scholarly journals EZH2 in Myeloid Malignancies

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1639 ◽  
Author(s):  
Jenny Rinke ◽  
Andrew Chase ◽  
Nicholas C. P. Cross ◽  
Andreas Hochhaus ◽  
Thomas Ernst

Our understanding of the significance of epigenetic dysregulation in the pathogenesis of myeloid malignancies has greatly advanced in the past decade. Enhancer of Zeste Homolog 2 (EZH2) is the catalytic core component of the Polycomb Repressive Complex 2 (PRC2), which is responsible for gene silencing through trimethylation of H3K27. EZH2 dysregulation is highly tumorigenic and has been observed in various cancers, with EZH2 acting as an oncogene or a tumor-suppressor depending on cellular context. While loss-of-function mutations of EZH2 frequently affect patients with myelodysplastic/myeloproliferative neoplasms, myelodysplastic syndrome and myelofibrosis, cases of chronic myeloid leukemia (CML) seem to be largely characterized by EZH2 overexpression. A variety of other factors frequently aberrant in myeloid leukemia can affect PRC2 function and disease pathogenesis, including Additional Sex Combs Like 1 (ASXL1) and splicing gene mutations. As the genetic background of myeloid malignancies is largely heterogeneous, it is not surprising that EZH2 mutations act in conjunction with other aberrations. Since EZH2 mutations are considered to be early events in disease pathogenesis, they are of therapeutic interest to researchers, though targeting of EZH2 loss-of-function does present unique challenges. Preliminary research indicates that combined tyrosine kinase inhibitor (TKI) and EZH2 inhibitor therapy may provide a strategy to eliminate the residual disease burden in CML to allow patients to remain in treatment-free remission.

2020 ◽  
Vol 4 (13) ◽  
pp. 3034-3040 ◽  
Author(s):  
Philippe Rousselot ◽  
Clémence Loiseau ◽  
Marc Delord ◽  
Jean Michel Cayuela ◽  
Marc Spentchian

Abstract Treatment-free remission (TFR) is an opportunity for patients with chronic myeloid leukemia (CML). Reported cumulative incidence curves of molecular recurrence (MRec) arbor a 2-phase shape with mainly early events, but also some late events (late MRec [LMRec]). Having discontinued our first patient in 2004, we have access to a prolonged follow-up, enabling us to characterize these late events. Over 15 years, 128 patients from our institution were registered in the Stop Imatinib (STIM; A Study for Tyrosine Kinase Inhibitors Discontinuation [A-STIM]) trial. MRec was defined by the loss of major molecular response (BCR-ABL1IS >0.1%). At the first TFR attempt, patients had been taking a tyrosine kinase inhibitor for a median of 7.1 years and in BCR-ABL1IS ≤0.01% (MR4) for a median of 4 years. The median follow-up of patients in TFR was 6.5 years. The TFR rate was estimated to be 45.6% after 7 years. For 9/65 (14%) patients experiencing MRec, recurrence occurred after 2 years in TFR (median, 3.6 years). The residual rate of MRec after 2 years was estimated to be 18%. The probability of remaining in TFR was 65.4% for patients having experienced fluctuations of their minimal residual disease (MRD) (at least 2 consecutive measurements BCR-ABL1IS >0.0032% or loss of MR4), whereas it was 100% for those with stable MRD (P = .003). After 2 years in TFR, we observed an 18% residual rate of LMRec. These late events represent 14% of all MRec and occur in patients with fluctuating MRD measurements. A long-term molecular follow-up therefore remains mandatory for CML patients in TFR. The A-STIM study was registered at www.clinicaltrials.gov as #NCT02897245.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
K. A. Mundt ◽  
L. D. Dell ◽  
P. Boffetta ◽  
E. M. Beckett ◽  
H. N. Lynch ◽  
...  

