[Allogeneic transplantation as a therapeutic option for atypical chronic myeloid leukemia].

Atypical chronic myeloid leukemia (aCML) is a rare disease classified as a myelodysplastic/myeloproliferative neoplasm (MDS/MPN). Recent advances in gene mutational profiling have clarified the characteristics of aCML as a disease entity relative to other MDS/MPNs. Although some studies suggest the efficacy of DNA demethylating agents and tyrosine kinase inhibitors, data about these agents are limited due to the small number of patients. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is only therapeutic option that can provide durable remission for aCML and other MDS/MPNs. Retrospective studies from Europe and Japan revealed the clinical results of allo-HSCT for aCML. This review summarizes the pathogenesis of aCML and the development of allo-HSCT and other therapeutic options.

Hepatoid thymic carcinoma in a polycythemia vera patient treated with ropeginterferon Alfa-2b: Clinical, histopathological and molecular correlates.

Hepatoid thymic carcinoma (HTC) is an extremely rare variant of primary epithelial tumor of the thymus morphologically resembling hepatocellular carcinoma Herein, we report an additional case of HTC diagnosed in a 40-years-old man affected by polycythemia vera and treated with ropeginterferon alfa 2-b, for the first time deeply analyzing the molecular profile of this distinctive thymic malignancy. By immunohistochemistry, tumor cells were positive for cytokeratin 7-19, GLUT1, and Hep-Par-1, whereas AFP tested negative. Whole exome sequencing revealed loss of function mutations in TP53, STK11, PBRM1, SMAD3, FN1, NTRK1, and FANCD2, as well as gain of function mutations in MTOR, BCL11A and COL1A1, along with amplification of CCND3 and MDM2. This mutational landscape halfway between thymic carcinoma (TP53, PBRM1) and hepatoid variant carcinoma of other sites (STK11) suggests that, at some point during carcinogenesis, a switch occurred from an epithelial thymic phenotype to a hepatoid-like one.

Landscape of biallelic DNMT3A mutant myeloid neoplasms.

DNA methyltransferase 3 A mutations (DNMT3AMT) are frequent in myeloid neoplasia (MN) and mostly heterozygous. However, cases with multiple DNMT3AMT can be also encountered but their clinical and genetic landscape remains unexplored. We retrospectively analyzed 533 cases with DNMT3AMT identified out of 5,603 consecutive MNs, of whom 8.4% had multiple DNMT3AMT hits. They were most frequent in acute myeloid leukemia (AML) with R882 variant accounting for 13.3% of the multi-hits. Multiple DNMT3AMT more likely coincided with IDH2 (P = 0.005) and ETV6 (P = 0.044) mutations compared to patients with single DNMT3AMT. When the sum of variant allele frequencies (VAFs) for multiple DNMT3AMT exceeded 60%, we found a significant positive clonal burden correlation of the two DNMT3A variants (P < 0.0001) suggesting that they occurred in biallelic configuration. AML patients with biallelic DNMT3A inactivation (n = 52) presented with older age (P = 0.029), higher leukocytes (P < 0.0001) and peripheral blast counts (P = 0.0001) and significantly poorer survival rate (5.6% vs. 47.6% at 2 years; P = 0.002) than monoallelic DNMT3AMT. Multivariate analysis identified biallelic DNMT3AMT (HR 2.65; P = 0.001), male gender (HR 2.05; P = 0.014) and adverse genetic alteration according to the European LeukemiaNet 2022 classification (HR 1.84; P = 0.028) as independent adverse factors for survival, whereas intensive chemotherapy (HR 0.47; P = 0.011) favorably influenced outcomes. Longitudinal molecular analysis of 12 cases with biallelic DNMT3AMT demonstrated that such clones persisted or expanded in 9 relapsed or transformed cases (75%) suggesting the early origin of biallelic hits with strong leukemogenic potential. Our study describes the likelihood that biallelic DNMT3AMT, while rare, are indeed compatible with clonal expansion and thus questions the applicability of synthetic lethality strategies.

The Role of Mutated Calreticulin in the Pathogenesis of BCR-ABL1-Negative Myeloproliferative Neoplasms.

