MDS than in AML pts (14.3% vs 35.1%; p=0.003) and mutations at amino acid position 662 indicated a trend to be prevalent in MDS only (8.8% vs 0.0%; p=0.059). In addition, an analysis was performed for the contiguous subcohorts of 69 MDS with BM blasts between 10-19% and 44 AML with 20-29% (formerly RAEB-t). Neither differences in mean percentage of RS (38.7% vs 39.3%; n.s.), frequencies of SF3B1mut (17.4% vs 22.7%; n.s.), nor differences within the position of the mutation were identified. Follow-up data was available in 304 patients. Within the cohort of MDS SF3B1mut pts had better overall survival (OS) than SF3B1wt pts (5-year-survival rate 72.7% vs 35.2%; p<0.001). This holds true within the subcohort of normal karyotype (75.0% vs 35.6%; p=0.004) and within aberrant karyotype (67.6% vs 39.7%; p=0.012). No respective effect on OS was seen within the AML cohort. Also within the subgroup of early MDS (RCMD, RARS, and MDS with isolated del(5q); n=222) SF3B1mut pts had better OS than SF3B1wt pts (74.9% vs 48.2%; p<0.001), this holds true in patients with normal as well as in patients with aberrant karyotype (77.4% vs 56.1%; p=0.095 and 68.5% vs 44.6%; p=0.042, respectively). In contrast SF3B1 mutation status had no impact on OS within the cohort of MDS with excess of blasts (RAEB-1 and RAEB-2 together n=45). Conclusions 1) Percentages of RS are decreasing with increasing BM blasts percentages. 2) Different mutations within the SF3B1 gene are correlated to either MDS or AML. 3) The prognostic impact of SF3B1mut was only observed in patients with early MDS, but not in RAEB-1/2 or AML. Disclosures: Alpermann: MLL Munich Leukemia Laboratory: Employment. Jeromin:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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TP53 Mutations Are Present In 15.7% Of ALL, Are Especially Frequent In ALL With MYC-Rearrangement and In ALL With Low Hypodiploid Chromosome Status and Are Associated With Poor Prognosis

Blood ◽

10.1182/blood.v122.21.827.827 ◽

2013 ◽

Vol 122 (21) ◽

pp. 827-827

Author(s):

Claudia Haferlach ◽

Sandra Weissmann ◽

Sabrina Kuznia ◽

Susanne Schnittger ◽

Wolfgang Kern ◽

...

Keyword(s):

Mutation Frequency ◽

Tp53 Mutation ◽

Normal Karyotype ◽

Prognostic Impact ◽

Complex Karyotype ◽

Mutation Load ◽

Employment Equity ◽

Tp53 Mutations ◽

Equity Ownership ◽

B Lineage

Abstract Background TP53 is the most frequently mutated gene in cancer. The prognostic impact of TP53 mutations has been demonstrated in CLL, AML, and MDS. However, data on the frequency and prognostic impact of TP53 mutations in ALL is scarce. Aims We aimed at determining the TP53 mutation frequency, the association with cytogenetic subgroups and age, as well as the impact on survival. Patients and Methods In total, a large cohort of 625 patients with ALL was analyzed for TP53 mutations by deep-sequencing allowing to simultaneously quantify the mutation load. In all patients chromosome banding analyses have been performed. In addition, in 341 patients the copy number state of TP53 was determined by FISH. Results The cohort comprised 353 male and 272 female patients, median age was 49.5 years (range: 0.1-91.4 years). The cohort included the following groups: normal karyotype (n=101; 16.2%), t(9;22)(q34;q11) (n=162; 25.9%), MLL-translocations (n=37; 5.9%), MYC-translocations (n=40; 6.4%), t(12;21)(p13;q22) (n=15; 2.4%), low hypodiploidy (<40 chromosomes) (n=24; 3.8%), high hyperdiploidy (51-68 