scholarly journals Day 14 Measurable Residual Disease As a Predictor of Post-Induction Response in Patients with Acute Myeloid Leukemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1287-1287
Author(s):  
Reyes María Martín-Rojas ◽  
Jon Badiola ◽  
Pablo Silva De Tena ◽  
Ana Pérez-Corral ◽  
Ignacio Gómez-Centurión ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Bone Marrow Aspiration ◽  
Advisory Committees ◽  
Post Induction ◽  
Measurable Residual Disease ◽  
Acute Myeloid

Abstract INTRODUCTION Several studies have shown that morphological remission at day 14 is a predictor of post-induction response in patients with acute myeloid leukemia (AML) undergoing an intensive treatment. However, the role of measurable residual disease (MRD) by multiparameter flow cytometry (MFC) at day 14 remains unknown. The aim of our study is to explore the role of MRD at day 14 and its association with outcomes of patients with AML undergoing an intensive treatment. METHODS We conducted a retrospective study in adult patients with newly a diagnosed AML in our center between 2007 and 2020. Adult patients who received intensive chemotherapy, excluding those with an acute promyelocytic leukemia, were included. Bone marrow aspiration was performed at day 14 after induction to assess morphological response and MRD by MFC. Early blast clearance (EBC) was defined as <5% of blasts and negative MRD was defined as <0.1% abnormal cells within mononucleated cells by MFC. Day 14 aspiration findings were compared with clinical data. This study was approved by our Institutional Ethics Committee. Data were analyzed using IBM SPSS Statistics version 24. RESULTS A total of 131 patients were analyzed. Median age was 55.6 years (IQR 42.3-64.2). The most frequent AML subtype was AML with myelodysplasia-related changes (34.4%), followed by NPM1-mutated AML (32.1%). The most commonly used induction regimen was "7+3" (96.2%) (Table 1). On day 14 bone marrow aspiration, median cellularity was 0.5/5 (IQR 0.5-1). 107 patients (81.7%) showed a blast reduction >50% compared to diagnosis and 87 patients (66.4%) had less than 5% of blasts. In this latter group, 28.6% of patients had a positive MRD and 71.4% had a negative MRD. NPM1-mutated AML showed the highest EBC rates while AML with myelodysplasia-related changes had the lowest rates (83.3% versus 55.5%; p=0.04). Furthermore, there were statistically significant differences in EBC rates based on the 2017 European Leukemia Net risk stratification, with 80% of EBC in low risk, 66.6% in intermediate risk and 53.4% in high risk AML (p=0.038). No differences were observed in MRD at day 14 based on AML subtypes or risk stratification. We subsequently analyzed the negative (NPV) and positive predictive values (PPV) of day 14 bone marrow aspiration results by morphology and MFC to predict post-induction results. As a predictor of post-induction CR, day 14 EBC had a NPV of 82% and a PPV of 69%, while day 14 MRD had a NPV of 86% and a PPV of 49%. However, for predicting post-induction MRD, day 14 EBC had a NPV of 49% and a PPV of 15%, while day 14 MRD had a NPV of 71% and PPV of 74%. The correlation between day 14 and post-induction bone marrow aspiration is shown in Table 2. Bivariate analysis showed that achieving CR with negative MRD in post-induction bone marrow aspiration was associated with EBC (p<0.001) and negative MRD (p=0.04) at day 14 bone marrow aspiration. No statistically significances were observed based on marrow cellularity. A multivariate analysis using logistic regression showed that negative MRD by MFC at day 14 was the only independent predictor variable to achieve post-induction CR with negative MRD (OR 4.95% CI 1.0-15.9; p=0.04). CONCLUSION Patients showing EBC with negative MRD on day 14 bone marrow aspiration are more likely to achieve post-induction CR with negative MRD, with day 14 MRD by MFC being the only independent factor able to predict post-induction CR with negative MRD in our cohort. However, further prospective studies are needed to confirm our findings. Figure 1 Figure 1. Disclosures Martín-Rojas: Celgene-BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees. Kwon: Novartis, Celgene, Gilead, Pfizer: Consultancy, Honoraria.

scholarly journals Comparison of Acute Myeloid Leukemia Measurable Residual Disease Detection By Flow Cytometry in Peripheral Blood and Bone Marrow

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2729-2729
Author(s):  
Colin D. Godwin ◽  
Yi Zhou ◽  
Megan Othus ◽  
Carole M. Shaw ◽  
Kelda M. Gardner ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Board Of Directors ◽  
Correlation Coefficient ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Residual Disease ◽  
Spearman Correlation ◽  
Advisory Committees ◽  
Measurable Residual Disease ◽  
Acute Myeloid

BACKGROUND: The current recommendation against the need for bone marrow aspiration (BMA) in routine follow-of persons with acute myeloid leukemia (AML) in remission preceded the recognition that multiparameter flow cytometry (MFC) is a sensitive and specific means to detect imminent morphologic relapse. Given this recognition, we wondered whether BMA is now necessary, or if concordance between MFC results in peripheral blood (PB) and BMA is such as to make BMA unnecessary, at least for evaluation of measurable residual disease (MRD) by MFC. Previous studies have demonstrated a strong correlation between disease detection by MFC in PB and BMA. Here we examined 724 paired PB and BMA samples from 482 patients to further examine the concordance between PB and BMA blast detection by MFC, particularly among patients in morphologic remission. PATIENTS AND METHODS: We included adults in our institutional AML database, covering 2008-2018. Our Hematopathology database was queried to identify PB and BMA MFC sample pairs with samples considered "paired" if measured within one week of each other. If an individual had multiple pairs, all were included unless otherwise specified. Ten-color MFC was performed routinely on BMA aspirates with a panel of three antibody combinations, with the same antibody combinations applied to PB samples. When identified, the abnormal population was quantified as a percentage of the total CD45+ white cell events. Any level of residual disease was considered positive. Complete remission (CR) and relapse were defined according to the European LeukemiaNet 2017 classification. Relationship between PB and BMA blast % was measured using Spearman's Rank-Order Correlation. Relationship between PB and BMA samples identified as positive or negative is illustrated using 2 X 2 tables (Table 1). RESULTS: Considering all 724 sample pairs, the Spearman correlation coefficient between PB and BMA blast percentage was 0.93, and was 0.91 considering only the first sample pair for each individual patient (n= 482). 315 sample pairs were positive by PB, 97% of which were also positive by BMA while 95% of 409 pairs negative by PB were also negative by BMA. Similar results were seen considering only a patient's first pair. Restricting analysis to patients with pairs obtained between the dates of CR and relapse, the Spearman correlation coefficient was 0.82 with 91% of 35 cases positive in PB also positive in BMA; 93% of 114 pairs negative in PB were also negative in marrow. As a complementary means to compare pairs when AML burden was low, we examined only pairs where the BMA MFC showed <5% blasts. Here, the Spearman correlation coefficient between PB and BMA blasts was 0.83. 90% of 70 positive PB cases were also positive by BMA while 95% of 295 negative PB cases were also negative by BMA. Examining pairs taken from patients in morphologic remission immediately prior to undergoing hematopoietic cell transplant yielded a Spearman correlation coefficient of 0.92, with all 9 PB positive cases also being positive in BMA and 96% of PB negative cases being negative in BMA. CONCLUSIONS: This is the largest cohort of AML PB and BMA sample pairs analyzed by MFC to-date. The percentages of blasts measured in PB and BMA are strongly correlated. In the 365 pairs from patients with MRD-level disease, the predictive value of PB MFC positivity for BMA positivity was 90% (63/70) while the predictive value PB MFC negativity for BMA negativity was 95%. Disclosures Othus: Glycomimetics: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Gardner:Abbvie: Speakers Bureau. Walter:BioLineRx: Consultancy; BiVictriX: Consultancy; Boehringer Ingelheim: Consultancy; Boston Biomedical: Consultancy; Covagen: Consultancy; Daiichi Sankyo: Consultancy; Kite Pharma: Consultancy; New Link Genetics: Consultancy; Pfizer: Consultancy, Research Funding; Race Oncology: Consultancy; Seattle Genetics: Research Funding; Argenx BVBA: Consultancy; Aptevo Therapeutics: Consultancy, Research Funding; Jazz Pharmaceuticals: Consultancy; Astellas: Consultancy; Agios: Consultancy; Amgen: Consultancy; Amphivena Therapeutics: Consultancy, Equity Ownership.

