Single-cell multi-omics identifies chronic inflammation as a driver of TP53-mutant leukemic evolution.

Understanding the genetic and nongenetic determinants of tumor protein 53 (TP53)-mutation-driven clonal evolution and subsequent transformation is a crucial step toward the design of rational therapeutic strategies. Here we carry out allelic resolution single-cell multi-omic analysis of hematopoietic stem/progenitor cells (HSPCs) from patients with a myeloproliferative neoplasm who transform to TP53-mutant secondary acute myeloid leukemia (sAML). All patients showed dominant TP53 'multihit' HSPC clones at transformation, with a leukemia stem cell transcriptional signature strongly predictive of adverse outcomes in independent cohorts, across both TP53-mutant and wild-type (WT) AML. Through analysis of serial samples, antecedent TP53-heterozygous clones and in vivo perturbations, we demonstrate a hitherto unrecognized effect of chronic inflammation, which suppressed TP53 WT HSPCs while enhancing the fitness advantage of TP53-mutant cells and promoted genetic evolution. Our findings will facilitate the development of risk-stratification, early detection and treatment strategies for TP53-mutant leukemia, and are of broad relevance to other cancer types.

A rare presentation of rapidly progressing myopathy in an adolescent.

We present a case of severe juvenile dermatomyositis with limited response to steroids in an adolescent who developed symptoms within hours after receiving Pfizer BNT162b2 coronavirus disease 2019 vaccine. The patient presented with severe weakness of proximal muscles, dyspnoea, and tachycardia. His muscle enzymes were raised, and he was diagnosed with severe juvenile dermatomyositis following magnetic resonance imaging and muscle biopsy. His management was challenging, requiring multidisciplinary input, and difficult decisions with regard to the appropriate immunomodulatory treatments. The patient had to undergo escalating immunosuppressive treatments before he began to recover clinically and biochemically. To our knowledge, this is the first case in an adolescent although a few cases of similar presentations following coronavirus disease 2019 vaccination have been reported in adults. Elucidating the potential relationship of the vaccine with this severe myopathy in an adolescent is important for global vaccination policies, but avoiding the conflation of association with causation is also crucial in the context of the pandemic.

Atypical presentation of late-onset Sandhoff disease: a case report.

BACKGROUND AND PURPOSE: Sandhoff disease is a rare type of hereditary (autosomal recessive) GM2-gangliosidosis, which is caused by mutation of the HEXB gene. Disruption of the ß subunit of the hexosaminidase (Hex) enzyme affects the function of both the Hex-A and Hex-B isoforms. The severity and the age of onset of the disease (infantile or classic; juvenile; adult) depends on the residual activity of the enzyme. The late-onset form is characterized by diverse symptomatology, comprising motor neuron disease, ataxia, tremor, dystonia, psychiatric symptoms and neuropathy. METHODS: A 36-year-old female patient has been presenting progressive, symmetrical lower limb weakness for 9 years. Detailed neurological examination revealed mild symmetrical weakness in the hip flexors without the involvement of other muscle groups. The patellar reflex was decreased on both sides. Laboratory tests showed no relevant alteration and routine electroencephalography and brain MRI were normal. Nerve conduction studies and electromyography revealed alterations corresponding to sensory neuropathy. Muscle biopsy demonstrated signs of mild neurogenic lesion. Her younger brother (32-year-old) was observed with similar symptoms. RESULTS: Detailed genetic study detected a known pathogenic missense mutation and a 15,088 base pair long known pathogenic deletion in the HEXB gene (NM_000521.4:c.1417G>A; NM_000521:c.-376-5836_669+1473del; double heterozygous state). Segregation analysis and hexosaminidase enzyme assay of the family further confirmed the diagnosis of late-onset Sandhoff disease. CONCLUSION: The purpose of this case report is to draw attention to the significance of late-onset Sandhoff disease amongst disorders presenting with proximal predominant symmetric lower limb muscle weakness in adulthood.

Low participation rates and disparities in participation in interventional clinical trials for myelodysplastic syndromes.

