Search Results (492)

Myeloid malignancies exhibit profound metabolic dependence on mitochondrial oxidative phosphorylation (OXPHOS) for survival and proliferation. Antileukemic therapies such as Venetoclax combined with Azacitidine or cytarabine induce rapid mitochondrial collapse, disrupting electron transport, NADH oxidation, and ATP synthesis, followed by a selective rebound of fatty-acid oxidation (FAO) and redox-buffering programs that sustain minimal residual disease. This review integrates current mechanistic and clinical insights into therapy-induced mitochondrial suppression, delineates the regulatory circuitry that enables metabolic recovery, and frames these events as a reversible model of clinical energy deficiency. By linking mitochondrial stress signaling, lipid oxidation, and adaptive redox metabolism, we outline how bioenergetic reprogramming drives therapeutic resistance and propose interventions that target this adaptive axis in acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), and related myeloid neoplasms. Full article

Background: KMT2A partial tandem duplication (PTD) occurs in approximately 5–10% of acute myeloid leukemia (AML) cases and is associated with poor prognosis. While its cytogenetic and molecular features are well described, the immunophenotypic characteristics of AML with KMT2A-PTD remain incompletely defined. Methods: We identified 47 cases of AML with KMT2A-PTD by optical genome mapping. All cases underwent flow cytometric immunophenotypic analysis and next-generation sequencing using an 81-gene panel. Results: The cohort included 32 men and 15 women with a median age of 67 years (range, 19–87). Thirty-eight cases were de novo AML, and nine were secondary to myelodysplastic syndrome and/or myeloproliferative neoplasm. Most cases (93%) demonstrated a normal or non-complex karyotype. The most frequent mutations involved FLT3-ITD (47%), DNMT3A (43%), and RUNX1 (23%). Thirty-one cases (66%) were granulocytic, while 16 (34%) showed granulocytic and/or monocytic differentiation. Blasts uniformly expressed HLA-DR and frequently expressed CD117 (91%) and CD34 (79%). Increased expression of CD123 (74%) and CD117 (43%) and decreased expression of HLA-DR (74%) and CD38 (69%) were common. Aberrant CD25 expression was observed in 51% of cases. Increased CD123 and aberrant CD25 expression were significantly associated with FLT3-ITD mutations (both p < 0.0001) but not with other recurrent mutations. There was no correlation between FLT3-ITD mutation and expression levels of CD117, CD38 or HLA-DR (all p > 0.05). Conclusions: AML with KMT2A-PTD shows distinctive immunophenotypic features with increased CD123 and aberrant CD25 expression, both associated with FLT3-ITD. These markers may have diagnostic and therapeutic relevance in this AML subtype. Full article

Mutations in TP53 inhibit p53 protective behaviors including cell cycle arrest, DNA damage repair protein recruitment, and apoptosis. The ubiquity of p53 in genome-stabilizing functions leads to an aberrant tumor microenvironment in TP53-mutated myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Profound immunosuppression mediated by myeloid-derived suppressor cells, the upregulation of cytokines and cell-surface receptors on leukemic cells, the suppression of native immune regulator cells, and metabolic aberrations in the bone marrow are features of the TP53-mutated AML/MDS marrow microenvironment. These localized changes in the bone marrow microenvironment (BMME) explain why traditional therapies for MDS/AML, including chemotherapeutics and hypomethylating agents, are not as effective in TP53-mutated myeloid neoplasms and demonstrate the dire need for new treatments in this patient population. The unique pathophysiology of TP53-mutated disease also provides new therapeutic approaches which are being studied, including intracellular targets (MDM2, p53), cell-surface protein biologics (immune checkpoint inhibitors, BiTE therapy, and antibody–drug conjugates), cell therapies (CAR-T, NK-cell), signal transduction pathways (Hedgehog, Wnt, NF-κB, CCRL2, and HIF-1α), and co-opted biologic pathways (cholesterol synthesis and glycolysis). In this review, we will discuss the pathophysiologic anomalies of the tumor microenvironment in TP53-mutant MDS/AML, the hypothesized mechanisms of chemoresistance it imparts, and how novel therapies are leveraging diverse therapeutic targets to address this critical area of need. Full article