scholarly journals A Prospective Phase 2 Study of Venetoclax and Low Dose Ara-C (VALDAC) to Target Rising Molecular Measurable Residual Disease and Early Relapse in Acute Myeloid Leukemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 1261-1261
Author(s):  
Ing S Tiong ◽  
Sun Loo ◽  
Emad Uddin Abro ◽  
Devendra Hiwase ◽  
Shaun Fleming ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Residual Disease ◽  
Phase 2 ◽  
Advisory Committees ◽  
Early Relapse ◽  
Phase 2 Study ◽  
Measurable Residual Disease ◽  
Acute Myeloid

Abstract Introduction Rising molecular measurable residual disease (MRD) is an arbiter of clinical relapse in acute myeloid leukemia (AML). Venetoclax (VEN) is active against IDH and NPM1 mutant (mt) AML as monotherapy (Konopleva et al, 2016 and Chua et al, 2020) and can yield MRD negative remission when combined with low dose ara-C (LDAC) in patients unfit for intensive chemotherapy (DiNardo and Tiong et al, 2020). In a retrospective study, we showed that VEN in combination with hypomethylating agents or LDAC could erase rising NPM1mt MRD in 6/7 cases (Tiong et al, 2020). We now present a prospective phase 2 study of VEN and LDAC in patients with molecular MRD failure or oligoblastic AML relapse. Methods This multicenter phase 2 study stratified patients into oligoblastic relapse (marrow blasts 5-15%; Group A), or molecular MRD failure (Group B) as defined by the European LeukemiaNet (ELN) recommendations (failure confirmed by 2 interval samples) (Schuurhuis et al, 2018). Patients received VEN 600 mg (days 1-28) and LDAC 20 mg/m 2 (days 1-10). Primary objectives were morphologic or MRD response (≥1 log reduction) in groups A and B, respectively. Key secondary objectives were allogeneic hematopoietic cell transplantation (allo-HCT) realization and relapse-free (RFS) and overall survival (OS). The study had Alfred Health ethics approval (196/19). NPM1mt and other fusion transcript levels (per 10 5 ABL) from bone marrow were analyzed by RT-qPCR, IDH1 and IDH2 by Bio-Rad TM droplet digital PCR. Results The study enrolled 32 patients, with 29 evaluable (cut-off date 15/7/21). The median age of the study population was 62 years; 79% had intermediate cytogenetic risk, 66% NPM1mt, 11% FLT3-ITD and 37% IDH1/IDH2 mt. Most received prior intensive chemotherapy (93%) and 2 (7%) allo-HCT in first remission. Median interval from AML diagnosis to study entry was 12.6 months (Table 1). After a median follow-up of 7.9 months, patients had received a median of 3 cycles (range 1-14) of VEN-LDAC, with 13 patients ongoing. The main reasons for treatment cessation were allo-HCT (n=10; 34%) or donor lymphocyte infusion (n=2; 7%), treatment failure (n=3) or an adverse event (n=1). Hematologic complete/incomplete response (CR/CRi) among 11 patients with oligoblastic relapse (group A) was 73% and included: CR (n=5, 45%) or CRi (n=3, 27%), with an additional patient with morphologic leukemia-free state and 2 patients with stable disease. Overall, across both groups, median RFS and OS were not reached, estimated at 78% and 91% at 1 year, respectively. Among 18 patients with molecular MRD failure (group B) treated with VEN+LDAC, molecular response (≥1 log reduction) was achieved in 72%, and the RFS and OS were estimated at 83% and 87% at 1 year, respectively. Analysis of a sub-group of patients with NPM1mt (n=18); 6 and 12 from Groups A and B, respectively revealed the median NPM1mt transcript level at study entry to be 8985 copies (IQR 826, 94,431). A molecular response was achieved in 14 (78%) patients, including 9 (50%) with complete molecular remission (CR MRD-), with most responses achieved within 2 cycles of therapy (Figure B). Treatment with VEN-LDAC was generally well tolerated, with 15 serious adverse events reported within the first 2 cycles, including infection (n=6; 19%) and febrile neutropenia (n=3; 9%). Only one subject discontinued treatment due to stroke. Conclusions In this prospective study, in patients with first oligoblastic relapse or MRD failure, VEN in combination with LDAC induced a high rate of molecular MRD remission that was rapidly achieved, resulting in a high rate of survival at 12-months (&gt;90%) and with low toxicity. Follow-up is ongoing to determine the durability of response. Treatment of patients with MRD or early clinical failure may represent an attractive clinical trial setting for investigation of novel, non-intensive AML therapies. This approach will be investigated in a future multi-arm, precision-based platform trial called INTERCEPT (Investigating Novel Therapy to Target Early Relapse and Clonal Evolution as Pre-emptive Therapy in AML). Figure 1 Figure 1. Disclosures Tiong: Servier: Consultancy, Speakers Bureau; Amgen: Speakers Bureau; Pfizer: Consultancy. Hiwase: Novartis: Membership on an entity's Board of Directors or advisory committees; AbbVie: Membership on an entity's Board of Directors or advisory committees. Fleming: Amgen Inc: Research Funding. Bajel: Amgen: Speakers Bureau; Abbvie, Amgen, Novartis, Pfizer: Honoraria. Fong: Amgen, BMS: Speakers Bureau; Amgen: Research Funding; AbbVie, Amgen, Novartis, Pfizer, Astellas: Honoraria. Wei: Celgene/BMS: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Agios: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Genentech: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Astellas: Membership on an entity's Board of Directors or advisory committees; Gilead: Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Macrogenics: Membership on an entity's Board of Directors or advisory committees; Servier: Membership on an entity's Board of Directors or advisory committees, Research Funding. OffLabel Disclosure: This presentation will discuss the use of venetoclax in targeting measurable residual disease and early relapse of acute myeloid leukemia.

scholarly journals Duplex Sequencing for Ultra-Low Frequency Measurable Residual Disease Detection in Adult Acute Myeloid Leukemia