chromosomes) (n=38; 6.1%), complex karyotype (n=69; 11.0%), other cytogenetic abnormalities (n=139; 22.2%). Detailed data on immunophenotyping was available for 408 patients (T-lineage: n=105; B-lineage: n=267, Burkitt: n=36). In the total cohort, the frequency of TP53 mutations was 15.7% (98/625). TP53 mutations were most frequent in ALL with low hypodiploidy (22/24; 91.7%) and MYC-translocated ALL (25/40; 62.5%) and also quite frequent in ALL with complex karyotype (16/69; 23.2%), ALL with normal karyotype (13/101; 17.4%), and in MLL-translocated ALL (6/37; 16.2%). TP53 mutations were rare in t(9;22)(q34;q11) (7/162; 4.3%), high hyperdiploidy (3/38; 6.1%), and other cytogenetic abnormalities (6/139; 4.3%) and absent in ALL with t(12;21)(p13;q22) (0/15; 0%). Furthermore, TP53 mutations were less frequent in T-lineage ALL (8/105; 7.6%) as compared to B-lineage and Burkitt ALL (41/267; 15.4% and 21/36; 58.3%). TP53 mutation frequency increased with age (TP53mut <60 years vs ≥ 60 years 10.8% (45/417) vs 25.5% (53/208), p<0.0001). 25/64 (39.1%) TP53 mutated patients with available TP53 deletion status showed a deletion of the second allele, while in 17/319 (5.3%) TP53wt patients with available TP53 deletion status a TP53 deletion was detected (p<0.001). 11/98 (11.2%) TP53 mutated patients showed two TP53 mutations. Median overall survival (OS) was significantly shorter in TP53mut vs TP53wt patients (18.8 months vs 75.5 months, p<0.0001). OS at 4 years in patients <60 years was 80.1% in TP53wt compared to 56.8% in TP53mut (p=0.012) and 59.3% vs 22.6% in patients ≥ 60 years (p<0.0001). Also within the cytogenetic categories MYC-translocated and complex karyotype TP53 mutations had a significant adverse impact on overall survival. Further, patients with either two TP53 mutations or one TP53 mutation and an accompanying TP53 deletion had a significantly shorter OS as compared to patients with only one altered TP53 allele (median OS 11.5 vs 63.1 months, p=0.009). In contrast, OS in patients with a TP53 deletion without a TP53 mutation did not differ from patients without TP53 alterations. In addition, the TP53 mutation load was investigated by next-generation sequencing and varied between 2% and 98% (median: 41%). Within the subset of patients with TP53 mutation, patients with a mutation load >20% showed a significantly shorter OS as compared to patients with a lower mutation load (median OS 11.5 months vs not reached, p=0.003). Interestingly, OS in patients with a TP53 mutation load ≤ 20% did not differ from TP53wt patients. In multivariate Cox regression analysis including parameters significantly associated with shorter OS in univariate analysis the following factors retained an independent adverse impact on OS: age (<60 years vs ≥ 60 years, HR=2.2; p=0.01), MLL-translocation (HR=2.8; p=0.03), and TP53mut >20% (HR: 3.1, p=0.01). Conclusions 1. TP53 is mutated in 15.7% of ALL with the highest frequency in ALL with low hypodiploidy (91.7%) and MYC-translocated ALL (62.5%). 2. The TP53 mutation frequency increases with age. 3. TP53 mutations are associated with short survival independent of age and specific cytogenetic alterations. 4. TP53 mutations had a significant impact on OS only if the mutation load was >20%. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Weissmann:MLL Munich Leukemia Laboratory: Employment. Kuznia:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Landmark Analyses of DNMT3A Mutations in Hematological Malignancies

