Chromosomal Aberration Network In Myeloproliferative Neoplasms

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 318-318
Author(s):  
Thorsten Klampfl ◽  
Ashot Harutyunyan ◽  
Tiina Berg ◽  
Bettina Gisslinger ◽  
Francesco Passamonti ◽  
...  
Keyword(s):  
Chromosomal Aberrations ◽  
De Novo ◽  
Myeloproliferative Neoplasms ◽  
Chronic Phase ◽  
Normal Karyotype ◽  
Negative Regulator ◽  
Chromosome 7 ◽  
P53 Pathway ◽  
De Novo Aml ◽  
Insight Into

Abstract Abstract 318 The classical myeloproliferative neoplasms (MPNs) comprise of three entities: polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). Despite distinct phenotypic features of MPN entities they share characteristics like clonal hematopoiesis, risk for thrombosis and bleeding and tendency to transform to secondary acute myeloid leukemia (post-MPN AML). In order to investigate the genetic lesions associated with MPN a large single-center cohort of 311 MPN patients was analyzed for chromosomal aberrations using high resolution Affymetrix SNP 6.0 arrays. The cohort included 150 patients with PV, 90 with ET, 68 with PMF and 3 with post-MPN AML. Of the 311 patients, 144 (46%) had a normal karyotype and 167 (54%) harbored 1 to 8 detectable chromosomal aberrations. We found 51 gains, 102 deletions and 143 uniparental disomies (UPDs). A total of 13 recurrent chromosomal defects (more than three events) were detected. We investigated if either the number of chromosomal aberrations in a patient or specific types of lesions associate with a certain patient group defined by clinical criteria. Chromosomal aberrations were equally distributed among the three MPN entities and only 9pUPD showed significant clustering with PV. We did not detect an association between the number of chromosomal aberrations and disease duration. Patients positive or negative for JAK2 mutations did not differ significantly in the frequency of chromosomal aberrations (except of the association of 9pUPD with JAK2 positive MPN). Patients with complex karyotype were significantly older than patients with normal karyotype (P<0.001). Transformation to post-MPN AML is an important complication in MPN. To investigate associations between chromosomal changes and transformation, we included additional 19 post-MPN AML patients from another center into the study (total N=22). Patients in the post-MPN AML group harbored significantly more chromosomal lesions (P<0.001). Recurrent aberrations of chromosomes 1q, 7p, 7q, 5q, and 3q strongly associated with post-MPN AML. When we reviewed the clinical data of patients in chronic phase MPN harboring the leukemia-associated aberrations, they showed features of disease progression, and some transformed to AML at a later follow-up. We were able to map a common deleted region (CDR) on chromosome 4 to the tet oncogene family member 2 (TET2), a gene frequently deleted in myeloid disorders. On chromosome 7p we mapped a CDR to the Ikaros transcription factor (IKZF1) and a 7q CDR mapped to a novel putative tumor suppressor, the cut-like homeobox 1 gene (CUX1). Interestingly, in one patient who carried a UPD of chromosome 7q we did not detect a mutation in the CUX1 gene but an R288Q mutation was found in the EZH2 gene. Chromosome 7 aberrations in our cohort were strongly linked to post-MPN AML. Our results show that at least three chromosome 7 genes (IKZF1, CUX1, and EZH2) are relevant in leukemic transformation. In addition to chromosome 7, we found gains of chromosome 1q equally relevant in post-MPN AML. We mapped the common 1q amplification to a 3.5 Mbp region that contained the MDM4 gene. Mdm4 is a known negative regulator of p53 and was frequently shown amplified in various cancers. This result prompted us to investigate the relevance of the p53 pathway in post-MPN AML and we sequenced TP53 in all 22 leukemic patients and found mutations in 6 cases (27.3%). Interestingly, none of the patients with TP53 mutation carried an MDM4 amplification. Taken together, 10 out of 22 post-MPN AML cases (45.5%) had evidence of a p53-related defect. To gain deeper insight into the pathways involved in transformation to post-MPN AML we sequenced genes commonly affected in de novo AML, and found two patients with mutations in FLT3, two patients with RUNX1 mutations, two patients with either IDH1 or IDH2 mutations. We conclude that lesions known to play an important role in de novo AML are present only in a fraction of post-MPN AML patients. In this study we show that aberrations of the p53 pathway together with the chromosome 7 lesions affecting IKZF1 and CUX1 are present in 64% of all post-MPN AML patients. Our data give insight into the genetic complexity and heterogeneity of MPN patients in chronic phase as well as in post-MPN AML. The marked genetic heterogeneity of MPN patients will render targeted therapies challenging and underlines the requirement of personalized treatments. Disclosures: No relevant conflicts of interest to declare.

Associations between Chromosomal Aberrations and Functional Impairment of the P53 Pathway in Chronic Lymphocytic Leukaemia.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 953-953
Author(s):  
Andrew R. Pettitt ◽  
Anthony Carter ◽  
Ke Lin ◽  
Paul D. Sherrington ◽  
Mark Atherton ◽  
...  
Keyword(s):  
Functional Analysis ◽  
Functional Impairment ◽  
Chromosomal Aberrations ◽  
Normal Karyotype ◽  
Type A ◽  
Negative Regulator ◽  
Type B ◽  
Prognostic Information ◽  
P53 Pathway ◽  
Negatively Associated

