[The Effect of Ruxolitinib on the Expression of VEGF and HIF-1α in Leukemia HEL Cells]

OBJECTIVES

To investigate the effect of Ruxolitinib on the expression of vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1 α (HIF-1α) in HEL cells.

METHODS

he HEL cells were treated with Ruxolitinib in different concentrations (1 nmol/L, 5 nmol/L, 10 nmol/L, 50 nmol/L, 100 nmol/L, 500 nmol/L). The growth inhibition of Ruxolitinib on HEL cells was detected by CCK-8 assay;the mRNA expression level ofJAK2 were measured by RT-PCR and the protein level of p-JAK2, VEGF, HIF-1α were observed by Western blot after treated with Ruxolitinib for 24,48,72 h. Chick chorioallantoic membrane (CAM) test was used to testify the effect of Ruxolitinib on angiogenesis.

RESULTS

Ruxolitinib with different concentrations could inhibit HEL cells proliferation. RT-PCR showed that the mRNA level ofJAK2 decreased in a concentration-dependent manner and Western blot demonstrated that the expression levels of p-JAK2, VEGF and HIF-1α were lower in Ruxolitinib treatment groups than those in control group (P<0.05) after HEL cells were treated with different concentrations of Ruxolitinib for 24,48,72 h. Ruxolitinib significantly suppressed blood vessels'formation in CAM.

CONCLUSIONS

Ruxolitinib can inhibit VEGF, HIF-1α expression and angiogenesis of HEL leukemia cells by inhibiting JAK2 pathway.

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.

In-Hospital and readmission outcomes of patients with myeloproliferative neoplasms and atrial fibrillation: insights from the National Readmissions Database

INTRODUCTION

Patients with myeloproliferative neoplasms (MPNs) and atrial fibrillation (AF) are at increased risk of thrombosis and bleeding. However, the risk of thrombosis and bleeding in patients with AF and MPN compared with the general population with AF is unclear. Additionally, traditional risk scores (CHA2DS2-VASC and HAS-BLED) for risk/benefit estimation of thromboprophylaxis in AF do not account for MPN status. Therefore, we aimed to investigate bleeding and thrombosis risk in patients with MPN hospitalized for AF.

METHODS

We utilized the National Readmission Database (NRD) to identify patients with AF with and without MPN. Primary bleeding and thrombosis outcomes were in-hospital or 30-day readmission for bleeding or thrombosis, respectively. We propensity score (PS) matched patients with and without MPN. Risk of primary outcomes in MPN was assessed in PS matched cohort using logistic regression. Receiver operating characteristic (ROC) curve used to evaluate predictive ability of CHA2DS2-VASC and HAS-BLED of primary thrombosis and bleeding outcomes, respectively.

RESULTS

24,185 patients without MPN were matched with 1,617 patients with MPN and variables were balanced between groups. Patients with MPN were at increased risk of meeting the thrombosis (OR 1.98, 95% CI 1.23-3.21) but not bleeding (OR 0.87, 95% CI 0.63-1.19) primary outcomes. In MPN, CHA2DS2-VASC predicted thrombosis (C-statistic 0.66, 95% CI 0.54-0.78) but HAS-BLED was a poor predictor of bleeding (C-statistic 0.55, 95% CI 0.46-0.64).

CONCLUSION

In patients with AF, MPN was associated with increased risk of bleeding and thrombosis. HAS-BLED scores did not accurately predict bleeding in MPN. Further investigation is needed to refine risk scores in MPN.

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.

JAK2 p.(V617F) mutation in Tunisian myeloproliferative neoplasms and its genotype-phenotype correlation

