The Clinical Features and Prognostic Impact of PRDM16 gene Expression in Adult Acute Myeloid Leukemia

Abstract Background Acute myeloid leukemia (AML) is a complex disease caused by various genetic alterations. Some prognosis-associated cytogenetic aberrations or gene mutations such as FLT3-internal tandem duplication (ITD), t(8;21)(q22;q22)/RUNX1-RUNX1T1, and inv(16)(p13q22)/CBFB-MYH11 have been found and used to stratify the risk. Numerous gene mutations have been implicated in the pathogenesis of AML, including mutations of DNMT3A, IDH1/2, TET2 and EZH2 in addition to RAS, KIT, NPM1, CEBPA and FLT3in the recent development of massively parallel sequencing technologies. However, even after incorporating these molecular markers, the prognosis is unclear in a subset of AML patients. Recently, NUP98-NSD1 fusion gene was identified as a poor prognostic factor for AML. We have reported that all pediatric AML patients with NUP98-NSD1 fusion showed high expression of the PR domain containing 16 (PRDM16; also known as MEL1) gene, which is a zinc finger transcription factor located near the breakpoint at 1p36. PRDM16 is highly homologous to MDS1/EVI1, which is an alternatively spliced transcript of EVI1. Furthermore, PRDM16 is essential for hematopoietic stem cell maintenance and remarkable as a candidate gene to induce leukemogenesis. Recent reports revealed that high PRDM16 expression was a significant marker to predict poor prognosis in pediatric AML. However, the significance of PRDM16 expression is unclear in adult AML patients. Methods A total of 151 adult AML patients (136 patients with de novo AML and 15 patients with relapsed AML) were analyzed. They were referred to our institution between 2004 and 2015 and our collaborating center between 1996 and 2013. The median length of follow-up for censored patients was 30.6 months. Quantitative RT-PCR analysis was performed using the 7900HT Fast Real Time PCR System with TaqMan Gene Expression Master Mix and TaqMan Gene Expression Assay. In addition to PRDM16, ABL1 was also evaluated as a control gene. We investigated the correlations between PRDM16 gene expression and other genetic alterations, such as FLT3-ITD, NPM1, and DNMT3A, and clarified the prognostic impact of PRDM16 expression in adult AML patients. Mutation analyses were performed by direct sequence analysis, Mutation Biased PCR, and the next-generation sequencer Ion PGM. Results PRDM16 overexpression was identified in 29% (44/151) of adult AML patients. High PRDM16 expression correlated with higher white blood cell counts in peripheral blood and higher blast ratio in bone marrow at diagnosis; higher coincidence of mutation in NPM1 (P = 0.003) and DNMT3A (P = 0.009); and lower coincidence of t(8;21) (P = 0.010), low-risk group (P = 0.008), and mutation in BCOR (P = 0.049). Conversely, there were no significant differences in age at diagnosis and sex distribution. Patients with high PRDM16 expression tended to be low frequency in M2 (P = 0.081) subtype, and the remaining subtype had no significant differences between high and low PRDM16 expression. Remarkably, PRDM16 overexpression patients were frequently observed in non-complete remission (55.8% vs. 26.3%, P = 0.001). Patients with high PRDM16 expression tended to have a cumulative incidence of FLT3-ITD (37% vs. 21%, P = 0.089) and MLL-PTD (15% vs. 5%, P = 0.121). We analyzed the prognosis of 139 patients who were traceable. The overall survival (OS) and median survival time (MST) of patients with high PRDM16 expression were significantly worse than those of patients with low expression (5-year OS, 17% vs. 32%; MST, 287 days vs. 673 days; P = 0.004). This trend was also significant among patients aged <65 years (5-year OS, 25% vs. 48%; MST, 361 days vs. 1565 days, P = 0.013). Moreover, high PRDM16 expression was a significant prognostic factor for FLT3-ITD negative patients aged < 65 years in the intermediate cytogenetic risk group (5-year OS, 29% vs. 58%; MST, 215 days vs. undefined; P = 0.032). Conclusions We investigated the correlations among PRDM16 expression, clinical features, and other genetic alterations to reveal clinical and prognostic significance. High PRDM16 expression was independently associated with non-CR and adverse outcomes in adult AML patients, as well as pediatric AML patients. Our finding indicated that the same pathogenesis may exist in both adult and pediatric AML patients with respect to PRDM16 expression, and measuring PRDM16 expression was a powerful tool to predict the prognosis of adult AML patients. Disclosures Inokuchi: Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria; Celgene: Honoraria; Pfizer: Honoraria.

