Prognostic Significance of 11q23/MLL Fusion Partners in Children with Acute Myeloid Leukemia (AML) - Results from the Children's Oncology Group (COG) Trial AAML0531

Abstract Background: Rearrangement of chromosome 11q23 at KMT2A (MLL+) occurs in ~20% of childhood acute myeloid leukemia (AML) cases and is the most common recurrent cytogenetic abnormality in childhood AML. More than 80 fusion partners of MLL have been characterized and the prognostic impact varies by partner and additional cytogenetic aberrations (ACAs). We previously reported superior event-free-survival (EFS), overall survival (OS), relapse risk (RR) and disease free survival (DFS) for patients with MLL+ on AAML0531 treated with gemtuzumab ozogamicin (GO). The impact of fusion partners has not been described for this trial cohort. Objective: To determine the impact of 11q23/MLL+ fusion partners on outcomes for children with AML who were treated uniformly on AAML0531. Methods: AAML0531 (2006 - 2010) was a randomized phase 3 trial of GO with conventional chemotherapy for children, adolescents, and young adults, ages 0 to 29 years, with de novo AML. The trial enrolled 1022 eligible patients without Down syndrome, and cytogenetic data was available for 988 patients. Of those, 215 (21.8%) were classified as 11q23/MLL+ after central cytogenetic review. The majority of patients with 11q23/MLL+ AML (n=200, 93%) were classified as intermediate risk (IR) and a minority (n=15, 7%) were classified as high risk (HR) based upon high FLT3 internal tandem duplication allelic ratio (FLT3-ITD-AR), monosomy 5/5q deletion, monosomy 7, or >15% blasts by morphology following Induction (Ind) I. HSCT was performed for 30 patients (14%). We defined 11q23/MLL+ subgroups for partners identified in ≥5 cases. Partners in <5 cases were grouped as "other"; unidentified fusions were classified as "unknown". Outcomes of minimal residual disease (MRD) at end of Ind I and complete remission (CR) at end of Ind II, 5-yr EFS and OS from study entry, and 5-yr RR from end of Ind II for patients in CR were compared across subgroups. Univariable and multivariable analyses were performed. Results: The median age for the 11q23/MLL+ cohort was 2.5 years and the distribution was equally male and female. The majority of cases (n=175, 81%) were classified into 8 specific partner subgroups, and the remaining cases were classified as other (n=30, 14%) or unknown (n=10, 5%). The most common translocation was t(9;11)(p22;q23) (n= 82, 38%). Central nervous system involvement was rare (<10% overall and in every subgroup). While extramedullary chloromas were rare (7% overall), chloromas were reported in 83% (n=5) of t(10;11)(p11.2;q23), 40% (n=16) of t(10;11)(p12;q23), and 27% (n=4) of t(6;11)(q27;q23). ACAs were observed in 86 of 211 cases (41%) that underwent central review. ACAs were numerical in 54 cases (26%), most commonly trisomy 8 (n=30, 14%) and structural + numerical in 32 cases (15%), most commonly involving chromosome 1 (n=11, 34%). Molecular findings for 3 studied genes were rare: High FLT3-ITD-AR n=4; NPM1 n=1; CEBPA n=0. Clinical outcomes varied significantly by fusion partner and poorer OS was primarily due to relapse (Table 1). CR rate was 86% overall and did not vary by subgroups. MRD was detected in 21% overall and was most common in t(1;11)(q21;q23) and t(6;11)(q27;q23). Complex karyotype (≥3 abnormalities) was seen in 52 cases (25%) and predicted inferior outcome compared to <3 abnormalities (5-yr EFS 29% vs. 41%, p=0.02; 5-yr OS 44% vs. 63%, p=0.001, respectively). Chromosome 1 abnormalities were associated with very poor outcomes, 5-yr EFS 19% and 5-yr OS 29%. The most unfavorable partners for EFS were t(6;11)(q27;q23), t(10;11)(p11.2;q23), t(10;11)(p12;q23), and t(11;19)(q23;p13.3)(Figure 1). In multivariable comparison to patients with t(9;11)(p22;q23), the former 3 groups maintained inferior EFS (HR 2.51, p=0.006; HR 3.10, p<0.001; HR 2.15, p=0.002, respectively) and OS (HR 2.56, p=0.017; HR 4.8, p=0.006; HR 2.14, p=0.016, respectively). Conclusions: Fusion partners critically impact the prognosis of 11q23/MLL+ AML. In this large, uniformly treated cohort, t(6;11)(q27;q23), t(10;11)(p11.2;q23) and t(10;11)(p12;q23) were independently associated with inferior EFS and OS. Children with these unfavorable partners are at high risk for relapse and allogeneic HSCT should be considered in first CR. Complex karyotype, chromosome 1 aberrations, and extramedullary chloromas were additional adverse prognostic factors. Work is ongoing to confirm these results in the subsequent COG trial, AAML1031. Disclosures No relevant conflicts of interest to declare.