Blood ◽  
2021 ◽  
Vol 138 (Supplement 1) ◽  
pp. 3475-3475
Author(s):  
Jacob Higgins ◽  
Megan Othus ◽  
Laura W. Dillon ◽  
Thomas H. Smith ◽  
Elizabeth Schmidt ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Residual Disease ◽  
Advisory Committees ◽  
Diagnostic Samples ◽  
Duplex Sequencing ◽  
Measurable Residual Disease ◽  
Acute Myeloid ◽  
Time Point

Abstract Background: The presence of measurable residual disease (MRD) is strongly associated with treatment outcomes in acute myeloid leukemia (AML). However, &gt; 20% of MRD negative cases (as assessed by flow cytometry) subsequently relapse. We sought to determine if ultrasensitive Duplex Sequencing (DS), which relies on double-stranded consensus-making to achieve an error rate below one-in-ten-million, yields better prognostic performance via molecular MRD detection. Methods: Retrospective targeted DNA sequencing of 29 genes recurrently mutated in adult AML was performed on paired diagnostic and remission bone marrow samples from patients enrolled on the SWOG trial S0106 (randomized 7+3 versus 7+3 + gemtuzumab ozogamicin (GO)). Patients were selected if they had remission samples with flow cytometry results (n=67). Non-error corrected sequencing was performed on diagnostic samples (average depth 279x) and DS was performed on remission samples (average duplex molecular depth 27,002x). For each patient, potential germline variants were identified and excluded from the analysis if the variant allele fraction (VAF) was ≥ 35% at both diagnosis and remission, or ≥ 40% at either time point and a gnomAD allele frequency ≥ 0.05. Somatic variants present at diagnosis were classified as potentially deleterious if computationally predicted as such and with a VAF ≥ 5% (≥ 1% for FLT3-ITD/NPM1 insertions). For analysis of residual disease in remission, we evaluated the following outcomes (events): overall survival (OS; death), relapse-free survival (RFS) and time to relapse (TTR; relapse with death a competing event). All outcomes were measured from date of morphologic remission to date of event, with patients without event censored at date of last contact. Associations between residual disease and outcomes were assessed using Cox regression models (cause-specific model for TTR). Results: The median age was 48 years (range 8-60). 32 patients were randomized to 7+3 and 30 to 7+3+GO. A total of 172 potentially deleterious variants were identified in the diagnostic samples. Variants had an average VAF of 31% (range 1.4-91.5%) at diagnosis and were detected in 23 of the 29 genes, with FLT3 being the most frequently mutated. Of the 67 patients analyzed, 93% (n=62) had at least one variant detected at diagnosis (median 2, range 0-9) and 68% (n=42) had at least one residual diagnostic variant also found in the remission sample. We defined the presence of DS MRD as non-DTA (DNMT3A, TET2, ASXL1) time-of-diagnosis mutations identified at the remission time point with a VAF &gt; 0.1% and/or an NPM1 VAF &gt; 0.01% (PMID:31860405). DS MRD was strongly associated with all outcomes, with hazard ratios (and 95% CI) for TTR: 7.1 (2.7-18.9); RFS: 4.9 (2.2-10.9) and OS: 5.1 (2.1-12.3). As a comparator, we correlated treatment outcomes with the results of a flow cytometry MRD assay previously carried out on the same samples during the S0106 trial. The prognostic association of flow MRD with TTR, RFS and OS was less strong (i.e., a smaller hazard ratio) than DS MRD, with TTR: 2.5 (0.9-6.7); RFS: 2.2 (0.9-5.4) and OS: 2.4 (1.0-6.1). RFS and TTR for DS MRD and flow cytometry are plotted below for the 62 patients with a variant detected at diagnosis. Comparing DS MRD with flow cytometry, discordance was found in 20 cases: 15 cases where DS was positive and flow negative, and 5 cases in the opposite direction. Among the 15 discordant cases with DS positive and flow negative, 9 relapsed and 2 died without relapse and 4 were alive without relapse at last contact. Among the 5 discordant cases with DS negative and flow positive, 1 relapsed, 1 died without relapse, and 3 were alive without relapse at last contact. Conclusions: Among the 67 patients evaluated in this prospectively collected study, the presence of MRD defined by DS was strongly associated with adverse disease outcomes. The vast majority of patients had at least one time-of-diagnosis mutation that could be tracked as a measure of MRD. When compared with flow cytometry, DS exhibited superior negative and positive predictive values for foretelling future relapse, although this could potentially reflect the historical version of the flow cytometry assay used. These findings suggest that DS is a powerful tool that could be used in patient management and for early treatment assessment in clinical trials. Figure 1 Figure 1. Disclosures Hourigan: Sellas: Research Funding. Radich: Amgen: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Genentech: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees.

scholarly journals Clonal Hematopoiesis and Its Implications for Flow Cytometric Assessment of Measurable Residual Disease in Patients with NPM1-mutated Acute Myeloid Leukemia

Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 38-39
Author(s):  
Sanam Loghavi ◽  
Courtney D. DiNardo ◽  
Koichi Takahashi ◽  
Rashmi Kanagal-Shamanna ◽  
Tomoyuki Tanaka ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Residual Disease ◽  
Advisory Committees ◽  
Clonal Hematopoiesis ◽  
Hla Dr ◽  
Measurable Residual Disease ◽  
Acute Myeloid ◽  
Myeloid Progenitors

