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1.
N Engl J Med ; 386(1): 11-23, 2022 01 06.
Article in English | MEDLINE | ID: mdl-34986284

ABSTRACT

BACKGROUND: A single-group, phase 1-2 study indicated that eltrombopag improved the efficacy of standard immunosuppressive therapy that entailed horse antithymocyte globulin (ATG) plus cyclosporine in patients with severe aplastic anemia. METHODS: In this prospective, investigator-led, open-label, multicenter, randomized, phase 3 trial, we compared the efficacy and safety of horse ATG plus cyclosporine with or without eltrombopag as front-line therapy in previously untreated patients with severe aplastic anemia. The primary end point was a hematologic complete response at 3 months. RESULTS: Patients were assigned to receive immunosuppressive therapy (Group A, 101 patients) or immunosuppressive therapy plus eltrombopag (Group B, 96 patients). The percentage of patients who had a complete response at 3 months was 10% in Group A and 22% in Group B (odds ratio, 3.2; 95% confidence interval [CI], 1.3 to 7.8; P = 0.01). At 6 months, the overall response rate (the percentage of patients who had a complete or partial response) was 41% in Group A and 68% in Group B. The median times to the first response were 8.8 months (Group A) and 3.0 months (Group B). The incidence of severe adverse events was similar in the two groups. With a median follow-up of 24 months, a karyotypic abnormality that was classified as myelodysplastic syndrome developed in 1 patient (Group A) and 2 patients (Group B); event-free survival was 34% and 46%, respectively. Somatic mutations were detected in 29% (Group A) and 31% (Group Β) of the patients at baseline; these percentages increased to 66% and 55%, respectively, at 6 months, without affecting the hematologic response and 2-year outcome. CONCLUSIONS: The addition of eltrombopag to standard immunosuppressive therapy improved the rate, rapidity, and strength of hematologic response among previously untreated patients with severe aplastic anemia, without additional toxic effects. (Funded by Novartis and others; RACE ClinicalTrials.gov number, NCT02099747; EudraCT number, 2014-000363-40.).


Subject(s)
Anemia, Aplastic/therapy , Antilymphocyte Serum/therapeutic use , Benzoates/therapeutic use , Cyclosporine/therapeutic use , Hydrazines/therapeutic use , Immunosuppression Therapy , Immunosuppressive Agents/therapeutic use , Pyrazoles/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Anemia, Aplastic/drug therapy , Anemia, Aplastic/genetics , Antilymphocyte Serum/adverse effects , Benzoates/adverse effects , Cyclosporine/adverse effects , Drug Therapy, Combination , Female , Humans , Hydrazines/adverse effects , Immunosuppressive Agents/adverse effects , Male , Middle Aged , Progression-Free Survival , Prospective Studies , Pyrazoles/adverse effects , Receptors, Thrombopoietin/agonists , Remission Induction , Young Adult
2.
Haematologica ; 104(1): 147-154, 2019 01.
Article in English | MEDLINE | ID: mdl-30115656

ABSTRACT

Lenalidomide has been proven to be effective but with a distinct and difficult to manage toxicity profile in the context of chronic lymphocytic leukemia, potentially hampering combination treatment with this drug. We conducted a phase 1-2 study to evaluate the efficacy and safety of six cycles of chlorambucil (7 mg/m2 daily), rituximab (375 mg/m2 cycle 1 and 500 mg/m2 cycles 2-6) and individually-dosed lenalidomide (escalated from 2.5 mg to 10 mg) (induction-I) in first-line treatment of patients with chronic lymphocytic leukemia unfit for treatment with fludarabine, cyclophosphamide and rituximab. This was followed by 6 months of 10 mg lenalidomide monotherapy (induction-II). Of 53 evaluable patients in phase 2 of the study, 47 (89%) completed induction-I and 36 (68%) completed induction-II. In an intention-to-treat analysis, the overall response rate was 83%. The median progression-free survival was 49 months, after a median follow-up time of 27 months. The 2- and 3-year progression-free survival rates were 58% and 54%, respectively. The corresponding rates for overall survival were 98% and 95%. No tumor lysis syndrome was observed, while tumor flair reaction occurred in five patients (9%, 1 grade 3). The most common hematologic toxicity was grade 3-4 neutropenia, which occurred in 73% of the patients. In conclusion, addition of lenalidomide to a chemotherapy backbone followed by a fixed duration of lenalidomide monotherapy resulted in high remission rates and progression-free survival rates, which seem comparable to those observed with novel drug combinations including novel CD20 monoclonal antibodies or kinase inhibitors. Although lenalidomide-specific toxicity remains a concern, an individualized dose-escalation schedule is feasible and results in an acceptable toxicity profile. EuraCT number: 2010-022294-34.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Adolescent , Adult , Chlorambucil/administration & dosage , Disease-Free Survival , Feasibility Studies , Female , Humans , Lenalidomide/administration & dosage , Leukemia, Lymphocytic, Chronic, B-Cell/metabolism , Leukemia, Lymphocytic, Chronic, B-Cell/pathology , Male , Middle Aged , Rituximab/administration & dosage , Survival Rate , Vidarabine/administration & dosage , Vidarabine/analogs & derivatives
3.
Blood ; 123(25): 3873-86; quiz 4005, 2014 Jun 19.
Article in English | MEDLINE | ID: mdl-24665134

