Search Results (128)

Clonal hematopoiesis (CH) is the expansion of clones from a single hematopoietic stem cell (HSC) in the bone marrow. Clonal hematopoiesis of indeterminate potential (CHIP) refers to CH defined by the presence of pre-leukemic driver mutations in at least 2% of alleles in sequenced peripheral blood. This phenomenon is, by definition, associated not only with the future development of acute myeloid leukemia but also with non-malignant conditions, including cardiovascular disease. However, the underlying molecular mechanisms for CH in non-malignant diseases, such as cardiovascular disease, are not fully explained. Certain subtypes of CHIP may give rise to proinflammatory immune cells, which, in turn, may promote atherosclerosis progression. Key subtypes of CHIP include mutations in genes encoding epigenetic regulators DNMT3A (DNA methyltransferase 3A), TET2 (ten-eleven translocation methylcytosine dioxygenase 2), and ASXL1 (associated sex combs-like 1), as well as mutations in the gene encoding hematopoietic cytokine signaling: JAK2 (Janus kinase 2). The aim of this review is to summarize the current knowledge of CHIP and its association with inflammation and cardiovascular risk factors. Full article

T-cell non-Hodgkin lymphomas, which arise from post-thymic mature T cells, constitute approximately 10–15% of all non-Hodgkin lymphomas. Their leukemic presentations, referred to here as mature T-cell leukemias, are relatively uncommon and present significant diagnostic and therapeutic challenges requiring an informed approach to diagnosis and management. The initial presentation is often persistent T-cell lymphocytosis that must be distinguished from reactive (non-malignant) causes. Unlike B-cell lymphocytosis, where clonality usually indicates malignancy, T-cell clonality can be detected in benign conditions such as autoimmune disorders and viral infections. Thus, establishing clonality is helpful but not sufficient, and a systematic diagnostic approach integrating clinical features, morphology, immunophenotype, and molecular findings is critical. This review outlines our approach to the diagnosis and treatment of four major subtypes of mature T-cell leukemias: T-cell prolymphocytic leukemia (T-PLL), adult T-cell leukemia/lymphoma (ATLL), T-large granular lymphocytic leukemia (T-LGL), and Sézary syndrome (SS). Each section includes a discussion of clinical features, workup, and treatment options. Full article

Acute myeloid leukemia (AML) remains a therapeutically challenging malignancy due to high relapse rates driven by leukemic stem cells (LSCs) and adaptive resistance mechanisms. Emerging evidence positions autophagy as a central regulator of AML pathobiology, exerting context-dependent effects that suppress leukemogenesis during disease initiation yet sustain LSC survival and chemoresistance in established AML. Mechanistically, autophagy integrates mitochondrial quality control, lipid droplet turnover, and metabolic rewiring to support oxidative phosphorylation, particularly under hypoxic bone marrow conditions. Lipophagy-driven fatty acid oxidation has emerged as a key metabolic vulnerability distinguishing LSCs from normal hematopoietic stem cells. Furthermore, non-coding RNAs critically modulate autophagy networks, reinforcing therapy resistance. Preclinical and clinical studies demonstrate that both inhibition and activation of autophagy may yield therapeutic benefit depending on genetic context, mutational landscape, and disease stage. We propose that integrating multi-omics approaches, particularly lipidomics, with artificial intelligence and machine learning will enable precise identification of autophagy-dependent AML subsets. Rational, biomarker-guided modulation of autophagy may overcome resistance while preserving normal hematopoiesis, offering a path toward personalized metabolic targeting in AML. Full article