Myeloproliferative neoplasms (MPNs) are characterized by increased proliferation of myeloid lineages in the bone marrow. Calreticulin (CALR) 52 bp deletion and CALR 5 bp insertion have been identified in essential thrombocythemia (ET) and primary myelofibrosis (PMF). There is not much data on the crosstalk between mutated CALR and MPN-related signaling pathways, such as JAK/STAT, PI3K/Akt/mTOR, and Hedgehog. Calreticulin, a multifunctional protein, takes part in many cellular processes. Nevertheless, there is little data on how mutated CALR affects the oxidative stress response and oxidative stress-induced DNA damage, apoptosis, and cell cycle progression. We aimed to investigate the role of the CALR 52 bp deletion and 5 bp insertion in the pathogenesis of MPN, including signaling pathway activation and functional analysis in CALR-mutated cells. Our data indicate that the JAK/STAT and PI3K/Akt/mTOR pathways are activated in CALR-mutated cells, and this activation does not necessarily depend on the CALR and MPL interaction. Moreover, it was found that CALR mutations impair calreticulin function, leading to reduced responses to oxidative stress and DNA damage. It was revealed that the accumulation of G2/M-CALR-mutated cells indicates that oxidative stress-induced DNA damage is difficult to repair. Taken together, this study contributes to a deeper understanding of the specific molecular mechanisms underlying CALR-mutated MPNs.

Myeloproliferative Neoplasms and Cardiovascular Disease: A Review.

OPINION STATEMENT: Myeloproliferative neoplasms (MPN) are a heterogenous group of disorders of clonal hematopoiesis characterized by constitutive activation of the JAK/STAT signaling pathway leading to proliferation of blood cells. Cardiovascular disease (CVD) contributes significantly to the morbidity and mortality of patients with MPN. Particularly well-known CVD complications of MPNs are arterial and venous thrombotic events. However, MPNs are also associated with other forms of CVD including atrial fibrillation, heart failure, and pulmonary hypertension. Recent studies have characterized outcomes of patients with MPN and CVD, including acute myocardial infarction (AMI), heart failure, atrial fibrillation, and pulmonary hypertension. Additionally, optimal cardiovascular disease prevention strategies in patients with MPN are not yet clear. Further investigation is warranted to improve CVD outcomes in patients with MPN. Clinicians should be aware of cardiovascular complications of MPN, including thrombotic as well as non-thrombotic complications (heart failure, arrhythmias, pulmonary hypertension).

The Role of Direct Oral Anticoagulants in Managing Myeloproliferative Neoplasms Patients.

Purpose: Thrombosis and bleeding significantly affect morbidity and mortality in myeloproliferative neoplasms (MPNs). The efficacy and safety of direct oral anticoagulants (DOACs) in MPN patients remain uncertain. Materials and Methods: We conducted a large, retrospective, nationwide cohort study using the Korean Health Insurance Review and Assessment Service database from 2010 to 2021. Results: Out of the 368 MPN patients included in the final analysis, 62.8% were treated with DOACs for atrial fibrillation (AF), and 37.2% for venous thromboembolism (VTE). The AF group was statistically older with higher CHA2DS2-VASc scores compared to the VTE group. Antiplatelet agents were used in 51.1% of cases, and cytoreductive drugs in 79.3%, with hydroxyurea being the most common (64.9%). The median follow-up was 22.3 months, with one-year cumulative incidence rates of thrombosis and bleeding at 11.1% and 3.7%, respectively. Multivariate analysis identified CHA2DS2-VASc scores ≥ 3 (HR=3.48), concomitant antiplatelet use (HR = 2.57), and cytoreduction (HR=2.20) as significant thrombosis risk factors but found no significant predictors for major bleeding. Conclusion: Despite the limitations of retrospective data, DOAC treatment in MPN patients seems effective and has an acceptable bleeding risk.

The survivin/XIAP suppressant YM155 impairs clonal growth and induces apoptosis in JAK2V617F cells.

The central role of the control of apoptosis in the pathophysiology of Philadelphia chromosome-negative myeloproliferative neoplasms has recently been reinforced in genetic and pharmacological studies. The inhibitor of apoptosis protein family has eight members and plays an important role in apoptosis, with the most studied being survivin (BIRC5) and X-linked inhibitor of apoptosis (XIAP). YM155 is a small molecule with antineoplastic potential that has been described as a suppressant of survivin and XIAP. In the present study, BIRC5 expression was significantly increased in primary myelofibrosis patients compared to healthy donors. On the other hand, XIAP expression was reduced in myeloproliferative neoplasms patients. In JAK2V617F cells, YM155 reduces cell viability and autonomous clonal growth and induces apoptosis, cell cycle arrest, and autophagy. HEL cells that show greater malignancy are more sensitive to the drug than SET2 cells. In the molecular scenario, YM155 modulates apoptosis-, cell cycle-, DNA damage- and autophagy-related genes. Protein expression analysis corroborates the observed cellular phenotype and exploratory gene expression findings. In summary, our results indicate that survivin/BIRC5 and XIAP are differently expressed in myeloproliferative neoplasms and YM155 has multiple antineoplastic effects on JAK2V617F cells suggesting that inhibitor of apoptosis proteins may be a target for pharmacological interventions in the treatment of these diseases.