INTRODUCTION: NPM1 mutations (NPM1mut) occur in ∼30% of acute myeloid leukemia (AML) and frequently co-occur with mutations in other genes including those attributed to clonal hematopoiesis (CH) including DNMT3A and TET2, among others. CH mutations may persist beyond attaining NPM1mut-negative remission. Persistent CH may be associated with immunophenotypic alterations in myeloid progenitors detected by flow cytometry (FC) which poses an interpretive challenge in assessment of measurable residual disease (MRD) by FC. The aim of this study was to characterize the immunophenotypic alterations associated with persistent CH in the setting of NPM1mut clearance and to determine their possible clinical or biologic significance. METHODS: The cohort included 67 consecutive patients (pts) with NPM1mut AML treated at our institution between 01/2017 and 11/2019. FC assessment for MRD was performed an eight-color panel using FACSCanto II instruments (BD Biosciences, San Diego, CA) with a sensitivity of 10-3 to 10-4. Whole bone marrow (BM) DNA was interrogated for mutations with an 81-gene myeloid next-generation sequencing (NGS) panel using an Illumina MiSeq sequencer (Illumina, Inc., San Diego, CA, USA) with a sensitivity: 1% variant allelic frequency (VAF). RESULTS: Pts included 26 men and 41 women with a median age of 64 (range, 19-84) years with newly diagnosed NPM1mut AML. AML blasts had the following immunophenotype at baseline: promyelocytic-like phenotype (CD34-, CD117+, HLA-DR-) in 18 (27%), aberrant myeloid CD34-/CD117+/HLA-DR+ in 15 (22%), aberrant myeloid CD34+ in 13 (19%), myelomonocytic in 11 (16%), and monocytic in 10 (15%) cases. All pts had additional co-mutations at baseline (Fig 1). The most frequently co-mutated genes were DNMT3A (58%) FLT3 (51%), TET2 (27%), IDH2 (24%), PTPN11 (19%), IDH1 (18%), NRAS (16%), and SRSF2 (12%). Pts were treated with intensive (35;52%) and non-intensive induction regimens (32; 48%) (Fig 1); 22 (33%) received an allogeneic hematopoietic stem cell transplant as post-remission consolidation. We compared FC and NGS results in follow-up samples in pts achieving NPM1mut negative remission with adequate data available for comparison (n=50). 13 (26%) pts cleared all mutations whereas 37 (74%) had persistent CH. The most common mutations in the setting of residual CH involved DNMT3A (70%), TET2 (27%), IDH2 (19%) and IDH1 (11%). Among 37 pts with residual CH, 19 (51%) had no phenotypic alterations detected by FC while 17 (49%) had myeloid progenitors with alterations in intensity of antigen expression (increased CD13, CD123, CD117 and/or decreased CD38) or deviation from normal maturation but not diagnostic for AML MRD (herein referred to as pre-leukemic (PL) phenotype); 1 sample was MRD+ by FC. Mutation VAF of ≥5% was significantly more common (p=0.008) in cases with FC PL+ (100%) vs cases with normal FC phenotype (63%). IDH2 and SRSF2 mutation were exclusively observed in PL+CH+ cases with the former being statistically significant when compared with the FC-normal group (p=0.016). PL phenotype by FC did not correlate with intensity of induction therapy (41% treated with intensive regimens vs 59% non-intensive). The CH+/PL+ cohort had more pts ≥60 yrs old (67%) but the difference was not significant. There was no significant association between PL+ and residual mutation count. Presence of PL+ phenotype was not associated with a shorter relapse-free survival (RFS) (median not reached for both groups). CONCLUSIONS: Post-remission clonal hematopoiesis in the setting of NPM1mut clearance is common, and may result in immunophenotypic changes in myeloid progenitors, posing interpretive challenges for MRD assessment by FC. These alterations may be attributable to specific CH characteristics, such as IDH2 and SRSF2 mutations and VAF, but are not associated with a shorter RFS and thus should not be interpreted as residual AML or considered a high-risk attribute. Additional studies in other AML subtypes are warranted to further delineate these changes and their clinical significance. Figure 1 Disclosures DiNardo: Daiichi Sankyo: Consultancy, Honoraria, Research Funding; Notable Labs: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy; Takeda: Honoraria; Jazz: Honoraria; ImmuneOnc: Honoraria; AbbVie: Consultancy, Honoraria, Research Funding; Syros: Honoraria; Agios: Consultancy, Honoraria, Research Funding; Calithera: Research Funding; MedImmune: Honoraria; Celgene: Consultancy, Honoraria, Research Funding. Short:AstraZeneca: Consultancy; Takeda Oncology: Consultancy, Honoraria, Research Funding; Amgen: Honoraria; Astellas: Research Funding. Kadia:JAZZ: Honoraria, Research Funding; Ascentage: Research Funding; Astra Zeneca: Research Funding; Incyte: Research Funding; Celgene: Research Funding; Novartis: Honoraria; Cyclacel: Research Funding; Genentech: Honoraria, Research Funding; Amgen: Research Funding; Abbvie: Honoraria, Research Funding; Cellenkos: Research Funding; Pulmotec: Research Funding; Astellas: Research Funding; BMS: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding. Konopleva:Sanofi: Research Funding; Eli Lilly: Research Funding; AstraZeneca: Research Funding; Rafael Pharmaceutical: Research Funding; Amgen: Consultancy; F. Hoffmann La-Roche: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding; Stemline Therapeutics: Consultancy, Research Funding; Kisoji: Consultancy; Reata Pharmaceutical Inc.;: Patents & Royalties: patents and royalties with patent US 7,795,305 B2 on CDDO-compounds and combination therapies, licensed to Reata Pharmaceutical; Ascentage: Research Funding; Calithera: Research Funding; Forty-Seven: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; Cellectis: Research Funding; Agios: Research Funding; Ablynx: Research Funding. Kantarjian:Adaptive biotechnologies: Honoraria; Aptitute Health: Honoraria; BioAscend: Honoraria; Delta Fly: Honoraria; Janssen: Honoraria; Oxford Biomedical: Honoraria; Ascentage: Research Funding; Daiichi-Sankyo: Honoraria, Research Funding; BMS: Research Funding; Immunogen: Research Funding; Jazz: Research Funding; Novartis: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Sanofi: Research Funding; Actinium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Honoraria, Research Funding; Amgen: Honoraria, Research Funding. Ravandi:Macrogenics: Research Funding; Celgene: Consultancy, Honoraria; AstraZeneca: Consultancy, Honoraria; Xencor: Consultancy, Honoraria, Research Funding; Jazz Pharmaceuticals: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding; Astellas: Consultancy, Honoraria, Research Funding; BMS: Consultancy, Honoraria, Research Funding; Orsenix: Consultancy, Honoraria, Research Funding.

scholarly journals Donor Cell Acute Myeloid Leukemia after Transplant for Follicular Lymphoma

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 5697-5697
Author(s):  
Lacey S. Williams ◽  
Catherine E. Lai
Keyword(s):  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Follicular Lymphoma ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Donor Cell ◽  
Cell Leukemia ◽  
Advisory Committees ◽  
Donor Cell Leukemia ◽  
Acute Myeloid

Donor cell leukemia is postulated to account for up to 5% of all leukemia "relapses" after hematopoietic stem cell transplant (SCT), though in many cases this is the first leukemia diagnosis for the patient if their transplant was for non-leukemia primary diseases. The rarity of the condition and heterogeneity of disease create challenges in diagnosis and management. In the present case, donor cell leukemia (DCL) developed in a 68-year-old female after allogeneic SCT 18 years earlier for follicular lymphoma. Only one other case of DCL after transplantation for follicular lymphoma has been reported (Boulton-Jones et al., Bone Marrow Transplantation, 2005). Furthermore, this case is atypical in that the presentation occurred many years after transplantation, since very few cases of DCL occur more than 15 years after original transplant. Case In 1993, the patient was diagnosed with stage IIIA follicular lymphoma at age 50. She achieved a complete remission with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) for 4 years. She relapsed in 1998 and received treatment with fludarabine and mitoxantrone. In 1999, she enrolled in a toxitumomab clinical trial (NCT00268203) but discontinued therapy secondary to side effects. Due to persistent disease, she proceeded with SCT and received EPOCH-F (etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and fludarabine) prior to allogeneic SCT from her brother in 2000 (6/6 HLA match), augmented with TH2 cells. She received graft versus host disease (GVHD) prophylaxis with cyclosporine, however her post transplant course was complicated by engraftment syndrome and gastrointestinal and skin GVHD. In 2019, she presented to hematology for evaluation of worsening chronic neutropenia and thrombocytopenia persistent for three years, noted during work-up for symptomatic cholelithiasis. Bone marrow biopsy revealed acute myeloid leukemia (AML) with a hypocellular marrow with 30% blasts and myelodysplasia related changes. Her cytogenetics showed 46XY, +1, der(1;7)(q10;p10)/47,sl,+8/46,XY. FISH analyses demonstrated deletion 7q31 D7S486 locus in 156/200 cells (78%). NGS panel showed IDH1 (VAF16%) and U2AF1 (VAF 26%) mutations. Based on cytogenetics and chimerism studies showing 100% donor, the patient was diagnosed with donor-derived AML secondary to allogeneic SCT from her brother. The brother currently has no known hematologic problems. The patient was treated with CPX-351 (liposomal cytarabine and daunorubicin) and achieved a complete remission, followed by consolidation with CPX-351. Given her complex cytogenetics and poor prognosis, the patient proceeded to non-myeloablative haploidentical peripheral blood SCT from her son, with post-transplant cyclophosphamide. She subsequently had complications of neutropenic fever and C. dificile colitis, with progressive colitis leading to her death on day 22 after SCT. Discussion Though cytogenetic and molecular studies along with functional status assist clinicians in treatment decisions for DCL patients, the benefits and risks of treatment remain difficult to balance for this unique subset of leukemia. Of patients that achieve remission for greater than 18 months, many undergo second allogeneic SCT, however a similar number of patients have remissions of at least 18 months treated with chemotherapy alone (Wiseman, Biology of Blood and Bone Marrow Transplantation, 2011). In 15 reported cases that went to SCT, approximately 50% lived longer than 12 months after their DCL diagnosis. Second allogeneic SCT is often favored after initial remission in patients with good performance status due to high risk for relapse. This case illustrates the challenge in management of donor cell leukemia, a rather rare entity with very few cases in the literature developing greater than 15 years after transplant. Limited robust evidence favoring a particular treatment supports the need for further prospective studies. Disclosures Lai: Agios: Membership on an entity's Board of Directors or advisory committees; Daiichi-Sankyo: Membership on an entity's Board of Directors or advisory committees; Jazz Pharma: Membership on an entity's Board of Directors or advisory committees; Jazz Pharma: Speakers Bureau; Astellas: Speakers Bureau.

