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Motivation: By accounting for variants within measured transcripts, it is possible to evaluate the status of somatic variants using single-cell RNA-sequencing (scRNA-seq) and to characterize their clonality. However, the sparsity (very few reads per transcript) or bias in protocols (favoring 3' ends of the transcripts) makes the chance of capturing somatic variants very unlikely. This can be overcome by targeted sequencing or the use of mitochondrial variants as natural barcodes for clone identification. Currently, available computational tools focus on genotyping, but do not provide functionality for combined analysis of somatic and mitochondrial variants and functional analysis such as characterization of gene expression changes in detected clones. Results: Here, we propose SIGURD (SI ngle cell level G enotyping U sing sc R na D ata) (SIGURD), which is an R-based pipeline for the clonal analysis of scRNA-seq data. This allows the quantification of clones by leveraging both somatic and mitochondrial variants. SIGURD also allows for functional analysis after clonal detection: association of clones with cell populations, detection of differentially expressed genes across clones, and association of somatic and mitochondrial variants. Here, we demonstrate the power of SIGURD by analyzing single-cell data of colony-forming cells derived from patients with myeloproliferative neoplasms. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by excessive proliferation of myeloid cells. The COVID-19 pandemic has raised concerns regarding the impact of SARS-CoV-2 on patients with malignancies, particularly those with CML. This study aimed to investigate the effects of SARS-CoV-2 proteins on CML cell viability and the protective role of vitamin K2 (VK2) in conjunction with imatinib. Experiments conducted on K562 CML cells demonstrated that the SARS-CoV-2 envelope protein induces cytotoxicity and activates caspase 3/7, which are key markers of apoptosis. VK2 mitigated these cytotoxic effects and decreased cytokine production while inhibiting colony formation. Furthermore, the combination of VK2 with imatinib significantly reduced cellular proliferation, diminished mitochondrial membrane potential, and markedly suppressed colony formation. These findings suggest that VK2 protects CML cells from SARS-CoV-2-induced cytotoxicity and enhances the therapeutic efficacy of imatinib, presenting a potential strategy to improve CML treatment during the COVID-19 pandemic. [ABSTRACT FROM AUTHOR]

In previous research, we created a C. elegans model with homozygous mutations in calreticulin similar to those found in patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF), two myeloproliferative neoplasms (MPNs). This model, lacking JAK orthologs, enabled us to examine the transcriptomic effects caused by mutant calreticulin without the influence of JAK/STAT activation, the primary pathogenic mechanism associated with calreticulin mutations known to date. Most of the gene expression changes observed seemed to be due to a partial loss of protein function, with the alteration of the extracellular matrix being particularly notable. In this study, our aim was to determine whether this model exhibited any phenotype related to these transcriptomic alterations. The results demonstrate that these strains exhibit multiple phenotypes related to the alteration of the extracellular matrix, fat levels, and fertility, which could be a possible consequence of a partial loss of calreticulin function. These phenotypes resemble some of the clinical and molecular characteristics described in patients with MPNs, but they had never before been linked to a loss of protein function in humans. Thus, these results collectively suggest that CALR mutations could have significant effects on MPNs due to loss of protein function. Delving deeper into these effects to develop innovative therapies for these patients offers considerable potential and interest, given that targeted therapies for these patients have not yielded very promising results so far. [ABSTRACT FROM AUTHOR]

This viewpoint summarizes findings from analyses of large personal patient databases of myeloproliferative neoplasms (MPNs) to assess the impact of thrombosis on mortality, disease progression, and second cancers (SC). Despite advances, the current incidence of arterial and venous thrombosis remains a challenge. These events appear to signal a more aggressive disease course, as evidenced by their association with myelofibrosis progression and mortality using multistate models and time-dependent multivariable analysis. Inflammatory biomarkers, such as the neutrophil-to-lymphocyte ratio (NLR), are associated with the aggressiveness of polycythemia vera (PV) and essential thrombocythemia (ET), linking thrombosis to SC risk. This suggests a common inflammatory pathway likely influencing cardiovascular disease and cancer incidence. Notably, this is observed more frequently in younger patients, likely due to prolonged exposure to MPN and environmental inflammatory triggers. These data underscore the need for new studies to validate these associations, delineate the sequence of events, and identify therapeutic targets to mitigate thrombotic events and potentially improve overall patient outcomes in MPN. [ABSTRACT FROM AUTHOR]

Down syndrome (DS) is defined by an extra copy of chromosome 21 and confers an increased susceptibility to hematological disorders. Transient abnormal myelopoiesis (TAM) and myeloid‐leukemia associated with Down syndrome (ML‐DS) are two conditions that need to be accurately diagnosed to provide appropriate management. Both TAM and ML‐DS are characterized by proliferation of megakaryoblasts carrying a mutation in the GATA1 gene. Here, we report four cases with educational significance, highlighting typical diagnostic features that facilitate the differentiation between these two conditions, thereby assisting clinicians and medical laboratory professionals in effectively managing and monitoring these patients. [ABSTRACT FROM AUTHOR]

Myelofibrosis (MF) is a complex myeloproliferative neoplasm characterized by abnormal hematopoietic stem cell proliferation and subsequent bone marrow (BM) fibrosis. First documented in the late 19th century, MF has since been extensively studied to unravel its pathophysiology, clinical phenotypes, and therapeutic interventions. MF can be classified into primary and secondary forms, both driven by mutations in genes such as JAK2, CALR, and MPL, which activate the JAK-STAT signaling pathway. These driver mutations are frequently accompanied by additional non-driver mutations in genes like TET2, SRSF2, and TP53, contributing to disease complexity. The BM microenvironment, consisting of stromal cells, extracellular matrix, and cytokines such as TGF-β and TNF-α, plays a critical role in fibrosis and aberrant hematopoiesis. Clinically, MF manifests with symptoms ranging from anemia, splenomegaly, and fatigue to severe complications such as leukemic transformation. Splenomegaly, caused by extramedullary hematopoiesis, leads to abdominal discomfort and early satiety. Current therapeutic strategies include JAK inhibitors like Ruxolitinib, which target the JAK-STAT pathway, alongside supportive treatments such as blood transfusions, erythropoiesis-stimulating agents and developing combinatorial approaches. Allogeneic hematopoietic stem cell transplantation remains the only curative option, though it is limited to younger, high-risk patients. Recently approved JAK inhibitors, including Fedratinib, Pacritinib, and Momelotinib, have expanded the therapeutic landscape. Spatially Resolved Transcriptomics (SRT) has revolutionized the study of gene expression within the spatial context of tissues, providing unprecedented insights into cellular heterogeneity, spatial gene regulation, and microenvironmental interactions, including stromal-hematopoietic dynamics. SRT enables high-resolution mapping of gene expression in the BM and spleen, revealing molecular signatures, spatial heterogeneity, and pathological niches that drive disease progression. These technologies elucidate the role of the spleen in MF, highlighting its transformation into a site of abnormal hematopoietic activity, fibrotic changes, and immune cell infiltration, functioning as a "tumor surrogate." By profiling diverse cell populations and molecular alterations within the BM and spleen, SRT facilitates a deeper understanding of MF pathophysiology, helping identify novel therapeutic targets and biomarkers. Ultimately, integrating spatial transcriptomics into MF research promises to enhance diagnostic precision and therapeutic innovation, addressing the multifaceted challenges of this disease. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasm in which all the patients has the translocation (9;22) that generates de BCR::ABL1 tyrosine kinase. Despite this disease possessing a good biomarker (BCR::ABL1 transcripts level) for diagnosis and prognosis, many studies has been performed to investigate other molecules, such as the long noncoding RNAs (lncRNAs) and mRNAs, as potential biomarkers with the aim of predicting a change in BCR::ABL1 levels and as an associated biomarker. A RNAseq was performed comparing 6 CML patients with high BCR::ABL1 expression with 6 healthy control individuals, comprising the investigation cohort to investigate these molecules. To validate the results obtained by RNAseq, samples of 87 CML patients and 42 healthy controls were used in the validation cohort by RT-qPCR assays. The results showed lower expression of HOTAIR and PTGS2 in CML patients. The HOTAIR expression is inversely associated with BCR::ABL1 expression in imatinib-treated CML patients, and to PTGS2 showing that CML patients with high BCR::ABL1 expression showed reduced PTGS2 expression. [ABSTRACT FROM AUTHOR]

