WT1-guided pre-emptive therapy after allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia.

Measurable residual disease (MRD)-guided pre-emptive therapies are now widely used to prevent post-transplant hematological relapse in patients with acute myeloid leukemia (AML). This single-center retrospective study aimed to clarify the significance of pre-emptive treatment based on Wilms' tumor gene-1 mRNA (WT1) monitoring for MRD in patients with AML who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). Patients with AML who received chemotherapy for hematological relapse or WT1 increase after allo-HSCT were eligible for inclusion. From January 2017 to June 2022, 30 patients with a median age of 57 (16-70) years were included and stratified into two groups: 10 with WT1 increase and 20 with hematological relapse. The median times from HCT to WT1 increase or hematological relapse were 309 days (range: 48-985) or 242 days (range: 67-1116), respectively. Less intensive chemotherapy using azacitidine or cytarabine was selected for all patients with WT1 increase and 12 (60%) with hematological relapse. The 1-year overall survival and event-free survival rates for WT1 increase and hematological relapse were 70% vs. 44% (P = 0.024) and 70% vs. 29% (P = 0.029), respectively. These real-world data suggest that WT1-guided pre-emptive therapy may be superior to therapy after hematological relapse in patients with AML who have undergone allo-HSCT.

Association of Leukemia With ABO Blood Group Distribution and Discrepancy: A Review Article.

The ABO system is an essential blood group in clinical transfusion medicine implicated in several human diseases. The ABO system has been investigated for over a century, with various studies exploring potential links to disease susceptibility. The study examines the possible relationship between leukemia and the distribution and the ABO blood group system discrepancy. A comprehensive review was conducted on the recommended databases to review the ABO blood groups, their association with leukemia, and the expected changes in blood groups among leukemia patients. The study highlights different kinds of leukemia, such as acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and chronic lymphocytic leukemia (CLL), their characteristics, and their relationship with ABO blood groups. The document concludes that studying ABO blood group distributions among leukemia patients showed that the most common blood group in acute leukemia is the A group, while in chronic leukemia, the O group is predominant; more studies are required. This study also confirmed an association between leukemia and ABO blood group discrepancy.

The Potential Role of NOD2/CARD15 Genotype as a Prognostic Indicator for Bone Marrow Transplantation Outcomes in Patients With Acute Lymphoblastic Leukemia and Acute Myeloid Leukemia: A Systematic Review.

Hematopoietic stem-cell transplantation (HSCT) has emerged as a groundbreaking therapeutic option for acute myeloid leukemia (AML) and specific subtypes of acute lymphoblastic leukemia (ALL). The prognostic significance of the NOD2/CARD15 gene has been explored alongside various factors, encompassing diverse patient cohorts and gene variants. Siblings and unrelated donors used for stem cell transplantation exhibit significant associations between their genetic variations and graft-versus-host disease incidence. The transplantation of stem cells for leukemia patients involves numerous considerations, including patient survival, relapse rates, disease stage, donor and recipient ages, and compatibility. This study delved into research on the NOD2/CARD15 gene and its mutations to assess its suitability as a screening tool. A comprehensive literature search encompassing PubMed, ScienceDirect, and Google Scholar articles yielded 4,840 articles. After removing duplicates and applying inclusion and exclusion criteria, we narrowed the search results to 876 articles. Subsequent screening of abstracts and titles resulted in the selection of 230 relevant articles. Further exclusion of 198 articles unrelated to the research question led to the scrutinizing of 32 full-text articles, which were assessed against inclusion and exclusion criteria. Emphasis was placed on articles that specifically investigated the role of NOD2/CARD15 as a predictive factor for HSCT outcomes, ultimately resulting in the inclusion of 19 articles in this study. Single nucleotide polymorphisms (SNPs) such as NOD2 and CARD15 have demonstrated their potential as reliable genetic markers for predicting post-transplantation relapse and disease outcomes. Patients positive for these genetic markers have exhibited reduced overall survival and event-free survival and increased transplant-related mortality. Interventions with interferon-gamma and muramyl tripeptide phosphatidylethanolamine have been considered to mitigate the inflammatory effects of these SNPs, thus enhancing the influence of natural killer cells on abnormal cells and potentially extending patient survival. NOD2/CARD15 typing may aid in identifying patients at higher risk for relapse and improving their clinical outcomes after allogeneic stem cell transplant, particularly in ALL patients. However, no remarkable change was observed in AML patients. Additionally, this study underscores the pivotal roles of adaptive and innate immune responses and their interplay in stem cell transplant immunology.