Abstract Introduction Although myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), myeloproliferative neoplasms (MPN) – including chronic myeloid leukemia (CML) – and myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are largely clinically distinct myeloid malignancies, epidemiological studies rarely examine them separately and often combine them with lymphoid malignancies, limiting possible etiological interpretations for specific myeloid malignancies. Methods We systematically evaluated the epidemiological literature on the four chemical agents (1,3-butadiene, formaldehyde, benzene, and tobacco smoking, excluding pharmaceutical, microbial and radioactive agents, and pesticides) classified by the International Agency for Research on Cancer as having sufficient epidemiological evidence to conclude that each causes “myeloid malignancies.” Literature searches of IARC Monographs and PubMed identified 85 studies that we critically assessed, and for appropriate subsets, summarized results using meta-analysis. Results Only two epidemiological studies on 1,3-butadiene were identified, but reported findings were inadequate to evaluate specific myeloid malignancies. Studies on formaldehyde reported results for AML and CML – and not for MDS or MPN – but reported no increased risks. For benzene, several specific myeloid malignancies were evaluated, with consistent associations reported with AML and MDS and mixed results for CML. Studies of tobacco smoking examined all major myeloid malignancies, demonstrating consistent relationships with AML, MDS and MPN, but not with CML. Conclusions Surprisingly few epidemiological studies present results for specific myeloid malignancies, and those identified were inconsistent across studies of the same exposure, as well as across chemical agents. This exercise illustrates that even for agents classified as having sufficient evidence of causing “myeloid malignancies,” the epidemiological evidence for specific myeloid malignancies is generally limited and inconsistent. Future epidemiological studies should report findings for the specific myeloid malignancies, as combining them post hoc – where appropriate – always remains possible, whereas disaggregation may not. Furthermore, combining results across possibly discrete diseases reduces the chances of identifying important malignancy-specific causal associations.


Leukemia ◽  
2019 ◽  
Vol 34 (4) ◽  
pp. 1052-1061 ◽  
Author(s):  
Ilaria S. Pagani ◽  
Phuong Dang ◽  
Verity A. Saunders ◽  
Randall Grose ◽  
Naranie Shanmuganathan ◽  
...  

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3921-3921
Author(s):  
Yuichiro Ono ◽  
June Takeda ◽  
Hayato Maruoka ◽  
Yasuhiro Kazuma ◽  
Nobuhiro Hiramoto ◽  
...  

Abstract Background About 70-80% of adult patients (pts) with acute myeloid leukemia (AML) achieve complete remission (CR); however, around a half of them experience a relapse. For the purpose of creating accurate decision-making process of post-consolidation strategy, stratification system using karyotype and recurrent gene mutations have been widely utilized. As is confirmed in childhood acute lymphocytic leukemia, however, the information of minimal residual disease (MRD) status would substantially improve the reliance of decision-making process of adult AML pts. Unfortunately, approximately a half of AML patients lack molecular targets suitable for MRD monitoring. The aims of this study are to evaluate the applicability of MRD detection using multiparametric flow cytometry (MPFC) and to estimate the impact of MRD measured with MPFC at the end of consolidation therapy in improving decision-making process. Patients and Methods We retrospectively studied 81 consecutive pts with newly diagnosed AML who received induction therapies and achieved CR in our institute between January 2007 and March 2013. Pts with acute promyelocytic leukemia were excluded. We routinely analyzed the bone marrow specimens with MPFC for the detection of leukemia-associated immunophenotypes (LAIPs) at diagnosis. Since April 2010, RT-PCR assay examined FLT3-ITD mutation in the same specimens. In pts who had traceable LAIPs, the relationships of the levels of MRD at the end of consolidation therapy with relapse free survival were analyzed. Positive MRD was defined as the detection of 0.2% and more LAIPs-positive cells with MPFC. We compared two patient groups: those with MRD at the end of consolidation (MRDp group) and those without (MRDn group). Relapse-free survival (RFS) was analyzed using the Kaplan-Meier method and the log-rank test was used for comparison between each group. A multivariate Cox regression analysis for RFS was fit to assess the effect of the followings: age at diagnosis (≥ vs. < 65 years old), the number of induction regimens required for achieving CR (≥ vs. < 2 times), cytogenetic risk groups of SWOG (unfavorable vs. favorable/intermediate). Results In 57 / 81 pts, MPFC could detect LAIPs in the bone marrow specimens at diagnosis (70.4% of all subjects; 15-82 years-old; follow-up time [median] 98-2211[517] days). FLT-ITD mutations were found in 13 pts, but not in 39 pts (the remaining 5 pts were not examined). The rate of detection of LAIPs with 6-color MPFC was significantly superior to 3-color MPFC (82.1% vs. 61.0%, p<0.05). Induction chemotherapies the pts received were anthracyclin-containing regimens, such as idarubicin and cytarabin (3+7), in 52 pts (91.2%), low-dose cytarabin-based regimen in 4 pts (7.0%) and azacitidine in 1 pt. (1.8%). The MRDp and the MRDn groups were comprised of 20 and 37 pts (35.1% and 64.9%) , respectively. One-year RFS of the MRDp group was significantly inferior to the MRDn group (28.3% vs. 75.2%; log-rank p<0.0005). In the multivariable analysis using the model above, MRD positivity at the end of consolidation remains a significant predictor (HR, 2.93, 95% CI 1.16-7.45, p<0.05). In addition, the 1-year RFS in the MRDp group with FLT-ITD was significantly shorter than that in the MRDp group without FLT3-ITD (0% vs. 47.6% with positive and negative FLT3-ITD, log-rank p<0.05). In the MRDn group, however, the negative impact of FLT3-ITD was not documented (85.7% vs. 69.3% with positive and negative FLT3-ITD, log-rank p=0.954). Conclusion Our retrospective study confirmed that LAIPs as MRD targets were applicable to the majority of pts with AML; MRD positivity measured with LAIPs was a promising predictor for early relapses at the end of consolidation, as was previously reported. When combined with FLT-ITD status, it might become a more sensitive prognostic factor. Disclosures: Takahashi: celgene: Research Funding.