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Role of Gene Mutations in Adult Acute Myeloid Leukemia Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation.

Blood ◽

10.1182/blood.v114.22.3373.3373 ◽

2009 ◽

Vol 114 (22) ◽

pp. 3373-3373

Author(s):

Sheng-Chieh Chou ◽

Jih-Luh Tang ◽

Liang-In Lin ◽

Hsin-An Hou ◽

Chien-Yuan Chen ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Stem Cell ◽

Myeloid Leukemia ◽

Gene Mutations ◽

Genetic Alterations ◽

Prognostic Impact ◽

Hematopoietic Stem ◽

Wbc Count ◽

Acute Myeloid

Abstract Abstract 3373 Poster Board III-261 Purpose Several gene mutations had been found to have clinical implications in patients with acute myeloid leukemia (AML), especially in those with normal karyotype. However, the role of such gene mutations for AML patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT) was unclear and inconclusive. We retrospectively evaluated the prognostic impact of 8 gene mutations in adult AML patients undergoing allo-HSCT. Materials & Methods From 1995 to 2007, a total of 463 consecutive adult patients with de novo non-M3 AML had comprehensive gene mutation analyses at the National Taiwan University Hospital. Three hundred and twenty five patients who received conventional induction chemotherapy were enrolled in this study. Those who received only low dose chemotherapy or palliative treatment were excluded. The genetic alterations analyzed included NPM1, FLT3/ITD, FLT3/TKD, CEBPA, AML1/RUNX1, RAS, MLL/PTD, and WT1. The clinical implication of these genetic alterations in the patients receiving allo-HSCT was analyzed, and the result was compared with that in patients without allo-HSCT. Results The clinical characteristics in the patients receiving allo-HSCT (n=100) and those without (n=225) were similar with the exception of age, being younger in the former group (35.4 years vs. 49.5 years p<0.001). In univariate analysis, older age (Age > 45 years), higher initial WBC count (WBC>50K/μL), elevated LDH level, unfavorable karyotype, FLT3/ITD, mutations of AML1/RUNX1 were significantly associated with poorer overall survival (OS) in patients not receiving allo-HSCT; While NPM1mut/FLT3ITDneg and CEBPA mutations served as significantly good prognostic indicators. In multivariate analysis, age, WBC count, karyotype, FLT3/ITD, AML1/RUNX1, CEBPA and NPM1mut/FLT3ITDneg remained to be independent prognostic factors in non-allo-HSCT patients. However, in patients receiving allo-HSCT, only unfavorable karyotype and disease status (refractory or remission) at the time of transplantation were associated with poorer OS both in univariate and multivariate analyses. The similar prognostic impact of FLT3/ITD, CEBPA, AML1/RUNX1 and NPM1 on OS was not seen in patients receiving allo-HSCT. Furthermore, in contrast to its poor prognostic impact in non-allo-HSCT patients, mutation of AML1/RUNX1 was a significant good prognostic factor for relapse free survival (p=0.046), although not for OS, in allo-HSCT group. Conclusion FLT3/ITD, mutations of AML1/RUNX1, CEBPA and NPM1 have great prognostic implication for OS in AML patients not receiving allo-HSCT. However, their impact on OS is ameliorated in patients receiving allo-HSCT. The results need to be confirmed by further studies on more patients. Disclosures: No relevant conflicts of interest to declare.

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Heterogeneity in Infants with Acute Myeloid Leukemia: Retrospective Analysis of a Japanese Nationwide Survey

Blood ◽

10.1182/blood.v118.21.1477.1477 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1477-1477

Author(s):

Akira Shimada ◽

Daisuke Tomizawa ◽

Akitoshi Kinoshita ◽

Kazuko Hamamoto ◽

Ichiro Tsukimoto ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Survival Rate ◽

