Protein arginine methyltransferase 2 controls inflammatory signaling in acute myeloid leukemia.

Arginine methylation is catalyzed by protein arginine methyltransferases (PRMTs) and is involved in various cellular processes, including cancer development. PRMT2 expression is increased in several cancer types although its role in acute myeloid leukemia (AML) remains unknown. Here, we investigate the role of PRMT2 in a cohort of patients with AML, PRMT2 knockout AML cell lines as well as a Prmt2 knockout mouse model. In patients, low PRMT2 expressors are enriched for inflammatory signatures, including the NF-κB pathway, and show inferior survival. In keeping with a role for PRMT2 in control of inflammatory signaling, bone marrow-derived macrophages from Prmt2 KO mice display increased pro-inflammatory cytokine signaling upon LPS treatment. In PRMT2-depleted AML cell lines, aberrant inflammatory signaling has been linked to overproduction of IL6, resulting from a deregulation of the NF-κB signaling pathway, therefore leading to hyperactivation of STAT3. Together, these findings identify PRMT2 as a key regulator of inflammation in AML.

Prognostic value of postinduction medullary myeloid recovery by flow cytometry in acute myeloid leukemia.

Risk stratification and treatment response evaluation are key features in acute myeloid leukemia (AML) management. Immunophenotypic and molecular approaches all rely on the detection of persisting leukemic cells by measurable residual disease techniques. A new approach is proposed here by assessing medullary myeloid maturation by flow cytometry through a myeloid progenitor ratio (MPR). The normal MPR range was defined using reference normal bone marrows (n = 48). MPR was considered balanced if between 1 and 4 and unbalanced if < 1 or > 4. MPR was retrospectively assessed at baseline and post-induction for 206 newly diagnosed AML patients eligible for intensive treatment from two different French centers. All AML baseline MPR were unbalanced and thus significantly different from normal MPR (p < 0.0001). Patients with an unbalanced MPR after induction had worse 3-year overall survival (OS) (44.4% vs. 80.2%, HR, 2.96; 95% CI, 1.81-4.84, p < 0.0001) and 3-year relapse free survival (RFS) (38.7% vs. 64.4%, HR, 2.11; 95% CI, 1.39-3.18, p < 0.001). In multivariate analysis, postinduction unbalanced MPR was significantly associated with shorter OS and RFS regardless of the European LeukemiaNet 2010 risk stratification or NPM1/FLT3-ITD status. A balanced postinduction MPR conversely conferred favorable outcomes and reflects medullary myeloid recovery.

Glycemic control in people with diabetes treated with cancer chemotherapy: contribution of continuous glucose monitoring.

AIMS: The aim of our study was to assess, with Continuous Glucose Monitoring (CGM), exhaustive information on the glucose profile in people with diabetes starting chemotherapy. We also evaluated the adaptation of glucose-lowering drugs following analysis of CGM recordings. METHODS: Eighty-five people with diabetes starting chemotherapy were included in the ONCODIAB study. A CGM was worn for up to fourteen days in blinded mode before and after the diabetologist's intervention to evaluate the impact of modifying the glucose-lowering drugs. RESULTS: Time spent in range was 67.2 ± 24.2%. Time below the target glucose range (TBR) (< 70 mg/dl) was 8.9% in all the study population. TBR was significantly higher in patients treated with at least one drug due to the risk of hypoglycemia compared to the others (11.5% vs. 4.4%, p = 0.009). Sixty-five patients had available sensor data for the two recordings. Forty-one patients (51.9%) saw a decrease in their antidiabetic treatment after the diabetologist's intervention guided by the first CGM recording. We observed a significant reduction in the time spent below the target glucose range (70-55 mg/dl) between the two CGM recordings (10.3 ± 14.6% vs. 6.3 ± 9.4%, p = 0.016 and 3.8 ± 8.4% vs. 1.2 ± 2.9%, p = 0.012, respectively). CONCLUSIONS: CGM use in blinded mode could be an interesting tool to reduce the risk of hypoglycemia in people with diabetes starting chemotherapy. Our findings fully support the recommendation that assessing hypoglycemia risk should be mandatory in patients with diabetes before starting chemotherapy.

Protein Arginine Methyltransferases as Therapeutic Targets in Hematological Malignancies.

