Erythroleukemia: Classification.

Acute erythroid leukemia (AEL) is a rare (2%-5%) form of acute myeloid leukemia (AML). Molecular alterations found in AEL resemble those of other AMLs. We report a classification of AELs in three major classes, with different prognosis and some specific features such as a tendency to mutual exclusion of mutations in epigenetic regulators and signaling genes.

Azacitidine Plus Venetoclax for the Treatment of Relapsed and Newly Diagnosed Acute Myeloid Leukemia Patients.

Venetoclax (VEN) belongs the BH3-mimetic class that selectively targets BCL-2, activating apoptosis. The combination of VEN and azacitidine (AZA) has changed the paradigm of treatment of newly diagnosed (ND) acute myeloid leukemia (AML) patients ineligible for intensive chemotherapy. There is scarce evidence for the use of VEN-AZA for relapsed or refractory (R/R) AML. We compared the outcome of 39 R/R AML and 38 ND AML patients treated between 01/20 and 12/21. The median age was 69 (22-86) and 73 (61-81) in the R/R and ND groups, respectively. Adverse cytogenetics were found in 36% of patients in the R/R group and 59% of patients in the ND group. Overall response rate was 37% in R/R AML, including 13% CR, 8% CRi, 3% PR and 13% MLFS, and 58% in the ND AML, including 32% CR, 13% CRi and 13% MLFS. Adverse cytogenetics was associated with treatment failure in the R/R group (Relative Risk = 0.13, p = 0.005). Median overall survival (OS) was 5.9 months in the R/R group and 9.4 months in the ND group. Median OS was 2.2 months in the adverse cytogenetics group versus 8.7 months in the intermediate cytogenetics group in the R/R group (p = 0.02). Median leukemia-free survival was not different between the two groups (9.4 months and 10.3 months), indicating that VEN-AZA can be an efficient salvage treatment for selected R/R AML patients. In conclusion, VEN-AZA is a promising treatment for ND AML and for selected R/R AML patients.

Human erythroleukemia genetics and transcriptomes identify master transcription factors as functional disease drivers.

Acute erythroleukemia (AEL or acute myeloid leukemia [AML]-M6) is a rare but aggressive hematologic malignancy. Previous studies showed that AEL leukemic cells often carry complex karyotypes and mutations in known AML-associated oncogenes. To better define the underlying molecular mechanisms driving the erythroid phenotype, we studied a series of 33 AEL samples representing 3 genetic AEL subgroups including TP53-mutated, epigenetic regulator-mutated (eg, DNMT3A, TET2, or IDH2), and undefined cases with low mutational burden. We established an erythroid vs myeloid transcriptome-based space in which, independently of the molecular subgroup, the majority of the AEL samples exhibited a unique mapping different from both non-M6 AML and myelodysplastic syndrome samples. Notably, >25% of AEL patients, including in the genetically undefined subgroup, showed aberrant expression of key transcriptional regulators, including SKI, ERG, and ETO2. Ectopic expression of these factors in murine erythroid progenitors blocked in vitro erythroid differentiation and led to immortalization associated with decreased chromatin accessibility at GATA1-binding sites and functional interference with GATA1 activity. In vivo models showed development of lethal erythroid, mixed erythroid/myeloid, or other malignancies depending on the cell population in which AEL-associated alterations were expressed. Collectively, our data indicate that AEL is a molecularly heterogeneous disease with an erythroid identity that results in part from the aberrant activity of key erythroid transcription factors in hematopoietic stem or progenitor cells.

Autoimmune diseases in myelodysplastic syndrome favors patients survival: A case control study and literature review.