2017 ◽  
Vol 93 (3) ◽  
pp. 330-338 ◽  
Author(s):  
Geoffroy Venton ◽  
Frédéric Courtier ◽  
Aude Charbonnier ◽  
Evelyne D'incan ◽  
Colombe Saillard ◽  
...  

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2296-2296
Author(s):  
Yue Lu ◽  
Tong Wu ◽  
Yan-Li Zhao ◽  
Xing-Yu Cao ◽  
De-Yan Liu ◽  
...  

Abstract Introduction: Cytogenetic abnormality is considered to be an independent prognostic factor in newly diagnosed acute myeloid leukemia (AML). However, recent studies have demonstrated that acquired gene mutations also play an important role in the pathogenesis and prognosis of AML. It has been well known that minimal residual disease (MRD) pre-conditioning has remarkable impact on disease-free survival (DFS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in acute lymphoblastic leukemia, but the effect of MRD pre-transplant on allo-HSCT in AML is still unclear. Objective: In present study, the effect of NCCN risk stratification which has integrated gene mutations into cytogenetics as well as MRD pre-transplant on DFS after allo-HSCT in AML was studied in order to learn whether risk-directed conditioning and prevention of relapse are needed. Methods: Between April 2012 and March 2015, consecutive 258 patients with AML in complete remission (CR) (186 cases in CR1 and 72 cases in CR2) who underwent allo-HSCT in our hospital were analyzed retrospectively. The median age was 25 (1.8-64) years. Male (M) to female (F) was 147:111. The median disease course was 6 (1-51) months. According to 2015-NCCN risk stratification, 63 (24.4%) cases were in low risk, 112 (43.4%) cases in intermediated risk, and 83 (32.2%) cases in high risk. MRD in bone marrow pre-conditioning was detected by eight-color flow cytometry. Results: With the median follow up 18 (5-41) months, overall 2-year DFS was78.0%. No significant difference in DFS was found among low-risk (78.6%), intermediated-risk (76.0%) and high-risk (80.3%) patients (P=0.886). 205 (79.5%) cases were MRD- and 53 (20.5%) cases were MRD+ before conditioning. DFS after transplant in MRD+ patients was significant lower than that in MRD- patients(65.0% vs. 81.4%, P=0.003). Univariate analysis showed that DFS was not associated with patient age (≤14years vs.>14years, P=0.292), disease course before HSCT (≤6 months vs.>6months, P=0.532), WBC counts at diagnosis (≤50×109/L vs.>50×109/L, P=0.120), CBC recovery pre-HSCT (yes vs. no, P=0.664), disease status (CR1 vs. CR2, P=0.201), extramedullary leukemia before transplant (yes vs. no, P=0.532), conditioning regimen (BUCy/Flu-based vs. TBICy/Flu-based, P=0.753), donor type (identical sibling vs. unrelated vs. haploidentical, P=0.743), donor-recipient gender (M-M vs. M-F vs. F-M vs. F-F, P=0.245), donor-recipient blood type (compatibility vs. major incompatibility vs. minor incompatibility vs. major and minor incompatibility, P=0.402), mononuclear cells infused (≤8×108/kg vs.>8×108/kg, P=0.583), CD34+ cells infused (≤4×106/kg vs.>4×106/kg, P=0.946), and CD3+ cells infused (≤1.6×108/kg vs.>1.6×108/kg, P=0.143). DFS was significant lower in the patients with secondary AML (79.4% in primary AML vs. 53.5% in secondary AML, P=0.006) and MRD+ cases before transplant (81.4% in MRD- vs. 65.0% in MRD+, P=0.003). Accumulative non-relapse mortality (NRM) was significant higher in secondary AML (11.7% in primary AML vs. 33.3% in secondary AML, P=0.004) and MRD+ patients (10.5% in MRD- vs. 21.9% in MRD+, P=0.010). Accumulative relapse rate was significant higher in CR2 cases (8.0% in CR1 vs. 17.5% in CR2, P=0.046). Multivariate analysis showed that MRD pre-HSCT was the only impact factor on DFS and NRM with higher DFS (P=0.020) and lower NRM (P=0.045) in MRD- cases. Conclusions: Allo-HSCT has attenuated the influence of cytogenetics and gene mutations on DFS in AML. Secondary AML has lower DFS and higher NRM. Although disease status (CR1 vs. CR2) has no significant influence on DFS, relapse rate in CR2 is higher than that in CR1. MRD pre-conditioning was a key impact factor on DFS after allo-HSCT in AML but not conditioning regimen and donor type. Disclosures No relevant conflicts of interest to declare.