Minimal residual disease monitoring in acute myeloid leukemia: Focus on MFC-MRD and treatment guidance for elderly patients.

Acute myeloid leukemia (AML) is distinguished by clonal growth of myeloid precursor cells, which impairs normal hematopoiesis. Minimal residual disease (MRD) refers to the residual leukemia cells that persist after chemotherapy. Patients who test positive for MRD have a higher likelihood of experiencing a recurrence, regardless of the specific chemotherapy approach used. Multi-parameter flow cytometry (MFC), polymerase chain reaction (PCR), and next-generation sequencing (NGS) are commonly employed techniques for identifying MRD. In the context of AML, patients are frequently monitored for measurable residual disease via multi-parameter flow cytometry (MFC-MRD). In order to explore recent advancements in AML and MRD diagnosis, an extensive search of the PubMed database was conducted, focusing on relevant research in the past 20 years. This review aims to examine various MRD monitoring methods, the optimal time points for assessment, as well as different specimen types used. Additionally, it underscores the significance of MFC-MRD assessment in guiding the treatment of elderly AML.

Iron Overload in Children with Acute Lymphoblastic and Acute Myeloblastic Leukemia-Experience of One Center.

Transfusions of packed red blood cells (PRBCs), given due to an oncological disease and its acute complications, are an indispensable part of anticancer therapy. However, they can lead to post-transfusion iron overload. The study aim was to evaluate the role of ferritin as a nonspecific marker of leukemic growth and marker of transfusion-related iron overload. We performed a longitudinal study of PRBC transfusions and changes in ferritin concentrations during the oncological treatment of 135 patients with childhood acute lymphoblastic and acute myeloblastic leukemia (ALL and AML, median age 5.62 years). At the diagnosis, 41% of patients had a ferritin level over 500 ng/mL, and 14% of patients had a ferritin level over 1000 ng/mL. At the cessation of the treatment, 80% of the children had serum ferritin (SF) over 500 ng/mL, and 31% had SF over 1000 ng/mL. There was no significant difference between SF at the beginning of the treatment between ALL and AML patients, but children with AML finished treatment with statistically higher SF. AML patients had also statistically higher number of transfusions. We found statistically significant positive correlations between ferritin and age, and weight and units of transfused blood. Serum ferritin at the moment of diagnosis can be a useful marker of leukemic growth, but high levels of SF are connected with iron overload in both AML and ALL.

Impact of different chemotherapy regimens on intestinal mucosal injury assessed with bedside ultrasound: a study in 213 AML patients.

Introduction: Neutropenic enterocolitis (NEC) is a life-threatening complication reported in patients with acute myeloid leukemia (AML) following chemotherapy (CHT). Intensive induction and consolidation CHT may damage intestinal mucosa leading to a NEC episode (NECe). NEC reported mortality may be up to 30-60%. Early US-guided bed-side diagnosis and prompt treatment may substantially improve the survival. An emerging worldwide concern is the intestinal colonization by multi-drug-resistant bacteria especially when patients are exposed to chemotherapy regimens potentially correlated to mucosal damage. Methods: In our study we prospectively enrolled all AML patients admitted in our leukemia unit to receive intensive induction and consolidation chemotherapy and experiencing chemotherapy-induced-neutropenia (CHTN). Results and discussion: Overall, we enrolled N=213 patients from 2007 to March 2023. We recorded N=465 CHTN, and N=42 NECe (9.0% incidence). The aim of our study was to assess which chemotherapy regimens are more associated with NEC. We found that ALM1310, followed by 7 + 3 (daunorubicin), 7 + 3 (idarubicin), 5 + 3 + 3 (cytarabine, etoposide, idarubicin), and AML1310 (consolidation) were associated with a statistically higher incidence of NEC. We did not detect NEC episodes in patients treated with CPX-351, 5 + 2 (cytarabine, idarubicine), and high-dose cytarabine. Thus, we found that cytarabine could determine mucosal damage when associated with an anthracycline but not if delivered either alone or as dual-drug liposomal encapsulation of daunorubicin/cytarabine. We also describe NEC mortality, symptoms at diagnosis, intestinal sites involvement, and prognostic significance of bowel wall thickening.