Myeloproliferative neoplasms (MPNs) comprise polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). The relationship between JAK2 p.(V617F) mutation and MPNs was first described in 2005. The purpose of this study was to determine the prevalence of JAK2 p.(V617F) mutation in Tunisian patients assessed for MPNs and try to set a genotype-phenotype correlation. A retrospective study was conducted between January 2015 and April 2019. We collected the clinical data of all patients with MPNs suspicion or atypical splanchnic vein thrombosis (SVT). JAK2 p.(V617F) mutation was detected by allele specific real-time quantitative fluorescence PCR (AS-qPCR). We gathered 974 patients who underwent molecular analysis, 55.5% of them were male and 44.5% were female. The median age of all studied patients was 56 years. JAK2 p.(V617F) was found in 349 (35.8%) of total enrolled cases. It was reported in 44%, 37%, 29% and 25% of all patients diagnosed as having respectively ET, PV, PMF and atypical SVT. JAK2 p.(V617F) was negative in 62.2% of patients addressed for suspicion of PV. There was a significant positive correlation between the JAK2 p.(V617F) mutation status, age, gender, white blood cell counts and platelet counts. To our best knowledge, this is the first vast investigation of JAK2 p.(V617F) variant in Tunisia and North Africa with the lowest mutation rate in entire cohort and MPNs subgroups, underlying a specific presentation of this mutation. It is considered as an essential marker of MPNs’ diagnosis and prognosis and is associated with differences in the phenotype of these disorders, helpful for the follow-up of these patients.

Treatment With JAK Inhibitors in Myelofibrosis Patients Nullifies the Prognostic Impact of Unfavorable Cytogenetics

INTRODUCTION

In the era before Janus kinase (JAK) inhibitors, cytogenetic information was used to predict survival in myelofibrosis patients. However, the prognostic value of cytogenetics in the setting of JAK inhibitor therapy remains unknown.

PATIENTS AND METHODS

We performed a retrospective analysis of 180 patients with bone marrow biopsy-proven myelofibrosis from 3 US academic medical centers. We fit Cox proportional hazards models for overall survival and transformation-free survival on the bases of 3 factors: JAK inhibitor therapy as a time-dependent covariate, dichotomized cytogenetic status (favorable vs. unfavorable), and statistical interaction between the two. The median follow-up time was 37.1 months.

RESULTS

Among patients treated with best available therapy, unfavorable cytogenetic status was associated with decreased survival (hazard ratio = 2.31; P = .025). At initiation of JAK inhibitor therapy, unfavorable cytogenetics was (nonsignificantly) associated with increased survival compared to favorable cytogenetics (hazard ratio = 0.292; P = .172). The ratio of hazard ratios was 0.126 (P = .034). These findings were similar after adjusting for standard clinical prognostic factors as well as when measured against transformation-free survival.

CONCLUSION

The initiation of JAK inhibitor therapy appears to change the association between cytogenetics and overall survival. There was little difference in survival between treatment types in patients with favorable cytogenetics. However, the use of JAK inhibitor therapy among patients with unfavorable cytogenetics was not associated with worse survival compared to favorable cytogenetics. Our analyses suggest that initiation of JAK inhibitor therapy nullifies the negative prognostic implication of unfavorable cytogenetics established in the pre-JAK inhibitor therapy era.

Transcriptional configurations of myeloproliferative neoplasms

Myeloproliferative neoplasms (MPNs) is an umbrella term for several heterogenous diseases, which are characterized by their stem cell origin, clonal hematopoiesis and increase of blood cells of the myeloid lineage. The focus will be on BCR-ABL1 negative MPNs, polycythemia vera (PV), primary myelofibrosis (PMF), essential thrombocythemia (ET). Seminal findings in the field of MPN were driven by genomic analysis, focusing on dissecting genomic changes MPN patients. This led to identification of major MPN driver genes, JAK2, MPL and CALR. Transcriptomic analysis promises to bridge the gap between genetic and phenotypic characterization of each patient's tumor and with the advent of single cell sequencing even for each MPN cancer cell. This review will focus on efforts to mine the bulk transcriptome of MPN patients, including analysis of fusion genes and splicing alterations which can be addressed with RNA-seq technologies. Furthermore, this paper aims to review recent endeavors to elucidate tumor heterogeneity in MPN hematopoietic stem and progenitor cells using single cell technologies. Finally, it will highlight current shortcoming and future applications to advance the field in MPN biology and improve patient diagnostics using RNA-based assays.

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.