scholarly journals p53 Mediated Bone Marrow Mesenchymal Stem Cell Expansion Supports Acute Myeloid Leukemia Development

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 523-523
Author(s):  
Rasoul Pourebrahimabadi ◽  
Zoe Alaniz ◽  
Lauren B Ostermann ◽  
Hung Alex Luong ◽  
Rafael Heinz Montoya ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Osteoblast Differentiation ◽  
Hematopoietic Cells ◽  
Advisory Committees ◽  
Equity Ownership ◽  
Mdm2 Inhibitor ◽  
Acute Myeloid

Acute myeloid leukemia (AML) is a heterogeneous disease that develops within a complex microenvironment. Reciprocal interactions between the bone marrow mesenchymal stem/stromal cells (BM-MSCs) and AML cells can promote AML progression and resistance to chemotherapy (Jacamo et al., 2014). We have recently reported that BM-MSCs derived from AML patients (n=103) highly express p53 and p21 compared to their normal counterparts (n=73 p&lt;0.0001) (Hematologica, 2018). To assess the function of p53 in BM-MSCs, we generated traceable lineage specific mouse models targeting Mdm2 or Trp53 alleles in MSCs (Osx-Cre;mTmG;p53fl/fl and Osx-Cre;mTmG;Mdm2fl/+) or hematopoietic cells (Vav-Cre;mTmG;p53fl/fl and Vav-Cre;mTmG;Mdm2fl/+). Homozygote deletion of Mdm2 (Osx-Cre;Mdm2fl/fl) resulted in death at birth and displayed skeletal defects as well as lack of intramedullary hematopoiesis. Heterozygote deletion of Mdm2 in MSCs was dispensable for normal hematopoiesis in adult mice, however, resulted in bone marrow failure and thrombocytopenia after irradiation. Homozygote deletion of Mdm2 in hematopoietic cells (Vav-Cre;Mdm2fl/fl) was embryonically lethal but the heterozygotes were radiosensitive. We next sought to examine if p53 levels in BM-MSCs change after cellular stress imposed by AML. We generated a traceable syngeneic AML model using AML-ETO leukemia cells transplanted into Osx-Cre;mTmG mice. We found that p53 was highly induced in BM-MSCs of AML mice, further confirming our findings in primary patient samples. The population of BM-MSCs was significantly increased in bone marrow Osx-Cre;mTmG transplanted with syngeneic AML cells. Tunnel staining of bone marrow samples in this traceable syngeneic AML model showed a block in apoptosis of BM-MSCs suggesting that the expansion of BM-MSCs in AML is partly due to inhibition of apoptosis. As the leukemia progressed the number of Td-Tomato positive cells which represents hematopoietic lineage and endothelial cells were significantly decreased indicating failure of normal hematopoiesis induced by leukemia. SA-β-gal activity was significantly induced in osteoblasts derived from leukemia mice in comparison to normal mice further supporting our observation in human leukemia samples that AML induces senescence of BM-MSCs. To examine the effect of p53 on the senescence associated secretory profile (SASP) of BM-MSCs, we measured fifteen SASP cytokines by qPCR and found significant decrease in Ccl4, Cxcl12, S100a8, Il6 and Il1b upon p53 deletion in BM-MSCs (Osx-Cre;mTmG;p53fl/fl) compared to p53 wildtype mice. To functionally evaluate the effects of p53 in BM-MSCs on AML, we deleted p53 in BM-MSCs (Osx-Cre;mTmG;p53fl/fl) and transplanted them with syngeneic AML-ETO-Turquoise AML cells. Deletion of p53 in BM-MSCs strongly inhibited the expansion of BM-MSCs in AML and resulted in osteoblast differentiation. This suggests that expansion of BM-MSCs in AML is dependent on p53 and that deletion of p53 results in osteoblast differentiation of BM-MSCs. Importantly, deletion of p53 in BM-MSCs significantly increased the survival of AML mice. We further evaluated the effect of a Mdm2 inhibitor, DS-5272, on BM-MSCs in our traceable mouse models. DS-5272 treatment of Osx-cre;Mdm2fl/+ mice resulted in complete loss of normal hematopoietic cells indicating a non-cell autonomous regulation of apoptosis of hematopoietic cells mediated by p53 in BM-MSCs. Loss of p53 in BM-MSCs (Osx-Cre;p53fl/fl) completely rescued hematopoietic failure following Mdm2 inhibitor treatment. In conclusion, we identified p53 activation as a novel mechanism by which BM-MSCs regulate proliferation and apoptosis of hematopoietic cells. This knowledge highlights a new mechanism of hematopoietic failure after AML therapy and informs new therapeutic strategies to eliminate AML. Disclosures Khoury: Angle: Research Funding; Stemline Therapeutics: Research Funding; Kiromic: Research Funding. Bueso-Ramos:Incyte: Consultancy. Andreeff:BiolineRx: Membership on an entity's Board of Directors or advisory committees; CLL Foundation: Membership on an entity's Board of Directors or advisory committees; NCI-RDCRN (Rare Disease Cliln Network): Membership on an entity's Board of Directors or advisory committees; Leukemia Lymphoma Society: Membership on an entity's Board of Directors or advisory committees; German Research Council: Membership on an entity's Board of Directors or advisory committees; NCI-CTEP: Membership on an entity's Board of Directors or advisory committees; Cancer UK: Membership on an entity's Board of Directors or advisory committees; Center for Drug Research & Development: Membership on an entity's Board of Directors or advisory committees; NIH/NCI: Research Funding; CPRIT: Research Funding; Breast Cancer Research Foundation: Research Funding; Oncolyze: Equity Ownership; Oncoceutics: Equity Ownership; Senti Bio: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Eutropics: Equity Ownership; Aptose: Equity Ownership; Reata: Equity Ownership; 6 Dimensions Capital: Consultancy; AstaZeneca: Consultancy; Amgen: Consultancy; Daiichi Sankyo, Inc.: Consultancy, Patents & Royalties: Patents licensed, royalty bearing, Research Funding; Jazz Pharmaceuticals: Consultancy; Celgene: Consultancy. OffLabel Disclosure: Mdm2 inhibitor-DS 5272

scholarly journals Venetoclax and Azacitidine for Older Newly Diagnosed Patients with Acute Myeloid Leukemia: A Single-Institution Pilot Study Using Measurable Residual Disease to Guide Therapy