Background: Essential thrombocythemia (ET) is a myeloproliferative neoplasm characterized by uninhibited platelet production. It can present with vasomotor symptoms, and less commonly, severe thrombotic events such as myocardial infarction. ST-segment elevation myocardial infarction (STEMI) secondary to the hypercoagulable state in ET is a diagnostic challenge as the complication is rare, especially outside the typical demographics affected by ET such as the female and elderly populations. Case presentation: Here we report a case of a 32-year-old male found to have STEMI and a markedly elevated platelet count. Angiography revealed occlusion of the left anterior descending and left circumflex arteries, requiring percutaneous intervention and Impella support. The patient was later diagnosed with essential thrombocythemia, treated with hydroxyurea and antiplatelet therapy, and discharged with a wearable cardioverter defibrillator. Conclusions: This case illustrates the potential for severe thrombotic complications such as STEMI due to ET. Severe thrombotic complications are less common manifestations of ET in general, particularly in young males. Recognition and diagnosis of ET are critical for the institution of appropriate therapy and prevention of STEMI and cardiogenic shock among other complications. [ABSTRACT FROM AUTHOR]

The most common causes of morbidity and mortality in the myeloproliferative neoplasms (MPNs), with the exception of myelofibrosis, are venous and arterial thrombosis, as well as more recently discovered cardiovascular disease (CVD). Clonal hematopoiesis of indeterminate potential (CHIP) is the subclinical finding in an individual of somatic mutations that are also found in clinically overt MPNs and other myeloid malignancies. The prevalence of "silent" CHIP increases with age. CHIP can transform into a clinically overt MPN at an estimated rate of 0.5 to 1% per year. It is likely, therefore, but not proven, that many, if not all, MPN patients had antecedent CHIP, possibly for many years. Moreover, both individuals with asymptomatic CHIP, as well as clinically diagnosed patients with MPN, can develop thrombotic complications. An unexpected and remarkable discovery during the last few years is that even CHIP (as well as MPNs) are significant, independent risk factors for CVD. This review discusses up-to-date information on the types of thrombotic and cardiovascular complications that are found in CHIP and MPN patients. A systemic inflammatory state (that is often subclinical) is most likely to be a major mediator of adverse reciprocal bone marrow–cardiovascular interplay that may fuel the development of progression of MPNs, including its thrombotic and vascular complications, as well as the worsening of cardiovascular disease, possibly in a "vicious cycle". Translating this to clinical practice for hematologists and oncologists who treat MPN patients, attention should now be paid to ensuring that cardiovascular risk factors are controlled and minimized, either by the patient's cardiologist or primary care physician or by the hematologist/oncologist herself or himself. This review is intended to cover the clinical aspects of thrombosis and cardiovascular complications in the MPN, accompanied by pathobiological comments. [ABSTRACT FROM AUTHOR]

Myeloproliferative neoplasms (MPNs) are characterized by an increased production of blood cells due to the acquisition of mutations such as JAK2V617F. TGF‐β, whose secretion is increased in MPN patients, is known to negatively regulate haematopoietic stem cell (HSC) proliferation. Using an isogenic JAK2V617F or JAK2 wild‐type UT‐7 cell line we observed that JAK2V617F cells resist to TGF‐β antiproliferative activity. Although TGF‐β receptors and SMAD2/3 expressions are similar in both cell types, TGF‐β‐induced phosphorylation of SMAD2/3 is reduced in UT‐7 JAK2V617F cells compared with JAK2 WT cells. We confirmed that JAK2V617F mutated cells are resistant to the antiproliferative effect of TGF‐β in a competitive assay as we observed a positive selection of JAK2V617F cells when exposed to TGF‐β. Using cell lines, CD34‐positive cells from MPN patients and bone marrow cells from JAK2V617F knock‐in mice we identified a down regulation of the SHP‐1 phosphatase, which is required for the regulation of HSC quiescence by TGF‐β. The transduction of SHP‐1 cDNA (but not a phosphatase inactive cDNA) restores the antiproliferative effect of TGF‐β in JAK2V617F mutated cells. Finally, SC‐1, a known agonist of SHP‐1, antagonized the selection of JAK2V617F mutated cells in the presence of TGF‐β. In conclusion, we show a JAK2‐dependent down regulation of SHP‐1 in MPN patients' cells which is related to their resistance to the antiproliferative effect of TGF‐β. This may participate in the clonal selection of cancer cells in MPNs. [ABSTRACT FROM AUTHOR]

Clonal hematopoiesis (CH), the expansion of hematopoietic stem cells and their progeny driven by somatic mutations in leukemia-associated genes, is a common phenomenon that rises in prevalence with advancing age to affect most people older than 70 years. CH remains subclinical in most carriers, but, in a minority, it progresses to a myeloid neoplasm, such as acute myeloid leukemia, myelodysplastic syndrome, or myeloproliferative neoplasm. Over the last decade, advances in our understanding of CH, its molecular landscape, and the risks associated with different driver gene mutations have culminated in recent developments that allow for a more precise estimation of myeloid neoplasia risk in CH carriers. In turn, this is leading to the development of translational and clinical programs to intercept and prevent CH from developing into myeloid neoplasia. Here, we give an overview of the spectrum of CH driver mutations, what is known about their pathophysiology, and how this informs the risk of incident myeloid malignancy. [ABSTRACT FROM AUTHOR]

It has been demonstrated previously that human leukocyte antigen class I (HLA-I) and class II (HLA-II) alleles may modulate JAK2 V617F and CALR mutation (CALRmut)-associated oncogenesis in myeloproliferative neoplasms (MPNs). However, the role of immunogenetic factors in MPNs remains underexplored. We aimed to investigate the potential involvement of HLA genes in CALRmut+ MPNs. High-resolution genotyping of HLA-I and -II loci was conducted in 42 CALRmut+ and 158 JAK2 V617F+ MPN patients and 1,083 healthy controls. A global analysis of the diversity of HLA-I genotypes revealed no significant differences between CALRmut+ patients and controls. However, one HLA-I allele (C*06:02) showed an inverse correlation with presence of CALR mutation. A meta-analysis across independent cohorts and healthy individuals from the 1000 Genomes Project confirmed an inverse correlation between the presentation capabilities of the HLA-I loci for JAK2 V617F and CALRmut-derived peptides in both patients and healthy individuals. scRNA-Seq analysis revealed low expression of TAP1 and CIITA genes in CALRmut+ hematopoietic stem and progenitor cells. In conclusion, the HLA-I genotype differentially restricts JAK2 V617F and CALRmut-driven oncogenesis potentially explaining the mutual exclusivity of the two mutations and differences in their presentation latency. These findings have practical implications for the development of neoantigen-based vaccines in MPNs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Ph-negative Myeloproliferative Neoplasm is a rare yet dangerous disease that can turn into more severe forms of disorders later on. Clinical diagnosis of the disease exists but often requires collecting multiple types of pathologies which can be tedious and time-consuming. Meanwhile, studies on deep learning-based research are rare and often need to rely on a small amount of pathological data due to the rarity of the disease. In addition, the existing research works do not address the data scarcity issue apart from using common techniques like data augmentation, which leaves room for performance improvement. To tackle the issue, the proposed research aims to utilize distilled knowledge learned from a larger dataset to boost the performance of a lightweight model trained on a small MPN dataset. Firstly, a 50-layer ResNet model is trained on a large lymph node image dataset of 3,27,680 images, followed by the trained knowledge being distilled to a small 4-layer CNN model. Afterward, the CNN model is initialized with the pre-trained weights to further train on a small MPN dataset of 300 images. Empirical analysis showcases that the CNN with distilled knowledge achieves 97% accuracy compared to 89.67% accuracy achieved by a clone CNN trained from scratch. The distilled knowledge transfer approach also proves to be more effective than more simple data scarcity handling approaches such as augmentation and manual feature extraction. Overall, the research affirms the effectiveness of transferring distilled knowledge to address the data scarcity issue and achieves better convergence when training on a Ph-Negative MPN image dataset with a lightweight model. [ABSTRACT FROM AUTHOR]