BACKGROUND: We conducted a monocentric retrospective study of patients with myelodysplastic syndromes (MDS) and autoimmune or inflammatory disorders (AIMs) and a literature review. We analyzed the association with subgroups of the WHO 2016 MDS classification and patient's survival in a case control study. Risk factors associated with survival were analyzed by uni- and multivariate analysis. RESULTS: From all MDS patients 11% presented with AIMs. These were heterogeneous and the most frequent where polyarthritis (25%) and autoimmune cytopenias (17%). No difference for frequency and type of AIMs was observed for the WHO 2016 MDS subgroups (p = .3). In the case control study WHO classification, karyotype abnormalities, IPSS-R and IPSS were similar in both groups. The overall survival from MDS diagnosis was better in the group with AIMs [10.3 ±â€¯0.6 (IC95% 6.2-12.9) versus 4.8 ±â€¯1.1 years (IC95% 4.2-8.7), p = .04]. The better survival was restricted to MDS with low or intermediate-1 IPSS [11.1 ±â€¯1.5 (IC95% 9.9-NR) versus 8.7 ±â€¯1.3 years (IC95% 4.8-10.3), p = .006]. The better survival was only observed when AIMs diagnosis was timely associated or appeared after MDS diagnosis (p = .04). Factors associated with a better overall survival and survival without AML were steroid dependence [respectively HR = 0.042, p = .003, (IC95% 0.005-0.33) and HR = 0.07, p = .002, (IC95% 0.013-0.39)], a diagnosis of AIMs and MDS timely associated [respectively HR = 0.05, p = .009, (IC95% 0.006-0.478) and HR = 0.1, p = .008, (IC95% 0.018-0.54)] or a diagnosis of AIMs after MDS [respectively HR = 0.024, p = .009, (IC95% 0.001-0.39) and HR = 0.04, p = .008, (IC95% 0.003-0.43)]. CONCLUSION: Autoimmune and inflammatory diseases associated to MDS are heterogeneous. AIMs diagnosed after or concomitantly to MDS seems associated with a better survival. Prospective studies are necessary to demonstrate that autoimmunity is associated to a better control of the MDS clone.

Role of ASXL1 and TP53 mutations in the molecular classification and prognosis of acute myeloid leukemias with myelodysplasia-related changes.

Acute myeloid leukemias (AML) with myelodysplasia-related changes (AML-MRC) are defined by the presence of multilineage dysplasia (MLD), and/or myelodysplastic syndrome (MDS)-related cytogenetics, and/or previous MDS. The goal of this study was to identify distinct biological and prognostic subgroups based on mutations of ASXL1, RUNX1, DNMT3A, NPM1, FLT3 and TP53 in 125 AML-MRC patients according to the presence of MLD, cytogenetics and outcome. ASXL1 mutations (n=26, 21%) were associated with a higher proportion of marrow dysgranulopoiesis (mutant vs. wild-type: 75% vs. 55%, p=0.030) and were mostly found in intermediate cytogenetic AML (23/26) in which they predicted inferior 2-year overall survival (OS, mutant vs. wild-type: 14% vs. 37%, p=0.030). TP53 mutations (n=28, 22%) were mostly found in complex karyotype AML (26/28) and predicted poor outcome within unfavorable cytogenetic risk AML (mutant vs. wild-type: 9% vs. 40%, p=0.040). In multivariate analysis, the presence of either ASXL1 or TP53 mutation was the only independent factor associated with shorter OS (HR, 95%CI: 2.53, 1.40-4.60, p=0.002) while MLD, MDS-related cytogenetics and previous MDS history did not influence OS. We conclude that ASXL1 and TP53 mutations identify two molecular subgroups among AML-MRCs, with specific poor prognosis. This could be useful for future diagnostic and prognostic classifications.

Gene mutations differently impact the prognosis of the myelodysplastic and myeloproliferative classes of chronic myelomonocytic leukemia.

Initially classified in the myelodysplastic syndromes (MDSs), chronic myelomonocytic leukemia (CMML) is currently considered as a MDS/myeloproliferative neoplasm. Two classes-myelodysplastic and myeloproliferative-have been distinguished upon the level of the white blood cell count (threshold 13 G/L). We analyzed mutations in 19 genes reported in CMML to determine if and how these mutations impacted the respective prognosis of the two classes. We defined four major mutated pathways (DNA methylation, ASXL1, splicing, and signaling) and determined their prognostic impact. The number of mutated pathways impacted overall survival in the myelodysplastic class but not in the myeloproliferative class. The myeloproliferative class had a worse prognosis than the myelodysplastic class and was impacted by RUNX1 mutations only. Our results argue for a reclassification of CMML based on the myelodysplastic/myeloproliferative status.

Array comparative genomic hybridization and sequencing of 23 genes in 80 patients with myelofibrosis at chronic or acute phase.