Retrospective Analysis ◽

Myeloid Leukemia ◽

Genetic Alterations ◽

Fish Analysis ◽

Prognostic Impact ◽

Hematopoietic Stem ◽

Pediatric Aml ◽

Acute Myeloid

Abstract Abstract 1477 Introduction: When compared to older patients, infants with acute leukemia exhibit distinct cytogenetic features, such as higher prevalence of MLL gene rearrangement (MLL-R), and are known to have higher vulnerability to intensive cytotoxic therapy, such as hematopoietic stem cell transplantation. In contrast to acute lymphoblastic leukemia (ALL), there have been few reports on acute myeloid leukemia (AML) in infants. To develop more appropriate therapeutic strategies for infants with AML, it is necessary to elucidate the distinct clinical features of this subgroup. We therefore performed a retrospective analysis on infant AML in Japan. Patients: Infants with AML, aged less than 1 year at diagnosis, registered in any of the 6 Japanese AML clinical trials between 1991 and 2010 (TCCSG M91-13, TCCSG M96-14, AML99, CCLSG9805, CCLSG9805RE, and JPLSG AML-05) were included in this study. Patients with Down syndrome were excluded. Results: A total of 122 infant AML patients were included in the present analysis, which comprised approximately 10% of all pediatric AML patients. The most frequent FAB classification type was M5 (28.7%), followed by M7 (22.9%) and M4 (10.8%). About 30% of patients had 11q23 abnormalities/MLL -R, but there was no impact on prognosis. Several cases with normal karyotype were revealed to be MLL -R on FISH analysis or on MLL -fusion chimeric transcript analysis by RT-PCR. t(8;21), inv(16) and t(15;17) cases were very rare among the infant cohorts. Furthermore, 7.8% had t(1;22)(p13;q13), and 2.5% had t(7;12)(q36;p13). Genetic mutation results could be obtained in 11 cases in the AML99 study; only one case each was confirmed to have NRAS, KRAS or KIT gene mutation. No cases with FLT3-ITD were detected among the 11 cases in the AML99 or the 44 cases in the AML-05 study. Survival rate varied based on treatment received; 5-year OS rate was 58.3% to 71.4%, and 5-year EFS rate was 49.4% to 64.2%. Discussion: Survival rate in infant AML was identical to that in older pediatric AML. However, there was a possible underestimation of MLL -R patients based on sole chromosome analysis; the prevalence of MLL -R was less than 50% in infant AML patients, without any prognostic impact. Other well-known genetic alterations in pediatric AML also had no effect on outcome of infant AML. Infant AML is a heterogeneous subgroup of pediatric AML, and further studies, as well as novel biomarkers, will be necessary to fully understand its biology. Disclosures: No relevant conflicts of interest to declare.

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Mutational landscape and clinical outcome of patients with de novo acute myeloid leukemia and rearrangements involving 11q23/KMT2A

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2014732117 ◽

2020 ◽

Vol 117 (42) ◽

pp. 26340-26346

Author(s):

Marius Bill ◽

Krzysztof Mrózek ◽

Jessica Kohlschmidt ◽

Ann-Kathrin Eisfeld ◽

Christopher J. Walker ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Risk Group ◽

Gene Mutations ◽

Specific Gene ◽

Prognostic Impact ◽

Fusion Partner ◽

Mutational Landscape ◽

Mutational Status ◽

Acute Myeloid

Balanced rearrangements involving theKMT2Agene, located at 11q23, are among the most frequent chromosome aberrations in acute myeloid leukemia (AML). Because of numerous fusion partners, the mutational landscape and prognostic impact of specific 11q23/KMT2Arearrangements are not fully understood. We analyzed clinical features of 172 adults with AML and recurrent 11q23/KMT2Arearrangements, 141 of whom had outcome data available. We compared outcomes of these patients with outcomes of 1,097 patients without an 11q23/KMT2Arearrangement categorized according to the 2017 European LeukemiaNet (ELN) classification. Using targeted next-generation sequencing, we investigated the mutational status of 81 leukemia/cancer-associated genes in 96 patients with 11q23/KMT2Arearrangements with material for molecular studies available. Patients with 11q23/KMT2Arearrangements had a low number of additional gene mutations (median, 1; range 0 to 6), which involved the RAS pathway (KRAS,NRAS, andPTPN11) in 32% of patients.KRASmutations occurred more often in patients with t(6;11)(q27;q23)/KMT2A-AFDNcompared with patients with the other 11q23/KMT2Asubsets. Specific gene mutations were too infrequent in patients with specific 11q23/KMT2Arearrangements to assess their associations with outcomes. We demonstrate that younger (age <60 y) patients with t(9;11)(p22;q23)/KMT2A-MLLT3had better outcomes than patients with other 11q23/KMT2Arearrangements and those without 11q23/KMT2Arearrangements classified in the 2017 ELN intermediate-risk group. Conversely, outcomes of older patients (age ≥60 y) with t(9;11)(p22;q23) were poor and comparable to those of the ELN adverse-risk group patients. Our study shows that patients with an 11q23/KMT2Arearrangement have distinct mutational patterns and outcomes depending on the fusion partner.