ABSTRACT

During recent years, our understanding of the pathogenesis of inherited microcytic anemias has gained from the identification of several genes and proteins involved in systemic and cellular iron metabolism and heme syntheses. Numerous case reports illustrate that the implementation of these novel molecular discoveries in clinical practice has increased our understanding of the presentation, diagnosis, and management of these diseases. Integration of these insights into daily clinical practice will reduce delays in establishing a proper diagnosis, invasive and/or costly diagnostic tests, and unnecessary or even detrimental treatments. To assist the clinician, we developed evidence-based multidisciplinary guidelines on the management of rare microcytic anemias due to genetic disorders of iron metabolism and heme synthesis. These genetic disorders may present at all ages, and therefore these guidelines are relevant for pediatricians as well as clinicians who treat adults. This article summarizes these clinical practice guidelines and includes background on pathogenesis, conclusions, and recommendations and a diagnostic flowchart to facilitate using these guidelines in the clinical setting.


Subject(s)
Anemia, Hypochromic/diagnosis , Anemia, Hypochromic/therapy , Heme/biosynthesis , Iron/metabolism , Practice Guidelines as Topic , Anemia, Hypochromic/genetics , Anemia, Iron-Deficiency/diagnosis , Anemia, Iron-Deficiency/genetics , Anemia, Iron-Deficiency/therapy , Anemia, Sideroblastic/diagnosis , Anemia, Sideroblastic/genetics , Anemia, Sideroblastic/therapy , Evidence-Based Medicine , Genetic Predisposition to Disease/genetics , Humans , Mutation
4.
Eur J Haematol ; 97(5): 479-488, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27028304

ABSTRACT

Allogeneic stem cell transplantation (allo-SCT) has the potential to induce long-term remission in multiple myeloma (MM), but the role of allo-SCT in MM is controversial due to the high rate of treatment-related mortality (TRM). However, although proteasome inhibitors and immunomodulatory drugs have improved the outcome of patients with MM, high-risk patients still have a very poor prognosis. This indicates the need for new treatment strategies and identification of patients who might benefit from allo-SCT. We therefore analyzed the outcome of one hundred and forty-seven patients with MM who received an allo-SCT at our institution (58 in first line, 89 in relapsed/refractory setting) after a median follow-up of 88.8 months. For the first-line setting, median progression-free survival (PFS) and overall survival (OS) were remarkably good, with a CR rate of 48.3%, median PFS of 30.2 months, and 10-yr OS of 51%. We found no difference in outcome for patients with high-risk metaphase cytogenetics or FISH del(13q14), but efficacy in current standard high-risk patients could not be determined. The outcome in the relapsed/refractory setting was poor, especially in the subgroup of patients relapsing within 18 months after auto-SCT. Therefore, if applied at all in these patients, improvement of allo-SCT is needed, focusing on reduction of TRM and more effective immunotherapy.


Subject(s)
Hematopoietic Stem Cell Transplantation , Multiple Myeloma/diagnosis , Multiple Myeloma/therapy , Adult , Aged , Combined Modality Therapy , Disease Progression , Disease-Free Survival , Female , Follow-Up Studies , Graft vs Host Disease/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Male , Middle Aged , Multiple Myeloma/mortality , Prognosis , Recurrence , Retreatment , Transplantation, Homologous , Treatment Outcome
6.
Haematologica ; 100(5): 677-82, 2015 May.
Article in English | MEDLINE | ID: mdl-25661441

ABSTRACT

In a prospective multicenter phase II study, we evaluated the effect of three courses of vincristine, doxorubicin and dexamethasone followed by high-dose melphalan and autologous stem cell transplantation on an intention-to-treat basis. Sixty-nine newly diagnosed patients with amyloid light chain amyloidosis were included between November 2000 and January 2006: 37 men and 32 women with a median age of 56 years, including 46% of patients with cardiac and 22% of patients with involvement of 3 or 4 organs. Initial results presented in 2008 showed a 4-year overall survival rate of 62% among all the patients, while the 4-year survival rate after transplantation was 78%. Here we report the long-term follow-up data after a median follow up of 115 months of the patients still alive. Median survival of all patients was 96 months from registration and for the transplanted patients ten years from the date of transplantation. Twelve (12%) patients died during induction therapy with vincristine, doxorubicin and dexamethasone, including 8 patients (12%) due to treatment-related mortality. Two patients died within one month following high-dose melphalan. We conclude that vincristine, doxorubicin and dexamethasone should not be applied as induction therapy for intensification in amyloid light chain amyloidosis. However, a 2-step approach consisting of a non-intensive less toxic induction therapy followed by high-dose melphalan and autologous stem cell transplantation may result in extended survival in newly diagnosed patients with amyloid light chain amyloidosis (clinicaltrials.gov identifier: 01207094).


