An updated outlook on autophagy mechanism and how it supports acute myeloid leukemia maintenance.

The gradual acquisition of genetic and epigenetic disturbances bestows malignant traits upon hematopoietic stem cells, subverting them into a founder and reservoir cell for de novo acute myeloid leukemia (AML) known as leukemic stem cells (LSC). Beyond its molecular heterogeneity, AML is also characterized by rewiring biological processes to support its onset and maintenance. LSC were observed to inherently and actively trigger mitochondrial turnover through selective autophagic removal such that impairing the process led to cell differentiation at the expense of its stemness.

Potency and efficacy of pharmacological PIP4K2 inhibitors in acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL), a complex malignancy, displays varying expression profiles of PIP4K2-related genes in adult patients. While PIP4K2A expression is elevated in ALL bone marrow cells compared to healthy bone marrow cells, PIP4K2B is downregulated, and PIP4K2C remains relatively unchanged. Despite the correlation between increased PIP4K2A expression and increased percentage of peripheral blood blasts, clinical outcomes do not strongly correlate with the expression of these genes.

A 4-gene prognostic index for enhancing acute myeloid leukaemia survival prediction.

Despite advancements in utilizing genetic markers to enhance acute myeloid leukaemia (AML) outcome prediction, significant disease heterogeneity persists, hindering clinical management. To refine survival predictions, we assessed the transcriptome of non-acute promyelocytic leukaemia chemotherapy-treated AML patients from five cohorts (n = 975). This led to the identification of a 4-gene prognostic index (4-PI) comprising CYP2E1, DHCR7, IL2RA and SQLE.

BMP6 and VDR gene polymorphisms are associated with osteonecrosis in a sickle cell anaemia cohort.

The occurrence and severity of osteonecrosis in sickle cell anaemia (SCA) vary due to risk factors, including genetic modifiers. Bone morphogenetic proteins (BMPs), particularly BMP6, and the vitamin D receptor (VDR) play key roles in cartilage and bone metabolism, making them potential contributors to orthopaedic outcomes in SCA. Here, we evaluated the association of polymorphisms in BMP6 (rs3812163, rs270393 and rs449853) and VDR (FokI rs2228570 and Cdx2 rs11568820) genes with osteonecrosis risk in a Brazilian SCA cohort.

Acute myeloid leukemia-derived bone marrow mesenchymal cells exhibit improved support for leukemic cell proliferation.

Introduction: The bone marrow (BM) microenvironment plays a significant role in acute myeloid leukemia (AML) genesis and there is evidence that BM mesenchymal stromal cells (BMMSCs) can support leukemia progenitor cell proliferation and survival and provide resistance to cytotoxic therapies.

Hypothesis And Method: Nevertheless, currently unknown are the relevance of the spatial localization of AML cells relative to the BMMSCs and whether BMMSCs from patients with AML and healthy subjects have similar properties. To address these issues, we performed a differential gene expression analysis using RNA-sequencing data generated from healthy donors (HDs) and leukemic BMMSCs.

Pharmacological Inhibition of PIP4K2 Potentiates Venetoclax-Induced Apoptosis in Acute Myeloid Leukemia.

Phosphatidylinositol-5-phosphate 4-kinase type 2 (PIP4K2) protein family members (PIP4K2A, PIP4K2B, and PIP4K2C) participate in the generation of PIP,P, which acts as a secondary messenger in signal transduction, a substrate for metabolic processes, and has structural functions. In patients with acute myeloid leukemia (AML), high and levels are independent markers of a worse prognosis. Recently, our research group reported that THZ-P1-2 (PIP4K2 pan-inhibitor) exhibits anti-leukemic activity by disrupting mitochondrial homeostasis and autophagy in AML models.

A-296G variant of THBS1 gene (rs1478605) is associated with a lower frequency of stroke in a Brazilian population with sickle cell anemia.

Stroke is a devastating clinical outcome that significantly contributes to the morbidity and mortality of sickle cell anemia (SCA) patients. Despite its advantages in predicting stroke risk, transcranial Doppler screening has limitations that restrict its applicability, highlighting the need for emerging prognostic tools. Thrombospondin-1 plays a crucial role in endothelial injury, platelet adhesion, and nitric oxide metabolism and may be implicated in stroke pathophysiology.

The nonessential amino acid cysteine is required to prevent ferroptosis in acute myeloid leukemia.

Cysteine is a nonessential amino acid required for protein synthesis, the generation of the antioxidant glutathione, and for synthesizing the nonproteinogenic amino acid taurine. Here, we highlight the broad sensitivity of leukemic stem and progenitor cells to cysteine depletion. By CRISPR/CRISPR-associated protein 9-mediated knockout of cystathionine-γ-lyase, the cystathionine-to-cysteine converting enzyme, and by metabolite supplementation studies upstream of cysteine, we functionally prove that cysteine is not synthesized from methionine in acute myeloid leukemia (AML) cells.

Prognostic implications of the ID1 expression in acute myeloid leukemia patients treated in a resource-constrained setting.

Introduction: The aberrant expression of the inhibitor of DNA binding (ID1) gene has been frequently associated with the leukemogenesis and prognostication acute myeloid leukemia (AML), although its clinical importance has never been investigated in patients treated outside well-controlled clinical trials.

Methods: Using quantitative real-time polymerase chain reaction, we investigated the role of the ID1 expression in the clinical outcomes of non-selected patients with acute myeloid leukemia treated in a real-life setting.

Results: Overall, 128 patients were enrolled.

M2 macrophages drive leukemic transformation by imposing resistance to phagocytosis and improving mitochondrial metabolism.