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Chromosome Aberrations, Gene Mutations and Expression Changes, and Prognosis in Adult Acute Myeloid Leukemia

Hematology ◽

10.1182/asheducation-2006.1.169 ◽

2006 ◽

Vol 2006 (1) ◽

pp. 169-177 ◽

Cited By ~ 75

Author(s):

Krzysztof Mrózek ◽

Clara D. Bloomfield

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Chromosome Aberrations ◽

Myeloid Leukemia ◽

Molecular Genetic ◽

Prognostic Significance ◽

Gene Mutations ◽

Normal Karyotype ◽

Genetic Alterations ◽

Acute Myeloid

Abstract Pretreatment clinical features and prognosis of patients with acute myeloid leukemia (AML) are strongly influenced by acquired genetic alterations in leukemic cells, which include microscopically detectable chromosome aberrations and, increasingly, submicroscopic gene mutations and changes in gene expression. Cytogenetic findings separate AML patients into three broad prognostic categories: favorable, intermediate and adverse. The cytogenetic-risk classifications differ somewhat for younger adult patients and those aged 60 years or older. In many instances, patients with specific cytogenetic findings, e.g., those with a normal karyotype or those with either t(8;21)(q22;q22) or inv(16)(p13q22)/t(16;16)(p13;q22) [collectively referred to as core-binding factor (CBF) AML] can be further subdivided into prognostic categories based on the presence or absence of particular gene mutations or changes in gene expression. Importantly, many of these molecular genetic alterations constitute potential targets for risk-adapted therapies. In this article, we briefly review major cytogenetic prognostic categories and discuss molecular genetic findings of prognostic significance in two of the largest cytogenetic groups of patients with AML, namely AML with a normal karyotype and CBF AML.

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Nucleophosmin Gene Mutations Identify a Favorable Risk Group in Childhood Acute Myeloid Leukemia with a Normal Karyotype.

Blood ◽

10.1182/blood.v110.11.366.366 ◽

2007 ◽

Vol 110 (11) ◽

pp. 366-366

Author(s):

Iris H. Hollink ◽

Christian M. Zwaan ◽

Marry M. van den Heuvel-Eibrink ◽

Martin Zimmerman ◽

Susan Arentsen-Peters ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Gene Mutations ◽

Normal Karyotype ◽

Type A ◽

Prognostic Impact ◽

Wild Type ◽

Molecular Abnormalities ◽

Pediatric Aml ◽

Acute Myeloid

Abstract Exon 12 gene mutations in nucleophosmin (NPM1) were recently discovered in approximately 30% of adult acute myeloid leukemia (AML) samples, and cluster in the normal karyotype subgroup (NK-AML). NPM1-mutated adult NK-AML has a favorable outcome (pOS in the 40-50% range), but in case a FLT3 internal tandem duplication (FLT3/ITD) is also present outcome is worse with 25–30% pOS. In pediatric AML, NPM1 mutations are less frequent (6–8%; Cazzaniga, Blood 2005 & Brown, Blood 2007). No studies have specifically addressed pediatric NK-AML, a subgroup lacking favorable prognostic cytogenetic aberrations and therefore mostly stratified in the intermediate risk arm of pediatric AML treatment protocols. We screened 292 newly diagnosed AML samples, and detected NPM1 mutations in 25 cases (8.6%). We also screened 46 initial diagnosis-relapse pairs, and no clonal instability was observed, which suggests that NPM1 mutations may be used for minimal residual disease detection. In contrast to adults, where type A mutations (TCTG-insertion) are most frequent (80%), in our cohort type B (CATG-insertion) mutations were found in 39% and type A in 23%. In the NK-AML cohort (n=98), 20% was NPM1-mutated, which was age dependent: <3 years, 0%; 3–10 years, 19%; >10 years, 29% (p=0.04). None of the 10 FAB M5 cases was NPM1 mutated (p=0.09). NPM1 mutations had an independent favorable prognostic impact on outcome in patients with NK-AML (5-year pEFS 77% vs. 41% for wild type patients; p=0.003), irrespective of FLT3 mutational status. In fact, NPM1-mutated patients with a FLT3/ITD did better than patients without an ITD, although this was not statistically significant (5-year pEFS 90% vs. 63%, respectively; p=0.48). In NK-AML without NPM1 mutations, patients with FLT3/ITD positive AML did significantly worse than wild type FLT3 AML patients (5-year pEFS 18% vs. 52%, p=0.002). The differential prognostic impact of FLT3/ITD between the NPM1-mutated vs. the wild type patients was not caused by differences in the FLT3/ITD allelic ratio or ITD length, nor was there a relationship with the type of NPM1 mutations. Multivariate analysis, including age, white blood cell count, NPM1 and FLT3 status and stem cell transplantation as time-dependent co-variable, showed that only NPM1 mutations had independent prognostic significance for pEFS (RR 0.34, p=0.02). We conclude that the incidence of NPM1 mutations increases with age, and that NPM1 mutations define a subgroup with favorable prognosis in pediatric NK-AML. Our data suggest that these molecular abnormalities allow stratification of children with NK-AML. However, different from adult NK-AML, we observed that all children with NPM1 mutations did well, irrespective of FLT3 status. Therefore, treatment in the ‘good risk’ arm should be considered for children with NPM1-mutated NK-AML.