Background: In acute myeloid leukemia (AML), the most sensitive measurable residual disease (MRD) methods are single-gene approaches, but these are applicable only in ~60% of AML cases. Methods: We applied multi-omics single-cell analysis on diagnostic and first remission samples to identify leukemia-specific molecular markers for subsequent MRD monitoring in six AML patients lacking AML-defining variants. Results: Five selection criteria were defined to identify suitable MRD markers. Markers of primordial leukemic clones were identified by combining data from single-cell sequencing and immunophenotyping. Specific markers suitable for use in MRD follow-up were identified in 6/6 patients, in some cases in myelodysplasia-related genes and clonal hematopoiesis-related genes usually not recommended for use in MRD determinations. Patient-specific ddPCR (limits of detection: 0.06–0.0011%) or EC-NGS assays correlated with therapeutic responses: 0/4 markers displayed molecular relapses in three non-relapsing patients, contrary to 4/4 markers of three relapsing patients. Of these, 3/4 and 1/4 markers detected molecular relapses earlier than or simultaneous with conventional methods, respectively (−115 to −338 days). Conclusions: Our results demonstrate that single-cell subclonal mapping at diagnosis and during first remission enables selection of reliable MRD targets for personalized disease surveillance in patients lacking conventional MRD markers. Full article

Therapy resistance remains a major cause of relapse and poor outcomes in acute lymphoblastic leukemia (ALL). Recent multi-omics studies in ALL have revealed that resistance arises from a combination of leukemia-specific genetic lesions, treatment-driven clonal evolution, and adaptive non-genetic programs. Genomic analyses have identified recurrent alterations associated with resistance to chemotherapy, tyrosine kinase inhibitors, and immunotherapies, while single-cell profiling has uncovered heterogeneous cell states that persist during treatment and contribute to minimal residual disease. Emerging epigenetic, proteomic, and metabolic data further indicate that reversible regulatory and signaling changes play a central role in leukemic persistence. Integrative analyses are beginning to define convergent resistance pathways and clinically relevant biomarkers, although longitudinal sampling and clinical translation remain limited. This review summarizes the current multi-omics landscape of therapy resistance in ALL and discusses opportunities to improve risk stratification and therapeutic strategies. Full article

The search for new therapeutic principles is essential for treating relapsed/refractory (r/r) acute myeloid leukemia (AML). Novel principles include genome-agnostic differentiation induction, controlling AML-triggering inflammation, potentiating the immune response and ‘normalizing’ AML metabolism. This review summarizes data from a phase I study (10 patients, pts) and three case reports reporting 7 pts on the treatment of r/r AML by reprogramming AML hallmarks using APA, low-dose azacitidine, pioglitazone (PPARα/γ agonist) and all-trans retinoic acid. APA reprograms the r/r AML phenotype in patients with clinically and molecularly/genetically unfavorable risk profiles (17 pts, 16 refractory, one relapsed) in a genome-agnostic manner, restoring the plasticity of AML hallmarks, thereby improving immune surveillance, attenuating inflammation-triggered promotion of AML and distant microbial inflammation (healing of fungal pneumonia during induction of complete remission (CR) with APA), while normalizing leukemia metabolism (restoring phagocytosis and ROS production in leukemic neutrophils). APA induces CR in 10 pts (59%), with only modest hematotoxicity following CR induction. This allows treatment to be carried out in an outpatient setting, including for elderly and comorbid patients. Triple transcriptional modulation, facilitated by epigenetic modelling with azacitidine, targets reprogramming of non-oncogene addiction networks in AML, re-establishing functionally active, closely interrelated myeloid hallmarks and AML cell death genome-agnostically. Full article

The clinical features and outcomes of adult acute leukemia (AL)-associated hemophagocytic lymphohistiocytosis (AL-HLH) remain insufficiently characterized. We retrospectively analyzed 45 adult patients diagnosed with AL-HLH between December 2019 and June 2023. Among 746 AL patients, 45 developed HLH, with 40 developing acute myeloid leukemia (AML), 4 developing acute lymphoblastic leukemia (ALL), and 1 developing mixed-phenotype acute leukemia (MPAL). According to the ELN 2022 criteria, 16 (35.6%) had favorable, 3 (6.7%) had interediate, and 26 (57.7%) had poor risk. At the time of HLH onset, seven (15.6%) patients were in composite complete remission (CCR), and 38 (84.4%) were in non-CCR states; 25 (55.6%) patients were newly diagnosed before induction chemotherapy. The HLH-94/04-based regimens (etoposide and dexamethasone) with or without ruxolitinib achieved an ORR (overall remission rate) of 82.2% and a CR rate of 66.7%. After anti-leukemic therapy, 60% (27/45) of patients achieved CCR for leukemia (including patients in CCR at HLH onset and those achieving CCR after treatment). Hematopoietic stem cell transplantation (HSCT) independently predicted sustained remission. The estimated overall rates at 6 and 12 months after HLH diagnosis were 73.1% and 59.2%, respectively. Multivariate Cox analysis identified failure to achieve CCR for leukemia as the only independent adverse prognostic factor. AL-HLH is an uncommon but severe complication that predominantly occurs in AML patients with poor-risk cytogenetics or active disease. Early recognition, effective HLH control, and achievement of CCR in AL are crucial for improving patient prognosis. Full article