Real-life use of ropeg-interferon α2b in polycythemia vera: patient selection and clinical outcomes

Ropeginterferon-alfa2b (ropegIFNα2b) is a long-acting IFN formulation with broad FDA/EMA approval as a therapy of polycythemia vera (PV) with no symptomatic splenomegaly. There is currently lack of information on the real-world patient selection, including the impact of local reimbursement policies, and drug management, particularly: type/timing of screening and follow-up tests; absolute/relative contraindications to therapy; ropegIFNα2b dose and combinations with hydroxyurea. As a sub-analysis of the PV-ARC retrospective study (NCT06134102), we here report our monocenter experience with ropegIFNα2b in the period from January 2021, corresponding to drug availability outside clinical trial, and December 2023. Among the 149 patients with EMA/FDA indication, only 55 (36.9%) met the local reimbursement criteria and 18 (12.1%) received ropegIFNα2b. Thanks to appropriate screening, relative/absolute contraindications to ropegIFNα2b were detected and managed in a multidisciplinary manner. Efficacy and safety of ropegIFNα2b was confirmed, with 3 cases of early molecular response. General use of low ropegIFNα2b dose, with frequent need for hydroxyurea combinations, was noted. This real-world experience suggests a significant impact of local regulations on drug prescription and the need for greater real-world data collection on ropegIFNα2b in PV patients. Also, it describes appropriate multidisciplinary screening and monitoring procedures during ropegIFNα2b therapy.

[Systemic pruritus: what is new in diagnosis and treatment?]

BACKGROUND

Chronic pruritus is a common symptom of various systemic diseases. In particular, patients with chronic renal failure, hepatobiliary diseases, and myeloproliferative neoplasms are affected.

OBJECTIVES

The purpose of this review is to provide an overview of laboratory chemistry and imaging diagnostics as well as current and novel therapeutic approaches to pruritus of systemic diseases.

MATERIALS AND METHODS

An extensive PubMed search was performed.

RESULTS

To clarify the cause of chronic pruritus, a step-by-step diagnosis is recommended, which is based on the frequency of pruritus-associated diseases. A basic diagnosis enables a cost-effective and targeted clarification at the level of a general practitioner. Current topical and drug therapy recommendations of pruritus in chronic renal failure, hepatobiliary diseases, myeloproliferative neoplasms, and rarer causes are summarized. In addition, novel therapeutic approaches such as the κ‑opioid receptor agonist difelikefalin, bezafibrate, inhibitors of the ileal bile acid transporter (IBAT), and the JAK-STAT pathway are highlighted.

CONCLUSIONS

Chronic pruritus in systemic diseases can be a diagnostic challenge. A staged diagnostic approach facilitates identification of the underlying disease. Improved pathophysiological understanding has led to the first approved therapeutic options for chronic kidney disease-associated and hepatic pruritus.

Pacritinib prevents inflammation-driven myelofibrosis-like phenotype in a miR-146a-/- murine model

Chronic proinflammatory signaling is a characteristic trait in myeloproliferative neoplasms (MPN), particularly myelofibrosis (MF). Aberrant inflammatory signaling, particularly from NF-κB pathway, exacerbates the progression of MPN. Previously, we identified a critical role of miR-146a, a negative regulator of the TLR/NF-κB axis, in MF development. MPN patients carrying the miR-146a rs2431697-TT genotype, associated with lower miR-146a expression levels, have a higher risk of progression to overt-MF from chronic-phase disease. Using miR-146a-/- (KO) mice, a MF-like model lacking MPN driver mutations, we here investigate whether pacritinib, a dual JAK/NF-κB pathways inhibitor (via JAK2/IRAK1, respectively), prevents the age-associated myelofibrotic phenotype of these mice. Young miR-146a-/- mice were treated either with or without pacritinib, for 3 or 6 months. Notably, pacritinib prevented the splenomegaly, reticulin fibrosis and osteosclerosis observed in untreated KO mice. Pacritinib also avoided the myeloproliferation, loss of splenic architecture, and extramedullary hematopoiesis observed in age-matched untreated KO mice. Pharmacological targeting of IRAK1/JAK2 attenuated the pro-inflammatory environment, preventing the increase of inflammatory cytokines, particularly CXCL1 and TNF-α, without inducing cytopenias but rather the opposite. Compared to age-matched untreated KO mice, treated mice showed higher platelet counts irrespective of treatment duration, and higher erythrocyte counts with the longer treatment. Additionally, pacritinib preventive treatment reduced COL1A1 production in an in vitro model mimicking JAK2-driven fibrosis. These findings highlight that dual inhibition of JAK2/IRAK1 with pacritinib, by delaying or attenuating the myelofibrotic progression, could be a potential modifier of the natural course of MPN.

