ABSTRACT
The fifth edition of the WHO classification and the International Consensus Classification (ICC) both include a category "myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions" (WHO, MLN-TK; ICC, M/LN-eo-TK). This rare group comprises phenotypically and prognostically heterogeneous disorders that present a significant diagnostic challenge. The rapid and reliable identification of patients with MLN-TK may be delayed due to genetic complexity and significant phenotypic differences, which include chronic phase and primary/secondary blast phase (BP) of myeloid, or lymphoid or mixed phenotype in the bone marrow (BP-BM) and/or at extramedullary sites (extramedullary disease, EMD). As a result, the entire armamentarium of conventional molecular genetic and cytogenetic techniques complemented by modern sequencing technologies such as RNA sequencing or whole genome sequencing are often required to identify an underlying TK fusion. TK inhibitors (TKIs) with variable efficacy are available for all fusion genes, but a long-term favorable clinical course under TKI monotherapy is currently only observed in MLN-PDGFRA/PDGFRB fusion genes on imatinib. Since primary/secondary BP-BM/EMD occur more frequently in MLN-FGFR1/JAK2/FLT3/ETV6::ABL1, a sequential combination of selective TKIs with or without prior intensive chemotherapy, rarely local local radiationradiotherapy and/or subsequent allogeneic hematopoietic cell transplantation should be considered.
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PURPOSE OF REVIEW: In this review, we aim to explore the optimal approach to patients presenting with eosinophilia, considering recent advances in diagnostic and therapeutic strategies. Specifically, we focus on the integration of novel therapies into clinical practice to improve patient outcomes. RECENT FINDINGS: Advanced insights into the clinical and genetic features of eosinophilic disorders have prompted revisions in diagnostic criteria by the World Health Organization classification (WHO-HAEM5) and the International Consensus Classification (ICC). These changes reflect a growing understanding of disease pathogenesis and the development of targeted treatment options. The therapeutic landscape now encompasses a range of established and novel therapies. For reactive conditions, drugs targeting the eosinophilopoiesis, such as those aimed at interleukin-5 or its receptor, have demonstrated significant potential in decreasing blood eosinophil levels and minimizing disease flare-ups and relapse. These therapies have the potential to mitigate the side effects commonly associated with prolonged use of oral corticosteroids or immunosuppressants. Myeloid and lymphoid neoplasms with eosinophilia and tyrosine kinase (TK) gene fusions are managed by various TK inhibitors with variable efficacy. Diagnosis and treatment rely on a multidisciplinary approach. By incorporating novel treatment options into clinical practice, physicians across different disciplines involved in the management of eosinophilic disorders can offer more personalized and effective care to patients. However, challenges remain in accurately diagnosing and risk-stratifying patients, as well as in navigating the complexities of treatment selection.
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Within our nationwide registry, we identified a KIT D816V mutation (KIT D816Vpos.) in 280/299 (94%) patients with advanced systemic mastocytosis (AdvSM). Age, cytopenias and the presence of additional somatic mutations confer inferior overall survival (OS). However, little is known about the characteristics of KIT D816V-negative (D816Vneg.) AdvSM. In 19 D816Vneg. patients, a combination of clinical, morphological and genetic features revealed three subgroups: (a) KIT D816H- or Y-positive SM (KIT D816H/Ypos., n = 7), predominantly presenting as mast cell leukemia (MCL; 6/7 patients), (b) MCL with negative KIT sequencing (KITneg. MCL, n = 7) and (c) KITneg. SM with associated hematologic neoplasm (KITneg. SM-AHN, n = 5). Although >70% of patients in the two MCL cohorts (KIT D816H/Ypos. and KITneg.) were classified as low/intermediate risk according to prognostic scoring systems (PSS), treatment response was poor and median OS was shorter than in a KIT D816Vpos. MCL control cohort (n = 29; 1.7 vs. 0.9 vs. 2.6 years; p < 0.04). The KITneg. SM-AHN phenotype was dominated by the heterogeneous AHN (low mast cell burden, presence of additional mutations) with a better median OS of 4.5 years. We conclude that (i) in MCL, negativity for D816V is a relevant prognostic factor and (ii) PSS fail to correctly classify D816Vneg. patients.