Background: Lysosomal dysfunction (LD) impacts cytokine regulation, inflammation, and immune responses, influencing the development and progression of cancer. Inflammation is implicated in the pathogenesis of myeloproliferative neoplasm (MPN). With a hypothesis that LD significantly contributes to MPN carcinogenesis by inducing abnormal inflammation, our objective was to elucidate the pathophysiological mechanisms of MPN arising from an LD background. Methods: Genotyping of the LD background was performed in a cohort of MPN patients (n = 190) and healthy controls (n = 461). Logistic regression modeling, utilizing genotype data, was employed to estimate the correlation between LD and MPN. Whole transcriptome sequencing (WTS) (LD carriers = 8, non‐carriers = 6) and single‐cell RNA sequencing data (LD carriers = 2, non‐carriers = 2, healthy controls = 2) were generated and analyzed. Results: A higher variant frequency of LD was observed in MPN compared to healthy controls (healthy, 4.9%; MPN, 7.8%), with the highest frequency seen in polycythemia vera (PV) (odds ratio = 2.33, p = 0.03). WTS revealed that LD carriers exhibited upregulated inflammatory cytokine ligand–receptor genes, pathways, and network modules in MPNs compared to non‐carriers. At the single‐cell level, there was monocyte expansion and elevation of cytokine ligand–receptor interactions, inflammatory transcription factors, and network modules centered on monocytes. Notably, Oncostatin‐M (OSM) consistently emerged as a candidate molecule involved in the pathogenesis of LD‐related PV. Conclusions: In summary, an LD background is prevalent in MPN patients and leads to increased cytokine dysregulation and inflammation. OSM, as one of the potential molecules, plays a crucial role in PV pathogenesis by impairing lysosomal function. Lysosomal dysfunction (LD) impacts cytokine regulation, inflammation, and immune responses, influencing the development and progression of cancer. Inflammation is implicated in the pathogenesis of myeloproliferative neoplasm (MPN). With a hypothesis that LD significantly contributes to MPN carcinogenesis by inducing abnormal inflammation, our objective was to elucidate the pathophysiological mechanisms of MPN arising from an LD background. Genotyping of the LD background was performed in a cohort of MPN patients (n = 190) and healthy controls (n = 461). Logistic regression modeling, utilizing genotype data, was employed to estimate the correlation between LD and MPN. Whole transcriptome sequencing (WTS) (LD carriers = 8, non‐carriers = 6) and single‐cell RNA‐sequencing data (LD carriers = 2, non‐carriers = 2, healthy controls = 2) were generated and analyzed. A higher variant frequency of LD was observed in MPN compared to healthy controls (healthy, 4.9%; MPN, 7.8%), with the highest frequency seen in polycythemia vera (PV) (odds ratio = 2.33, p = 0.03). WTS revealed that LD carriers exhibited upregulated inflammatory cytokine ligand‐receptor genes, pathways, and network modules in MPNs compared to non‐carriers. At the single‐cell level, there was monocyte expansion and elevation of cytokine ligand‐receptor interactions, inflammatory transcription factors, and network modules centered on monocytes. Notably, Oncostatin‐M (OSM) consistently emerged as a candidate molecule involved in the pathogenesis of LD‐related PV. In summary, an LD background is prevalent in MPN patients and leads to increased cytokine dysregulation and inflammation. OSM may play a crucial role in PV pathogenesis by impairing lysosomal function. [ABSTRACT FROM AUTHOR]

Simple Summary: The development of cancer is associated with coagulation disorders. Blood cancers should be particularly associated with hypercoagulability and thus thromboembolic complications. An essential finding of this study is that arterial thromboembolism (myocardial infarction or stroke) occurs significantly more often than venous thromboembolism (pulmonary embolism or/and thrombosis) preceding the diagnosis of hematological malignancy. Interestingly, venous thromboembolism occurs significantly more often in acute leukemia (myeloid or lymphocytic) and chronic myeloproliferative disease. However, the chance of venous thromboembolism is increased before and after the diagnosis of myeloproliferative disease. More research is needed on the relationship between venous thromboembolism development and myeloproliferative disease progression. Objectives. Venous and arterial thromboembolism (VTE/ATE) often coexist with onco-hematologic diagnosis. This study aimed to assess the time relationship between the diagnosis of VTE/ATE and blood cancers. The second aim was to identify VTE/ATE risk factors related to the type of hematology disease and cardiac history. Methods. A total of 1283 patients underwent cardio-oncology evaluation at the Institute of Hematology and Transfusion Medicine in Warsaw from March 2021 through March 2023 (2 years), and 101 (7.8%) cases were identified with VTE/ATE. Results. ATE compared with VTE significantly occurred more often before the diagnosis and treatment of hematologic malignancy: 33/47 (70.2%) vs. 15/54 (27.8%), p < 0.0001. The risk of a VTE episode is exceptionally high in the first months after the diagnosis of an onco-hematological disease and the initiation of anticancer treatment. The higher frequency of VTE was associated with acute myeloid leukemia (17 cases/270 patients/6.30%/p = 0.055), acute lymphocytic leukemia (7 cases/76 patients/9.21%/p = 0.025), and chronic myeloproliferative disease (7 cases/48 patients/14.58%/p = 0.0003). Only the risk of VTE was significantly increased before (OR = 6.79; 95% CI: 1.85–24.95; p = 0.004) and after diagnosis of myeloproliferative disease (OR = 3.12; 95% CI: 1.06–9.16; p = 0.04). Conclusions. ATEs occur more often than VTE before a diagnosis of blood cancer. The risk of VTE is exceptionally high before and after diagnosis of chronic myeloproliferative disease. [ABSTRACT FROM AUTHOR]

The accurate diagnosis and classification of myelodysplastic/myeloproliferative neoplasm (MDS/MPN) are challenging due to the overlapping pathological and molecular features of myelodysplastic syndrome (MDS) and myeloproliferative neoplasm (MPN). We investigated the genomic landscape in different MDS/MPN subtypes, including chronic myelomonocytic leukemia (CMML; n = 97), atypical chronic myeloid leukemia (aCML; n = 8), MDS/MPN-unclassified (MDS/MPN-U; n = 44), and MDS/MPN with ring sideroblasts and thrombocytosis (MDS/MPN-RS-T; n = 12). Our study indicated that MDS/MPN is characterized by mutations commonly identified in myeloid neoplasms, with TET2 (52%) being the most frequently mutated gene, followed by ASXL1 (38.7%), SRSF2 (34.7%), and JAK2 (19.7%), among others. However, the distribution of recurrent mutations differs across the MDS/MPN subtypes. We confirmed that specific gene combinations correlate with specific MDS/MPN subtypes (e.g., TET2/SRSF2 in CMML, ASXL1/SETBP1 in aCML, and SF3B1/JAK2 in MDS/MPN-RS-T), with MDS/MPN-U being the most heterogeneous. Furthermore, we found that older age (≥65 years) and mutations in RUNX1 and TP53 were associated with poorer clinical outcomes in CMML (p < 0.05) by multivariate analysis. In MDS/MPN-U, CBL mutations (p < 0.05) were the sole negative prognostic factors identified in our study by multivariate analysis (p < 0.05). Overall, our study provides genetic insights into various MDS/MPN subtypes, which may aid in diagnosis and clinical decision-making for patients with MDS/MPN. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: Chronic myeloproliferative neoplasms (MPNs) such as polycythaemia vera (PV) and essential thrombocytosis are associated with atherosclerosis and cardiovascular events, especially if JAK2 mutation is there. In rare cases, also spontaneous coronary artery dissection (SCAD) can be seen. Case Presentation: This case series describes two case reports of MPNs in which SCAD was found in both of them in addition to standard atherosclerosis. First one was about a 42-year-old man who was admitted for acute myocardial infarction (MI) and was later found to have PV and SCAD. The second one was about a 52-year-old man who was also admitted for acute MI and was later found to have SCAD and essential thrombocythemia. JAK2V617F missense mutation was found in both cases. Conclusion: MPNs with JAK2 mutations are associated with SCAD in addition to usual atherosclerosis. This association needs further research. [ABSTRACT FROM AUTHOR]