Human Umbilical Cord Mesenchymal Stem Cell-Derived Microvesicles Could Induce Apoptosis and Autophagy in Acute Myeloid Leukemia.

Background: Microvesicles (MV) have been identified as candidate biomarkers for treating acute myeloid leukemia (AML). This study investigated the effects of human umbilical cord-derived mesenchymal stem cell (hUCMSC)-derived MVs on apoptosis and autophagy in the KG-1 leukemic cell line. Methods: The hUCMSCs were cultured and characterized by flow cytometry. MVs were isolated by ultracentrifugation, and the concentration was determined using the Bradford method. The characteristics of MVs were confirmed using transmission electron microscopy, flow cytometry, and dynamic light scattering methods. KG-1 cells were treated with the desired concentrations of MVs for 24 h. The apoptosis induction and reactive oxygen species production were evaluated using flow cytometry. RT-PCR was performed to evaluate apoptosis- and autophagy-related genes expression. Results: Following tretment of KG-1 cells with 25, 50, and 100 µg/ml concentrations of MVs, the apoptosis rates were 47.85%, 47.15%, and 51.35% (p < 0.0001), and the autophagy-induced ROS levels were 73.9% (p < 0.0002), 84.8% (p < 0.0001), and 85.4% (p < 0.0001), respectively. BAX and ATG7 gene expression increased significantly at all concentrations compared to the control, and this level was higher at 50 µg/ml than that of the other concentrations. In addition, LC3 and Beclin 1 expression increased significantly in a concentration-dependen manner. Conversely, BCL2 expression decreased compared to the control. Conclusion: Our findings indicate that hUCMSC-MVs could induce cell death pathways of autophagy and apoptosis in the KG-1 cell lines and exert potent antiproliferative and proapoptotic effects on KG-1 cells in vitro. Therefore, hUCMSC-MVs may be a potential approach for cancer therapy as a novel cell-to-cell communication strategy.

Transforming Acute Myeloid Leukemia Treatment Through Next-Generation Sequencing: A Single-Center Experience.

In the last decade, advancements in understanding the genetic and molecular mechanisms of acute myeloid leukemia (AML) have significantly improved treatment options. Techniques such as immunophenotyping, cytogenetics, and next-generation sequence (NGS) testing are now standard practices for patient assessments, allowing for personalized therapies based on individual patient needs. Our study aimed to evaluate the impact of cytogenetics and NGS on initial treatment decisions for AML at our institution. We analyzed the frequency of alternative therapy choices that could have been made with complete molecular and cytogenetic information and compared overall survival rates between patient groups. We also analyzed the turnaround time for result generation. Our retrospective study evaluated 39 AML patients treated at our university hospital from June 2020 to June 2022, excluding classic acute promyelocytic leukemia cases. Patients with incomplete data or concurrent hematological malignancies were excluded. We collected data on admission blood counts, European LeukemiaNet (ELN) risk stratification, Charlson score, treatment type, and timing of cytogenetics and NGS results. Patients were categorized into 'standard' or 'other therapy' groups based on their molecular and cytogenetic profiles in accordance with NCCN guidelines. Our main goal was to determine how often NGS and cytogenetics results could have influenced induction therapy choices. Secondary objectives included comparing overall survival rates and analyzing report turnaround times for NGS and cytogenetics. Our study found that out of the 39 AML patients, 17 were in the "standard" group, and 22 were in the "other therapy" group. The standard group had an average age of 62.59 years, an average time to chemotherapy initiation of 8.29 days, and an overall survival (OS) rate of 428.12 days. The other therapy group had an average age of 61.86 years, an average time to chemotherapy initiation of six days, and an OS rate of 258.64 days. There was a significant difference in survival rates between the two groups (p=0.009). According to the ELN stratification, the standard group had 11 patients at intermediate risk and six at adverse risk. In contrast, the other therapy group had seven at intermediate risk, four at good risk, and 11 at adverse risk. NGS revealed mutations in 58.97% of patients. Our study suggests that almost half of the patients could have been treated differently if complete molecular and cytogenetic information had been available before therapy initiation, highlighting the potential for more personalized treatments. Additionally, our results showed significant differences in overall survival rates between standard treatment and alternative therapy groups. Our findings emphasize the importance of timely NGS and cytogenetics result generation, guiding institutions to allocate resources for effective patient care.

Cuproptosis-related lncRNAs as potential biomarkers of AML prognosis and the role of lncRNA HAGLR/miR-326/CDKN2A regulatory axis in AML.