Abstract Adverse prognostic factors in CLL include functional impairment of the p53 pathway [Blood2002;100:1404] and the chromosomal aberrations del 17p13, del 11q23 and +12 [reviewed in Leukemia2002;16:993]. Intriguingly, TP53 is deleted at 17p13, ATM (an important positive regulator of p53) is deleted at 11q23, and MDM2 (an key negative regulator of p53) is amplified in +12. This suggests that p53 dysfunction might account for the deleterious effects of these chromosomal aberrations, and consequently that the two tests might provide similar prognostic information. To define the relationship between p53 dysfunction and karyotype, CLL clones from 178 patients were subjected to p53 functional analysis and interphase FISH for del 17p13, del 11q23, +12 and del 13q14. In order to assign cases with multiple FISH defects to single karyotypic groups, we used an hierarchical model, in which del 17p13, del 11q23, +12 and del 13q14 had a descending order of importance [N Engl J Med2000;343:1910]. The overall frequency of each hierarchical karyotype (17p−, 11q−, +12, and 13q−) was 16.3%, 16.3%, 12.4% and 33.1% respectively. p53 dysfunction, defined as impaired up-regulation of p21 (a transcriptional target of p53) in response to ionizing radiation (IR), was detected in 40.4% of cases using a validated FACS method. 5.1% of cases had the type A defect (baseline p53 increased), 35.4% the type B defect (baseline p53 not increased), and the remainder were classified as having a normal p53 functional response. The distribution of karyotype and p53 functional status is shown in Table 1. Table 1 Karyotype Type A p53 defect Type B p53 defect No p53 dysfunction Total 17p− 7 13 9 29 11q− 1 16 12 29 12+ 1 3 18 22 13q− 0 17 42 59 Normal 0 14 25 39 Total 9 63 106 178 p53 dysfunction was positively associated with 17p− (P < 0.001) and 11q− (P = 0.029), negatively associated with +12 (P = 0.023) and 13q− (P = 0.007), and neither positively or negatively associated with normal karyotype. The frequency of p53 dysfunction in cases with 17p−, 11q−, +12, 13q−, or no FISH defects was 69.0%, 58.6%, 18.2%, 28.8% and 35.9% respectively. The frequency of 17p−, 11q−, +12, 13q−, or no FISH defects was 28.6%, 24.3%, 5.7%, 24.3% and 20.0% respectively in cases with p53 dysfunction, and 8.5%, 11.3%, 17.0%, 39.0% and 23.6% respectively in cases with no detectable p53 dysfunction. Among cases with p53 dysfunction, there was an association between the type A defect and 17p− (P < 0.001). Interestingly, among 17p− cases, the proportion of cells harbouring the 17p13 deletion negatively correlated with the amount of IR-induced p21 up-regulation (r = −0.608, P < 0.001) and positively correlated with baseline p53 levels (r = 0.398, P = 0.033). Indeed, p53 dysfunction was detected in all 15 cases with more than 50% 17p13-deleted cells but in fewer than half of the cases with less than 50% deletion. Together, these findings indicate that adverse karyotype and p53 dysfunction provide overlapping but non-identical information. The association between p53 dysfunction and 17p−/11q− supports the idea of a shared pathogenetic mechanism. On the other hand, the imperfect nature of this association justifies the continued evaluation of p53 functional analysis as a prognostic factor in CLL.

