Trisomy 8 in the Light of Recent Cytogenetic Classification Advances. A Study From the French Acute Myeloid Leukemia Intergroup.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2594-2594 ◽  
Author(s):  
Nicolas Boissel ◽  
Christine Terré ◽  
Pascale Cornillet-Lefebvre ◽  
Odile Maarek ◽  
Eric Lippert ◽  
...  

Abstract Abstract 2594 Poster Board II-570 Background: Trisomy 8 (+8) is one of the most common cytogenetical abnormality observed in acute myeloid leukemia (AML). The prognostic impact of +8 as sole aberration remains unclear and +8 may be classified either within intermediate- or high-risk subgroups. Recently, the prognostic impact of cytogenetic in AML has been refined by the identification of: 1) favorable genotypes in cytogenetically normal (CN) AML defined by the presence of either NPM1 gene mutation (NPM1m) or CEBPA gene mutation (CEBPAm) and the absence of FLT3 duplication (FLT3/ITD); 2) highly unfavorable AML with monosomal karyotype (MK). The aim of this study was to precise the prognostic impact of: 1) additional +8 in various cytogenetic risk subgroups; and 2) +8 as sole aberration when compared to different CN-AML genotypes. Patients: A total of 2087 patients with AML (AML-M3 excluded) were treated in the LAM-2001, LAM-SA-2002, ALFA-9802 and ALFA-9801 studies from the French AML Intergroup. After central review, cytogenetic analysis was considered successful in 1796 patients. Abnormalities were categorized according to the French AML Intergroup classification. All analysis (complete remission, CR; overall survival, OS; probability of continuous complete remission, %CCR) were stratified on studies. Results: +8 was present in 171/1796 (9.5%) with a similar incidence among the different cytogenetic subgroups: 22/243 fav-risk (9.1%), 99/1121 int-risk (8.8%), and 50/432 unfav-risk (11.6%). The incidence of +8 was significantly higher in MK-AML versus non MK-AML (30/223, 13.5%, p=.04). In none of these subgroups (fav, int, unfav, and MK), the presence of +8 was associated with a significantly different outcome (CR, OS, %CCR). When compared to patients with CN-AML, the 78 patients with +8 as sole anomaly had a similar age, a lower WBC (median WBC: 5 G/L vs 11.5 G/L, p=.004), a similar incidence of FLT3/ITD (22.2% vs 23.7%, 6/27 vs 101/426, p=.99), and a lower incidence of NPM1m (23.8% vs 46.5%, 5/21 vs 187/402, p=.05). In patients with +8 as sole anomaly, prognostic factors associated with a shorter OS were age (p=.01), high WBC (p=.01), and presence of +8 in all analyzed metaphases which was found in 1/3 of patients (p=.05). In those patients, when compared to CN-AML in general, CR rate was similar (88% vs 87%, p=.99), but %CCR and OS were shorter without, however, reaching significance (5y-%CCR: 31.8% vs 45.7%, p=.18). When compared to CN-AML patients with favorable genotypes (NPM1m or CEBPAm w/o FLT3/ITD), patients with +8 as sole anomaly had now a lower CR rate (87% vs 93%, p=.13) and significantly shorter %CCR and OS (5y-%CCR: 37.4% vs 57.8%, p=.05; 5y-OS 35.6% vs 59.0%, p=.05). Conversely, the prognosis of patients with +8 as sole anomaly appeared similar to that of patients with CN-AML w/o favorable genotypes (5y-OS: 32.6%). Conclusion: We report here the largest cohort of patients with +8. Additional +8 is equally distributed among cytogenetic risk subgroups and does not impact prognosis in each of these subgroups. Patients with AML with +8 as sole anomaly have an outcome comparable to that of CN-AML without favorable genotypes, suggesting that these patients should be managed similarly. Disclosures: No relevant conflicts of interest to declare.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2402-2402 ◽  
Author(s):  
Carmen Vicente ◽  
Ana Conchillo ◽  
Daphnie Pauwels ◽  
Iria Vazquez ◽  
Laura Garcia-Orti ◽  
...  