Acute myeloblastic leukemia (AML) is the most prevalent form of AML in adults. Despite the availability of various treatment options, including radiotherapy and chemotherapy, many patients fail to respond to treatment or relapse. Copper is a necessary cofactor for all organisms; however, it turns toxic when concentrations reach a certain threshold maintained by homeostatic systems that have been conserved through evolution. However, the mechanism through which excess copper triggers cell death remains unknown. In this study, data on long non-coding RNAs (lncRNAs) related to cuproptosis were retrieved from publicly available databases. LASSO and univariate and multivariate Cox regression analyses were performed to establish an lncRNA model associated with cuproptosis specific to AML. To investigate the risk model, the Kaplan-Meier curve, principal component analysis, functional enrichment analysis, and nomographs were employed. The underlying clinicopathological characteristics were determined, and drug sensitivity predictions against the model were identified. Six cuproptosis-related lncRNA-based risk models were identified as the independent prognostic factors. By regrouping patients using a model-based method, we were able to more accurately differentiate patients according to their responses to immunotherapy. In addition, prospective compounds targeting AML subtypes have been identified. Using qRT-PCR, we examined the expression levels of six cuproptosis-associated lncRNAs in 30 clinical specimens. The cuproptosis-associated lncRNA risk-scoring model developed herein has implications in monitoring AML prognosis and in the clinical prediction of the response to immunotherapy. Furthermore, we identified and verified the ceRNA of the cuproptosis-related lncRNA HAGLR/miR-326/CDKN2A regulatory axis using bioinformatic tools. HAGLR is highly expressed in AML and AML cell lines. HAGLR inhibition significantly reduced the proliferation of AML cells and promoted apoptosis. Elesclomol promotes the degradation of CDKN2A and inhibits the proliferation of AML cells. Elesclomol combined with si-HAGLR inhibited the AML progression of AML both in vitro and in vivo.

Cytomegalovirus keratitis in acute myeloblastic leukemia.

A 58-year-old woman presented with acute myeloblastic leukemia (AML) developed a bilateral dendritic epithelial keratitis without retinitis. The patient was initially treated with oral acyclovir with a possible diagnosis of herpes simplex virus (HSV) keratitis. Polymerase chain reaction (PCR) was performed on ocular discharge specimens collected by soft-tipped applicators reported as cytomegalovirus (CMV). Then, acyclovir was discontinued and bilateral CMV keratitis was treated with IV ganciclovir and her epithelial lesions gradually disappeared. The current case report confirms that CMV is capable of generating corneal epithelial engagement without retina involvement and demonstrated that CMV keratitis is an emergent problem of AML. Therefore, in any case with bilateral corneal herpes keratitis, the patient should be evaluated for immune system deficiency.

Bridging to transplant and post-transplant maintenance therapy with FLT3 inhibitors in patients with relapsed or refractory FLT3 mutated acute myeloid leukemia.

OBJECTIVES AND METHODS: This single-center retrospective study was performed to evaluate the safety and efficacy of FMS-like tyrosine kinase 3 (FLT3) inhibitors before and after allogeneic hematopoietic cell transplantation (HCT) in relapsed/refractory patients with FLT3-mutation positive acute myeloid leukemia (AML). RESULTS: Ten patients who met the eligibility criteria were included. Eight of them achieved hematological remission at HCT, within a median span of 79 days (range: 43-197). In post-HCT, patients started maintenance therapy (MT; median time-to-start 79 days, range: 43-197), and the median duration of MT was 390 days (range: 67-815). Grade 3 hematological adverse events (AEs) were found in two patients, and non-hematological AEs were found in five patients. Nine patients underwent either dose reduction, discontinuation of therapy, or a switch to another FLT3 inhibitor due to AEs. Disease relapse occurred in one patient during MT. At the time of the last follow-up, seven patients are alive and disease-free, while three have died due to infection or transplant complications. CONCLUSION: In relapsed/refractory FLT3 mutation-positive AML, the use of FLT3 inhibitors can lead to high response rates and provide a safe bridge from HCT to MT. If sufficient attention is paid to safety, this therapy is expected to prevent disease relapse even with reduced dosages.

[Prognostic value of residual disease detection in acute myeloid leukemia with normal karyotype and negative FLT3-ITD]. / Intérêt pronostique de la détection de la maladie résiduelle dans les leucémies aiguës myéloïdes avec caryotype normal et FLT3-ITD négatif.