BACKGROUND: The development of novel therapies for the myelodysplastic syndromes (MDS) is hampered by inadequate trial recruitment. Factors contributing to low trial accrual are incompletely understood. METHODS: This study analyzed a pooled patient database from institutions of the US MDS Clinical Research Consortium to compare the characteristics of participants in interventional trials with those of patients who did not enroll in a trial. RESULTS: Data were identified for 1919 patients with MDS, and 449 of these patients (23%) participated in an interventional clinical trial. The median age of all patients was 68 years, and 64% were male. Patients who participated in trials were significantly younger than nonparticipants (P = .014), and men were more likely to participate in a trial (71% of trial participants were male, whereas 61% of nonparticipants were; P < .001). Race and ethnicity were not associated with trial enrollment. Patients in more affluent ZIP codes had a higher participation rate (P < .001). Patients with intermediate- and high-risk disease according to the revised International Prognostic Scoring System were overrepresented (P = .004), and trial participants less frequently had treatment-related disease (P < .001). In multivariable analyses, participation in a clinical trial was associated with a reduced hazard of death (P = .004). Even at large referral centers, only a minority of patients with MDS enrolled in interventional trials. CONCLUSIONS: Restrictive trial eligibility criteria that exclude patients with MDS on account of age, comorbidities, or a history of another cancer are limit enrollment of MDS patients to clinical trials. Gaining insight into the barriers to trial accrual may help investigators and study sponsors to design trials that will accrue more rapidly and augment treatment options for patients with MDS.

Single-cell sequencing in hematology.

PURPOSE OF REVIEW: In this review, we highlight key recent insights into hematopoiesis and hematological malignancies through the application of novel single-cell approaches. We particularly focus on biological insights made through the study of stem/progenitors cells in myeloid malignancy at single-cell resolution. RECENT FINDINGS: Bulk molecular profiling of hematological malignancies by next generation sequencing techniques has provided major insights into the molecular pathogenesis of blood cancers. This technology is now routinely implemented in advanced clinical diagnostics, leading to the development of novel targeted therapies. However, bulk genetic analysis can obscure key aspects of intratumoral heterogeneity which underlies critical disease events, such as treatment resistance and clonal evolution. The past few years have seen an explosion of novel techniques to analyze RNA, DNA, and protein expression at the single-cell level, providing unprecedented insight into cellular heterogeneity. SUMMARY: Given the ease of accessibility of liquid tumor biopsies, hematology is well positioned to move novel single-cell techniques towards routine application in the clinic. The present review sets out to discuss current and potential future applications for this technology in the management of patients with hematological cancers.

Impact of graft-versus-lymphoma effect on outcomes after reduced intensity conditioned-alemtuzumab allogeneic haematopoietic stem cell transplantation for patients with mature lymphoid malignancies.

Allogeneic haematopoietic stem cell transplant (allo-HSCT) offers potentially curative therapy for patients with relapsed/refractory lymphoid malignancies. Reduced-intensity conditioning (RIC) with Alemtuzumab reduces transplant-related mortality and graft-versus-host disease (GvHD), but may be associated with increased risk of relapse. With the aim of studying the effect of GVHD and donor lymphocyte infusions (DLI) on relapse, we performed a retrospective study of 288 patients (57% non-Hodgkin lymphoma, 24% Hodgkin lymphoma and 19% chronic lymphocytic leukaemia; 58% were relapsed/refractory) who underwent RIC-Alemtuzumab-HSCT between 2000 and 2012. Median follow-up time for survivors was 64 months. Five-year overall survival, relapse incidence, GvHD/relapse-free survival and non-relapse mortality were 47%, 33%, 37% and 28% respectively. Cumulative incidence of grade II-IV acute and extensive chronic GvHD was 22% and 21% at 100 days and 5 years respectively. On multivariate analysis, presence of GvHD (P = 0·03) and unrelated donor type (P = 0·03) were protective of relapse. 62/288 patients received DLI for either mixed donor chimerism (prophylactic DLI, n = 37) or clinical relapse (therapeutic DLI, n = 25). Prophylactic and therapeutic DLI successfully converted the patient to full or stable mixed donor chimerism in 78% and 56% of patients respectively. These data demonstrate good long-term outcomes and support the concept of the graft-vs-lymphoma effect as a key protective factor against relapse following RIC-Alemtuzumab allo-HSCT for patients with mature lymphoid malignancies.

