Lineage-specific hematopoietic growth factors

Impact of adjuvant radiotherapy on biological and clinical parameters in right-sided breast cancer

PURPOSE

In patients with right-sided breast cancer (BC) the liver might be partially irradiated during adjuvant radiotherapy (RT). Thus, we performed a prospective observational study to evaluate the dose delivered to the liver, and its potential biological impact.

PATIENTS AND METHODS

We enrolled 34 patients with right-sided BC treated with adjuvant RT. The RT schedules were either the Canadian (42.5Gy in 16 fx) or standard fractionated (50Gy in 25 fx) regimen respectively with 9 (26.5%) and 25 (73.5%) patients each, ± a boost of 10-16Gy. Each patient had a complete blood count and liver enzymes analysis, before starting and during the last week of treatment.

RESULTS

A significant decrease in white blood cells and thrombocytes counts was observed during RT. We observed a significant correlation between certain hepatic parameters and the volume of the irradiated liver and/or the mean liver dose. A significant correlation between the volume of the right lung and the liver mean dose was found (P=0.008). In the bivariate analysis, a significant correlation between fatigue and the white blood cell count's evolution was observed (P<0.025).

CONCLUSION

With the standard RT technique, incidental irradiation of the liver was documented in a large number of patients, and some significant hepatic parameters alterations were observed, without an apparent clinical impact, but this study cannot exclude them. The liver mean dose was correlated with the right lung volume suggesting that deep inspiration breath hold (DIBH) techniques may represent a way to decrease the liver dose. These findings need to be evaluated in further larger studies.

Targeting HDL in tumor microenvironment: New hope for cancer therapy

Epidemiological studies have shown that plasma HDL-C levels are closely related to the risk of prostate cancer, breast cancer, and other malignancies. As one of the key carriers of cholesterol regulation, high-density lipoprotein (HDL) plays an important role in tumorigenesis and cancer development through anti-inflammation, antioxidation, immune-modulation, and mediating cholesterol transportation in cancer cells and noncancer cells. In addition, the occurrence and progression of cancer are closely related to the alteration of the tumor microenvironment (TME). Cancer cells synthesize and secrete a variety of cytokines and other factors to promote the reprogramming of surrounding cells and shape the microenvironment suitable for cancer survival. By analyzing the effect of HDL on the infiltrating immune cells in the TME, as well as the relationship between HDL and tumor-associated angiogenesis, it is suggested that a moderate increase in the level of HDL in vivo with consequent improvement of the function of HDL in the TME and induction of intracellular cholesterol efflux may be a promising strategy for cancer therapy.

Systems Modeling to Quantify Safety Risks in Early Drug Development: Using Bifurcation Analysis and Agent-Based Modeling as Examples

Quantitative Systems Toxicology (QST) models, recapitulating pharmacokinetics and mechanism of action together with the organic response at multiple levels of biological organization, can provide predictions on the magnitude of injury and recovery dynamics to support study design and decision-making during drug development. Here, we highlight the application of QST models to predict toxicities of cancer treatments, such as cytopenia(s) and gastrointestinal adverse effects, where narrow therapeutic indexes need to be actively managed. The importance of bifurcation analysis is demonstrated in QST models of hematologic toxicity to understand how different regions of the parameter space generate different behaviors following cancer treatment, which results in asymptotically stable predictions, yet highly irregular for specific schedules, or oscillating predictions of blood cell levels. In addition, an agent-based model of the intestinal crypt was used to simulate how the spatial location of the injury within the crypt affects the villus disruption severity. We discuss the value of QST modeling approaches to support drug development and how they align with technological advances impacting trial design including patient selection, dose/regimen selection, and ultimately patient safety.

Immunomodulatory effects of bee pollen on doxorubicin-induced bone marrow/spleen immunosuppression in rat

This study investigated the immunomodulatory effects of Bee Pollen (BP) on Doxorubicin (DOX)-induced bone marrow/spleen suppression in rats. 48 Wistar rats were divided into 6 groups (n = 8/group); control, DOX (5 mg/kg), BP (100 mg/kg), BP (200 mg/kg), BP (100 mg/kg) +DOX, and BP (200 mg/kg) +DOX groups. BP was administered orally for 42 days and 5 mg/kg of DOX was injected intravenously at days 7, 14, 21, 28, 35 and 42. Hematological parameters, antioxidant enzymes and inflammatory cytokines were measured. Apoptosis-related genes were investigated using Real-Time PCR and western blot. DOX significantly decreased blood cells count, cytokines, and antioxidant enzyme. It also increased the expression of apoptotic genes in spleen and BM. The BP significantly improved hematopoietic function, antioxidant parameters, and serum levels of hematopoietic simulating-cytokines. Also, BP significantly reduced the expression of apoptotic genes. These results confirm the immunomodulatory activity of BP in DOX-induced biochemical, molecular and histological immunosuppression. PRACTICAL APPLICATIONS: Chemotherapy drugs are being developed every day but are limited due to their side effects. The most important side effect of chemotherapy drugs is the suppression of hematopoiesis through its direct effect on bone marrow and hematopoietic cells. Today, many studies are done on natural, synthetic and semi-synthetic compounds to reduce the effects of chemotherapy drugs. Compounds that, along with chemotherapy drugs in the treatment of various tumors, maintain the hematopoietic pathway, synergize the antitumor effects of chemotherapy drugs, and also protect other organs of the body from free radical damage produced by chemotherapy drugs. One of these natural compounds is bee pollen, which has all the properties mentioned in chemotherapy supplements and can be used in the pharmaceutical industry.

Long-term evaluation of temporomandibular disorders in association with cytokine and autoantibody status in young women

Temporomandibular disorders (TMD) is a chronic pain disease affecting 4-60% of general population. Its suggested etiology includes mechanical overloading to related structures, psychosocial factors, and genetic vulnerability. However, its pathogenesis is yet to be fully understood, especially in cases with a higher level of pain and more associated comorbidities. Recently chronic systemic inflammation and possible autoimmunity has been indicated in several pain conditions as the underlying mechanism of chronicity but this aspect has not been rigorously investigated in TMD. This article focuses on analyzing the levels of cytokines, chemokines, autoantibodies and nonspecific inflammatory markers and comparing their levels according to pain severity and duration in 66 female TMD patients in their 20 s and investigating their association with clinical indices of TMD and comorbidities. The high pain disability group showed decreased range of jaw function and more pain on palpation of capsule areas compared to the low pain disability group. Comorbidities such as anxiety and sleep disturbance were also significantly more prevalent. The level of IL-8 and IgG were significantly higher in the high pain disability group. IL-2, -8, -13, IFN- γ, RANTES, PGE2, and thrombopoietin levels showed a significant effect on indices reflecting jaw function, generalized pain intensity, and health related quality of life. Such results imply that longer pain duration and higher pain intensity is associated with higher levels of systemic inflammation suggesting the possible role of immunologic disturbance as an underlying factor of chronic TMD pain and warranting further investigation for its consideration in diagnosis and treatment.

Proteomics: A Tool to Study Platelet Function

Platelets are components of the blood that are highly reactive, and they quickly respond to multiple physiological and pathophysiological processes. In the last decade, it became clear that platelets are the key components of circulation, linking hemostasis, innate, and acquired immunity. Protein composition, localization, and activity are crucial for platelet function and regulation. The current state of mass spectrometry-based proteomics has tremendous potential to identify and quantify thousands of proteins from a minimal amount of material, unravel multiple post-translational modifications, and monitor platelet activity during drug treatments. This review focuses on the role of proteomics in understanding the molecular basics of the classical and newly emerging functions of platelets. including the recently described role of platelets in immunology and the development of COVID-19.The state-of-the-art proteomic technologies and their application in studying platelet biogenesis, signaling, and storage are described, and the potential of newly appeared trapped ion mobility spectrometry (TIMS) is highlighted. Additionally, implementing proteomic methods in platelet transfusion medicine, and as a diagnostic and prognostic tool, is discussed.