Abstract Abstract 2402 Poster Board II-379 The MYB proto-oncogene encodes a nuclear transcription factor with an essential role in proliferation, lineage commitment, and differentiation of hematopoietic progenitor cells. Proper levels of MYB are known to be important during hematopoietic cell development, and the Myb gene is a frequent target of retroviral insertions in myeloid, B- and T-cell leukemias in the mouse. Overexpression of MYB in T-acute lymphoblastic leukemia (T-ALL) causes a differentiation block of the T cells, and it has been shown that NOTCH1 mutation and MYB duplication cooperate in the pathogenesis of T-ALL. Our aim was to study the role of MYB in the pathogenesis of acute myeloid leukemia (AML), and to investigate its potential as a target for therapy. We functionally characterized MYB in 15 AML cell lines. Twelve of the 15 cell lines tested had MYB overexpression. Knockdown of MYB by siRNA in these cell lines caused decreased cell viability and proliferation, and reduced the clonogenic capacity, that could be explained in some cell lines by changes on the stage of cell differentiation. These results show that MYB overexpression is involved in the pathogenesis of AML. Moreover, knockdown of MYB in combination with common AML treatments (Idarubicin, Cytarabine and Sorafenib) had a strong synergistic effect on proliferation and viability of cells, suggesting that MYB could be a new target for therapy in AML. These observations prompted us to quantify MYB expression in a cohort of 159 patients with AML at diagnosis. We detected MYB overexpression in 14.5% (23/159) patients, with a higher prevalence within the intermediate prognosis group (17/83, 20.5%), particularly in patients with normal karyotype (NK) (14/62, 22.6%). Interestingly, 33% of patients without FLT-3 ITD and NPM1 mutations had MYB overexpression. To study the prognosis impact of MYB overexpression in AML, we performed a survival analysis in a preliminary series of 100 AML patients at diagnosis. As expected, significant differences in OS according to age, complete remission and cytogenetic prognostic group were found (p<0.01). MYB overexpression had no significant impact in the OS; however, this genetic marker allowed distinguishing a group of patients with a worse outcome within the group that did not get complete remission after treatment. Recently it has been described that MYB duplication causes elevated MYB expression in T-ALL; we detected duplication of MYB in 2 of 13 AML cell lines and in 2 patients with MYB overexpression (2/23, 8.6%). In conclusion, these results show that aberrant expression of MYB is involved in the activation of pathways responsible for the increased proliferative and clonogenic capacity that is characteristic of AML, independently of other genetic aberrations. Moreover, we show that MYB overexpression is a recurrent event in AML, especially in the subgroup of patients with NK, and that MYB could cooperate with other mutations in the leukemic transformation, as described previously in T-ALL. The synergistic effect of combined treatments with MYB knockdown, suggest that MYB silencing could be a new target for therapy in patients with AML and MYB overexpression. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 415-415 ◽  
Author(s):  
Verena I. Gaidzik ◽  
Richard F. Schlenk ◽  
Peter Paschka ◽  
Anja Stölzle ◽  
Andrea Corbacioglu ◽  
...  

Abstract Abstract 415 Background: Alteration of DNA methylation, a hallmark of epigenetic modification, is currently discussed as one important pathomechanism in leukemogenesis. Using a next-generation sequencing approach, a frameshift mutation of the gene encoding the DNA methyltransferase (DNMT3A) in an acute myeloid leukemia (AML) case was identified. DNMT3A catalyses the addition of a methyl group to the cytosine residue of CpG dinucleotides, thereby affecting promoter methylation status and gene expression. Subsequent sequencing analysis in an independent cohort of 288 AML patients (pts) revealed DNMT3A mutations (DNMT3Amut) in 22% of the pts; mutations were associated with intermediate-risk cytogenetics and poor outcome. Aims: To evaluate frequency and clinical impact of DNMT3Amut in pts with AML aged 18 to 61 years who were treated within AMLSG treatment trials AML HD98A (Schlenk et al., J Clin Oncol 2010;28:4642–8) and AMLSG 07–04 (NCT00151242). Methods: DNMT3A mutation analysis was performed in 1218 AML (HD98A, n=685; AMLSG 07–04, n=533; de novo