Autoimmune cytopenias and thrombotic thrombocytopenic purpura.

The autoimmune cytopenias are a group of disorders resulting primarily from autoantibody-mediated destruction of blood cells, with variable clinical sequelae depending on the severity and lineage affected. Disease presentation ranges from an asymptomatic finding on a routine full blood count to an acutely unwell patient suffering the clinical consequences of severe anaemia, neutropenia or thrombocytopenia. The cytopenia may be primary or secondary to underlying infectious, immune or malignant processes. Thrombotic thrombocytopenic purpura (TTP) is a distinct, rare but potentially life-threatening entity that classically but not invariably presents with a pentad of acute onset haemolytic anaemia, thrombocytopenia, neurological symptoms, renal impairment and fevers. Autoimmune cytopenias have formed a recognised diagnostic entity for over 150 years yet continue to present a challenge in medical practice due to heterogeneity in clinical presentation and triggering factors, an incomplete understanding of underlying pathophysiology and a lack of evidence-based therapeutic approaches.

Autologous Haematopoietic Stem Cell Transplantation for Crohn's Disease: A Retrospective Survey of Long-term Outcomes From the European Society for Blood and Marrow Transplantation.

BACKGROUND AND AIMS: Autologous haematopoietic stem cell transplantation [AHSCT] is a therapeutic option for patients with severe, treatment-refractory Crohn's disease [CD]. The evidence base for AHSCT for CD is limited, with one randomised trial [ASTIC] suggesting benefit. The aim of this study was to evaluate safety and efficacy for patients undergoing AHSCT for CD in Europe, outside the ASTIC trial. METHODS: We identified 99 patients in the European Society for Blood and Marrow Transplantation [EBMT] registry, who were eligible for inclusion. Transplant and clinical outcomes were obtained for 82 patients from 19 centres in seven countries. RESULTS: Median patient age was 30 years [range 20-65]. Patients had failed or been intolerant to a median of six lines of drug therapy; 61/82 [74%] had had surgery. Following AHSCT, 53/78 [68%] experienced complete remission or significant improvement in symptoms at a median follow-up of 41 months [range 6-174]; 22/82 [27%] required no medical therapy at any point post-AHSCT. In patients who had re-started medical therapy at latest follow-up, 57% [24/42] achieved remission or significant symptomatic improvement with therapies to which they had previously lost response or been non-responsive. Treatment-free survival at 1 year was 54%. On multivariate analysis, perianal disease was associated with adverse treatment-free survival (hazard ratio 2.34, 95% confidence interval [CI] 1.14-4.83, p = 0.02). One patient died due to infectious complications [cytomegalovirus disease] at Day +56. CONCLUSIONS: In this multicentre retrospective analysis of European centres, AHSCT was relatively safe and appeared to be effective in controlling otherwise treatment-resistant Crohn's disease. Further prospective randomised controlled trials against standard of care are warranted.

Desmopressin use for minimising perioperative blood transfusion.