Myelodysplastic syndromes/neoplasms (MDS) are clonal hematopoietic disorders characterized by ineffective hematopoiesis, cytopenias, and a variable risk of progression to secondary acute myeloid leukemia (sAML). Despite major advances in the molecular and clinical characterization of MDS, mechanistic and translational research remains constrained by the limited availability of well-validated in vitro models. Many historically used cell lines are difficult to maintain, exhibit restricted proliferative capacity, or represent advanced disease stages rather than bona fide MDS, while others have been affected by misidentification or cross-contamination. This review provides a comprehensive and critical overview of currently available MDS and MDS-related cell lines, including MDS92, MDS-L and its sublines, M-TAT, TER-3, SKK-1, SKM-1, and MOLM-17/18. We summarize their clinical origin, cytogenetic and molecular features, growth factor dependence, differentiation capacity, and experimental applications, with particular emphasis on their relevance to disease stage, clonal evolution, and leukemic transformation. In addition, we discuss the controversy surrounding misidentified models such as PC-MDS and highlight the importance of rigorous cell line authentication. Full article

Myeloid neoplasms (MNs) with germline predisposition represent a distinct, increasingly recognized category in the WHO classification, encompassing myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) arising in the context of an inherited genetic alteration or mutation. While often presenting at a younger age or with characteristic cytopenias with or without organ dysfunction, some can manifest in adulthood, highlighting the need for vigilance regardless of age or family history. Key predisposing genes include transcription factors (e.g., RUNX1, CEBPA) and genes involved in RNA splicing and telomere biology disorders. Identification of these germline mutations is critical as MNs with germline predisposition dictate specific therapeutic strategies—particularly for hematopoietic stem cell transplantation (HSCT)—and require genetic counseling and surveillance for at-risk relatives. Accurate diagnosis often requires non-hematopoietic germline DNA testing, which provides important biological insights into the development of different myeloid neoplasms and directs personalized patient care. Full article

Background: Higher-risk myelodysplastic syndromes (HR-MDS) carry a high risk of progression to acute myeloid leukemia and poor overall survival. Hypomethylating agents (HMAs), such as azacitidine, remain the standard of care but have limited efficacy. A 15-day venetoclax-azacitidine regimen has shown promising objective response rates (ORR) and potential as a bridge to allogeneic hematopoietic stem cell transplantation (HSCT) in relapsed/refractory HR-MDS. We conducted a prospective multicenter trial to evaluate its efficacy and safety in previously untreated patients. Methods: This multicenter prospective study enrolled treatment-naïve HR-MDS patients (IPSS-R > 3.5). Venetoclax was administered on days 1–15 (escalated from 100 to 400 mg), combined with azacitidine (75 mg/m²) on days 1–7 of each 28-day cycle. The primary endpoint was ORR (2006 IWG criteria); secondary endpoints included complete remission (CR), overall survival (OS), and AML progression. Results: Twenty-eight patients (median age: 63 years) were enrolled, with a median follow-up of 8.5 months. ORR was 85.7% per 2006 IWG (CR: 35.7%, marrow CR: 50.0%), and 78.6% per 2023 IWG (CR: 35.7%). Responses were consistent across molecular and IPSS-R subgroups. Median OS was not reached. High neutrophil count and high cytogenetic risk were favorable factors; TP53 mutation/deletion was an adverse prognostic marker. Grade 3–4 hematologic toxicities included neutropenia (96.4%), anemia (71.4%), and thrombocytopenia (64.3%). Serious adverse events (35.7%) were mainly infections. No dose-limiting or unexpected toxicities were observed. Conclusions: The 15-day venetoclax plus azacitidine regimen demonstrated high efficacy and manageable toxicity in treatment-naïve HR-MDS. It may be particularly beneficial for patients with high neutrophil counts, adverse cytogenetics, or those eligible for HSCT, supporting further investigation in larger trials. Full article