AML, n=1102; s-AML, n=45; t-AML, n=69) using a DNA-based PCR assay for all coding exons (1 to 23) followed by direct sequencing. The median follow-up was 5.06 years. Results: DNMT3A mut were found with an overall frequency of 19.6% (239/1218); 189 mutations were located in the MTase domain clustering at amino acid R882 (79%). All but one mutation were heterozygous; only 4 cases had two mutations. DNMT3A sequence alterations included 17 frameshift, 4 nonsense, and 222 missense mutations. DNMT3A mut pts were significantly older (P=.01), more frequently females (P=.001), had higher white blood cell and platelet counts (both P<.0001), and higher bone marrow blasts percentage (P=.001). DNMT3Amut were associated with cytogenetically-normal AML (CN-AML, P<.0001), while DNMT3Amut were rare in favorable and adverse-risk karyotypes (P<.0001). Correlations with other molecular markers (NPM1, CEBPA, FLT3, IDH1/2, TET2, ASXL1) revealed a significant association with NPM1 (P<.0001), FLT3-ITD (P<.0001), and IDH1/2 (IDH1R132, P<.0001; IDH2R140, P=.0003; IDH2R172, P=.03) mutations, while co-occurrence of CEBPA (P=.02) and ASXL1 (P=.02) mutations was less frequent. DNMT3A mutational status did not impact complete remission (CR) rate, event-free (EFS) and relapse-free survival (RFS), neither in the whole cohort (P=.09, P=.98, P=.11; respectively) nor in the subgroup of CN-AML (P=.39, P=.79, P=.19, respectively). DNMT3Amut had a negative impact on overall survival (OS) in trend in the whole cohort (P=.07) and significantly in CN-AML (P=.02). In multivariable analyses, DNMT3Amut were in trend associated with a negative prognostic impact on OS (hazard ratio, 1.24; P=.06). In addition, we performed subgroup analyses according to (1) the NPM1 mutational status, and (2) the molecular risk groups of CN-AML (as defined by the European LeukemiaNet classification). DNMT3Amut did not impact OS in NPM1-mutated patients in the whole cohort as well as in CN-AML (P=.34; P=.22; respectively), while in NPM1-wildtype patients DNMT3Amut were associated with inferior OS in both, the whole cohort and in CN-AML (P=.001; P=.005; respectively). In molecular unfavorable CN-AML (NPM1-wildtype with or without FLT3-ITD, NPM1-mutated with FLT3-ITD, CEBPA-wildtype), DNMT3Amut were significantly associated with worse OS (P=.002) compared with DNMT3A-wildtype pts, even outweighing FLT3-ITD as an unfavorable prognostic marker. There was no effect of DNMT3Amut in molecular favorable-risk CN-AML. Conclusions: DNMT3A mutations are confirmed as frequent genetic aberrations in AML, associated with normal karyotype, NPM1, FLT3-ITD, and IDH1/2 mutations. DNMT3Amut predicts for inferior outcome in molecularly-defined subsets of AML, that is, NPM1-wildtype AML and molecular unfavorable CN-AML. As a single marker, DNMT3Amut only had a moderate effect on outcome. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2544-2544
Author(s):  
Xiuli Wang ◽  
Haiping Dai ◽  
Qian WANG ◽  
Qinrong Wang ◽  
Yang Xu ◽  
...  

Abstract Abstract 2544 Somatic mutation of the EZH2 gene is seen in myelodisplastic syndrome, myelofibrosis, and chronic myelomonocytic leukemia patients. The prevalence and prognostic impact of somatic mutations of EZH2 in patients with acute myelogenous leukemia (AML) remains unknown. In this study, we sought to determine the incidence and clinical implications of somatic EZH2 mutations in 714 patients with de novo AML by PCR amplification of the entire coding region followed by direct bidirectional DNA sequencing. EZH2 mutations were identified in 13/714 (1.8%) of AML patients and occurred almost exclusively in males (11/13, P=0.033). In univariate analysis, the presence of EZH2 mutations was significantly associated with lower blast percentage (21–30%) in bone marrow (P=0.0001) and −7/del(7q) (P=0.025). There was no difference in the incidence of mutations in 13 genes, including ASXL1, CBL, c-KIT, DNMT3A, FLT3, IDH1, IDH2, MLL, NPM1, NRAS, RUNX1, TET2, and WT1, between patients with and without EZH2 mutations. Complete remission, event-free survival or overall survival was similar between AML patients with and without EZH2 mutation (p>0.05). These results demonstrated EZH2 mutation as a recurrent genetic abnormality associated with lower blast percentage in BM and −7/del(7q) in de novo acute myeloid leukemia. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1492-1492
Author(s):  
Guadalupe Oñate ◽  
Ana Garrido ◽  
Jordi Esteve ◽  
Rosa Coll ◽  
Montserrat Arnan Sangerman ◽  
...  