Leukemia ◽  
2020 ◽  
Vol 34 (10) ◽  
pp. 2635-2647
Author(s):  
Oliver Parting ◽  
Samantha Langer ◽  
Maja Kim Kuepper ◽  
Caroline Wessling ◽  
Shaoguang Li ◽  
...  

Abstract Despite the successes achieved with molecular targeted inhibition of the oncogenic driver Bcr-Abl in chronic myeloid leukemia (CML), the majority of patients still require lifelong tyrosine kinase inhibitor (TKI) therapy. This is primarily caused by resisting leukemic stem cells (LSCs), which prevent achievement of treatment-free remission in all patients. Here we describe the ITIM (immunoreceptor tyrosine-based inhibition motif)-containing Fc gamma receptor IIb (FcγRIIb, CD32b) for being critical in LSC resistance and show that targeting FcγRIIb downstream signaling, by using a Food and Drug Administration-approved BTK inhibitor, provides a successful therapeutic approach. First, we identified FcγRIIb upregulation in primary CML stem cells. FcγRIIb depletion caused reduced serial re-plaiting efficiency and cell proliferation in malignant cells. FcγRIIb targeting in both a transgenic and retroviral CML mouse model provided in vivo evidence for successful LSC reduction. Subsequently, we identified BTK as a main downstream mediator and targeting the Bcr-Abl-FcγRIIb-BTK axis in primary CML CD34+ cells using ibrutinib, in combination with standard TKI therapy, significantly increased apoptosis in quiescent CML stem cells thereby contributing to the eradication of LSCs.. As a potential curative therapeutic approach, we therefore suggest combining Bcr-Abl TKI therapy along with BTK inhibition.


Blood ◽  
2021 ◽  
Author(s):  
Xiaobing Yu ◽  
Leonel Munoz-Sagredo ◽  
Karolin Streule ◽  
Patricia Muschong ◽  
Elisabeth Bayer ◽  
...  

Acute myeloid leukemia (AML) has a poor prognosis under the current standard of care. In recent years, venetoclax, a BCL-2 inhibitor, was approved to treat patients, ineligible for intensive induction chemotherapy. Complete remission rates with venetoclax-based therapies are, however, hampered by minimal residual disease (MRD) in a proportion of patients, leading to relapse. MRD is due to leukemic stem cells retained in bone marrow protective environments; activation of the CXCL12/CXCR4 pathway was shown to be relevant to this process. An important role is also played by cell adhesion molecules such as CD44, which has been shown to be crucial for AML development. Here we show that CD44 is involved in CXCL12 promotion of resistance to venetoclax-induced apoptosis in human AML cell lines and AML patient samples which could be abrogated by CD44 knockdown, knockout or blocking with an anti-CD44 antibody. Split-Venus biomolecular fluorescence complementation showed that CD44 and CXCR4 physically associate at the cell membrane upon CXCL12 induction. In the venetoclax-resistant OCI-AML3 cell line, CXCL12 promoted an increase in the proportion of cells expressing high levels of embryonic-stem-cell core transcription factors (ESC-TFs: Sox2, Oct4, Nanog), abrogated by CD44 knockdown. This ESC-TF-expressing subpopulation which could be selected by venetoclax treatment, exhibited a basally-enhanced resistance to apoptosis, and expressed higher levels of CD44. Finally, we developed a novel AML xenograft model in zebrafish, showing that CD44 knockout sensitizes OCI-AML3 cells to venetoclax treatment in vivo. Our study shows that CD44 is a potential molecular target to sensitize AML cells to venetoclax-based therapies.