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Clinical relevance of mutations and gene-expression changes in adult acute myeloid leukemia with normal cytogenetics: are we ready for a prognostically prioritized molecular classification?

Blood ◽

10.1182/blood-2006-06-001149 ◽

2006 ◽

Vol 109 (2) ◽

pp. 431-448 ◽

Cited By ~ 381

Author(s):

Krzysztof Mrózek ◽

Guido Marcucci ◽

Peter Paschka ◽

Susan P. Whitman ◽

Clara D. Bloomfield

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Tandem Duplication ◽

Gene Mutations ◽

Gene Expression Signature ◽

Genetic Alterations ◽

Expression Signature ◽

Cytogenetically Normal Aml ◽

Acute Myeloid

Abstract Recent molecular analyses of leukemic blasts from pretreatment marrow or blood of patients with acute myeloid leukemia (AML) and a normal karyotype, the largest cytogenetic subset (ie, 40%-49%) of AML, have revealed a striking heterogeneity with regard to the presence of acquired gene mutations and changes in gene expression. Multiple submicroscopic genetic alterations with prognostic significance have been discovered, including internal tandem duplication of the FLT3 gene, mutations in the NPM1 gene, partial tandem duplication of the MLL gene, high expression of the BAALC gene, and mutations in the CEBPA gene. Application of gene-expression profiling has also identified a gene-expression signature that appears to separate cytogenetically normal AML patients into prognostic subgroups, although gene-expression signature-based classifiers predicting outcome for individual patients with greater accuracy are needed. These and similar future findings are likely to have a major impact on the clinical management of cytogenetically normal AML not only in prognostication but also in selection of appropriate treatment, since many of the identified genetic alterations already constitute or will potentially become targets for specific therapeutic intervention. In this report, we review prognostic genetic findings in karyotypically normal AML and discuss their clinical implications.

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The Prognostic Impact of High MEL1 Gene Expression in Pediatric Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v124.21.1009.1009 ◽

2014 ◽

Vol 124 (21) ◽

pp. 1009-1009

Author(s):

Norio Shiba ◽

Kentaro Ohki ◽

Yusuke Hara ◽

Genki Yamato ◽

Myoung-ja Park ◽

...

Keyword(s):

