[GATA2 gene mutations: 3 cases]. / Mutations du gène GATA2 : à propos de 3 cas.

INTRODUCTION: Heterozygous germline mutations of GATA2 gene (guanine-adenine-thymine-adenine binding protein 2) are hereditary mutations that can be pathogenic, sometimes occurring sporadically, responsible for a florid clinical-biological picture, sometimes serious and quickly leading to the death. CASE REPORTS: We reported two women and one man with germline mutations in the GATA2 gene. The first patient, aged 19, initially presented with monocytopenia and chronic lymphedema of the four limbs, suggestive of Emberger syndrome. The second patient, 28-years-old, presented with a disseminated atypical mycobacterium (Mycobacterium kansasii) infection, raising suspicion of an immune deficiency such as MonoMAC syndrome (deficiency syndrome of dendritic cells, monocytes, B lymphocytes and NK cells). The last patient, 30-years-old, presented with pancytopenia, leading to the diagnosis of a family form of myelodysplastic syndromes and acute myeloid leukemia characterized by a mutation of the GATA2 gene. CONCLUSIONS: Each case illustrates a typical clinical presentation of GATA2 deficiency, although the evolution of these syndromes ultimately reveals a complex, heterogeneous and intricate picture of hematological, dermatological, infectious, pulmonary, ENT or oncological symptoms. Mutations in the GATA2 gene remain a diagnostic and therapeutic challenge for the internist, and require multidisciplinary management given the florid picture that can be of interest to all specialties. The clinical spectrum of these GATA2 mutations as well as the latest management recommendations from the recent litterature and the "GATA2 club" are described in this article.

Effects of azacitidine in 93 patients with IDH1/2 mutated acute myeloid leukemia/myelodysplastic syndromes: a French retrospective multicenter study.

Isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) mutations in Myeloid Neoplams (MNs) exhibit DNA hypermethylation via 2-hydroxyglutarate (2HG) over-production. Clinical impact of azacitidine (AZA) remains inconsistent in IDH1/2-mutated MNs and the potential of serum 2HG as a suitable marker of response to AZA is unknown. To address these questions, we retrospectively analyzed 93 MNs patients (78 AML, 11 MDS, 4 CMML) with IDH1/2 mutations treated with AZA. After a median of 5 cycles of AZA, overall response rate was 28% (including 15% complete remission) and median OS was 12.3 months (significantly shorter in AML compared to MDS/CMML patients). In multivariate analysis of AML patients, DNMT3A mutation was associated with shorter OS while IDH1/2 mutation subtypes had no independent impact. No difference was observed in serum 2HG levels upon AZA treatment between responding and refractory patients suggesting that serum 2HG cannot be used as a surrogate marker of AZA response.

Outcomes and mutational analysis of patients with lower-risk non-del5q myelodysplastic syndrome treated with antithymocyte globulin with or without ciclosporine A.

Immunosuppressive treatment is a disease-modifying therapy for lower-risk myelodysplastic syndromes (MDS). However, IST is relatively rarely used and long-term outcomes of patients are seldom reported. We retrospectively studied outcomes of 20 patients with lower-risk non del 5q MDS with transfusion dependency, with horse or rabbit antithymocyte globulin ±â€¯ciclosporine A, and frontline eltrombopag in two of them. IPSS-R was low, intermediate and high in 30%, 55% and 10% of the patients, respectively. Fifty-five percent of the patients had hypocellular bone marrow (BM). Baseline mutations were detected in 31.5% of the patients and were more frequent in patients with normo/hypercellular MDS than in patients with hypocellular MDS. Transfusion independence rate for both red blood cells (RBC) and platelets was achieved in 45% of patients. RBC transfusion duration ≤6 months, B-cell counts >0.2 G/L and, marginally, BM blasts ≤2% were associated with higher transfusion independence rate. Age and cellularity did not influence the response rate. Median transfusion independence duration was 53 months. Cumulative incidence of progression to a more aggressive myeloid disease was 0 in patients without baseline mutations and 33% in patients with baseline mutations (P = .008). Median progression-free and overall survival after treatment onset and median overall survival after loss of transfusion independence were 45.5 months, 68 months and not reached, respectively. In conclusion, antithymocyte globulin ±â€¯ciclosporine A results in durable responses in MDS, irrespective of age, in patients with lower-risk disease without B-cell lymphopenia and treated early in the course of the disease.