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Quantification of VEGF Isoforms and VEGFR Transcripts by qRT-PCR and Their Significance in Acute Myeloid Leukemia

The International Journal of Biological Markers ◽

10.1177/172460080902400104 ◽

2009 ◽

Vol 24 (1) ◽

pp. 22-31 ◽

Cited By ~ 10

Author(s):

Samia Mourah ◽

Raphaël Porcher ◽

Géraldine Lescaille ◽

Philippe Rousselot ◽

Marie-Pierre Podgorniak ◽

...

Keyword(s):

Overall Survival ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Univariate Analysis ◽

Prognostic Impact ◽

Mrna Levels ◽

Event Free Survival ◽

Free Survival ◽

The Impact ◽

Acute Myeloid

Vascular endothelial growth factor (VEGF) and its receptors are known to play an important role in normal and pathological hematopoiesis but the prognostic impact of VEGF isoform transcripts in acute myeloid leukemia (AML) has not been addressed. We conducted a single-institution prospective study to analyze the impact of these angiogenic factors and the expression of their receptors on the survival of adult patients newly diagnosed with AML. We investigated the levels of VEGF transcript isoforms VEGF121, -145, -165, -189 and -206 and their receptors, VEGFR-1 and VEGFR-2, using quantitative reverse transcriptase polymerase chain reaction assays in peripheral blood mononuclear cells (PBMCs) of 67 consecutive AML patients at diagnosis. VEGF total protein was measured for comparison with mRNA levels in PBMCs. The VEGF121 splice variant transcript in AML PBMCs was significantly higher than in the normal controls. VEGF transcripts were quantified in all samples while its protein was detected in 42/67 (63%) of AML samples. High levels of VEGF121, VEGF165 transcripts and VEGF protein in AML were significantly related to a worse prognosis when analyzing overall survival (p<0.0001, p=0.019 and p=0.012, respectively) or event-free survival (p<0.0001, p=0.010 and p=0.047) using univariate analysis. In multivariable analysis only VEGF121 expression remained an independent prognostic factor for either event-free survival or overall survival [aHR=8.83 (3.48–22.4), p<0.0001, and aHR=9.52 (3.41–26.6), p<0.0001]. No prognostic value was observed for the other isoforms and the two receptors. Our findings show that the level of VEGF121 mRNA in circulating cells from AML patients is a strong independent prognostic parameter, which could be useful in the management of unselected AML patients.

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Prognostic impact of WT1 mutations in cytogenetically normal acute myeloid leukemia: a study of the German-Austrian AML Study Group

Blood ◽

10.1182/blood-2008-10-183392 ◽

2009 ◽

Vol 113 (19) ◽

pp. 4505-4511 ◽

Cited By ~ 116

Author(s):

Verena Ingeborg Gaidzik ◽

Richard Friedrich Schlenk ◽

Simone Moschny ◽

Annegret Becker ◽

Lars Bullinger ◽

...

Keyword(s):

Overall Survival ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Negative Impact ◽

Serum Lactate Dehydrogenase ◽

Study Group ◽

Prognostic Impact ◽

Relapse Free Survival ◽

Free Survival ◽

Acute Myeloid

AbstractTo evaluate the incidence and clinical impact of WT1 gene mutations in younger adult patients with cytogenetically normal acute myeloid leukemia (CN-AML), sequencing of the complete coding region was performed in diagnostic samples from 617 patients who were treated on 3 German-Austrian AML Study Group protocols. WT1 mutations were identified in 78 (12.6%) of the 617 patients; mutations clustered in exon 7 (54 of 78) and exon 9 (13 of 78), but also occurred in exons 1, 2, 3, and 8. WT1 mutations were significantly associated with younger age, higher serum lactate dehydrogenase levels, higher blood blast counts, and the additional presence of FLT3-ITD (P < .001) and CEBPA mutations (P = .004). There was no difference in relapse-free survival and overall survival between patients with (WT1mut) or without WT1 mutations. Subset analysis showed that patients with the genotype WT1mut/FLT3-ITDpos had a lower complete remission rate (P = .003) and an inferior relapse-free survival (P = .006) and overall survival (P < .001) compared with those with the genotype WT1mut/FLT3-ITDneg. In conclusion, in our large cohort of younger adults with CN-AML, WT1 mutation as a single molecular marker did not impact on outcome. However, our data suggest a negative impact of the genotype WT1mut/FLT3-ITDpos.