Kinetics of peripheral blood neutrophils in severe coronavirus disease 2019

OBJECTIVES

Emerging evidence of dysregulation of the myeloid cell compartment urges investigations on neutrophil characteristics in coronavirus disease 2019 (COVID-19). We isolated neutrophils from the blood of COVID-19 patients receiving general ward care and from patients hospitalised at intensive care units (ICUs) to explore the kinetics of circulating neutrophils and factors important for neutrophil migration and activation.

METHODS

Multicolour flow cytometry was exploited for the analysis of neutrophil differentiation and activation markers. Multiplex and ELISA technologies were used for the quantification of protease, protease inhibitor, chemokine and cytokine concentrations in plasma. Neutrophil polarisation responses were evaluated microscopically. Gelatinolytic and metalloproteinase activity in plasma was determined using a fluorogenic substrate. Co-culturing healthy donor neutrophils with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) allowed us to investigate viral replication in neutrophils.

RESULTS

Upon ICU admission, patients displayed high plasma concentrations of granulocyte-colony-stimulating factor (G-CSF) and the chemokine CXCL8, accompanied by emergency myelopoiesis as illustrated by high levels of circulating CD10-, immature neutrophils with reduced CXCR2 and C5aR expression. Neutrophil elastase and non-metalloproteinase-derived gelatinolytic activity were increased in plasma from ICU patients. Significantly higher levels of circulating tissue inhibitor of metalloproteinase 1 (TIMP-1) in patients at ICU admission yielded decreased total MMP proteolytic activity in blood. COVID-19 neutrophils were hyper-responsive to CXCL8 and CXCL12 in shape change assays. Finally, SARS-CoV-2 failed to replicate inside human neutrophils.

CONCLUSION

Our study provides detailed insights into the kinetics of neutrophil phenotype and function in severe COVID-19 patients, and supports the concept of an increased neutrophil activation state in the circulation.

Tissue Homeostasis and Inflammation

There is a growing interest in understanding tissue organization, homeostasis, and inflammation. However, despite an abundance of data, the organizing principles of tissue biology remain poorly defined. Here, we present a perspective on tissue organization based on the relationships between cell types and the functions that they perform. We provide a formal definition of tissue homeostasis as a collection of circuits that regulate specific variables within the tissue environment, and we describe how the functional organization of tissues allows for the maintenance of both tissue and systemic homeostasis. This leads to a natural definition of inflammation as a response to deviations from homeostasis that cannot be reversed by homeostatic mechanisms alone. We describe how inflammatory signals act on the same cellular functions involved in normal tissue organization and homeostasis in order to coordinate emergency responses to perturbations and ultimately return the system to a homeostatic state. Finally, we consider the hierarchy of homeostatic and inflammatory circuits and the implications for the development of inflammatory diseases.

Familial thrombocytopenia due to a complex structural variant resulting in a WAC-ANKRD26 fusion transcript

Advances in genome sequencing have resulted in the identification of the causes for numerous rare diseases. However, many cases remain unsolved with standard molecular analyses. We describe a family presenting with a phenotype resembling inherited thrombocytopenia 2 (THC2). THC2 is generally caused by single nucleotide variants that prevent silencing of ANKRD26 expression during hematopoietic differentiation. Short-read whole-exome and genome sequencing approaches were unable to identify a causal variant in this family. Using long-read whole-genome sequencing, a large complex structural variant involving a paired-duplication inversion was identified. Through functional studies, we show that this structural variant results in a pathogenic gain-of-function WAC-ANKRD26 fusion transcript. Our findings illustrate how complex structural variants that may be missed by conventional genome sequencing approaches can cause human disease.

A model and test for coordinated polygenic epistasis in complex traits

Interactions between genetic variants-epistasis-is pervasive in model systems and can profoundly impact evolutionary adaption, population disease dynamics, genetic mapping, and precision medicine efforts. In this work, we develop a model for structured polygenic epistasis, called coordinated epistasis (CE), and prove that several recent theories of genetic architecture fall under the formal umbrella of CE. Unlike standard epistasis models that assume epistasis and main effects are independent, CE captures systematic correlations between epistasis and main effects that result from pathway-level epistasis, on balance skewing the penetrance of genetic effects. To test for the existence of CE, we propose the even-odd (EO) test and prove it is calibrated in a range of realistic biological models. Applying the EO test in the UK Biobank, we find evidence of CE in 18 of 26 traits spanning disease, anthropometric, and blood categories. Finally, we extend the EO test to tissue-specific enrichment and identify several plausible tissue-trait pairs. Overall, CE is a dimension of genetic architecture that can capture structured, systemic forms of epistasis in complex human traits.

In-Depth Analysis of the Hidradenitis Suppurativa Serum Proteome Identifies Distinct Inflammatory Subtypes

Hidradenitis suppurativa is a chronic inflammatory dermatosis with presentations ranging from painful nodules and abscesses to draining tunnels. Using an unbiased proteomics approach, we assessed cardiovascular-, cardiometabolic-, and inflammation-related biomarkers in the serum of patients with moderate-to-severe hidradenitis suppurativa. The serum of patients with hidradenitis suppurativa clustered separately from that of healthy controls and had an upregulation of neutrophil-related markers (Cathepsin D, IL-17A, CXCL1). Patients with histologically diagnosed dermal tunnels had higher serum lipocalin-2 levels compared with those without tunnels. Consistent with this, patients with tunnels had a more neutrophilic-rich serum signature, marked by Cathepsin D, IL-17A, and IL-17D alterations. There was a significant serum‒skin correlation between proteins in the serum and the corresponding mRNA expression in skin biopsies, with healthy-appearing perilesional skin demonstrating a significant correlation with neutrophil-related proteins in the serum. CSF3 mRNA levels in lesional skin significantly correlated with neutrophil-related proteins in the serum, suggesting that CFS3 in the skin may be a driver of neutrophilic inflammation. Clinical significantly correlated with the levels of lipocalin-2 and IL-17A in the serum. Using an unbiased, large-scale proteomic approach, we demonstrate that hidradenitis suppurativa is a systemic neutrophilic dermatosis, with a specific molecular signature associated with the presence of dermal tunnels.

Baseline thrombopoietin level is associated with platelet count improvement in thrombocytopenic chronic hepatitis C patients after successful direct-acting antiviral agent therapy

BACKGROUND

Thrombocytopenia can rapidly improve in chronic hepatitis C (CHC) patients receiving direct-acting antiviral agents (DAA). The role of baseline (BL) thrombopoietin (TPO) in this phenomenon is unclear.

METHODS

From June 2016 to February 2019, a total of 104 CHC patients receiving DAA, with a sustained virologic response and BL thrombocytopenia, at Dalin Tzu Chi Hospital, were enrolled in this retrospective study. Significant platelet count improvement and platelet count improvement ratio were analyzed for correlation with BL TPO.