Blood ◽  
2019 ◽  
Vol 134 (Supplement_1) ◽  
pp. 2638-2638 ◽  
Author(s):  
Amanda Winters ◽  
Jonathan A Gutman ◽  
Enkhtsetseg Purev ◽  
Brett M. Stevens ◽  
Shanshan Pei ◽  
...  
Keyword(s):  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Residual Disease ◽  
Refractory Disease ◽  
Advisory Committees ◽  
Ras Pathway ◽  
Measurable Residual Disease ◽  
Count Recovery

Background: Venetoclax (ven) was approved for older untreated acute myeloid leukemia (AML) patients due to high response rates and durable remissions. As a participating site in the dose escalation study, we observed deeper/more durable responses in some who received >400mg ven. We also noted 16/33 discontinued azacitidine (aza) after achieving a response; 9 relapsed and 7 remained in long term remission on ven only. Based on these observations, we designed a study that hypothesized: A)Higher initial doses of ven would allow deeper/more durable responses, and B)Multi modality high sensitivity measurable residual disease (MRD) testing could identify patients able to discontinue aza and remain on maintenance ven. Methods: This is an ongoing phase 2 study (NCT03466294) of 42 untreated AML patients ≥60 who decline/are ineligible for induction. Patients have adequate organ function and white blood cell counts <25x109/L (hydrea permitted). In cycle 1, patients receive aza 75mg/m2 on days (d) 1-7 and ven, escalated from 100 to 200 to 400 to 600mg on d 1-4. Ven continues at 600mg d 5-28 and bone marrow biopsies (BMBXs) are performed on d 8 and 28. Patients who achieve morphologic remission without count recovery have up to 14 days off therapy before subsequent cycles, with growth factor support; "upgraded" responses are recorded if count recovery occurs. Non responders discontinue or receive up to two additional cycles of aza and ven 600mg. Responders who remain MRD+ by multiparameter flow cytometry (MPFC, Hematologics) and/or digital droplet PCR (ddPCR) for as many identifiable diagnostic genes as possible also receive up to 2 additional cycles of aza and ven 600mg. MRD+ responders after 3 cycles continue aza and ven 400mg until toxicity/progression. Patients who experience MRD- responses at any time stop aza and continue ven 400mg daily (Fig 1). Results: 30 patients enrolled between May 2018 and July 2019; median age is 71 (60-88), 10% evolved from MDS and 10% and 73% had intermediate and unfavorable risk disease by ELN, respectively (Table 1). 732 adverse events (AEs) occurred; 46 (6%) were serious, the most common were neutropenic fever (37%) and pneumonia (13%). The most common >grade 2 related AEs were leukopenia (53%), thrombocytopenia (44%) and neutropenia (35%); there were no related grade 5 AEs. The overall response rate was 70% (21/30; CR=19, MLFS=2). Median number of cycles to achieve best response was 1. Significant blast reductions were seen on day 8; of the 28 with interpretable day 8 BMBXs, 10 achieved MLFS on day 8. 4 completed ≥1 cycle and were refractory. An additional 4 did not complete cycle 1: 1 died of disease and 3 elected to come off therapy (all subsequently died of disease). Four (19%) responders relapsed, after a median 180 days (27-279). With median follow up of 214 days, median response duration has not been reached. 10 patients died, after a median 65 days (29-256); 1/30 died within 30 days. Median overall survival has not been reached. Of the 26 who completed ≥1 cycle, 19 were MRD- by MPFC, including 18/19 who achieved CR. Of these 26, 3 were not monitored by ddPCR: for 2 patients this was due to the absence of detectable baseline mutations and for 1 patient it was due to refractory disease. The remaining 23 had ddPCR monitoring; 3 became MRD- by this modality (Fig 2). All 3 were also MRD- by MPFC and per protocol discontinued aza and initiated ven maintenance (Fig 1). MRD negativity by both parameters occurred after cycles 1, 2 and 3, respectively. One MRD- patient relapsed after 216 days; two remain in remission after 301 and 124 days. An additional 4 who achieved MRD+ responses discontinued aza at their insistence (and in violation of the protocol); 1 relapsed after 279 days, and 3 remain in ongoing remission. Univariate predictors of refractory disease were FAB M0/M1 (OR 0.070, p=0.02) and RAS pathway mutations (OR 14.25, p=0.02). Conclusions: Higher initial doses of ven are tolerated in this population. Blast reduction occurs quickly in many patients (day 8), for this low intensity regimen. Response rates are consistent with lower doses of ven. Very deep responses, as measured by highly sensitive MRD methods (MPFC and ddPCR are capable of sensitivity up to 0.02%), are attainable. Longer follow up time will determine if higher ven doses and MRD-driven decisions related to continuation of aza result in more durable responses. Increased maturation of blasts and RAS pathway mutations are predictors for refractory disease. Disclosures Lyle: Pfizer: Membership on an entity's Board of Directors or advisory committees; Daiichi Sankyo Incyte: Membership on an entity's Board of Directors or advisory committees; Agios: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Pollyea:Agios: Consultancy, Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celyad: Consultancy, Membership on an entity's Board of Directors or advisory committees; Diachii Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Forty-Seven: Consultancy, Membership on an entity's Board of Directors or advisory committees.

scholarly journals EZH2 Mutations and Impact on Clinical Outcome Analyzed in 1604 Patients with Acute Myeloid Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 1528-1528
Author(s):  
Sebastian Stasik ◽  
Jan Moritz Middeke ◽  
Michael Kramer ◽  
Christoph Rollig ◽  
Alwin Krämer ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Employment Equity ◽  
Advisory Committees ◽  
Mutational Status ◽  
Equity Ownership ◽  
Acute Myeloid