Arginine methylation is a common post-translational modification affecting protein activity and the transcription of target genes when methylation occurs on histone tails. There are nine protein arginine methyltransferases (PRMTs) in mammals, divided into subgroups depending on the methylation they form on a molecule of arginine. During the formation and maturation of the different types of blood cells, PRMTs play a central role by controlling cell differentiation at the transcriptional level. PRMT enzymatic activity is necessary for many cellular processes in hematological malignancies, such as the activation of cell cycle and proliferation, inhibition of apoptosis, DNA repair processes, RNA splicing, and transcription by methylating histone tails' arginine. Chemical tools have been developed to inhibit the activity of PRMTs and have been tested in several models of hematological malignancies, including primary samples from patients, xenografts into immunodeficient mice, mouse models, and human cell lines. They show a significant effect by reducing cell viability and increasing the overall survival of mice. PRMT5 inhibitors have a strong therapeutic potential, as phase I clinical trials in hematological malignancies that use these molecules show promising results, thus, underlining PRMT inhibitors as useful therapeutic tools for cancer treatment in the future.

Clinical and Economic Impact of a Multidisciplinary Follow-Up Program in Lymphoma Patients.

Objectives: The UMACOACH Lymphoma is a multidisciplinary monitoring program for patients initiating a first highly haematotoxic treatment for Hodgkin or non-Hodgkin lymphoma. Patient follow-up is based on consultation with a pharmacist and planed phone calls by nurses supervised by a clinical haematologist. Our objective was to assess effectiveness and cost of the UMACOACH Lymphoma Program (ULP) and to investigate patient satisfaction and quality of life (QoL). Methods: This French monocentric case-control study included all patients enrolled in the ULP over a one-year period (cases) matched with retrospective patients receiving usual care (controls). Numbers of adverse events (AEs), re-hospitalisations, average relative dose intensity (ARDI), treatment response and survival were compared between the two groups. Among cases, patient satisfaction and QoL using the EORTC-QLQC30 questionnaire before and after treatment were evaluated. Results: Seventy-eight cases were matched to 78 controls. Twenty-six percent grade 3−4 AEs were observed in cases versus 38% in controls (p = 0.001). There were 76 and 88 re-hospitalisations in the case and control groups, respectively (p = 0.217). ARDI > 85% was observed in 92% and 82% of cases and controls, respectively (p = 0.138). No differences were observed in terms of treatment responses and survival. Estimated cost savings were of EUR 81,782 in favour of the case group. An improvement of 5.1 points was observed in the total QoL score before and after treatment in cases. Conclusions: A nurse−pharmacist−haematologist collaboration seems to be promising to reduce grade 3−4 AEs in HL and NHL patients receiving highly haematotoxic chemotherapy regimens. Cost savings from hospitalisation being avoided were also shown.

Influence of Sociodemographic Determinants on the Hodgkin Lymphoma Baseline Characteristics in Long Survivors Patients Enrolled in the Prospective Phase 3 Trial AHL2011.

INTRODUCTION: Whereas numerous studies on several cancers describe the link between social conditions and disease severity, little is known about the social and demographic characteristics of Hodgkin lymphoma (HL) patients. At diagnosis, 10-15% of the patients in the advanced stages have a well-known poor outcome owing to their chemoresistance, but the determinants of the more advanced stages remain elusive. The objective of the present study was to decipher the potential impact of social disparities on the disease features at diagnosis and analyze how the sociodemographic patient features could impact the HL outcome of patients with advanced-stage HL enrolled in the AHL2011 trial. METHODS: This ancillary study was conducted on a cohort of patients from French centers that had recruited more than five patients in the phase III AHL2011 study (NCT0135874). Patients had to be alive at the time of the ancillary study and had to have given their consent to answer the questionnaire. Pre-treatment data (age, gender, stage, B symptoms, IPS), the treatment received, the responses to PET-CT, and the presence of serious adverse events (serious adverse events-SAEs) were all extracted from the AHL2011 trial database. Sociodemographic data-marital status, living area, level of education, socio-professional category, and professional situation-were extracted from the questionnaires. The population density at the point of diagnosis was determined based on ZIP Code, and the distance from the reference medical center was then calculated by the road network. Baseline PET acquisition was performed before any treatment. PET images at baseline were centrally reviewed. The total metabolic tumor volume (TMTV) at the baseline was calculated using a 41% SUVmax cutoff for each lesion. Progression-free survival was defined as the time from randomization to the first progression, relapse, or death from any cause or the last follow-up. The data cutoff for the analyses presented here was 31 October 2017. The progression-free survival was analyzed on an intention-to-treat basis. RESULTS: Among the 823 patients enrolled in the AHL2011 study, the questionnaire was sent to 394 patients, of whom 232 (58.9%) responded. At the time of HL diagnosis, 61.9% (N = 143) of patients declared that they were not socially isolated, 38.1% (N = 88) that they were single, 163 (71.2%) had a professional activity, and 66 (28.8%) were inactive owing to unemployment, retirement, or sick leave. Of the patients, 31.1% (N = 71) lived in a rural region, compared to 68.9% (N = 157) that lived in an urban region. The residence ZIP Code at the time of HL diagnosis was available for 163 (70%). Sociodemographic characteristics did not influence the presence of usual prognostic factors (ECOG, B symptoms, bulky mass, IPS) except for professional activity, which was associated with more frequent low IPS (0-2) (79 (48.5%) active versus 20 (30.3%) inactive patients; p = 0.012). Likewise, no correlation was observed between TMTV and sociodemographic characteristics. However, the TMTV quartile distribution was different according to the living area, with the two upper quartiles being enriched with patients living in a rural area (p = 0.008). Moreover, a negative correlation between the average number of the living area's inhabitants and TMTV (R Pearson = -0.29, p = 0.0004) was observed. CONCLUSION: This study focused on sociodemographic parameters in advanced-stage HL patients and shows that professional activity is associated with more favorable disease features (low IPS), while patients living in rural or low-populated areas are more likely to have an unfavorable HL presentation with a high tumor burden (high TMTV). These data suggest that some patient sociodemographic characteristics might impact either access to medical care or environmental exposure, leading to a higher frequency of unfavorable presentations. Further prospective sociodemographic studies are necessary to confirm these preliminary results.