IDH1 and IDH2 Mutations in Therapy-Related Acute Myeloid Leukemia Are Associated with a Normal Karyotype or Der(1;7)(q10;p10) Combined with RUNX1 Mutations,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3514-3514
Author(s):  
Maj K. Westman ◽  
Morten T. Andersen ◽  
Jens Pedersen-Bjergaard ◽  
Mette K. Andersen
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Normal Karyotype ◽  
Chromosome 7 ◽  
Previous Therapy ◽  
Idh Mutations ◽  
Idh1 And Idh2 Mutations ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Abstract 3514 Isocitrate dehydrogenase (IDH) is a metabolic enzyme that catalyzes a reaction in the tricarboxylic acid cycle. Gain of function mutations in the IDH1/2 genes have been reported in different malignancies and are observed in 15–30% of de novo AML with association to a normal karyotype and to NPM1 mutations. The exact role of IDH1/2 mutations in leukemogenesis remains to be determined. IDH mutations have not previously been studied in a cohort of therapy-related myelodysplasia (t-MDS) and therapy-related acute myeloid leukemia (t-AML). To evaluate the frequency of IDH1/2 mutations in t-MDS and t-AML, and their possible association to type of previous therapy and to other genetic abnormalities, DNA from 140 well-characterized patients with t-MDS (n=89) and t-AML (n=51) were analyzed with high-resolution melting followed by sequencing. All patients have previously been examined cytogenetically and investigated for mutations in 12 other genes: FLT3(ITD, TKD), KIT, JAK2, KRAS, NRAS, BRAF, PTPN11, RUNX1, MLL(ITD), CEBPA, NPM1, and TP53. In total, IDH mutations were detected in 12 of 140 patients (9%). 3 patients had a mutation in IDH1 and 9 patients had a mutation in IDH2 (Table 1), all mutations previously reported in de novo AML. No patients had concurrent IDH1 and IDH2 mutations. IDH mutations were not related to previous therapy with alkylating agents, topoisomerase II inhibitors or radiotherapy, but were significantly associated with other types of therapy not firmly established to be leukemogenic (p=0.004). The latency period to development of t-MDS/t-AML was not different between IDH1/2 positive (+) cases and cases with IDH (wt) (64 and 48 months, respectively, p=0.118). 4/5 cases with t-MDS and IDH+ progressed to AML compared to 27/84 t-MDS cases with IDHwt (p=0.048).Table 1:Characteristics of 12 patients with t-MDS/t-AML and mutations in IDH1/2CaseAge/sext-AML/t-MDSPrevious therapyKaryotypeOther mutationsIDH Mutation1974/FAMLAlk45,XX,-7/48,XX,der(1;7)(q10;p10),+11, +13/46,XX–IDH1 R132G2963/FAMLRT46, XXNPM1 FLT3-ITDIDH1 R132G3663/FAMLAlk46,XX,+2,+8/47,XX,der(6)t(1;6) (q?25;p21),+8N-RASIDH2 R172K4472/MMDSAlk46,XY,+1,der(1;7)(q10;p10)/46,XY–IDH2 R140Q5562/FMDS→AMLRT46, XXRUNX1IDH2 R140L7272/FMDS→AMLAlk, T II, RT46,XX,+1,der(1;7)(q10;p10)/50,XX,idem, +8,+9,14+21RUNX1IDH2 R140Q8178/MMDS→AMLAlk46,XY,der(17)t(11;17)(q13;p13),i(13) (q10)/47,idem,+der(13)t(11;13) (q13;p11)IDH2 R172K10443/FMDS→AMLAlk47,XX,+1,der(1;7)(q10;p10),+8RUNX1IDH1 R132C10944/FAMLMtx, Aza46, XXIDH2 R140Q11952/FAMLAlk, T II, RT46, XXNPM1IDH2 R140Q13325/MAMLVCR, MTX, Asp,6-MP46, XXIDH2 R140Q18060/MMDS→AMLMtx46, XXMLL-ITDIDH2 R140Q6-MP, 6 mercaptopurine; Alk, alkylating agent; Asp, l-asparaginase; Aza, azathioprine; Mtx, methotrexate; RT, radiotherapy, T II, topoisomerase inhibitor, VCR, vincristine. IDH mutations were significantly associated with a normal karyotype (6/12 cases with IDH+ vs. 18/128 with IDHwt, p=0.006) and der(1;7)(q10;p10) resulting in trisomi 1q and loss of 7q (4/12 cases with IDH+ vs. 7/128 with IDHwt, p=0.008), but was inversely correlated to other chromosome 7 abnormalities (1/12 cases with IDH+ vs. 54/128 with IDHwt, p=0.03). No patient with mutated IDH had chromosome 5 abnormalities, TP53 mutations or recurrent balanced translocations. 7/12 patients with mutated IDH1/2 had other gene mutations characteristic of AML (Table 1). The frequency of each of these other mutations were not different from patients with wildtype IDH1/2 (RUNX1, p=0.4; NPM1, p=0.2; FLT3, p=1.0; MLL, p=0.165; N-RAS, p=1.0). In conclusion, mutations of IDH1/2 were observed in 9% of patients with t-MDS/t-AML. They were not related to any specific type of therapy but perhaps associated with transformation from MDS to AML. IDH mutations clustered in the genetic pathway characterized by a normal karyotype and mutations of NPM1, and the pathway characterized by 7q−/−7 and RUNX1 point mutations. The significant association observed between IDH1/2 mutations and der(1;7)(q10;p10) may indicate that this cytogenetic aberration represents a specific entity, biologically distinct from other chromosome 7 abnormalities. This is also supported by the different clinical outcome between cases with der(1;7) and other cases with -7/7q- (Sanada et al, Leukemia 2007). Disclosures: No relevant conflicts of interest to declare.

Fusion Gene Detection Using Whole Transcriptome Analysis in Patients with Chronic Myeloproliferative Neoplasms and Secondary Acute Myeloid Leukemia

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4093-4093 ◽  
Author(s):  
Fiorella Schischlik ◽  
Jelena D. Milosevic Feenstra ◽  
Elisa Rumi ◽  
Daniela Pietra ◽  
Bettina Gisslinger ◽  
...  
Keyword(s):  
Myeloid Leukemia ◽  
Research Funding ◽  
De Novo ◽  
Fusion Gene ◽  
Myeloproliferative Neoplasms ◽  
Chronic Phase ◽  
Loss Of Function ◽  
Secondary Aml ◽  
De Novo Aml ◽  
Whole Transcriptome

