Prognostic impact of DNMT3A mutation in acute myeloid leukemia with mutated NPM1

Prognostic impact; Mutation; Acute myeloid leukemiaImpacte pronòstic; Mutació; Leucèmia mieloide agudaImpacto pronóstico; Mutación; Leucemia mieloide agudaThe negative prognostic impact of internal tandem duplication of FLT3 (FLT3-ITD) in patients with acute myeloid leukemia with mutated NPM1 (AML-NPM1) is restricted to those with a higher FLT3-ITD allelic ratio (FLT3high; ≥0.5) and considered negligible in those with a wild-type (FLT3WT)/low ITD ratio (FLT3low). Because the comutation of DNMT3A (DNMT3Amut) has been suggested to negatively influence prognosis in AML-NPM1, we analyzed the impact of DNMT3Amut in FLT3-ITD subsets (absent, low, and high ratios). A total of 164 patients diagnosed with AML-NPM1 included in 2 consecutive CETLAM protocols and with DNMT3A and FLT3 status available were studied. Overall, DNMT3Amut status did not have a prognostic impact, with comparable overall survival (P = .2). Prognostic stratification established by FLT3-ITD (FLT3WT = FLT3low > FLT3high) was independent of DNMT3Amut status. Measurable residual disease (MRD) based on NPM1 quantitative polymerase chain reaction was available for 94 patients. DNMT3Amut was associated with a higher number of mutated NPM1 transcripts after induction (P = .012) and first consolidation (C1; P < .001). All DNMT3Amut patients were MRD+ after C1 (P < .001) and exhibited significant MRD persistence after C2 and C3 (MRD+ vs MRD−; P = .027 and P = .001, respectively). Finally, DNMT3Amut patients exhibited a trend toward greater risk of molecular relapse (P = .054). In conclusion, DNMT3Amut did not modify the overall prognosis exerted by FLT3-ITD in AML-NPM1 despite delayed MRD clearance, possibly because of MRD-driven preemptive intervention.This work was supported in part by the Biomedical Research Institute (IIB Sant-Pau) and the José Carreras Leukemia Research Institute as well as grants from the Catalan Government (PERIS SLT002/16/0043 and AGAUR 2017 SGR 139) and the Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Spain (PI17/01246, PI20/01621 and CM20/00061)

Imatinib and dasatinib as salvage therapy for sclerotic chronic graft-vs-host disease.

Aim To assess the toxicity, tolerance, steroid-sparing capacity, effectiveness, and response rate to imatinib and dasatinib for the treatment of severe sclerotic chronic graft-vs-host disease (scGVHD). Methods This retrospective study analyzed 8 consecutive patients with severe refractory scGVHD who received salvage therapy with imatinib. Patients intolerant and/or refractory to imatinib received dasatinib treatment. Results 7 patients discontinued imatinib treatment (1 achieved complete response, 5 were resistant and/or intolerant, and 1 developed grade IV neutropenia) and 1 patient achieved prolonged partial response, but died due to an infectious complication while on treatment 5 patients started dasatinib treatment (3 achieved partial responses and discontinued dasatinib, 1 achieved a durable partial response, but died due to a consecutive rapid pulmonary cGVHD progression and 1 with stable disease discontinued treatment due to gastroenteric intolerance). The response rate (partial and/or complete responses) for severe scGVHD was 25% for imatinib and 60% for dasatinib. Conclusion In our series, dasatinib was better tolerated, safer, steroid-sparing, and had a low incidence of infectious complications, which suggests that it may be a more effective therapeutic alternative for patients with refractory scGVHD than imatinib. Treatment of scGVHD with effective antifibrotic drugs such as TKI, which block the kinase fibrotic pathway, may be a safe and effective therapeutic option, but further studies are needed to confirm our findings

European LeukemiaNet 2017 risk stratification for acute myeloid leukemia: validation in a risk-adapted protocol