DARS expression in BCR/ABL1-negative myeloproliferative neoplasms and its association with the immune microenvironment

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 < 0.05). Notably, elevated DARS expression was linked to splenomegaly in MPNs patients. The expression of DARS showed a negative correlation with CD4+ T cells (R = - 0.451, P = 0.0004) and CD4+ T/CD8+ T cell ratio (R = - 0.3758, P = 0.0040), as well as with CD68+ tumor-associated macrophages (R = 0.4037, P = 0.0017). Conversely, it was positively correlated with IL-2 (R = 0.5419, P < 0.001), IL-5 (R = 0.3161, P = 0.0166), IL-6 (R = 0.2992, P = 0.0238), and IFN-γ (R = 0.3873, P = 0.0029). These findings underscore a significant association between DARS expression in MPNs patients and specific clinical characteristics, as well as immune cell composition. Further investigation into the interplay between DARS and the immune microenvironment in MPNs could shed light on the underlying mechanisms of MPNs pathogenesis and immune dysregulation.

Recent advances in therapies for primary myelofibrosis

Primary myelofibrosis (PMF), polycythemia vera (PV) and essential thrombocythemia (ET) form the classical BCR-ABL1-negative myeloproliferative neoplasms (MPNs) that are driven by a constitutive activation of JAK2 signaling. PMF as well as secondary MF (post-ET and post-PV MF) are the most aggressive MPNs. Presently, there is no curative treatment, except allogenic hematopoietic stem cell transplantation. JAK inhibitors, essentially ruxolitinib, are the therapy of reference for intermediate and high-risk MF. However, presently the current JAK inhibitors behave mainly as anti-inflammatory drugs, improving general symptoms and spleen size without major impact on disease progression. A better understanding of the genetics of MF, the biology of its leukemic stem cells (LSCs), the mechanisms of fibrosis and of cytopenia and the role of inflammatory cytokines has led to new approaches with the development of numerous therapeutic agents that target epigenetic regulation, telomerase, apoptosis, cell cycle, cytokines and signaling. Furthermore, the use of a new less toxic form of interferon-α has been revived, as it is presently one of the only molecules that targets the mutated clone. These new approaches have different aims: (a) to provide alternative therapy to JAK inhibition; (b) to correct cytopenia; and (c) to inhibit fibrosis development. However, the main important goal is to find new disease modifier treatments, which will profoundly modify the progression of the disease without major toxicity. Presently the most promising approaches consist of the inhibition of telomerase and the combination of JAK2 inhibitors (ruxolitinib) with either a BCL2/BCL-xL or BET inhibitor. Yet, the most straightforward future approaches can be considered to be the development of and/or selective inhibition of JAK2V617F and the targeting MPL and calreticulin mutants by immunotherapy. It can be expected that the therapy of MF will be significantly improved in the coming years.

Development of a Real-Time qPCR Assay for Detection of Common MPL Mutations in Myeloproliferative Neoplasms (MPNS)

Myeloproliferative neoplasms (MPNs) are blood cell disorders, characterized by overproduction of abnormal cells in bone marrow due to stem cell mutation. The proliferations of blood cell are controlled by many genes particularly MPL gene which encodes thrombopoietin receptor, a hematopoietic growth factor involved in the production and regulation of the platelets and multipotent hematopoietic progenitor cells. Acquired mutations including (W515L and W515K) in this gene have been observed in patients with primary myelofibrosis or essential thrombocythemia lacking JAK2 (V617F) mutations. MPL mutation detection is important for MPNs diagnosis, but due to low frequency of mutant allele burden (< 15%) may be missed by already available common assays such as Sanger sequencing. Furthermore, these techniques are costly, time-consuming, and less sensitive. In present study, we aimed to develop sensitive, less time-consuming, and cost-effective real-time PCR assay for the detection of MPL mutations that is based on TaqMan fluorescent probes. DNA was extracted from blood sample of 128 MPNs patients collected and further analysis was performed on TaqMan RT-PCR. Reference curve was obtained for amplified product of MPL gene containing mutated sequence. The predicted sensitivity level was at least 5% mutant allele burden by our developed assay that is much higher than sequencing output. Out of 128, 2 (1.56%) patients harbored W515L mutation and 1 (0.78%) harbored W515K mutation. It was concluded that TaqMan qRT-PCR assay is an efficient, sensitive, cost-effective, and less time-consuming method capable of detecting MPL mutation in MPNs patients. We suggested that this assay might be helpful in investigating mutant allele load in MPNs patients.