In vitro cytotoxicity of three (E)-3-(4′-X-benzylidene)-1-indanones (2a-c) displayed lower cytotoxicity towards murine P388 and L1210 leukemic cells as well as human Molt 4/C8 and CEM T-lymphocytes than the respective six- (3a-c) and seven-membered (4a-c) analogs. To study whether thiol reactivity—as a possible basis of their mechanism of action—correlates with the observed cytotoxicities, kinetics of the non-enzyme catalyzed reactions with reduced glutathione (GSH) and N-acetylcysteine (NAC) of 2a-c were investigated. Furthermore, it was also the aim of the work to compare the thiol reactivity of the open-chain chalcones (1) and their carbocyclic analogs (2-4) with different ring sizes (n = 5–7). The reactivity of the compounds and the stereochemical outcome of the reactions were evaluated using high-pressure liquid chromatography–mass spectrometry (HPLC-MS). Molecular modeling calculations were performed to rationalize the high initial rate and low conversion of the 2a indanone in comparison with those of the carbocyclic analog tetralone (3a) and benzosuberone (4a). Thiol reactivity and cancer cell cytotoxicity showed a dependence on both the ring size and the nature of aromatic substituents. Full article

Leukemia stem cells (LSCs) in numerous hematologic malignancies are generally believed to be responsible for disease initiation, progression/relapse and resistance to chemotherapy. It has been shown that non-leukemic hematopoietic cells are affected molecularly and biologically by leukemia cells in the same bone marrow environment where both non-leukemic hematopoietic stem cells (HSCs) and LSCs reside. We believe the molecular and biological changes of these non-leukemic HSCs should be accompanied by the morphological changes of these cells. On the other hand, the quantity of these non-leukemic HSCs with morphological changes should reflect disease severity, prognosis and therapy responses. Thus, identification of non-leukemic HSCs in the leukemia bone marrow environment and monitoring of their quantity before, during and after treatments will potentially provide valuable information for correctly handling treatment plans and predicting outcomes. However, we have known that these morphological changes at the stem cell level cannot be extracted and identified by microscopic visualization with human eyes. In this study, we chose polycythemia vera (PV) as a disease model (a type of human myeloproliferative neoplasms derived from a hematopoietic stem cell harboring the JAK2V617F oncogene) to determine whether we can use artificial intelligence (AI) deep learning to identify and quantify non-leukemic HSCs obtained from bone marrow of JAK2V617F knock-in PV mice by analyzing single-cell images. We find that non-JAK2V617F-expressing HSCs are distinguishable from LSCs in the same bone marrow environment by AI with high accuracy (>96%). More importantly, we find that non-JAK2V617F-expressing HSCs from the leukemia bone marrow environment of PV mice are morphologically distinct from normal HSCs from a normal bone marrow environment of normal mice by AI with an accuracy of greater than 98%. These results help us prove the concept that non-leukemic HSCs undergo AI-recognizable morphological changes in the leukemia bone marrow environment and possess unique morphological features distinguishable from normal HSCs, providing a possibility to assess therapy responses and disease prognosis through identifying and quantitating these non-leukemic HSCs in patients. Full article