Abstract Fusion oncogenes resulting from chromosomal aberrations are common disease drivers in myeloid malignancies. The most prominent example is BCR-ABL1 fusion present in chronic myeloid leukemia, which together with essential thromobocythemia (ET), primary myelofibrosis (PMF) and polycythemia vera (PV) belongs to the classic myeloproliferative neoplasms (MPN). The BCR-ABL1 negative MPNs are driven by somatic mutations in JAK2, MPL and CALR. MPN patients can progress to acute myeloid leukemia (AML) but the transformation process is not well understood. Studies using standard karyotyping and SNP microarrays have shown that disease progression is characterized by an increase in karyotype complexity. We aimed to identify novel fusion oncogenes in patients with BCR-ABL1 negative MPN during chronic phase and disease progression in high-throughput and cost-efficient manner using RNA-seq technology. In addition this approach enabled us to perform RNA-seq variant calling for identification of gene mutations on the same cohort of patients. Whole transcriptome sequencing was performed on 121 patients (112 chronic phase MPN and 9 secondary AML samples) and 23 healthy controls in a 100 base pair paired-end manner. The cohort consisted of 44% PMF, 22% ET, 12% PV and 6% secondary AML patients. The output of three fusion detection tools (Defuse, Tophat-fusion and SOAPfuse) was combined in order to increase sensitivity. Extensive filtering steps were applied in order to enrich for cancer specific fusion events, including filtering for fusions appearing in healthy individuals, filtering for read-throughs and false positives with external databases and manual inspection of sequencing reads. The outcome of analysis for Defuse, Tophat-fusion and SOAPfuse resulted in the total of 52, 54 and 38 candidate fusions, respectively. Candidate fusions were Sanger-sequenced and for Tophat-fusion and Defuse the validation rate was 60%, while for SOAPfuse only 20% could be validated. Approximately 70% of the fusion candidates were not shared among the 3 tools which underlines the importance of selecting the union of all calls from each tool rather than the intersect. We did not observe clustering of breakpoints along the genome. Most fusion candidates could be detected in PMF which corresponds to the disease entity that was most represented in the cohort (44% of patients). No enrichment for fusions was found in 7 triple negative (no JAK2, CALR, MPL mutations) cases. 42% of chromosomal aberrations were translocations, followed by duplication (31%), inversion (14%) and deletion events (11%). Among the intragenic fusions, approximately half had genomic breakpoints less than 1 Mb apart. 70% of validated fusions were out of frame, while 28% were in frame. In the leukemic samples a higher abundance of fusions was found (4/9). Typical fusions for de novo AML were not detected within secondary AML (sAML) samples. We did not detect a recurrent fusion oncogene in our patient cohort. In a PMF patient with JAK2-V617F mutation we identified a BCR-ABL1 fusion, indicating a clonal exchange which was consistent with patient's phenotype. Another PMF patient exhibited an inversion event involving the first exon of CUX1, causing a CUX1 loss of function. Other fusions in chronic MPN patients affected genes involved in histone modifications (SMYD3-AHCTF1, KDM4B-CYHR1). In post-MPN AML patients we identified a somatic in frame-fusion involving INO80D and GPR1 and a fusion truncating the first 3 exons of RUNX2 (XPO5-RUNX2). The high quality of RNA sequencing data, allowed us to set up a variant detection workflow that will be compared with matched samples that have been exome sequenced. Preliminary results could demonstrate that mutations in the JAK2 gene in a cohort of 96 patients were all correctly recalled, emphasizing its sensitivity. Fusion events among patients in chronic phase MPN are rare and the majority of these events imply loss of function of both fusion gene partners. This approach adds valuable information on the true frequency of inactivation of genes such as CUX1 in patients, as small inversions like the one described above would not be detectable by other methods. Detection of a subclone with BCR-ABL1 fusion underlines the strength of the fusion detection workflow for diagnostic purposes. Typical de novo AML fusions were not found in sAML and further suggests that de novo AML and sAML are distinct disease entities on a genetic level. Disclosures Gisslinger: Janssen Cilag: Honoraria, Speakers Bureau; Sanofi Aventis: Consultancy; AOP ORPHAN: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Research Funding, Speakers Bureau; Geron: Consultancy. Kralovics:AOP Orphan: Research Funding; Qiagen: Membership on an entity's Board of Directors or advisory committees.

High Frequency of AML1/RUNX1 Mutations in Specific Cytogenetic Subgroups in De Novo Acute Myeloid Leukemia.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 986-986
Author(s):  
Frank Dicker ◽  
Claudia Haferlach ◽  
Wolfgang Kern ◽  
Torsten Haferlach ◽  
Susanne Schnittger
Keyword(s):  
Trisomy 21 ◽  
De Novo ◽  
Normal Karyotype ◽  
Clinical History ◽  
Trisomy 13 ◽  
Complex Karyotype ◽  
Trisomy 8 ◽  
Cytogenetic Aberrations ◽  
De Novo Aml ◽  
Acute Myeloid

Somatic mutations in the DNA-binding domain, the socalled Runt homology domain, of the AML1/RUNX1 gene have been identified to occur in acute myeloid leukaemia (AML) with the highest incidence in AML M0, in therapy-related myelodysplastic syndrome (t-MDS), in therapy-related AML (t-AML) and AML after MDS (s-AML). Cytogenetic aberrations that are associated with RUNX1 mutations (RUNX1mut) have been reported to be trisomy 13 in AML and trisomy 21 in myeloid malignancies, but also loss of chromosome 7q, mainly in t-MDS but rarely in t-AML. So far the majority of RUNX1mut have been described in secondary or therapy-related cases. Thus, we characterized a cohort of 119 patients (pts) with de novo AML and compared these results to 19 MDS and s-AML, 2 t-MDS (n=2) and 8 t-AML. The cohort was selected for specific cytogenetics with high reported frequencies of RUNX1mut: trisomy 13 (n=17), trisomy 21 (n=9), −7/7q- (n=34). In addition pts with normal karyotype (NK) (n=42), inv(3)/t(3;3) (n=12), trisomy 8 (n=11), complex karyotype (n=13) and 10 pts with various other cytogenetic aberrations (other) were analyzed. The incidence of RUNX1mut in the different cytogenetic subgroups was: 94% (16/17) in +13, 56% (5/9) in +21, 29% (10/34) in −7/7q-, 10% (4/42) in NK, 17% (2/12) in inv(3)/t(3;3), 18% (2/11) in +8, 0% (0/13) in complex karyotype and 20% (2/10) in other, respectively. Based on clinical history we observed RUNX1 mutations in: 6/19 (32%) in MDS/s-AML, 1/10 (10%) in t-MDS/t-AML and 34/119 (29%) in de novo AML. Of the 6 RUNXmut cases with MDS/s-AML the karyotypes were heterogeneous NK (n=1), −7 (n=2) +13 (n=1), +21 (n=1), and inv(3) (n=1). The only recurrent cytogenetic aberration in MDS/s-AML was −7, thus the frequency of RUNXmut in the MDS/s-AML group with −7 was 2/8 (25%). Also the only RUNX1mut case with t-AML revealed a −7. These data correspond to those reported in the literature. We further focussed on the analyses of RUNX1 in de novo AML which is rarely reported so far. In the de novo AML group only we detected RUNX1mut with the highest frequency in +13 (16/16; 100%) followed by +21 (4/8; 50%) −7 (7/21; 33%), + 8 (2/10, 20%), inv(3) (1/8; 12.5%), and NK (3/33; 9.1%). In addition, in the group with “other” aberration 2/8 were mutated. Interestingly, these 2 mutated cases displayed a high number of trisomies including +8 and +13. No RUNX1mut were detected in AML with complex karyotype (n=10). These data for the first time show that RUNX1mut are not strongly correlated to MDS, s-AML or t-AML. With almost the same frequency they can be observed in de novo AML if specific cytogenetic groups are considered. Thus the RUNXmut seem to be more related to these cytogenetic subgroups than to the MDS, s-AML or t-AML.