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Expression of CD25 on Acute Myeloid Leukemia (AML) Blasts Is An Independent Risk Factor Associated with Refractory Disease, Which May Be Overcome by Stem Cell Transplantation (SCT),

Blood ◽

10.1182/blood.v118.21.3560.3560 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3560-3560

Author(s):

Jan Cerny ◽

Lesley Woods ◽

Hongbo Yu ◽

Muthalagu Ramanathan ◽

Glen D Raffel ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Multivariate Analysis ◽

Stem Cell ◽

High Risk ◽

Stem Cell Transplantation ◽

Cell Transplantation ◽

Myeloid Leukemia ◽

Prognostic Impact ◽

Cd25 Expression ◽

Acute Myeloid

Abstract Abstract 3560 Introduction: Acute myeloid leukemia (AML) originates from rare leukemia stem cells (LSCs). LSCs are chemotherapy resistant and responsible for disease recurrence. AML containing a high percentage of LSCs displays aggressive biology in animal models. Using humanized mice Saito et al (Sci Transl Med 2010; 2: 1–11) have recently shown that xenografted CD25+ LSCs initiate AML and are chemotherapy resistant. Confirmation with clinical data from human AML is needed. Methods: In order to determine the prognostic impact of CD25 expression on AML outcome we have retrospectively investigated CD25 expression in 56 patients (pts) diagnosed and treated for AML at our institution between 02/2008 to 05/2011. 46 pts who had non-APL morphology, were treated with induction chemotherapy and had an adequate specimen for CD25 assessment were included in further analysis. CD25 expression was assessed in each specimen by flow cytometry and immunohistochemistry and correlated with clinical outcome. Patients: Median age was 61 years (22–84), 18 (39%) pts were older than 65; F:M ratio was 19:27, 3 (7%) patients had good risk (core binding factor leukemias), 26 intermediate (diploid karyotype and no good or high risk; 57%) and 17 (37%) high risk cytogenetics (complex, anbormality of 3q26, monosomy 7 and 5). 6 (13%) pts had NPM1mut/FLT3-ITDwt, 6 (13%) pts had NPM1wt/FLT3-ITDmut and 9 (13%) pts had NPM1mut/FLT3-ITDmut. As induction high dose cytarabine/anthracycline based regimen was used in 36 (78%) pts, 7 pts received 7+3 (15%) and 3 (7%) pts received hypomethylating agent. 24 (53%) pts received stem cell transplantation (SCT; 16 [35%] allogeneic and 8 [17%] autologous). The median follow up of the surviving pts was 11.2 months (1.1–38.7). Results: CD25 was detected in 17 pts (37%; 16 at diagnosis and 1 at relapse). Six CD25+ pts experienced relapse (3 pts with 3 or more relapses) heralded by increase in the percentage of CD25+ blasts. 65% of pts with CD25+ AML also had FLT3-ITDmut (p=0,0012). When comparing CD25+ and CD25- pts there was no statistical difference in distribution of the following characteristics: sex, age (65+), cytogenetics risk, presence of NPM1mut, type of induction, SCT. Fifteen (88%) of CD25+ pts experienced relapse compared to 8 (28%) of CD25- pts (p= 0.00007), 8 (47%) CD25+ pts died and 9 (31%) CD25- pts died (p=ns). The median relapse free survival (RFS) of all pts was 10.8 months with the median overall survival (OS) 12.2 months. The estimated 6-month RFS was significantly decreased in CD25+ pts compared to CD25- pts (26% vs 79%, p= 0.0003). This did not translate into a difference in OS between both groups (1-year OS: CD25+ 43% vs CD25- 65%, p=ns). In univariate analysis CD25 positivity was a stronger predictor for relapse (HR 5.28 [2.21–12.62], p=0.0002) than FLT3-ITDmut (HR 4.72 [2.04–10.92]; p= 0.0003). In multivariate analysis CD25 positivity was also a stronger predictor for relapse (HR 6.54 [1.34–9.15], p=0.01) than FLT3-ITDmut (HR 4.72 [2.04–10.92], p= 0.03). Pts undergoing SCT had significantly longer 1-year OS (66%) compared to pts without SCT (21%; p=0.0004). In multivariate analysis SCT was a predictor for improved OS (HR 0.2 [0.07–0.57], p=0.0002). CD25+ pts who received SCT had also significantly longer 1-year OS (63%) compared to CD25+ pts who did not receive SCT (0%; p=0.0098). SCT did not impact RFS in either group. Conclusion: CD25 represents a novel prognostic factor in AML. The increase in CD25+ blasts at relapse is associated with increased relapsed rate and refractory AML supporting the LSCs hypothesis. The detection of CD25 serves not only as a prognostic marker, but may be valuable for minimal residual disease assessment in patients who lack a molecular marker. In our experience treatment inclusive of stem cell transplantation abrogated the negative impact of CD25 expression on OS. Exploration of CD25 as a therapeutic target in AML is warranted. Disclosures: No relevant conflicts of interest to declare.