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratio as novel prognostic biomarkers in BCR-ABL negative myeloproliferative neoplasms.

Higher neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) have been associated with increased risk of thrombosis, cardiovascular mortality, but their role in myeloproliferative neoplasms (MPN) remains unclear. We analyzed NLR and PLR as prognostic markers for thrombosis and overall survival (OS) in the study that included 461 consecutive MPN patients who were diagnosed from 2018 to 2022 at University center. Twenty age-matched patients without hematological disorder were used as controls. NLR and PLR were significantly increased in whole MPN group compared to controls. NLR was highest in PV > PMF > ET (p < 0.001) while PLR was highest in ET > PMF > PV (p < 0.001). Thrombosis occurrence during follow-up correlated with NLR, NLR ≥ 4.5, presence of ≥ 2 CV factors and previous thrombosis. Arterial thrombosis was associated with previous thrombosis, NLR and NLR ≥ 4.5. Similarly in venous thrombosis previous thrombosis was risk factor, together with NLR, NLR ≥ 4.5, PLR, but also secondary malignancy and female gender. In multivariate Cox model, most important factors for thrombosis development during follow-up were previous thrombosis, NLR ≥ 4.5 and PLR ≥ 500; for arterial thrombosis, NLR ≥ 4.5 and previous thrombosis; for venous thrombosis PLR ≥ 500 and previous thrombosis. Patients with pre-PMF had significantly higher NLR than ET patients. In multivariate Cox regression model, most important factors associated with survival were NLR ≥ 4.5 and PLR ≥ 500. This study highlights strong prognostic correlation of NLR ≥ 4.5 and PLR ≥ 500 with development of thrombosis and OS in MPN. Besides previous thrombosis, most important factor associated with development of arterial thrombosis is NLR ≥ 4.5 and for venous PLR ≥ 500. Our results revealed that NLR ≥ 4.5 could be used as additional marker to distinguish ET from prePMF.

[Budd-Chiari syndrome and JAK2 gene mutation].

Budd-Chiari syndrome (BCS) is a rare vascular disorder characterized by obstruction of hepatic venous outflow, culminating in elevated hepatic and portal venous pressure. BCS is associated with myeloproliferative neoplasms (MPN) in 40% of cases, which is significantly higher than the rate observed in other venous thrombotic conditions, and suggests that MPN may contribute to the etiology of BCS. In particular, the JAK2 V617F mutation has recently attracted substantial attention, given its profound association with thrombogenesis, mechanically implicated through endothelial damage, increased blood cell adhesion, and facilitation of neutrophil extracellular trap formation. A common treatment approach consists of anticoagulation for prevention and treatment of thrombosis, and cytoreductive therapy targeting MPN. However, as no definitive evidence exists for this approach, a bespoke therapeutic strategy tailored to individual patient profiles is required.

Applications of artificial intelligence to myeloproliferative neoplasms: a narrative review.

INTRODUCTION: Artificial intelligence (AI) is a rapidly growing field of computational research with the potential to extract nuanced biomarkers for the prediction of outcomes of interest. AI implementations for the prediction for clinical outcomes for myeloproliferative neoplasms (MPNs) are currently under investigation. AREAS COVERED: In this narrative review, we discuss AI investigations for the improvement of MPN clinical care utilizing either clinically available data or experimental laboratory findings. Abstracts and manuscripts were identified upon querying PubMed and the American Society of Hematology conference between 2000 and 2023. Overall, multidisciplinary researchers have developed AI methods in MPNs attempting to improve diagnostic accuracy, risk prediction, therapy selection, or pre-clinical investigations to identify candidate molecules as novel therapeutic agents. EXPERT OPINION: It is our expert opinion that AI methods in MPN care and hematology will continue to grow with increasing clinical utility. We believe that AI models will assist healthcare workers as clinical decision support tools if appropriately developed with AI-specific regulatory guidelines. Though the reported findings in this review are early investigations for AI in MPNs, the collective work developed by the research community provides a promising framework for improving decision-making in the future of MPN clinical care.