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In low-risk Myelodysplastic Neoplasms (MDS), increased activity of apoptosis-promoting factors such as tumor necrosis factor (TNFα) and pro-apoptotic Fas ligand (CD95L) have been described as possible pathomechanisms leading to impaired erythropoiesis. Asunercept (APG101) is a novel therapeutic fusion protein blocking CD95, which has previously shown partial efficacy in reducing transfusion requirement in a clinical phase I trial for low-risk MDS patients (NCT01736436; 2012-11-26). In the current study we aimed to evaluate the effect of Asunercept therapy on the clonal bone marrow composition to identify potential biomarkers to predict response. Bone marrow samples of n = 12 low-risk MDS patients from the above referenced clinical trial were analyzed by serial deep whole exome sequencing in a total of n = 58 time points. We could distinguish a mean of 3.5 molecularly defined subclones per patient (range 2-6). We observed a molecular response defined as reductions of dominant clone sizes by a variant allele frequency (VAF) decrease of at least 10% (mean 20%, range: 10.5-39.2%) in dependency of Asunercept treatment in 9 of 12 (75%) patients. Most of this decline in clonal populations was observed after completion of 12 weeks treatment. Particularly early and pronounced reductions of clone sizes were found in subclones driven by mutations in genes involved in regulation of methylation (n = 1 DNMT3A, n = 1 IDH2, n = 1 TET2). Our results suggest that APG101 could be efficacious in reducing clone sizes of mutated hematopoietic cells in the bone marrow of Myelodysplastic Neoplasms, which warrants further investigation.
Subject(s)
Myelodysplastic Syndromes , Neoplasms , Humans , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/genetics , Myelodysplastic Syndromes/pathology , Clone Cells/pathology , Bone Marrow/pathology , Apoptosis , MutationABSTRACT
In 70 patients with KIT D816V positive systemic mastocytosis (SM) including 36 patients with advanced SM (AdvSM), we correlated the extent of reported mucosal mast cell ([m]MC) infiltration of the upper and/or lower gastrointestinal tract (UGIT, n = 63; LGIT, n = 64; both, n = 57) with symptoms and markers of MC burden/subtype. GI symptoms were reported by all patients (mean 2.1 number of symptoms). A strong mMC infiltration was identified in 24 patients (UGIT, 17/63, 27%; LGIT, 19/64, 30%). Concurrent involvement of UGIT and LGIT (n = 12) correlated with female gender (75%) and a higher symptom burden (mean 2.7) but not with MC burden or subtype. Significant differences between non-AdvSM and AdvSM were reported regarding food intolerance (54% vs. 17%), cramping (54% vs. 22%) and weight loss (0% vs. 64%). KIT D816V was identified in 54/56 (96%) available biopsies. In 46 patients, digital PCR revealed a correlation with low albumin levels (r = - 0.270, P = 0.069) and the KIT D816V VAF in peripheral blood (r = 0.317, P = 0.036) but not with the extent of mMC infiltration or markers of MC burden/subtype. Although MC mediator triggered GI symptoms have a substantial impact on the quality of life, correlation to objective disease parameters is lacking thus making its systematic assessment challenging.
Subject(s)
Mastocytosis, Systemic , Humans , Female , Mastocytosis, Systemic/complications , Mastocytosis, Systemic/genetics , Quality of Life , Gastrointestinal Tract , Biopsy , Food IntoleranceABSTRACT
Inhibitors of anti-apoptotic BCL-2 family proteins in combination with chemotherapy and hypomethylating agents (HMAs) are promising therapeutic approaches in acute myeloid leukemia (AML) and high-risk myelodysplastic syndromes (MDS). Alvocidib, a cyclin-dependent kinase 9 (CDK9) inhibitor and indirect transcriptional repressor of the anti-apoptotic factor MCL-1, has previously shown clinical activity in AML. Availability of biomarkers for response to the alvocidib + 5- AZA could also extend the rationale of this treatment concept to high-risk MDS. In this study, we performed a comprehensive in vitro assessment of alvocidib and 5-AZA effects in n=45 high-risk MDS patients. Our data revealed additive cytotoxic effects of the combination treatment. Mutational profiling of MDS samples identified ASXL1 mutations as predictors of response. Further, increased response rates were associated with higher gene-expression of the pro-apoptotic factor NOXA in ASXL1 mutated samples. The higher sensitivity of ASXL1 mutant cells to the combination treatment was confirmed in vivo in ASXL1Y588X transgenic mice. Overall, our study demonstrated augmented activity for the alvocidib + 5-AZA combination in higher-risk MDS and identified ASXL1 mutations as a biomarker of response for potential stratification studies.