The cause of nephrotic–nephritic syndrome and elevated blood pressure values was investigated by renal biopsy in a 72-year-old Caucasian male with B-cell chronic lymphocytic leukemia (B-CLL) and a low level of IgG/lambda paraprotein. Double-contoured glomerular capillaries, glomerular thrombi, interstitial B-CLL infiltrates, and normal-looking arteries and arterioles were observed histologically. The glomerular capillaries displayed nonspecific entrapment of IgM and C3 and pseudolinear C4d positivity immunohistochemically. With electron microscopy, diffusely effaced foot processes, widened and duplicated glomerular basement membrane (BM), mesangial cell interposition, and thickened, non-fenestrated, and serrated endothelial cells located on subendothelial BM layer(s) were seen. The peritubular capillaries lacked any significant BM multilayering. Chronic glomerular thrombotic microangiopathy (TMA) was diagnosed; the C4d positivity result indicated structural remodeling of glomerular capillary walls. Laboratory features of microangiopathic hemolytic anemia were absent. The functional complement assay found selective classical pathway activation and the consumption of early complement components. The components of the alternative pathway were not consumed. A disease-causing variant in the coding region of the complement C2 gene was screened, with negative results. The kidney function gradually deteriorated to stage 4 chronic kidney disease over a period of six months. Second-line treatment with ibrutinib markedly decreased the leukemic symptoms, stopped the production of paraprotein, and eliminated the nephrotic syndrome; the kidney function improved. The decreased activity of the classical pathway remained unchanged. The culprit of glomerular anomalies seemed to be the paraprotein, which acted as a nephrotoxic mediator and triggered glomerular TMA. A hypothetical pathophysiologic explanation of TMA is presented. The paraneoplastic classical pathway activation of complement did not play any role in the development of glomerular TMA. Full article

Acute promyelocytic leukemia (APL) is a rare subtype of acute myeloid leukemia (AML) characterized by chromosomal translocation forming the fusion protein that blocks the differentiation of myeloid progenitors and increases the self-renewal of leukemia cells. The introduction of all-trans retinoic acid (ATRA) and arsenic trioxide (ATO) has dramatically improved outcomes in APL, making it a leading example of successful treatment through differentiation of cancer cells. However, life-threatening side effects and treatment resistance may develop; therefore, modulation of the safety and efficacy of these drugs may contribute to further improving treatment results. Recently, zinc, involved in the structure and function of transcription factors, has received special attention for its potential role in the development and treatment response of cancer. Zinc homeostasis is disrupted in APL, with intracellular accumulation stabilizing oncogenic proteins. Zinc depletion promotes degradation of PML–RARA and induces apoptosis, while supplementation enhances genotoxic stress in leukemic cells but protects normal hematopoiesis. Zinc also regulates key transcription factors involved in differentiation and proliferation, including RUNX2, KLF4, GFI1, and CREB. In this review, we examine how zinc may impact zinc-finger (ZnF) and non-ZnF transcription factors and differentiation therapy in APL, thereby identifying potential strategies to enhance treatment efficacy and minimize side effects. Full article

The development of FGFR1-driven stem cell leukemia and lymphoma syndrome (SCLL) in mouse models is accompanied by an increase in highly heterogenous myeloid derived suppressor cells (MDSCs), which promote immune evasion. To dissect this heterogeneity, we used a combination of CyTOF and scRNA-Seq to define the phenotypes and genotypes of these MDSCs. CyTOF demonstrated increased levels of circulating macrophages in the peripheral blood of leukemic mice, and flow cytometry demonstrated that these macrophages were derived from Ly6C^Hi M-MDSC as well as the Ly6C^Int and Ly6C^Low monocytic populations. Consistently, scRNA-Seq analysis demonstrated the accumulation of non-classical monocytes (ncMono) during leukemia progression, which also express macrophage markers. These leukemia-induced macrophages show continuous transcriptional reprogramming during leukemia progression, with the upregulation of cellular stress response genes Hspa1a and Hspa1b and inflammation-related gene Nfkbia. Trajectory analysis revealed a transition from classical monocytes (cMono) to ncMono, and potential genes orchestrating this transition process have been identified. Furthermore, T-cell suppression assays demonstrated the immune suppressive abilities of leukemia-induced circulatory macrophages. Targeting these macrophages with the GW2580 CSF1R inhibitor leads to restored immune surveillance and improved survival. Overall, we demonstrate that circulating macrophages are responsible, at least in part, for the immune suppression in SCLL leukemia models, and targeting macrophages in this system improves the survival of leukemic mice. Full article