No impact of steatotic liver disease on clinical outcomes in patients with essential thrombocythemia and polycythemia vera: A pilot study.

The presence of steatotic liver disease (SLD) is associated with an increased cardiovascular risk in the general population. Chronic myeloproliferative neoplasms (MPNs), essential thrombocythemia (ET) and polycythemia vera (PV), are characterized by clonal myeloproliferation, chronic inflammatory state, and increased cardiovascular morbidity and mortality. The aim of this single-center study was to analyze clinical associations and the potential prognostic impact of SLD in ET and PV patients. We retrospectively included 108 patients (64 ET and 44 PV); median age was 70.5 years (range 21-92), 68 (63 %) were females, and the median follow-up time was 69 months. Baseline SLD presence was defined ultrasonographically and was detected in 25 (23.1 %) patients. There were no associations of SLD with any of the clinical and laboratory patient characterictics. Also, baseline ultrasonographic presence of SLD did not have an impact on future thrombotic, bleeding and disease transformation risk, nor patient survival. None of the patients experienced signs of liver failure during the follow-up. In conclusion, the presence of SLD in ET and PV patients does not seem to have major clinical implications. Therefore, patients may be advised about the generally harmless nature of SLD when occurring in the MPN context.

Myeloproliferative neoplasms: young patients, current data and future considerations.

The Philadelphia-negative chronic myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders predominantly occurring in elderly, whereas in children and young adults are quite infrequent. Therefore, less is known about clinical presentation, genetic abnormalities, prognosis and best management strategies for this groups of patients. Currently, more cases of younger MPN patients are diagnosed. Nevertheless, diagnosis of MPNs, especially in childhood, may be difficult due to lower incidence of JAK2V617F and CALR mutations and differences in peripheral blood counts between adults and children. Challenges for younger MPN patients are longer life expectances, specific psychosocial need, fertility and pregnancy need and a long term therapy side effect (including second cancers). The most severe MPNs complication is transformation to secondary myelofibrosis (MF) or acute myeloid leukemia (AML). Optimal management of young MPNs remains a challenge as the classical risk scores fail in young MPNs. Moreover, the main objective of young MPNs therapy should be the disease outcome modification. Therefore, international collaborative work between pediatricians and "adult hematologists" is required to measure outcomes and generate protocol of management of young MPNs.

Combination of ligand­based and structure­based virtual screening for the discovery of novel Janus kinase 2 inhibitors against philadelphia-negative myeloproliferative neoplasms.

The activating V617F mutation in Janus kinase 2 (JAK2) has been shown to be the major cause for classic Philadelphia-negative myeloproliferative neoplasms (MPNs). Thus, the development of pharmacologic JAK2 inhibitors is an essential move in combating MPNs. In this study, screening methods examining both ligands and their structures were developed to discover novel JAK2 inhibitors from the ChemDiv database with virtual screening identifying 886 candidate inhibitors. Next, these compounds were further filtered using ADMET, drug likeliness, and PAINS filtering, which reduced the compound number even further. This consolidated list of candidate compounds (n = 49) was then evaluated biologically at molecular level and the highest performing inhibitor with a novel scaffold was selected for further examination. This candidate inhibitor, CD4, was then subjected to molecular dynamics studies, with complex stability, root-mean-square deviation, radius of gyration, binding free energy, and binding properties all examined. The result suggested that CD4 interacts with JAK2 and that the CD4-JAK2 complex is stable. This study was able to identify a candidate inhibitor that warrants further examination and optimization and may potentially serve as a future MPN treatment.

Mechanobiology and Primary Cilium in the Pathophysiology of Bone Marrow Myeloproliferative Diseases.

Philadelphia-Negative Myeloproliferative neoplasms (MPNs) are a diverse group of blood cancers leading to excessive production of mature blood cells. These chronic diseases, including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), can significantly impact patient quality of life and are still incurable in the vast majority of the cases. This review examines the mechanobiology within a bone marrow niche, emphasizing the role of mechanical cues and the primary cilium in the pathophysiology of MPNs. It discusses the influence of extracellular matrix components, cell-cell and cell-matrix interactions, and mechanosensitive structures on hematopoietic stem cell (HSC) behavior and disease progression. Additionally, the potential implications of the primary cilium as a chemo- and mechanosensory organelle in bone marrow cells are explored, highlighting its involvement in signaling pathways crucial for hematopoietic regulation. This review proposes future research directions to better understand the dysregulated bone marrow niche in MPNs and to identify novel therapeutic targets.