Objective: Mistake in diagnosis Background: Polycythemia vera (PV) is a myeloproliferative neoplasm (MPNs) marked by elevated hemoglobin and hematocrit, which can lead to thromboembolic events and progress to myelofibrosis or acute myeloid leukemia (AML). MPNs, including PV, are relatively rare in Malaysia, and there is currently no recent published data reporting the demographics and outcomes of PV patients in the country. In Western countries, routine annual blood tests are standard, whereas this practice is less common in Malaysia, underscoring the need for improved awareness and accessibility to ensure timely diagnosis of PV. Case Report: This report presents a case of a 55-year-old Malaysian woman in a primary care setting, initially misdiagnosed with benign conditions due to atypical presentations of recurrent bilateral eye redness and dizziness. Persistent symptoms led to further evaluation by primary care and hematologist, which revealed elevated hemoglobin, hematocrit, leukocytosis, JAK2 V617F mutation, and low serum erythropoietin levels, confirming PV, even without proceeding with a bone marrow biopsy. Treatment with phlebotomy, hydroxyurea, and aspirin resulted in significant improvements in ocular symptoms and hematological parameters within 60 days. Conclusions: This case underscores the critical role of primary care in the early detection of polycythemia vera. Timely identification and appropriate referral from primary care settings are essential to avoid diagnostic delays and ensure effective management, improving patient outcomes and preventing complications. [ABSTRACT FROM AUTHOR]

Background: Myelofibrosis (MF) is a myeloproliferative neoplasm characterized by bone marrow fibrosis associated with substantial morbidity and mortality. The therapeutic landscape for MF has advanced with the development of Janus kinase inhibitors (JAKis) like ruxolitinib (RUX), fedratinib (FED), pacritinib (PAC), and momelotinib (MMB), aiming to alleviate symptoms and enhance patient comfort. Methods: A network meta-analysis was conducted to assess the efficacy and safety of eleven JAKi treatment regimens across nine randomized controlled trials (RCTs) with a total of 2340 participants. Outcomes were evaluated in terms of spleen volume reduction (SVR), total symptom score reduction (TSSR), hematological safety profiles, and overall survival (OS). Results: RUX and MMB were superior in achieving SVR and TSSR, with significant dose-response relationships observed. PAC and MMB were associated with a decreased risk of grade 3/4 anemia and thrombocytopenia compared to other JAKis. However, no substantial benefits in OS were observed with newer JAKis compared to RUX. The poorer OS outcomes with certain PAC dosages were likely influenced by baseline patient characteristics, particularly severe cytopenias. Conclusion: The introduction of JAKis significantly changed the treatment of MF. This meta-analysis reaffirms the core role of RUX and positions MMB as a potentially powerful alternative for treating symptoms and reducing spleen size. Meanwhile, MMB and PAC have a positive effect on anemia in MF while FED is more tolerable for patients with thrombocytopenia. However, it should be noted that these results are influenced by baseline patient characteristics, particularly cytopenias, which affects both management and overall survival. Therefore, there is an urgent need for personalized dosing strategies to optimize the balance between efficacy and safety, with careful consideration of patientspecific factors. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNA) are a class of multifunctional non-coding RNAs with a covalently ring structure, playing a variety of biological roles within cells. Chronic myelogenous leukemia (CML) is a myeloproliferative disorder originating from hematopoietic stem cells and progenitor cells. Although the current research on circRNA in CML is not yet comprehensive, evidence has shown that circRNA plays a significant role in the onset and progression of CML. This review summarizes the involvement of circRNA in CML, particularly focusing on its contribution to tyrosine kinase inhibitors (TKIs) resistance, and discusses the potential utility of circRNA for diagnosing and assessing prognosis in CML. The objective is to provide researchers with an up-to-date overview of the role of circRNA in CML and offer references for future research endeavors. [ABSTRACT FROM AUTHOR]

Simple Summary: JAK2 V617F is a somatic mutation related with myeloproliferative neoplasm (MPN) and it is associated with the germline GGCC (46/1) haplotype. Nowadays, there are no studies focused on the association between the JAK2 haplotype GGCC_46/1 and the onset of onco-drug resistance. Thus, we looked for the haplotype 46/1 in JAK2V617F-positive patients, and we studied their therapy response. Most of the patients with onco-drug resistance had the C/G allele. Instead, the G risk allele, represented by few patients because of its reduced frequency in the general population, was shown to be associated with MPNs' evolution to myelofibrosis and to onco-drug resistance clinical parameters. These findings represent a significant advance in MPN management, although an in-depth analysis on a larger sample is required. We believe that the integration of a comprehensive genetic profiling into treatment decisions may influence the disease progression, prognosis, and treatment efficacy. Background: JAK2 V617F is a somatic mutation associated with myeloproliferative neoplasms (MPNs) including polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF). In MPNs, this mutation is associated with the germline GGCC (46/1) haplotype. Several studies associated JAK2 haplotype GGCC_46/1 with some MPNs clinical parameters, but not one explore the link between JAK2 haplotype GGCC_46/1 and onco-drug resistance. Thus, we assessed for the JAK2 46/1 haplotype's correlation with therapy response in JAK2 V617F-positive patients. Methods: Patients with MPN, selected by the Hematology Laboratory of "V. Fazzi" Hospital (LE), were analyzed with RLFP-PCR assay with rs10974944 SNP. Results: Results show how the majority of patients had PV (63%) or PMF (61%) and that 58% of patients who developed drug resistance had the C/G genotype, while only 11% had the G/G allele. While no direct correlation between JAK2 46/1 haplotype variants and drug resistance was found, the G/G allele was associated with disease progression to myelofibrosis and certain resistance-related clinical parameters (p = 0.002449, odds ratio = 3.701209). Conclusions: Although other analyses are required, due to the narrow cardinality of sample, our findings suggest how the G/G allele could be useful for MPNs diagnosis and for the prediction of the disease outcome. [ABSTRACT FROM AUTHOR]

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by bone marrow expansion and the proliferation of one or more myeloid cell lineages, predominantly driven by the expression of the constitutively active fusion product tyrosine kinase BCR:ABL1. Rarely, CML patients directly develop a blast crisis (BC), mostly of myeloid origin. CML at blast crisis with a T-cell phenotype at diagnosis, without any prior history of CML, is extremely rare. Herein, we describe one rare CML case, in a young man showing an unusual and early T-lymphoid blastic crisis at diagnosis, as the first onset of a previously unknown CML. The multidisciplinary collaboration between laboratorians and clinicians for the diagnosis and management of this atypical case was crucial in outlining both a targeted pharmacological treatment and a successful hematopoietic stem cell transplantation. [ABSTRACT FROM AUTHOR]