Subject(s)
Amyloidosis/therapy , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hematopoietic Stem Cell Transplantation , Melphalan/administration & dosage , Adult , Aged , Amyloidosis/diagnosis , Amyloidosis/etiology , Amyloidosis/mortality , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Combined Modality Therapy , Dexamethasone/administration & dosage , Doxorubicin/administration & dosage , Female , Follow-Up Studies , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Remission Induction , Transplantation, Autologous , Treatment Outcome , Vincristine/administration & dosage
7.
Virchows Arch ; 484(5): 837-845, 2024 May.
Article in English | MEDLINE | ID: mdl-38602559

ABSTRACT

The classical BCR::ABL1-negative myeloproliferative neoplasms (MPN) form a group of bone marrow (BM) diseases with the potential to progress to acute myeloid leukemia or develop marrow fibrosis and subsequent BM failure. The mechanism by which BM fibrosis develops and the factors that drive stromal activation and fibrosis are not well understood. Cellular Communication Network 2 (CCN2), also known as CTGF (Connective Tissue Growth Factor), is a profibrotic matricellular protein functioning as an important driver and biomarker of fibrosis in a wide range of diseases outside the marrow. CCN2 can promote fibrosis directly or by acting as a factor downstream of TGF-ß, the latter already known to contribute to myelofibrosis in MPN.To study the possible involvement of CCN2 in BM fibrosis in MPN, we assessed CCN2 protein expression by immunohistochemistry in 75 BM biopsies (55 × MPN and 20 × normal controls). We found variable expression of CCN2 in megakaryocytes with significant overexpression in a subgroup of 7 (13%) MPN cases; 4 of them (3 × essential thrombocytemia and 1 × prefibrotic primary myelofibrosis) showed no fibrosis (MF-0), 2 (1 × post-polycythemic myelofibrosis and 1 × primary myelofibrosis) showed moderate fibrosis (MF-2), and 1 (primary myelofibrosis) severe fibrosis (MF-3). Remarkably, CCN2 expression did not correlate with fibrosis or other disease parameters such as platelet count or thrombovascular events, neither in this subgroup nor in the whole study group. This suggests that in BM of MPN patients other, CCN2-independent pathways (such as noncanonical TGF-ß signaling) may be more important for the development of fibrosis.


Subject(s)
Connective Tissue Growth Factor , Myeloproliferative Disorders , Primary Myelofibrosis , Signal Transduction , Transforming Growth Factor beta , Humans , Connective Tissue Growth Factor/metabolism , Transforming Growth Factor beta/metabolism , Primary Myelofibrosis/pathology , Primary Myelofibrosis/metabolism , Middle Aged , Male , Female , Aged , Myeloproliferative Disorders/pathology , Myeloproliferative Disorders/metabolism , Adult , Bone Marrow/pathology , Bone Marrow/metabolism , Aged, 80 and over , Immunohistochemistry , Fibrosis/pathology
8.
J Immunol ; 184(3): 1280-91, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-20038642

ABSTRACT

Chronic infections are caused by microorganisms that display effective immune evasion mechanisms. Dendritic cell (DC)-dependent T cell-mediated adaptive immunity is one of the mechanisms that have evolved to prevent the occurrence of chronic bacterial infections. In turn, bacterial pathogens have developed strategies to evade immune recognition. In this study, we show that gram-negative and gram-positive bacteria differ in their ability to activate DCs and that gram-negative bacteria are far more effective inducers of DC maturation. Moreover, we observed that only gram-negative bacteria can induce loss of adhesive podosome structures in DCs, a response necessary for the induction of effective DC migration. We demonstrate that the ability of gram-negative bacteria to trigger podosome turnover and induce DC migration reflects their capacity to selectively activate TLR4. Examining mice defective in TLR4 signaling, we show that this DC maturation and migration are mainly Toll/IL-1 receptor domain-containing adaptor-inducing IFNbeta-dependent. Furthermore, we show that these processes depend on the production of PGs by these DCs, suggesting a direct link between TLR4-mediated signaling and arachidonic metabolism. These findings demonstrate that gram-positive and gram-negative bacteria profoundly differ in their capacity to activate DCs. We propose that this inability of gram-positive bacteria to induce DC maturation and migration is part of the armamentarium necessary for avoiding the induction of an effective cellular immune response and may explain the frequent involvement of these pathogens in chronic infections.


