| 1. |
- Au, A. E., et al.
(författare)
-
Proinflammatory microenvironment promotes lymphoma progression in mice with high megakaryocyte and TPO levels
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:8, s. 1560-1571
-
Tidskriftsartikel (refereegranskat)abstract
- Platelets have been shown to enhance the survival of lymphoma cell lines, but it is unclear if they play a role in lymphoma. Here we investigate a potential role for platelets and/or megakaryocytes in Eµ-myc lymphoma progression. Eµ-myc tumour cells were transplanted into recipient wild-type control mice, Mpl-/-, or TpoTg mice, which exhibit normal, low and high platelet and megakaryocyte counts, respectively. Transplanted TpoTg mice exhibited enhanced lymphoma progression with increased WBC counts, spleen and lymph node weights and enhanced liver infiltration when compared to wild-type. Conversely, tumour bearing Mpl-/- mice presented with reduced WBC counts, lymph node weights and less liver infiltration when compared to wild-type. Utilizing a Mpl-deficient thrombocytopenic immunocompromised mouse model, our results were confirmed with the human NHL GRANTA cell line. While we found that platelets and platelet released molecules supported Eµ-myc tumour cell survival in vitro, pharmacological inhibition of platelet function or anticoagulation in Eµ-myc transplanted wild-type mice did not improve disease outcome. Furthermore, transient platelet depletion or sustained Bcl-xL dependent thrombocytopenia did not alter lymphoma progression. Cytokine analysis of the bone marrow fluid microenvironment revealed increased levels of the proinflammatory molecule interleukin (IL)-1 in TpoTg mice, whereas levels were lowered in Mpl-/- mice. Moreover, RNA sequencing of blood-resident Eµ-myclymphoma cells from TpoTgand wild-type mice after tumour transplant revealed upregulation of hallmark gene sets associated with inflammatory response in TpoTg mice. We propose that a pro-inflammatory microenvironment in TpoTgmice promoted lymphoma progression.
|
|
| 2. |
- Bonfiglio, Silvia, et al.
(författare)
-
BTK and PLCG2 remain unmutated in one-third of patients with CLL relapsing on ibrutinib
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:12, s. 2794-2806
-
Tidskriftsartikel (refereegranskat)abstract
- Patients with chronic lymphocytic leukemia (CLL) progressing on ibrutinib constitute an unmet need. Though Bruton tyrosine kinase (BTK) and PLCG2 mutations are associated with ibrutinib resistance, their frequency and relevance to progression are not fully understood. In this multicenter retrospective observational study, we analyzed 98 patients with CLL on ibrutinib (49 relapsing after an initial response and 49 still responding after ≥1 year of continuous treatment) using a next-generation sequencing (NGS) panel (1% sensitivity) comprising 13 CLL-relevant genes including BTK and PLCG2. BTK hotspot mutations were validated by droplet digital polymerase chain reaction (ddPCR) (0.1% sensitivity). By integrating NGS and ddPCR results, 32 of 49 relapsing cases (65%) carried at least 1 hotspot BTK and/or PLCG2 mutation(s); in 6 of 32, BTK mutations were only detected by ddPCR (variant allele frequency [VAF] 0.1% to 1.2%). BTK/PLCG2 mutations were also identified in 6 of 49 responding patients (12%; 5/6 VAF <10%), of whom 2 progressed later. Among the relapsing patients, the BTK-mutated (BTKmut) group was enriched for EGR2 mutations, whereas BTK-wildtype (BTKwt) cases more frequently displayed BIRC3 and NFKBIE mutations. Using an extended capture-based panel, only BRAF and IKZF3 mutations showed a predominance in relapsing cases, who were enriched for del(8p) (n = 11; 3 BTKwt). Finally, no difference in TP53 mutation burden was observed between BTKmut and BTKwt relapsing cases, and ibrutinib treatment did not favor selection of TP53-aberrant clones. In conclusion, we show that BTK/PLCG2 mutations were absent in a substantial fraction (35%) of a real-world cohort failing ibrutinib, and propose additional mechanisms contributing to resistance.
|
|
| 3. |
- Borg Hammer, Anne Sofie, et al.