Bortezomib+Chemotherapy Based Salvage Combinations in Refractory AML, Preliminary Results

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4000-4000
Author(s):  
Miklos Udvardy ◽  
Attila Kiss ◽  
Bela Telek ◽  
Robert Szasz ◽  
Peter Batar ◽  
...  
Keyword(s):  
Cell Lines ◽  
De Novo ◽  
Case Reports ◽  
Fatal Outcome ◽  
Normal Karyotype ◽  
Secondary Aml ◽  
Poor Risk ◽  
Group 2 ◽  
De Novo Aml ◽  
Group 1

Abstract Bortezomib (Velcade) proved to be the standard element of refractory myeloma 2nd and 3rd line treatment, while many studies are suggesting excellent results in 1st line. Proteasome inhibition, the block of angiogenesis, modification of the NF-kappa-B system seems to be a challenging target in other malignant diseases, including refractory acute myeloid leukemia (AML), as well. In vitro data clearly support, that bortezomib exerts antiproliferative and pro-apoptotic effects in different AML cell-lines, along with human AML cell cultures, and moreover bortezomib was able to restore, or at least improve anthracyclin and possibly ARA-C sensitivity in different cell-lines (including AML). More recently, a Phase I trial showed bortezomib monotherapy efficient (only in few percents) in childhood refractory acute leukemia. Some case reports were shown at ASH 2007. We have tried bortezomib containing first or second line combinations in 27 (14 female, 13 male, mean age 57.6 years) patients with refractory or poor risk AML, in a small retrospective survey. The combinations were as follows: HAM or Flag-Ida, combined with bortezomib 1,3 mg pro sqm, day O and seven). The following groups were considered as refractory or poor risk AML: De novo AML, 2nd line: No response/remission to first line standard treatment (“3+7”), n=2 (Velcade- Flag-Ida treatment) De novo AML 1st line: bilineal or biphenotypic (flow-cytometry) n=2 (Velcade-Flag- Ida treatment) De novo AML with complex (numerical or more than 3 abnormalities) karyotype or normal karyotype with flt-3 TKD mutation, n=9, 1st line (Velcade-Flag-Ida n=6, Velcade- HAM protocol, n=3) Secondary AML or AML with evidence of previous more than 6 mo duration high grade MDS, n=14, 1st line: (Velcade-Flag-Ida n=9, Velcade-HAM n=5) RESULTS: Complete remission (CR) 12/27, partial remission (PR) 9/27, no remission 5/27, progression during treatment: 1/27.Best responses were seen in de novo cases. CR had been achieved in all patients of group 1 (two standard risk patients not responding to 3+7 protocol), and group 2 (biphenotypic, bilineal). The CR rate was quite appreciable in group 3, i.e. 6/9 (complex karyotype or normal karyotype with FLt-3 mutation – the response rate was excellent with flt-3 mutated cases). In group 4. (MDS, secondary AML) the results were less impressive. There were no major differences according to protocol (Flag-Ida or HAM) Allogeneous stem cell transplantation could have been performed in 1st CR in two patients (one from group 1. and another from group 2.). One of them died due to relapse, the other one is in CR since then. The combinations seem to be relatively safe. Induction related death rate was low (1 elderly patient acute thrombocytopenic bleeding with refractory MDS-AML). 5 other patients had severe neutropenic sepsis (2 with fatal outcome). Pulmonary syndrome, which may follow Velcade+ARA-C had not been documented. Other adverse events did not differ from the pattern observed with standard induction therapies.

TET2 and ASXL1 Mutations in Leukemic Transformation of Chronic Myeloproliferative Neoplasms.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2894-2894 ◽  
Author(s):  
Omar Abdel-Wahab ◽  
Taghi Manshouri ◽  
Jay Patel ◽  
Kelly Harris ◽  
Jin Juan Yao ◽  
...  
Keyword(s):  
De Novo ◽  
Myeloproliferative Neoplasms ◽  
Myeloproliferative Neoplasm ◽  
Leukemic Transformation ◽  
Exact Test ◽  
Chronic Myeloproliferative Neoplasms ◽  
Secondary Acute Myeloid Leukemia ◽  
Paired Samples ◽  
Mutational Status ◽  
De Novo Aml