Gene Expression ◽

Myeloid Leukemia ◽

De Novo ◽

Fusion Gene ◽

Genetic Alterations ◽

High Expression ◽

Prognostic Impact ◽

Intermediate Risk ◽

Pediatric Aml ◽

Acute Myeloid

Abstract Background Acute myeloid leukemia (AML) is a complex disease caused by mutations, epigenetic modifications, and deregulated expression of genes, leading to increased proliferation and decreased differentiation of hematopoietic progenitor cells. Although, many prognosis-associated gene alterations have been identified in adult AML, genetic alterations responsible for an adverse outcome in most patients with pediatric AML have remained obscure.In our previous study, we have identified NUP98-NSD1 fusion gene in 6 of 124 pediatric AML patients. As a result of gene expression profile using microarray, all these 6 patients have showed high expression of HOXA9, HOXA10, HOXB3, HOXB5, HOXB6, and a zinc finger transcription factor gene MDS1-EVI1-like-1 (MEL1), and clustered a distinct poor prognostic subgroup [4-year-overall survival (OS); 33%]. Furthermore, this subgroup has also formed the bigger poor prognostic subgroup involving the 18 patients without NUP98-NSD1 fusion gene. We defined this subgroup as NUP98-NSD1 signature consisting of 24 of 124 patients (19%), 4-year-OS; 37.5%. MEL1 gene expression represented the specific characteristics of this subgroup.To verify the significance of MEL1 gene expression and the relationship with other poor prognostic markers such as FLT3-ITD, MLL-PTD, and NPM1, we investigated MEL1 expression by real-time PCR in 369 pediatric AML cases other than acute promyelocytic leukemia (APL) and Down syndrome-associated AML, because these subtypes formed genetically different unique entities and treated by other protocols. Interestingly, MEL1 is highly homologous to MDS1/EVI1 gene, which is an alternatively spliced transcript of the EVI1 genes. As EVI1 high expression has been reported as a poor prognostic marker in pediatric AML patients, especially in patients with MLL rearrangement, we also measured and examined the EVI1 gene expression. Methods Between 2006 and 2010, 485 de novo pediatric AML patients participated in the Japanese AML-05 study conducted by the Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG). Among them, 369 samples were available in this study. Quantitative RT-PCR analysis was performed in these patients using the 7900HT Fast Real Time PCR System with TaqMan Gene Expression Master Mix and TaqMan Gene Expression Assay. In addition to EVI1 and MEL1, ABL1 was also evaluated as a control gene. We investigated the correlations between these gene expressions and other genetic alterations, and clarified the prognostic impact of MEL1 gene. Results A total of 84 of 369 patients (22.8%) showed high expression of MEL1 gene. The number of patients with MEL1 high expressions were gradually enriched in order of the intermediate risk (IR; 34 of 142 patients, or 23.9%), high risk (HR; 21 of 48 patients, or 43.8%), and non-complete remission (non-CR; 20 of 39 patients, or 51.3%), but were almost all absent in patients with a low risk (LR) cytogenetic profile (4 of 120 patients, or 3.3%) consisting of t(8;21) and inv(16). The absolute values of MEL1 gene expression have also gradually increased in order of LR < IR < HR < non-CR. The overall survival among patients with MEL1 high expressions was significantly lower than that among patients without such gene aberrant expression (50% vs. 82%, P<0.001). Remarkably, MEL1 gene expression is extremely useful to stratify the AML patients with FLT3-ITD (4-year OS; high 30% vs. low 75%, P<0.001) and normal karyotype (4-year OS; high 48% vs. low 84%, P<0.001), whom we could not exactly stratify into the appropriate risk so far. On the other hand, a total of 58 of 369 patients (15.7%) have showed high expression of EVI1 gene. The patients with high expression of EVI1 gene have been mainly found in the IR group, especially in patients with MLL rearrangement. Furthermore, MEL1 high group and EVI1high group have the tendency of mutual exclusive in this study. Conclusions MEL1 high expression was highly recurrent in de novo pediatric AML patients with high/intermediate-risk cytogenetic profiles and was independently associated with a poor outcome. Combined with MEL1expression and genetic alterations enable to clarify the genetic background of pediatric AML profiles. The data in this study showed a way in which integrated mutational profiling of a clinical trial cohort can advance our understanding of the biologic characteristics of AML, improve current prognostic models, and inform prospective therapeutic decisions. Disclosures No relevant conflicts of interest to declare.

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Genetic Alterations and Their Clinical Implications in Older Patients with Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v126.23.4956.4956 ◽

2015 ◽

Vol 126 (23) ◽

pp. 4956-4956

Author(s):

Cheng-Hong Tsai ◽

Hsin-An Hou ◽

Wen-Chien Chou ◽

Chien-Chin Lin ◽

Chien-Yuan Chen ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Older Patients ◽