Variability of bone marrow biopsy reporting affects accuracy of diagnosis of myeloproliferative neoplasms: data from the ALLG MPN01 registry

The Philadelphia-negative myeloproliferative neoplasms (MPN) are a heterogeneous group of overlapping bone marrow disorders defined by characteristic peripheral blood counts and bone marrow morphological findings in conjunction with recurrent somatic mutations. The accurate diagnosis and subclassification of MPN relies upon careful reporting of bone marrow morphology combined with ancillary information in an integrated pathology report. This co-operative trial group study ALLG MPN01 (ANZCTR:12613000138785), led by the Australasian Leukaemia & Lymphoma Group (ALLG), aimed to describe the current approach to diagnosis of MPN in routine practice. Specifically, we assessed the frequency with which bone marrow biopsies were performed, and the adherence of reporting pathologists to recommendations contained in the revised 2016 WHO classification pertaining to MPN. We reviewed the diagnosis of 152 patients from eight institutions who were enrolled in a national MPN registry of the ALLG between 2010 and 2016. The ALLG MPN01 registry is now closed to recruitment. Key features were extracted from pathology reports provided to the registry. Bone marrow biopsies were performed in 112/152 cases (74%). The pathological information entered was concordant with the stated clinical diagnosis in 75/112 cases (67%). The main reasons for discordant results were incomplete descriptions of megakaryocyte topography and morphology, inconsistent grading of reticulin fibrosis, and failure to integrate the available morphological and ancillary clinicopathological information. In this retrospective audit, 26% of MPN patients did not undergo a diagnostic bone marrow biopsy. In those who did, the specific MPN subtype may not have been reported correctly in 33% of cases, as evidenced by inconsistent features reported or insufficient information to assess. A more standardised approach to bone marrow reporting is required to ensure accuracy of MPN diagnoses and consistent reporting to cancer registries and clinical trials.

The aetiology and burden of myeloproliferative neoplasms in the United Kingdom: the MyelOproliferative neoplasmS: an In-depth case-control (MOSAICC) study protocol

BACKGROUND

Myeloproliferative neoplasms (MPNs) are a group of haematological malignancies that affect approximately 8 people in every 100,000 individuals in the UK. Little is known about the aetiology of MPNs, as previous studies have been hampered by small sample sizes, thus it is important to understand the cause of MPNs in a larger study to identify prevention strategies and improve treatment strategies. This study aims to determine environmental, lifestyle, genetic and medical causes of MPNs and to assess the relevance of occupational carcinogen exposures and quality of life impacts.

METHODS

A UK-wide case-control study of 610 recently diagnosed MPN patients (within 24 months) receiving clinical care at 21 NHS study sites in Scotland, England, Wales and Northern Ireland and 610 non-blood relative/friend controls is underway. Data on occupational and residential history, medical and environmental factors, and quality of life are being collected from the participants via a structured interview and self-complete questionnaires. Clinical data is being provided by the clinical team. Blood, saliva and toenail samples are also being collected for genetic and elemental analysis. Adjusted odds ratios (ORs) and 95% confidence intervals (95%CI) will be calculated using a p < 0.05 to investigate potential risk factors for the MPN clinical and genetic subtypes, and further analyses will be conducted based on the type of data and outcome of interest at a later stage.

DISCUSSION

The study design is most effective for investigating the aetiology of rare diseases. The study will enable identification of potential causes of MPNs through in-depth assessment of potential risk factors with potential for longer follow-up of a number of outcomes.