Subject(s)
Cell Differentiation/immunology , Cell Movement/immunology , Dendritic Cells/immunology , Dendritic Cells/microbiology , Gram-Negative Bacteria/immunology , Gram-Positive Bacteria/immunology , Pseudopodia/immunology , Toll-Like Receptor 4/physiology , Animals , Cell Adhesion/genetics , Cell Adhesion/immunology , Cell Differentiation/genetics , Dendritic Cells/cytology , Gram-Negative Bacteria/pathogenicity , Gram-Positive Bacteria/pathogenicity , Meningococcal Infections/immunology , Meningococcal Infections/microbiology , Meningococcal Infections/pathology , Mice , Mice, Inbred C57BL , Mice, Knockout , Pneumococcal Infections/immunology , Pneumococcal Infections/microbiology , Pneumococcal Infections/pathology , Pseudopodia/microbiology , Pseudopodia/pathology , Salmonella Infections, Animal/immunology , Salmonella Infections, Animal/microbiology , Salmonella Infections, Animal/pathology , Staphylococcal Infections/immunology , Staphylococcal Infections/microbiology , Staphylococcal Infections/pathology , Toll-Like Receptor 4/deficiency , Toll-Like Receptor 4/genetics
9.
PLoS Pathog ; 5(3): e1000338, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19282981

ABSTRACT

Immunoglobulin A (IgA) secretion by plasma cells in the immune system is critical for protecting the host from environmental and microbial infections. However, the molecular mechanisms underlying the generation of IgA(+) plasma cells remain poorly understood. Here, we report that the B cell-expressed tetraspanin CD37 inhibits IgA immune responses in vivo. CD37-deficient (CD37-/-) mice exhibit a 15-fold increased level of IgA in serum and significantly elevated numbers of IgA(+) plasma cells in spleen, mucosal-associated lymphoid tissue, as well as bone marrow. Analyses of bone marrow chimeric mice revealed that CD37-deficiency on B cells was directly responsible for the increased IgA production. We identified high local interleukin-6 (IL-6) production in germinal centers of CD37-/- mice after immunization. Notably, neutralizing IL-6 in vivo reversed the increased IgA response in CD37-/- mice. To demonstrate the importance of CD37-which can associate with the pattern-recognition receptor dectin-1-in immunity to infection, CD37-/- mice were exposed to Candida albicans. We report that CD37-/- mice are evidently better protected from infection than wild-type (WT) mice, which was accompanied by increased IL-6 levels and C. albicans-specific IgA antibodies. Importantly, adoptive transfer of CD37-/- serum mediated protection in WT mice and the underlying mechanism involved direct neutralization of fungal cells by IgA. Taken together, tetraspanin protein CD37 inhibits IgA responses and regulates the anti-fungal immune response.


Subject(s)
Antigens, CD/immunology , Antigens, Neoplasm/immunology , B-Lymphocytes/immunology , Cell Differentiation/immunology , Glycoproteins/immunology , Immunoglobulin A/immunology , Mycoses/immunology , Animals , Antigens, CD/genetics , Antigens, Neoplasm/genetics , B-Lymphocytes/cytology , B-Lymphocytes/metabolism , Female , Flow Cytometry , Germinal Center/immunology , Glycoproteins/genetics , Humans , Immunoglobulin A/biosynthesis , Immunohistochemistry , Interleukin-6/immunology , Interleukin-6/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Reverse Transcriptase Polymerase Chain Reaction , Tetraspanins
11.
J Cell Commun Signal ; 15(1): 25-56, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33428075

ABSTRACT

CCN2, formerly termed Connective Tissue Growth Factor, is a protein belonging to the Cellular Communication Network (CCN)-family of secreted extracellular matrix-associated proteins. As a matricellular protein it is mainly considered to be active as a modifier of signaling activity of several different signaling pathways and as an orchestrator of their cross-talk. Furthermore, CCN2 and its fragments have been implicated in the regulation of a multitude of biological processes, including cell proliferation, differentiation, adhesion, migration, cell survival, apoptosis and the production of extracellular matrix products, as well as in more complex processes such as embryonic development, angiogenesis, chondrogenesis, osteogenesis, fibrosis, mechanotransduction and inflammation. Its function is complex and context dependent, depending on cell type, state of differentiation and microenvironmental context. CCN2 plays a role in many diseases, especially those associated with fibrosis, but has also been implicated in many different forms of cancer. In the bone marrow (BM), CCN2 is highly expressed in mesenchymal stem/stromal cells (MSCs). CCN2 is important for MSC function, supporting its proliferation, migration and differentiation. In addition, stromal CCN2 supports the maintenance and longtime survival of hematopoietic stem cells, and in the presence of interleukin 7, stimulates the differentiation of pro-B lymphocytes into pre-B lymphocytes. Overexpression of CCN2 is seen in the majority of B-acute lymphoblastic leukemias, especially in certain cytogenetic subgroups associated with poor outcome. In acute myeloid leukemia, CCN2 expression is increased in MSCs, which has been associated with leukemic engraftment in vivo. In this review, the complex function of CCN2 in the BM microenvironment and in normal as well as malignant hematopoiesis is discussed. In addition, an overview is given of data on the remaining CCN family members regarding normal and malignant hematopoiesis, having many similarities and some differences in their function.