(författare)
-
Hypodiploidy has unfavorable impact on survival in pediatric acute myeloid leukemia : An I-BFM Study Group collaboration
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:6, s. 1045-1055
-
Tidskriftsartikel (refereegranskat)abstract
- Hypodiploidy, defined as modal numbers (MNs) 45 or lower, has not been independently investigated in pediatric acute myeloid leukemia (AML) but is a well-described high-risk factor in pediatric acute lymphoblastic leukemia. We aimed to characterize and study the prognostic impact of hypodiploidy in pediatric AML. In this retrospective cohort study, we included children below 18 years of age with de novo AML and a hypodiploid karyotype diagnosed from 2000 to 2015 in 14 childhood AML groups from the International Berlin-Frankfurt-Münster (I-BFM) framework. Exclusion criteria comprised constitutional hypodiploidy, monosomy 7, composite karyotype, and t(8;21) with concurring sex chromosome loss. Hypodiploidy occurred in 81 patients (1.3%) with MNs, 45 (n = 66); 44 (n = 10) and 43 (n = 5). The most frequently lost chromosomes were chromosome 9 and sex chromosomes. Five-year event-free survival (EFS) and overall survival (OS) were 34% and 52%, respectively, for the hypodiploid cohort. Children with MN≤44 (n = 15) had inferior EFS (21%) and OS (33%) compared with children with MN = 45 (n = 66; EFS, 37%; OS, 56%). Adjusted hazard ratios (HRs) were 4.9 (P = .001) and 6.1 (P = .003). Monosomal karyotype or monosomy 9 had particular poor OS (43% and 15%, respectively). Allogeneic stem cell transplantation (SCT) in first complete remission (CR1) (n = 18) did not mitigate the unfavorable outcome of hypodiploidy (adjusted HR for OS was 1.5; P = .42). We identified pediatric hypodiploid AML as a rare subgroup with an inferior prognosis even in the patients treated with SCT in CR1.
|
|
| 4. |
- Ekberg, Sara, et al.
(författare)
-
Late effects in patients with mantle cell lymphoma treated with or without autologous stem cell transplantation
- 2023
-
Ingår i: Blood Advances. - : Elsevier. - 2473-9529 .- 2473-9537. ; 7:5, s. 866-874
-
Tidskriftsartikel (refereegranskat)abstract
- Studies on late effects in patients with mantle cell lymphoma (MCL) are becoming increasingly important as survival is improving, and novel targeted drugs are being introduced. However, knowledge about late effects is limited. The aim of this population-based study was to describe the magnitude and panorama of late effects among patients treated with or without high-dose chemotherapy with autologous stem cell transplantation (HD-ASCT). The study cohort included all patients with MCL, recorded in the Swedish Lymphoma Register, aged 18 to 69 years, diagnosed between 2000 and 2014 (N = 620; treated with HD-ASCT, n = 247) and 1:10 matched healthy comparators. Patients and comparators were followed up via the National Patient Register and Cause of Death Register, from 12 months after diagnosis or matching to December 2017. Incidence rate ratios of the numbers of outpatient visits, hospitalizations, and bed days were estimated using negative binomial regression models. In relation to the matched comparators, the rate of specialist and hospital visits was significantly higher among patients with MCL. Patients with MCL had especially high relative risks of infectious, respiratory, and blood disorders. Within this observation period, no difference in the rate of these complications, including secondary neoplasms, was observed between patients treated with and without HD-ASCT. Most of the patients died from their lymphoma and not from another cause or treatment complication. Taken together, our results imply that most of the posttreatment health care needs are related to the lymphoma disease itself, thus, indicating the need for more efficient treatment options.
|
|
| 5. |
- Ingason, A. B., et al.
(författare)
-
Comparison of the effectiveness and safety of direct oral anticoagulants: a nationwide propensity score-weighted study
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:11, s. 2564-2572
-
Tidskriftsartikel (refereegranskat)abstract
- In the pivotal randomized controlled trials (RCTs) for patients with atrial fibrillation, direct oral anticoagulants (DOACs) had similar or even superior efficacy and safety compared with warfarin. However, RCTs comparing different DOACs are nonexistent and previous observational studies have yielded conflicting results. In this nationwide cohort study, rates of any stroke or systemic embolism (stroke/SE) and major bleeding were compared among new users of apixaban, dabigatran, and rivaroxaban with atrial fibrillation from 2014 to 2019. Inverse probability weighting was used to yield balanced study groups, and outcomes were compared using Cox regression. Stroke/SE rates were similar in patients receiving apixaban, dabigatran, and rivaroxaban. Dabigatran was associated with twofold higher rates of myocardial infarction (MI) than rivaroxaban (1.4 events/100 person-years (py) vs 0.7 events/100-py, hazard ratio [HR] 2.21, 95% confidence interval [CI], 1.00-4.90) and apixaban (1.4 events/100-py vs 0.7 events/100-py, HR 2.26, 95% CI, 0.90-5.67), although the second comparison included the possibility of a null effect. Rivaroxaban was associated with higher major bleeding rates compared with apixaban (2.9 events/100-py vs 1.8 events/ 100-py, HR 1.64, 95% CI, 1.13-2.37) and dabigatran (2.9 events/100-py vs 1.4 events/100-py, HR 2.18, 95% CI, 1.21-3.93). Specifically, rivaroxaban had higher rates of major gastrointestinal bleeding and other major bleeding than apixaban. In conclusion, although stroke/SE rates were similar for DOACs, rivaroxaban was associated with higher rates of major bleeding than other DOACs and lower rates of MI than dabigatran. These results may help guide oral anticoagulant selection, especially in patients at high risk of bleeding or MI.
|
|
| 6. |
- Kemps, PG, et al.