Abstract Abstract 2894 Poster Board II-870 Recent studies have identified TET2 and ASXL1 mutations in myeloid malignancies, suggesting that acquisition of these mutant alleles might precede the acquisition of JAK2 in some myeloproliferative neoplasm (MPN) patients. Moreover, the observation that JAK2 mutations are observed in minority of patients with leukemic transformation of JAK2-mutant MPNs suggests the possibility that JAK2 mutations are dispensable for leukemic transformation. However the role of TET2 and ASXL1 mutations in leukemic transformation has not been evaluated. We therefore investigated the mutational status of JAK2, TET2, and ASXL1 in 63 patients with leukemic transformation from a pre-existing MPN, including 49 unpaired secondary acute myeloid leukemia (sAML) samples and 14 patients for whom paired MPN and sAML samples were available. Mutations of TET2 and ASXL1 were found at a higher frequency in sAML samples transformed from MPNs than reported for sporadic MPNs (9/46 (19.6%) and 7/46 (15.2%), respectively). This was also higher than the mutational frequency of TET2 and ASXL1 in de novo AML (6.4% (3/47) and 4.3% (2/47), respectively) but similar to that of AML transformed from MDS (12.8% (5/39) and 15.4% (6/39)). All possible genetic combinations of JAK2, TET2, and ASXL1 status were observed in sAML patients. Analysis of paired samples reveal that TET2 mutations are far more likely to occur at leukemic transformation of MPN than at MPN diagnosis (p=0.013, Fisher's exact test) whereas ASXL1 mutations were equally likely to occur at MPN or sAML. Although mutations in JAK2 and in TET2 may not be retained at leukemic transformation from MPN, mutations in ASXL1 at MPN diagnosis were consistently retained at leukemic transformation. In addition, individual cases were observed where TET2 and/or ASXL1 mutations were found before acquisition of JAK2 mutations or clinical evidence of MPN, as well as cases where TET2 and ASXL1 mutations were acquired during leukemic transformation of a JAK2V617F-positive clone. These data suggest the mutational order of events in MPN and sAML pathogenesis might vary in different patients, and that TET2 and ASXL1 mutations might contribute in different patients to the development of MPN and/or to leukemic transformation. In addition, the identification of transformed AML cases with no evidence of pre-existing JAK2, TET2, and ASXL1 mutations indicates the existence of other, not yet identified, mutations necessary for leukemic transformation of MPNs. Disclosures: Levine: Novartis: Research Funding; TargeGen: Consultancy. Verstovsek:Incyte: ; Exelixis: ; Cephalon: ; SBIO: ; AstraZeneca: .

NPM1 Mutations Have a High Impact On the Development of Secondary AML.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 999-999
Author(s):  
Susanne Schnittger ◽  
Tamara Weiss ◽  
Frank Dicker ◽  
Jana Sundermann ◽  
Wolfgang Kern ◽  
...  
Keyword(s):  
De Novo ◽  
Myeloproliferative Neoplasms ◽  
Blast Crisis ◽  
Nras Mutation ◽  
Npm1 Mutation ◽  
Secondary Aml ◽  
Second Hit ◽  
Total Cohort ◽  
Equity Ownership ◽  
De Novo Aml

Abstract Abstract 999 Poster Board I-21 NPM1 mutations are frequently reported to be typical for de novo AML and are regarded as prognostically favorable if not associated with FLT3-ITD. These mutations have rarely been reported in secondary AML after myelodysplastic syndrome (MDS) or after myeloproliferative neoplasms (MPN). We have detected NPM1 mutations in 37/283 patients with AML after a previous MDS (s-AML) (13.1%) and in 6/67 after a previous MPN (9%). Here we describe the characteristics of these 43 NPM1 mutated s-AML cases to show the involvement of NPM1 mutations in development of secondary AML. The total cohort of 43 cases was composed of 22 males and 21 females with a median age of 71.3 years (range: 29.3-87.7 years). Cytogenetics was available in 40 of the 43 cases (93%). 27 of these had a normal karyotpye whereas 13 revealed one of these aberrations: +4 (n=3), t(1;14)(p34;q32) (n=1); -7 (n=1), del(9q) (n=2), +13 (n=1); +21 (n=1), -Y (n=1); i(X)(p10) (n=1), [+1,der(1;13)(q10;q10),+i(5)(p10),+8] (n=1) and a t(5;12)(q33;p13) (n=1). All 43 samples were analysed for MLL-PTD, FLT3-ITD, FLT3-TKD, NRAS, CEBPA, RUNX1 mutations as well as for KITD816 and JAK2V617F mutations. The incidence of additional cooperating mutations was similar to de novo AML. FLT3-ITD was detected in 14/37 AML after MDS (37.8%) and only once (1/6) after MPN. FLT3-TKD was observed in 3/37 case after MDS (8.1%) and never after MPN. In addition there was one case with RUNX1 and 4 cases (10.8%) with NRAS mutation after MDS. In none of the cases a CEBPA mutation or MLL-PTD was observed. Thus a total of 18/37 cases (48.8%) after MDS revealed a further molecular mutation in addition to NPM1. Of those without additional molecular mutations (only NPM1) 4 cases revealed cytogenetic aberrations resulting in 22/37 cases (59.5%) with additional cytogenetic or molecular mutations. Also in the 6 cases with NPM1 after MPN we detected a high proportion of additional mutations. Two of these 6 cases defined to be after MPN had a history of KITD816V mutated mastocytosis. Two further cases had preceding JAK2V617F mutated MPN and one additional carried an ETV6-PDGFRB rearrangement. In all these 5 transformed MPN cases the initial typical MPN mutation was retained in AML (blast crisis) whereas the NPM1 mutation was acquired and may have served as a second hit in the development to AML. One of the two JAK2+/NPM1+ cases in addition also acquired an FLT3-ITD. From 11 of the s-AML cases a paired sample from the timepoint of MDS was available. Retrospectively the NPM1 mutations was retraced by mutation specific realtime PCR and also all other markers were analysed. Three different patterns were observed: 1) in two cases the NPM1 mutation was not detectable in MDS (analysed 35 and 11 months before diagnosis of s-AML). In one case an NPM1/ABL1 level of 1.6% was detectable 6 months after diagnosis of MDS and a level of 2129% eleven months after diagnosis of MDS. 2) In six cases the NPM1 mutation was not detectable with standard methods in MDS, but with sensitive Real time PCR a ratio of 1-4 log below the s-AML level was already detectable 6-17 months before onset of s-AML. 3) In three further cases a high NPM1 level comparable to that in s-AML was already detectable in MDS 2-12 months before s-AML evolved. These three cases gained an FLT3-ITD at the time point of transformation from MDS to AML. These pattern show that NPM1 can be an early or a late event in transformation to s-AML and although the acquisition of mutations seems to be important in the transformation to AML the sequence of the single events seem to be secondary. As NPM1 have a favourable prognosis in de novo AML if not associated with FLT3-ITD we did a respective analysis for overall survival (OS) and (EFS) for our cohort of s-AML after MDS. For this analysis 278 s-AML patients were available: NPM1-/FLT3- (n=223); NPM1+/FLT3- (n=20), NPM1-/FLT3+ (n=20) and NPM1+/FLT3+ (n=12). The total cohort revealed a bad outcome (median OS: 56.6 days and median EFS: 43.5 days; range 2-1049 days for both). The median time for MDS until transformation to AML was 316 days (range: 15-6310 days). No difference with respect to outcome was detected between the four different molecular genetic subgroups. In conclusion, these data 1) show that NPM1 mutations play a major role in the evolution of AML following MDS or MPN. 2) NPM1 mutations can be the first as well as the second hit during transformation. 3) Support the theory of a multistep genetic principle in development of secondary AML. 4) s-AML with a NPM1+/FLT3-ITD- status can not be regarded as prognostically favorable. Disclosures: Schnittger: MLL Munich Leukemia Lab: Equity Ownership. Weiss:MLL Munich Leukemia Lab: Employment. Dicker:MLL Munich Leukemia Lab: Employment. Sundermann:MLL Munich Leukemia Lab: Employment. Kern:MLL Munich Leukemia Laboratory: Equity Ownership. Haferlach:MLL Munich Leukemia Lab: Equity Ownership. Haferlach:MLL Munich Leukemia Lab: Equity Ownership.