12.
Blood Adv ; 5(1): 240-249, 2021 01 12.
Article in English | MEDLINE | ID: mdl-33570642

ABSTRACT

We conducted a multicenter prospective single-arm phase 1/2 study that assesses the outcome of αß T-cell depleted allogeneic hematopoietic stem cell transplantation (allo-HSCT) of peripheral blood derived stem cells from matched related, or unrelated donors (10/10 and 9/10) in adults, with the incidence of acute graft-versus-host disease (aGVHD) as the primary end point at day 100. Thirty-five adults (median age, 59; range, 19-69 years) were enrolled. Conditioning consisted of antithymocyte globulin, busulfan, and fludarabine, followed by 28 days of mycophenolic acid after allo-HSCT. The minimal follow-up time was 24 months. The median number of infused CD34+ cells and αß T cells were 6.1 × 106 and 16.3 × 103 cells per kg, respectively. The cumulative incidence (CI) of aGVHD grades 2-4 and 3-4 at day 100 was 26% and 14%. One secondary graft failure was observed. A prophylactic donor lymphocyte infusion (DLI) (1 × 105 CD3+ T cells per kg) was administered to 54% of the subjects, resulting in a CI of aGVHD grades 2-4 and 3-4 to 37% and 17% at 2 years. Immune monitoring revealed an early reconstitution of natural killer (NK) and γδ T cells. Cytomegalovirus reactivation associated with expansion of memory-like NK cells. The CI of relapse was 29%, and the nonrelapse mortality 32% at 2 years. The 2-year CI of chronic GVHD (cGVHD) was 23%, of which 17% was moderate. We conclude that only 26% of patients developed aGVHD 2-4 after αß T-cell-depleted allo-HSCT within 100 days and was associated with a low incidence of cGVHD after 2 years. This trial was registered at www.trialregister.nl as #NL4767.


Subject(s)
Graft vs Host Disease , Hematologic Neoplasms , Hematopoietic Stem Cell Transplantation , Adult , Graft vs Host Disease/etiology , Hematologic Neoplasms/therapy , Hematopoietic Stem Cell Transplantation/adverse effects , Humans , Middle Aged , Neoplasm Recurrence, Local , Prospective Studies , T-Lymphocytes
13.
Br J Haematol ; 149(3): 322-33, 2010 May.
Article in English | MEDLINE | ID: mdl-20067561

ABSTRACT

Myelodysplastic syndromes (MDS) are a heterogeneous group of clonal haematopoietic stem cell malignancies. A subgroup, the so-called sideroblastic MDS, shows ring sideroblasts in the bone marrow aspirate that represent mitochondrial iron accumulation. Patients with sideroblastic MDS also develop systemic iron overload and generally have a low-risk MDS. Therefore it is important to understand the mechanisms responsible for iron accumulation and the associated toxicity in these patients. Recently, low levels of the iron-regulatory peptide hepcidin were found to contribute to body iron overload in beta-thalassaemia patients. A similar mechanism may account for systemic iron accumulation in sideroblastic MDS. Mitochondrial iron accumulation is observed in several subtypes of MDS, and predominantly in refractory anaemia with ring sideroblasts. The presence of ring sideroblasts is also the diagnostic hallmark in patients with inherited forms of sideroblastic anaemia. The ever-increasing insights into the affected pathways in inherited sideroblastic anaemia may lead to a better comprehension of the pathogenesis of mitochondrial iron accumulation in MDS patients. Overall, an improved understanding of the mechanisms responsible for iron overload in MDS will lead to novel treatment strategies to reduce both systemic and mitochondrial iron overload, resulting in less tissue damage and more effective erythropoiesis.


