Explore the vast range of titles available.

The leucocyte common antigen, protein tyrosine phosphatase receptor type C (PTPRC), also known as CD45, is a transmembrane glycoprotein, expressed on almost all haematopoietic cells except for mature erythrocytes, and is an essential regulator of T and B cell antigen receptor-mediated activation. Disruption of the equilibrium between protein tyrosine kinase and phosphatase activity (from CD45 and others) can result in immunodeficiency, autoimmunity, or malignancy. CD45 is normally present on the cell surface, therefore it works upstream of a large signalling network which differs between cell types, and thus the effects of CD45 on these cells are also different. However, it is becoming clear that CD45 plays an essential role in the innate immune system and this is likely to be a key area for future research. In this review of PTPRC (CD45), its structure and biological activities as well as abnormal expression of CD45 in leukaemia and lymphoma will be discussed.

The Philadelphia negative myeloproliferative neoplasms (MPN) compromise a heterogeneous group of clonal myeloid stem cell disorders comprising polycythaemia vera, essential thrombocythaemia and primary myelofibrosis. Despite distinct clinical entities, these disorders are linked by morphological similarities and propensity to thrombotic complications and leukaemic transformation. Current therapeutic options are limited in disease-modifying activity with a focus on the prevention of thrombus formation. Constitutive activation of the JAK/STAT signalling pathway is a hallmark of pathogenesis across the disease spectrum with driving mutations in JAK2 , CALR and MPL identified in the majority of patients. Co-occurring somatic mutations in genes associated with epigenetic regulation, transcriptional control and splicing of RNA are variably but recurrently identified across the MPN disease spectrum, whilst epigenetic contributors to disease are increasingly recognised. The prognostic implications of one MPN diagnosis may significantly limit life expectancy, whilst another may have limited impact depending on the disease phenotype, genotype and other external factors. The genetic and clinical similarities and differences in these disorders have provided a unique opportunity to understand the relative contributions to MPN, myeloid and cancer biology generally from specific genetic and epigenetic changes. This review provides a comprehensive overview of the molecular pathophysiology of MPN exploring the role of driver mutations, co-occurring mutations, dysregulation of intrinsic cell signalling, epigenetic regulation and genetic predisposing factors highlighting important areas for future consideration.

The aim of this literature review is to examine the significance of the nucleophosmin 1 (NPM1) gene in acute myeloid leukaemia (AML). This will include analysis of the structure and normal cellular function of NPM1, the type of mutations commonly witnessed in NPM1, and the mechanism by which this influences the development and progression of AML. The importance of NPM1 mutation on prognosis and the treatment options available to patients will also be reviewed along with current guidelines recommending the rapid return of NPM1 mutational screening results and the importance of employing a suitable laboratory assay to achieve this. Finally, future developments in the field including research into new therapies targeting NPM1 mutated AML are considered.

The myeloproliferative neoplasms (MPN), polycythaemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF) are linked by a propensity to thrombosis formation and a risk of leukaemic transformation. Activation of cytokine independent signalling through the JAK/STAT cascade is a feature of these disorders. A point mutation in exon 14 of the JAK2 gene resulting in the formation of the JAK2 V617F transcript occurs in 95% of PV patients and around 50% of ET and PMF patients driving constitutive activation of the JAK/STAT pathway. Mutations in CALR or MPL are present as driving mutations in the majority of remaining ET and PMF patients. Ruxolitinib is a tyrosine kinase inhibitor which inhibits JAK1 and JAK2. It is approved for use in intermediate and high risk PMF, and in PV patients who are resistant or intolerant to hydroxycarbamide. In randomised controlled trials it has demonstrated efficacy in spleen volume reduction and symptom burden reduction with a moderate improvement in overall survival in PMF. In PV, there is demonstrated benefit in haematocrit control and spleen volume. Despite these benefits, there is limited impact to induce complete haematological remission with normalisation of blood counts, reduce the mutant allele burden or reverse bone marrow fibrosis. Clonal evolution has been observed on ruxolitinib therapy and transformation to acute leukaemia can still occur. This review will concentrate on understanding the clinical and molecular effects of ruxolitinib in MPN. We will focus on understanding the limitations of JAK inhibition and the challenges to improving therapeutic efficacy in these disorders. We will explore the demonstrated benefits and disadvantages of ruxolitinib in the clinic, the role of genomic and clonal variability in pathogenesis and response to JAK inhibition, epigenetic changes which impact on response to therapy, the role of DNA damage and the role of inflammation in these disorders. Finally, we will summarise the future prospects for improving therapy in MPN in the JAK inhibition era.