Blood ◽  
2020 ◽  
Vol 136 (Supplement 1) ◽  
pp. 41-42
Author(s):  
María Poza ◽  
Rafael Colmenares ◽  
Alba González ◽  
Noemi Alvarez ◽  
Gonzalo Carreño Gomez-Tarragona ◽  
...  

Introduction: Myeloid malignancies are clonal disorders of hematopoietic stem cells and include acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) and myeloproliferative neoplasm (MPN). Common biological markers have been described in the molecular pathogenesis, including gene mutations in splicing factors, epigenetic modifiers, transcription factors, signal pathways and tumor suppressors. These mechanisms have been associated with MDS and MPN progression to AML. Objectives: The main objective of this study is to identify differences in the mutational landscape of myeloid malignancies and describe mutation frequencies of genes and functional pathways in each neoplasm, as well as determine their clinical impact. Methods: This study involved a retrospective analysis of 430 patients with AML (209), MDS (106) and Philadelphia negative MPN (86) diagnosed in the Hospital Universitario 12 de Octubre (Spain). They were analyzed by a next generation sequencing (NGS)- panel for myeloid malignancies. The panel include 32 genes: CALR, ASXL1, EZH2, PHF6, DNMT3A 2, TET2, IDH1, IDH2, KDM6A, KMT2A, SF1, SF3A1, SF3B1, SRSF2, U2AF1, ZRSR2, PRPF40B, EPOR, FLT3, JAK2, KIT, SH2B3, MPL, CBL, HRAS, NRAS, KRAS, ETV6, RUNX1, VHL, TP53, PTEN. In addition, there were included 29 patients diagnosed with benign pathology that were referred to rule out MPN or congenital polyglobulia. Results: In the analyzed cohort we obtained a larger number of mutations in the more aggressive malignancies, AML and MDS. Mutations in epigenetic modifiers and signal pathways were the most frequent detected (31% and 24% respectively). The epigenetic modifiers were notably affected in AML (78%) and MDS (60.4%), whereas signal pathways were mutated more frequently in MPN (70.9%). Transcription factors, tumor suppressors and splicing factors mutations were more detected in AML and MDS (40%, 32%, 44% and 22%, 13%, 32% respectively). The mutation landscape obtained by genes was: Signal pathways: FLT3, NRAS, KIT, KRAS y SH2B3 were specially detected in AML (25%, 11%, 6%, 5% and 4% respectively). JAK2, CALR and MPL in MPN (38%, 15% and 6% respectively). Transcription factors: RUNX1, ETV6, PHF6, CEBPA and WT1 mutations were regularly observed in AML (21%, 6%, 6%, 6% and 5% respectively), and GATA1 in SMD (3.8%). Tumor suppressors: TP53 was particularly affected in AML (21%) and MDS (11%). Epigenetic modifiers: TET2 was notably mutated in MDS (32%), whereas ASXL1, DNMT3A, IDH2, IDH1 and EZH2 were in AML (21%, 21%, 17% 16% and 8% respectively). Splicing factors: SF3B1 was more frequently detected in MDS (18%) than AML (7%), whereas ZRSR2 presented a similar frequency in both pathologies (around 8%). U2AF1 was most commonly mutated in MPN (9%). SRSF2 was specially mutated in AML (23%). SF3A1 was altered in around 1%, similar in all three malignancies. With regard to survival studies, the presence of mutations in splicing factors (primarily in U2AF1) and its absence in signal pathways conferred an adverse outcome for overall survival (OS) in MPN. In MDS, gene mutations in tumor suppressors (especially TP53), U2AF1 splicing factor and EZH2 epigenetic modifier were associated with poor outcome. In our series of AML, gene mutations in tumor suppressors and TP53 were related to unfavorable prognosis in OS. Conclusion: The largest number of mutations and affected genes observed in AML suggest that leukemic transformation of MDS and MPN is conditioned by acquisition of new mutations. We observed different frequencies of mutations between AML, MDS and MPN that could guide the diagnostic and identify new targets of treatment. Further, some mutations have demonstrated differential prognostic impact. An extension of this study and the design of an algorithm with mutation data to elucidate a more accurate molecular prognosis will be presented at the meeting. This work has been financed thanks to the grant PI16/01225, PI 19/01518 and PI19/00730 from the Instituto de Salud Carlos III (Ministerio de Economia, Industria y Competititvidad) and cofinanced by the European Development Fund. Figure 1. Mutations detected (%) in AML, MDS and MPN classified by function. Table 1. Median overall survival of patients with MPN, MDS and AML according to gene state (mutated or not). Figure Disclosures No relevant conflicts of interest to declare.


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