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In a registry-based analysis of 135 patients with "myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions" (MLN-TK; FIP1L1::PDGFRA, n = 78; PDGFRB, diverse fusions, n = 26; FGFR1, diverse, n = 9; JAK2, diverse, n = 11; ETV6::ABL1, n = 11), we sought to evaluate the disease-defining characteristics. In 81/135 (60%) evaluable patients, hypereosinophilia (>1.5 × 109/l) was observed in 40/44 (91%) FIP1L1::PDGFRA and 7/7 (100%) ETV6::ABL1 positive patients but only in 13/30 (43%) patients with PDGFRB, FGFR1, and JAK2 fusion genes while 9/30 (30%) patients had no eosinophilia. Monocytosis >1 × 109/l was identified in 27/81 (33%) patients, most frequently in association with hypereosinophilia (23/27, 85%). Overall, a blast phase (BP) was diagnosed in 38/135 (28%) patients (myeloid, 61%; lymphoid, 39%), which was at extramedullary sites in 18 (47%) patients. The comparison between patients with PDGFRA/PDGFRB vs. FGFR1, JAK2, and ETV6::ABL1 fusion genes revealed a similar occurrence of primary BP (17/104, 16% vs. 8/31 26%, p = 0.32), a lower frequency (5/87, 6% vs. 8/23, 35%, p = 0.003) of and a later progression (median 87 vs. 19 months, p = 0.053) into secondary BP, and a better overall survival from diagnosis of BP (17.1 vs. 1.7 years, p < 0.0008). We conclude that hypereosinophilia with or without monocytosis and various phenotypes of BP occur at variable frequencies in MLN-TK.
Subject(s)
Eosinophilia , Lymphoma , Myeloproliferative Disorders , Humans , Receptor, Platelet-Derived Growth Factor beta/genetics , Receptor, Platelet-Derived Growth Factor alpha/genetics , Oncogene Proteins, Fusion/genetics , Myeloproliferative Disorders/complications , Eosinophilia/genetics , Eosinophilia/complications , Gene FusionABSTRACT
BACKGROUND: Robust and reliable in vitro and in vivo models of primary cells are necessary to study the pathomechanisms of Myelodysplastic Neoplasms (MDS) and identify novel therapeutic strategies. MDS-derived hematopoietic stem and progenitor cells (HSPCs) are reliant on the support of bone marrow (BM) derived mesenchymal stroma cells (MSCs). Therefore, isolation and expansion of MCSs are essential for successfully modeling this disease. For the clinical use of healthy MSCs isolated from human BM, umbilical cord blood or adipose tissue, several studies showed that xeno-free (XF) culture conditions resulted in superior growth kinetics compared to MSCs cultured in the presence of fetal bovine serum (FBS). In this present study, we investigate, whether the replacement of a commercially available MSC expansion medium containing FBS with a XF medium is beneficial for the expansion of MSCs derived from BM of MDS patients which are often difficult to cultivate. METHODS: MSCs isolated from BM of MDS patients were cultured and expanded in MSC expansion medium with FBS or XF supplement. Subsequently, the impact of culture media on growth kinetics, morphology, immunophenotype, clonogenic potential, differentiation capacity, gene expression profiles and ability to engraft in immunodeficient mouse models was evaluated. RESULTS: Significant higher cell numbers with an increase in clonogenic potential were observed during culture of MDS MSCs with XF medium compared to medium containing FBS. Differential gene expression showed an increase in transcripts associated with MSC stemness after expansion with XF. Furthermore, immunophenotypes of the MSCs and their ability to differentiate into osteoblasts, adipocytes or chondroblasts remained stable. MSCs expanded with XF media were similarly supportive for creating MDS xenografts in vivo as MSCs expanded with FBS. CONCLUSION: Our data indicate that with XF media, higher cell numbers of MDS MSCs can be obtained with overall improved characteristics in in vitro and in vivo experimental models.