Background: The emergence of therapy-related myelodysplastic syndrome (t-MN) after autologous stem cell transplantation (ASCT) is well documented. However, with the growing use of chimeric antigen receptor (CAR) T-cell therapy for relapsed/refractory B-cell malignancies, concerns about secondary myeloid neoplasms, particularly MN, have arisen. The mechanisms and cytogenetic features associated with post-CAR-T MN, especially chromosome 7 abnormalities, remain underexplored. Objectives: To compare the incidence, timing, and cytogenetic characteristics of MN developing after CAR-T-cell therapy versus ASCT, and to evaluate the potential association between CAR-T therapy, persistent cytopenias, and these specific alterations. Study Design: This was a retrospective, single-center study of 275 patients with B-cell malignancies treated between 2015 and 2024 at Hospital Universitario Central de Asturias (Spain). Of these, 259 patients underwent ASCT and 16 received CAR-T-cell therapy (axicabtageneciloleucel n = 13, tisagenlecleucel n = 2, brexucabtageneautoleucel n = 1). Clinical, cytogenetic, and laboratory data were collected and analyzed. Incidence rates were compared using Fisher’s exact test, and time-to-event outcomes was evaluated using the Mann–Whitney U test (given the small number of events). Statistical significance was set at p < 0.05. Results: Myeloid neoplasms were diagnosed in 3 of 259 ASCT patients (1.15%) and in 2 of 16 CAR-T-cell patients (12.5%) (p = 0.03). The median time to myeloid neoplasm diagnosis was numerically shorter in the CAR-T group (15.5 vs. 69 months, p = 0.096). All post-CAR-T cases presented persistent cytopenias and cytokine release syndrome (CRS). Cytogenetic analyses revealed de novo monosomy 7 and 7q deletion in both CAR-T-related cases, whereas no chromosome 7 abnormalities were detected in ASCT-related cases. Pre-treatment samples did not show these abnormalities, although limitations in the sensitivity of the assays preclude the definitive exclusion of minor pre-existing clones. Both affected CAR-T patients had prolonged CAR-T cell persistence and required transfusional support due to hematologic toxicity. One patient was diagnosed with high-risk MN with 5q and 7q deletion and the other with Clonal Cytopenia of Uncertain Significance (CCUS) with monosomy 7. Conclusions: CAR-T-cell therapy was associated with a significantly higher and earlier incidence of myeloid neoplasms compared to ASCT in this cohort. The development of post-CAR-T myeloid neoplasm was characterized by persistent cytopenias, prolonged CAR-T cell persistence, and de novo chromosome 7 alterations. While the small sample size necessitates cautious interpretation, these findings may suggest a distinct pathogenesis potentially linked to inflammation, immune toxicity, or the expansion of pre-existing clones. This highlights the need for long-term hematologic monitoring and evaluation for clonal hematopoiesis prior to CAR-T-cell therapy, especially in heavily pretreated patients. Full article