Analysis of real-world data demonstrating the efficacy of current management of polycythaemia vera in attaining and maintaining therapeutic haematocrit

BACKGROUND

Polycythaemia vera (PV) is a Philadelphia-negative myeloproliferative neoplasm, typically driven by acquired JAK2 mutation and characterised by elevated red cell mass and increased risk of thrombotic events. Patients are managed with phlebotomy to maintain haematocrit (Hct) < 0.45, and patients stratified as 'high risk' for thrombosis are additionally treated with cytoreductive agents to attain this target.

STUDY

This analysis of newly diagnosed JAK2 mutant PV patients (n = 50) over 2 years aimed to determine how effectively patients attained and maintained target Hct according to recommended practice.

CONCLUSIONS

We found that patients spent the majority of time in target Hct range. Findings are supportive of current management guidelines.

Clinico-Pathological Profile And Outcomes Of Patients With Polycythaemia Vera, Essential Thrombocythaemia And Idiopathic Myelofibrosis: A Tertiary Care Center Experience From Southern Pakistan

BACKGROUND

The "Philadelphia Negative Classic Myeloproliferative Neoplasms" include polycythaemia vera (PV), essential thrombocythaemia (ET) and idiopathic myelofibrosis (IMF). These three disorders share several clinical and laboratory features including JAK2 V617F mutation. Our objectives were to determine the clinico-pathological profile and outcomes of Pakistani patients with polycythaemia vera (PV), essential thrombocythaemia (ET) and idiopathic myelofibrosis (IMF) in order to have an insight regarding behaviour of these conditions.

METHODS

A retrospective analysis of all the cases of PV, ET and IMF diagnosed at our institute from January 1995 to December 2013 was performed. Age, gender, clinical presentation, laboratory investigations, treatment provided and duration of follow-up were included for analysis. Appropriate statistics were utilized for calculation of data.

RESULTS

A total of 58 patients were diagnosed as PV, ET or IMF during the study period. Male to female ratio was 1.1:1. Forty five percent (n=27) patients came to medical attention due to abnormal laboratory results, 3 had cerebrovascular events, 3 had pruritus, and 1 patient each with gangrene and Budd-Chiari syndrome. Haemorrhage was not seen in any patient. Sixty percent (n=35) patients were treated with phlebotomy, hydroxyurea and aspirin alone or in combination. None of the patients transformed to myelofibrosis (MF) or myelodysplasia (MDS) during the mean (±SD) follow-up period of 57.2±50 months. One patient with ET transformed to acute myeloid leukaemia 9 years after the diagnosis.

CONCLUSIONS

This study demonstrated a relatively more benign form of PV, ET and IMF with lesser frequency of symptoms, good response to treatment and less likelihood of transformation to MF, MDS or AML.

[Perspectives on a new therapeutic approach for myeloproliferative neoplasms]

After the discovery of driver mutations for myeloproliferative neoplasms (MPN), treatment approach for the disease has achieved tremendous progress. Ruxolitinib, a JAK inhibitor, is now widely used for both patients with myelofibrosis and polycythemia vera in several countries, including Japan. Fedratinib, another JAK inhibitor, has been recently approved in the United States. One of the biggest limitations of treatment with JAK inhibitors is the relatively small proportion of patients who achieve a complete molecular response. Furthermore, most of the patients with myelofibrosis had to discontinue the treatment due to drug-related adverse events or disease progression. Therefore, MPN treatment is still at an early and challenging stage, thereby highlighting the urgent need for establishment of a new and more effective therapeutic strategy. One of the promising candidates for MPN treatment is the use of interferons. Modern forms of interferons demonstrate not only a good hematological response but also a deep molecular response, eradicating abnormal MPN clones harboring driver mutations. A number of new agents targeting molecules outside of the JAK-STAT pathway, PI3kinase, NF-kB, or Bcl-2 family of anti-apoptotic proteins are also being considered and tested in clinical studies as single-agent therapies or in combination with JAK inhibitors.