RESULTS

This cohort included 40 men (38.5%). Seventy-two (69.2%) patients had advanced fibrosis. The platelet count [median (range)] increased from 110.5 (32-149) × 10³/µL at BL to 116.5 (40-196) and 118.0 (35-275) × 10³/µL at end of treatment (EOT) and 12 weeks after EOT (P12), respectively, (EOT vs. BL, P < 0.001; P12 vs. BL, P < 0.001). BL TPO was positively correlated with significant platelet count improvement (P < 0.001), platelet count improvement ratio at EOT (P = 0.004), and P12 (P < 0.001). The area under the receiver operating characteristic curve and optimal cutoffs (pg/ml) were 0.77 (95% confidence interval, 0.67-0.86) and 120, respectively, for significant platelet count improvement prediction. The sensitivity, specificity, and accuracy were 88.6%, 71.7%, and 78.8%, respectively.

CONCLUSIONS

BL TPO level might be a useful marker for predicting significant platelet count improvement in thrombocytopenic patients after successful DAA therapy.

Efficacy of Low-Dose rhGM-CSF Treatment in a Patient With Severe Congenital Neutropenia Due to CSF3R Deficiency: Case Report of a Novel Biallelic CSF3R Mutation and Literature Review

This study reports the clinical manifestations, genetics, and efficacy of treatment with the efficacy of recombinant human granulocyte macrophage colony-stimulating factor (rhGM-GSF) of a 2-year-old female patient with severe congenital neutropenia (SCN) type 7 (SCN7) caused by novel biallelic mutations in the colony-stimulating factor 3 receptor (CSF3R) gene. Genetic diagnosis of the patient was performed by whole-exome and Sanger sequencing. Expression of the CSF3R gene in the peripheral neutrophils of the patient was detected by real-time PCR and Western blotting. The patient presented with recurrent suppurative tonsillitis and decreased absolute neutrophil count <0.5 × 10⁹/L. Novel heterozygous mutations were found to be inherited from each parent (maternal c.690delC [p.met231Cysfs^*32] and paternal c.64+5G>A). The patient's neutrophils had lower CSF3R mRNA and protein levels than those of the parents. Low-dose rhGM-CSF (3 μg/kg/day once a week) prevented recurrent infection in the patient. These results demonstrate that the clinical manifestations of SCN7 with biallelic CSF3R mutations and downregulated CSF3R can be effectively treated with rhGM-CSF.

Molecular and cellular mechanisms of aging in hematopoietic stem cells and their niches

Aging drives the genetic and epigenetic changes that result in a decline in hematopoietic stem cell (HSC) functioning. Such changes lead to aging-related hematopoietic/immune impairments and hematopoietic disorders. Understanding how such changes are initiated and how they progress will help in the development of medications that could improve the quality life for the elderly and to treat and possibly prevent aging-related hematopoietic diseases. Here, we review the most recent advances in research into HSC aging and discuss the role of HSC-intrinsic events, as well as those that relate to the aging bone marrow niche microenvironment in the overall processes of HSC aging. In addition, we discuss the potential mechanisms by which HSC aging is regulated.

Febrile neutropenia and role of prophylactic granulocyte colony-stimulating factor in docetaxel and cyclophosphamide chemotherapy for breast cancer

PURPOSE

Febrile neutropenia (FN) incidence during docetaxel and cyclophosphamide (TC) chemotherapy, known as a high-risk regimen, differs among countries. The role of prophylactic granulocyte colony-stimulating factor (G-CSF) in FN is unclear. This study aimed to investigate FN frequency and relative dose intensity (RDI) of TC chemotherapy in patients with breast cancer and identify the correct population requiring prophylactic G-CSF.

METHODS

In total, 205 patients with breast cancer were scheduled for TC chemotherapy (docetaxel/cyclophosphamide 75/600 mg/m², every 3 weeks, 4 cycles) as adjuvant chemotherapy. Trastuzumab (8 mg/kg; continued with 6 mg/kg) was administrated intravenously for human epidermal growth factor receptor 2 (HER2)-positive cancer. Fifty-five patients received primary prophylactic measures (G-CSF: 20 and antibiotics: 35). We investigated the frequency of FN and hospitalization, RDI, and the factors related to FN, adverse events, hospitalization, and RDI.

RESULTS

FN occurred in 70 patients (35.7%). FN incidence was noted in 41.1% without any prophylactic measures and in 5.0% with prophylactic G-CSF. In multivariate analysis, the independent risk factors of FN were older age (≥ 60 years, P = 0.017) and without primary prophylactic G-CSF (P = 0.011). Eleven patients (5.6%) were hospitalized of which 8 (72.7%) were elderly. The median RDIs of docetaxel and cyclophosphamide were 96.7% and 99.7%, respectively.

CONCLUSION

FN frequency during TC chemotherapy was high, and primary prophylactic G-CSF reduced FN incidence. Primary prophylactic G-CSF is an effective therapy for preventing FN during TC chemotherapy. However, prophylactic G-CSF should be considered for elderly patients based on the low hospitalization rate and the high RDI.

Post-Transcriptional Expression Control in Platelet Biogenesis and Function

Platelets are highly abundant cell fragments of the peripheral blood that originate from megakaryocytes. Beside their well-known role in wound healing and hemostasis, they are emerging mediators of the immune response and implicated in a variety of pathophysiological conditions including cancer. Despite their anucleate nature, they harbor a diverse set of RNAs, which are subject to an active sorting mechanism from megakaryocytes into proplatelets and affect platelet biogenesis and function. However, sorting mechanisms are poorly understood, but RNA-binding proteins (RBPs) have been suggested to play a crucial role. Moreover, RBPs may regulate RNA translation and decay following platelet activation. In concert with other regulators, including microRNAs, long non-coding and circular RNAs, RBPs control multiple steps of the platelet life cycle. In this review, we will highlight the different RNA species within platelets and their impact on megakaryopoiesis, platelet biogenesis and platelet function. Additionally, we will focus on the currently known concepts of post-transcriptional control mechanisms important for RNA fate within platelets with a special emphasis on RBPs.

Platelet-derived microparticles enhance megakaryocyte differentiation and platelet generation via miR-1915-3p

Thrombosis leads to platelet activation and subsequent degradation; therefore, replenishment of platelets from hematopoietic stem/progenitor cells (HSPCs) is needed to maintain the physiological level of circulating platelets. Platelet-derived microparticles (PMPs) are protein- and RNA-containing vesicles released from activated platelets. We hypothesized that factors carried by PMPs might influence the production of platelets from HSPCs, in a positive feedback fashion. Here we show that, during mouse acute liver injury, the density of megakaryocyte in the bone marrow increases following an increase in circulating PMPs, but without thrombopoietin (TPO) upregulation. In vitro, PMPs are internalized by HSPCs and drive them toward a megakaryocytic fate. Mechanistically, miR-1915-3p, a miRNA highly enriched in PMPs, is transported to target cells and suppresses the expression levels of Rho GTPase family member B, thereby inducing megakaryopoiesis. In addition, direct injection of PMPs into irradiated mice increases the number of megakaryocytes and platelets without affecting TPO levels. In conclusion, our data reveal that PMPs have a role in promoting megakaryocytic differentiation and platelet production.

Platelets derive from megakaryocytes, which differentiate from hematopoietic stem/progenitor cells (HSPCs). Here, Qu et al show that platelet-derived microparticles carrying miR-1915-3p target HSPCs and promote megakaryopoiesis by suppressing RHOB expression levels.