Subject(s)
Iron Overload/etiology , Myelodysplastic Syndromes/complications , Anemia, Sideroblastic/complications , Anemia, Sideroblastic/metabolism , Humans , Iron Chelating Agents/therapeutic use , Iron Overload/drug therapy , Iron Overload/metabolism , Mitochondria/metabolism , Myelodysplastic Syndromes/drug therapy , Myelodysplastic Syndromes/metabolism
14.
BMC Pharmacol ; 10: 12, 2010 Sep 13.
Article in English | MEDLINE | ID: mdl-20836839

ABSTRACT

BACKGROUND: ATP-binding cassette (ABC) transporters protect cells against unrelated (toxic) substances by pumping them across cell membranes. Earlier we showed that many ABC transporters are highly expressed in hematopoietic stem cells (HSCs) compared to more committed progenitor cells. The ABC transporter expression signature may guarantee lifelong protection of HSCs but may also preserve stem cell integrity by extrusion of agents that trigger their differentiation. Here we have studied whether non-hematopoietic stem cells (non-HSCs) exhibit a similar ABC transporter expression signature as HSCs. RESULTS: ABC transporter expression profiles were determined in non-hematopoietic stem cells (non-HSCs) from embryonic, neonatal and adult origin as well as in various mature blood cell types. Over 11,000 individual ABC transporter expression values were generated by Taqman Low Density Arrays (TLDA) to obtain a sensitivity comparable with quantitative real-time polymerase chain reactions. We found that the vast majority of transporters are significantly higher expressed in HSCs compared to non-HSCs. Furthermore, regardless their origin, non-HSCs exhibited strikingly similar ABC transporter expression profiles that were distinct from those in HSCs. Yet, sets of transporters characteristic for different stem cell types could be identified, suggesting restricted functions in stem cell physiology. Remarkably, in HSCs we could not pinpoint any single transporter expressed at an evidently elevated level when compared to all the mature blood cell types studied. CONCLUSIONS: These findings challenge the concept that individual ABC transporters are implicated in maintaining stem cell integrity. Instead, a distinct ABC transporter expression signature may be essential for stem cell function. The high expression of specific transporters in non-HSCs and mature blood cells suggests a specialized, cell type dependent function and warrants further functional experiments to determine their exact roles in cellular (patho)physiology.


Subject(s)
ATP-Binding Cassette Transporters/genetics , ATP-Binding Cassette Transporters/metabolism , Gene Expression , Hematopoietic Stem Cells/metabolism , Stem Cells/metabolism , ATP-Binding Cassette Transporters/blood , Adipose Tissue/cytology , Adult , Blood Cells/cytology , Blood Cells/metabolism , Bone Marrow Cells/cytology , Bone Marrow Cells/metabolism , Cell Differentiation , Cell Line , Fetal Blood/cytology , Flow Cytometry , Gene Expression Profiling , Hematopoiesis , Humans , Oligonucleotide Array Sequence Analysis , Osteogenesis , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain Reaction
15.
Exp Hematol ; 89: 55-60.e6, 2020 09.
Article in English | MEDLINE | ID: mdl-32781097

ABSTRACT

Despite recent identification of several prognostic markers, there is still a need for new prognostic parameters able to predict clinical outcome in chronic lymphocytic leukemia (CLL) patients. Here, we aimed to validate the prognostic ability of known (proteomic) markers measured pretreatment and to search for new proteomic markers that might be related to treatment response in CLL. To this end, baseline serum samples of 51 CLL patients treated with chemo-immunotherapy were analyzed for 360 proteomic markers, using Olink technology. Median event-free survival (EFS) was 23 months (range: 1.25-60.9). Patients with high levels of sCD23 (>11.27, p = 0.026), sCD27 (>11.03, p = 0.04), SPINT1 (>1.6, p = 0.001), and LY9 (>8.22, p = 0.0003) had a shorter EFS than those with marker levels below the median. The effect of sCD23 on EFS differed between immunoglobulin heavy chain variable gene-mutated and unmutated patients, with the shortest EFS for unmutated CLL patients with sCD23 levels above the median. Taken together, our results validate the prognostic impact of sCD23 and highlight SPINT1 and LY9 as possible promising markers for treatment response in CLL patients.


Subject(s)
Biomarkers, Tumor/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/diagnosis , Leukemia, Lymphocytic, Chronic, B-Cell/therapy , Proteinase Inhibitory Proteins, Secretory/genetics , Receptors, IgE/genetics , Signaling Lymphocytic Activation Molecule Family/genetics , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/blood , Chlorambucil , Disease-Free Survival , Female , Gene Expression , Humans , Immunoglobulin Heavy Chains/blood , Immunoglobulin Heavy Chains/genetics , Immunotherapy/methods , Lenalidomide , Leukemia, Lymphocytic, Chronic, B-Cell/genetics , Leukemia, Lymphocytic, Chronic, B-Cell/mortality , Male , Middle Aged , Mutation , Prognosis , Proteinase Inhibitory Proteins, Secretory/blood , Proteomics/methods , Receptors, IgE/blood , Rituximab , Signaling Lymphocytic Activation Molecule Family/blood , Treatment Outcome , Tumor Necrosis Factor Receptor Superfamily, Member 7/blood , Tumor Necrosis Factor Receptor Superfamily, Member 7/genetics
16.
Exp Hematol ; 36(7): 860-70, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18375037