Blood ◽

10.1182/blood.v118.21.407.407 ◽

2011 ◽

Vol 118 (21) ◽

pp. 407-407

Author(s):

Vera Grossmann ◽

Alexander Kohlmann ◽

Claudia Haferlach ◽

Tamara Alpermann ◽

Melanie Wild ◽

...

Keyword(s):

Overall Survival ◽

Mutation Rate ◽

Mutation Frequency ◽

Cpg Methylation ◽

Homozygous Mutation ◽

Wild Type ◽

Employment Equity ◽

Acute Leukemias ◽

Equity Ownership

Abstract Abstract 407 CpG methylation is an epigenetic modification that is important for cellular development. The DNMT3A gene, located on chromosome 2p23.3, encodes for a DNA methyltransferase and plays a central role in de novo CpG methylation. Recently, DNMT3A has been reported to be mutated in 22% of AML and 8% of MDS (Ley et al., N Engl J Med, 2010; Walter et al., Leukemia, 2011). Further, DNMT3A mutations were observed to be associated with a short overall survival in both diseases, respectively. In order to determine the role of DNMT3A mutations in leukemia we investigated two different entities by next-generation sequencing: 145 AML patients and 83 cases harboring a T-cell acute lymphoblastic leukemia (T-ALL). We applied an amplicon based deep-sequencing assay (454 Life Sciences, Branford, CT) in combination with the 48.48 Access Array technology (Fluidigm, South San Francisco, CA). The peripheral blood or bone marrow samples were obtained from untreated patients. The AML cohort was restricted to cases with normal karyotype (CN-AML). 87/145 (60%) cases were specifically selected to be wild-type for NPM1, FLT3-ITD, CEBPA, and MLL-PTD, whereas 58/145 (40%) samples were mutated in NPM1 (n=33) or double-mutated in NPM1 and FLT3-ITD (n=25). In our cohort of AML cases without mutations in NPM1, FLT3-ITD, CEBPA, and MLL-PTD, we observed a DNMT3A mutation frequency of 17.2% (15/87 cases). The DNMT3A mutation rate in the NPM1 mutated/FLT3 wild-type cases (16/33, 48.5%, P=0.001) and NPM1/FLT3-ITD mutated cases (19/25, 76%, P<0.001) was significantly higher, confirming the association of DNMT3A mutations with NPM1 and FLT3-ITD mutations that had been reported previously (Ley et al.). Interestingly, also in the cohort of T-ALL we detected patients that carried a DNMT3A mutation (16/83, 19.3%), which is very similar to the mutation frequency in AML, and has not been described yet. To further address the biology of DNMT3A mutations in acute leukemias we combined the AML and T-ALL cohorts and identified in total 31 distinct missense mutations in 65 patients (49 AML, 16 T-ALL). Most frequently, amino acid R882 located in exon 23 was mutated (n=29 cases). In addition, we identified 7 frame-shift alterations, 5 nonsense and 2 splice-site mutations. Moreover, 9 of the 65 mutated cases had two independent mutations. Focusing on AML, only three (6.1%) of the 49 DNMT3A-mutated cases were observed to harbor two different mutations concomitantly. In contrast, in the cohort of T-ALL we detected two different mutations in 6/16 (37.5%, P=0.003) cases. Further, in the cohort of AML, no homozygous mutation was detected, however, in the T-ALL group, two cases harbored a homozygous mutation. Therefore, only 3/49 AML (6.1%) cases, but 8/16 T-ALL (50%) cases showed biallelic mutation status (P<0.001). With respect to overall survival, no association was seen in the complete cohort of CN-AML cases (n=145). After limiting this cohort to the cases without mutations in NPM1, FLT3-ITD, CEBPA and MLL-PTD (n=87), an inferior survival was observed for DNMT3A-mutated patients as compared to DNMT3A wild-type patients (n=15 vs. n=72; alive at 2 years: 27.9% vs. 56.6%; P=0.048). Remarkably, also in the cohort of T-ALL a worse survival for patients with DNMT3A mutations was seen which has not been reported thus far (n=13 vs. n=64; alive at 1 years: 28.6% vs. 80.9%; P=0.001). Subsequently, we were interested whether gain-of-function mutations of the DNMT3A gene were associated with trisomy 2 and acquired uniparental disomy (aUPDs) of the short arm of chromosome 2 where DNMT3A is located. As such, we investigated 9 cases harboring a trisomy 2 (AML n=4, MDS n=4, and CMML n=1) and one MDS patient harboring an aUPD 2p, as confirmed by SNP microarray analyses (SNP Array 6.0, Affymetrix, Santa Clara, CA). Not all, but 3/9 cases with trisomy 2 harbored a DNMT3A mutation (one AML, MDS, and CMML case each), suggesting that duplication of DNMT3A mutations can enhance the effect of the mutation. Moreover, the single case with aUPD 2p also showed a mutation, further suggesting that LOH leading to loss of the wild-type DNMT3A may be another mechanism of disease leading to progression of leukemia. In conclusion, we here report on a high mutation rate of DNMT3A in both AML and T-ALL and independently confirmed an inferior overall survival in these two entities, respectively. This indicates a significant role of DNMT3A alterations in myeloid as well as in lymphoid neoplasms. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Alpermann:MLL Munich Leukemia Laboratory: Employment. Wild:MLL Munich Leukemia Laboratory: Employment. Weissmann:MLL Munich Leukemia Laboratory: Employment. Eder:MLL Munich Leukemia Laboratory: Employment. Dicker:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Diagnostic and Prognostic Utility Of a 26-Gene Panel For Deep-Sequencing Mutation Analysis In Myeloid Malignancies

Blood ◽

10.1182/blood.v122.21.1547.1547 ◽

2013 ◽

Vol 122 (21) ◽

pp. 1547-1547 ◽

Cited By ~ 1

Author(s):

Alexander Kohlmann ◽

Sabrina Kuznia ◽

Niroshan Nadarajah ◽

Tamara Alpermann ◽

Sandra Weissmann ◽

...

Keyword(s):