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TP53 Alterations in Acute Myeloid Leukemia with Complex Karyotype Correlate with Specific Copy Number Alterations, Monosomal Karyotype, and Dismal Outcome,

Blood ◽

10.1182/blood.v118.21.3558.3558 ◽

2011 ◽

Vol 118 (21) ◽

pp. 3558-3558 ◽

Cited By ~ 3

Author(s):

Frank G. Rücker ◽

Richard F. Schlenk ◽

Lars Bullinger ◽

Sabine Kayser ◽

Veronica Teleanu ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Copy Number ◽

Myeloid Leukemia ◽

Multivariable Analysis ◽

Complex Karyotype ◽

Copy Number Alterations ◽

Free Survival ◽

Genomic Complexity ◽

Monosomal Karyotype ◽

Acute Myeloid

Abstract Abstract 3558 Acute myeloid leukemia with complex karyotype (CK-AML, CK+) is defined as ≥3 acquired chromosome abnormalities in the absence of recurrent genetic abnormalities (WHO 2008). CK-AML account for 10–15% of all AML and are characterized by a dismal outcome. To delineate prognostic markers in this unfavorable subgroup, we performed integrative analysis using genomic profiling (array-comparative genomic hybridization [CGH] and/or single-nucleotide polymorphism [SNP] analysis), as well as TP53 mutation screening in 234 CK-AML. TP53 mutations were found in 141/234 (60%) CK-AML comprising 130 missense, 21 insertion/deletion, nine nonsense, and eight splice site mutations; genomic losses of TP53 were identified in 94/234 (40%). Combining these data, TP53 alterations were detected in 70% of patients, and at least 66% of these exhibited biallelic alterations. TP53 alterations (loss and/or mutation in TP53) were characterized by a higher degree of genomic complexity, as measured by total number of copy number alterations per case (mean±SD 14.30±9.41 versus 6.16±5.53, P <.0001), and by the association with specific genomic alterations, that is, monosomy 3 or losses of 3q (-3/3q-) (P=.002), -5/5q- (P<.0001), -7/7q- (P=.001), -16/16q- (P<.0001), -18/18q- (P=.001), and -20/20q- (P=.004); gains of chromosome 1 or 1p (+1/+1p) (P=.001), +11/+11q (P=.0002), +13/+13q (P =.02), and +19/+19p (P =.04); and amplifications in 11q13∼25 [amp(11)(q13∼25)]. The recently described cytogenetic category “monosomal karyotype” (MK), defined as two or more autosomal monosomies or one single autosomal monosomy in the presence of structural abnormalities, for which a prognostic impact could be demonstrated even in CK-AML, was correlated with TP53 alterations (P <.0001). Clinically, TP53altered CK-AML patients were older (median age, 61 versus 54 years, P =.002), had lower bone marrow (BM) blast counts (median 65% versus 78%, P=. 04), and had lower complete remission (CR) rates (28% versus 50%, P =.01). For multivariable analysis, a conditional model was used with an age cut point at 60 years to address the different treatment intensities applied in the different age cohorts. In this model the only significant factors for CR achievement were TP53altered (OR, 0.55; 95%-CI, 0.30 to 1.00; P =.05) and age (OR for a 10 years difference, 0.67; 95%-CI, 0.52 to 0.87; P =.003). TP53 altered predicted for inferior survival; the 3-year estimated survival rates for CK+/TP53altered and CK+/TP53unaltered patients were as follows: event-free survival (EFS), 1% versus 13% (log-rank, P =.0007); relapse-free survival (RFS), 7% versus 30% (P =.01); and overall survival (OS), 3% versus 28% (P <.0001), respectively. Other variables predicting for inferior OS in univariable analyses were age and MK. Among the cohort of CK+/MK+ AML, TP53altered patients had a significantly worse OS (P =.0004). Multivariable analysis (stratified for age at cut point of 60 years) revealed TP53altered (HR, 2.43; 95%-CI, 1.56 to 3.77; P =.0001), logarithm of WBC (HR, 1.62; 95%-CI 1.17 to 2.26; P =.004), and age (HR for 10 years difference, 1.26; 95%-CI, 1.01 to 1.56, P =.04), but not MK as significant variables for OS. In addition, explorative subset analysis suggested that allogeneic hematopoietic stem-cell transplantation in first CR which was performed in 30 CK-AML did not impact outcome in TP53altered CK-AML. In summary, TP53 is the most frequently known altered gene in CK-AML. TP53 alterations are associated with older age, genomic complexity, specific DNA copy number alterations, MK, and dismal outcome. In multivariable analysis, TP53 alteration is the most important prognostic factor in CK-AML, outweighing all other variables, including the MK category. TP53 mutational status should be assessed in clinical trials investigating novel agents in order to identify compounds that may be effective in this subset of patients. Disclosures: No relevant conflicts of interest to declare.