INTRODUCTION: Complete remission (CR) in patients with acute myeloid leukemia (AML) is still morphologicaly defined, thus corresponding to a wide range of tumor burden. OBJECTIVES: we aimed to evaluate the residual disease (MRD) status in patients with AML, as well as perform a molecular analysis of the FLT3/ITD gene in patients with normal karyotype. MATERIAL AND METHODS: adult patients with AML, diagnosed according to the WHO 2016 criteria, were included. MRD was detected using flow cytometric techniques after induction treatment resulting in CR. RESULTS: thirty patients met our inclusion criteria. 83 % of them had an intermediate risk status, 67 % of which (20/30) having a normal karyotype. MRD and leukemic stem cell (LSC) positivity in this group was predominant with considerable decrease in benign progenitor count. The relapse-free survival (RFS) in the group of MRD negative patients with normal cytogenetics and non-mutated FLT3 gene was better than the RFS in all of our patients studied. CONCLUSION: MRD and LSC are powerful prognostic factors for relapse. They should be routinely integrated to guide better management of AML.

Updates on the Management of Acute Myeloid Leukemia.

Acute myeloid leukemia is a heterogeneous disease defined by a large spectrum of genetic aberrations that are potential therapeutic targets. New targeted therapies have changed the landscape for a disease with poor outcomes. They are more effective than standard chemotherapy with a good safety profile. For "fit patients" in first-line, the combination of gemtuzumab ozogamicin or midostaurin with intensive chemotherapy or Vyxeos is now considered the "standard of care" for selected patients. On the other hand, for "unfit patients", azacitidine-venetoclax has been consolidated as a frontline treatment, while other combinations with magrolimab or ivosidenib are in development. Nevertheless, global survival results, especially in relapsed or refractory patients, remain unfavorable. New immunotherapies or targeted therapies, such as Menin inhibitors or sabatolimab, represent an opportunity in this situation. Future directions will probably come from combinations of different targeted therapies ("triplets") and maintenance strategies guided by measurable residual disease.

Persistently high incidence rates of childhood acute leukemias from 2010 to 2017 in Mexico City: A population study from the MIGICCL.

Introduction: Over the years, the Hispanic population living in the United States has consistently shown high incidence rates of childhood acute leukemias (AL). Similarly, high AL incidence was previously observed in Mexico City (MC). Here, we estimated the AL incidence rates among children under 15 years of age in MC during the period 2010-2017. Methods: The Mexican Interinstitutional Group for the Identification of the Causes of Childhood Leukemia conducted a study gathering clinical and epidemiological information regarding children newly diagnosed with AL at public health institutions of MC. Crude age incidence rates (cAIR) were obtained. Age-standardized incidence rates worldwide (ASIRw) and by municipalities (ASIRm) were calculated by the direct and indirect methods, respectively. These were reported per million population <15 years of age; stratified by age group, sex, AL subtypes, immunophenotype and gene rearrangements. Results: A total of 903 AL cases were registered. The ASIRw was 63.3 (cases per million) for AL, 53.1 for acute lymphoblastic leukemia (ALL), and 9.4 for acute myeloblastic leukemia. The highest cAIR for AL was observed in the age group between 1 and 4 years (male: 102.34 and female: 82.73). By immunophenotype, the ASIRw was 47.3 for B-cell and 3.7 for T-cell. The incidence did not show any significant trends during the study period. The ASIRm for ALL were 68.6, 66.6 and 62.8 at Iztacalco, Venustiano Carranza and Benito Juárez, respectively, whereas, other municipalities exhibited null values mainly for AML. Conclusion: The ASIRw for childhood AL in MC is among the highest reported worldwide. We observed spatial heterogeneity of rates by municipalities. The elevated AL incidence observed in Mexican children may be explained by a combination of genetic background and exposure to environmental risk factors.

Chronic Subdural Hematoma Caused by Acute Myeloblastic Leukemia: A Case Report.