Objectives: The aim of this study was to evaluate the stability of azacitidine (AZA) under clinical storage conditions (room temperature vs. refrigeration) to identify practical protocols that minimize waste and improve cost-effectiveness. Methods: AZA solutions (1 mg/mL) were stored at 23 ± 2 °C or 4 °C. Stability was assessed using a validated high-performance liquid chromatography (HPLC) method. Chromatographic separation was achieved on a Hypersil ODS C₁₈ column (250 mm × 4.6 mm, 5 μm) using an isocratic mobile phase of 50 mM potassium phosphate buffer (pH 7.0)-acetonitrile (98:2, v/v) at a flow rate of 1.0 mL/min, with UV detection at 245 nm and a 20 μL injection volume. The method demonstrated specificity for AZA and its main degradation product (DP), with LOD and LOQ of 12.56 μg/mL and 62.8 μg/mL, respectively. Linearity (R² = 0.9928), precision (RSD% < 5 for mid/high levels), and accuracy (mean recovery 96%) were established. Results: Azacitidine degraded rapidly at room temperature, with >85% loss within 24 h. In contrast, refrigeration at 4 °C significantly delayed degradation, with only ~26% loss observed over the same 24 h period. Chromatographic analysis confirmed the formation of a primary degradation product (tentatively identified as the open-ring hydrolytic species N-(formylamidino)-N′-β-D-ribofuranosylurea based on its chromatographic behavior and literature data), consistent with the known hydrolytic pathway. The applied HPLC-UV method offered an optimal balance of specificity and practicality for monitoring this main degradation trend under clinical storage conditions, distinguishing it from more complex techniques used primarily for structural elucidation. Conclusions: The pronounced instability of reconstituted AZA underscores the critical importance of strict adherence to immediate-use protocols. Refrigeration provides only a limited stability window. Based on our kinetic data, maintaining the reconstituted solution within an acceptable degradation limit (e.g., ≤10% loss) at 4 °C would require administration within a very short timeframe, supporting current handling guidelines to ensure therapeutic efficacy and minimize economic waste. Full article

Background: Myelodysplastic syndromes (MDSs) and acute myeloid leukemia (AML) are clonal hematological disorders that share molecular origins but present with distinct clinical features. MicroRNAs (miRNAs) are key post-transcriptional regulators, and their altered expression may reflect biological shifts contributing to disease progression. Methods: Expression levels of miR-155, miR-181, miR-221, miR-222, and miR-223 were analyzed by RT-qPCR in bone marrow samples from 37 MDS patients, 20 AML patients, and 7 controls. Group comparisons were performed using ANOVA (with Benjamini–Hochberg correction) and Tukey post hoc testing. Diagnostic performance and network behavior were evaluated using ROC analysis, Pearson correlation matrices, and principal component analysis (PCA). Results: miR-155, miR-181, and miR-223 were upregulated in AML, whereas miR-221 and miR-222 were downregulated. miR-222 showed the highest diagnostic accuracy (AUC ~0.87 for both AML vs. control and MDS vs. control). Its expression was significantly higher in high IPSS-R MDS cases (p = 0.046), with a similar upward tendency for miR-221 (p = 0.054). Progressive loss of coordinated miRNA expression was observed from controls to MDS and AML. PCA supported these findings by showing separation mainly driven by miR-222 and miR-155. Conclusions: Combined miRNA profiling highlights miR-222 and, to a lesser extent miR-155, as consistent indicators of myeloid disease transformation. While further validation in larger and genetically stratified cohorts is warranted, these findings support the potential contribution of miRNA signatures to diagnostic evaluation and risk stratification in MDS and AML, in line with precision hematology approaches. Full article

This review describes the dramatic transformation that has occurred in the last ten years in the therapeutic landscape for hematologic malignancies, such as leukemias, lymphomas, myelomas, and myelodysplastic syndromes. Treatment paradigms have quickly changed from depending solely on cytotoxic chemotherapy to embracing precision medicine, driven by a previously unprecedented understanding of disease biology and precise molecular changes. The development of powerful immunotherapies (such as CAR T-cell therapy and bispecific antibodies) and innovative targeted agents (like BTK inhibitors, BCL-2 inhibitors, and immunomodulatory medications) is at the heart of this revolution. In addition to evaluating new and synergistic combination strategies, this paper examines the clinical utility, efficacy, and recent developments of these novel agents. It also addresses important issues like managing acquired drug resistance, minimizing financial burden, and adapting clinical trial designs to keep pace with innovation. These advancements are collectively redefining clinical practice, leading to deeper and more durable responses, and significantly improving the prognosis and quality of life for patients. Full article