BACKGROUND: Blood transfusion is administered during many types of surgery, but its efficacy and safety are increasingly questioned. Evaluation of the efficacy of agents, such as desmopressin (DDAVP; 1-deamino-8-D-arginine-vasopressin), that may reduce perioperative blood loss is needed. OBJECTIVES: To examine the evidence for the efficacy of DDAVP in reducing perioperative blood loss and the need for red cell transfusion in people who do not have inherited bleeding disorders. SEARCH METHODS: We searched for randomised controlled trials (RCTs) in the Cochrane Central Register of Controlled Trials (2017, issue 3) in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (from 1937), the Transfusion Evidence Library (from 1980), and ongoing trial databases (all searches to 3 April 2017). SELECTION CRITERIA: We included randomised controlled trials comparing DDAVP to placebo or an active comparator (e.g. tranexamic acid, aprotinin) before, during, or immediately after surgery or after invasive procedures in adults or children. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. MAIN RESULTS: We identified 65 completed trials (3874 participants) and four ongoing trials. Of the 65 completed trials, 39 focused on adult cardiac surgery, three on paediatric cardiac surgery, 12 on orthopaedic surgery, two on plastic surgery, and two on vascular surgery; seven studies were conducted in surgery for other conditions. These trials were conducted between 1986 and 2016, and 11 were funded by pharmaceutical companies or by a party with a commercial interest in the outcome of the trial.The GRADE quality of evidence was very low to moderate across all outcomes. No trial reported quality of life. DDAVP versus placebo or no treatmentTrial results showed considerable heterogeneity between surgical settings for total volume of red cells transfused (low-quality evidence) and for total blood loss (very low-quality evidence) due to large differences in baseline blood loss. Consequently, these outcomes were not pooled and were reported in subgroups.Compared with placebo, DDAVP may slightly decrease the total volume of red cells transfused in adult cardiac surgery (mean difference (MD) -0.52 units, 95% confidence interval (CI) -0.96 to -0.08 units; 14 trials, 957 participants), but may lead to little or no difference in orthopaedic surgery (MD -0.02, 95% CI -0.67 to 0.64 units; 6 trials, 303 participants), vascular surgery (MD 0.06, 95% CI -0.60 to 0.73 units; 2 trials, 135 participants), or hepatic surgery (MD -0.47, 95% CI -1.27 to 0.33 units; 1 trial, 59 participants).DDAVP probably leads to little or no difference in the total number of participants transfused with blood (risk ratio (RR) 0.96, 95% CI 0.86 to 1.06; 25 trials; 1806 participants) (moderate-quality evidence).Whether DDAVP decreases total blood loss in adult cardiac surgery (MD -135.24 mL, 95% CI -210.80 mL to -59.68 mL; 22 trials, 1358 participants), orthopaedic surgery (MD -285.76 mL, 95% CI -514.99 mL to -56.53 mL; 5 trials, 241 participants), or vascular surgery (MD -582.00 mL, 95% CI -1264.07 mL to 100.07 mL; 1 trial, 44 participants) is uncertain because the quality of evidence is very low.DDAVP probably leads to little or no difference in all-cause mortality (Peto odds ratio (pOR) 1.09, 95% CI 0.51 to 2.34; 22 trials, 1631 participants) or in thrombotic events (pOR 1.36, 95% CI, 0.85 to 2.16; 29 trials, 1984 participants) (both low-quality evidence). DDAVP versus placebo or no treatment for people with platelet dysfunctionCompared with placebo, DDAVP may lead to a reduction in the total volume of red cells transfused (MD -0.65 units, 95% CI -1.16 to -0.13 units; 6 trials, 388 participants) (low-quality evidence) and in total blood loss (MD -253.93 mL, 95% CI -408.01 mL to -99.85 mL; 7 trials, 422 participants) (low-quality evidence).DDAVP probably leads to little or no difference in the total number of participants receiving a red cell transfusion (RR 0.83, 95% CI 0.66 to 1.04; 5 trials, 258 participants) (moderate-quality evidence).Whether DDAVP leads to a difference in all-cause mortality (pOR 0.72, 95% CI 0.12 to 4.22; 7 trials; 422 participants) or in thrombotic events (pOR 1.58, 95% CI 0.60 to 4.17; 7 trials, 422 participants) is uncertain because the quality of evidence is very low. DDAVP versus tranexamic acidCompared with tranexamic acid, DDAVP may increase the volume of blood transfused (MD 0.6 units, 95% CI 0.09 to 1.11 units; 1 trial, 40 participants) and total blood loss (MD 142.81 mL, 95% CI 79.78 mL to 205.84 mL; 2 trials, 115 participants) (both low-quality evidence).Whether DDAVP increases or decreases the total number of participants transfused with blood is uncertain because the quality of evidence is very low (RR 2.42, 95% CI 1.04 to 5.64; 3 trials, 135 participants).No trial reported all-cause mortality.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 2.92, 95% CI 0.32 to 26.83; 2 trials, 115 participants). DDAVP versus aprotininCompared with aprotinin, DDAVP probably increases the total number of participants transfused with blood (RR 2.41, 95% CI 1.45 to 4.02; 1 trial, 99 participants) (moderate-quality evidence).No trials reported volume of blood transfused or total blood loss and the single trial that included mortality as an outcome reported no deaths.Whether DDAVP leads to a difference in thrombotic events is uncertain because the quality of evidence is very low (pOR 0.98, 95% CI 0.06 to 15.89; 2 trials, 152 participants). AUTHORS' CONCLUSIONS: Most of the evidence derived by comparing DDAVP versus placebo was obtained in cardiac surgery, where DDAVP was administered after cardiopulmonary bypass. In adults undergoing cardiac surgery, the reduction in volume of red cells transfused and total blood loss was small and was unlikely to be clinically important. It is less clear whether DDAVP may be of benefit for children and for those undergoing non-cardiac surgery. A key area for researchers is examining the effects of DDAVP for people with platelet dysfunction. Few trials have compared DDAVP versus tranexamic acid or aprotinin; consequently, we are uncertain of the relative efficacy of these interventions.