Overall Survival ◽

Deep Sequencing ◽

Limit Of Detection ◽

Gene Panel ◽

Target Sequence ◽

Prognostic Impact ◽

Employment Equity ◽

Poor Overall Survival ◽

Myeloid Malignancies ◽

Equity Ownership

Abstract Introduction Molecular mutation analyses are performed in myeloid malignancies either in a stepwise procedure, i.e. one target gene after each other or are not performed at all, e.g. in low-risk MDS. A comprehensive pan-myeloid panel to simultaneously target mutations in 26 genes allows a comprehensive analysis with the perspective to detect disease defining mutations in the majority of patients. Aims To test the utility of a pan-myeloid panel in routine diagnostics. Methods We developed sensitive next-generation deep-sequencing (NGS) assays comprising in total 26 genes: ASXL1, BCOR, BRAF, CBL, DNMT3A, ETV6, EZH2, FLT3 (TKD), GATA1, GATA2, IDH1, IDH2, JAK2, KIT, KRAS, MPL, NPM1, NRAS, PHF6, RUNX1, SF3B1, SRSF2, TET2, TP53, U2AF1, and WT1. With the exception of RUNX1, which was sequenced on the 454 Life Sciences NGS platform (Branford, CT), all remainder genes were studied using a combination of a microdroplet-based assay (RainDance, Lexington, MA) and the MiSeq sequencing instrument (Illumina, San Diego, CA). The assay's turn-around time was less than 6 days, loading up to eight patients per sequencing run. In summary, 389 amplicons were designed with a median length of 206 bp (range 150-240 bp), representing a total target sequence of 78.15 kb. The sequencing library was constructed starting off 2.2 μg genomic DNA per patient, purified from isolated mononuclear cells. Using the 500 cycles sequencing-by-synthesis chemistry in median 7.644 millions of paired-end reads were generated per run. This resulted in a median coverage per gene of 7,626 reads (range 174-12,256). The lower limit of detection was set at a cut-off of 3%. Results Thus far, 191 prospectively collected cases have been analyzed during routine operations. In all cases the assay was successfully performed. Mutations (range 0-7) have been found in 119/191 (62.3%) cases. The major disease categories were as follows: MDS (n=76), suspected MDS (n=28), MDS/MPN (n=10), reactive bone marrow conditions (n=46), AML (n=8), CML (n=3), other conditions (n=20). We first were interested to address the utility of the panel in MDS when the analysis was restricted to the five prognostically relevant predictors of poor overall survival according to Bejar et al. (N Engl J Med. 2011;364:2496-506), i.e. ASXL1, ETV6, EZH2, RUNX1, and TP53. In detail, 69 cases with MDS were studied and in 42.0% (29/69) of cases mutations had been detected in these five genes while 40 patients showed no mutation. Interestingly, upon extending the analysis to the remainder 21 genes, at least one more mutation was discovered in 72.5% (29/40) of these cases, thereby extending the number of cases with at least one mutation to 84.1% (58/69) of patients. Of note, in 65.5% (19/29) of these latter cases, spliceosome mutations occurred in a mutually exclusive manner (SRSF2, SF3B1, U2AF1), thus also detecting mutations conferring a favorable clinical outcome, i.e. SF3B1 alterations. We next studied in more detail 28 cases with suspected MDS according to cytomorphology, i.e. cases with dysplastic features not sufficient to diagnose MDS. When again in a first step the five predictors of poor overall survival according to Bejar et al. were analyzed, mutations in ASXL1, ETV6, EZH2, RUNX1, and TP53 were observed in 25.0% of cases (7/28). In the group of 75.0% (21/28) of samples with no mutations according to Bejar et al., 28.6% (6/21) of cases harbored a mutation in the group of the 21 remainder genes analyzed simultaneously in the gene panel assay. Thus, in total the number of cases with at least one mutation increased to 46.4% (13/28) of patients. Of note, 6 of the 13 suspected MDS cases with mutations had a normal karyotype. In summary, with respect to correlations between these two cohorts, we observed that morphologically confirmed MDS cases (n=69) showed a higher number of mutated genes compared to “suspected MDS” cases (n=28) (1.88 vs 0.71; p<0.001). Conclusion A pan-myeloid screening assay using NGS allows to address 26 relevant gene mutations in myeloid malignancies with diagnostic or prognostic impact. This approach is scalable and adoptable to accommodate the inclusion of novel gene targets according to the latest evidence from the literature. Importantly, given the broad spectrum of mutations in myeloid diseases covered by such a panel, mutations can be identified in the majority of patients and enable to support a more comprehensive classification in these complex diseases. Disclosures: Kohlmann: MLL Munich Leukemia Laboratory: Employment. Kuznia:MLL Munich Leukemia Laboratory: Employment. Nadarajah:MLL Munich Leukemia Laboratory: Employment. Alpermann:MLL Munich Leukemia Laboratory: Employment. Weissmann:MLL Munich Leukemia Laboratory: Employment. Roller:MLL Munich Leukemia Laboratory: Employment. Albuquerque:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Gene Amplifications In 84 Patients With Acute Myeloid Leukemia and 31 Patients With Myelodysplastic Syndrome Investigated By Array CGH

Blood ◽

10.1182/blood.v122.21.3724.3724 ◽

2013 ◽

Vol 122 (21) ◽

pp. 3724-3724

Author(s):

Andreas Roller ◽

Simone Weber ◽

Alexander Kohlmann ◽

Melanie Zenger ◽

Marita Staller ◽

...

Keyword(s):