Acute promyelocytic leukaemia is a chemotherapy-sensitive subgroup of acute myeloid leukaemia characterised by the presence of the PML–RARA fusion transcript. The present standard of care, chemotherapy and all-trans retinoic acid (ATRA), results in a high proportion of patients being cured. In this study, we compare a chemotherapy-free ATRA and arsenic trioxide treatment regimen with the standard chemotherapy-based regimen (ATRA and idarubicin) in both high-risk and low-risk patients with acute promyelocytic leukaemia. In the randomised, controlled, multicentre, AML17 trial, eligible patients (aged ≥16 years) with acute promyelocytic leukaemia, confirmed by the presence of the PML–RARA transcript and without significant cardiac or pulmonary comorbidities or active malignancy, and who were not pregnant or breastfeeding, were enrolled from 81 UK hospitals and randomised 1:1 to receive treatment with ATRA and arsenic trioxide or ATRA and idarubicin. ATRA was given to participants in both groups in a daily divided oral dose of 45 mg/m2 until remission, or until day 60, and then in a 2 weeks on–2 weeks off schedule. In the ATRA and idarubicin group, idarubicin was given intravenously at 12 mg/m2 on days 2, 4, 6, and 8 of course 1, and then at 5 mg/m2 on days 1–4 of course 2; mitoxantrone at 10 mg/m2 on days 1–4 of course 3, and idarubicin at 12 mg/m2 on day 1 of the final (fourth) course. In the ATRA and arsenic trioxide group, arsenic trioxide was given intravenously at 0·3 mg/kg on days 1–5 of each course, and at 0·25 mg/kg twice weekly in weeks 2–8 of course 1 and weeks 2–4 of courses 2–5. High-risk patients (those presenting with a white blood cell count >10 × 109 cells per L) could receive an initial dose of the immunoconjugate gemtuzumab ozogamicin (6 mg/m2 intravenously). Neither maintenance treatment nor CNS prophylaxis was given to patients in either group. All patients were monitored by real-time quantitative PCR. Allocation was by central computer minimisation, stratified by age, performance status, and de-novo versus secondary disease. The primary endpoint was quality of life on the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-C30 global health status. All analyses are by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN55675535. Between May 8, 2009, and Oct 3, 2013, 235 patients were enrolled and randomly assigned to ATRA and idarubicin (n=119) or ATRA and arsenic trioxide (n=116). Participants had a median age of 47 years (range 16–77; IQR 33–58) and included 57 high-risk patients. Quality of life did not differ significantly between the treatment groups (EORTC QLQ-C30 global functioning effect size 2·17 [95% CI −2·79 to 7·12; p=0·39]). Overall, 57 patients in the ATRA and idarubicin group and 40 patients in the ATRA and arsenic trioxide group reported grade 3–4 toxicities. After course 1 of treatment, grade 3–4 alopecia was reported in 23 (23%) of 98 patients in the ATRA and idarubicin group versus 5 (5%) of 95 in the ATRA and arsenic trioxide group, raised liver alanine transaminase in 11 (10%) of 108 versus 27 (25%) of 109, oral toxicity in 22 (19%) of 115 versus one (1%) of 109. After course 2 of treatment, grade 3–4 alopecia was reported in 25 (28%) of 89 patients in the ATRA and idarubicin group versus 2 (3%) of 77 in the ATRA and arsenic trioxide group; no other toxicities reached the 10% level. Patients in the ATRA and arsenic trioxide group had significantly less requirement for most aspects of supportive care than did those in the ATRA and idarubicin group. ATRA and arsenic trioxide is a feasible treatment in low-risk and high-risk patients with acute promyelocytic leukaemia, with a high cure rate and less relapse than, and survival not different to, ATRA and idarubicin, with a low incidence of liver toxicity. However, no improvement in quality of life was seen. Cancer Research UK.

A decade on from the description of JAK2 V617F, the MPNs are circumscribed by an increasingly intricate landscape. There is now evidence that they are likely the result of combined genetic dysregulation, with several mutated genes involved in the regulation of epigenetic mechanisms. Epigenetic changes are not due to a change in the DNA sequence but are reversible modifications that dictate the way in which genes may be expressed (or silenced). Among the epigenetic mechanisms, DNA methylation is probably the best described. Currently known MPN‐associated mutations now include JAK2, MPL, LNK, CBL, CALR, TET2, ASXL1, IDH1, IDH2, IKZF1 and EZH2. Enhancing our knowledge about the mutation profile of patients may allow them to be stratified into risk groups which would aid clinical decision making. Ongoing work will answer whether the use of epigenetic therapies as alterative pathway targets in combination with JAK inhibitors may be more effective than single agent treatment.