Abstract Introduction The association of NPM1mut and FLT3-ITD in de novo acute myeloid leukemia (AML) with intermediate-risk cytogenetics has different prognostic impact depending on the FLT3 allelic burden. Previous studies published by our cooperative group showed that patients with de novo AML of intermediate-risk cytogenetics with NPM1mut and FLT3-ITD low ratio (<0.5, FLT3low) at diagnosis presented an overall survival and relapse rate similar to those with NPM1mut and FLT3wt. Therefore, in the CETLAM-2012 protocol, patients with FLT3low NPM1mut AML are not considered for allogenic hematopoietic stem cell transplant (allo-HSCT) in first complete remission (CR1). Recent studies suggest that the co-occurrence of DNMT3A mutation in FLT3-ITD NPM1mut AML patients confers a worse prognosis regardless of FLT3-ITD ratio. We analysed our data to determine whether these findings were confirmed in our cohort, specifically in the low FLT3-ITD ratio patients, since this could have therapeutic implications. Methods and patients A total of 163 patients with de novo AML, intermediate-risk cytogenetics and NPM1mut were analysed (median age 53 years (18-72); male:female 72:91 (0.79)). Eighty patients (49%) harboured an FLT3-ITD, with a high allelic ratio in 42 of 76 patients with available ITD/wt ratio (55%). They were included in the AML-2003 (n=49) and AML-2012 (n=114) CETLAM protocols. Proportion of patients undergoing alloHSCT in CR1 is detailed in table 1. Bone marrow samples from diagnosis were studied for DNMT3A mutations as previously described. The definition of complete remission (CR), overall survival (OS), leukemia-free survival (LFS) and risk of relapse (RR) followed recommended ELN criteria. The Kaplan-Meier method was used to estimate the distribution of LFS and OS, for RR cumulative incidence was used. Results Out of the 163 patients with AML of intermediate risk cytogenetics and NPM1mut, 78 presented DNMT3A mutations (48%). Of these, 62 (79%) presented mutations in codon R882 or corresponded to DNA insertions/deletions while 16 (21%) harboured missense mutations. Presence of DNMT3A mutation did not associate with FLT3-ITD (ITD/85 DNMT3Awt vs ITD/78 DNMT3Amut, p=0.394). In the entire cohort, 5-year OS, LFS and RR were 58±4.5%, 59±4.6% and 27±13.9%. FLT3-ITD ratio confirmed its prognostic impact when analysing FLT3wt (n=83) vs FLT3low (n=34) vs FLT3high (n=42) patients (5-year OS of 68±6% vs 62±8.7% vs 37±8.6%; p=0.002; and 5-year RR of 18±9.4% vs 27±16.1% vs 41±23.2%; p=0.023). On the contrary, DNMT3Amut did not exert any effect on overall outcome (5-yr OS DNMT3Awt vs DNMT3Amut 61±6.2% vs 55±6.2%; p=0.234) When DNTM3A mutational status was considered, the impact of FLT3-ITD on outcome was mitigated in wild-type DNMT3A population. Thus, we found that DNMT3Awt patients presented no statistical differences in OS according to FLT3 mutational status or ratio: FLT3wt (n=46) vs FLT3-ITD (n=39) was 67±8.5% vs 57±8.2%; p=0.122, whereas FLT3wt (n=46) vs FLT3low (n=18) vs. FLT3high (n=19) was 67±8.5% vs. 66±11.5% vs 46±11.8%; p=0.088 (image 1A).This was also seen in relation to LFS and RR according to FLT3 ratio: 5-yr LFS of FLT3wt vs FLT3low vs FLT3high was 72±7.9% vs 61±12.6% vs 51±13.4%; p=0.244 and 5-year RR of the same groups: 19±8.8% vs 26±12.5% vs 27±21.9%; p=0.724 (image 2A). In the DNMT3Amut group, patients with FLT3-ITD (n=41) presented shorter OS than those with FLT3wt (n=37) with an OS of 37±10.7% vs 69±7.8%; p=0.028. When FLT3 ratio was considered, FLT3wt (n=37) vs FLT3low (n=16) vs FLT3high (n=23) showed an OS of 69±7.8% vs. 58±13.2% vs 27±13.1%; p=0.038 (image 1B). Similar results were seen in LFS according to FLT3 ratio (FLT3wt (n=29) vs FLT3low (n=16) vs FLT3high (n=20) 71±8.6% vs 53±12.9% vs 18±13.8%; p=0.012). Finally, we observed significant differences in the 5-year RR when considering DNMT3Amut patients in relation to FLT3 ratio (FLT3wt vs FLT3low vs FLT3high 18±10.6% vs 27±20% vs 54±28.8%; p=0.021)(image 2B). Conclusions In this study, patients with NPM1mut and FLT3-ITDlow presented a similar outcome to patients with NPM1mut and FLT3wt regardless of DNMT3A mutational status. These results support the modification of alloHCST policy in CR1 in CETLAM-2012, which do not consider alloHSCT for patients with FLT3low. On the other hand, concurrence of DNMT3A mutation may have an added negative effect in patients with NPM1mut and FLT3-ITDhigh, which should be further confirmed in larger studies. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 1003-1003 ◽  
Author(s):  
Isabel Granada ◽  
Salut Brunet ◽  
Montserrat Hoyos ◽  
Dolors Costa ◽  
Anna Aventín ◽  
...  