Array Cgh ◽

Chromosomal Abnormalities ◽

Ring Chromosome ◽

Normal Karyotype ◽

Structural Type ◽

Single Copy ◽

Chromosome 8 ◽

Complex Karyotype ◽

Employment Equity ◽

Equity Ownership

Abstract Background Gains and losses of chromosomal material are frequent in AML and MDS and usually lead to loss or gain of a single copy of a whole chromosome, a chromosome arm or small stretches of the chromosome that may be microscopically invisible. More rarely, amplifications of chromosomal regions (defined as the presence of more than 6 copies of a region per cell) are observed. These supernumerary copies are located either extrachromosomally as small acentric chromosomal structures - so called double-minutes (dmin) - or intrachromosomally as large contiguous stretches of amplified DNA, so called homogeneously staining regions (HSR). Aims Characterize AML and MDS cases with gene amplifications with respect to size, affected genes and accompanying chromosomal abnormalities as well as TP53 status. Patients and Methods 84 AML and 31 MDS cases with cytogenetically visible amplifications were selected for this study. All cases were analyzed by array CGH, chromosome banding analysis, sequencing for TP53 mutations as well as FISH for TP53 deletions. Results The cohort comprised 55 (47.8%) males and 60 (52.2%) females with a median age of 72.0 years (range 38.0 - 90.3 years). A complex karyotype (≥4 aberrations) was present in 92/115 (80.0%) cases (AML=65/84 (77.4%); MDS=27/31 (87.1%)). In total, 385 amplified regions were identified by array CGH. In more detail: 3q26 (AML: n=6; MDS: n=3), 8q24 (AML: n=15; MDS: n=1), 11q21-25 (AML: n=42; MDS: n=13), 13q12 (AML: n=3; MDS: n=1), 13q31 (AML: n=3; MDS: n=2), 19p13 (AML: n=2; MDS: n=4), and 21q21-q22 (AML: n=24; MDS: n=5). The median number of amplified regions was 3 (range 1-18). In 14/115 (12.2%) cases, the amplification was located in dmins (AML: n=11; MDS: n=3) and in 101/115 (87.8%) patients in HSR (AML: n=73; MDS: n=28). In 40 of the latter 101 cases (39.6%) (AML: n=24; MDS: n=16) the amplification was located on a ring chromosome (rc). In patients with complex karyotypes we detected a significantly higher number of amplified regions as compared to non-complex karyotypes (3.5 vs. 2.8; p=0.015). No association between the complexity of the karyotype and the structural type of the amplification (dmin vs rc) was observed. Cases with non-complex karyotypes frequently harbored a 5q deletion (6/23; 26.1%) or chromosome 8 abnormalities (3/23; 13.0%). Within the subgroup of non-complex karyotypes del(5q) cases showed a tendency to a higher number of amplified regions (3.6 vs. 1.9; p=0.140). Further, amplifications of 11q genes were more frequent in complex karyotypes (54.4% vs. 21.7%; p=0.005), whereas 8q amplifications were more frequent in non-complex karyotypes (43.5% vs. 4.4%; p<0.001). We detected a large region on band 11q24, which was amplified in 41/53 (77.4%) cases. This commonly amplified region contains 1,575 genes including the MLL gene. Cases harboring dmins had shorter amplified regions compared to cases with rc (4,428,112.5 bp vs. 18,265,496.9 bp; p=0.028). Moreover, we detected a positive correlation of patients having a rc and gene amplification on chromosome 11q23-25 (p<0.05). On chromosome 3q, 8/9 (88.9%) cases shared a minimal amplified region covering the EVI1 gene. In comparison to samples obtained from healthy donors (n=47), the EVI1 expression was significantly higher in cases with EVI1 amplification (87.4 vs. 0.5; p=0.048). On chromosome 21q the regions of amplifications were heterogeneous. However, we detected a minimal region containing 11 genes including ERG which was amplified in 26/29 (89.7%) patients. ERG expression data was available in 8 cases and was significantly higher compared to a control cohort of AML with normal karyotype (n=331) (729.2 vs. 229.0; p=0.05). On chromosome 8 an amplified region was identified in 15/16 cases. In 14 of these cases (87.5%) the region included MYC. TP53mut were present in 93/115 (80.9%) patients, accompanied by a TP53del in 28/93 (30.1%) cases. Interestingly, cases harboring a TP53mut had more amplified regions compared to TP53wt (3.4 vs. 1.7; p<0.001). Conclusions 1. MLL is the most frequently amplified gene in AML and MDS. 2. Patients with complex karyotypes or TP53mut harbored more amplified regions compared to patients with non-complex karyotypes and TP53wt. 3. Amplifications on 11q were more frequent in complex karyotype whereas gene amplifications on 8q were predominantly observed in non-complex karyotypes. 4. EVI1 and ERG gene amplifications lead to a higher expression of the respective genes. Disclosures: Roller: MLL Munich Leukemia Laboratory: Employment. Weber:MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Zenger:MLL Munich Leukemia Laboratory: Employment. Staller:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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In CLL with Normal Karyotype By Conventional and Genomic Array Karyotyping the Prognostic Impact of an Unmutated IGHV Status Is Stronger Than the Impact of Gene Mutations

Blood ◽

10.1182/blood.v128.22.4357.4357 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4357-4357 ◽

Cited By ~ 1

Author(s):

Calogero Vetro ◽

Torsten Haferlach ◽

Manja Meggendorfer ◽

Sabine Jeromin ◽

Constance Regina Baer ◽

...

Keyword(s):