Noonan syndrome (NS) is an autosomal dominant disorder that varies in severity and can involve multiple organ systems. In approximately 50% of cases, it is caused by missense mutations in the PTPN11 gene (12q24.13). NS is associated with a higher risk of cancer occurrence, specifically hematological disorders. Here, we report a case of a child who was diagnosed at birth with a transient myeloproliferative disorder (TMD). After two years, the child developed hyperdiploid B-cell precursor acute lymphoblastic leukemia (BCP-ALL), receiving a two-year course of treatment. During her continuous complete remission (CCR), a heterozygous germline mutation in the PTPN11 gene [c.218 C>T (p.Thr73lle)] was identified. At the age of ten, the child presented with massive splenomegaly, hyperleukocytosis, and thrombocytopenia, resulting in the diagnosis of juvenile myelomonocytic leukemia (JMML). After an initial response to antimetabolite therapy (6-mercaptopurine), she underwent haploidentical hematopoietic stem cell transplantation (HSCT) and is currently in complete remission. The goal of this review is to gain insight into the various hematological diseases associated with NS, starting from our unique case. [ABSTRACT FROM AUTHOR]

The Myeloproliferative Neoplasm Symptom Assessment Total Symptom Score (MPN-SAF TSS) is a surrogate marker for symptom evaluation in chronic myeloproliferative neoplasms (MPNs). However, insufficient data are available regarding the relationship among the MPN-SAF TSS, JAK2 mutation allele burden, and thrombosis. In this retrospective analysis, we aimed to determine the genetic burdens, clinical features, and relationships with MPN-SAF TSS in MPN patients. One hundred thirty JAK2V617F-positive patients with MPNs were included in our study. We calculated the MPN-SAF TSS for all patients and compared it with their clinical characteristics. Patients with higher JAK2V617F mutation allele burden had higher MPN-SAF TSS values (p=0.008). Patients with thrombosis had higher MPN-SAF TSS than patients without thrombosis (p=0.003). The mean MPN-SAF TSS was higher in patients with primary myelofibrosis compared to those with polycythemia vera and essential thrombocythemia. Thrombosis was associated with increased symptom severity in several domains, including fatigue, abdominal discomfort, inactivity, night sweats, pruritus, weight loss, and early satiety. Additionally, an increase in JAK2 allele burden was observed with higher symptom scores. The MPNSAF TSS proved to be a reliable tool for assessing symptom burden in Turkish MPN patients. Furthermore, the significant association between thrombosis occurrence and symptom severity suggests that thrombotic events may contribute to symptom development. Notably, increasing JAK2 allele burden was correlated with more severe symptoms, highlighting its potential role in predicting disease burden. This study emphasizes the importance of symptom assessment in MPN patients and supports the incorporation of the MPN-SAF TSS in routine clinical practice to enhance patient care and management. [ABSTRACT FROM AUTHOR]

Objective: It has been shown that clonal mutations occur in hematopoietic stem cells with advancing age and increase the risk of death due to atherosclerotic vascular diseases, similarly to myeloproliferative neoplasms. Endothelial cells (ECs) and hematopoietic stem cells develop from common stem cells called hemangioblasts in the early embryonic period. However, the presence of hemangioblasts in the postnatal period is controversial. In this study, JAK2 gene variants were examined in patients with atherosclerotic carotid disease and without any hematological malignancies. Materials and Methods: Ten consecutive patients (8 men and 2 women) with symptomatic atherosclerotic carotid stenosis were included in this study. ECs (CD31+CD45-) were separated from tissue samples taken by carotid endarterectomy. JAK2 variants were examined in ECs, peripheral blood mononuclear cells, and oral epithelial cells of the patients with next-generation sequencing. Results: The median age of the patients was 74 (range: 58-80) years and the median body mass index value was 24.44 (range: 18.42- 30.85) kg/m2. Smoking history was present in 50%, hypertension in 80%, diabetes in 70%, and ischemic heart disease in 70% of the cases. The JAK2V617F mutation was detected in the peripheral blood mononuclear cells of 3 of the 10 patients, and 2 patients also had the JAK2V617F mutation in their ECs. The JAK2V617F mutation was not found in the oral epithelial cells of any of the patients. Conclusion: In this study, for the first time in the literature, we showed that the JAK2V617F mutation was found somatically in both peripheral blood cells and ECs in patients with atherosclerosis. This finding may support that ECs and hematopoietic cells originate from a common clone or that somatic mutations can be transmitted to ECs by other mechanisms. Examining the molecular and functional changes caused by the JAK2V617F mutation in ECs may help open a new avenue for treating atherosclerosis. [ABSTRACT FROM AUTHOR]

The authors present the case of a 39-year-old male with an initial diagnosis of de novo acute myeloid leukemia who, despite complete remission without measurable residual disease after conventional induction chemotherapy, presented with persistent splenomegaly and eosinophilia. As reactive eosinophilia was excluded and CBFB::MYH11 and RUNX1::RUNX1T1 gene fusions were not identified in additional molecular studies, we decided to test for other causes of clonal eosinophilia. Cytogenetic and molecular testing identified FIP1L1::PDGFRA gene fusion and prompted the introduction of imatinib. The initial diagnosis of de novo acute myeloid leukemia was changed to myeloid/lymphoid neoplasm with eosinophilia and FIP1L1::PDGFRA in the blast phase as myeloid blast count in the bone marrow at the diagnosis was >20%. The patient has maintained a complete molecular response with imatinib at a dose of 100 mg for more than two years. [ABSTRACT FROM AUTHOR]

Inflammation is associated with an increased risk of developing various cancers in both animals and humans, primarily solid tumors but also myeloproliferative neoplasms (MPNs), myelodysplastic syndromes (MDS), and acute myeloid leukemia (AML). Multi-walled carbon nanotubes (MWCNTs), a type of carbon nanotubes (CNTs) increasingly used in medical research and other fields, are leading to a rising human exposure. Our study demonstrated that exposing mice to MWCNTs accelerated the progression of spontaneous MOL4070LTR virus-induced leukemia. Additionally, similar exposures elevated pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α and induced reactive oxygen species (ROS) in a murine macrophage cell line. These effects were significantly reduced in immunodeficient mice and when mice were treated with methoxypolyethylene glycol amine (PEG)-modified MWCNTs. These findings underscore the necessity of evaluating the safety of MWCNTs, particularly for those with hematologic cancers. [ABSTRACT FROM AUTHOR]

Abstract Myelofibrosis (MF) is a complex myeloproliferative neoplasm characterized by abnormal hematopoietic stem cell proliferation and subsequent bone marrow (BM) fibrosis. First documented in the late 19th century, MF has since been extensively studied to unravel its pathophysiology, clinical phenotypes, and therapeutic interventions. MF can be classified into primary and secondary forms, both driven by mutations in genes such as JAK2, CALR, and MPL, which activate the JAK-STAT signaling pathway. These driver mutations are frequently accompanied by additional non-driver mutations in genes like TET2, SRSF2, and TP53, contributing to disease complexity. The BM microenvironment, consisting of stromal cells, extracellular matrix, and cytokines such as TGF-β and TNF-α, plays a critical role in fibrosis and aberrant hematopoiesis. Clinically, MF manifests with symptoms ranging from anemia, splenomegaly, and fatigue to severe complications such as leukemic transformation. Splenomegaly, caused by extramedullary hematopoiesis, leads to abdominal discomfort and early satiety. Current therapeutic strategies include JAK inhibitors like Ruxolitinib, which target the JAK-STAT pathway, alongside supportive treatments such as blood transfusions, erythropoiesis-stimulating agents and developing combinatorial approaches. Allogeneic hematopoietic stem cell transplantation remains the only curative option, though it is limited to younger, high-risk patients. Recently approved JAK inhibitors, including Fedratinib, Pacritinib, and Momelotinib, have expanded the therapeutic landscape. Spatially Resolved Transcriptomics (SRT) has revolutionized the study of gene expression within the spatial context of tissues, providing unprecedented insights into cellular heterogeneity, spatial gene regulation, and microenvironmental interactions, including stromal-hematopoietic dynamics. SRT enables high-resolution mapping of gene expression in the BM and spleen, revealing molecular signatures, spatial heterogeneity, and pathological niches that drive disease progression. These technologies elucidate the role of the spleen in MF, highlighting its transformation into a site of abnormal hematopoietic activity, fibrotic changes, and immune cell infiltration, functioning as a “tumor surrogate.” By profiling diverse cell populations and molecular alterations within the BM and spleen, SRT facilitates a deeper understanding of MF pathophysiology, helping identify novel therapeutic targets and biomarkers. Ultimately, integrating spatial transcriptomics into MF research promises to enhance diagnostic precision and therapeutic innovation, addressing the multifaceted challenges of this disease.