Identification of novel, clonally stable, somatic mutations targeting transcription factors PAX5 and NKX2-3, the epigenetic regulator LRIF1, and BRAF in a case of atypical B-cell chronic lymphocytic leukemia harboring a t(14;18)(q32;q21).

Diagnosis of B-cell chronic lymphocytic leukemia (B-CLL) is usually straightforward, involving clinical, immunophenotypic (Matutes score), and (immuno)genetic analyses (to refine patient prognosis for treatment). CLL cases with atypical presentation (e.g., Matutes ≤ 3) are also encountered, and for these diseases, biology and prognostic impact are less clear. Here we report the genomic characterization of a case of atypical B-CLL in a 70-yr-old male patient; B-CLL cells showed a Matutes score of 3, chromosomal translocation t(14;18)(q32;q21) (BCL2/IGH), mutated IGHV, deletion 17p, and mutations in BCL2, NOTCH1 (subclonal), and TP53 (subclonal). Quite strikingly, a novel PAX5 mutation that was predicted to be loss of function was also seen. Exome sequencing identified, in addition, a potentially actionable BRAF mutation, together with novel somatic mutations affecting the homeobox transcription factor NKX2-3, known to control B-lymphocyte development and homing, and the epigenetic regulator LRIF1, which is implicated in chromatin compaction and gene silencing. Neither NKX2-3 nor LRIF1 mutations, predicted to be loss of function, have previously been reported in B-CLL. Sequencing confirmed the presence of these mutations together with BCL2, NOTCH1, and BRAF mutations, with the t(14;18)(q32;q21) translocation, in the initial diagnostic sample obtained 12 yr prior. This is suggestive of a role for these novel mutations in B-CLL initiation and stable clonal evolution, including upon treatment withdrawal. This case extends the spectrum of atypical B-CLL with t(14;18)(q32;q21) and highlights the value of more global precision genomics for patient follow-up and treatment in these patients.

T-cell acute lymphoblastic leukemia displays autocrine production of Interleukin-7.

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy characterized by an accumulation of immature T cells. Although patient outcomes have improved, novel targeted therapies are needed to reduce the intensity of chemotherapy and improve the prognosis of high-risk patients. Interleukin-7 (IL-7) modulates the survival and proliferation of normal and malignant T cells. Targeting the IL-7 signaling pathway is thus a potentially effective therapeutic strategy. To achieve such aim, it is essential to first understand how the IL-7 signaling pathway is activated. Although IL-7 production has been observed from multiple stromal tissues, T-ALL autocrine IL-7 secretion has not yet been described. Interestingly, using T-ALL cell lines, primary and patient-derived xenotransplanted (PDX) T-ALL cells, we demonstrate that T-ALL cells produce IL-7 whereas normal T cells do not. Finally, using knock down of IL7 gene in T-ALL cells, we describe to what extent IL-7 autocrine secretion is involved in the T-ALL cells propagation in bone marrow and how it affects the number of leukemia-initiating cells in PDX mice. Together, these results demonstrate how the autocrine production of the IL-7 cytokine mediated by T-ALL cells can be involved in the oncogenic development of T-ALL and offer novel insights into T-ALL spreading.

Serpin B1 defect and increased apoptosis of neutrophils in Cohen syndrome neutropenia.