Chronic subdural hematoma, a common neurosurgical disease, is mostly caused by craniocerebral trauma. Chronic subdural hematoma caused by acute myeloblastic leukemia is rarely reported, and its pathogenesis and strategies for clinical treatment remain controversial. Here, we report a rare case of chronic subdural hematoma caused by acute myeloblastic leukemia. The patient's condition deteriorated quickly after admission, and emergency trepanation and drainage of the chronic subdural hematoma was performed, followed by oral administration of atorvastatin. The platelet levels continued to decrease during neurosurgical treatment. Bone marrow cytology, flow cytology, and karyotype analysis suggested acute myelocytic leukemia (AML). Then, the patient was transferred to the hematology department for chemotherapy treatment, during which there was no recurrence of hematoma. Chronic subdural hematoma caused by acute myeloblastic leukemia is a very rare disease. Surgery should be performed when the intracranial hematoma is more than 10 mm thick and the midline structures are displaced by more than 5 mm, and postoperative treatment should be supplemented with atorvastatin to prevent recurrence. Chemotherapy should be given promptly to treat leukemia after stabilization of neurological conditions.

Role of Acute Myeloid Leukemia (AML)-Derived exosomes in tumor progression and survival.

Acute myeloid leukemia (AML) is a quickly aggressive hematopoietic disorder that progress due to the accumulation and clonal expansion of immature myeloid cells. Despite the latest developments in AML treatment, repeated relapses and drug resistance remain one of the major challenges in treatment of leukemia. Currently, it is well known that the components of the tumor microenvironment such as cellular and non-cellular elements play a critical function in treatment failures of AML, also they are most common cause of complications including suppression of hematopoiesis. Exosomes are membrane-bound extracellular vesicles (EVs) that transfer signaling molecules and have attracted a large amount of attention due to their important role in inter-cellular communication in health and disease. Exosomes participate in the survival and chemoresistance of many leukemia through transferring their rich cargos of molecules including miRNAs, growth factors, and cytokines. The key producers of exosomes that mainly participate to AML pathogenesis are bone marrow mesenchymal stem cell (BMSCs) and AML cell themselves. These cells release an enormous number of exosomes that affect several target cells such as natural killer (NK) and hematopoietic stem cells to the development of leukemia proliferation and progression. In the present study, a comprehensive review of the literature has been done to briefly discuss the biology of exosomes and highlight the role of exosomes derived from AML in the progress of acute myeloid leukemia.

Metabolic dysregulation and emerging therapeutical targets for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is an aggressive human cancer with increasing incidence worldwide. Multiple efforts have been made to explore pharmaceutical therapies to treat HCC, such as targeted tyrosine kinase inhibitors, immune based therapies and combination of chemotherapy. However, limitations exist in current strategies including chemoresistance for instance. Tumor initiation and progression is driven by reprogramming of metabolism, in particular during HCC development. Recently, metabolic associated fatty liver disease (MAFLD), a reappraisal of new nomenclature for non-alcoholic fatty liver disease (NAFLD), indicates growing appreciation of metabolism in the pathogenesis of liver disease, including HCC, thereby suggesting new strategies by targeting abnormal metabolism for HCC treatment. In this review, we introduce directions by highlighting the metabolic targets in glucose, fatty acid, amino acid and glutamine metabolism, which are suitable for HCC pharmaceutical intervention. We also summarize and discuss current pharmaceutical agents and studies targeting deregulated metabolism during HCC treatment. Furthermore, opportunities and challenges in the discovery and development of HCC therapy targeting metabolism are discussed.

The m6A RNA methyltransferase METTL3/METTL14 promotes leukemogenesis through the mdm2/p53 pathway in acute myeloid leukemia.

N6-methyladenosine (m6A) is the most abundant internal modification in mammalian mRNA and recent studies have highlighted the importance of m6A levels in tumor development. In this study, we investigated the expression of methyltransferase-like 3 (METTL3) and 14 (METTL14), components of the RNA m6A methyltransferase complex, in samples from 89 patients with acute myeloid leukemia (AML), and followed the survival of 75 of these patients. Our results show that METTL3 and METTL14 are highly expressed in most of the patients with AML (except those with APL), and high levels of METTL3 and/or METTL14 correlated to shorter survival in the patients. In leukemia cell lines K562 and kasumi-1, both METTL3 and METTL14 promote cell proliferation and cell cycle, and the knockdown of METTL3 and METTL14 inhibits proliferation, and induces apoptosis and differentiation. Notably, the knockdown of METTL3 and METTL14 in K562 cell line leads to several changes in the expression of p53 signal pathway, including the upregulation of p53, cyclin dependent kinase inhibitor 1A (CDKN1A/p21), and downregulation of mdm2. Importantly, the m6A level of mdm2 mRNA was significant lower after knock-down of METTL3 and METTL14 examined by m6A-RIP and mdm2 qPCR assay, and the half-life of mdm2 under actinomycin-D treatment became shorter. Taken together, our study demonstrates that the lower m6A levels of mdm2 mRNA mediated by the knockdown of METTL3 and METTL14 could lead to the low stability of mdm2 mRNA transcripts and low expression of MDM2, in the end, activate p53 signal pathway. Both METTL3 and METTL14 play an oncogenic role in AML by targeting mdm2/p53 signal pathway.