Abstract Abstract 1003 Poster Board I-25 Introduction: Recently, the cooperative group HOVON-SAKK has refined the prognostic impact of cytogenetic abnormalities in acute myeloid leukemia (AML) by introducing the concept of monosomal karyotype (MK). This consists of ≥ 2 autosomal monosomies or one autosomal monosomy in addition to a structural alteration. In their experience, MK would explain the poor prognosis of AML with a complex karyotype. Objective: To investigate the prognostic impact of MK in patients with primary (de novo) AML enrolled in the Spanish CETLAM group protocols (AML 94/99/03). Also, to determine whether considering MK added predictive value to the cytogenetic classification of the Medical Research Council (MRC). Methods: Retrospective analysis of data from 1149 AML patients. Chromosomal formula was centrally reviewed with karyotypes being classified by the presence of MK and allocated into the MRC risk categories. Complete remission (CR) rate, disease-free survival (DFS) and overall survival (OS) were calculated. Results: The karyotype was assessable in 904 (79%) of the 1149 cases. In 145 of the 904 cases (16%), abnormalities involving CBF gene were detected and in 437 (48%) the karyotype was normal (NK). In 253 (28%) additional patients the karyotype was not monosomal; of them, 61 (24%) belonged to the unfavorable MRC with 17 cases harboring a complex karyotype ≥ 5 abnormalities, 7 cases with rearrangements 3q, 13 cases with -7, 9 cases with 5q abnormalities and 16 cases with t(6;9)). The remaining 69 (7.7%) patients had a MK; of them, 59 (85.5%) were from the unfavorable MRC category and included 43 cases with complex karyotype ≥ 5 abnormalities, 6 cases with rearrangements 3q, 5 cases with -7, 5 cases with alterations of 5q). The following table summarizes the results in terms of CR rate, DFS and OS: Conclusions: The addition of MK to the MRC cytogenetic classification refines the prognostic prediction. In our series, the dismal outcome of patients with MK is confirmed; these patients had worse prognosis than those with adverse cytogenetics without MK. Alternative treatment strategies are mandatory for MK+ patients. Supported in part by grants: GR1-01075, ECO07/90065, PI080672 and RD06/0020/0101. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 2586-2586
Author(s):  
Juana Serrano-Lopez ◽  
Josefina Serrano ◽  
Joaquín Sanchez-Garcia ◽  
Noemi Fernandez-Escalada ◽  
Maria del Carmen Martinez-Losada ◽  
...  