Myelofibrosis is a myeloproliferative neoplasm that occurs de novo (primary myelofibrosis) or results from the progression of polycythemia vera or essential thrombocytemia (hereafter designated as secondary myelofibrosis or post-polycythemia vera/ essential thrombocythemia myelofibrosis). To progress in the understanding of myelofibrosis and to find molecular prognostic markers we studied 104 samples of primary and secondary myelofibrosis at chronic (n=68) and acute phases (n=12) from 80 patients, by using array-comparative genomic hybridization and sequencing of 23 genes (ASXL1, BMI1, CBL, DNMT3A, EZH2, IDH1/2, JAK2, K/NRAS, LNK, MPL, NF1, PPP1R16B, PTPN11, RCOR1, SF3B1, SOCS2, SRSF2, SUZ12, TET2, TP53, TRPS1). We found copy number aberrations in 54% of samples, often involving genes with a known or potential role in leukemogenesis. We show that cases carrying a del(20q), del(17) or del(12p) evolve in acute myeloid leukemia (P=0.03). We found that 88% of the cases were mutated, mainly in signaling pathway (JAK2 69%, NF1 6%) and epigenetic genes (ASXL1 26%, TET2 14%, EZH2 8%). Overall survival was poor in patients with more than one mutation (P=0.001) and in patients with JAK2/ASXL1 mutations (P=0.02). Our study highlights the heterogeneity of myelofibrosis, and points to several interesting copy number aberrations and genes with diagnostic and prognostic impact.

BCOR and BCORL1 mutations in myelodysplastic syndromes and related disorders.

Patients with low-risk myelodysplastic syndromes (MDS) that rapidly progress to acute myeloid leukemia (AML) remain a challenge in disease management. Using whole-exome sequencing of an MDS patient, we identified a somatic mutation in the BCOR gene also mutated in AML. Sequencing of BCOR and related BCORL1 genes in a cohort of 354 MDS patients identified 4.2% and 0.8% of mutations respectively. BCOR mutations were associated with RUNX1 (P = .002) and DNMT3A mutations (P = .015). BCOR is also mutated in chronic myelomonocytic leukemia patients (7.4%) and BCORL1 in AML patients with myelodysplasia-related changes (9.1%). Using deep sequencing, we show that BCOR mutations arise after mutations affecting genes involved in splicing machinery or epigenetic regulation. In univariate analysis, BCOR mutations were associated with poor prognosis in MDS (overall survival [OS]: P = .013; cumulative incidence of AML transformation: P = .005). Multivariate analysis including age, International Prognostic Scoring System, transfusion dependency, and mutational status confirmed a significant inferior OS to patients with a BCOR mutation (hazard ratio, 3.3; 95% confidence interval, 1.4-8.1; P = .008). These data suggest that BCOR mutations define the clinical course rather than disease initiation. Despite infrequent mutations, BCOR analyses should be considered in risk stratification.

Prognostic score including gene mutations in chronic myelomonocytic leukemia.

PURPOSE: Several prognostic scoring systems have been proposed for chronic myelomonocytic leukemia (CMML), a disease in which some gene mutations-including ASXL1-have been associated with poor prognosis in univariable analyses. We developed and validated a prognostic score for overall survival (OS) based on mutational status and standard clinical variables. PATIENTS AND METHODS: We genotyped ASXL1 and up to 18 other genes including epigenetic (TET2, EZH2, IDH1, IDH2, DNMT3A), splicing (SF3B1, SRSF2, ZRSF2, U2AF1), transcription (RUNX1, NPM1, TP53), and signaling (NRAS, KRAS, CBL, JAK2, FLT3) regulators in 312 patients with CMML. Genotypes and clinical variables were included in a multivariable Cox model of OS validated by bootstrapping. A scoring system was developed using regression coefficients from this model. RESULTS: ASXL1 mutations (P < .0001) and, to a lesser extent, SRSF2 (P = .03), CBL (P = .003), and IDH2 (P = .03) mutations predicted inferior OS in univariable analysis. The retained independent prognostic factors included ASXL1 mutations, age older than 65 years, WBC count greater than 15 ×10(9)/L, platelet count less than 100 ×10(9)/L, and anemia (hemoglobin < 10 g/dL in female patients, < 11g/dL in male patients). The resulting five-parameter prognostic score delineated three groups of patients with median OS not reached, 38.5 months, and 14.4 months, respectively (P < .0001), and was validated in an independent cohort of 165 patients (P < .0001). CONCLUSION: A new prognostic score including ASXL1 status, age, hemoglobin, WBC, and platelet counts defines three groups of CMML patients with distinct outcomes. Based on concordance analysis, this score appears more discriminative than those based solely on clinical parameters.