Myeloid Leukemia ◽

Gene Mutations ◽

The Elderly ◽

Genetic Alterations ◽

Patient Specific ◽

Intensive Chemotherapy ◽

P53 Mutations ◽

Acute Myeloid

Abstract Introduction Risk-stratification of patients with acute myeloid leukemia (AML) can not only improve treatment response, but also reduce side effects of the treatment, especially in the elderly. A number of patient-specific and leukemia-associated factors are related to the poor outcome in older patients with AML. However, comprehensive studies regarding the impact of genetic alterations in this group of patients are limited. Methods and Materials A total of 500 adult patients with newly diagnosed de novo AML who had enough bone marrow cryopreserved cells for analysis at the National Taiwan University Hospital were enrolled consecutively. We compared the clinico-biological features, cytogenetics and molecular gene mutations between patients aged 60 years or older (n=185) and those younger (<60 years, n=315). Result Among older patients, those received standard intensive chemotherapy had a longer overall survival (OS) than those treated with palliative care. Compared with younger patients, the elderly had a higher incidence of poor-risk cytogenetic changes, but a lower frequency of favorable-risk cytogenetics. The median number of molecular gene mutations at diagnosis was higher in the elderly than the younger. Older patients had significantly higher incidences of PTPN11, NPM1, RUNX1, ASXL1, TET2, DNMT3A, and P53 mutations but a lower frequency of WT1 mutations. In multivariate analysis for OS among the elderly who received standard intensive chemotherapy, high WBC >50,000/μL at diagnosis, RUNX1 mutations, DNMT3A mutations, and P53 mutations were independent worse prognostic factors, while the presence of NPM1 mutations in the abcence of FLT3/ITD mutations was an independent good prognostic factor. The frequency of acquiring one or more adverse genetic alterations was much higher in older patients than younger ones. Further, the pattern of gene mutations could divide older patients with intermediate cytogenetics into three groups with significantly different complete remission rates, OS, and disease-free survival. Conclusion Older AML patients frequently harbored high-risk cytogenetics and gene mutations, and had poorer prognosis. Integration of cytogenetics and molecular alterations could risk-stratify older patients into groups with significant different outcomes. For those patients with poor prognosis under current chemotherapy, novel therapies, such as demethylating agents or other targeted therapies may be indicated. Disclosures Tang: Novartis: Consultancy, Honoraria.

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Acute Myeloid Leukemia With Biallelic CEBPA Gene Mutations and Normal Karyotype Represents a Distinct Genetic Entity Associated With a Favorable Clinical Outcome

Journal of Clinical Oncology ◽

10.1200/jco.2008.21.6010 ◽

2010 ◽

Vol 28 (4) ◽

pp. 570-577 ◽

Cited By ~ 180

Author(s):

Annika Dufour ◽

Friederike Schneider ◽

Klaus H. Metzeler ◽

Eva Hoster ◽

Stephanie Schneider ◽

...

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Clinical Outcome ◽

Myeloid Leukemia ◽

Expression Profiles ◽

Gene Mutations ◽

Gene Expression Profiles ◽

Similar Frequency ◽

Favorable Clinical Outcome ◽

Acute Myeloid

Purpose CEBPA mutations are found as either biallelic (biCEBPA) or monoallelic (moCEBPA). We set out to explore whether the kind of CEBPA mutation is of prognostic relevance in cytogenetically normal (CN) acute myeloid leukemia (AML). Patients and Methods Four hundred sixty-seven homogeneously treated patients with CN-AML were subdivided into moCEBPA, biCEBPA, and wild-type (wt) CEBPA patients. The subgroups were analyzed for clinical parameters and for additional mutations in the NPM1, FLT3, and MLL genes. Furthermore, we obtained gene expression profiles using oligonucleotide microarrays. Results Only patients with biCEBPA had an improved median overall survival when compared with patients with wtCEBPA (not reached v 20.4 months, respectively; P = .018), whereas patients with moCEBPA (20.9 months) and wtCEBPA had a similar outcome (P = .506). Multivariable analysis confirmed biCEBPA, but not moCEBPA, mutations as an independent favorable prognostic factor. Interestingly, biCEBPA mutations, compared with wtCEBPA, were never associated with mutated NPM1 (0% v 43%, respectively; P < .001) and rarely associated with FLT3 internal tandem duplication (ITD; 5% v 23%, respectively; P = .059), whereas patients with moCEBPA had a similar frequency of mutated NPM1 and a significantly higher association with FLT3-ITD compared with patients with wtCEBPA (44% v 23%, respectively; P = .037). Furthermore, patients with biCEBPA showed a homogeneous gene expression profile that was characterized by downregulation of HOX genes, whereas patients with moCEBPA showed greater heterogeneity in their gene expression profiles. Conclusion Biallelic disruption of the N and C terminus of CEBPA is required for the favorable clinical outcome of CEBPA-mutated patients and represents a distinct molecular subtype of CN-AML with a different frequency of associated gene mutations. These findings are of great significance for risk-adapted therapeutic strategies in AML.

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NADH Dehydrogenase Subunit 4 (ND4) Mutations in Pediatric Acute Myeloid Leukemia

Blood ◽

10.1182/blood.v120.21.1380.1380 ◽

2012 ◽

Vol 120 (21) ◽

pp. 1380-1380

Author(s):

Michael A Morgan ◽

Birgit Markus ◽

Malou Hermkens ◽

Frederik Damm ◽

Katarina Reinhardt ◽

...