Mutational Spectrum Analysis of Interesting Correlation and Interrelationship Between RNA Splicing Pathway and Commonly Targeted Genes in Myelodysplastic Syndrome

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 273-273 ◽  
Author(s):  
Yasunobu Nagata ◽  
Masashi Sanada ◽  
Ayana Kon ◽  
Kenichi Yoshida ◽  
Yuichi Shiraishi ◽  
...  
Keyword(s):  
Rna Splicing ◽  
Genetic Basis ◽  
De Novo ◽  
Gene Mutations ◽  
Myeloid Neoplasms ◽  
Disease Subtypes ◽  
The Difference ◽  
De Novo Aml ◽  
Insight Into ◽  
Splicing Machinery

Abstract Abstract 273 Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid neoplasms showing a frequent transition to acute myeloid leukemia. Although they are discriminated from de novo AML by the presence of a preleukemic period and dysplastic cell morphology, the difference in molecular genetics between both neoplasms has not been fully elucidated because of the similar spectrum of gene mutations. In this regards, the recent discovery of frequent pathway mutations (45∼90%) involving the RNA splicing machinery in MDS and related myeloid neoplasm with their rare mutation rate in de novo AML provided a novel insight into the distinct molecular pathogenesis of both neoplasms. Thus far, eight components of the RNA splicing machinery have been identified as the targets of gene mutations, among which U2AF35, SF3B1, SRSF2 and ZRSR2 show the highest mutation rates in MDS and CMML. Meanwhile, the frequency of mutations shows a substantial variation among disease subtypes, although the genetic/biological basis for these differences has not been clarified; SF3B1 mutations explain >90% of the spliceosome gene mutations in RARS and RCMD-RS, while mutations of U2AF35 and ZRSR2 are rare in these categories (< 5%) but common in CMML (16%) and MDS without increased ring sideroblasts (20%). On the other hand, SRSF2 mutations are most frequent in CMML (30%), compared with other subtypes (<10 %) (p<0.001) (Yoshida K, et al, unpublished data). So to obtain an insight into the genetic basis for these difference, we extensively explored spectrums of gene mutations in a set of 161 samples with MDS and related myeloid neoplasms, in which mutations of 10 genes thus far identified as major targets in MDS were examined and their frequencies were compared with regard to the species of mutated components of the splicing machinery. The mutation status of the 161 specimens was determined using the target exon enrichment followed by massively parallel sequencing. In total, 86 mutations were identified in 81(50%) in the 8 components of the splicing machinery. The mutations among 4 genes, U2AF35 (N = 20), SRSF2 (N = 31), SF3B1 (N = 15) and ZRSR2 (N = 10), explained most of the mutations with a much lower mutational rate for SF3A1 (N = 3), PRPF40B (N = 3), U2AF65 (N = 3) and SF1 (N = 1). Conspicuously, higher frequency 4 components of the splicing machinery were mutated in 76 out of the 161 cases (47.2%) in a mutually exclusive manner. On the other hand, 172 mutations of the 10 common targets were identified among 117, including 41 TET2 (25%), 32 RUNX1 (20%), 26 ASXL1 (16%), 24 RAS (NRAS/KRAS) (15%), 22 TP53 (14%), 17 IDH1/2 (10%), 10 CBL (6%) and 10 EZH2 (6%) mutations. We examined the difference between the major spliceosome mutations in terms of the number of the accompanying mutations in the 10 common gene targets. The possible bias from the difference in disease subtypes was compensated by multiple regressions. The SRSF2 mutations are more frequently associated with accompanying gene mutations with a significantly higher number of those mutations (N=29; OR 6.2; 95%CI 1.1–35) compared with that of the U2AF35 mutations (N=14) (p=0.038). Commonly involving the E/A splicing complexes, these splicing pathway mutations lead to compromised 3' splice site recognition. However, individual mutations may still have different impacts on cell functions, which could contribute to the determination of discrete disease phenotypes. It was demonstrated that SRSF2 was involved in the regulation of DNA stability and that depletion of SRSF2 can lead to DNA hypermutability, which may explain the higher number of accompanying gene mutation in SRSF2-mutated cases than cases with other spliceosome gene mutations. In conclusion, it may help to disclosing the genetic basis of MDS and related myeloid neoplasms that highly paralleled resequencing was confirmed SRSF2 mutated case significantly overlapped common mutations. Disclosures: No relevant conflicts of interest to declare.