(författare)
-
Clinicogenomic associations in childhood Langerhans cell histiocytosis: an international cohort study
- 2023
-
Ingår i: Blood advances. - : American Society of Hematology. - 2473-9537 .- 2473-9529. ; 7:4, s. 664-679
-
Tidskriftsartikel (refereegranskat)abstract
- Langerhans cell histiocytosis (LCH) is a rare neoplastic disorder caused by somatic genetic alterations in hematopoietic precursor cells differentiating into CD1a+/CD207+ histiocytes. LCH clinical manifestation is highly heterogeneous. BRAF and MAP2K1 mutations account for ∼80% of genetic driver alterations in neoplastic LCH cells. However, their clinical associations remain incompletely understood. Here, we present an international clinicogenomic study of childhood LCH, investigating 377 patients genotyped for at least BRAFV600E. MAPK pathway gene alterations were detected in 300 (79.6%) patients, including 191 (50.7%) with BRAFV600E, 54 with MAP2K1 mutations, 39 with BRAF exon 12 mutations, 13 with rare BRAF alterations, and 3 with ARAF or KRAS mutations. Our results confirm that BRAFV600E associates with lower age at diagnosis and higher prevalence of multisystem LCH, high-risk disease, and skin involvement. Furthermore, BRAFV600E appeared to correlate with a higher prevalence of central nervous system (CNS)–risk bone lesions. In contrast, MAP2K1 mutations associated with a higher prevalence of single-system (SS)-bone LCH, and BRAF exon 12 deletions seemed to correlate with more lung involvement. Although BRAFV600E correlated with reduced event-free survival in the overall cohort, neither BRAF nor MAP2K1 mutations associated with event-free survival when patients were stratified by disease extent. Thus, the correlation of BRAFV600E with inferior clinical outcome is (primarily) driven by its association with disease extents known for high rates of progression or relapse, including multisystem LCH. These findings advance our understanding of factors underlying the remarkable clinical heterogeneity of LCH but also question the independent prognostic value of lesional BRAFV600E status.
|
|
| 7. |
- Kennedy, Vanessa E., et al.
(författare)
-
Mast cell leukemia : clinical and molecular features and survival outcomes of patients in the ECNM Registry
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:9, s. 1713-1724
-
Tidskriftsartikel (refereegranskat)abstract
- Mast cell leukemia (MCL) is a rare subtype of systemic mastocytosis defined by >= 20% mast cells (MC) on a bone marrow aspirate. We evaluated 92 patients with MCL from the European Competence Network on Mastocytosis registry. Thirty-one (34%) patients had a diagnosis of MCL with an associated hematologic neoplasm (MCL-AHN). Chronic MCL (lack of C-findings) comprised 14% of patients, and only 4.5% had "leukemic MCL" (>= 10% circulating MCs). KIT D816V was found in 62/85 (73%) evaluable patients; 9 (11%) individuals exhibited alternative KIT mutations, and no KIT variants were detected in 14 (17%) subjects. Ten evaluable patients (17%) had an abnormal karyotype and the poor-risk SRSF2, ASXL1, and RUNX1 (S/A/R) mutations were identified in 16/36 (44%) patients who underwent next-generation sequencing. Midostaurin was the most common therapy administered to 65% of patients and 45% as first-line therapy. The median overall survival (OS) was 1.6 years. In multivariate analysis (S/A/R mutations excluded owing to low event rates), a diagnosis of MCL-AHN (hazard ratio [HR], 4.7; 95% confidence interval [CI], 1.7-13.0; P = .001) and abnormal karyotype (HR, 5.6; 95% CI, 1.4-13.3; P = .02) were associated with inferior OS; KIT D816V positivity (HR, 0.33; 95% CI, 0.11-0.98; P = .04) and midostaurin treatment (HR, 0.32; 95% CI, 0.08-0.72; P = .008) were associated with superior OS. These data provide the most comprehensive snapshot of the clinicopathologic, molecular, and treatment landscape of MCL to date, and should help further inform subtyping and prognostication of MCL.
|
|
| 8. |
- Mannes, Marco, et al.