[Idiopathic esophageal submucosal hematoma during antithrombotic therapy for essential thrombocythemia]

A 73-year-old woman was hospitalized with sudden chest pain and hematemesis. Chest computed tomography and upper gastrointestinal endoscopy revealed an idiopathic submucosal hematoma from the cervical esophagus to the esophagogastric mucosal junction. Idiopathic esophageal submucosal hematoma is often prone to a bleeding tendency of an underlying disorder. The patient had a history of essential thrombocythemia (ET) and was taking aspirin. She successfully recovered after aspirin discontinuation and conservative treatment; however, died of cardiopulmonary arrest in the ward on day 9 of hospitalization. The autopsy revealed that the cause of death was pulmonary thromboembolism. This is the first report of ET with submucosal hematoma of the esophagus. The possibility of an esophageal submucosal hematoma should be considered when patients with ET complain of chest pain since ET and treatment with aspirin are considered risk factors for bleeding. Additionally, close attention should be focused on the risk of developing thrombosis if a patient with myeloproliferative neoplasm is required to discontinue antithrombotic therapy due to a bleeding event.

Polycythemia vera

Polycythemia vera (PV) is mainly characterized by erythrocytosis, thrombotic and hemorrhagic predisposition, a variety of symptoms, and cumulative risks of fibrotic progression and/or leukemic evolution over time. The diagnosis is made based on the 2016 WHO criteria. The treatment of PV focuses on rapidly reducing the erythrocyte mass, either by means of phlebotomies or with cytoreductive treatment, and the reduction of thrombotic risk by correcting cardiovascular risk factors and the use of platelet antiaggregants.

[Clinical and genetic characteristics of young patients with myeloproliferative neoplasms]

Objectives: To investigate the clinical and genetic features of young Chinese patients with myeloproliferative neoplasms (MPN). Methods: In this cross-sectional study, anonymous questionnaires were distributed to patients with MPN patients nationwide. The respondents were divided into 3 groups based on their age at diagnosis: young (≤40 years) , middle-aged (41-60 years) , and elderly (>60 years) . We compared the clinical and genetic characteristics of three groups of MPN patients. Results: 1727 assessable questionnaires were collected. There were 453 (26.2%) young respondents with MPNs, including 274 with essential thrombocythemia (ET) , 80 with polycythemia vera (PV) , and 99 with myelofibrosis. Among the young group, 178 (39.3%) were male, and the median age was 31 (18-40) years. In comparison to middle-aged and elderly respondents, young respondents with MPN were more likely to present with a higher proportion of unmarried status (all P<0.001) , a higher education level (all P<0.001) , less comorbidity (ies) , fewer medications (all P<0.001) , and low-risk stratification (all P<0.001) . Younger respondents experienced headache (ET, P<0.001; PV, P=0.007; MF, P=0.001) at diagnosis, had splenomegaly at diagnosis (PV, P<0.001) , and survey (ET, P=0.052; PV, P=0.063) . Younger respondents had fewer thrombotic events at diagnosis (ET, P<0.001; PV, P=0.011) and during the survey (ET, P<0.001; PV, P=0.003) . JAK2 mutations were found in fewer young people (ET, P<0.001; PV, P<0.001; MF, P=0.013) ; however, CALR mutations were found in more young people (ET, P<0.001; MF, P=0.015) . Furthermore, mutations in non-driver genes (ET, P=0.042; PV, P=0.043; MF, P=0.004) and high-molecular risk mutations (ET, P=0.024; PV, P=0.023; MF, P=0.001) were found in fewer young respondents. Conclusion: Compared with middle-aged and elderly patients, young patients with MPN had unique clinical and genetic characteristics.

[Myelofibrosis: A review]

Myelofibrosis is a BCR-ABL1-negative chronic myeloproliferative neoplasm that includes primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. It is characterized by stem cell-derived clonal proliferation that is often, but not always, accompanied by somatic mutations, which are classified into driver mutations (JAK2, CALR, or MPL), subclonal mutations and fibrosis on bone marrow biopsy. Myelofibrosis commonly demonstrates splenomegaly, constitutional symptoms, anemia, thrombocytosis, or thrombocytopenia. Patients may also be asymptomatic. Complications as thromboembolic or hemorrhagic events can reveal the disease. Primary myelofibrosis is the least common myeloproliferative neoplasm but is associated with poor survival and acute leukemic transformation. In contrast to the significant progress made in understanding the disease's pathogenesis, treatment for myelofibrosis remains largely palliative. The JAK2 inhibitor, ruxolitinib is not sufficient in eliminating the underlying myeloid progenitor clone, as disease inevitably returns with therapy discontinuation. Allogeneic hematopoietic stem cell transplantation is the only therapeutic option that offers potential cure. The development of novel treatment strategies aimed at slowing or even reversing disease progression, prolonging patient survival and preventing evolution to blast-phase are still lacking.