It is increasingly becoming clear that cancers are a symbiosis of diverse cell types and tumor clones. Combined single-cell RNA sequencing, flow cytometry, and immunohistochemistry studies of the innate immune compartment in the bone marrow of patients with acute myeloid leukemia (AML) reveal a shift toward a tumor-supportive M2-polarized macrophage landscape with an altered transcriptional program, with enhanced fatty acid oxidation and NAD generation. Functionally, these AML-associated macrophages display decreased phagocytic activity and intra-bone marrow coinjection of M2 macrophages together with leukemic blasts strongly enhances in vivo transformation potential.

The PIP4K2 inhibitor THZ-P1-2 exhibits antileukemia activity by disruption of mitochondrial homeostasis and autophagy.

The treatment of acute leukemia is challenging because of the genetic heterogeneity between and within patients. Leukemic stem cells (LSCs) are relatively drug-resistant and frequently relapse. Their plasticity and capacity to adapt to extracellular stress, in which mitochondrial metabolism and autophagy play important roles, further complicates treatment.

Dietary methionine starvation impairs acute myeloid leukemia progression.

Targeting altered tumor cell metabolism might provide an attractive opportunity for patients with acute myeloid leukemia (AML). An amino acid dropout screen on primary leukemic stem cells and progenitor populations revealed a number of amino acid dependencies, of which methionine was one of the strongest. By using various metabolite rescue experiments, nuclear magnetic resonance-based metabolite quantifications and 13C-tracing, polysomal profiling, and chromatin immunoprecipitation sequencing, we identified that methionine is used predominantly for protein translation and to provide methyl groups to histones via S-adenosylmethionine for epigenetic marking.

Inhibition of the succinyl dehydrogenase complex in acute myeloid leukemia leads to a lactate-fuelled respiratory metabolic vulnerability.

Metabolic programs can differ substantially across genetically distinct subtypes of acute myeloid leukemia (AML). These programs are not static entities but can change swiftly as a consequence of extracellular changes or in response to pathway-inhibiting drugs. Here, we uncover that AML patients with FLT3 internal tandem duplications (FLT3-ITD) are characterized by a high expression of succinate-CoA ligases and high activity of mitochondrial electron transport chain (ETC) complex II, thereby driving high mitochondrial respiration activity linked to the Krebs cycle.

The Glycolytic Gatekeeper PDK1 defines different metabolic states between genetically distinct subtypes of human acute myeloid leukemia.

Acute myeloid leukemia remains difficult to treat due to strong genetic heterogeneity between and within individual patients. Here, we show that Pyruvate dehydrogenase kinase 1 (PDK1) acts as a targetable determinant of different metabolic states in acute myeloid leukemia (AML). PDK1 AMLs are OXPHOS-driven, are enriched for leukemic granulocyte-monocyte progenitor (L-GMP) signatures, and are associated with FLT3-ITD and NPM1cyt mutations.

Phenformin increases early hematopoietic progenitors in the Jak2 murine model.

Background: Myeloproliferative neoplasms (MPN) are disorders characterized by an alteration at the hematopoietic stem cell (HSC) level, where the JAK2 mutation is the most common genetic alteration found in classic MPN (polycythemia vera, essential thrombocythemia, and primary myelofibrosis). We and others previously demonstrated that metformin reduced splenomegaly and platelets counts in peripheral blood in JAK2 pre-clinical MPN models, which highlighted the antineoplastic potential of biguanides for MPN treatment. Phenformin is a biguanide that has been used to treat diabetes, but was withdrawn due to its potential to cause lactic acidosis in patients.

STMN1 is highly expressed and contributes to clonogenicity in acute promyelocytic leukemia cells.

Stathmin 1 (STMN1) is a microtubule-destabilizing protein highly expressed in hematological malignancies and involved in proliferation and differentiation. Although a previous study found that the PML-RARα fusion protein, which contributes to the pathophysiology of acute promyelocytic leukemia (APL), positively regulates STMN1 at the transcription and protein activity levels, little is known about the role of STMN1 in APL. In this study, we aimed to investigate the STMN1 expression levels and their associations with laboratory, clinical, and genomic data in APL patients.

The ratio of ATP11C/PLSCR1 mRNA transcripts has clinical significance in sickle cell anemia.

One of the physiologic mechanisms responsible to maintain asymmetric phospholipid distribution (in particular phosphatidylserine, PS) in human erythrocyte membranes is orchestrated by the balance between enzymes responsible for active transport of PS from the outer to the inner leaflet (ATP11C) and those whose counteracts these activities (PLSCR1). Using quantitative real-time polymerase chain reaction and standard flow cytometry procedures, we hypothesized that the aberrant expression of either or both ATP11C and PLSCR1 transcripts may disrupt the PS internalization/externalization process and become clinically relevant for patients with sickle cell anemia (SCA). Overall, neither ATP11C/PLSCR1 ratio or ATP11C and PLSCR1 (if analyzed separately) had impact on risk to present acute or chronic organ damage in 178 patients with SCA.

The Combination of Gefitinib With ATRA and ATO Induces Myeloid Differentiation in Acute Promyelocytic Leukemia Resistant Cells.

In approximately 15% of patients with acute myeloid leukemia (AML), total and phosphorylated EGFR proteins have been reported to be increased compared to healthy CD34 samples. However, it is unclear if this subset of patients would benefit from EGFR signaling pharmacological inhibition. Pre-clinical studies on AML cells provided evidence on the pro-differentiation benefits of EGFR inhibitors when combined with ATRA or ATO .