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Augmented Reduced-Intensity Regimen Does Not Improve Postallogeneic Transplant Outcomes in Acute Myeloid Leukemia

Journal of Clinical Oncology ◽

10.1200/jco.20.02308 ◽

2020 ◽

pp. JCO.20.02308

Author(s):

Charles Craddock ◽

Aimee Jackson ◽

Justin Loke ◽

Shamyla Siddique ◽

Andrea Hodgkinson ◽

...

Keyword(s):

Overall Survival ◽

Acute Myeloid Leukemia ◽

T Cell ◽

High Risk ◽

Myeloid Leukemia ◽

Conditioning Regimen ◽

Hazard Ratio ◽

Prognostic Impact ◽

Reduced Intensity ◽

Acute Myeloid

PURPOSE Reduced-intensity conditioning (RIC) regimens have extended the curative potential of allogeneic stem-cell transplantation to older adults with high-risk acute myeloid leukemia (AML) and myelodysplasia (MDS) but are associated with a high risk of disease relapse. Strategies to reduce recurrence are urgently required. Registry data have demonstrated improved outcomes using a sequential transplant regimen, fludarabine/amsacrine/cytarabine-busulphan (FLAMSA-Bu), but the impact of this intensified conditioning regimen has not been studied in randomized trials. PATIENTS AND METHODS Two hundred forty-four patients (median age, 59 years) with high-risk AML (n = 164) or MDS (n = 80) were randomly assigned 1:1 to a fludarabine-based RIC regimen or FLAMSA-Bu. Pretransplant measurable residual disease (MRD) was monitored by flow cytometry (MFC-MRD) and correlated with outcome. RESULTS There was no difference in 2-year overall survival (hazard ratio 1.05 [85% CI, 0.80 to 1.38] P = .81) or cumulative incidence of relapse (CIR) (hazard ratio 0.94 [95%CI, 0.60 to 1.46] P = .81) between the control and FLAMSA-Bu arms. Detectable pretransplant MFC-MRD was associated with an increased CIR (2-year CIR 41.0% v 20.0%, P = .01) in the overall trial cohort with a comparable prognostic impact when measured by an unsupervised analysis approach. There was no evidence of interaction between MRD status and conditioning regimen intensity for relapse or survival. Acquisition of full donor T-cell chimerism at 3 months abrogated the adverse impact of pretransplant MRD on CIR and overall survival. CONCLUSION The intensified RIC conditioning regimen, FLAMSA-Bu, did not improve outcomes in adults transplanted for high-risk AML or MDS regardless of pretransplant MRD status. Our data instead support the exploration of interventions with the ability to accelerate acquisition of full donor T-cell chimerism as a tractable strategy to improve outcomes in patients allografted for AML.

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ABCB1 Expression in Acute Myeloid Leukemia (AML): A Possible Predictive Value for Treatment Resistance?

Blood ◽

10.1182/blood.v124.21.3618.3618 ◽

2014 ◽

Vol 124 (21) ◽

pp. 3618-3618

Author(s):

Stephany Corrêa ◽

Eliana Abdelhay ◽

Peter Paschka ◽

Verena I. Gaidzik ◽

Rocio Hassan ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Induction Therapy ◽