Targeting Splicing in the Treatment of Myelodysplastic Syndromes and Other Myeloid Neoplasms.

Genome sequencing of primary cells from patients with myelodysplastic syndromes (MDS) led to the identification of recurrent heterozygous mutations in gene encoding components of the spliceosome, the cellular machinery which processes pre-messenger RNA (mRNA) to mature mRNA during gene transcription. Splicing mutations are mutually exclusive with one another and collectively represent the most common mutation class in MDS, occurring in approximately 60 % of patients overall and more than 80 % of those with ring sideroblasts. Evidence from animal models suggests that homozygous splicing mutations are lethal, and that in heterozygously mutated models, any further disruption of splicing triggers apoptosis and cell death. MDS cells with spliceosome mutations are thus uniquely vulnerable to therapies targeting splicing, which may be tolerated by healthy cells. The spliceosome is emerging as a novel therapeutic target in MDS and related myeloid neoplasms, with the first clinical trial of a splicing modulator opening in 2016.

Allogeneic stem cell transplantation in myelodysplastic syndromes: does pretransplant clonal burden matter?

PURPOSE OF REVIEW: Currently, the only potential curative therapy for myelodysplastic syndromes (MDS) is allogeneic hematopoietic stem cell transplantation (alloSCT). As alloSCT confers both a short-term mortality risk compared with conservative management, and a longer-term risk of chronic health burden from graft-versus-host disease and other complications, careful patient selection for alloSCT is essential. Here, we review data on disease burden and transplant outcomes in MDS, describing which patients stand to benefit most (and least) from alloSCT. Evidence for timing of alloSCT and modifying tumor burden prior to transplant is also discussed. RECENT FINDINGS: Although patients who undergo alloSCT with excess blasts have poorer outcomes than those transplanted with fewer blasts, the effect of clone size in patients with MDS without increased blast proportion is poorly studied, and it is also not yet known whether posttransplant outcomes can be modified with pretransplant therapy such as intensive induction chemotherapy or hypomethylating agent treatment. Randomized data are lacking. Most hematopoietic cells in patients with MDS are clonal, even in cases without increased marrow blast proportion. Certain high-risk point mutations such as TP53 seem to be associated with a worse outcome even when subclonal. SUMMARY: Patients with more than 10% blasts should be considered for cytoreductive therapy before transplant, especially if reduced intensity conditioning (alloSCT) is planned. Patients with less than 10% blasts who are appropriate candidates for transplant can proceed straight to transplant, though it appears better to delay transplant for those with lower-risk disease. Hypomethylating agent therapy may be useful as a bridge to transplant. Randomized data are eagerly awaited.

Thrombopoiesis-stimulating agents and myelodysplastic syndromes.