Acute myeloid leukemia (AML) proliferation is significantly influenced by the interactions between leukemia blasts and the bone marrow (BM) microenvironment. Specifically, bone marrow mesenchymal stem cells (BMSCs) derived from AML patients (AML-MSCs) are known to support leukemia growth and facilitate disease progression. Studies have demonstrated that the transfer of mitochondria from MSCs to AML blasts not only aids in disease progression but also contributes to chemotherapy resistance. Furthermore, BM stromal cells can trigger a metabolic shift in malignant cells from mitochondrial respiration to glycolysis, which enhances both growth and chemo-resistance. This study focuses on identifying transcriptional and metabolic alterations in AML-MSCs to uncover potential targeted therapies for AML. We employed RNA sequencing and microarray analysis on MSCs cocultured with leukemic cells (MLL-AF9) and on MSCs isolated from both non-leukemic and MLL-AF9 leukemic mice. The Gene Set Enrichment Analysis (GSEA) indicated a significant downregulation of gene sets associated with oxidative phosphorylation and glycolysis in AML-MSCs. Furthermore, coculture of MSCs from wild-type mice (WT-MSCs) and a healthy donor individual (HD-MSCs) with AML cells demonstrated reduced oxidative phosphorylation and glycolysis. These metabolic changes were consistent in AML-MSCs derived from both leukemic mice and patients. Our results indicate that AML cells diminish the metabolic capacity of MSCs, specifically targeting oxidative phosphorylation and glycolysis. These findings suggest potential metabolic vulnerabilities that could be exploited to develop more effective therapeutic strategies for AML. Full article

The enzyme γ-glutamyl transpeptidase (GGT), located on the surface of cellular membranes, hydrolyzes extracellular glutathione (GSH) to guarantee the recycling of cysteine and maintain intracellular redox homeostasis. High expression levels of GGT on tumor cells are associated with increased cell proliferation and resistance against chemotherapy. Therefore, GGT inhibitors have potential as adjuvants in treating GGT-positive tumors; however, most have been abandoned during clinical trials due to toxicity. Recent studies indicate marine-derived ovothiols as more potent non-competitive GGT inhibitors, inducing a mixed cell-death phenotype of apoptosis and autophagy in GGT-overexpressing cell lines, such as the chronic B leukemic cell HG-3, while displaying no toxicity towards non-proliferative cells. In this work, we characterize the activity of two synthetic ovothiol analogs, L-5-sulfanylhistidine and iso-ovothiol A, in GGT-positive cells, such as HG-3 and HL-60 cells derived from acute promyelocytic leukemia. The two compounds inhibit the activity of membrane-bound GGT, without altering cell vitality nor inducing cytotoxic autophagy in HG-3 cells. We provide evidence that a portion of L-5-sulfanylhistidine enters HG-3 cells and acts as a redox regulator, contributing to the increase in intracellular GSH. On the other hand, ovothiol A, which is mostly sequestered by external membrane-bound GGT, induces intracellular ROS increase and the consequent autophagic pathways. These findings provide the basis for developing ovothiol derivatives as adjuvants in treating GGT-positive tumors’ chemoresistance. Full article

The Wnt signaling pathway plays a critical role in regulating normal hematopoiesis and immune cell development. However, its dysregulation has emerged as a key driver of leukemogenesis. Leukemic stem cells exploit aberrant Wnt signaling to sustain self-renewal, evade apoptosis, and promote unchecked proliferation. In this review, we highlight the dual roles of canonical and non-canonical Wnt pathways in acute leukemia, emphasizing their distinct and overlapping contributions to disease progression. We also evaluate current preclinical and clinical strategies targeting Wnt signaling, identifying both promising advances and persistent obstacles to therapeutic translation. By elucidating the molecular mechanisms underlying Wnt pathway dysregulation in leukemic cells, this review underscores the potential of Wnt-directed therapies as a novel class of interventions to improve outcomes for patients with acute leukemia. Full article