Subject(s)
Bone Marrow , Mesenchymal Stem Cells , Animals , Mice , Humans , Culture Media, Serum-Free , Cell Differentiation , Mesenchymal Stem Cells/metabolism , Adipose Tissue , Cell Proliferation , Cells, CulturedABSTRACT
We sought to evaluate the efficacy of the purine analogue cladribine in 79 patients with advanced systemic mastocytosis (AdvSM) using data from the 'German Registry on Disorders of Eosinophils and Mast Cells (GREM)'. The overall response rate according to modified Valent criteria (46 evaluable patients) for first- (1L) and second-line (2L) cladribine treatment was 41% (12/29) and 35% (6/17, P = 0.690), respectively, and the median overall survival (OS, all patients evaluable) was 1.9 years (n = 48) and 1.2 years (n = 31; P = 0.311). Univariate and multivariable analyses of baseline and on-treatment parameters identified diagnosis of mast cell leukemia (hazard ratio [HR] 3.5, 95% confidence interval [CI, 1.3-9.1], P = 0.012), eosinophilia ≥ 1.5 × 109/L (HR 2.9 [CI 1.4-6.2], P = 0.006) and < 3 cycles of cladribine (HR 0.4 [CI 0.2-0.8], P = 0.008) as independent adverse prognostic parameters for OS. There was no impact of other laboratory (anemia, thrombocytopenia, serum tryptase) or genetic markers (mutations in SRSF2, ASXL1 or RUNX1) on OS. In consequence, none of the recently established prognostic scoring systems (MARS, IPSM, MAPS or GPSM) was predictive for OS. Modified Valent criteria were superior to a single factor-based response assessment (HR 2.9 [CI 1.3-6.6], P = 0.026). In conclusion, cladribine is effective in 1L and 2L treatment of AdvSM. Mast cell leukemia, eosinophilia, application of < 3 cycles and a lack of response are adverse prognostic markers.
Subject(s)
Leukemia, Mast-Cell , Mastocytosis, Systemic , Humans , Mastocytosis, Systemic/diagnosis , Mastocytosis, Systemic/drug therapy , Mastocytosis, Systemic/genetics , Cladribine/therapeutic use , Leukemia, Mast-Cell/drug therapy , Leukemia, Mast-Cell/genetics , Prognosis , RegistriesABSTRACT
Limited response rates and frequent relapses during standard of care with hypomethylating agents in myelodysplastic neoplasms (MN) require urgent improvement of this treatment indication. Here, by combining 5-azacytidine (5-AZA) with the pan-lysyl oxidase inhibitor PXS-5505, we demonstrate superior restoration of erythroid differentiation in hematopoietic stem and progenitor cells (HSPCs) of MN patients in 20/31 cases (65%) versus 9/31 cases (29%) treated with 5-AZA alone. This effect requires direct contact of HSPCs with bone marrow stroma components and is dependent on integrin signaling. We further confirm these results in vivo using a bone marrow niche-dependent MN xenograft model in female NSG mice, in which we additionally demonstrate an enforced reduction of dominant clones as well as significant attenuation of disease expansion and normalization of spleen sizes. Overall, these results lay out a strong pre-clinical rationale for efficacy of combination treatment of 5-AZA with PXS-5505 especially for anemic MN.
Subject(s)
Myelodysplastic Syndromes , Myeloproliferative Disorders , Neoplasms , Humans , Female , Mice , Animals , Azacitidine/pharmacology , Azacitidine/therapeutic use , Erythropoiesis , Protein-Lysine 6-Oxidase , Hematopoietic Stem Cells , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/pathology , Myeloproliferative Disorders/pathology , Neoplasms/pathologyABSTRACT
PURPOSE: Hydroxyurea (HY) is a reference treatment of advanced myeloproliferative neoplasms. We conducted a randomized phase III trial comparing decitabine (DAC) and HY in advanced myeloproliferative chronic myelomonocytic leukemias (CMML). PATIENTS AND METHODS: Newly diagnosed myeloproliferative CMML patients with advanced disease were randomly assigned 1:1 to intravenous DAC (20 mg/m2/d days 1-5) or HY (1-4 g/d) in 28-day cycles. The primary end point was event-free survival (EFS), events being death and acute myelomonocytic leukemia (AML) transformation or progression. RESULTS: One-hundred seventy patients received DAC (n = 84) or HY (n = 86). Median age was 72 and 74 years, and median WBC count 32.5 × 109/L and 31.2 × 109/L in the DAC and HY arms, respectively. Thirty-three percent of DAC and 31% of HY patients had CMML-2. Patients received a median of five DAC and six HY cycles. With a median follow-up of 17.5 months, median EFS was 12.1 months in the DAC arm and 10.3 months in the HY arm (hazard ratio [HR], 0.83; 95% CI, 0.59 to 1.16; P = .27). There was no significant interaction between treatment effect and blast or platelet count, anemia, CMML Prognostic Scoring System, Groupe Francophone des Myelodysplasies, or CMML Prognostic Scoring System-mol risk. Fifty-three (63%) DAC patients achieved a response compared with 30 (35%) HY patients (P = .0004). Median duration of response was similar in both arms (DAC, 16.3 months; HY, 17.4 months; P = .90). Median overall survival was 18.4 months in the DAC arm and 21.9 months in the HY arm (P = .67). Compared with HY, DAC significantly reduced the risk of CMML progression or transformation to acute myelomonocytic leukemia (cause-specific HR, 0.62; 95% CI, 0.41 to 0.94; P = .005) at the expense of death without progression or transformation (cause-specific HR, 1.55; 95% CI, 0.82 to 2.9; P = .04). CONCLUSION: Compared with HY, frontline treatment with DAC did not improve EFS in patients with advanced myeloproliferative CMML (ClinicalTrials.gov identifier: NCT02214407).