Immature cell fractions after cessation of chronic P2Y12-inhibition in patients with coronary artery diseases

Changes in circulating cell populations may promote ischemic events that occur soon after discontinuation of P2Y₁₂-inhibition. The aim of the study was to track the course of thrombopoietic and erythropoietic cells in patients with coronary artery diseases (CAD) after planned and physician-driven cessation of chronic P2Y₁₂-inhibition (clopidogrel 75 mg OD, or prasugrel 10 mg OD, or ticagrelor 90 mg BID). Cell fractions were determined in 62 patients at baseline (the last day of P2Y₁₂-inhibitor intake), on day-10, day-30, and day-180 thereafter. Immature platelet fraction (IPF), immature reticulocyte fraction (IRF), reticulocyte hemoglobin content (Ret-Hb) and red blood cell count (RBC) significantly increased from baseline to day-180 (IPF: p = .003; IRF: p = .013; Ret-Hb: p < .001; RBC: p = .044). Platelet count, leucocyte count and immature granulocyte fraction did not change over time (p = .561, p = .869, and p = .161, respectively). Fibrinogen levels significantly declined over time (p = .011), thrombopoietin levels increased in a non-significant manner (p = .379). We did not observe any significant interaction with choice of P2Y₁₂-inhibitor, therefore suggesting a drug class-effect. Our data shows, that discontinuation of dual antiplatelet therapy is associated with raised thrombopoietic and erythropoietic activity in the bone marrow, without significant upregulation of thrombopoietin. This provides further evidence for a direct stimulation of precursor cells by P2Y_12-inhibitors.

Risk of secondary hematologic malignancies associated with breast cancer chemotherapy and G-CSF support: A nationwide population-based cohort

Our study aimed to analyze the risk of hematologic malignancies (HM) associated with the use of G-CSF with chemotherapy for BC. Using the French National Health Data System, we examined the HM risks in patients diagnosed with an incident breast cancer between 2007 and 2015, who received chemotherapy for BC. Main outcomes were acute myeloid leukemia (AML), Myelodysplastic syndrome (MDS), myeloproliferative neoplasms (MPNs), multiple myeloma (MM), Hodgkin lymphoma or non-Hodgkin lymphoma (HL/NHL) and acute lymphoblastic leukemia or lymphocytic lymphoma (ALL/LL). Among a total of 122 373 BC survivors, 38.9% received chemotherapy only and 61.1% received chemotherapy + G-CSF. Overall, 781 cases of hematologic malignancies occurred. We observed a nonsignificant increase in the risk of AML (aHR, 1.3; 95% CI, 1.0-1.7), of MDS (aHR, 1.3; 95% CI, 0.9-1.8) and of ALL/LL (aHR, 2.0; 95% CI, 1.0-4.4) among patients treated by chemotherapy + G-CSF compared to chemotherapy only. In analyses by dose, we observed a slight increase in the risk of AML (1-3 doses: aHR, 1.2; 95% CI, 0.8-1.7/4+ doses: aHR, 1.3; 95% CI, 1.0-1.8) and of MDS (1-3 doses: aHR, 1.1; 95% CI, 0.7-1.7/4+ doses: aHR, 1.4; 95% CI, 1.0-1.9), a significant increase in risk of ALL (1-3 doses: aHR, 1.5; 95% CI, 0.5-3.9 / 4+ doses: aHR, 2.3; 95% CI, 1.0-5.1) with increasing cycles of G-CSF. Our population-based study showed that the ALL/LL was the only HM at increased risk with the use of growth factors with a possible dose-effect relationship. Our data regarding the risk of all the other HM are reassuring.

In The Blood: Connecting Variant to Function In Human Hematopoiesis

Genome-wide association studies (GWAS) have identified thousands of genetic variants associated with a range of human diseases and traits. However, understanding the mechanisms by which these genetic variants have an impact on associated diseases and traits, often referred to as the variant-to-function (V2F) problem, remains a significant hurdle. Solving the V2F challenge requires us to identify causative genetic variants, relevant cell types/states, target genes, and mechanisms by which variants can cause diseases or alter phenotypic traits. We discuss emerging functional approaches that are being applied to tackle the V2F problem for blood cell traits, illuminating how human genetic variation can impact on key mechanisms in hematopoiesis, as well as highlighting future prospects for this nascent field.

Awakening the HSC: Dynamic Modeling of HSC Maintenance Unravels Regulation of the TP53 Pathway and Quiescence

Hematopoietic stem cells (HSCs) provide all types of blood cells during the entire life of the organism. HSCs are mainly quiescent and can eventually enter the cell cycle to differentiate. HSCs are maintained and tightly regulated in a particular environment. The stem cell niche regulates dormancy and awakening. Deregulations of this interplay can lead to hematopoietic failure and diseases. In this paper, we present a Boolean network model that recapitulates HSC regulation in virtue of external signals coming from the niche. This Boolean network integrates and summarizes the current knowledge of HSC regulation and is based on extensive literature research. Furthermore, dynamic simulations suggest a novel systemic regulation of TP53 in homeostasis. Thereby, our model indicates that TP53 activity is balanced depending on external stimulations, engaging a regulatory mechanism involving ROS regulators and RAS activated transcription factors. Finally, we investigated different mouse models and compared them to in silico knockout simulations. Here, the model could recapitulate in vivo observed behaviors and thus sustains our results.

Characterizing Chemotherapy-Induced Neutropenia and Monocytopenia Through Mathematical Modelling

In spite of the recent focus on the development of novel targeted drugs to treat cancer, cytotoxic chemotherapy remains the standard treatment for the vast majority of patients. Unfortunately, chemotherapy is associated with high hematopoietic toxicity that may limit its efficacy. We have previously established potential strategies to mitigate chemotherapy-induced neutropenia (a lack of circulating neutrophils) using a mechanistic model of granulopoiesis to predict the interactions defining the neutrophil response to chemotherapy and to define optimal strategies for concurrent chemotherapy/prophylactic granulocyte colony-stimulating factor (G-CSF). Here, we extend our analyses to include monocyte production by constructing and parameterizing a model of monocytopoiesis. Using data for neutrophil and monocyte concentrations during chemotherapy in a large cohort of childhood acute lymphoblastic leukemia patients, we leveraged our model to determine the relationship between the monocyte and neutrophil nadirs during cyclic chemotherapy. We show that monocytopenia precedes neutropenia by 3 days, and rationalize the use of G-CSF during chemotherapy by establishing that the onset of monocytopenia can be used as a clinical marker for G-CSF dosing post-chemotherapy. This work therefore has important clinical applications as a comprehensive approach to understanding the relationship between monocyte and neutrophils after cyclic chemotherapy with or without G-CSF support.

Dental Management of Patients With Acquired and Congenital Bleeding Disorders

In an age when people are living longer and medical interventions are continually becoming more advanced, clinicians will need to be aware of systemic disorders and treatments that may cause complications in the dental setting. The Office for National Statistics' projections state that 26% of the UK population will be aged over 65 years by 2041.¹ Therefore, clinicians may often encounter patients who complain of prolonged bleeding following certain procedures, most commonly dental extractions. In the majority of cases, the cause is often a local one, which can be managed using simple local measures. However, poor management can lead to potentially fatal consequences. The aim of this paper is to update clinicians on the dental management of patients with acquired or congenital bleeding disorders, and on how to decide the most appropriate setting for safe dental care. Patient safety in the NHS is a national priority with ever greater measures being put into place to avoid patient harm. Whilst most patients can be successfully treated in primary care, for the provision of safe dental treatment, the clinician may need to make a decision regarding referral to specialist services for all dental treatment, or share care between primary care and specialist services for selected procedures.