Risk stratification; Acute myeloid leukemiaEstratificació del risc; Leucèmia mieloide agudaEstratificación de riesgo; Leucemia mieloide agudaThe 2017 European LeukemiaNet (ELN 2017) guidelines for the diagnosis and management of acute myeloid leukemia (AML) have become fundamental guidelines to assess the prognosis and postremission therapy of patients. However, they have been retrospectively validated in few studies with patients included in different treatment protocols. We analyzed 861 patients included in the Cooperativo Para el Estudio y Tratamiento de las Leucemias Agudas y Mielodisplasias-12 risk-adapted protocol, which indicates cytarabine-based consolidation for patients allocated to the ELN 2017 favorable-risk group, whereas it recommends allogeneic stem cell transplantation (alloSCT) as a postremission strategy for the ELN 2017 intermediate- and adverse-risk groups. We retrospectively classified patients according to the ELN 2017, with 327 (48%), 109 (16%), and 245 (36%) patients allocated to the favorable-, intermediate-, and adverse-risk group, respectively. The 2- and 5-year overall survival (OS) rates were 77% and 70% for favorable-risk patients, 52% and 46% for intermediate-risk patients, and 33% and 23% for adverse-risk patients, respectively. Furthermore, we identified a subgroup of patients within the adverse group (inv(3)/t(3;3), complex karyotype, and/or TP53 mutation/17p abnormality) with a particularly poor outcome, with a 2-year OS of 15%. Our study validates the ELN 2017 risk stratification in a large cohort of patients treated with an ELN-2017 risk-adapted protocol based on alloSCT after remission for nonfavorable ELN subgroups and identifies a genetic subset with a very poor outcome that warrants investigation of novel strategies.This study was supported (in part) by Fondo de Investigaciones Sanitarias/Instituto de Salud Carlos III (ISCIII) grants PI16/01027, PI19/1476, and PI20/01621; Health Research and Innovation Strategic Plan (PERIS) grant SLT002/16/00433 and research group support SGR 1395 and SGR 1655 from Generalitat de Catalunya; resident award “Emili Letang” 2019 (Hospital Clínic de Barcelona); and “Beca de Investigación FEHH 2019” (Fundación Española de Hematologia y Hemoterapia)

Immunodiagnostic tests' predictive values for progression to tuberculosis in transplant recipients. A prospective cohort study

Background: Little is known about the predictive value for progression to tuberculosis (TB) of interferon-γ release assays and how they compare with the tuberculin skin test (TST) in assessing the risk of TB infection in transplant recipients. Methods: We screened 50 liver transplant (LT) and 26 hematopoietic stem cell transplant (HSCT) recipients with both QuantiFERON-TB Gold In-tube (QFT-GT) and TST and prospectively followed them for a median of 47 months without preventive chemoprophylaxis. Results: In the LT cohort, 1 in 22 (4.5%) QFT-GT-positive patients developed posttransplant TB, compared with none of the QFT-GT-negative patients. In the HSCT cohort, none of the 7 QFT-GT-positive patients developed TB, whereas 1 case (5.3%) progressed to active TB among the 19 QFT-GT-negative patients. Comparable results were obtained with the TST: in the LT group, 1 of 23 TST-positive and none of the 27 TST-negative patients developed TB; and in the HSCT group, none of the 8 TST-positive and one of the 18 TST-negative patients progressed to active TB. Conclusions: In this cohort of transplant recipients, the positive predictive value of QFT-GT for progression to active TB was low and comparable to that of TST. Although the risk of developing TB in patients with negative results at baseline is very low, some cases may still occur

Imatinib and dasatinib as salvage therapy for sclerotic chronic graft-vs-host disease

Aim To assess the toxicity, tolerance, steroid-sparing capacity, effectiveness, and response rate to imatinib and dasatinib for the treatment of severe sclerotic chronic graftvs- host disease (scGVHD). Methods This retrospective study analyzed 8 consecutive patients with severe refractory scGVHD who received salvage therapy with imatinib. Patients intolerant and/or refractory to imatinib received dasatinib treatment. Results 7 patients discontinued imatinib treatment (1 achieved complete response, 5 were resistant and/or intolerant, and 1 developed grade IV neutropenia) and 1 patient achieved prolonged partial response, but died due to an infectious complication while on treatment. 5 patients started dasatinib treatment (3 achieved partial responses and discontinued dasatinib, 1 achieved a durable partial response, but died due to a consecutive rapid pulmonary cGVHD progression and 1 with stable disease discontinued treatment due to gastroenteric intolerance). The response rate (partial and/or complete responses) for severe scGVHD was 25% for imatinib and 60% for dasatinib. Conclusion In our series, dasatinib was better tolerated, safer, steroid-sparing, and had a low incidence of infectious complications, which suggests that it may be a more effective therapeutic alternative for patients with refractory scGVHD than imatinib. Treatment of scGVHD with effective antifibrotic drugs such as TKI, which block the kinase fibrotic pathway, may be a safe and effective therapeutic option, but further studies are needed to confirm our findings