Thrombocytopenia in patients with myelodysplastic syndromes (MDS) is a frequent cause of haemorrhage-related morbidity and mortality, and is associated with increased risk of leukaemic transformation and reduced overall survival. In addition, thrombocytopenia in MDS limits the tolerability and therapeutic efficacy of disease-modifying therapies, such as azacitidine or lenalidomide. The recombinant human erythropoietin (rHuEPO) erythropoiesis-stimulating agents, epoetin and darbepoetin, are an established component of anaemia management in lower-risk MDS. Their success has, in turn, driven the development of haematopoietic growth factors targeting thrombocytopenia. While recombinant thrombopoietin (THPO) proved too immunogenic for clinical use, novel thrombopoiesis-stimulating agents (TSAs) have the potential to reduce bleeding events, decrease dependency on platelet transfusions and extend exposure to disease-modifying therapies. Two TSAs, eltrombopag and romiplostim, have demonstrated benefit in chronic immune thrombocytopenia purpura (ITP) and safety and efficacy data for use of these agents in MDS is growing. However, important safety concerns remain, such as the potential for stimulation of neoplastic myeloid clones by THPO agonists. In this narrative review, we discuss the rationale and biological mechanism for TSAs in MDS, describe the agents currently available and their mechanism of action, and present current clinical data relating to TSA safety and efficacy in the context of MDS.

The human squamous oesophagus has widespread capacity for clonal expansion from cells at diverse stages of differentiation.

OBJECTIVE: Knowledge of the cellular mechanisms involved in homeostasis of human squamous oesophagus in the steady state and following chronic injury is limited. We aimed to better understand these mechanisms by using a functional 3D approach. DESIGN: Proliferation, mitosis and the expression of progenitor lineage markers were assessed in normal squamous oesophagus from 10 patients by immunofluorescence on 3D epithelial whole mounts. Cells expressing differential levels of epithelial and progenitor markers were isolated using flow cytometry sorting and characterised by qPCR and IF. Their self-renewing potential was investigated by colony forming cells assays and in vitro organotypic culture models. RESULTS: Proliferation and mitotic activity was highest in the interpapillary basal layer and decreased linearly towards the tip of the papilla (p<0.0001). The orientation of mitosis was random throughout the basal layer, and asymmetric divisions were not restricted to specific cell compartments. Cells sorted into distinct populations based on the expression of epithelial and progenitor cell markers (CD34 and EpCAM) showed no difference in self-renewal in 2D culture, either as whole populations or as single cells. In 3D organotypic cultures, all cell subtypes were able to recapitulate the architecture of the tissue of origin and the main factor determining the success of the 3D culture was the number of cells plated, rather than the cell type. CONCLUSIONS: Oesophageal epithelial cells demonstrate remarkable plasticity for self-renewal. This situation could be viewed as an ex vivo wounding response and is compatible with recent findings in murine models.

Healthcare access and health beliefs of the indigenous peoples in remote Amazonian Peru.

Little is published about the health issues of traditional communities in the remote Peruvian Amazon. This study assessed healthcare access, health perceptions, and beliefs of the indigenous population along the Ampiyacu and Yaguasyacu rivers in north-eastern Peru. One hundred and seventy-nine adult inhabitants of 10 remote settlements attending health clinics were interviewed during a medical services trip in April 2012. Demographics, health status, access to healthcare, health education, sanitation, alcohol use, and smoke exposure were recorded. Our findings indicate that poverty, household overcrowding, and poor sanitation remain commonplace in this group. Furthermore, there are poor levels of health education and on-going barriers to accessing healthcare. Healthcare access and health education remain poor in the remote Peruvian Amazon. This combined with poverty and its sequelae render this population vulnerable to disease.

Cricopharyngeal myotomy for cricopharyngeus stricture in an inclusion body myositis patient with hiatus hernia: a learning experience.

Inclusion body myositis is a chronic progressive myopathy which tends not to respond to steroids and immunosuppressive treatments. Dysphagia is more common in this group than other inflammatory myopathies like polymyositis and dermatomyositis. Otolaryngologists are involved in the management of dysphagia in inclusion body myositis. They usually use a combination of cricopharyngeal myotomy, upper oesophageal dilation or botulinum injection to help with the symptoms. Cricopharyngeus myotomy is the preferred treatment in this group and patients tend to be discharged after a short stay in the hospital. However, our experience was completely different from what we expected as a relatively straightforward procedure led to severe morbidity and prolonged hospital admission due to continuous acid reflux and aspiration. We believe that the presence of hiatus hernia led to this problem as the patient's problem resolved completely after her hernia was treated.