Treatment Options for Thrombocytopenia in Patients With Chronic Liver Disease Undergoing a Scheduled Procedure

Thrombocytopenia is a consequence of portal hypertension and is the most common hematological manifestation of chronic liver disease (CLD) (ie, cirrhosis). Data indicates the rates of CLD are increasing and, as a result, so will the incidence of this complication. Although bleeding risks are only relevant when elective procedures are performed, this is a frequent concern as these procedures are commonly part of the spectrum of care for patients with cirrhosis. As such, thrombocytopenia remains a pertinent issue. Fortunately, we now have effective and accurate treatment modalities to raise platelet counts before scheduled procedures, known as thrombopoietin receptor agonists. Two drugs in this therapeutic class (avatrombopag and lusutrombopag) are now approved for the treatment of thrombocytopenia in adults with CLD undergoing a procedure and have revolutionized how this is managed. Although there is progress in the field, peer-reviewed literature and expert guidance are lacking. Recognizing these unmet needs, a group of expert hepatologists comprised this review, which summarizes the most current and relevant peer-reviewed literature on thrombocytopenia in CLD and provides clinical expertise on this timely topic.

Antisense oligonucleotide targeting of thrombopoietin represents a novel platelet depletion method to assess the immunomodulatory role of platelets

BACKGROUND

Platelets are effector cells of the innate and adaptive immune system; however, understanding their role during inflammation-driven pathologies can be challenging due to several drawbacks associated with current platelet depletion methods. The generation of antisense oligonucleotides (ASOs) directed to thrombopoietin (Tpo) mRNA represents a novel method to reduce circulating platelet count.

OBJECTIVE

To understand if Tpo-targeted ASO treatment represents a viable strategy to specifically reduce platelet count in mice.

METHODS

Female and male mice were treated with TPO-targeted ASOs and platelet count and function was assessed, in addition to circulating blood cell counts and hematopoietic stem and progenitor cells. The utility of the platelet-depletion strategy was assessed in a murine model of lower airway dysbiosis.

RESULTS AND CONCLUSIONS

Herein, we describe how in mice, ASO-mediated silencing of hepatic TPO expression reduces platelet, megakaryocyte, and megakaryocyte progenitor count, without altering platelet activity. TPO ASO-mediated platelet depletion can be achieved acutely and sustained chronically in the absence of adverse bleeding. TPO ASO-mediated platelet depletion allows for the reintroduction of new platelets, an advantage over commonly used antibody-mediated depletion strategies. Using a murine model of lung inflammation, we demonstrate that platelet depletion, induced by either TPO ASO or anti-CD42b treatment, reduces the accumulation of inflammatory immune cells, including monocytes and macrophages, in the lung. Altogether, we characterize a new platelet depletion method that can be sustained chronically and allows for the reintroduction of new platelets highlighting the utility of the TPO ASO method to understand the role of platelets during chronic immune-driven pathologies.

The Source and Dynamics of Adult Hematopoiesis: Insights from Lineage Tracing

The generation of all blood cell lineages (hematopoiesis) is sustained throughout the entire life span of adult mammals. Studies using cell transplantation identified the self-renewing, multipotent hematopoietic stem cells (HSCs) as the source of hematopoiesis in adoptive hosts and delineated a hierarchy of HSC-derived progenitors that ultimately yield mature blood cells. However, much less is known about adult hematopoiesis as it occurs in native hosts, i.e., without transplantation. Here we review recent advances in our understanding of native hematopoiesis, focusing in particular on the application of genetic lineage tracing in mice. The emerging evidence has established HSCs as the major source of native hematopoiesis, helped to define the kinetics of HSC differentiation, and begun exploring native hematopoiesis in stress conditions such as aging and inflammation. Major outstanding questions about native hematopoiesis still remain, such as its clonal composition, the nature of lineage commitment, and the dynamics of the process in humans.

Anemia of Chronic Diseases: Wider Diagnostics-Better Treatment?

Anemia of chronic diseases is a condition that accompanies a specific underlying disease, in which there is a decrease in hemoglobin, hematocrit and erythrocyte counts due to a complex process, usually initiated by cellular immunity mechanisms and pro-inflammatory cytokines and hepcidin. This is the second most common type of anemia after iron deficiency anemia in the world. Its severity generally correlates with the severity of the underlying disease. This disease most often coexists with chronic inflammation, autoimmune diseases, cancer, and kidney failure. Before starting treatment, one should undertake in-depth diagnostics, which includes not only assessment of complete blood count and biochemical parameters, but also severity of the underlying disease. The differential diagnosis of anemia of chronic diseases is primarily based on the exclusion of other types of anemia, in particular iron deficiency. The main features of anemia of chronic diseases include mild to moderate lowering of hemoglobin level, decreased percentage of reticulocyte count, low iron and transferrin concentration, but increased ferritin. Due to the increasingly better knowledge of the pathomechanism of chronic diseases and cancer biology, the diagnosis of this anemia is constantly expanding with new biochemical indicators. These include: the concentration of other hematopoietic factors (folic acid, vitamin B₁₂), hepcidin, creatinine and erythropoietin. The basic form of treatment of anemia of chronic diseases remains supplementation with iron, folic acid and vitamin B₁₂ as well as a diet rich in the above-mentioned hematopoietic factors. The route of administration (oral, intramuscular or intravenous) requires careful consideration of the benefits and possible side effects, and assessment of the patient’s clinical status. New methods of treating both the underlying disease and anemia are raising hopes. The novel methods are associated not only with supplementing deficiencies, but also with the administration of drugs molecularly targeted to specific proteins or receptors involved in the development of anemia of chronic diseases.

Management of chemotherapy-induced neutropenia in patients with cancer: 2019 guidelines of the Italian Medical Oncology Association (AIOM)

Neutropenia is the most frequent side effect of commercially available myelosuppressive drugs and its most significant complication is febrile neutropenia. It is associated with increased hospital admissions and higher probability of death. Prophylaxis with the administration of granulocyte colony-stimulating factor can prevent neutropenia caused by anticancer drugs. The correct administration of these drugs and the management of febrile neutropenia are extremely important in the treatment of patients with cancer.

Maximizing Breast Cancer Therapy with Awareness of Potential Treatment-Related Blood Disorders

In this review we summarize the impact of the various modalities of breast cancer therapy coupled with intrinsic patient factors on incidence of subsequent treatment-induced myelodysplasia and acute myelogenous leukemia (t-MDS/AML). It is clear that risk is increased for patients treated with radiation and chemotherapy at younger ages. Radiation is associated with modest risk, whereas chemotherapy, particularly the combination of an alkylating agent and an anthracycline, carries higher risk and radiation and chemotherapy combined increase the risk markedly. Recently, treatment with granulocyte colony-stimulating factor (G-CSF), but not pegylated G-CSF, has been identified as a factor associated with increased t-MDS/AML risk. Two newly identified associations may link homologous DNA repair gene deficiency and poly (ADP-ribose) polymerase inhibitor treatment to increased t-MDS/AML risk. When predisposing factors, such as young age, are combined with an increasing number of potentially leukemogenic treatments that may not confer large risk singly, the risk of t-MDS/AML appears to increase. Patient and treatment factors combine to form a biological cascade that can trigger a myelodysplastic event. Patients with breast cancer are often exposed to many of these risk factors in the course of their treatment, and triple-negative patients, who are often younger and/or BRCA positive, are often exposed to all of them. It is important going forward to identify effective therapies without these adverse associated effects and choose existing therapies that minimize the risk of t-MDS/AML without sacrificing therapeutic gain. IMPLICATIONS FOR PRACTICE: Breast cancer is far more curable than in the past but requires multimodality treatment. Great care must be taken to use the least leukemogenic treatment programs that do not sacrifice efficacy. Elimination of radiation and anthracycline/alkylating agent regimens will be helpful where possible, particularly in younger patients and possibly those with homologous repair deficiency (HRD). Use of colony-stimulating factors should be limited to those who truly require them for safe chemotherapy administration. Further study of a possible leukemogenic association with HRD and the various forms of colony-stimulating factors is badly needed.