Keyword(s):

Gene Expression ◽

Acute Myeloid Leukemia ◽

Complete Remission ◽

Myeloid Leukemia ◽

Nadh Dehydrogenase ◽

Survival Advantage ◽

Nadh Dehydrogenase Subunit ◽

Pediatric Leukemia ◽

Pediatric Aml ◽

Acute Myeloid

Abstract Abstract 1380 NADH dehydrogenase subunit 4 (ND4) is encoded by mitochondrial DNA and is an integral component of Complex I, one of the core enzymatic complexes critical for mitochondrial oxidative phosphorylation and regulation of the balance between NADH and NAD+. ND4 mutations have recently been described in adult acute myeloid leukemia (AML). In the current study, we investigated the frequency and prognostic impact of ND4 mutations in 289 pediatric leukemia patients (<= 18 years). Total cellular DNA was isolated from bone marrow or peripheral blood samples at diagnosis (n=289) and at complete remission (n=6) for children treated uniformly within multicenter treatment trials AML-Berlin-Frankfurt-Münster (BFM, n=180) and Dutch Childhood Oncology Group (DCOG, n=109). ND4 mutations were detected by direct sequencing in 13 of 289 (4.5 %) pediatric AML patients. Mutations occurred throughout the ND4 sequence, and included missense mutations (n=10), deletions (n=2) and a nonsense mutation. The most commonly detected mutations were S86N (n=2), delA 11,032–11,038 (n=2), and F50L (n=2). All other mutations were detected in single cases. Four (30.8 %) ND4 mutations were heteroplasmic (i.e. both wild-type and mutated ND4 were detected) and 9 (69.2 %) were homoplasmic (i.e. only mutated ND4 was detected), which is similar to the distribution we previously observed for adult AML patients (37.9% and 62.1%, respectively). Of the 4 heteroplasmic mutations detected in the pediatric AML cohort, 3 are predicted to result in a truncated ND4 protein. The remaining heteroplasmic mutation, which results in an L72P substitution, is predicted to be damaging (PolyPhen2 score = 0.999). Thus all 4 heteroplasmic mutations are expected to interfere with ND4 protein function. In contrast, 3 of the 9 (33.3 %) homoplasmic mutations are within transmembrane regions and only 1 (11.1 %) is predicted to be damaging (S459Y, PolyPhen2 score = 0.906). The 11 predicted transmembrane domains (TMD) of ND4 may be important for mitochondrial proton transport. However, like in adult AML, the presence of ND4 mutations affecting or not affecting a TMD had no impact on pediatric AML patient outcome. Non-tumoral DNA available through samples collected in routine follow-up examinations during complete remission allowed determination of mutation origin (e.g. somatic or germ-line) in 6 cases. Interestingly, the homoplasmic substitutions resulting in F50L, S86N and A131T were each defined to be germline mutations in both adult and pediatric AML samples. The heteroplasmic one base-pair deletion in a stretch of seven adenine residues (11,032–11,038) detected in two pediatric leukemia samples was determined to be somatic in the one case for whom a sample obtained during complete remission was available for analyses. Patient characteristics including age, FAB-subtype, WBC count, cytogenetic subgroup or presence of FLT3-ITD were similar regardless of ND4 mutation status. In accordance with our earlier observations in adult AML, comparison of ND4mutated with ND4wildtype patients demonstrated no significant difference on overall survival (OS, P=.67). In the adult study, a survival advantage was observed for patients with somatic heteroplasmic ND4 mutations. No survival advantage was observed for children with heteroplasmic ND4 mutations, possibly due to limited numbers of ND4mutated patients treated in the BFM and DCOG study groups. Gene expression profiles (GEP) for ND4mutated (n=11) and ND4wild-type (n=188) pediatric AML patients revealed no significant differences. However, 8 probe sets were found to be differentially regulated when GEP for heteroplasmic ND4mutated (n=4) and ND4wildtype (n=187) were compared. Two of these probe sets annotated the SETDB2 (CLLD8, KMT1F) gene, which encodes a histone H3 methyltransferase. Quantitative RT-PCR validated the lower SETDB2 expression as a characteristic of ND4mutated cases (P=.02). SETDB2 contributes to several important cellular functions, including heterochromatin formation, chromatin condensation and transcriptional repression. In summary, ND4 mutations were not predictive for outcome in pediatric AML, but were significantly associated with decreased SETDB2 expression, providing a link between mitochondrial gene mutation and epigenetic control of gene expression. Disclosures: No relevant conflicts of interest to declare.

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