Abstract DNA methyltransferase 3 A mutations (DNMT3A MT) are frequent in myeloid neoplasia (MN) and mostly heterozygous. However, cases with multiple DNMT3A MT can be also encountered but their clinical and genetic landscape remains unexplored. We retrospectively analyzed 533 cases with DNMT3A MT identified out of 5,603 consecutive MNs, of whom 8.4% had multiple DNMT3A MT hits. They were most frequent in acute myeloid leukemia (AML) with R882 variant accounting for 13.3% of the multi-hits. Multiple DNMT3A MT more likely coincided with IDH2 (P = 0.005) and ETV6 (P = 0.044) mutations compared to patients with single DNMT3A MT. When the sum of variant allele frequencies (VAFs) for multiple DNMT3A MT exceeded 60%, we found a significant positive clonal burden correlation of the two DNMT3A variants (P

Objective: It has been shown that clonal mutations occur in hematopoietic stem cells with advancing age and increase the risk of death due to atherosclerotic vascular diseases, similarly to myeloproliferative neoplasms. Endothelial cells (ECs) and hematopoietic stem cells develop from common stem cells called hemangioblasts in the early embryonic period. However, the presence of hemangioblasts in the postnatal period is controversial. In this study, JAK2 gene variants were examined in patients with atherosclerotic carotid disease and without any hematological malignancies. Materials and Methods: Ten consecutive patients (8 men and 2 women) with symptomatic atherosclerotic carotid stenosis were included in this study. ECs (CD31+CD45-) were separated from tissue samples taken by carotid endarterectomy. JAK2 variants were examined in ECs, peripheral blood mononuclear cells, and oral epithelial cells of the patients with next-generation sequencing. Results: The median age of the patients was 74 (range: 58-80) years and the median body mass index value was 24.44 (range: 18.42- 30.85) kg/m2. Smoking history was present in 50%, hypertension in 80%, diabetes in 70%, and ischemic heart disease in 70% of the cases. The JAK2V617F mutation was detected in the peripheral blood mononuclear cells of 3 of the 10 patients, and 2 patients also had the JAK2V617F mutation in their ECs. The JAK2V617F mutation was not found in the oral epithelial cells of any of the patients. Conclusion: In this study, for the first time in the literature, we showed that the JAK2V617F mutation was found somatically in both peripheral blood cells and ECs in patients with atherosclerosis. This finding may support that ECs and hematopoietic cells originate from a common clone or that somatic mutations can be transmitted to ECs by other mechanisms. Examining the molecular and functional changes caused by the JAK2V617F mutation in ECs may help open a new avenue for treating atherosclerosis.

The Myeloproliferative Neoplasm Symptom Assessment Total Symptom Score (MPN-SAF TSS) is a surrogate marker for symptom evaluation in chronic myeloproliferative neoplasms (MPNs). However, insufficient data are available regarding the relationship among the MPN-SAF TSS, JAK2 mutation allele burden, and thrombosis. In this retrospective analysis, we aimed to determine the genetic burdens, clinical features, and relationships with MPN-SAF TSS in MPN patients. One hundred thirty JAK2V617F-positive patients with MPNs were included in our study. We calculated the MPN-SAF TSS for all patients and compared it with their clinical characteristics. Patients with higher JAK2V617F mutation allele burden had higher MPN-SAF TSS values (p=0.008). Patients with thrombosis had higher MPN-SAF TSS than patients without thrombosis (p=0.003). The mean MPN-SAF TSS was higher in patients with primary myelofibrosis compared to those with polycythemia vera and essential thrombocythemia. Thrombosis was associated with increased symptom severity in several domains, including fatigue, abdominal discomfort, inactivity, night sweats, pruritus, weight loss, and early satiety. Additionally, an increase in JAK2 allele burden was observed with higher symptom scores. The MPNSAF TSS proved to be a reliable tool for assessing symptom burden in Turkish MPN patients. Furthermore, the significant association between thrombosis occurrence and symptom severity suggests that thrombotic events may contribute to symptom development. Notably, increasing JAK2 allele burden was correlated with more severe symptoms, highlighting its potential role in predicting disease burden. This study emphasizes the importance of symptom assessment in MPN patients and supports the incorporation of the MPN-SAF TSS in routine clinical practice to enhance patient care and management.

Myeloproliferative neoplasms (MPNs), encompassing disorders like polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), are characterized by clonal hematopoiesis without the Philadelphia chromosome. The JAK2 V617F mutation is prevalent in PV, ET, and PMF, while mutations in MPL and CALR also play significant roles. These conditions predispose patients to thrombotic events, with PMF exhibiting the lowest survival among MPNs. Chronic inflammation, driven by cytokine release from aberrant leukocytes and platelets, amplifies cardiovascular risk through various mechanisms, including atherosclerosis and vascular remodeling. Additionally, MPN-related complications like pulmonary hypertension and cardiac fibrosis contribute to cardiovascular morbidity and mortality. This review consolidates recent research on MPNs’ cardiovascular implications, emphasizing thrombotic risk, chronic inflammation, and vascular stiffness. Understanding these associations is crucial for developing targeted therapies and improving outcomes in MPN patients.

Abstract Background Blast transformation is a rare but well-recognized event in Philadelphia-negative myeloproliferative neoplasms associated with a poor prognosis. Secondary acute myeloid leukemias evolving from myeloproliferative neoplasms are characterized by a unique set of cytogenetic and molecular features distinct from de novo disease. t(8;21) (q22;q22.1); RUNX1::RUNX1T1, one of the most frequent cytogenetic abnormalities in de novo acute myeloid leukemia, is rarely observed in post-myeloproliferative neoplasm acute myeloid leukemia. Here we report a case of secondary acute myeloid leukemia with t(8;21) evolving from JAK2-mutated essential thrombocythemia. Case presentation The patient was a 74-year-old Japanese woman who was referred because of thrombocytosis (platelets 1046 × 109/L). Bone marrow was hypercellular with increase of megakaryocytes. Chromosomal analysis presented normal karyotype and genetic test revealed JAK2 V617F mutation. She was diagnosed with essential thrombocythemia. Thrombocytosis had been well controlled by oral administration of hydroxyurea; 2 years after the initial diagnosis with ET, she presented with leukocytosis (white blood cells 14.0 × 109/L with 82% of blasts), anemia (hemoglobin 91 g/L), and thrombocytopenia (platelets 24 × 109/L). Bone marrow was hypercellular and filled with 80% of myeloperoxidase-positive blasts bearing Auer rods. Chromosomal analysis revealed t(8;21) (q22;q22.1) and flow cytometry presented positivity of CD 13, 19, 34, and 56. Molecular analysis showed the coexistence of RUNX1::RUNX1T1 chimeric transcript and heterozygous JAK2 V617F mutation in leukemic blasts. She was diagnosed with secondary acute myeloid leukemia with t(8;21)(q22;q22.1); RUNX1::RUNX1T1 evolving from essential thrombocythemia. She was treated with combination chemotherapy with venetoclax and azacytidine. After the first cycle of the therapy, blasts disappeared from peripheral blood and decreased to 1.4% in bone marrow. After the chemotherapy, RUNX1::RUNX1T1 chimeric transcript disappeared, whereas mutation of JAK2 V617F was still present in peripheral leukocytes. Conclusions To our best knowledge, the present case is the first one with JAK2 mutation preceding the acquisition of t(8;21). Our result suggests that t(8;21); RUNX1::RUNX1T1 can be generated as a late event in the progression of JAK2-mutated myeloproliferative neoplasms. The case presented typical morphological and immunophenotypic features associated with t(8;21) acute myeloid leukemia.