Gene Mutation ◽

Mutation Rate ◽

Gene Mutations ◽

Normal Karyotype ◽

Prognostic Impact ◽

Employment Equity ◽

Mutation Status ◽

Genomic Array ◽

Equity Ownership ◽

The Impact

Abstract Background: In 15-20% of CLL cases no aberrations are detected by chromosome banding analysis (CBA) and FISH due to limited resolution, lack of evaluable metaphases or presence of aberrations in loci not covered by standard-panel FISH probes. As reported in our previous study (Haferlach C. et al., ASH 2015, abs ID#79545), genomic arrays (GA) detected abnormalities in almost 20% of cases classified as normal by CBA and FISH and these showed an impact on time to first treatment (TTT) (Vetro C. et al., EHA 2016, abs ID# E1069). The CLL subgroup without abnormalities in CBA, FISH, and GA has not been characterised in detail, so far. Aims: 1) to describe CLL without abnormalities by CBA/FISH/GA by evaluating an extended gene panel, the IGHV mutation status and the B-cell receptor (BCR) stereotypy; 2) to determine prognostic impact of these factors. Patients and Methods: CLL diagnosis was based on cytomorphology and immunophenotyping according to standard guidelines. From a cohort of 1190 patients at diagnosis, 133 (11%) were selected based on normal karyotype by CBA, no abnormalities by interphase FISH with probes for 17p13 (TP53), 13q14 (D13S25, D13S319, DLEU), 11q22 (ATM), centromeric region of chromosome 12 and t(11;14)(q13;q32) (IGH-CCND1) and no abnormalities by GA (SurePrint G3 ISCA CGH+SNP Microarray, Agilent, Waldbronn, Germany). IGHV mutation status and BCR stereotypy were determined according to Agathangelidis et al., Blood 2012, and DNA sequencing was performed for the following genes: ATM; SF3B1; TP53; KLHL6; KRAS; MYD88; NOTCH1; NRAS; POT1; FBXW7; HIST1H1E; XPO1; ITPKB; MAPK1; BIRC3; BRAF; DDX3X; EGR2; RIPK1; RPS15; CND2. Results: Median age was 66 years (range: 33-83). Median follow-up was 5.6 years, 33 patients (25%) received treatment since genetic analyses. 10-year overall survival (OS) was 76% and median TTT was 9.2 years. Mutations were observed in 53 patients (40%): SF3B1 (n=17; 13%); NOTCH1 (n=10; 8%); KLHL6 (n=6; 5%); TP53 (n=6; 5%); ATM (n=5; 4%); XPO1 (n=4; 3%); FBXW7 (n=3; 2%); MYD88 (n=3; 2%); DDX3X (n=2; 2%); POT1 (n=2; 1.5%); ITPKB (n=1; 1%); KRAS (n=1; 1%); NRAS (n=1; 1%); and no mutation in RPS15, CCND2, MAPK1, EGR2, BRAF, HIST1H1E, RIPK1, BIRC3. 6 patients had 2 simultaneous gene mutations and 1 patient had 3 (i.e. NOTCH1, ATM and TP53). A mutated IGHV status (IGHV-M) was present in 100 patients (75%) and an unmutated IGHV status (IGHV-U) in 33 patients (25%). IGHV-U was related to both the occurrence of any gene mutation (p<0.001) and the number of gene mutations (p=0.001). NOTCH1 was mutated in 7 out of the 33 IGHV-U patients (21%), but only in 3 out of 99 IGHV-M patients (3%) (p=0.001). XPO1 mutation occurred in 4 IGHV-U patients (12%) and none out of IGHV-M (p<0.001). Two IGHV-U patients showed POT1 mutation (6%), but no IGHV-M case (p=0.014). 9 patients out of 133 (7%) showed BCR-stereotypy. 2 were in cluster CLL#1 (both showing NOTCH1 mutation), 2 in cluster CLL#2 (both of them with SF3B1 mutation), 2 in CLL#4, 1 in CLL#8 (showing NOTCH1 and XPO1 mutations), 1 in CLL#201 (with KLHL6 mutation) and 1 in CLL#202 (with mutations in ATM, TP53 and NOTCH1 genes). In Kaplan-Meier analysis, IGHV-M patients did not reach a median TTT, while IGHV-U had a median of 5.1 years (p<0.001). Stereotypy rate was too low for reliable statistics. At univariate analysis, TTT was only influenced by: IGHV-U (relative risk (RR): 3.9, p<0.001), TP53 mutation (RR: 3.7, p=0.03), % CLL cells (RR: 1.2 per 10% increase, p=0.013), and number of mutations (RR: 1.8 per each mutation, p=0.031). Multivariate Cox regression analysis showed an independent role for IGHV-U status (RR: 3.3, p=0.002) and % CLL cells (RR: 1.2 per 10% increase, p=0.038) Only age showed an impact on OS (RR: 1.2 per decade, p<0.001). Conclusions: 1. The CLL subset without any genomic event by CBA/FISH/genomic array is characterized by very low frequency of IGHV-U status; 2. IGHV-U subgroup showed higher gene mutation rate compared to IGHV-M subgroup, in particular higher NOTCH1, XPO1 and POT1 mutation rate; 3. BCR stereotypy is less frequent than in CLL in general. 4. IGHV-U, as well as the higher disease burden (i.e. % CLL cells), has an independent negative impact on TTT. 5. Requirement for treatment is low and prognosis very favorable in CLL without any genomic event by CBA/FISH/genomic array and a mutated IGHV status. Disclosures Vetro: MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Meggendorfer:MLL Munich Leukemia Laboratory: Employment. Jeromin:MLL Munich Leukemia Laboratory: Employment. Baer:MLL Munich Leukemia Laboratory: Employment. Nadarajah:MLL Munich Leukemia Laboratory: Employment. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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Influence of Karyotype On Overall Survival in Patients with Higher-Risk Myelodysplastic Syndrome Treated with Azacitidine or a Conventional Care Regimen.

Blood ◽

10.1182/blood.v114.22.1755.1755 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1755-1755 ◽

Cited By ~ 5

Author(s):

Ghulam J Mufti ◽

Steven D. Gore ◽

Valeria Santini ◽

Pierre Fenaux ◽

Lewis R. Silverman ◽

...

Keyword(s):