Molecular similarity between myelodysplastic form of chronic myelomonocytic leukemia and refractory anemia with ring sideroblasts.

Chronic myelomonocytic leukemia is similar to but a separate entity from both myeloproliferative neoplasms and myelodysplastic syndromes, and shows either myeloproliferative or myelodysplastic features. We ask whether this distinction may have a molecular basis. We established the gene expression profiles of 39 samples of chronic myelomonocytic leukemia (including 12 CD34-positive) and 32 CD34-positive samples of myelodysplastic syndromes by using Affymetrix microarrays, and studied the status of 18 genes by Sanger sequencing and array-comparative genomic hybridization in 53 samples. Analysis of 12 mRNAS from chronic myelomonocytic leukemia established a gene expression signature of 122 probe sets differentially expressed between proliferative and dysplastic cases of chronic myelomonocytic leukemia. As compared to proliferative cases, dysplastic cases over-expressed genes involved in red blood cell biology. When applied to 32 myelodysplastic syndromes, this gene expression signature was able to discriminate refractory anemias with ring sideroblasts from refractory anemias with excess of blasts. By comparing mRNAS from these two forms of myelodysplastic syndromes we derived a second gene expression signature. This signature separated the myelodysplastic and myeloproliferative forms of chronic myelomonocytic leukemias. These results were validated using two independent gene expression data sets. We found that myelodysplastic chronic myelomonocytic leukemias are characterized by mutations in transcription/epigenetic regulators (ASXL1, RUNX1, TET2) and splicing genes (SRSF2) and the absence of mutations in signaling genes. Myelodysplastic chronic myelomonocytic leukemias and refractory anemias with ring sideroblasts share a common expression program suggesting they are part of a continuum, which is not totally explained by their similar but not, however, identical mutation spectrum.

Myeloid malignancies: mutations, models and management.

Myeloid malignant diseases comprise chronic (including myelodysplastic syndromes, myeloproliferative neoplasms and chronic myelomonocytic leukemia) and acute (acute myeloid leukemia) stages. They are clonal diseases arising in hematopoietic stem or progenitor cells. Mutations responsible for these diseases occur in several genes whose encoded proteins belong principally to five classes: signaling pathways proteins (e.g. CBL, FLT3, JAK2, RAS), transcription factors (e.g. CEBPA, ETV6, RUNX1), epigenetic regulators (e.g. ASXL1, DNMT3A, EZH2, IDH1, IDH2, SUZ12, TET2, UTX), tumor suppressors (e.g. TP53), and components of the spliceosome (e.g. SF3B1, SRSF2). Large-scale sequencing efforts will soon lead to the establishment of a comprehensive repertoire of these mutations, allowing for a better definition and classification of myeloid malignancies, the identification of new prognostic markers and therapeutic targets, and the development of novel therapies. Given the importance of epigenetic deregulation in myeloid diseases, the use of drugs targeting epigenetic regulators appears as a most promising therapeutic approach.

Mutation analysis of ASXL1, CBL, DNMT3A, IDH1, IDH2, JAK2, MPL, NF1, SF3B1, SUZ12, and TET2 in myeloproliferative neoplasms.

Since the discovery of the JAK2V617F tyrosine kinase-activating mutation several genes have been found mutated in nonchronic myeloid leukemia (CML) myeloproliferative neoplasms (MPNs), which mainly comprise three subtypes of "classic" MPNs; polycythemia vera (PV), essential thrombocythemia (ET), and myelofibrosis (MF). We searched for mutations in ASXL1, CBL, DNMT3A, IDH1, IDH2, JAK2, MPL, NF1, SF3B1, SUZ12, and TET2 genes in 149 non-CML MPNs, including 127 "classic" MPNs cases. JAK2 was mutated in 100% PV, 66% ET and 68% MF. We found a high incidence of ASXL1 mutation in MF patients (20%) and a low incidence in PV (7%) and ET (4%) patients. Mutations in the other genes were rare (CBL, DNMT3A, IDH2, MPL, SF3B1, SUZ12, NF1) or absent (IDH1).