Subject(s)
Leukemia, Myelomonocytic, Acute , Leukemia, Myelomonocytic, Chronic , Humans , Aged , Leukemia, Myelomonocytic, Chronic/drug therapy , Leukemia, Myelomonocytic, Chronic/diagnosis , Decitabine , Hydroxyurea/adverse effects , Leukemia, Myelomonocytic, Acute/drug therapy , Proportional Hazards ModelsABSTRACT
Eosinophilia and eosinophil activation are recurrent features in various reactive states and certain hematologic malignancies. In patients with hypereosinophilia (HE), HE-induced organ damage is often encountered and may lead to the diagnosis of a hypereosinophilic syndrome (HES). A number of known mechanisms and etiologies contribute to the development of HE and HES. Based on these etiologies and the origin of eosinophils, HE and HES are divided into primary forms where eosinophils are clonal cells, reactive forms where an underlying reactive or neoplastic condition is detected and eosinophils are considered to be "non-clonal" cells, and idiopathic HE and HES in which neither a clonal nor a reactive underlying pathology is detected. Since 2012, this classification and the related criteria have been widely accepted and regarded as standard. However, during the past few years, new developments in the field and an increasing number of markers and targets have created a need to update these criteria and the classification of HE and HES. To address this challenge, a Working Conference on eosinophil disorders was organized in 2021. In this conference, a panel of experts representing the relevant fields, including allergy, dermatology, hematology, immunology, laboratory medicine, and pathology, met and discussed new markers and concepts as well as refinements in definitions, criteria and classifications of HE and HES. The outcomes of this conference are presented in this article and should assist in the diagnosis and management of patients with HE and HES in daily practice and in the preparation and conduct of clinical trials.
Subject(s)
Eosinophilia , Hypereosinophilic Syndrome , Hypersensitivity , Humans , Eosinophils/pathology , Eosinophilia/diagnosis , Eosinophilia/etiology , Eosinophilia/drug therapy , Syndrome , Hypersensitivity/complications , Hypereosinophilic Syndrome/etiology , Hypereosinophilic Syndrome/complicationsABSTRACT
The EUROPE phase 2 trial investigated the predictive value of biomarkers on the clinical efficacy of single agent romiplostim (ROM) treatment in patients with lower-risk myelodysplastic neoplasms (LR-MDS) and thrombocytopenia within the 'European Myelodysplastic Neoplasms Cooperative Group' (EMSCO) network. A total of 77 patients with LR-MDS and a median platelet count of 25/nl were included, all patients received ROM at a starting dose of 750 µg by SC injection weekly. Thirty-two patients (42%) achieved a hematologic improvement of platelets (HI-P) with a median duration of 340 days. Neutrophil (HI-N) and erythroid (HI-E) responses were observed in three (4%) and seven (9%) patients, respectively. We could not confirm previous reports that HI-P correlated with baseline endogenous thrombopoietin levels and platelet transfusion history, but SRSF2 mutation status and hemoglobin levels at baseline were significantly linked to HI-P. Sequential analysis of variant allelic frequency of mutations like SRSF2 did not reveal an impact of ROM on clonal evolution in both responders and non-responders. In summary, our study confirms the safety and efficacy of ROM in LR-MDS patients and may allow to better define subgroups of patients with a high likelihood of response.