(författare)
-
Complement and platelets : prothrombotic cell activation requires membrane attack complex-induced release of danger signals
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:20, s. 6367-6380
-
Tidskriftsartikel (refereegranskat)abstract
- Complement activation in the diseases paroxysmal nocturnal hemoglobinuria (PNH) and atypical hemolytic uremic syndrome (aHUS) results in cytolysis and fatal thrombotic events, which are largely refractory to anticoagulation and/or antiplatelet therapy. Anticomplement therapy, however, efficiently prevents thrombotic events in PNH and aHUS, but the underlying mechanisms remain unresolved. We show that complement-mediated hemolysis in whole blood induces platelet activation similarly to activation by adenosine 5 '-diphosphate (ADP). Blockage of C3 or C5 abolished platelet activation. We found that human platelets failed to respond functionally to the anaphylatoxins C3a and C5a. Instead, complement activation did lead to prothrombotic cell activation in the whole blood when membrane attack complex (MAC)-mediated cytolysis occurred. Consequently, we demonstrate that ADP receptor antagonists efficiently inhibited platelet activation, although full complement activation, which causes hemolysis, occurred. By using an established model of mismatched erythrocyte transfusions in rats, we crossvalidated these findings in vivo using the complement inhibitor OmCI and cobra venom factor. Consumptive complement activation in this animal model only led to a thrombotic phenotype when MAC-mediated cytolysis occurred. In conclusion, complement activation only induces substantial prothrombotic cell activation if terminal pathway activation culminates in MAC-mediated release of intracellular ADP. These results explain why anticomplement therapy efficiently prevents thromboembolisms without interfering negatively with hemostasis.
|
|
| 9. |
- Naeem, Aishath, et al.
(författare)
-
Pirtobrutinib targets BTK C481S in ibrutinib-resistant CLL but second-site BTK mutations lead to resistance
- 2023
-
Ingår i: Blood Advances. - : American Society of Hematology. - 2473-9529 .- 2473-9537. ; 7:9, s. 1929-1943
-
Tidskriftsartikel (refereegranskat)abstract
- Covalent inhibitors of Bruton tyrosine kinase (BTK) have transformed the therapy of chronic lymphocytic leukemia (CLL), but continuous therapy has been complicated by the development of resistance. The most common resistance mechanism in patients whose disease progresses on covalent BTK inhibitors (BTKis) is a mutation in the BTK 481 cysteine residue to which the inhibitors bind covalently. Pirtobrutinib is a highly selective, noncovalent BTKi with substantial clinical activity in patients whose disease has progressed on covalent BTKi, regardless of BTK mutation status. Using in vitro ibrutinib-resistant models and cells from patients with CLL, we show that pirtobrutinib potently inhibits BTK-mediated functions including B-cell receptor (BCR) signaling, cell viability, and CCL3/CCL4 chemokine production in both BTK wild-type and C481S mutant CLL cells. We demonstrate that primary CLL cells from responding patients on the pirtobrutinib trial show reduced BCR signaling, cell survival, and CCL3/CCL4 chemokine secretion. At time of progression, these primary CLL cells show increasing resistance to pirtobrutinib in signaling inhibition, cell viability, and cytokine production. We employed longitudinal whole-exome sequencing on 2 patients whose disease progressed on pirtobrutinib and identified selection of alternative-site BTK mutations, providing clinical evidence that secondary BTK mutations lead to resistance to noncovalent BTKis.
|
|
| 10. |
- Nannya, Y, et al.
(författare)
-
Postazacitidine clone size predicts long-term outcome of patients with myelodysplastic syndromes and related myeloid neoplasms
- 2023
-
Ingår i: Blood advances. - : American Society of Hematology. - 2473-9537 .- 2473-9529. ; 7:14, s. 3624-3636
-
Tidskriftsartikel (refereegranskat)abstract
- Azacitidine is a mainstay of therapy for MDS-related diseases. The purpose of our study is to elucidate the effect of gene mutations on hematological response and overall survival (OS), particularly focusing on their post-treatment clone size. We enrolled a total of 449 patients with MDS or related myeloid neoplasms. They were analyzed for gene mutations in pre- (n=449) and post- (n=289) treatment bone marrow samples using targeted-capture sequencing to assess the impact of gene mutations and their post-treatment clone size on treatment outcomes. In Cox proportional hazard modeling, multi-hit TP53 mutation (HR, 2.03; 95% CI, 1.42-2.91; P<.001), EZH2 mutation (HR, 1.71; 95% CI, 1.14-2.54; P=.009), and DDX41 mutations (HR, 0.33; 95% CI, 0.17-0.62; P<.001), together with age, high-risk karyotypes, low platelet, and high blast counts, independently predicted OS. Post-treatment clone size accounting for all drivers significantly correlated with International Working Group (IWG)-response (P<.001, trend test), except for that of DDX41-mutated clones, which did not predict IWG-response. Combined, IWG-response and post-treatment clone size further improved the prediction of the original model and even that of a recently proposed molecular prediction model, IPSS-M (c-index, 0.653 vs 0.688; P<.001, likelihood ratio test). In conclusion, evaluation of post-treatment clone size, together with pre-treatment mutational profile as well as IWG-response have a role in better prognostication of azacitidine-treated myelodysplasia patients.
|
|