Abstract Abstract 2586 Introduction: Acute Myeloid Leukemia (AML) is a heterogeneous disorder arising from a clonal expansion of Leukemic Stem Cell (LSC). The characterization of LSC is crucial because it is resistant to conventional chemotherapy and is ultimately responsible for leukemic relapses. The LSC in AML is a phenotypically heterogeneous population (CD34+CD38-, CLL1 +, CD96 +…). In this sense, “Side Population” cells (SPHo342Low) are considered to be a type of stem cells that can self-renew and differentiate into tissues. SP are characterized by their ability to efflux the vital dye Hoechst 33342 through the drug ABCG2 pump. SPHo342Low cells have been described in many types of solid tumors and AML as potential LSC. The objective in this study is to analyze the frequency of SPHo342Low in AML, their phenotype and the possible prognostic impact on outcomes. Patients and Methods: Bone marrow samples (BM) obtained from 57 patients (median age 58 years, range: 4–82), diagnosed with AML between Mar-07 to Mar-12, were included. Distribution of cytogenetic risk groups was: Favorable (12.5%), Intermediate (60.7%) and Unfavorable (26.8%). NPM1mut was present in 11 cases and FLT3-ITD in 6 cases. Prior MDS was present in 10 cases. After achieving complete remission (CR) with conventional chemotherapy, allogeneic or autologous stem cell transplantation was performed in 17 and 12 patients respectively, according to individual risk and availability of donor. Eleven frail patients received as front-line, low intensity therapy with Azacytidine. We detected LSC, SPHo342Low in marrow MNCs obtained at diagnosis (N=40), at morphologic complete remission (CR) (N=21) or at relapsed / resistant (N=16) disease. For detection, 2×10(6) MNC/ml were resuspended in HBSS medium with 5 ug/ml of Ho342 dye and CD45-FITC, CD34-PE Mn-Abs, analyzing at least 1×105 viable cells in UV laser FACSVantage cytometer with the combination of filters BP 670/40 for emission in red and BP 450/30 for the blue emission. We verified SP region by inhibiting ABCG2 pump with Verapamil (50μM/mL). As controls we analyzed MNCs from BM aspirates from healthy donors (N=5). Results: In all BM samples from healthy donors, SPHo342Low population was detected accounting for 0.5% (range: 0.1 to 0.9%) and it was CD34negCD45neg phenotype in 80% of cases. SPHo342Low cells were detected in 23/40 cases (57.5%) of samples from AML diagnosis with a median of 0.08% (range 0.01–2.3%). Phenotype of SPHo342Low cells at diagnosis was CD34+CD45+/− in 36% of cases. The presence of SPHo342Low cells presented in AML at diagnosis did not statistically correlate with any prognostic clinical variables such as age, cytogenetic-molecular risk or prior MDS. Interestingly, the detection of LSC SPHo342Low at diagnosis was statistically associated to the presence of >0.1% of CD34+CD38- AML cells (P=0,03). In BM samples obtained from AML patients in CR, SPHo342Low cells were detected in 17/21 (81.0%) with a median of 0.17% (range: 0.1 to 0.76%), with a phenotype mostly CD34 negative. In BM samples obtained from AML patients in relapsed/refractory situation, SPHo342Low cells were detected in 14/16 (87.5%) with a median of 0.22% (range: 0.2 to 0.91%) with a phenotype of CD34+ CD45+/− in 33% of cases. Interestingly, patients who did not achieve CR, have a significantly higher percentage of SPHo342Low at diagnosis (0.42% vs. 0.06%, P = 0.044) as well as those who need more than one cycle to achieve CR (0.52% vs. 0.07%, P = 0.04). Moreover, for those patients achieving CR, persistence of Minimal Residual Disease (MRD+) was associated to a higher percentage of SPHo342Low at diagnosis (0.28% vs. 0.05%, P = 0.021). Likewise, Relapse-free survival (RFS) was significantly higher in AML patients lacking SPHo342Low at diagnosis (70 ± 18.2% vs. 43.3 ± 17.6%, P = 0.0324, Log rank test). Conclusions: Detection of LSC SPHo342Low+CD34+CD45+/− phenotype in AML at diagnosis is a common finding that is associated with increased resistance to achieve CR, clearance of MRD and lower RFS. During progression of disease this SPHo342Low+ population increases and maintains CD34+CD45neg phenotype. BM samples obtained from AML patients at CR were SPHo342Low+ CD34negCD45+/− phenotype which can be considered responsible for normal hematopoietic regeneration. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 879-879
Author(s):  
Raffaella Pippa ◽  
Ana Dominguez ◽  
Nerea Marcotegui ◽  
Raquel Malumbres ◽  
Elizabeth Guruceaga ◽  
...  