Preoperative Nutritional Status Contributes to the Development of Neutropenia Event in Patients With Gastric Cancer Receiving CAPEOX Adjuvant Chemotherapy

Purpose: The aim of this study is to evaluate the risk factors for ≥ grade 3 neutropenia in gastric cancer patients receiving postoperative adjuvant chemotherapy. Methods: This is a retrospective study from a single tertiary referral hospital. Patients diagnosed with gastric cancer who met the inclusion criteria were included in this study. Baseline and clinicopathological characteristics of the patients were collected. Patients were followed-up for 12 months and the incidence of neutropenia were recorded. Factors associated with neutropenia of chemotherapy in cycle 1 were investigated. Results: A total of 202 patients with gastric cancer were included. All patients received oxaliplatin plus oral capecitabine (CAPEOX) as the adjuvant chemotherapy. The incidence of ≥ grade 3 neutropenia is 11.9% (24/202) in cycle 1 among all patients. In multivariate analysis, independent risk factors for ≥ grade 3 neutropenia were serum prealbumin level (p = 0.041), prognostic nutritional index (PNI) (p = 0.049) and pre-cycle neutrophil count (p = 0.007). Conclusions: Our findings for the first time showed that nutritional parameter as prealbumin level and PNI are independent risk factors for neutropenia in gastric cancer patients receiving adjuvant chemotherapy. This may provide evidence for further investigation on prophylaxis use of granulocyte colony-stimulating factor in selected high-risk patients to prevent sever neutropenia in cycle 1 of adjuvant chemotherapy.

Hematopoiesis and Cardiovascular Disease

A central feature of atherosclerosis, the most prevalent chronic vascular disease and root cause of myocardial infarction and stroke, is leukocyte accumulation in the arterial wall. These crucial immune cells are produced in specialized niches in the bone marrow, where a complex cell network orchestrates their production and release. A growing body of clinical studies has documented a correlation between leukocyte numbers and cardiovascular disease risk. Understanding how leukocytes are produced and how they contribute to atherosclerosis and its complications is, therefore, critical to understanding and treating the disease. In this review, we focus on the key cells and products that regulate hematopoiesis under homeostatic conditions, during atherosclerosis and after myocardial infarction.

Haematopoietic stem cell activity and interactions with the niche

The haematopoietic stem cell (HSC) microenvironment in the bone marrow, termed the niche, ensures haematopoietic homeostasis by controlling the proliferation, self-renewal, differentiation and migration of HSCs and progenitor cells at steady state and in response to emergencies and injury. Improved methods for HSC isolation, driven by advances in single-cell and molecular technologies, have led to a better understanding of their behaviour, heterogeneity and lineage fate and of the niche cells and signals that regulate their function. Niche regulatory signals can be in the form of cell-bound or secreted factors and other local physical cues. A combination of technological advances in bone marrow imaging and genetic manipulation of crucial regulatory factors has enabled the identification of several candidate cell types regulating the niche, including both non-haematopoietic (for example, perivascular mesenchymal stem and endothelial cells) and HSC-derived (for example, megakaryocytes, macrophages and regulatory T cells), with better topographical understanding of HSC localization in the bone marrow. Here, we review advances in our understanding of HSC regulation by niches during homeostasis, ageing and cancer, and we discuss their implications for the development of therapies to rejuvenate aged HSCs or niches or to disrupt self-reinforcing malignant niches.

Vestitol drives LPS-activated macrophages into M2 phenotype through modulation of NF-κB pathway

Previously, we demonstrated the anti-inflammatory properties of vestitol in a neutrophil model. Here, we show the effects of vestitol on macrophage activation and function. Vestitol was obtained from Brazilian red propolis after bioguided fractionation and tested at different concentrations in LPS-activated RAW 264.7 murine macrophages for nitric oxide (NO) production and cell viability. The levels of TNF-α, IL1-β, TGF-β, IL-4, IL-6, IL-10, IL-12, GM-CSF, IFN-ɣ and gene expression related to cytokines, NO, PI3K-AKT and signal transduction pathways were assayed by ELISA and RT-qPCR, respectively. Differences were determined by one-way ANOVA followed by Tukey-Kramer. Vestitol inhibited NO production by 83% at 0.55 μM without affecting cell viability when compared to the vehicle control (P < 0.05). Treatment with vestitol reduced GM-CSF, IL-6, TNF-α, IL-4 and TGF-β levels and increased IL-10 release (P < 0.05). Vestitol affected the expression of genes related to NF-κB pathway, NO synthase, and inhibition of leukocyte transmigration, namely: Ccs, Ccng1, Calm1, Tnfsf15, Il11, Gata3, Gadd45b, Cdkn1b, Csf1, Ccl5, Birc3 (negatively regulated), and Igf1 (positively regulated). Vestitol diminished the activation of NF-κB and Erk 1/2 pathways and induced macrophages into M2-like polarization. The modulatory effects of vestitol are due to inhibition of NF-κB and Erk 1/2 signaling pathways, which are associated with the production of pro-inflammatory factors.

Phospho-Profiling Linking Biology and Clinics in Pediatric Acute Myeloid Leukemia

Supplemental Digital Content is available in the text

Aberrant activation of key signaling-molecules is a hallmark of acute myeloid leukemia (AML) and may have prognostic and therapeutic implications. AML summarizes several disease entities with a variety of genetic subtypes. A comprehensive model spanning from signal activation patterns in major genetic subtypes of pediatric AML (pedAML) to outcome prediction and pre-clinical response to signaling inhibitors has not yet been provided. We established a high-throughput flow-cytometry based method to assess activation of hallmark phospho-proteins (phospho-flow) in 166 bone-marrow derived pedAML samples under basal and cytokine stimulated conditions. We correlated levels of activated phospho-proteins at diagnosis with relapse incidence in intermediate (IR) and high risk (HR) subtypes. In parallel, we screened a set of signaling inhibitors for their efficacy against primary AML blasts in a flow-cytometry based ex vivo cytotoxicity assay and validated the results in a murine xenograft model.

Certain phospho-signal patterns differ between genetic subtypes of pedAML. Some are consistently seen through all AML subtypes such as pSTAT5. In IR/HR subtypes high levels of GM-CSF stimulated pSTAT5 and low levels of unstimulated pJNK correlated with increased relapse risk overall. Combination of GM-CSF/pSTAT5^high and basal/pJNK^low separated three risk groups among IR/HR subtypes. Out of 10 tested signaling inhibitors, midostaurin most effectively affected AML blasts and simultaneously blocked phosphorylation of multiple proteins, including STAT5. In a mouse xenograft model of KMT2A-rearranged pedAML, midostaurin significantly prolonged disease latency. Our study demonstrates the applicability of phospho-flow for relapse-risk assessment in pedAML, whereas functional phenotype-driven ex vivo testing of signaling inhibitors may allow individualized therapy.