Subject(s)
Myelodysplastic Syndromes , Neoplasms , Biomarkers , Hemoglobins , Humans , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/genetics , Neoplasms/drug therapy , Receptors, Fc/genetics , Receptors, Fc/therapeutic use , Recombinant Fusion Proteins/therapeutic use , Thrombopoietin/genetics , Thrombopoietin/therapeutic use , Treatment OutcomeABSTRACT
Systemic mastocytosis (SM) is characterized by multifocal accumulation of neoplastic mast cells (MCs), predominately affecting the bone marrow (BM). Imaging with computed tomography (CT) is used for assessment of bone mineral density and structure. However, the value of functional imaging with dual-energy CT (DECT) and the assessment of virtual-non-calcium attenuation values (VNCa-AV) for visualization of BM disease burden in SM has not yet been assessed. DECT of the axial skeleton was performed in 18 patients with SM (indolent SM [ISM], n = 6; smoldering SM [SSM]/advanced SM [AdvSM], n = 12) and 18 control subjects. VNCa-AV were obtained in 5 representative vertebraes per patient and correlated with laboratory, morphologic and molecular parameters. VNCa-AV strongly correlated with quantitative BM MC infiltration (r = 0.7, R2 = 0.49, P = 0.001) and serum tryptase levels (r = 0.7, R2 = 0.54, P < 0.001). Mean VNCa-AV were significantly higher in SSM/AdvSM as compared to ISM (- 9HU vs. - 54HU, P < 0.005) and controls (- 38HU, P < 0.005). Nine of 10 (90%) patients with a VNCa-AV > - 30HU and 7/7 (100%) patients with a VNCa-AV > - 10HU had SSM or AdVSM. BM VNCa-AV provide information about the MC burden of SM patients and correlate with SM subtypes. DECT may therefore serve as a supplementary tool for SM diagnosis, subclassification and monitoring in a one-stop-shop session.
Subject(s)
Bone Marrow Diseases , Mastocytosis, Systemic , Bone Marrow/diagnostic imaging , Humans , Mast Cells , Mastocytosis, Systemic/diagnostic imaging , Tomography, X-Ray Computed/methodsABSTRACT
PURPOSE: On the basis of data from the German Registry on Disorders of Eosinophils and Mast Cells, we compared the efficacy of midostaurin and cladribine in patients with advanced systemic mastocytosis (AdvSM). PATIENTS AND METHODS: Patients with AdvSM (n = 139) were treated with midostaurin only (n = 63, 45%), cladribine only (n = 23, 17%), or sequentially (midostaurin-cladribine, n = 30, 57%; cladribine-midostaurin, n = 23, 43%). Prognosis was assessed through the Mutation-Adjusted Risk Score (MARS). Besides the comparison of efficacy between midostaurin and cladribine on response (eg, organ dysfunction, bone marrow mast cell [MC] infiltration, and tryptase), overall survival (OS), and leukemia-free survival, we focused on the impact of treatment on involved non-MC lineages, for example, monocytes or eosinophils, and the KIT D816V expressed allele burden. RESULTS: Midostaurin only was superior to cladribine only with effects from responses on MC and non-MC lineages conferring on a significantly improved OS (median 4.2 v 1.9 years, P = .033) and leukemia-free survival (2.7 v 1.3 years, P = .044) on the basis of a propensity score-weighted analysis of parameters included in MARS. Midostaurin compensated the inferior efficacy of cladribine in first- and second-line treatment. On midostaurin in any line, response of eosinophilia did not improve its baseline adverse prognostic impact, whereas response of monocytosis proved to be a positive on-treatment parameter. Multivariable analysis allowed to establish three risk categories (low/intermediate/high) through the combination of MARS and the reduction of the KIT D816V expressed allele burden of ≥ 25% at month 6 (median OS not reached v 3.0 years v 1.0 year; P < .001). CONCLUSION: In this registry-based analysis, midostaurin revealed superior efficacy over cladribine in patients with AdvSM. In midostaurin-treated patients, the combination of baseline MARS and molecular response provided a compelling three-tier risk categorization (MARSv2.0) for OS.