[The genetic characteristics of BCR-ABL-negative myeloproliferative neoplasms]

Objective: To explore the relationship between driver gene mutation (JAK2, MPL and CALR) and disease type in BCR-ABL negative myeloproliferative neoplasms (MPNs) including primary myeloid fibrosis (PMF), essential thrombocytosis (ET) and polycythemia vera (PV). Methods: A total of 32 MPN related genes were detected by high-throughput sequencing in 156 MPN patients. The relationships between disease type and patients' general performance, the characteristics of driver gene mutations, concomitant gene mutations were analyzed. Results: In the population with JAK2 V617F positive mutation, the proportion of patients over 60 years old in PMF was higher than that with ET or PV. By high-throughput sequencing, 22 concomitant gene mutations were detected in 46 patients with JAK2, MPL or CALR mutations, including 4 (8.3%) in PV, 20 (29.4%) in ET, and 22 (55.0%) in PMF. DNMT3A mutation was detected only in patients with PV, while splicing factor related genes including SF3B1, SRSF2 and U2AF1 were only accompanied by PMF. According to the variation allele frequency (VAF) value of JAK2 V617F mutation, the VAF value associated with PV was the highest (68.15%), followed by PMF (37.7%) and ET (23%). However, there were significant differences in the incidence of JAK2 V617F homozygous among 3 different diseases. In patients with JAK2 mutation, the proportion of other gene mutations in PV and ET was significantly lower than that in PMF. Conclusions: Under the condition of common driver gene mutations (JAK2, MPL and CALR), patients' age, VAF value and homozygous state, concomitant gene mutations are closely related to different disease type. These correlations help to improve clinical understanding of disease characteristics and risk assessment.

Efficacy and safety of combination therapies vs monotherapy of hypomethylating agents in accelerated or blast phase of Philadelphia negative myeloproliferative neoplasms: a systematic review and meta-analysis

BACKGROUND

There is a lack of evidence regarding whether combination therapy of hypomethylating agents (HMAs) has better outcomes than HMA monotherapy in patients with Philadelphia chromosome-negative accelerated or blast phase myeloproliferative neoplasms (MPN-AP/BP).

MATERIALS AND METHODS

Pubmed, Embase, Web of Science and Cochrane library databases were searched for studies from inception of each database until 31 December 2021. Data extraction and synthesis were conducted following the PRISMA reporting guideline.

RESULTS

It was found that HMAs plus venetoclax therapy yielded a higher CR/CRi rate than HMAs alone [36% vs 19%, p = .0204] and a higher CR rate than HMAs plus ruxolitinib [22% vs 8%, p = .0313]. HMAs plus ruxolitinib combination showed a higher ORR than HMA monotherapy [45% vs 30%, p = .0395], but there was no improvement in CR/CRi. The one-year and two-year OS rate for patients treated with HMAs plus venetoclx/ruxolitinib demonstrated a trend towards prolonged survival than HMAs alone [HMAs plus venetoclax: 24% vs 11%, p = .1295 and 12% vs 3%, p = .2357; HMAs plus ruxolitinib: 25% vs 11%, p = .0774 and 33% vs 3%, p = .051].

CONCLUSION

It was confirmed that HMA in combination with venetoclax is an effective and well-tolerated option in MPN-AP/BP patients in pre- as well as post-haematopoietic stem cell transplantation settings. HMA plus ruxolitinib therapy was revealed to be effective in patients with MPN-AP.Key MessagesCombination therapy with HMAs and venetoclax/ruxolitinib was associated with improved outcomes than HMAs alone in MPN-AP/BP patients.Further large-scale randomized controlled trials are needed to confirm regarding to the optimal treatment for this patient population.