Myeloid Leukemia ◽

Induction Treatment ◽

Mrna Levels ◽

Complex Karyotype ◽

Hematopoietic Stem ◽

Expression Levels ◽

The Impact ◽

Acute Myeloid

Abstract Introduction: Over the last years, there has been a tremendous increase in understanding acute myeloid leukemia (AML) biology and a great effort has been taken in order to improve AML chemotherapy strategies. However, the growing knowledge of leukemia associated molecular mechanisms just started to translate into improved outcome. With regard to conventional chemotherapy multidrug resistance (MDR) is a persisting problem and the impact of ABCB1 (MDR1) expression is still controversially discussed. Methods: In this study we evaluated the ABCB1 expression using qRT-PCR and gene expression profiling (Affymetrix U133plus2.0 arrays) in 250 diagnostic AML samples derived from patients enrolled on a prospective treatment trial of the German-Austrian AML Study Group (AMLSG 07-04 trial; NCT00151242), in which patients were treated with an intensive anthracycline/cytarabine-based induction therapy. Findings were also evaluated in 154 TCGA AML cases receiving a 7+3 induction treatment (data available at http://cancergenome.nih.gov/) and put into perspective with previous reports. Furthermore, we investigated ABCB1 expression associated gene signatures and examined epigenetic regulation mechanisms by COBRA and methyl-CpG immunoprecipitation sequencing (MCIp-seq) in selected cases. Results: Our global analysis showed that patients who obtained a complete response (CR) following double induction therapy had lower ABCB1 mRNA levels compared to patients with refractory disease (RD) (p=0.07). Regarding cytogenetic AML subtypes, ABCB1 mRNA levels varied among the different cytogenetic groups with the complex karyotype group showing the highest ABCB1 and the inv(16) group the lowest ABCB1 expression levels. A comparison of CR versus RD cases within the cytogenetically determined prognostic groups showed that in the intermediate [CN-AML, t(11q23), and other intermediate risk cytogenetic aberrations (othersinter)] and poor risk groups (complex karyotype and othershigh), RD patients presented with significantly higher ABCB1 mRNA levels (p=0.02). Similarly, patients with favorable risk cytogenetics [t(8;21) and inv(16)], who achieved a CR, presented with lower ABCB1 levels compared to the ones, who were refractory. Patients with the lowest ABCB1 expression quartile (ABCB1low) showed significantly longer event-free survival (EFS) times than patients in the highest quartile cohort (ABCB1high) (median EFS 322 vs 105 days; p=0.02), while no differences were observed with regard to overall survival. In accordance, there was a significant enrichment of RD cases in the ABCB1high patient group (p=0.03). Next, in order to better understand the regulation of ABCB1 in AML, we specifically evaluated the DNA methylation level of a previously identified GC box important for ABCB1 expression regulation in CML and we performed global analyses of the entire ABCB1 5' region. While both analyses did not reveal significant differences, further investigation of an ABCB1 associated gene pattern showed a correlation with CD34 and KIT expression (p<0.001). This suggests that like in CML, ABCB1 might be regulated by WNT, and in line, normal CD34+ hematopoietic stem cells also showed high ABCB1 expression levels. Conclusions: In summary, our data provide further evidence for a potential impact of ABCB1 deregulation on the response to AML chemotherapy, especially in more stem cell like leukemia cohorts as well as cytogenetically high risk AML. While we are currently further investigating the involvement of the Wnt/β-catenin pathway in the regulation of ABCB1 transcription in AML, further integration of molecular findings are warranted to better decipher the underlying drug resistance mechanisms. Ultimately, these analyses will improve patient management by adding valuable predictive biomarkers. Disclosures No relevant conflicts of interest to declare.

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Clonal Involvement of the CD34+CD33− Progenitor Population by Leukemic Cells Harboring FLT3/ITD Correlates with High Risk of Relapse in Pediatric Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v106.11.227.227 ◽

2005 ◽

Vol 106 (11) ◽

pp. 227-227

Author(s):

Jessica A. Wright ◽

Todd A. Alonzo ◽

Robert B. Gerbing ◽

William G. Woods ◽

Beverly J. Lange ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

High Risk ◽

Clinical Outcome ◽

Myeloid Leukemia ◽

Poor Clinical Outcome ◽

Free Survival ◽

Allelic Ratio ◽

Risk Of Relapse ◽

Acute Myeloid

Abstract Internal tandem duplication of the FLT3 gene (FLT3/ITD) has been associated with high risk of relapse in acute myeloid leukemia (AML) yet nearly 25–30% of the patients with FLT3/ITD have long-term disease free survival with conventional chemotherapy. We hypothesized that FLT3/ITD AML patients with poor clinical outcome may have disease that involves less mature hematopoietic precursors than patients with favorable outcome. To test this hypothesis, we isolated less mature, CD34+CD33− and more mature, CD34+CD33+ precursor cells from 24 pediatric AML patients enrolled on Children’s Cancer Group clinical trials CCG-2891 and 2961 previously identified as having a FLT3/ITD. Granulocyte/monocyte colonies (CFU-GM) were grown in methylcellulose, harvested, and analyzed for the presence of FLT3/ITD after 14 days of growth. Twenty patients yielded sufficient cells and growth of CFU-GM colonies for analysis. FLT3/ITD was detected in CFU-GM colonies derived from CD34+CD33+ cells in all patient samples (median 80% of colonies tested per patient, range 6–100%). In contrast, FLT3/ITD was detected in CFU-GM colonies derived from CD34+/CD33− cells in only 11 of the 20 patient samples (median 46% of colonies tested per patient, range 6–100%). Of the 9 patient samples without FLT3/ITD involvement of CD34+CD33− colonies, 8 achieved a CR, 6 of whom are long-term survivors, and one patient died of non-leukemic causes. In contrast, of the 11 patients with CD34+CD33− cell involvement, 9 either failed to achieve CR or relapsed after achieving CR, and 2 died of non-leukemic causes. Actuarial progression-free survival at 4 years from diagnosis for the patients with and without FLT3/ITD in the CD34+CD33− population was 0% vs. 68% respectively (p=0.017). As allelic ratio of the FLT3/ITD has been used to define high-risk patients within the FLT3/ITD cohort, we determined the FLT3/ITD allelic ratio in our study population and correlated it with the presence of FLT3/ITD in the CD34+CD33− population. Ten of the 11 (91%) of the patient samples with FLT3/ITD involvement of the progenitor cells had high allelic ratio compared to 5 of 9 (56%) of the patients without early cell involvement. Together these data suggest that clonal dominance of FLT3/ITD containing leukemia cells at the CD34+CD33− stage of hematopoietic development is correlated with a high risk of relapse. Further studies are required to determine whether clonal dominance at this hematopoietic stage is a variable that, independent of high allelic ratio, accounts for the poor clinical outcome seen in a subset of FLT3/ITD positive AML patients.