Subject(s)
Mastocytosis, Systemic , Cladribine/therapeutic use , Humans , Mastocytosis, Systemic/drug therapy , Mastocytosis, Systemic/genetics , Proto-Oncogene Proteins c-kit/metabolism , Registries , Staurosporine/adverse effects , Staurosporine/analogs & derivativesABSTRACT
Patient-derived xenograft (PDX) models have emerged as versatile preclinical platforms for investigation of functional pathomechanisms in myelodysplastic syndromes (MDS) and other myeloid neoplasms. However, despite increasingly improved methodology, engraftment efficiencies frequently remain low. Humanized three-dimensional scaffold models (ossicle xenotransplantation models) in immunocompromised mice have recently been found to enable improved engraftment rates of healthy and malignant human hematopoiesis. We therefore interrogated the feasibility of using four different three-dimensional ossicle-based PDX models for application with primary MDS samples. In a fully standardized comparison, we evaluated scaffold materials such as Gelfoam, extracellular matrix (ECM), and human or xenogenous bone substance in comparison to intrafemoral (IF) co-injection of bone marrow (BM)-derived mesenchymal stromal cells (MSCs) and CD34+ hematopoietic stem and progenitor cells (HSPCs). Our study included13 primary MDS patient samples transplanted in parallel according to these five different conditions. Engraftment of MDS samples was assessed by flow cytometry, immunohistological staining, and molecular validation. We determined that three-dimensional ossicle-based methods achieved higher relative rates of engraftment and enabled long-term retrievability of patient-derived MSCs from implanted ossicles. In summary, HSPCs and MSCs derived from MDS BM, which did not significantly engraft in NSG mice after intrafemoral injection, were able to colonize humanized scaffold models. Therefore, these models are promising new xenotransplantation techniques for addressing preclinical and functional questions of the interaction between hematopoiesis and the BM niche in MDS.
Subject(s)
Mesenchymal Stem Cells , Myelodysplastic Syndromes , Animals , Bone Marrow Cells/pathology , Disease Models, Animal , Hematopoiesis , Hematopoietic Stem Cells/pathology , Humans , Mesenchymal Stem Cells/pathology , Mice , Myelodysplastic Syndromes/pathology , Transplantation, HeterologousABSTRACT
Preclinical research of myelodysplastic syndromes (MDSs) is hampered by a lack of feasible disease models. Previously, we have established a robust patient-derived xenograft (PDX) model for MDS. Here we demonstrate for the first time that this model is applicable as a preclinical platform to address pending clinical questions by interrogating the efficacy and safety of the thrombopoietin receptor agonist eltrombopag. Our preclinical study included n = 49 xenografts generated from n = 9 MDS patient samples. Substance efficacy was evidenced by FACS-based human platelet quantification and clonal bone marrow evolution was reconstructed by serial whole-exome sequencing of the PDX samples. In contrast to clinical trials in humans, this experimental setup allowed vehicle- and replicate-controlled analyses on a patient-individual level deciphering substance-specific effects from natural disease progression. We found that eltrombopag effectively stimulated thrombopoiesis in MDS PDX without adversely affecting the patients' clonal composition. In conclusion, our MDS PDX model is a useful tool for testing new therapeutic concepts in MDS preceding clinical trials.
Subject(s)
Benzoates/therapeutic use , Hydrazines/therapeutic use , Myelodysplastic Syndromes/drug therapy , Pyrazoles/therapeutic use , Aged , Aged, 80 and over , Animals , Apoptosis , Cell Proliferation , Female , Humans , Male , Mice , Mice, Inbred NOD , Mice, SCID , Middle Aged , Myelodysplastic Syndromes/pathology , Prognosis , Tumor Cells, Cultured , Xenograft Model Antitumor AssaysABSTRACT
BACKGROUND: Patients with systemic mastocytosis (SM) are at increased risk of hypersensitivity reactions (HRs). Although Hymenoptera venoms are the predominant triggers, cases of contrast media-induced HR (CMIHR) have also been reported and prophylactic premedication is often performed. However, data from larger series are limited and differences between indolent and advanced SM have not yet been investigated. OBJECTIVE: To determine the incidence and severity of CMIHR in all subtypes of SM. METHODS: We analyzed 162 adult patients with SM (indolent systemic mastocytosis [ISM], n = 65; advanced systemic mastocytosis [advSM], n = 97). First, the cumulative incidence of CMIHR was retrospectively assessed in the patient's history. Second, at our institution, patients underwent 332 contrast media (CM)-enhanced imaging including 80 computed tomography (CT) scans with iodine-based contrast agent and 252 magnetic resonance imaging (MRI) with a gadolinium-based contrast agent, and tolerance was assessed. RESULTS: Previous CMIHRs to CT (vomiting, n = 1, erythema, n = 1, cardiovascular shock, n = 1), and MRI (dyspnea, n = 1, cardiovascular shock, n = 1) had been reported by 4 out of 162 (2.5%) patients (ISM, n = 3; advSM, n = 1). In contrast, during or after 332 CM-enhanced CT or MRI examinations at our institution, no CMIHRs were reported. Premedication was solely given to 3 patients before CT scans, including 1 with previous CMIHR, who tolerated the imaging well. CONCLUSION: We conclude that: (1) there is a substantial discrepancy between the perception and prevalence of HRs to CM in SM; (2) reactions are scarce in ISM and even rarer in advSM; and (3) in SM patients without previous history of CM hypersensitivity, prophylactic premedication before CM-enhanced CT or MRI is dispensable.