Background. The COVID-19 pandemic, which swept the world in 2020–2021, had a significant impact on the epidemiological picture of hematological malignancies. Aim. To study the dynamics of epidemiological indicators of five chronic hemoblastoses in Moscow over a 12-year period, and also to assess the impact of the COVID-19 pandemic on these indicators. Materials and methods. A population-based study was conducted for five types of oncohematological diseases: multiple myeloma, Hodgkin's lymphoma, follicular lymphoma, chronic lymphocytic leukemia, chronic myeloid leukemia. The annual rates of morbidity, mortality, prevalence of these nosologies, overall survival, and expected overall survival were calculated. Gender and age characteristics for each disease were determined. Results and discussion. The present study showed a uniform increase in the incidence and prevalence of five hematological malignancies between 2012 and 2019. Convincing evidence of an increase in mortality and a decrease in the number of diagnosed cases in comparison with the expected figures for these hematological malignancies in 2020–2021 was presented. A greater reduction was shown for cases diagnosed at early stages compared to later ones. During the pandemic, a significant increase in mortality was recorded among patients with chronic lymphocytic leukemia and multiple myeloma, while in cohorts of patients with chronic myeloid leukemia and Hodgkin lymphoma it increased slightly. The return of morbidity, mortality and prevalence rates to the original dynamics in 2022–2023 has been demonstrated. Conclusion. This study demonstrated the features of the regional pattern of incidence, mortality, prevalence and gender-age characteristics of five hematological malignancies and provided the changes in the indicators dynamics of different hematological malignancies during the COVID-19 pandemic.

Abstract DARS, encoding for aspartyl-tRNA synthetase, is implicated in the pathogenesis of various cancers, including renal cell carcinoma, glioblastoma, colon cancer, and gastric cancer. Its role in BCR/ABL1-negative myeloproliferative neoplasms (MPNs), however, remains unexplored. This study aimed to elucidate the expression of DARS in patients with MPNs (PV 23, ET 19, PMF 16) through immunohistochemical analysis and to examine the profiles of circulating immune cells and cytokines using flow cytometry. Our findings indicate a significant overexpression of DARS in all MPNs subtypes at the protein level compared to controls (P

Precise quantification of the JAK2V617F mutation using highly sensitive assays is crucial for diagnosis, treatment process monitoring, and prognostic prediction in myeloproliferative neoplasms' (MPNs) patients. Digital droplet polymerase chain reaction (ddPCR) enables precise quantification of low-level mutations amidst a high percentage of wild type alleles without the need for external calibrators or endogenous controls. The objective of this study was to optimize a ddPCR assay for detecting the JAK2V617F mutation and establish it as a laboratory-developed ddPCR assay in our center. The optimization process involved fine-tuning five key parameters: primer/probe sequences and concentrations, annealing temperature, template amount, and PCR cycles. Our ddPCR assay demonstrated exceptional sensitivity, and the limit of quantification (LoQ) was 0.01% variant allele frequency with a coefficient of variation of approximately 76%. A comparative analysis with quantitative PCR on 39 samples showed excellent consistency (r = 0.988).

Background: Blast transformation is a rare but well-recognized event in Philadelphia-negative myeloproliferative neoplasms associated with a poor prognosis. Secondary acute myeloid leukemias evolving from myeloproliferative neoplasms are characterized by a unique set of cytogenetic and molecular features distinct from de novo disease. t(8;21) (q22;q22.1); RUNX1::RUNX1T1, one of the most frequent cytogenetic abnormalities in de novo acute myeloid leukemia, is rarely observed in post-myeloproliferative neoplasm acute myeloid leukemia. Here we report a case of secondary acute myeloid leukemia with t(8;21) evolving from JAK2-mutated essential thrombocythemia. Case presentation: The patient was a 74-year-old Japanese woman who was referred because of thrombocytosis (platelets 1046 × 109/L). Bone marrow was hypercellular with increase of megakaryocytes. Chromosomal analysis presented normal karyotype and genetic test revealed JAK2 V617F mutation. She was diagnosed with essential thrombocythemia. Thrombocytosis had been well controlled by oral administration of hydroxyurea; 2 years after the initial diagnosis with ET, she presented with leukocytosis (white blood cells 14.0 × 109/L with 82% of blasts), anemia (hemoglobin 91 g/L), and thrombocytopenia (platelets 24 × 109/L). Bone marrow was hypercellular and filled with 80% of myeloperoxidase-positive blasts bearing Auer rods. Chromosomal analysis revealed t(8;21) (q22;q22.1) and flow cytometry presented positivity of CD 13, 19, 34, and 56. Molecular analysis showed the coexistence of RUNX1::RUNX1T1 chimeric transcript and heterozygous JAK2 V617F mutation in leukemic blasts. She was diagnosed with secondary acute myeloid leukemia with t(8;21)(q22;q22.1); RUNX1::RUNX1T1 evolving from essential thrombocythemia. She was treated with combination chemotherapy with venetoclax and azacytidine. After the first cycle of the therapy, blasts disappeared from peripheral blood and decreased to 1.4% in bone marrow. After the chemotherapy, RUNX1::RUNX1T1 chimeric transcript disappeared, whereas mutation of JAK2 V617F was still present in peripheral leukocytes. Conclusions: To our best knowledge, the present case is the first one with JAK2 mutation preceding the acquisition of t(8;21). Our result suggests that t(8;21); RUNX1::RUNX1T1 can be generated as a late event in the progression of JAK2-mutated myeloproliferative neoplasms. The case presented typical morphological and immunophenotypic features associated with t(8;21) acute myeloid leukemia. [ABSTRACT FROM AUTHOR]

Polycythemia vera is an indolent myeloproliferative disorder that predisposes patients to venous and arterial thrombosis and can transform into myelofibrosis and acute myeloid leukemia. Consistent phlebotomy prevents life-threatening cerebrovascular and coronary artery disease and prolongs survival in low-risk polycythemia vera (patients under 60 years without thrombosis). However, despite its effectiveness in preventing serious complications, phlebotomy does not necessarily enhance the quality of life (QoL). This review assesses QoL issues associated with low-risk PV, explores alternative management strategies such as erythrocytapheresis, and discusses the roles of hydroxyurea, peginterferon, ruxolitinib, and other novel agents in potentially improving disease management and patient outcomes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