Cohen syndrome (CS) is a rare genetic disorder due to mutations in VPS13B gene. Among various clinical and biological features, CS patients suffer from inconsistent neutropenia, which is associated with recurrent but minor infections. We demonstrate here that this neutropenia results from an exaggerate rate of neutrophil apoptosis. Besides this increased cell death, which occurs in the absence of any endoplasmic reticulum stress or defect in neutrophil elastase (ELANE) expression or localization, all neutrophil functions appeared to be normal. We showed a disorganization of the Golgi apparatus in CS neutrophils precursors, that correlates with an altered glycosylation of ICAM-1 in these cells, as evidenced by a migration shift of the protein. Furthermore, a striking decrease in the expression of SERPINB1 gene, which encodes a critical component of neutrophil survival, was detected in CS neutrophils. These abnormalities may account for the excessive apoptosis of neutrophils leading to neutropenia in CS. KEY MESSAGES: Cohen syndrome patients' neutrophils display normal morphology and functions. Cohen syndrome patients' neutrophils have an increased rate of spontaneous apoptosis compared to healthy donors' neutrophils. No ER stress or defective ELA2 expression or glycosylation was observed in Cohen syndrome patients' neutrophils. SerpinB1 expression is significantly decreased in Cohen syndrome neutrophils as well as in VPS13B-deficient cells.

High-fat diet disturbs lipid raft/TGF-ß signaling-mediated maintenance of hematopoietic stem cells in mouse bone marrow.

Despite recent in vivo data demonstrating that high-fat diet (HFD)-induced obesity leads to major perturbations in murine hematopoietic stem cells (HSC), the direct role of a HFD is not yet completely understood. Here, we investigate the direct impact of a short-term HFD on HSC and hematopoiesis in C57BL/6J mice compared with standard diet-fed mice. We detect a loss of half of the most primitive HSC in the bone marrow (BM) cells of HFD-fed mice, which exhibit lower hematopoietic reconstitution potential after transplantation. Impaired maintenance of HSC is due to reduced dormancy after HFD feeding. We discover that a HFD disrupts the TGF-ß receptor within lipid rafts, associated to impaired Smad2/3-dependent TGF-ß signaling, as the main molecular mechanism of action. Finally, injecting HFD-fed mice with recombinant TGF-ß1 avoids the loss of HSC and alteration of the BM's ability to recover, underscoring the fact that a HFD affects TGF-ß signaling on HSC.

HSP27 is a partner of JAK2-STAT5 and a potential therapeutic target in myelofibrosis.

Heat shock protein 27 (HSP27/HSPB1) is a stress-inducible chaperone that facilitates cancer development by its proliferative and anti-apoptotic functions. The OGX-427 antisense oligonucleotide against HSP27 has been reported to be beneficial against idiopathic pulmonary fibrosis. Here we show that OGX-427 is effective in two murine models of thrombopoietin- and JAKV617F-induced myelofibrosis. OGX-427 limits disease progression and is associated with a reduction in spleen weight, in megakaryocyte expansion and, for the JAKV617F model, in fibrosis. HSP27 regulates the proliferation of JAK2V617F-positive cells and interacts directly with JAK2/STAT5. We also show that its expression is increased in both CD34+ circulating progenitors and in the serum of patients with JAK2-dependent myeloproliferative neoplasms with fibrosis. Our data suggest that HSP27 plays a key role in the pathophysiology of myelofibrosis and represents a new potential therapeutic target for patients with myeloproliferative neoplasms.

CD45 phosphatase is crucial for human and murine acute myeloid leukemia maintenance through its localization in lipid rafts.

CD45 is a pan-leukocyte protein with tyrosine phosphatase activity involved in the regulation of signal transduction in hematopoiesis. Exploiting CD45 KO mice and lentiviral shRNA, we prove the crucial role that CD45 plays in acute myeloid leukemia (AML) development and maintenance. We discovered that CD45 does not colocalize with lipid rafts on murine and human non-transformed hematopoietic cells. Using a mouse model, we proved that CD45 positioning within lipid rafts is modified during their oncogenic transformation to AML. CD45 colocalized with lipid rafts on AML cells, which contributes to elevated GM-CSF signal intensity involved in proliferation of leukemic cells. We furthermore proved that the GM-CSF/Lyn/Stat3 pathway that contributes to growth of leukemic cells could be profoundly affected, by using a new plasma membrane disrupting agent, which rapidly delocalized CD45 away from lipid rafts. We provide evidence that this mechanism is also effective on human primary AML samples and xenograft transplantation. In conclusion, this study highlights the emerging evidence of the involvement of lipid rafts in oncogenic development of AML and the targeting of CD45 positioning among lipid rafts as a new strategy in the treatment of AML.