Subject(s)
Arthropod Venoms , Mastocytosis, Systemic , Mastocytosis , Adult , Contrast Media/adverse effects , Humans , Magnetic Resonance Imaging , Retrospective StudiesABSTRACT
Within the bone marrow microenvironment, endothelial cells (EC) exert important functions. Arterial EC support hematopoiesis while H-type capillaries induce bone formation. Here, we show that BM sinusoidal EC (BM-SEC) actively control erythropoiesis. Mice with stabilized ß-catenin in BM-SEC (Ctnnb1OE-SEC) generated by using a BM-SEC-restricted Cre mouse line (Stab2-iCreF3) develop fatal anemia. While activation of Wnt-signaling in BM-SEC causes an increase in erythroblast subsets (PII-PIV), mature erythroid cells (PV) are reduced indicating impairment of terminal erythroid differentiation/reticulocyte maturation. Transplantation of Ctnnb1OE-SEC hematopoietic stem cells into wildtype recipients confirms lethal anemia to be caused by cell-extrinsic, endothelial-mediated effects. Ctnnb1OE-SEC BM-SEC reveal aberrant sinusoidal differentiation with altered EC gene expression and perisinusoidal ECM deposition and angiocrine dysregulation with de novo endothelial expression of FGF23 and DKK2, elevated in anemia and involved in vascular stabilization, respectively. Our study demonstrates that BM-SEC play an important role in the bone marrow microenvironment in health and disease.
Subject(s)
Anemia/genetics , Bone Marrow/metabolism , Cell Adhesion Molecules, Neuronal/genetics , Endothelium, Vascular/metabolism , Erythroblasts/metabolism , Erythropoiesis/genetics , beta Catenin/genetics , Anemia/metabolism , Anemia/mortality , Anemia/pathology , Animals , Bone Marrow/blood supply , Capillaries/cytology , Capillaries/metabolism , Cell Adhesion Molecules, Neuronal/metabolism , Cell Differentiation , Endothelial Cells/classification , Endothelial Cells/cytology , Endothelial Cells/metabolism , Endothelium, Vascular/cytology , Erythroblasts/classification , Erythroblasts/cytology , Female , Fibroblast Growth Factor-23/genetics , Fibroblast Growth Factor-23/metabolism , Gene Expression Regulation , Hematopoietic Stem Cell Transplantation , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/metabolism , Integrases/genetics , Integrases/metabolism , Intercellular Signaling Peptides and Proteins/genetics , Intercellular Signaling Peptides and Proteins/metabolism , Male , Mice , Mice, Transgenic , Osteogenesis , Reticulocytes/cytology , Reticulocytes/metabolism , Survival Analysis , Wnt Signaling Pathway , beta Catenin/metabolismABSTRACT
BACKGROUND: In the western world, 10-15% of women of child-bearing age suffer from iron-deficiency anemia. Iron overload due to chronic treatment with blood transfusions or hereditary hemochromatosis is much rarer. METHODS: This review is based on pertinent publications retrieved by a selective search on the pathophysiology, clinical features, and diagnostic evaluation of iron deficiency and iron overload. RESULTS: The main causes of iron deficiency are malnutrition and blood loss. Its differential diagnosis includes iron-refractory iron deficiency anemia (IRIDA), a rare congenital disease in which the hepcidin level is pathologically elevated, as well as the more common anemia of chronic disease (anemia of chronic inflammation), in which increased amounts of hepcidin are formed under the influence of interleukin-6 and enteric iron uptake is blocked as a result. Iron overload comes about through long-term transfusion treatment or a congenital disturbance of iron metabolism (hemochromatosis). Its diagnostic evaluation is based on clinical and laboratory findings, imaging studies, and specific mutation analyses. CONCLUSION: Our improving understanding of the molecular pathophysiology of iron metabolism aids in the evaluation of iron deficiency and iron overload and may in future enable treatment not just with iron supplementation or iron chelation, but also with targeted pharmacological modulation of the hepcidin regulatory system.