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The Amount of Mitochondrial Apoptosis Exerts Prognostic Impact on Normal Karyotype Acute Myeloid Leukemia.

Blood ◽

10.1182/blood.v112.11.1481.1481 ◽

2008 ◽

Vol 112 (11) ◽

pp. 1481-1481

Author(s):

Giovanni Del Poeta ◽

Maria Ilaria Del Principe ◽

Francesco Buccisano ◽

Luca Maurillo ◽

Benedetta Neri ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Disease Free Survival ◽

Normal Karyotype ◽

Mitochondrial Proteins ◽

Prognostic Impact ◽

Mitochondrial Apoptosis ◽

P Glycoprotein ◽

The Impact ◽

Acute Myeloid

Abstract The unbalance between anti-apoptotic (bcl-2) and pro-apoptotic mitochondrial proteins (bax) represents a critical mechanism explaining the high rate of resistance and treatment failure in acute myeloid leukemia (AML) (Del Poeta, 2003). Moreover, the availability of novel and effective pro-apoptotic compounds such as bortezomib (Attar, 2008) and gemtuzumab (Del Poeta, 2008) moved us to widely investigate the impact of mitochondrial proteins such as bcl-2, bax and 7A6 on AML prognosis. 7A6 antigen has been found to be exposed on the mitochondrial membrane during the early stages of apoptosis and is recognized by monoclonal antibody APO2.7. For this purpose, a large series of 420 non M3 AML patients (pts), median age 63 years, treated with intensive chemotherapy regimens, were tested. The aims of our research were: to correlate bax/bcl-2 and APO2.7/bcl-2 ratios, as measures of mitochondrial apoptosis, with other well-known prognostic factors such as age, cytogenetics, FLT3-ITD, P-glycoprotein; to evaluate whether mitochondrial apoptosis was able to dissect normal karyotype AML with regard to prognosis, and finally to confirm that mitochondrial apoptosis is an independent prognostic factor. Bcl-2, bax and 7A6 proteins were assessed by multicolor flow cytometry and bax/bcl-2 or APO2.7/bcl-2 ratios were obtained by dividing mean fluorescence intensity (MFI) of bax/MFI bcl-2 or MFI of APO2.7/MFI bcl-2. The thresholds of positivity were set at the median values >0.35 and >0.60, respectively. Fifty-nine percent of pts were bax/bcl-2 positive and 50% were APO2.7/bcl-2 positive. There were strict correlations between higher bax/bcl-2 or higher APO2.7/bcl-2 and FAB M2 or M4/M5 AML subgroups (p<0.0001). Bax/bcl-2>0.35 or APO2.7/bcl-2>0.60 and CD34 negativity (p<0.0001) or normal karyotype (p<0.0001 and p=0.003) were closely associated. On the other hand, no significant relationships were found between bax/bcl-2 or APO2.7/bcl-2 and age, white blood cell count, P-glycoprotein or FLT3-ITD. A higher complete remission (CR) rate was found in pts either with higher bax/bcl-2 or higher APO2.7/bcl-2 (68% vs 32% and 60% vs 40%, p<0.0001). Moreover, a shorter time to relapse was observed in pts with bax/bcl-2 <0.35 (3.3 months vs 6 months, p=0.011). Overall survival (OS) and disease-free survival (DFS) were longer in pts with higher bax/bcl-2 (18% vs 0% at 3.5 years, p<0.0001 and 19 vs 0% at 2.7 years, p=0.00007) or higher APO2.7/bcl-2 (14% vs 2% at 4 years, p<0.0001 and 8% vs 0% at 4 years, p=0.02). Furthermore, in order to demonstrate the independent prognostic impact of the mitochondrial proteins, we investigated bax/bcl-2 and APO2.7/bcl-2 within the normal karyotype subgroup (243 pts). As a matter of fact, within this subset, higher bax/bcl-2 or higher APO2.7/bcl-2 were associated with higher CR rate (76% vs 24% and 64% vs 36%, p<0.0001) and longer OS (16% vs 0% at 3.5 years, p=0.00001 and 14% vs 4 at 4 years, p=0.002). The independent prognostic value of bax/bcl-2 and APO2.7/bcl-2 was confirmed in multivariate analysis with regard to CR (p=0.00007 and p=0.0005) and OS (p=0.0009 and p=0.03). Therefore, the significant and independent prognostic role of mitochondrial apoptosis implies that therapeutic strategies for improving outcome in AML should be focused on apoptosis-inducing compounds combined with conventional chemotherapy.