C-Mannosyl tryptophan is a novel biomarker for thrombocytosis of myeloproliferative neoplasms.

C-Mannosyl tryptophan (CMW), a unique glycosylated amino acid, is considered to be produced by degradation of C-mannosylated proteins in living organism. Although protein C-mannosylation is involved in the folding and secretion of substrate proteins, the pathophysiological function in the hematological system is still unclear. This study aimed to assess CMW in the human hematological disorders. The serum CMW levels of 94 healthy Japanese workers were quantified using hydrophilic interaction liquid chromatography. Platelet count was positively correlated with serum CMW levels. The clinical significance of CMW in thrombocytosis of myeloproliferative neoplasms (T-MPN) including essential thrombocythemia (ET) were investigated. The serum CMW levels of the 34 patients with T-MPN who presented with thrombocytosis were significantly higher than those of the 52 patients with control who had other hematological disorders. In patients with T-MPN, serum CMW levels were inversely correlated with anemia, which was related to myelofibrosis (MF). Bone marrow biopsy samples were obtained from 18 patients with ET, and serum CMW levels were simultaneously measured. Twelve patients with bone marrow fibrosis had significantly higher CMW levels than 6 patients without bone marrow fibrosis. Collectively, these results suggested that CMW could be a novel biomarker to predict MF progression in T-MPN.

Epidemiology and disease characteristics of myelofibrosis: a comparative analysis between Italy and global perspectives.

Myelofibrosis (MF) is a clonal disorder of hematopoietic stem cells characterized by altered bone marrow function and fibrosis. The aim of this narrative review is to report on the most recent epidemiologic data and to discuss features of MF and current strategies for the management of this condition in clinical practice. MF features covered by our review will include: characteristics of patients with MF; myeloproliferative and myelodepletive phenotypes; MF-associated thrombosis and bleeding; risk of infections; prefibrotic and overt PMF; secondary MF. Finally, we will discuss a few aspects of MF management in clinical practice and suggest strategies for its optimization and standardization. The focus of our paper is on Italy, but relevant data from other countries will also be reviewed.

Systemic Inflammatory Index in Polycythemia Vera and Its Prognostic Implications.

Background: This study aimed to evaluate the clinical and prognostic associations of the systemic inflammatory index (SII) in polycythemia vera (PV) patients. SII integrates information on absolute neutrophil (ANC), lymphocyte (ALC), and platelet counts into one index (calculated as ANCxALC/platelet count) and was previously shown to predict thrombotic and mortality risks in the general population. Methods: A total of 279 PV patients treated in several hematologic centers in Croatia and Serbia was retrospectively evaluated. Results: The median SII for the overall cohort was 1960. Higher SII stratified at the specific cut-off points was significantly associated with shorter time to thrombosis (TTT; p = 0.004) driven by arterial thrombotic events, and shorter overall survival (OS; p < 0.001). Higher SII was able to refine the European Leukemia Net-defined high-risk patient subgroup for both thrombotic and survival risks, especially in individuals over 60 years of age. SII and all other evaluated CBC components and indices (leukocytes, ANC, ALC, platelets, neutrophil to lymphocyte ratio (NLR), and platelet to lymphocyte ratio (PLR)) demonstrated low-to-modest prognostic properties, whereas SII outperformed other parameters with respect to TTT and OS prognostications. Discussion: The presented results complement prior studies evaluating the prognostic performance of different CBC components for thrombotic and survival risk predictions and offer more options to personalize PV treatments.

Cytogenetics and genomics in CML and other myeloproliferative neoplasms.

Chronic myeloid leukemia is defined by the presence of the Philadelphia translocation t (9; 22) resulting in the BCR::ABL1 fusion. The other myeloproliferative neoplasms (MPN) subtypes also carry typical chromosomal abnormalities, which however are not pathognomonic for a specific entity of MPN. According to the WHO classification the distinction between these entities is still based on the integration of cytological, histopathological and molecular findings. Progression of CML into accelerated and blastic phase is usually driven by additional chromosome abnormalities and ABL1 kinase mutations. In the other MPN subtypes the additional mutations besides driver gene mutations in JAK2, MPL and CALR have a decisive impact on the propensity for progression. In addition, the sequence in which the driver mutations and risk conveying additional mutations have been acquired appears to play an important role. Here, we review cytogenetic and molecular changes in CML and MPN that should be evaluated during diagnosis and disease monitoring.