Background: Myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML) are clonal stem cell disorders in which disrupted post-transcriptional regulation contributes to aberrant hematopoiesis and leukemic transformation. The miRNA biogenesis machinery, which comprises Drosha, DGCR8, Dicer, TARBP2, and AGO1, ensures the precise maturation of miRNAs that control lineage commitment and proliferation. However, the extent to which alterations in this pathway reshape hematopoietic gene networks during myeloid disease evolution remains largely unexplored. Methods: Bone marrow samples from newly diagnosed, untreated MDS and AML patients and matched healthy controls were analyzed for the expression of five key miRNA biogenesis genes using quantitative real-time PCR. Statistical comparisons, correlation matrices, and ROC analyses were performed to characterize gene-expression differences. These results were integrated with multigene logistic modeling, decision-curve analysis, and exploratory random forest/SHAP approaches to evaluate molecular interactions and diagnostic relevance. Results: DROSHA, DICER1, and TARBP2 were significantly downregulated in both MDS and AML, suggesting impaired miRNA maturation and a loss of global post-transcriptional control. DGCR8 expression increased across higher-risk MDS groups, suggesting compensatory activation of the Microprocessor complex, whereas AGO1 levels remained relatively stable, consistent with partial maintenance of RISC function. Correlation analyses revealed a co-regulated DROSHA–TARBP2–AGO1 module. ROC, logistic, and machine learning models identified DGCR8 and DICER1 as the strongest diagnostic discriminators. The integrated five-gene signature achieved high discriminative performance (AUC ≈ 0.98) and showed promise but remains preliminary potential for clinical application. Conclusions: Our findings suggest that defects in miRNA biogenesis disrupt hematopoietic homeostasis, reflecting common mechanisms in MDS and AML. The dysregulation of DICER1, DGCR8, and TARBP2 offers insights into miRNA-driven leukemogenesis and may pave the way for miRNA-based diagnostic and therapeutic strategies, pending validation in larger cohorts. Although transcript-level data are provided, future studies should include functional validation to determine the impact on downstream miRNA processing and hematopoietic pathways. Full article

Acute myeloid leukemia (AML) and myelodysplastic neoplasms (MDS) are clonal hematopoietic malignancies in which next-generation sequencing (NGS) has become integral for diagnosis, classification, risk stratification, and measurable residual disease (MRD) monitoring. Traditional cytogenetic and PCR-based assays remain useful, but targeted NGS panels now represent the standard of care, providing rapid and sensitive detection of recurrent gene mutations, structural variants, and gene fusions. Whole-genome, whole-exome, and RNA sequencing and long-read platforms expand the spectrum of detectable alterations, though targeted panels remain most practical for routine diagnostics. Bioinformatic pipelines and quality metrics—including read length, sequencing depth, and coverage—are critical for accurate variant calling, with validation often required for variants of uncertain significance or those near detection thresholds. NGS is now embedded in diagnostic frameworks, including the WHO 2022 and ICC classifications, which incorporate recurrently mutated genes such as TP53, ASXL1, RUNX1, and FLT3. These data inform prognostic models, with ELN-2022 defining adverse-risk AML subgroups for patients treated with intensive chemotherapy, ELN-2024 AML for patients treated with less-intensive therapies, and the IPSS-M refining MDS risk categories by integrating mutational data. NGS also enables MRD monitoring, with gene panels and PCR-NGS hybrid approaches (e.g., for FLT3-ITD) showing increasing clinical utility, though standardization is still lacking. Furthermore, diagnostic NGS frequently uncovers germline predisposition syndromes (e.g., DDX41, GATA2), with significant implications for treatment decisions and donor selection in transplantation. In this manuscript, we review the advantages, limitations, and future perspectives of NGS in the clinical management of AML and MDS with a particular emphasis on the biological and technical principles underlying its use in these diseases. Furthermore, we discuss how NGS findings may influence diagnosis, prognostic classification, and therapeutic decision-making within current clinical frameworks. Our aim is to provide a comprehensive overview of NGS fundamentals to support clinicians in navigating the increasing complexity of molecular data in daily practice. Full article