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Prognostic Value of Monosomal Karyotype in Patients with Primary Acute Myeloid Leukemia On Behalf of Spanish CETLAM Group.

Blood ◽

10.1182/blood.v114.22.1003.1003 ◽

2009 ◽

Vol 114 (22) ◽

pp. 1003-1003 ◽

Cited By ~ 3

Author(s):

Isabel Granada ◽

Salut Brunet ◽

Montserrat Hoyos ◽

Dolors Costa ◽

Anna Aventín ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

De Novo ◽

Conflicts Of Interest ◽

Treatment Strategies ◽

Disease Free Survival ◽

Prognostic Impact ◽

Complex Karyotype ◽

Monosomal Karyotype ◽

Acute Myeloid

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.

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Prognostic Implication of Chromosome 17 Abnormalities in the Context of Monosomal Karyotype (MK) in Patients with Acute Myeloid Leukemia (AML) and Complex Cytogenetics

Blood ◽

10.1182/blood.v118.21.1495.1495 ◽

2011 ◽

Vol 118 (21) ◽

pp. 1495-1495

Author(s):

Aziz Nazha ◽

Vijaya R Bhatt ◽

Graciela Nogueras-Gonzalez ◽

Tapan Kadia ◽

Jorge E. Cortes ◽

...

Keyword(s):

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Conflicts Of Interest ◽

Chromosome 17 ◽

Cancer Center ◽

Poor Performance Status ◽

Complex Karyotype ◽

The Impact ◽

Monosomal Karyotype ◽

Acute Myeloid

Abstract Abstract 1495 Background: Monosomal karyotype (MK) is a stronger indicator of dismal clinical outcome than complex karyotype alone among patients with acute myeloid leukemia (AML) (J Clin Oncol 26: 4791–4797). We previously reported that Chromosome 17 abnormalities are associated with worse overall and relapse free survival among patients with AML and complex karyotype (ASH 2009, Borthakur et al #1501). Objectives: To investigate the impact of chromosome 17 abnormalities on the overall survival (OS) and eventfree survival (EFS) in AML patients (pts) with complex cytogenetics after monosomal karyotype is taken into account. Patients and Method: We conducted a review of 1086 pts with newly diagnosed AML treated at MD Anderson Cancer Center between January 1998 and December 2007. Four hundred eighty-three pts had complex cytogenetics defined by the presence ≥ 3 unrelated cytogenetic abnormalities and 37 patients were excluded from the final analysis because of poor performance status (≥ 3 ECOG) at presentation, a population least likely to be offered therapy. Monosomal karyotype (MK+) was defined as presence of at least an autosomal monosomy and a structural chromosomal abnormality or at least two autosomal monosomies. Cox proportional hazards regression was used to model the association between potential prognostic factors and survival (OS and EFS). The Kaplan-Meier product limit method was used to estimate the median time to death or event. Statistical analysis was performed using STATA/SE version 11.2 statistical software (Stata Corp. LP, College Station, TX). Result: Of the 446 pts with complex cytogenetics, 342 (76.7%) pts had MK and 183 (41.0%) pts had chromosome 17 abnormalities (Ch17+). The median age for the entire cohort was 64 years (range: 13–86). One hundred eighty-one (40.6%) pts achieved complete remission (CR/CRp) after induction chemotherapy, 173 (38.8%) pts had resistant disease and 89 (19.9%) had early death. Median OS among pts with MK+ was 4.7 months compared with 8.4 months in MK- patients (Hazard ratio [HR]: 1.37, 95%CI: 1.09–1.72, p=0.006) and was 4.4 months among pts with Ch17+ compared with 6.7 months for Ch17- (HR: 1.28, 95%CI: 1.05–1.55, p=0.014) (Fig.1). Within the group of patients with MK+, additional presence of Ch17 abnormalities was associated with worse OS (HR: 1.23, 95%CI: 1.00, 1.53, p=0.046).On multivariate analysis age, high WBC and MK+ (HR: 1.47, 95%CI: 1.17–1.85, p=0.001) were the variables associated with shorter OS to the exclusion of Ch17+. On the other hand age, higher WBC and Ch17+ (HR: 1.25, 95%CI: 1.04–1.50, p=0.019) were the variables that correlated to shorter EFS to the exclusion of MK+. Conclusion: Among patients with AML and complex cytogenetics, monosomal karyotype is associated with poor outcomes. Additional presence of chromosome 17 abnormalities further worsen outcome in this particularly poor-risk patients with AML. Disclosures: No relevant conflicts of interest to declare.

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