First-in class selective AXL inhibitor bemcentinib (BGB324) in combination with LDAC or decitabine exerts anti-leukaemic activity in AML patients unfit for intensive chemotherapy: Phase II open-label study.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 7043-7043 ◽  
Author(s):  
Sonja Loges ◽  
Michael Heuser ◽  
Jörg Chromik ◽  
Carlos Enrique Vigil ◽  
Peter Paschka ◽  
...  
Keyword(s):  
Phase Ii ◽  
De Novo ◽  
Negative Regulator ◽  
Second Phase ◽  
Intensive Chemotherapy ◽  
Open Label ◽  
Open Label Study ◽  
Tumour Immunity ◽  
De Novo Aml ◽  
Grade 3

7043 Background: The RTK AXL represents a therapeutic target promoting AML cell proliferation and survival by pleiotropic mechanisms and is a negative regulator of anti-tumour immunity. Bemcentinib is a first-in-class, highly selective, oral AXL inhibitor that has previously shown encouraging anti-leukaemic activity as a monotherapy in r/r AML and hr-MDS. Methods: A monotherapy dose-escalation and expansion part of this trial is complete. In this second, phase II part of the study, 11 and 15 AML pts unfit for intensive chemotherapy received bemcentinib at RP2D (200 mg po/d) in combination with low-dose cytarabine (LDAC) and decitabine, respectively. Median age was 77 yr (range: 50-83), median screen myeloblast count 39% (3-95%) and 2/19 (11%) of pts evaluable for FLT3 were FLT3+. Plasma protein biomarker levels were measured using the DiscoveryMap v3.3 panel (Myriad RBM) at screen and following treatment. Results: The most common TRAEs (≥ 15% of pts) were ECG QT prolongation (35%) and diarrhoea (15%). Among these, 3 were Grade 3, and none 4 or 5. All TRAEs were manageable and/or reversible. As of Feb ‘19, 9 pts (2 de novo, 1 secondary, 6 r/r) in the bemcentinib + LDAC group were evaluable for response and 4 (44%; 2 de novo + 2 relapsed) achieved rapid CRi at C2D1. Responses were durable (range: 7 – 11 cycles) in 3 of the 4 responders. A further 2 pts (22%, 1 secondary + 1 relapsed) achieved durable SD (5 and 6 cycles). mPFS among the 5 pts with durable CRi or SD was 5 months (range: 3.5-7.7). Further, at the time of writing, 11 pts (8 de novo, 3 r/r) in the bemcentinib + decitabine group were evaluable for response of which 4 (36%, all de novo) achieved CRi after ≥ 4 cycles. One additional de novo pt achieved durable SD lasting for 5 cycles. Conclusions: Bemcentinib in combination with LDAC exerted early durable responses in patients with both de novo and relapsed AML whilst the combination of bemcentinib + decitabine exerted comparably fewer and later responses in de novo AML. Soluble biomarker correlations will be presented at the meeting. Both combinations were generally well-tolerated and further exploration is warranted. Clinical trial information: NCT02488408.

scholarly journals Low Incidence of V617FJAK2 Mutation in Acute Myeloid Leukemia and Myelodysplastic Syndromes

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4957-4957
Author(s):  
Gueorgui Balatzenko ◽  
Branimir Spassov ◽  
Yanica Georgieva ◽  
Vasil Hrischev ◽  
Margarita Guenova
Keyword(s):  
Acute Myeloid Leukemia ◽  
Myelodysplastic Syndromes ◽  
Myeloid Leukemia ◽  
De Novo ◽  
Myeloproliferative Neoplasms ◽  
Polymorphism Analysis ◽  
Jak2 Mutation ◽  
Mutation Status ◽  
De Novo Aml ◽  
Acute Myeloid

Abstract Background: V617F JAK2 mutation is a typical molecular finding in BCR-ABL-negative myeloproliferative neoplasms (MPN). The same abnormality has also been reported in other myeloid malignancies. However, the data regarding the incidence and clinical relevance of V617F JAK2 in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are conflicting. Aim: To establish the incidence and clinical significance of V617F JAK2 mutation in AML and MDS patients in our institution. Materials and Methods : AML and MDS patients with isolated bone marrow mononuclear cells were included in this study, as follows: (i) 139 AML patients (71 females; 68 males; mean age of 57.5±15.3 years), including: 122 - de novo AML, 7 - therapy related AML (t-AML) and 10 - secondary AML (sAML) after primary MPN [3 V617F JAK2(+), 2 V617F JAK2(-) and 5 with unknown initial V617F JAK2 status]; (ii) 35 MDS patients. V617F JAK2 mutation status was determined using allele-specific polymerase chain reaction (PCR) and PCR RFLP (Restriction Fragment Lenght Polymorphism) analysis. Results: V617F JAK2 mutation was detected in 3 AML patients: (i) in 1/122 (0.8%) de novo AML patients - male patient with minimally differentiated AML, with no antecedent MPN and the leukemic population showed aberrant myeloid phenotype with co-expression of CD7 and overexpression of EVI1 gene, (ii) in 2/10 (20.0%) patients with sAML after MPN and both patients had V617F JAK2(+) sAML after V617F JAK2(+) primary myelofibrosis. Interestingly; in the same group, a female patient with V617F JAK2(+) essential thrombocythemia developed 5 years later V617F JAK2(-) sAML with an aberrant myelomonocytic phenotype and co-expression of CD56. None of the patients with t-AML or MDS tested positive for V617F JAK2. Conclusion: V617F JAK2 mutation is a rare finding in AML and MDS patients. Higher incidence was observed in sAML after MPN. However, the mutation status at the AML stage may not be identical as that detected during the primary MPN. Disclosures No relevant conflicts of interest to declare.

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