Trim33/Tif1γ is involved in late stages of granulomonopoiesis in mice.

Trim33/Tif1γ (Trim33) is a member of the tripartite motif family. Using a conditional hematopoietic-specific Trim33 knock-out (Trim33(Δ/Δ)) mouse, we showed previously that Trim33 deficiency in hematopoietic stem cells leads to severe defects in hematopoiesis, resembling the main features of human chronic myelomonocytic leukemia. We also demonstrated that Trim33 is involved in hematopoietic aging through TGFß signaling. Nevertheless, how Trim33 contributes to the terminal stages of myeloid differentiation remains to be clarified. We reveal here the crucial role of Trim33 expression in the control of mature granulomonocytic differentiation. An important component of Trim33-deficient mice is the alteration of myeloid differentiation, as characterized by dysplastic features, abnormal granulocyte and monocyte maturation, and the expansion of CD11b(+)Ly6G(high)Ly6C(low) myeloid cells, which share some features with polymorphonuclear-myeloid-derived suppressor cells. Moreover, in Trim33(Δ/Δ) mice, we observed the alteration of CSF-1-mediated macrophage differentiation in association with the lack of Csf-1 receptor. Altogether, these results indicate that Trim33 deficiency leads to the expansion of a subset of myeloid cells characterizing the myelodysplastic/myeloproliferative neoplasm.

A randomized phase II trial of azacitidine +/- epoetin-ß in lower-risk myelodysplastic syndromes resistant to erythropoietic stimulating agents.

The efficacy of azacitidine in patients with anemia and with lower-risk myelodysplastic syndromes, if relapsing after or resistant to erythropoietic stimulating agents, and the benefit of combining these agents to azacitidine in this setting are not well known. We prospectively compared the outcomes of patients, all of them having the characteristics of this subset of lower-risk myelodysplastic syndrome, if randomly treated with azacitidine alone or azacitidine combined with epoetin-ß. High-resolution cytogenetics and gene mutation analysis were performed at entry. The primary study endpoint was the achievement of red blood cell transfusion independence after six cycles. Ninety-eight patients were randomised (49 in each arm). Median age was 72 years. In an intention to treat analysis, transfusion independence was obtained after 6 cycles in 16.3% versus 14.3% of patients in the azacitidine and azacitidine plus epoetin-ß arms, respectively (P=1.00). Overall erythroid response rate (minor and major responses according to IWG 2000 criteria) was 34.7% vs. 24.5% in the azacitidine and azacitidine plus epoetin-ß arms, respectively (P=0.38). Mutations of the SF3B1 gene were the only ones associated with a significant erythroid response, 29/59 (49%) versus 6/27 (22%) in SF3B1 mutated and unmutated patients, respectively, P=0.02. Detection of at least one "epigenetic mutation" and of an abnormal single nucleotide polymorphism array profile were the only factors associated with significantly poorer overall survival by multivariate analysis. The transfusion independence rate observed with azacitidine in this lower-risk population, but resistant to erythropoietic stimulating agents, was lower than expected, with no observed benefit of added epoetin, (clinicaltrials.gov identifier: 01015352).

Evolution of procalcitonin, C-reactive protein and fibrinogen levels in neutropenic leukaemia patients with invasive pulmonary aspergillosis or mucormycosis.

Unlike bacterial infections, the value of procalcitonin (PCT) in detecting fungal infections in leukaemia patients is not clear. To determine whether the monitoring of PCT coupled with C-reactive protein (CRP) and fibrinogen (Fib) could be helpful in the management of pulmonary aspergillosis (IPA) or mucormycosis (PM), we retrospectively analysed the evolution of PCT, CRP and Fib levels in 94 leukaemia patients with proven/probable IPA (n = 77) or PM (n = 17) from D-12 to D12 relative to IFI onset defined as D0. Overall, 2140 assays were performed. From D-12 to D0, 12%, 5% and 1.4% of patients had PCT >0.5, 1 and 1.5 µg l(-1) , respectively, while CRP was >50, 75 and 100 mg l(-1) in 84%, 70% and 57% and Fib was >4, 5 and 6 g l(-1) in 96%, 80% and 61% of cases respectively (P < 10(-7) ). The same trends were observed from D1 to D12. Overall, between D-12 and D12, only 6.4% of patients had PCT >1.5 µg l(-1) , while CRP >100 mg l(-1) and Fib >6 g l(-1) were observed in 80% and 75% of cases respectively (P < 10(-7) ). In leukaemia patients, IPA or PM was accompanied by a significant increase in CRP and Fib while PCT remained low.