Overall Survival ◽

Board Of Directors ◽

Research Funding ◽

Conventional Care ◽

Complex Karyotype ◽

Trisomy 8 ◽

Employment Equity ◽

Advisory Committees ◽

Cytogenetic Abnormalities ◽

Equity Ownership

Abstract Abstract 1755 Poster Board I-781 Background Karyotypic abnormalities are common in myelodysplastic syndromes (MDS), and specific chromosomal abnormalities are associated with poor prognosis. The phase III AZA-001 study (Lancet Oncol, 2009) showed azacitidine (AZA) prolonged overall survival (OS) regardless of IPSS cytogenetic risk category. This analysis assessed the effects of specific cytogenetic abnormalities on OS in patient (pt) subgroups treated with AZA or a conventional care regimen (CCR). Methods Pts with higher-risk MDS (FAB RAEB, RAEB-t, or CMML and IPSS Int-2 or High) were enrolled and randomized to receive AZA or CCR. CCR comprised 3 treatments: best supportive care only, low-dose ara-C, or induction chemotherapy. Erythropoietins were prohibited. OS was determined in subgroups of pts with del 5/5q-, del 7/7q-, or trisomy 8, each as part of a non-complex karyotype (<3 cytogenetic abnormalities) or as part of a complex karyotype (≥3 cytogenetic abnormalities). OS was also analyzed in pts with combinations of del 5/5q- and/or del 7/7q- as part of non-complex or complex karyotypes (Table). Pt karyotype was determined at baseline. OS was assessed using Kaplan-Meier methods. A stratified Cox proportional hazards regression model was used to estimate hazard ratios (HRs) and associated 95% confidence intervals (CI). Results A total of 358 pts were enrolled (AZA 179, CCR 179). Of them, 153 had normal karyotypes (AZA 77, CCR 76). Median OS in pts with normal karyotypes was not reached at 21.1 months with AZA vs 17.2 months (95%CI: 15.2 – 24.1 months) with CCR; HR = 0.63 (95%CI: 0.39 – 1.03). Of remaining pts, 136 had del 5/5q-, del 7/7q-, and/or trisomy 8 as part of a non-complex or complex karyotype. AZA was associated with longer OS vs CCR in all subgroups of pts with non-complex cytogenetics, with HRs ranging from 0.20 (95%CI: 0.06 – 0.65) to 0.51 (95%CI: 0.05 – 4.74) (Table). In both the AZA and CCR treatment groups, pts in all subgroups with non-complex karyotypes had substantially longer OS than pts with complex karyotypes. Pts with complex karyotypes in some subgroups had longer OS with AZA vs CCR: median OS in pts with del 5/5q-, del 5/5q- WITHOUT del 7/7q-, or trisomy 8 as part of a complex karyotype treated with AZA survived 5.1, 8.0, and 12.4 months longer, respectively, than their counterparts who received CCR. HRs with AZA vs CCR in pts with complex cytogenetics ranged from 0.42 (95%CI: 0.10 – 1.69) to 0.55 (95%CI: 0.29 – 1.05). Conclusions These findings support earlier data showing effectiveness of AZA in higher-risk MDS pts with complex or non-complex karyotypes. Major gains in OS were obtained with AZA vs CCR (12-18 months longer OS with AZA) for the following categories: del 7/7q- (non-complex), del 7/7q- WITHOUT del 5/5q- (non-complex), and trisomy 8 (non-complex and complex). Pts with trisomy 8 treated with AZA experienced a 3-fold increase in median OS compared with similar pts who received CCR. Longer OS (AZA 15.3 vs CCR 7.3 months) was also obtained for pts with del5/5q- WITHOUT del7/7q- as part of a complex karyotype. The worse cytogenetic categories, del 7/7q- and del 5/5q- AND del 7/7q-, both with complex karyotype, were associated with the poorest OS regardless of treatment. Pt subgroups in this post hoc analysis were small and heterogeneous; confirmation of these findings in larger pt samples is warranted. Disclosures Mufti: Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Gore:Celgene: Consultancy, Equity Ownership, Research Funding; Johnson & Johnson: Research Funding. Santini:Celgene: Honoraria. Fenaux:Celgene: Honoraria, Research Funding; Ortho Biotech: Honoraria, Research Funding; Roche: Honoraria, Research Funding; Amgen: Honoraria, Research Funding; Cephalon: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; MSD: Honoraria, Research Funding; Epicept: Honoraria, Research Funding. Skikne:Celgene: Employment, Equity Ownership. Hellstrom-Lindberg:Celgene: Research Funding. Seymour:Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau. Beach:Celgene: Employment, Equity Ownership. Backstrom:Celgene: Employment, Equity Ownership. Fernando:Celgene: Employment, Equity Ownership.

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Comprehensive Molecular Profiling of T-Cell Acute Lymphoblastic Leukemia Identifies Mutations in 76 (97.4%) of 78 Patients

Blood ◽

10.1182/blood.v118.21.2548.2548 ◽

2011 ◽

Vol 118 (21) ◽

pp. 2548-2548

Author(s):

Vera Grossmann ◽

Alexander Kohlmann ◽

Sandra Weissmann ◽

Susanne Schnittger ◽

Valentina Artusi ◽

...

Keyword(s):