Abstract Purpose: The enhancer of zeste homolog 2 (EZH2) is a histone methyltransferase and key epigenetic regulator involved in transcriptional repression and embryonic development. Loss of EZH2 activity by inactivating mutations is associated with poor prognosis in myeloid malignancies such as MDS. More recently, EZH2 inactivation was shown to induce chemoresistance in acute myeloid leukemia (AML) (Göllner et al., 2017). Data on the frequency and prognostic role of EZH2-mutations in AML are rare and mostly confined to smaller cohorts. To investigate the prevalence and prognostic impact of this alteration in more detail, we analyzed a large cohort of AML patients (n = 1604) for EZH2 mutations. Patients and Methods: All patients analyzed had newly diagnosed AML, were registered in clinical protocols of the Study Alliance Leukemia (SAL) (AML96, AML2003 or AML60+, SORAML) and had available material at diagnosis. Screening for EZH2 mutations and associated alterations was done using Next-Generation Sequencing (NGS) (TruSight Myeloid Sequencing Panel, Illumina) on an Illumina MiSeq-system using bone marrow or peripheral blood. Detection was conducted with a defined cut-off of 5% variant allele frequency (VAF). All samples below the predefined threshold were classified as EZH2 wild type (wt). Patient clinical characteristics and co-mutations were analyzed according to the mutational status. Furthermore, multivariate analysis was used to identify the impact of EZH2 mutations on outcome. Results: EZH2-mutations were found in 63 of 1604 (4%) patients, with a median VAF of 44% (range 6-97%; median coverage 3077x). Mutations were detected within several exons (2-6; 8-12; 14-20) with highest frequencies in exons 17 and 18 (29%). The majority of detected mutations (71% missense and 29% nonsense/frameshift) were single nucleotide variants (SNVs) (87%), followed by small indel mutations. Descriptive statistics of clinical parameters and associated co-mutations revealed significant differences between EZH2-mut and -wt patients. At diagnosis, patients with EZH2 mutations were significantly older (median age 59 yrs) than EZH2-wt patients (median 56 yrs; p=0.044). In addition, significantly fewer EZH2-mut patients (71%) were diagnosed with de novo AML compared to EZH2-wt patients (84%; p=0.036). Accordingly, EZH2-mut patients had a higher rate of secondary acute myeloid leukemia (sAML) (21%), evolving from prior MDS or after prior chemotherapy (tAML) (8%; p=0.036). Also, bone marrow (and blood) blast counts differed between the two groups (EZH2-mut patients had significantly lower BM and PB blast counts; p=0.013). In contrast, no differences were observed for WBC counts, karyotype, ECOG performance status and ELN-2017 risk category compared to EZH2-wt patients. Based on cytogenetics according to the 2017 ELN criteria, 35% of EZH2-mut patients were categorized with favorable risk, 28% had intermediate and 37% adverse risk. No association was seen with -7/7q-. In the group of EZH2-mut AML patients, significantly higher rates of co-mutations were detected in RUNX1 (25%), ASXL1 (22%) and NRAS (25%) compared to EZH2-wt patients (with 10%; 8% and 15%, respectively). Vice versa, concomitant mutations in NPM1 were (non-significantly) more common in EZH2-wt patients (33%) vs EZH2-mut patients (21%). For other frequently mutated genes in AML there was no major difference between EZH2-mut and -wt patients, e.g. FLT3ITD (13%), FLT3TKD (10%) and CEBPA (24%), as well as genes encoding epigenetic modifiers, namely, DNMT3A (21%), IDH1/2 (11/14%), and TET2 (21%). The correlation of EZH2 mutational status with clinical outcomes showed no effect of EZH2 mutations on the rate of complete remission (CR), relapse free survival (RFS) and overall survival (OS) (with a median OS of 18.4 and 17.1 months for EZH2-mut and -wt patients, respectively) in the univariate analyses. Likewise, the multivariate analysis with clinical variable such as age, cytogenetics and WBC using Cox proportional hazard regression, revealed that EZH2 mutations were not an independent risk factor for OS or RFS. Conclusion EZH mutations are recurrent alterations in patients with AML. The association with certain clinical factors and typical mutations such as RUNX1 and ASXL1 points to the fact that these mutations are associated with secondary AML. Our data do not indicate that EZH2 mutations represent an independent prognostic factor. Disclosures Middeke: Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees. Rollig:Bayer: Research Funding; Janssen: Research Funding. Scholl:Jazz Pharma: Membership on an entity's Board of Directors or advisory committees; Abbivie: Other: Travel support; Alexion: Other: Travel support; MDS: Other: Travel support; Novartis: Other: Travel support; Deutsche Krebshilfe: Research Funding; Carreras Foundation: Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees. Hochhaus:Pfizer: Research Funding; Incyte: Research Funding; Novartis: Research Funding; Bristol-Myers Squibb: Research Funding; Takeda: Research Funding. Brümmendorf:Janssen: Consultancy; Takeda: Consultancy; Novartis: Consultancy, Research Funding; Merck: Consultancy; Pfizer: Consultancy, Research Funding. Burchert:AOP Orphan: Honoraria, Research Funding; Bayer: Research Funding; Pfizer: Honoraria; Bristol Myers Squibb: Honoraria, Research Funding; Novartis: Research Funding. Krause:Novartis: Research Funding. Hänel:Amgen: Honoraria; Roche: Honoraria; Takeda: Honoraria; Novartis: Honoraria. Platzbecker:Celgene: Research Funding. Mayer:Eisai: Research Funding; Novartis: Research Funding; Roche: Research Funding; Johnson & Johnson: Research Funding; Affimed: Research Funding. Serve:Bayer: Research Funding. Ehninger:Cellex Gesellschaft fuer Zellgewinnung mbH: Employment, Equity Ownership; Bayer: Research Funding; GEMoaB Monoclonals GmbH: Employment, Equity Ownership. Thiede:AgenDix: Other: Ownership; Novartis: Honoraria, Research Funding.

scholarly journals Genetic Dissection of p53 Driven Senescence of Bone Marrow Mesenchymal Cells in Acute Myeloid Leukemia

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2625-2625
Author(s):  
Rasoul Pourebrahim ◽  
Peter P. Ruvolo ◽  
Steven M. Kornblau ◽  
Carlos E. Bueso-Ramos ◽  
Michael Andreeff
Keyword(s):  
Bone Marrow ◽  
Acute Myeloid Leukemia ◽  
Board Of Directors ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Bone Marrow Mscs ◽  
Advisory Committees ◽  
Equity Ownership ◽  
Bone Marrow Mesenchymal Cells ◽  
Acute Myeloid