Administration of taurolidine-citrate lock solution for prevention of central venous catheter infection in adult neutropenic haematological patients: a randomised, double-blinded, placebo-controlled trial (TAURCAT)

Background: Catheter-related bloodstream infection (CRBSI) is one of the most frequent complications in patients with cancer who have central venous catheters (CVCs) implanted and is associated with substantial morbidity and mortality. Taurolidine is a non-antibiotic agent with broad-spectrum antimicrobial activity, which has been used as a lock solution to prevent CRBSI in some settings. However, little is known about its usefulness in high-risk adult neutropenic patients with cancer. This prospective randomised clinical trial aims to test the hypothesis that taurolidine-citrate lock solution is more effective than placebo for preventing catheter infection in neutropenic haematological patients.Methods: This study is a prospective, multicentre, randomised, double-blinded, parallel, superiority, placebo-controlled trial. Patients with haematological cancer who are expected to develop prolonged neutropenia (>7 days) and who have a non-tunnelled CVC implanted will be randomised to receive prophylactic taurolidine-citrate-heparin solution using a lock technique (study group) or heparin alone (placebo group). The primary endpoint will be bacterial colonisation of the CVC hubs. The secondary endpoints will be the incidence of CRBSI, CVC removal, adverse events, and 30-day case-fatality rate.Discussion: The lock technique is a preventive strategy that inhibits bacterial colonisation in the catheter hubs, which is the initial step of endoluminal catheter colonisation and the development of infection. Taurolidine is a nontoxic agent that does not develop antibiotic resistance because it acts as an antiseptic rather than an antibiotic. Taurolidine has shown controversial results in the few trials conducted in cancer patients. These studies have important limitations due to the lack of data on adult and/or high-risk neutropenic patients, the type of catheters studied (tunnelled or ports), and the lack of information regarding the intervention (e.g. dwelling of the solution, time, and periodicity of the lock technique). If our hypothesis is proven, the study could provide important solid evidence on the potential usefulness of this preventive procedure in a population at high risk of CRBSI, in whom this complication may significantly impair patient outcome

Efficacy of extended infusion of beta-lactam antibiotics for the treatment of febrile neutropenia in haematologic patients: protocol for a randomised, multicentre, open-label, superiority clinical trial (BEATLE)

Background: Febrile neutropaenia (FN) is a very common complication in patients with haematological malignancies and is associated with considerable morbidity and mortality. Broad-spectrum antipseudomonal beta-lactam antibiotics (BLA) are routinely used for the treatment of cancer patients with FN. However, the clinical efficacy of BLA may be diminished in these patients because they present with pathophysiological variations that compromise the pharmacokinetic (PK) parameters of these antibiotics. Optimised administration of BLA in prolonged infusions has demonstrated better clinical outcomes in critically ill patients. However, there is a paucity of data on the usefulness of this strategy in patients with FN. The aim of this study is to test the hypothesis that the administration of BLA would be clinically more effective by extended infusion (EI) than by intermittent infusion (II) in haematological patients with FN. Methods: A randomised, multicentre, open-label, superiority clinical trial will be performed. Patients with haematological malignancies undergoing chemotherapy or haematopoietic stem-cell transplant and who have FN and receive empirical antibiotic therapy with cefepime, piperacillin-tazobactam or meropenem will be randomised (1:1) to receive the antibiotic by EI (during half the time of the dosing interval) in the study group, or by II (30 min) in the control group. The primary endpoint will be clinical efficacy, defined as defervescence without modifying the antibiotic treatment administered within the first 5 days of therapy. The primary endpoint will be analysed in the intention-to-treat population. The secondary endpoints will be pharmacokinetic/pharmacodynamic (PK/PD) target achievement, bacteraemia clearance, decrease in C-reactive protein, overall (30-day) case-fatality rate, adverse events and development of a population PK model of the BLA studied. Discussion: Data on the usefulness of BLA administration in patients with FN are scant. Only three clinical studies addressing this issue have been published thus far, with contradictory results. Moreover, these studies had some methodological flaws that limit the interpretation of their findings. If this randomised, multicentre, phase IV, open-label, superiority clinical trial validates the hypothesis that the administration of BLA is clinically more effective by EI than by II in haematological patients with FN, then the daily routine management of these high-risk patients could be changed to improve their outcomes