Abstract INTRODUCTION. The protein SET (I2PP2A), a potent protein phosphatase 2A (PP2A) inhibitor, has been implicated in many cell processes such as DNA replication, chromatin remodeling and gene transcription, differentiation, migration, and cell-cycle regulation. In fact, SET has been described as an oncogene that regulates important signaling pathways. Our group reported that PP2A inhibition is a common event in AML, and that SET is overexpressed in 28% of acute myeloid leukemia (AML) cases, where it is associated with short overall survival. Moreover, the anti-leukemic effects of the FTY720 and OP449 PP2A-activating drugs in AML cells depend on interaction/sequestration of SET. However, despite the importance of SET overexpression and its prognostic impact in both hematological and solid tumors, there are few data about the mechanisms involved in its regulation. AIM. To characterize the functional promoter region of the SET gene, and to identify transcription factors (TFs) involved in its regulation. RESULTS. Luciferase reporter assays with five truncatedconstructs allowed us to determine a 163bp-region as the minimal promoter region of SET that contains consensus sites for several TFs. Chromatin immunoprecipitation (ChIP) assays confirmed the binding of RUNX1, GATA2, MYC, and SP1. RUNX1 and GATA2 are two essential TFs in hematopoiesis, and localized on the SET promoter when the acetylation state of both histone H3 and H4 and the tri-methylation on H3K4 is high, confirming that they both could act as positive regulators of SET transcription. In silico analysis in large series of adult patient samples with de novo AML recently published by The Cancer Genome Atlas Research Network showed a significant positive correlation between SET and RUNX1 and GATA2 at mRNA level. Furthermore, knockdown of RUNX1 and/or GATA2 triggered SET downregulation, whereas only a simultaneous overexpression of these two TFs caused a significant up-regulation of SET. Interestingly, RUNX1 interacts with GATA2 in both HL-60 and HEL cell lines. Moreover, we found that SP1 is also part of this transcription complex. Altogether, these results show that RUNX1 and GATA2, together with SP1, regulate the transcription of the SET gene. CONCLUSIONS We have defined the minimal promoter region of the SET gene, and have demonstrated that RUNX1 and GATA2 regulate its expression in AML. Moreover, our functional studies demonstrate that RUNX1 and GATA2 form a complex with SP1 that activates the transcription of SET in AML cells. This study opens new directions to further understand the mechanisms of SET overexpressing leukemias. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4891-4891
Author(s):  
Igala Marielle ◽  
Mouna Lamchaheb ◽  
Nisrine Khoubila ◽  
Siham Cherkaoui ◽  
Bouchra Oukache ◽  
...  

Abstract Introduction: Treatment of Acute Myeloid Leukemia (AML) with in developing countries is challenging. In Morocco, the major causes of therapy failure are delay in diagnosis, early (prior to start of therapy) and induction deaths, induction failures and abandonment of therapy. Improvement of supportive care with particular focus on prevention and management of infection and improved transfusion support is crucial for better overall outcome. Aim of the study: To evaluate the preliminary results (Complete remission, OS and EFS) in children and young adults with favorable risk group AML treated in a single center with AML MA 2011 protocol. Patients and methods: From January 2011 to December 2014, a uniform treatment protocol was conducted to treat patients with age ≤ 30 years with de novo AML with favorable risk group. The diagnosis was done according to FAB classification, MPO done systematically. Karyotype was performed on marrow sample (20 metaphases analyze at least), R banding technique. Patients with hyperleukocytosis (WBC≥ 50G/L) received as a pre-phase 4 days of hydroxyurea to 50mg/kg/day then 2 inductions and 3 consolidations. The two courses of induction associated Cytarabine (100mg/m² q 12h (day 1-10)), Daunorubicin (50 mg/m² (day 2, 4, 6) for the first course, on days 1, 3, 5 for the second course) and etoposide (100mg/m² only at second course of induction). The consolidation included Cytarabine (3g/m²q 12h (day1-3) for first and second course and 1 