Abstract Acute myeloid leukemia (AML) is a genetically heterogeneous malignancy characterized by bone marrow infiltration of abnormally proliferating leukemic blasts which results in fatal anemia, bleeding and infectious complications due to compromised normal hematopoiesis. Patients with complete remission (CR) but incomplete blood cell count recovery (CRi) have significantly shorter survival compared to CR patients. Although there is a correlation between CRi and minimal residual disease (MRD), the two variables were shown to be independent risk factors for relapse development (1). The mechanism by which AML induces bone marrow failure in patients is largely unknown. Here, we demonstrate that AML derived MSCs highly express p53 and p21 proteins and are more senescent compared to their normal age-matched controls as demonstrated by high β-galactosidase staining (figure 1. A, B&C). Emerging evidence indicates that the aging of endosteal niche cells results in lower reconstitution potential of hematopoietic stem cells (2). To functionally evaluate the effects of AML on bone marrow MSCs, we utilized a murine leukemia model of the AML microenvironment. We transplanted Osx-Cre;mTmG mice with AML cells and compared the senescence of MSCs in normal bone marrow (Figure 1.D) with AML (Figure 1.E). Consistent with our initial findings in human, AML strongly induced senescence of osteoblasts. This suggests that AML suppresses normal hematopoiesis by inducing senescence in the hematopoietic niche. To address the role of p53 signaling in senescence of MSCs we generated a traceable conditional p53 gain/loss model specifically in bone marrow MSCs using Osx-Cre;mTmG; Mdm2fl/+ and Osx-Cre;mTmG;p53fl/fl mice respectively (Figure 1.F). Deletion of p53 in bone marrow MSCs resulted in an increased population of osteoblasts (GFP+) in Osx-Cre;mTmG;p53fl/fl mice in comparison to Osx-Cre;mTmG mice suggesting that p53 loss in osteoblasts inhibits senescence of osteoblasts. In order to evaluate p53 activity after recombination of p53fl alleles in the osteoblasts, we isolated MSCs from bone marrows and analyzed the expression of p21.P21 was significantly down regulated in osteoblasts (GFP+) derived from Osx-Cre;mTmG;p53fl/fl mice whereas its expression in the hematopoietic cells from same tissue (tdTomato+) remained comparable to p53 wild type suggesting that p21 as the master regulator of senescence is regulated by p53 in bone marrow mesenchymal cells. To evaluate the effect of p53 loss in osteoblasts and its impact on hematopoietic cells, we isolated the GFP+ cells (osteoblasts) and RFP + cells (hematopoietic) by FACS. Senescent cells, non-cell autonomously, modulate the bone marrow microenvironment through the senescence-associated secretory phenotype (SASP). We analyzed the expression of fifteen SASP cytokines by QPCR. Deletion of p53 in bone marrow mesenchymal cells strongly abrogated the expression of several SASP cytokines. Interestingly several Notch target genes such as Hey1 and Hey2 were highly induced in MSCs following p53 deletion suggesting a role for Notch signaling in hematopoietic failure following AML induced MSCs senescence. Our data suggest that AML induces senescence of endosteal niche resulting in hematopoietic failure. These findings contribute to our understanding of the role of p53 in leukemia MSCs and could have broad translational significance for the treatment of hematopoietic failure in patients with AML.Chen X, et al. (2015) Relation of clinical response and minimal residual disease and their prognostic impact on outcome in acute myeloid leukemia. J Clin Oncol 33(11):1258-1264.Li J, et al. (2018) Murine hematopoietic stem cell reconstitution potential is maintained by osteopontin during aging. Sci Rep 8(1):2833. Disclosures Andreeff: Astra Zeneca: Research Funding; Daiichi-Sankyo: Consultancy, Patents & Royalties: MDM2 inhibitor activity patent, Research Funding; United Therapeutics: Patents & Royalties: GD2 inhibition in breast cancer ; Celgene: Consultancy; Eutropics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Research Funding; Oncoceutics: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; SentiBio: Equity Ownership; Aptose: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Oncolyze: Equity Ownership; Jazz Pharma: Consultancy; Reata: Equity Ownership.

scholarly journals Dissecting Signaling Network Responses to PAK4 Allosteric Modulators (PAMs) in Cell Subsets within Primary Human Acute Myeloid Leukemia Samples

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 3686-3686
Author(s):  
Paul Brent Ferrell ◽  
William Senapedis ◽  
Alexander Cook ◽  
Erkan Baloglu ◽  
Yosef Landesman ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Board Of Directors ◽  
Cell Lines ◽  
Myeloid Leukemia ◽  
Research Funding ◽  
Leukemia Stem Cells ◽  
Allosteric Modulators ◽  
Advisory Committees ◽  
Acute Myeloid

Abstract Background: Acute myeloid leukemia (AML) is the most common acute leukemia in adults and has a poor outcome with limited treatment options in patients with relapsed or resistant disease. Therapy resistance in AML is likely related to the inadequacy of therapy within leukemia cell subsets, including leukemia stem cells (LSCs). The p21-activated kinase (PAK) family of proteins was shown to be overexpressed in cancer cells and to play a key role in proliferation, survival, and maintenance of cellular structure. The series of orally bioavailable PAK4 allosteric modulators (PAM) have previously been shown to have activity in hematological cancer cell lines, including those derived from acute myeloid leukemia (AML) (Senapedis et al. Blood124, 2208-2208). Understanding how therapies target cellular subsets within primary patient samples could aid drug development by revealing any subset specific drug effects. In this project, we studied the effects of p21-activated kinase 4 (PAK4) modulation in AML samples. PAK4 modulation has been shown to have significant effects on many intracellular signaling pathways, including PI3K/AKT, MAPK/ERK and WNT/β-catenin pathways (Senapedis et al. Blood124, 2208-2208). It is unknown whether PAMs will have similar activity in primary leukemia cells. Likewise, it is currently unclear to what extent PAMs will differentially impact primary cell subsets including leukemia stem cells and non-malignant cell subsets that may be critical to recovery of bone marrow functions. We have previously shown that the single cell biology platform of flow cytometry is well-suited for dissecting clinically relevant signaling network mechanisms in primary human AML (Irish et al. Cell, 118(2):217-28). Methods: Flow cytometry was used to dissect the impact of an orally bioavailable PAM in AML cell lines and primary patient tissue. Cell lines chosen for this study included NRAS mutant KG-1 and Kasumi-1, which carry t(8;21) and express the AML1:ETO fusion protein. Primary AML biopsies were acquired from bone marrow or blood prior to any treatment and patients were identified and consented for this study according to a local Institutional Review Board-approved protocol. AML tissue samples were viably cryopreserved and then assayed ex vivo. Established protocols were used for phospho-specific flow cytometry, fluorescent cell barcoding, and data analysis in Cytobank (Irish et al. Cell, 118(2):217-28, Doxie and Irish, Curr Top Microbiol Immunol. 377:1-21). Results: Differential effects of PAK4 inhibition were observed between cell lines and among cell subsets from AML patient bone marrow. In leukemia cell lines and patient samples, p-ERK and p-S6 showed marked inhibition via PAM, though degree of inhibition varied. In AML patient samples, PAMs blocked signaling responses in p-ERK specifically in AML blasts, but spared normal CD45hi mononuclear cells (0.88 vs. 0.29-fold reduction (arcsinh scale) in p-ERK at 10 nM). Within the AML blast population, CD34+ CD38- and CD34+ CD38+ AML subsets showed similar PAM dose response via p-ERK. Conclusions: Single cell analysis effectively distinguishes effects of PAK4 inhibition via a series of allosteric modulators of PAK4 (PAMs) on leukemia and non-leukemia subsets in the same sample. PAM reduced immediate p-ERK and p-S6 levels in primary leukemia and cell lines. Notably, inhibition in various subsets within human AML was successfully measured by phospho-flow cytometry. Signaling changes in p-ERK were minimal within non-leukemic mature CD45+ mononuclear cells found in primary patient biopsies. Analysis of CD34+ CD38- cells indicates that PAMs could have activity within leukemia stem cells, and, at least, effect the AML progenitors. These findings support further investigation into the mechanism of action and treatment potential of PAMs in AML. Disclosures Senapedis: Karyopharm Therapeutics, Inc.: Employment, Patents & Royalties. Baloglu:Karyopharm Therapeutics Inc.: Employment, Equity Ownership. Landesman:Karyopharm: Employment. Irish:Novartis: Honoraria; Cytobank, Inc.: Equity Ownership, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Research Funding; InCyte: Research Funding. Savona:Gilead: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding.

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