Cytokine receptor splice variants in hematologic diseases

Cytokine and cytokine receptors are important regulators of hematopoiesis. Hematopoietic stem cells (HSCs) and progenitors differentiate into the myeloid or lymphoid lineage in response to specific cytokines. Cell-type specific receptors are expressed on committed progenitors that bind to other late-acting cytokines that are involved in terminal differentiation of hematopoietic cells. In normal hematopoiesis, these receptors undergo alternative splicing and are developmentally regulated. Splicing changes can significantly affect the structure and function of the receptors resulting in alterations of either the extracellular ligand binding domain or the cytoplasmic signaling domain responsible for cellular growth and differentiation. Most alternatively spliced isoforms generally lose the ability to promote differentiation. Evidently, overexpression of naturally occurring cytokine receptor alternate isoforms are observed in multiple myeloid diseases such as myelodysplastic syndromes (MDS), acute myeloid leukemia (AML), and polycythemia vera (PV). The purpose of this review is to introduce the various isoforms of key cytokine receptors that play a crucial role in myeloid development and their potential role in myeloid diseases.

Induction of differentiation of human stem cells ex vivo: Toward large-scale platelet production

Platelet transfusion is one of the most reliable strategies to cure patients suffering from thrombocytopenia or platelet dysfunction. With the increasing demand for transfusion, however, there is an undersupply of donors to provide the platelet source. Thus, scientists have sought to design methods for deriving clinical-scale platelets ex vivo. Although there has been considerable success ex vivo in the generation of transformative platelets produced by human stem cells (SCs), the platelet yields achieved using these strategies have not been adequate for clinical application. In this review, we provide an overview of the developmental process of megakaryocytes and the production of platelets in vivo and ex vivo, recapitulate the key advances in the production of SC-derived platelets using several SC sources, and discuss some strategies that apply three-dimensional bioreactor devices and biochemical factors synergistically to improve the generation of large-scale platelets for use in future biomedical and clinical settings.

Mecapegfilgrastim in Chemotherapy-Induced Neutropenia: A Profile of Its Use in China

Mecapegfilgrastim (HHPG-19K) is a long-acting pegylated recombinant human granulocyte-colony stimulating factor (rhG-CSF) that is administered subcutaneously as prophylaxis once per chemotherapy cycle as a weight-adjusted dose of 100 µg/kg or as a 6 mg fixed dose. It is approved in China to reduce the incidence of infection, as manifested by febrile neutropenia, in patients with non-myeloid malignancies receiving myelosuppressive anti-cancer therapy associated with a clinically significant incidence of febrile neutropenia. In phase III trials, once per cycle prophylaxis with mecapegfilgrastim was more effective than placebo in reducing the incidence of grade ≥ 3 neutropenia in cycle 1 in patients with advanced non-small cell lung cancer and was more effective than filgrastim at reducing the mean duration of grade ≥ 3 neutropenia in cycle 1 in patients with breast cancer. The tolerability and safety profiles of mecapegfilgrastim were similar to those of filgrastim, with no unexpected adverse events (AEs); most adverse reactions in cycle 1 were mild or moderate in severity. Thus, mecapegfilgrastim is an effective and generally well tolerated treatment option for patients with non-myeloid malignancies receiving myelosuppressive chemotherapy, and extends the options available for managing chemotherapy-induced neutropenia in China.

New Small Molecule Drugs for Thrombocytopenia: Chemical, Pharmacological, and Therapeutic Use Considerations

This review provides details about three small molecules that were recently approved by the FDA for the treatment of thrombocytopenia. The new treatments include lusutrombopag, avatrombopag, and fostamatinib. The first two drugs are orally active thrombopoietin receptor (TPO-R) agonists which are FDA-approved for the treatment of thrombocytopenia in adult patients with chronic liver disease who are scheduled to undergo a procedure. Fostamatinib is orally active prodrug that, after activation, becomes spleen tyrosine kinase (SYK) inhibitor. Fostamatinib is currently used to treat chronic and refractory immune thrombocytopenia in patients who have had insufficient response to previous treatment. Chemical structures, available dosage forms, recommended dosing, pharmacokinetics, results of toxicity studies in animals, most frequent adverse effects, significant outcomes of the corresponding clinical trials, and their use in specific patient populations are thoroughly described. Described also is a comparative summary of the different aspects of five currently available therapies targeting TPO-R or SYK for the treatment of thrombocytopenia.

Topological control of cytokine receptor signaling induces differential effects in hematopoiesis

Although tunable signaling by G protein-coupled receptors can be exploited through medicinal chemistry, a comparable pharmacological approach has been lacking for the modulation of signaling through dimeric receptors, such as those for cytokines. We present a strategy to modulate cytokine receptor signaling output by use of a series of designed C2-symmetric cytokine mimetics, based on the designed ankyrin repeat protein (DARPin) scaffold, that can systematically control erythropoietin receptor (EpoR) dimerization orientation and distance between monomers. We sampled a range of EpoR geometries by varying intermonomer angle and distance, corroborated by several ligand-EpoR complex crystal structures. Across the range, we observed full, partial, and biased agonism as well as stage-selective effects on hematopoiesis. This surrogate ligand strategy opens access to pharmacological modulation of therapeutically important cytokine and growth factor receptor systems.

Smoking and Increased White and Red Blood Cells

Objective—

Whether tobacco smoking causally affects white and red blood cells and thrombocyte counts is unknown. Using a Mendelian randomization approach, we tested the hypothesis that smoking causes increases in these blood cell indices.

Approach and Results—

We included 104 607 white Danes aged 20 to 100 years from the Copenhagen General Population Study with information on blood cell indices, smoking habits, and CHRNA3 (alpha 3 nicotinic cholinergic receptor) rs1051730 genotype, where the T allele causes higher tobacco consumption; 41 759 were former smokers and 17 852 current smokers. In multivariable adjusted observational analyses and compared with never smokers, white blood cells were associated with up to 19% increases, thrombocytes with up to 4.7% increases, and red blood cell indices with up to 2.3% increases in former and current smokers. All associations were dose dependent, with tobacco consumption but for white blood cells and thrombocytes also dependent on smoking cessation time in former smokers; highest increases were for <1-year smoking cessation and lowest increases for >10-year smoking cessation. In age- and sex-adjusted genetic analyses, percent differences per T allele increase in current smokers were 1.15% (95% CI, 0.61%–1.68%) for leukocytes, 1.07% (0.38%–1.76%) for neutrophils, 1.34% (0.66%–2.02%) for lymphocytes, 1.50% (0.83%–2.18%) for monocytes, −0.60% (−1.91% to 0.74%) for eosinophils, 0.17% (−0.94% to 1.29%) for basophils, 0.38% (−0.17% to 0.93%) for thrombocytes, 0.04% (−0.14% to 0.23%) for erythrocytes, 0.34% (0.17% to 0.50%) for hematocrit, 0.26% (0.09% to 0.43%) for hemoglobin, and 0.29% (0.18% to 0.41%) for mean corpuscular volume.

Conclusions—

Smoking causes increased blood leukocytes, neutrophils, lymphocytes, and monocytes, as well as increased hematocrit, hemoglobin, and mean corpuscular volume. The observational smoking relationships were long term for white blood cells and short term for red blood cell indices.

CD110 promotes pancreatic cancer progression and its expression is correlated with poor prognosis

PURPOSE

This study aimed at investigating the function and significance of CD110 expression in pancreatic cancer.

METHODS

We performed immunohistochemical staining for CD110 expression in tumor samples from 86 patients with pancreatic cancer. We evaluated clinical outcomes and other clinicopathological factors to determine the significance of CD110 on survival and liver metastasis. We examine thrombopoietin-CD110 signaling in cancer cell extravasation in vitro and in vivo. We investigated the effects of CD110 knockdown on liver metastasis in a splenic xenograft mouse model.