Promoter Methylation ◽

Kinase Inhibitors ◽

Lymphoblastic Leukemia ◽

Methylation Status ◽

Normal Karyotype ◽

Genetic Alterations ◽

Cyclin Dependent Kinase ◽

Wild Type ◽

Employment Equity ◽

Equity Ownership

Abstract Abstract 2548 Introduction: At present, the diagnosis of T-ALL is based on immunophenotyping and specific chromosomal rearrangements. However, the knowledge about recurrent somatic mutations is limited. Patients and Methods: We studied a cohort of 78 adult T-ALL cases (n=33 early, n=33 cortical, n=2 mature T-ALL, n=10 subtype not available), including 57 males and 21 females. Age ranged from 18.8–87.7 yrs (median: 42 yrs). A deep-sequencing assay was used to investigate for specific molecular alterations in genes involved in transcriptional regulation: NOTCH1, FBXW7, CDKN2A, DNMT3A, FLT3-ITD, FLT3-TKD, NPM1, PTEN, and RUNX1. Further, chromosome banding analysis and FISH with probes for DNMT3A (2p23), SEC63 (6q21), MYB (6q23), CDKN2A (9p21), PTEN (10q23), CDKN1B (12p13) and TP53 (17p13), as well as CDKN2B promoter methylation analyses were performed. Results: Cytogenetic data was available in 68 patients: normal karyotype: n=22 (2 of these harbored a PICALM-MLLT10-rearrangement), SIL-TAL1-rearrangement: n=3, t(5;14)(q35;q32): n=2, t(10;14)(q24;q11)/t(7;10)(q34;q24): n=9, t(10;11)(p13;q21): n=3, other abnormalities n=29. Importantly, molecular mutations were detected in 67/78 patients (85.6%). In detail, NOTCH1 was the most frequently mutated gene (55/77 cases, 71.4%). Other alterations were detected in DNMT3A (16/78; 20.5%); RUNX1 (13/78; 16.6%); FBXW7 (11/75; 14.6%); PTEN (7/78; 10.0%); CDKN2A (3/58; 5.2%); FLT3-ITD (2/78; 2.5%); and FLT3-TKD (1/70; 1.4%). By FISH analyses, heterozygous deletions of the following loci were observed: DNMT3A (1/43; 2.3%), SEC63 (7/43; 16.3%), PTEN (1/32, 3.1%), CDKN1B (8/43; 18.6%) and TP53 (3/43; 7.0%). CDKN2A deletions were detected in 30/72 (41.6%) cases: n=14 heterozygous, n=15 homozygous, n=1 showed a clone with a heterozygous and a subclone with a homozygous deletion. Further, the CDKN2B promoter methylation status was analyzed. Here, 36/74 (48.6%) cases demonstrated hypermethylation. As such, when combining molecular mutations, CDKN2A deletions, and CDKN2B hypermethylation, in median 2 alterations per case were observed (range 1–5). Moreover, almost every patient (76/78) harbored at least one aberration resulting in a mutation rate of 97.4%. Interestingly, considering alterations in the group of cyclin-dependent kinase inhibitors (CDKN2A/1B deletions, CDKN2A mutations, and CDKN2B hypermethylation), 61/78 (78.2%) cases carried at least one such alteration. With respect to associations amongst molecular mutations, no specific pattern was observed except for a strong correlation between RUNX1 and DNMT3A mutations, i.e. 6/13 RUNX1 mutated cases concomitantly harbored DNMT3A mutations (p=0.021). Furthermore, we observed that DNMT3A and RUNX1 alterations were associated with higher age (DNMT3A: mean±SD 60.9±16 vs. 39.6±16 years; p<0.001; RUNX1: mean±SD 55.4±18 vs. 41.7±18 yrs; p=0.013) whereas PTENmut were associated with younger age (mean±SD 32.9±10 vs. 45.0±19 yrs; p=0.019). With regard to cytogenetics, DNMT3A was significantly correlated with normal karyotype (9/23, 39.1% vs. 6/45, 13.3%; p=0.028). Moreover, RUNX1mut were associated with lower WBC count (mean±SD 26.4±41 vs. 63.4±90 cell count G/L; p=0.025). With respect to immunophenotypes, cases with RUNX1mut showed a trend to be associated with early T-ALLs (9/23, 39.1% vs. 6/45, 13.3%; p=0.082). CDKN2B hypermethylation was significantly correlated with early T-ALLs (21/32, 65.6% vs. 10/31, 32.2%; p=0.012). In contrast, FBXW7mut were associated with the cortical subgroup (1/32, 3.1% vs. 9/32, 28.1%; p=0.013). With regard to clinical outcome, patients with RUNX1mut had a shorter overall survival (OS) compared to RUNX1wt patients (alive at 2 yrs: 44.4% mutated vs. 64.0% wild-type, p=0.011). Further, for NOTCH1mut cases (alive at 2 yrs: 67.4% mutated vs. 33.6% wild-type, p=0.060) a trend towards a better OS was detectable. Conclusions: 1. T-ALL is characterized by a high number of genetic alterations since 46/68 (67.6%) showed cytogenetic aberrations. In addition, at least one molecular alteration was observed in 76/78 (97.4%) patients. 2. The most frequent alterations observed were mutations in NOTCH1, DNMT3A, RUNX1 and FBXW7. 3. The cyclin-dependent kinase inhibitors were altered by deletion, mutation or hypermethylation in 78.2% of cases. 4. RUNX1 mutations are associated with shorter and NOTCH1 mutations with longer OS. Disclosures: Grossmann: MLL Munich Leukemia Laboratory: Employment. Kohlmann:MLL Munich Leukemia Laboratory: Employment. Weissmann:MLL Munich Leukemia Laboratory: Employment. Schnittger:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Artusi:MLL Munich Leukemia Laboratory: Employment. Schindela:MLL Munich Leukemia Laboratory: Employment. Stadler:MLL Munich Leukemia Laboratory: Employment. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Kern:MLL Munich Leukemia Laboratory: Employment, Equity Ownership. Haferlach:MLL Munich Leukemia Laboratory: Employment, Equity Ownership.

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