ABSTRACT

The C-type lectins DC-SIGN (CD209) and L-SIGN (CD299) recognize defined carbohydrates expressed on pathogens and cells. Those lectins are expressed on dendritic cells (DC) and/or on liver-sinusoidal endothelial cells. Both cell types modulate immune responses. In acute lymphoblastic leukemia (ALL), aberrant glycosylation of blast cells can alter their interaction with the C-type lectins DC-SIGN and L-SIGN, thereby affecting their immunological elimination. We investigated whether recombinant DC-SIGN and L-SIGN bind to blood or bone marrow cells from B- and T-ALL patients and compared that with binding of peripheral blood lymphocytes from healthy donors. It was found that increased binding of ALL cells to DC-SIGN and L-SIGN was observed compared to cells from healthy donors. Furthermore, L-SIGN bound a higher percentage of leukemic and normal cells than DC-SIGN. B-ALL bone marrow cells showed the highest binding to L-SIGN. DC-SIGN bound equally well to B-ALL and T-ALL cells. Within ALL subtypes, DC-SIGN binding was higher with mature T-ALL. Interestingly, our data demonstrate that increased binding of DC-SIGN and L-SIGN to peripheral leukemic cells from B-ALL patients is associated with poor survival. These data demonstrate that high binding of B-ALL peripheral blood cells to DC-SIGN and L-SIGN correlates with poor prognosis. Apparently, when B-ALL cells enter the blood circulation and are able to interact with DC-SIGN and L-SIGN the immune response is shifted toward tolerance. Additional studies are necessary to ascertain the possible role of these results in terms of disease pathogenesis and their potential as target to eradicate leukemic cells.


Subject(s)
Burkitt Lymphoma/immunology , Cell Adhesion Molecules/immunology , Dendritic Cells/immunology , Immune Tolerance , Lectins, C-Type/immunology , Leukemia-Lymphoma, Adult T-Cell/immunology , Receptors, Cell Surface/immunology , Adolescent , Adult , Bone Marrow Cells/immunology , Bone Marrow Cells/pathology , Burkitt Lymphoma/mortality , Burkitt Lymphoma/pathology , Carbohydrates/immunology , Child , Child, Preschool , Dendritic Cells/pathology , Disease-Free Survival , Endothelial Cells/immunology , Endothelial Cells/pathology , Female , Glycosylation , Humans , Leukemia-Lymphoma, Adult T-Cell/mortality , Leukemia-Lymphoma, Adult T-Cell/pathology , Liver/immunology , Liver/pathology , Male , Middle Aged , Protein Binding/immunology , Survival Rate
17.
Clin Lymphoma Myeloma Leuk ; 19(10): 624-634, 2019 10.
Article in English | MEDLINE | ID: mdl-31427260

ABSTRACT

BACKGROUND: Ruxolitinib is an approved treatment for myelofibrosis patients, but data regarding patients with baseline thrombocytopenia are limited. The EXPAND study recently suggested tolerability of ruxolitinib, with a maximum starting dose of 10 mg 2 times a day (BID). However, the small sample size and vigorous follow-up in this trial hamper direct translation of these results to routine practice. PATIENTS AND METHODS: We report retrospective data on Dutch ruxolitinib-treated myelofibrosis patients, focusing on those with baseline thrombocytopenia. Additionally, we reviewed current literature regarding ruxolitinib treatment in this subgroup. RESULTS: In our cohort, 12 of 119 patients had a baseline platelet count of < 100 × 109/L. Spleen responses at a mean treatment duration of 25 weeks were documented in 1 of 6 and 15 of 47 patients with and without baseline thrombocytopenia, respectively. Despite a high rate of grade 3 or higher thrombocytopenia in thrombocytopenic versus nonthrombocytopenic patients (42% vs. 15%), no grade 3 or higher hemorrhage was reported. Median doses in thrombocytopenic patients were 15 and 10 mg BID at the start and after 12 weeks of treatment, respectively. Additionally, 238 thrombocytopenic patients were identified in the available literature, of whom 59 were treated in routine practice. Incidences of severe thrombocytopenia reported separately for patients with baseline thrombocytopenia were 30% to 59% (grade 3 or higher) and 4% to 60% (grade 4). Severe bleeding, pooled across our data and evaluable studies, occurred in 2.4%. CONCLUSION: Ruxolitinib treatment appears to be safe for patients with platelet counts of 50 to 100 × 109/L in real-life practice. We did not find any reason to discourage a starting dose of 10 mg BID in this subgroup.