Improved outcome in children compared to adolescents and young adults after allogeneic hematopoietic stem cell transplant for acute myeloid leukemia: a retrospective study from the Francophone Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC).

BACKGROUND: There are currently few data on the outcome of acute myeloid leukemia (AML) in adolescents after allogeneic HSCT. The aim of this study is to describe the outcome and its specific risk factors for children, adolescents and young adults after a first allogeneic HSCT for AML. METHODS: In this retrospective study, we compared the outcome of AML patients receiving a first allogeneic HSCT between 2005 and 2017 according to their age at transplantation's time: children (< 15 years, n = 564), adolescent and post-adolescent (APA) patients (15-25 years, n = 647) and young adults (26-40 years; n = 1434). RESULTS: With a median follow-up of 4.37 years (min-max 0.18-14.73 years), the probability of 2-year overall survival (OS) was 71.4% in children, 61.1% in APA patients and 62.9% in young adults (p = 0.0009 for intergroup difference). Both relapse and non-relapse mortality (NRM) Cumulative Incidence (CI) estimated at 2 years were different between the age groups (30.8% for children, 35.2% for APA patients and 29.4% for young adults-p = 0.0254, and 7.0% for children, 10.6% for APA patients and 14.2% for young adults, p < 0.0001; respectively). Whilst there was no difference between the three groups for grade I to IV acute GVHD CI at 3 months, the chronic GVHD CI at 2 years was higher in APA patients and young adults (31.4% and 36.4%, respectively) in comparison to the children (17.5%) (p < 0.0001). In multivariable analysis, factors associated with death were AML cytogenetics (HR1.73 [1.29-2.32] for intermediate risk 1, HR 1.50 [1.13-2.01] for intermediate risk 2, HR 2.22 [1.70-2.89] for high cytogenetics risk compared to low risk), use of TBI ≥ 8 Grays (HR 1.33 [1.09-1.61]), disease status at transplant (HR 1.40 [1.10-1.78] for second Complete Remission (CR), HR 2.26 [1.02-4.98] for third CR and HR 3.07 [2.44-3.85] for active disease, compared to first CR), graft source (HR 1.26 [1.05-1.50] for Peripheral Blood Stem Cells compared to Bone Marrow) and donor age (HR 1.01 (1-1.02] by increase of 1 year). CONCLUSION: Age is an independent risk factor for NRM and extensive chronic GVHD. This study suggests that APA patients with AML could be beneficially treated with a chemotherapy-based MAC regimen and bone marrow as a stem cells source.

Treatment Failure in Acute Myeloid Leukemia: Focus on the Role of Extracellular Vesicles.

Acute myeloblastic leukemia (AML) is one of the most common types of blood malignancies that results in an AML-associated high mortality rate each year. Several causes have been reported as prognostic factors for AML in children and adults, the most important of which are cytogenetic abnormalities and environmental risk factors. Following the discovery of numerous drugs for AML treatment, leukemic cells sought a way to escape from the cytotoxic effects of chemotherapy drugs, leading to treatment failure. Nowadays, comprehensive studies have looked at the role of extracellular vesicles (EVs) secreted by AML blasts and how the microenvironment of the tumor changes in favor of cancer progression and survival to discover the mechanisms of treatment failure to choose the well-advised treatment. Reports show that malignant cells secrete EVs that transmit messages to adjacent cells and the tumor's microenvironment. By secreting EVs, containing immune-inhibiting cytokines, AML cells inactivate the immune system against malignant cells, thus ensuring their survival. Also, increased secretion of EVs in various malignancies indicates an unfavorable prognostic factor and the possibility of drug resistance. In this study, we briefly reviewed the challenges of treating AML with a glance at the EVs' role in this process. It is hoped that with a deeper understanding of EVs, new therapies will be developed to eliminate the relapse of leukemic cells.