g/m² (day1-3) on third course) plus Daunorubicin (30mg/m² (day 3-4 and day 1-3) at the first and third consolidation. L-Asparaginase 6000UI/m² on day 4 was give at second consolidation. Patients received CNS prophylaxis. The supportive care consisted of transfusion, antibiotic and patient and family education by hygiene team. Results: 39/159 patients (24.5%) had a favorable prognosis. They were 13 female and 26 male (Male/Female ratio of 2) with a median age of 21 years and the peak frequency was between 20-30 years (21 patients or 53.8%). Two groups were identified. (Table 1) The means WBC were 39.741 G/L (1.134-425.000G/L) and more than 50 G/L for 17 patients. t(8; 21) represented 71.8% of karyotype and was associated 14 times with other abnormalities: 8 loss of sex chromosome (6 -Y and -X 2), 2 deletions, 2 trisomy and 2 add. Inv16 or t (16; 16), 28.2% of case, was associated with a deletion once and once with trisomy. (Table 1) Molecular biology carried 7 times was positive in 4 cases all AML-ETO. Three patients died before treatment, two in hospital by septic shock (1), subarachnoid hemorrhage (1) and one at home. 36/39 patients were evaluable for the protocol. 17 patients with WBC > 50G/L received hydroxyurea prior to chemotherapy with good response for 16 (94.1%) and 1 (5.9%) death. The median average time from start of treatment was 15 days with a range of 1-52 days. After the two inductions 26 (74.3%) obtained a complete remission, 2 (5.7%) were in failure, and 7 (20%) died in hospitalization during induction 1. The cause of death was: 2 hemorrhage, 3 infections, 1 pulmonary embolism and 1 patient died at home. Conclusion: Therapeutic results are yet far from satisfactory. Complete remission could be improved with reduction of infection toxic deaths. Improvement of supportive care therapy may allow treating patients with intensified treatment with better outcome. Hydroxyurea is efficient to reduce WBC and for best conditions to initiate induction therapy. Table 1. Patient's characteristics All patients Group 1(age ≤15years) Group 2(age≥16 years) Number (%) Median age (Years) 39 (100%) 21 9 (23%) 10 30 (77%) 24 Male/Female 2 3.5 1.7 WBC>50000 (G/L) 17 2 7 FAB M1/M2/M4/M4Eo/other Immunophenotype 12/19/2/4/2 28 (71.8%) 1/7/1/0/0 7 (25%) 11/12/1/4/2 21 (75%) t(8 ;21) 28 (71.8%) 8 (88.9%) 20(66.7%) t(8 ;21)+ other anomalies 14 (50%) 5 (62.5%) 9 (45%) Inv 16 or t(16 ;16)Inv16 or t(16 ;16) + other anomaliesTreatmentComplete remission DeathFailureCauses of death infection/Hemorrhage/otherOSES 11 (28.2%) 2 (18.2%) 36*(92.3%) 26 (72.2%) 7 (18%) 2 2/3/2 51% 30.9% 1 (11.1%) 1 (100%) 9 (100%) 8 (88.9%) 1 (11.1%) 0 0/1/0 10 (33.3%) 1 (10%) 26 (86.7%) 18 (69.2%) 6 (23.1%) 2 (7.7%) 2/2/2 *One death after prephase Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2002 ◽  
Vol 100 (1) ◽  
pp. 29-35 ◽  
Author(s):  
Sandra R. Wolman ◽  
Holly Gundacker ◽  
Frederick R. Appelbaum ◽  
Marilyn L. Slovak

Abstract The prognostic impact of trisomy 8, alone or with other clonal aberrations, was evaluated in 849 patients with previously untreated acute myeloid leukemia (AML) who were registered to 5 Southwest Oncology Group trials. At presentation, 108 (12.7%) patients had +8 in their karyotypes, including 43 (5.1%) patients with +8 as the sole aberration; 307 (36.2%) were normal, and 434 (51.1%) had other cytogenetic abnormalities. Patients with +8 were slightly older (P = .033), had lower WBC (P = .011), and had lower percentages of peripheral blasts (P = .0004) than the patients without +8. Median survival time for all patients with +8 was 9.9 months (95% CI, 6.5-12.5), similar to that of “unfavorable” cytogenetics risk groups (8.3 months; 95% CI, 6.8-9.5.) Patients with +8 had significantly lower peripheral blasts (P = .0002), WBC (P &lt; .0001) counts, and decreased overall survival (OS) than patients with normal cytogenetics (9.9 months vs 15.4 months; P = .006). However, survival of patients with +8 as the sole aberration did not differ significantly from those with normal cytogenetics (P = .36). Thus, the trisomy 8 group as a whole had poor survival, which was largely attributable to worsened outcomes among patients whose trisomy 8 was associated with other unfavorable cytogenetic abnormalities.


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