The Origins and the Biological Consequences of the Pur/Pyr DNA·RNA Asymmetry

We analyze the physical origin and the chemical and biological consequences of the asymmetry that occurs in DNA·RNA hybrids when the purine/pyrimidine (Pu/Py) ratio is different in the DNA and RNA strands. When the DNA strand of the hybrid is Py rich, the duplex is much more stable, rigid, and A-like than when the DNA strand is Pu rich. The origins of this dramatic asymmetry are double: first, the apparently innocuous substitution dT → rU produces a significant decrease in stacking, and second, backbone distortions are larger for DNA(Pu)·RNA(Py) hybrids than for the mirror RNA(Pu)·DNA(Py) ones. The functional impact of the structural and dynamic asymmetry in the biological activities of hybrids is dramatic and can be used to improve the efficiency of antisense-type strategies on the basis of the degradation of hybrids by RNase H or gene editing using CRISPR-Cas9 technology

Evolution of selenophosphate synthetases: emergence and relocation of function through independent duplications and recurrent subfunctionalization

Selenoproteins are proteins that incorporate selenocysteine (Sec), a nonstandard amino acid encoded by UGA, normally a stop codon. Sec synthesis requires the enzyme Selenophosphate synthetase (SPS or SelD), conserved in all prokaryotic and eukaryotic genomes encoding selenoproteins. Here, we study the evolutionary history of SPS genes, providing a map of selenoprotein function spanning the whole tree of life. SPS is itself a selenoprotein in many species, although functionally equivalent homologs that replace the Sec site with cysteine (Cys) are common. Many metazoans, however, possess SPS genes with substitutions other than Sec or Cys (collectively referred to as SPS1). Using complementation assays in fly mutants, we show that these genes share a common function, which appears to be distinct from the synthesis of selenophosphate carried out by the Sec- and Cys- SPS genes (termed SPS2), and unrelated to Sec synthesis. We show here that SPS1 genes originated through a number of independent gene duplications from an ancestral metazoan selenoprotein SPS2 gene that most likely already carried the SPS1 function. Thus, in SPS genes, parallel duplications and subsequent convergent subfunctionalization have resulted in the segregation to different loci of functions initially carried by a single gene. This evolutionary history constitutes a remarkable example of emergence and evolution of gene function, which we have been able to trace thanks to the singular features of SPS genes, wherein the amino acid at a single site determines unequivocally protein function and is intertwined to the evolutionary fate of the entire selenoproteome

Targeting prohibitins induces apoptosis in acute myeloid leukemia cells

Fluorizoline is a new synthetic molecule that induces apoptosis by selectively targeting prohibitins (PHBs). In this study, the pro-apoptotic effect of fluorizoline was assessed in two cell lines and 21 primary samples from patients with debut of acute myeloid leukemia (AML). Fluorizoline induced apoptosis in AML cells at concentrations in the low micromolar range. All primary samples were sensitive to fluorizoline irrespectively of patients' clinical or genetic features. In addition, fluorizoline inhibited the clonogenic capacity and induced differentiation of AML cells. Fluorizoline increased the mRNA and protein levels of the pro-apoptotic BCL-2 family member NOXA both in cell lines and primary samples analyzed. These results suggest that targeting PHBs could be a new therapeutic strategy for AM