We investigated the role of toll‐like receptors (TLRs) in inflammatory pathways in Philadelphia chromosome‐negative myeloproliferative neoplasms (Ph(−)MPNs). TLR2 expression was increased in ET, PV, and MPN (grouped as (PV + (ET) + MF)), whereas TLR4 was elevated only in MPN. TLR3, 7, and 9 were not elevated. Cultured monocyte‐derived dendritic cells and plasma assays in TLR2‐elevated patients were found to secrete more cytokines than those from TLR2‐normal patients. These facts suggest that TLR2 is the major inflammatory pathways in MPN. We also measured S100A9 and reactive oxygen species (ROS), revealing increased S100A9 in PV, MF, and MPN, while ROS were only increased in MF. These data suggests that MPNs initially involve TLR2, with minor contributions from TLR4, and with S100A9, leading to ROS formation, JAK2 mutation, and progression to MF or leukemia. Furthermore, patients with JAK2 mutations or leukocytosis exhibited higher TLR2 expression. In leukocyte–platelet interactions, cells from MPN patients displayed a stronger response to a TLR2 agonist than TLR4 agonist. A TLR2 inhibitor (but not a TLR4 inhibitor) attenuated this response. Thrombosis incidence was higher in TLR2‐elevated patients (29%) than in TLR2‐normal patients (19%). These findings suggest that TLR2 likely contributes to thrombosis in MPN. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Simple Summary: Juvenile Myelomonocytic Leukemia (JMML) is a rare and clonal hematopoietic disorder of infancy and early childhood with myeloproliferative/myelodysplastic features resulting from germline or somatic mutations in the RAS pathway. Given its rarity, management is not standardized and varies widely, ranging from observation to bone marrow transplant depending on genomic and clinical features. We describe the course of JMML or Noonan Syndrome-associated Myeloproliferative Disorder in 22 pediatric patients treated at three institutions to provide guidance for monitoring versus intervention, including transplant, supported by patient outcomes. We provide additional insight into the expected time to spontaneous resolution in those with germline PTPN11 mutations and treatment approaches for patients with germline CBL mutations where no standard exists. Juvenile Myelomonocytic Leukemia (JMML) is a rare and clonal hematopoietic disorder of infancy and early childhood with myeloproliferative/myelodysplastic features resulting from germline or somatic mutations in the RAS pathway. Treatment is not uniform, with management varying from observation to stem cell transplant. The aim of our retrospective review is to describe the treatment and outcomes of a cohort of patients with JMML or Noonan Syndrome-associated Myeloproliferative Disorder (NS-MPD) to provide management guidance for this rare and heterogeneous disease. We report on 22 patients with JMML or NS-MPD managed at three institutions in the Texas Medical Center. Of patients with known genetic mutations and cytogenetics, 6 harbored germline mutations, 12 had somatic mutations, and 9 showed cytogenetic abnormalities. Overall, 14/22 patients are alive. Spontaneous clinical remission occurred in one patient with somatic NRAS mutation, as well as two with germline PTPN11 mutations with NS-MPD, and two others with germline PTPN11 mutations and NS-MPD remain under surveillance. Patients with NS-MPD were excluded from treatment analysis as none required chemotherapeutic intervention. All patients (5/5) treated with 5-azacitidine alone and one of the four treated with 6-mercaptopurine monotherapy had a reduction in mutant variant allele frequency. Transformation to acute myeloid leukemia was seen in two patients who both died. Among patients who received transplants, 7/13 are alive, and relapse post-transplant occurred in 3/13 with a median time to relapse of 3.55 months. This report provides insight into therapy responses and long-term outcomes across different genetic subsets of JMML and lends insight into the expected time to spontaneous resolution in patients with NS-MPD with germline PTPN11 mutations. [ABSTRACT FROM AUTHOR]

Myelofibrosis is a chronic myeloproliferative disorder characterized by bone marrow fibrosis, splenomegaly, anemia, and constitutional symptoms, with a median survival of ≈6 years from diagnosis. While currently approved Janus kinase (JAK) inhibitors (ruxolitinib, fedratinib) improve splenomegaly and symptoms, most can exacerbate myelofibrosis‐related anemia, a negative prognostic factor for survival. Momelotinib is a novel JAK1/JAK2/activin A receptor type 1 (ACVR1) inhibitor approved in the US, European Union, and the UK and is the first JAK inhibitor indicated specifically for patients with myelofibrosis with anemia. Momelotinib not only addresses the splenomegaly and symptoms associated with myelofibrosis by suppressing the hyperactive JAK–STAT (signal transducer and activator of transcription) pathway but also improves anemia and reduces transfusion dependency through ACVR1 inhibition. The recommended dose of momelotinib is 200 mg orally once daily, which was established after review of safety, efficacy, pharmacokinetic, and pharmacodynamic data. Momelotinib is metabolized primarily by CYP3A4 and excreted as metabolites in feces and urine. Steady‐state maximum concentration is 479 ng/mL (CV%, 61%), with a mean AUCtau of 3288 ng.h/mL (CV%, 60%); its major metabolite, M21, is active (≈40% of pharmacological activity of parent), with a metabolite‐to‐parent AUC ratio of 1.4–2.1. This review describes momelotinib's mechanism of action, detailing how the JAK–STAT pathway is involved in myelofibrosis pathogenesis and ACVR1 inhibition decreases hepcidin, leading to improved erythropoiesis. Additionally, it summarizes the pivotal studies and data that informed the recommended dosage and risk/benefit assessment. [ABSTRACT FROM AUTHOR]

Leukemia represents a diverse group of hematopoietic neoplasms that can be classified into different subtypes based on the molecular aberration in the affected cell population. Identification of these molecular classification is required to identify specific targeted therapeutic approaches for each leukemic subtype. In general, targeted therapy approaches achieve good responses in some leukemia subgroups, however, resistance against these targeted therapies is common. In this review, we summarize molecular drug resistance biomarkers in targeted therapies in BCR::ABL1-driven chronic myeloid leukemia (CML) and JAK2-driven myeloproliferative neoplasms (MPNs). While acquisition of secondary mutations in the BCR::ABL1 kinase domain is the a common mechanism associated with TKI resistance in CML, in JAK2-driven MPNs secondary mutations in JAK2 are rare. Due to high prevalence and lack of specific therapy approaches in MPNs compared to CML, identification of crucial pathways leading to inhibitor persistence in MPN model is utterly important. In this review, we focus on different alternative signaling pathways activated in both, BCR::ABL1-mediated CML and JAK2-mediated MPNs, by combining data from in vitro and in vivo-studies that could be used as potential biomarkers of drug resistance. In a nutshell, some common similarities, especially activation of PDGFR, Ras, PI3K/Akt signaling pathways, have been demonstrated in both leukemias. In addition, induction of the nucleoprotein YBX1 was shown to be involved in TKI-resistant JAK2-mediated MPN, as well as TKI-resistant CML highlighting deubiquitinating enzymes as potential biomarkers of TKI resistance. Taken together, whole exome sequencing of cell-based or patients-derived samples are highly beneficial to define specific resistance markers. Additionally, this might be helpful for the development of novel diagnostic tools, e.g., liquid biopsy, and novel therapeutic agents, which could be used to overcome TKI resistance in molecularly distinct leukemia subtypes. [ABSTRACT FROM AUTHOR]

Background: Ruxolitinib has been approved by the US FDA for the treatment of myeloproliferative neoplasms such as polycythemia vera and primary myelofibrosis. Ruxolitinib will remain a main stay in the treatment of MPN patients due to its effective therapeutic benefits. However, there have been instances of ruxolitinib resistance in MPN patients. As JAK2 is a direct target of ruxolitinib, we generated ruxolitinib-resistant clones to find out the mechanism of resistance. Methods: Cell-based screening strategy was used to detect the ruxolitinibresistant mutations in JAK2. The Sanger sequencing method was used to detect the point mutations in JAK2. Mutations were re-introduced using the site-directed mutagenesis method and stably expressed in Ba/F3 cells. Drug sensitivities against the JAK2 inhibitors were measured using an MTS-based assay. JAK2 and STAT5 activation levels and total proteins were measured using immunoblotting. Computational docking studies were performed using the Glide module of Schrodinger Maestro software. Results: In this study, we have recovered seven residues in the kinase domain of JAK2 that affect ruxolitinib sensitivity. All these mutations confer cross-resistance across the panel of JAK2 kinase inhibitors except JAK2-L983F. JAK2-L983F reduces the sensitivity towards ruxolitinib. However, it is sensitive towards fedratinib indicating that our screen identifies the drug-specific resistance profiles. All the ruxolitinib-resistant JAK2 variants displayed sensitivity towards type II JAK2 inhibitor CHZ-868. In this study, we also found that JAK1-L1010F (homologous JAK2-L983F) is highly resistant towards ruxolitinib suggesting the possibility of JAK1 escape mutations in JAK2-driven MPNs and JAK1 mutated ALL. Finally, our study also shows that HSP90 inhibitors are potent against ruxolitinibresistant variants through the JAK2 degradation and provides the rationale for clinical evaluation of potent HSP90 inhibitors in genetic resistance driven by JAK2 inhibitors. Conclusion: Our study identifies JAK1 and JAK2 resistance variants against the type I JAK2 inhibitors ruxolitinib, fedratinib, and lestaurtinib. The sensitivity of these resistant variants towards the type II JAK2 inhibitor CHZ-868 indicates that this mode of type II JAK2 inhibition is a potential therapeutic approach against ruxolitinib refractory leukemia. This also proposes the development of potent and specific type II JAK2 inhibitors using ruxolitinib-resistance variants as a prototype. [ABSTRACT FROM AUTHOR]