Impact of Wilms' tumor 1 expression on outcome of patients undergoing allogeneic stem cell transplantation for AML.

The monitoring of the minimal residual disease by Wilms' tumor 1 expression (MRDWT1) is a standardized test, which can be used in over 80% of patients with AML. To investigate the prognostic value of MRDWT1 in patients undergoing allogeneic stem cell transplantation (allo-SCT) for AML, MRDWT1 was monitored 3 months after transplantation in 139 patients. MRDWT1 positivity did not lead to any therapeutic intervention. Median follow-up was 39.3 (6.4-99.8) months. Patients with positive MRDWT1 at 3 months experienced more often post-transplant relapse (27/30, 90%) than those with negative MRDWT1 (16/109, 14.7%) (P<0.0001). Similarly, a shorter 3-year event-free survival (EFS) was observed in MRDWT1-positive patients (10% vs 72.3% in MRDWT1-negative patients, P<0.0001). The correlation between relapse and MRDWT1 was stronger in blood than in bone marrow samples. Multivariate analysis confirmed the detrimental role of 3-month positive MRDWT1 for relapse (hazard ratio (HR): 15.42; 95% confidence interval (CI): 7.53-31.59; P<0.0001) and EFS (HR: 10.71; 95% CI: 5.41-21.21; P<0.0001). Interestingly, 3-month chimerism was less predictive of relapse than positive MRDWT1. In conclusion, our results demonstrate the usefulness of peripheral blood MRDWT1 monitoring in identifying very high-risk patients, who could benefit from an early preemptive treatment, and those who do not need such an intervention.

Copy-number analysis identified new prognostic marker in acute myeloid leukemia.

Recent advances in genomic technologies have revolutionized acute myeloid leukemia (AML) understanding by identifying potential novel actionable genomic alterations. Consequently, current risk stratification at diagnosis not only relies on cytogenetics, but also on the inclusion of several of these abnormalities. Despite this progress, AML remains a heterogeneous and complex malignancy with variable response to current therapy. Although copy-number alterations (CNAs) are accepted prognostic markers in cancers, large-scale genomic studies aiming at identifying specific prognostic CNA-based markers in AML are still lacking. Using 367 AML, we identified four recurrent CNA on chromosomes 11 and 21 that predicted outcome even after adjusting for standard prognostic risk factors and potentially delineated two new subclasses of AML with poor prognosis. ERG amplification, the most frequent CNA, was related to cytarabine resistance, a cornerstone drug of AML therapy. These findings were further validated in The Cancer Genome Atlas data. Our results demonstrate that specific CNA are of independent prognostic relevance, and provide new molecular information into the genomic basis of AML and cytarabine response. Finally, these CNA identified two potential novel risk groups of AML, which when confirmed prospectively, may improve the clinical risk stratification and potentially the AML outcome.

Lenalidomide with or without erythropoietin in transfusion-dependent erythropoiesis-stimulating agent-refractory lower-risk MDS without 5q deletion.

After failure of erythropoiesis-stimulating agents (ESAs), lenalidomide (LEN) yields red blood cell (RBC) transfusion independence (TI) in 20-30% of lower-risk non-del5q myelodysplastic syndrome (MDS). Several observations suggest an additive effect of ESA and LEN in this situation. We performed a randomized phase III study in 131 RBC transfusion-dependent (TD, median transfusion requirement six RBC units per 8 weeks) lower-risk ESA-refractory non-del5q MDS. Patients received LEN alone, 10 mg per day, 21 days per 4 weeks (L arm) or LEN (same schedule) + erythropoietin (EPO) beta, 60,000 U per week (LE arm). In an intent-to-treat (ITT) analysis, erythroid response (HI-E, IWG 2006 criteria) after four treatment cycles (primary end point) was 23.1% (95% CI 13.5-35.2) in the L arm and 39.4% (95% CI 27.6-52.2) in the LE arm (P=0.044), while RBC-TI was reached in 13.8 and 24.2% of the patients in the L and LE arms, respectively (P=0.13). Median response duration was 18.1 and 15.1 months in the L and LE arms, respectively (P=0.47). Side effects were moderate and similar in the two arms. Low baseline serum EPO level and a G polymorphism of CRBN gene predicted HI-E. Combining LEN and EPO significantly improves erythroid response over LEN alone in lower-risk non-del5q MDS patients with anemia resistant to ESA.