Background/Objectives: Genetic abnormalities are critical for the diagnosis, prognosis, and therapeutic management of myelodysplastic syndromes (MDS). This study aims to evaluate the clinical utility of Multiplex Ligation-dependent Probe Amplification (MLPA) as a rapid and cost-effective method, determining its place alongside Next-Generation Sequencing (NGS) for the initial genetic assessment of patients with MDS. Methods: Bone marrow samples from 68 patients newly diagnosed with MDS were analyzed. Genomic DNA was investigated using the SALSA MLPA P414-C1 MDS probe mix to detect common copy number variations (CNVs). Results: MLPA detected genetic variants in 25 patients (36.8%). The most common finding was a single chromosomal abnormality (26.5%). Multiple pathological findings were observed in only 1.5% of patients, and a JAK2 mutation was observed in 8.8% of the cohort. However, the presence of these aberrations did not show a statistically significant association with overall survival (OS) in the cohort. Patient sex was identified as the only variable that was associated with a marginal level of statistical significance regarding OS, indicating a worse prognosis for males. Conclusions: MLPA is a valuable, rapid, and cost-effective tool for initial genetic screening in low-resource settings. This was highlighted by our finding that sex was the sole significant prognostic factor, while the MLPA-detected variants were not found to be significant. The findings suggest that comprehensive risk stratification aligned with international standards requires more advanced molecular technologies. Full article

The only cytogenetic alteration defining a subtype of a myelodysplastic syndrome is represented by the deletion of the long arm of chromosome 5 (del(5q)), now classified as MDS with isolated del(5q). This subtype is associated with a peculiar phenotype mainly dependent on the haploinsufficiency of several genes located on the deleted arm of chromosome 5. These patients show a good prognosis and respond to treatment with lenalidomide, but some cases progress to acute myeloid leukemia. Molecular studies have, in part, elucidated the heterogeneity of MDS with isolated del(5q), mainly related to the association with different co-mutations that may affect leukemic transformation and survival. In other MDS patients, del(5q) is combined with other chromosomal abnormalities, giving rise to a condition of complex karyotype, associated with frequent TP53 mutations and with a poor prognosis. Two different molecular pathways seem to be responsible for the generation of MDS with isolated del(5q) or of MDS with del(5q) associated with a complex karyotype. Full article

Background/Objectives: Pediatric myelodysplastic syndrome (pMDS) is a rare, heterogeneous, clonal hematopoietic stem cell disease with a risk of evolution to acute myeloid leukemia (AML). Clonal cytogenetic abnormalities are present in 30–60% of pMDS. However, unlike in adults, the prognostic significance of chromosomal alterations, particularly their role in predicting evolution to AML, remains limited in pMDS. To acknowledge this gap, we studied the cytogenetic abnormalities in pMDS and analyzed their associations with subtypes and evolution to AML. Furthermore, in the Discussion Section, we pointed out key genes involved in these chromosomal alterations. Methods: Cytogenetic analysis was performed on 193 pediatric patients using G-banding and fluorescence in situ hybridization. Results: Abnormal karyotypes were observed in 43.5% (84/193) of patients, mainly in the advanced subtype. The main chromosomal alterations were monosomy 7 (−7) in 14% of the cases (12/84), deletion of the long arm of chromosome 11 [del(11q)] in 12% (10/84) and both trisomy 8 (+8) and deletion of the long arm of chromosome 7 [del(7q)] in 8% (7/84). Evolution from MDS to AML was observed in 22% of the patients (42/193), and it was associated with complex karyotypes, del(11q), −7/del(7q), and +8. Conclusions: Our results suggest that specific chromosomal alterations, such as del(11q), del(7q), and +8, may predict evolution to AML and might be considered high-risk cytogenetic markers in pMDS. Full article