RESULTS

CD110 expression in cancer cells was associated with low-histological-grade invasive ductal carcinoma, and patients with high CD110 expression had poorer prognosis (P = 0.0003). High CD110 expression was an independent predictor of liver metastasis (P = 0.0422). Knockdown of CD110 expression significantly attenuated cell migration and invasion. Treatment with thrombopoietin promoted pancreatic cancer cell extravasation. In the presence of thrombopoietin, CD110 increased cell viability through the activation of the ERK-MYC signaling pathway. Knockdown of CD110 expression inhibited liver metastases in the mouse model.

CONCLUSIONS

CD110 promotes pancreatic cancer progression and it may serve as a predictive factor for liver metastasis.

Myelodysplastic syndrome and acute myeloid leukemia after receipt of granulocyte colony-stimulating factors in older patients with non-Hodgkin lymphoma

BACKGROUND

Granulocyte colony-stimulating factors (G-CSFs), which are used for the prevention of complications from chemotherapy-related neutropenia, are linked to the risk of developing second primary myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). The objective of this study was to examine the correlation between using a specific G-CSF agent and the risk of MDS/AML among older patients with non-Hodgkin lymphoma (NHL).

METHODS

This was a retrospective cohort study of adults aged >65 years who were diagnosed with first primary NHL between 2001 and 2011. With data from the Surveillance, Epidemiology, and End Results-Medicare-linked database, adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated for the risk of MDS/AML associated with the receipt of G-CSF(filgrastim and pegfilgrastim) in Cox proportional-hazards models, which were stratified according to treatment accounting for confounding by indication.

RESULTS

Among 18,245 patients with NHL patients who had a median follow-up of 3.5 years, 56% received chemotherapy and/or immunotherapy, and G-CSF was most commonly used in those who received rituximab plus multiple chemotherapy regimens (77%). Subsequent MDS/AML diagnoses were identified in 666 patients (3.7%). A modest increased risk of MDS/AML was observed with the receipt of G-CSF (HR, 1.28; 95% CI, 1.01-1.62) and a trend was observed with increasing doses (Ptrend < .01). When specific agents were analyzed, an increased risk of MDS/AML was consistently observed with filgrastim (≥10 doses: HR, 1.67; 95% CI, 1.25-2.23), but not with pegfilgrastim (≥10 + doses: HR, 1.11; 95% CI, 0.84-1.45).

CONCLUSIONS

A higher of MDS/AML was observed in patients with NHL risk among those who received G-CSF that was specific to the use of filgrastim (≥10 doses), but not pegfilgrastim. Neutropenia prophylaxis is an essential component of highly effective NHL treatment regimens. The differential risk related to the types of G-CSF agents used warrants further study given their increasing use and newly available, US Food and Drug Administration-approved, biosimilar products.

Mutation, drift and selection in single-driver hematologic malignancy: Example of secondary myelodysplastic syndrome following treatment of inherited neutropenia

Cancer development is driven by series of events involving mutations, which may become fixed in a tumor via genetic drift and selection. This process usually includes a limited number of driver (advantageous) mutations and a greater number of passenger (neutral or mildly deleterious) mutations. We focus on a real-world leukemia model evolving on the background of a germline mutation. Severe congenital neutropenia (SCN) evolves to secondary myelodysplastic syndrome (sMDS) and/or secondary acute myeloid leukemia (sAML) in 30–40%. The majority of SCN cases are due to a germline ELANE mutation. Acquired mutations in CSF3R occur in >70% sMDS/sAML associated with SCN. Hypotheses underlying our model are: an ELANE mutation causes SCN; CSF3R mutations occur spontaneously at a low rate; in fetal life, hematopoietic stem and progenitor cells expands quickly, resulting in a high probability of several tens to several hundreds of cells with CSF3R truncation mutations; therapeutic granulocyte colony-stimulating factor (G-CSF) administration early in life exerts a strong selective pressure, providing mutants with a growth advantage. Applying population genetics theory, we propose a novel two-phase model of disease development from SCN to sMDS. In Phase 1, hematopoietic tissues expand and produce tens to hundreds of stem cells with the CSF3R truncation mutation. Phase 2 occurs postnatally through adult stages with bone marrow production of granulocyte precursors and positive selection of mutants due to chronic G-CSF therapy to reverse the severe neutropenia. We predict the existence of the pool of cells with the mutated truncated receptor before G-CSF treatment begins. The model does not require increase in mutation rate under G-CSF treatment and agrees with age distribution of sMDS onset and clinical sequencing data.

Cancer develops by multistep acquisition of mutations in a progenitor cell and its daughter cells. Severe congenital neutropenia (SCN) manifests itself through an inability to produce enough granulocytes to prevent infections. SCN commonly results from a germline ELANE mutation. Large doses of the blood growth factor granulocyte colony-stimulating factor (G-CSF) rescue granulocyte production. However, SCN frequently transforms to a myeloid malignancy, commonly associated with a somatic mutation in CSF3R, the gene encoding the G-CSF Receptor. We built a mathematical model of evolution for CSF3R mutation starting with bone marrow expansion at the fetal development stage and continuing with postnatal competition between normal and malignant bone marrow cells. We employ tools of probability theory such as multitype branching processes and Moran models modified to account for expansion of hematopoiesis during human development. With realistic coefficients, we obtain agreement with the age range at which malignancy arises in patients. In addition, our model predicts the existence of a pool of cells with mutated CSF3R before G-CSF treatment begins. Our findings may be clinically applied to intervene more effectively and selectively in SCN patients.

Cytokines and Growth Factors

Several cytokines have been used to treat autoimmune diseases, viral infections, and cancer and to regenerate the skin. In particular, interferons (INFs) have been used to treat cancer, hepatitis B and C, and multiple sclerosis, while interleukins (ILs) and tumor necrosis factors (TNFs) have been used in the management of different types of cancer. Concerning the hematopoietic growth factors (HGFs), epoetin has been used for anemia, whereas the colony-stimulating factors (CSFs) have been used for neutropenia. Other growth factors have been extensively explored, although most still need to demonstrate in vivo clinical relevance before reaching the market.This chapter provides an overview on the therapeutic applications of biological medicines containing recombinant cytokines and growth factors (HGFs and others). From this review, we concluded that the clinical relevance of recombinant cytokines has been increasing. Since the 1980s, the European Medicines Agency (EMA) and/or Food and Drug Administration (FDA) have approved 89 biological medicines containing recombinant cytokines. Among these, 18 were withdrawn, 24 are biosimilars, and 18 are orphans.So far, considerable progress has been made in discovering new cytokines, additional cytokine functions, and how they interfere with human diseases. Future prospects include the approval of more biological and biosimilar medicines for different therapeutic applications.

Hematopoietic Cytokine Gene Duplication in Zebrafish Erythroid and Myeloid Lineages

Hematopoiesis is a precisely orchestrated process regulated by the activity of hematopoietic cytokines and their respective receptors. Due to an extra round of whole genome duplication during vertebrate evolution in teleost fish, zebrafish have two paralogs of many important genes, including genes involved in hematopoiesis. Importantly, these duplication events brought increased level of complexity in such cases, where both ligands and receptors have been duplicated in parallel. Therefore, precise understanding of binding specificities between duplicated ligand-receptor signalosomes as well as understanding of their differential expression provide an important basis for future studies to better understand the role of duplication of these genes. However, although many recent studies in the field have partly addressed functional redundancy or sub-specialization of some of those duplicated paralogs, this information remains to be scattered over many publications and unpublished data. Therefore, the focus of this review is to provide an overview of recent findings in the zebrafish hematopoietic field regarding activity, role and specificity of some of the hematopoietic cytokines with emphasis on crucial regulators of the erythro-myeloid lineages.