Interferon decreases VEGF levels in patients with chronic myeloid leukemia treated with imatinib.

In chronic myeloid leukemia (CML), evidence is supporting the role of VEGF in growth, and survival of leukemia cells. The evaluation of plasma VEGF levels in 403 CML patients randomized within SPIRIT study to received imatinib-400mg versus imatinib+cytarabine versus imatinib+interferon (IFN) versus imatinib-600mg demonstrated that VEGF is an independent factor of BCR-ABL burden. VEGF low levels at diagnosis were associated with a progression-free survival of 100% at 48 months. Under treatment, significant lowest levels were observed in imatinib+IFN arm. These results support the use of VEGF as a parameter to predict CML evolution and let us to speculate about antiangiogenic properties of IFN.

Evaluation of allogeneic hematopoietic SCT in younger adults with adverse karyotype AML.

To illustrate methodological issues, we compared donor vs no-donor to transplant vs no-transplant comparisons in a cohort of 107 patients aged 50 years with adverse karyotype AML in first CR. Adverse karyotypes were defined as -7, del(7q), -5, del(5q), t(9;22), 11q23, 3q26 or complex abnormalities. Mantel-Byar estimations and hematopoietic SCT (HSCT) as a time-dependent variable were used to compare transplant vs no-transplant cumulative incidence of relapse (CIR), relapse-free survival (RFS) and OS. In all, 52 patients had a sibling donor, but only 35 of them were transplanted in first CR, whereas 9 patients received HSCT from alternative stem cell sources. Donor-based analysis showed lower CIR in the donor group, not translating in prolonged RFS or OS. Conversely, transplant-based analysis showed that HSCT in the first CR improved the three CIR (multivariate hazard ratio (HR), 0.31; P<0.001), RFS (multivariate HR, 0.57; P=0.047) and OS (multivariate HR, 0.54; P=0.03) endpoints. At 5 years, OS was estimated at 33% in transplanted vs 18% in non-transplanted patients. The positive effect of HSCT was more pronounced in patients aged 35 years and/or in those transplanted in the more recent years. These results confirm that HSCT is likely the best curative option in younger patients with adverse karyotype AML.

Prognostic significance of DNA methyltransferase 3A mutations in cytogenetically normal acute myeloid leukemia: a study by the Acute Leukemia French Association.

Recently, DNA methyltransferase 3A (DNMT3A) mutations have been identified in acute myeloid leukemia (AML), the highest frequency being found within cytogenetically normal (CN) AML. In this study, diagnostic samples from 123 adults younger than 60 years with primary CN-AML homogeneously treated in the Acute Leukemia French Association-9801 and -9802 trials were screened for mutations in DNMT3A-conserved domains by direct sequencing. Patients were also assessed for the presence of FLT3 (fms-like tyrosine kinase receptor-3), NPM1 (nucleophosmin), CEBPA, WT1 (Wilms tumor 1), IDH1 (isocitrate dehydrogenase 1) and IDH2 mutations. Thirty-eight mutations were detected in 36 patients (29%): 36 nucleotide substitutions, mostly affecting amino-acid residue R882 and two frameshift deletions. DNMT3A mutations were significantly associated with the French-American-British subtypes M4/M5 and the presence of NPM1 mutations. In the whole cohort, DNMT3A mutated patients had a shorter event-free survival (5-year EFS: 13% vs 32%, P = 0.02) and overall survival (5-year OS: 23% vs 45%, P = 0.02) compared with DNMT3A wild-type patients. In multivariate analysis including age, white blood cell count, NPM1/FLT3-internal tandem duplication/CEBPA risk group and DNMT3A mutational status, the presence of a DNMT3A mutation remained an independent adverse prognostic factor for EFS and OS, suggesting that testing for DNMT3A mutations could help further improve risk stratification in CN-AML.

GILZ inhibits the mTORC2/AKT pathway in BCR-ABL(+) cells.