Patients with FLT3-mutated AML have a high relapse rate and suboptimal outcomes. Many have co-mutations suitable for measurable residual disease (MRD) monitoring by RT-qPCR and those destined to relapse can be identified by high or rising levels of MRD, called molecular failure. This provides a window for pre-emptive intervention, but there is little evidence to guide treatment. The use of FLT3 inhibitors (FLT3i) appears attractive but their use has not yet been evaluated. We identified 56 patients treated with FLT3i at molecular failure. The FLT3 mutation was an ITD in 52, TKD in 7 and both in 3. Over half of patients had previously received midostaurin. Molecular failure occurred at a median 9.2 months from diagnosis and was treated with gilteritinib (n = 38), quizartinib (n = 7) or sorafenib (n = 11). 60% achieved a molecular response, with 45% reaching MRD negativity. Haematological toxicity was low, and 22 patients were bridged directly to allogeneic transplant with another 6 to donor lymphocyte infusion. 2-year overall survival was 80% (95%CI 69–93) and molecular event-free survival 56% (95%CI 44–72). High-sensitivity next-generation sequencing for FLT3-ITD at molecular failure identified patients more likely to benefit. FLT3i monotherapy for molecular failure is a promising strategy which merits evaluation in prospective studies.

Background Splanchnic Vein Thrombosis (SVT) is strongly associated with underlying JAK2 V617F positive myeloproliferative neoplasms (MPN). Methods Patients attending the tertiary haematology service in Northern Ireland with SVT and underlying JAK2 V617F MPN were identified by consultant staff. A retrospective audit was undertaken to examine therapeutic interventions and relevant outcomes. Descriptive statistics were used for qualitative data whilst students t-test allowed comparison of quantitative data. Results We report on the medium to long term follow-up of fourteen patients presenting with SVT on the basis of JAK2 V617F positive MPN. Females comprised 78.5% of the patients and there was an average age of 47.3 years at time of diagnosis. There was significant morbidity evident at diagnosis with liver transplantation attempted in all patients with Budd Chiari ( n  = 3), oesophageal varices present in 57.1%, ascites present in 42.8% and splenomegaly evident in 71.4%. 42.8% of patients did not exhibit classical phenotypic blood count findings for MPN at time of diagnosis. Over a median follow-up of 88.5 months (range = 8–211 months) recurrence of SVT was only documented in the setting of interventional liver procedure. Major haemorrhagic complications were recorded in 35.7% of patients and there was an association with dual anticoagulation and antiplatelet use. Recurrent thrombosis outside of the splanchnic venous system occurred in 28.5% of patients, predominantly occurring off therapeutic anticoagulation. No deaths were recorded and one transformation to myelofibrosis was seen during follow-up. Cytoreduction therapies were routinely used but had a high discontinuation rate due to cytopenias and intolerance. Conclusion This analysis highlights the complexities of management of this group of patients over a period of long follow-up with a focus on the evidence behind therapeutic options.

Background Myelofibrosis (MF) is a clonal haematopoietic disease, with median overall survival for patients with primary MF only 6.5 years. The most frequent gene mutation found in patients is JAK2 V617F , causing constitutive activation of the kinase and activation of downstream signalling. Fedratinib is an oral selective JAK2 inhibitor. It has shown activity in MF and is well-tolerated, but combination with other therapies is likely needed to achieve clonal remission. Combining a JAK2 inhibitor with an interferon may be synergistic, as haematopoietic cells are activated from quiescence (a typical kinase resistance mechanism) rendering them more sensitive to inhibition. Ropeginterferon alfa-2b is a next generation pegylated interferon-α-2b with high tolerability and clinical activity in patients with MF, however, evidence of tolerability and activity in combination with fedratinib is lacking in this setting. The aim of the FEDORA trial is to assess tolerability, safety, and activity of fedratinib with ropeginterferon alfa-2b in patients with MF who require treatment to justify further investigation in a phase III trial. Methods FEDORA is a single arm, multicentre, open-label, Bayesian phase II trial to assess tolerability, safety, and activity of fedratinib with ropeginterferon alfa-2b aiming to recruit 30 patients. Patients with JAK2 V617F positive primary or secondary MF, who are aged ≥ 18 years, have intermediate-1 with palpable splenomegaly of > 5cm, intermediate-2, or high-risk disease according to the Dynamic International Prognostic Scoring System (DIPSS), and who require treatment are eligible. The primary outcome is tolerability, whereby the combination is deemed intolerable in a patient if drug-related toxicities in the first four months of treatment lead to: either drug being discontinued; delays in treatment exceeding 28 consecutive days; or death. FEDORA uses a within-patient dose escalation regimen to ensure each patient reaches a personalised dose combination that is acceptable. Discussion FEDORA is using a Bayesian trial design and aims to provide evidence of the tolerability, safety, and activity of combining fedratinib with ropeginterferon alfa-2b upon which the decision as to whether a phase III trial is warranted will be based. Trial registration EudraCT number: 2021–004056-42. ISRCTN: 88,102,629.

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.