Subject(s)
Janus Kinase 2/antagonists & inhibitors , Primary Myelofibrosis/drug therapy , Pyrazoles/therapeutic use , Thrombocytopenia/diagnosis , Adult , Aged , Aged, 80 and over , Female , Humans , Janus Kinase 2/metabolism , Male , Middle Aged , Netherlands , Nitriles , Platelet Count , Primary Myelofibrosis/blood , Pyrazoles/adverse effects , Pyrimidines , Retrospective Studies , Thrombocytopenia/blood , Thrombocytopenia/chemically induced
18.
Br J Haematol ; 141(6): 799-807, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18410452

ABSTRACT

Minor histocompatibility antigens (MiHA) selectively expressed by haematopoietic cells are attractive targets for specific immunotherapy after allogeneic stem cell transplantation (SCT). Previously, we described LRH-1 as a haematopoietic-lineage restricted MiHA that is capable of eliciting an allogeneic cytotoxic T-lymphocyte (CTL) response after SCT and donor lymphocyte infusion. Importantly, the gene encoding LRH-1, P2X5, is not expressed in prominent graft-versus-host-disease target tissues such as skin, liver and gut. Here, we investigate whether LRH-1-specific immunotherapy may be exploited for the treatment of lymphoid malignancies. We examined P2X5 mRNA expression in a large panel of patient samples and cell lines from different types of lymphoid malignancies by real-time quantitative reverse transcription polymerase chain reaction. P2X5 mRNA was highly expressed in malignant cells from all stages of lymphoid development. Furthermore, all LRH-1-positive lymphoid tumour cell lines were susceptible to LRH-1 CTL-mediated lysis in flow cytometry-based cytotoxicity assays. However, interferon-gamma production was low or absent after stimulation with some cell lines, possibly due to differences in activation thresholds for CTL effector functions. Importantly, primary cells from patients with lymphoid malignancies were effectively lysed by LRH-1-specific CTL. These findings indicate that MiHA LRH-1 is a potential therapeutic target for cellular immunotherapy of lymphoid malignancies.


Subject(s)
DNA-Binding Proteins/immunology , Leukemia, Lymphoid/immunology , Lymphoma, Non-Hodgkin/immunology , Receptors, Purinergic P2/biosynthesis , T-Lymphocytes, Cytotoxic/immunology , Transcription Factors/immunology , Cytotoxicity, Immunologic/immunology , Humans , Leukemia, Lymphoid/pathology , Lymphoma, Non-Hodgkin/pathology , Multiple Myeloma/immunology , Multiple Myeloma/pathology , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , RNA, Messenger/genetics , RNA, Neoplasm/genetics , Receptors, Purinergic P2/genetics , Receptors, Purinergic P2X5 , Reverse Transcriptase Polymerase Chain Reaction/methods , Tumor Cells, Cultured
19.
Amyloid ; 25(4): 227-233, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30513220

ABSTRACT

BACKGROUND: Although survival has improved in recent decades, the short-term prognosis of patients with immunoglobulin light chain (AL) amyloidosis remains grim. We aimed to assess overall survival (OS) of AL amyloidosis patients by comparing cohorts in two consecutive time periods. METHODS: Data were collected and compared on 126 patients from two tertiary referral centres in The Netherlands during the time periods 2008-2012 and 2013-2016. RESULTS: There was a non-significant trend to improved 6-month OS in the last cohort (78% vs. 67%, p = .216, crude odds ratio 1.66, 95%CI 0.74-3.70, adjusted odds ratio 2.22, 95%CI 0.88-5.56). Patients in this cohort had higher Mayo risk scores (stage III 40% vs. 24%, p < .001 and revised stage IV 14% vs. 11%, p < .001), higher use of bortezomib (50% vs. 30%), and better haematological response (complete response/very good partial response in 39% vs. 27%, p < .001). Diagnostic delay was similar in both time periods. CONCLUSIONS: In the 2013-2016 cohort there was a trend toward improved 6-month OS, and an improved haematological response. Patients in this cohort had more advanced cardiac disease and received bortezomib more frequently, but diagnostic delay was similar to the 2008-2012 cohort. For further prognostic improvement, practitioners should be more alert, especially for cardiac amyloidosis.


Subject(s)
Antineoplastic Agents/therapeutic use , Biomarkers/analysis , Bortezomib/therapeutic use , Hematologic Tests , Immunoglobulin Light-chain Amyloidosis/mortality , Aged , Aged, 80 and over , Cohort Studies , Female , Follow-Up Studies , Humans , Immunoglobulin Light-chain Amyloidosis/diagnosis , Immunoglobulin Light-chain Amyloidosis/drug therapy , Male , Middle Aged , Prognosis , Survival Rate
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