The malignant phenotype of chronic myeloid leukemia (CML) is due to the abnormal tyrosine kinase activity of the BCR-ABL oncoprotein, which signals several downstream cell survival pathways, including phosphoinositide 3-kinase/AKT, signal transducer and activator of transcription 5 and extracellular signal-regulated kinase 1/2. In patients with CML, tyrosine kinase inhibitors (TKIs) are used to suppress the BCR-ABL tyrosine kinase, resulting in impressive response rates. However, resistance can occur, especially in acute-phase CML, through various mechanisms. Here, we show that the glucocorticoid-induced leucine zipper protein (GILZ) modulates imatinib and dasatinib resistance and suppresses tumor growth by inactivating the mammalian target of rapamycin complex-2 (mTORC2)/AKT signaling pathway. In mouse and human models, GILZ binds to mTORC2, but not to mTORC1, inhibiting phosphorylation of AKT (at Ser473) and activating FoxO3a-mediated transcription of the pro-apoptotic protein Bim; these results demonstrate that GILZ is a key inhibitor of the mTORC2 pathway. Furthermore, CD34(+) stem cells isolated from relapsing CML patients underwent apoptosis and showed inhibition of mTORC2 after incubation with glucocorticoids and imatinib. Our findings provide new mechanistic insights into the role of mTORC2 in BCR-ABL(+) cells and indicate that regulation by GILZ may influence TKI sensitivity.

Impact of TET2 mutations on response rate to azacitidine in myelodysplastic syndromes and low blast count acute myeloid leukemias.

The impact of ten-eleven-translocation 2 (TET2) mutations on response to azacitidine (AZA) in MDS has not been reported. We sequenced the TET2 gene in 86 MDS and acute myeloid leukemia (AML) with 20-30% blasts treated by AZA, that is disease categories wherein this drug is approved by Food and Drug Administration (FDA). Thirteen patients (15%) carried TET2 mutations. Patients with mutated and wild-type (WT) TET2 had mostly comparable pretreatment characteristics, except for lower hemoglobin, better cytogenetic risk and longer MDS duration before AZA in TET2 mutated patients (P=0.03, P=0.047 and P=0.048, respectively). The response rate (including hematological improvement) was 82% in MUT versus 45% in WT patients (P=0.007). Mutated TET2 (P=0.04) and favorable cytogenetic risk (intermediate risk: P=0.04, poor risk: P=0.048 compared with good risk) independently predicted a higher response rate. Response duration and overall survival were, however, comparable in the MUT and WT groups. In higher risk MDS and AML with low blast count, TET2 status may be a genetic predictor of response to AZA, independently of karyotype.

NOTCH1 and FBXW7 mutations have a favorable impact on early response to treatment, but not on outcome, in children with T-cell acute lymphoblastic leukemia (T-ALL) treated on EORTC trials 58881 and 58951.

Risk-adjusted treatment stratification in T-cell acute lymphoblastic leukemias (T-ALLs) is currently based only on early response to chemotherapy. We investigated the prognostic implication of hyperactivation of NOTCH pathway resulting from mutations of NOTCH1 or FBXW7 in children with T-ALL enrolled in EORTC-CLG trials. Overall, 80 out of 134 (60%) patients were NOTCH+ (NOTCH1 and/or FBXW7 mutated). Although clinical presentations were not significantly associated with NOTCH status, NOTCH+ patients showed a better early response to chemotherapy as compared with NOTCH- patients, according to the rate of poor pre-phase 'responders' (25% versus 44%; P=0.02) and the incidence of high minimal residual disease (MRD) levels (11% (7/62) versus 32% (10/31); P=0.01) at completion of induction. However, the outcome of NOTCH+ patients was similar to that of NOTCH- patients, with a 5-year event-free survival (EFS) of 73% and 70% (P=0.82), and 5-year overall survival of 82% and 79% (P=0.62), respectively. In patients with high MRD levels, the 5-year EFS rate was 0% (NOTCH+) versus 42% (NOTCH-), whereas in those with low MRD levels, the outcome was similar: 76% (NOTCH+) versus 78% (NOTCH-). The incidence of isolated central nervous system (CNS) relapses was relatively high in NOTCH1+ patients (8.3%), which could be related to a higher propensity of NOTCH+ leukemic blasts to target the CNS.