Polyploidization resulted from massive DNA synthesis is crucial for megakaryocyte maturation, while the regulatory mechanisms of cell fitness upon this special cellular process remain poorly understood. Here, we reveal t...Polyploidization resulted from massive DNA synthesis is crucial for megakaryocyte maturation, while the regulatory mechanisms of cell fitness upon this special cellular process remain poorly understood. Here, we reveal that glutamine synthetase (GLUL) facilitates thrombocytopoiesis by restricting ammonia accumulation during polyploidization. GLUL is found to be distinctly expressed in platelet-producing megakaryocytes and increasingly elevated with the progression of polyploidization, and GLUL deficiency impairs megakaryocyte maturation and platelet production. Mechanistically, GLUL detoxifies ammonia derived from adenosine deaminase acting on RNA 1 (ADAR1)-mediated double-stranded RNA (dsRNA) editing in megakaryocytes undergoing polyploidization. Ammonia accumulation is observed in megakaryocytes defective in GLUL, leading to lysosomal and mitochondrial damage and even cell death. Fulvotomentoside A (FtA) is identified as a potential GLUL agonist with the capacity to promote thrombocytopoiesis in mice after radiation and chemotherapy injury. Our findings uncover the biological significance of GLUL in megakaryocyte maturation and provide a new avenue for regulating thrombocytopoiesis.
Hourigan CS, Beugelink L, Othman J
… +18 more, Gui G, Ivey A, Dillon RJ, Thiede C, Levis MJ, Dillon LW, Wei AH, Tiong IS, Loo S, Döhner K, Arnhardt I, Kowalik A, Potter N, Kim DDH, Preudhomme C, Duployez N, Heuser M, Valk PJ
FLT3-ITD measurable residual disease (MRD) testing for patients in remission from acute myeloid leukemia (AML) is now recommended by the recently updated clinical standard of care guidelines. This companion technical not...FLT3-ITD measurable residual disease (MRD) testing for patients in remission from acute myeloid leukemia (AML) is now recommended by the recently updated clinical standard of care guidelines. This companion technical note provides important laboratory and clinical recommendations regarding such testing.
Abramson JS, Siddiqi T, Gordon LI
… +16 more, Lunning MA, Wang M, Arnason JE, Kamdar M, Maloney DG, Shadman M, Andreadis CB, Sehgal A, Solomon SR, Ghosh N, Hidalgo-López JE, Wang J, Ding X, Ogasawara K, Singh A, Palomba ML
We present 5-year survival results in patients with R/R LBCL from TRANSCEND NHL 001 (TRANSCEND), including data from the separate long-term follow-up (LTFU) study. Overall, 345 patients were leukapheresed, 270 received l...We present 5-year survival results in patients with R/R LBCL from TRANSCEND NHL 001 (TRANSCEND), including data from the separate long-term follow-up (LTFU) study. Overall, 345 patients were leukapheresed, 270 received liso-cel, and 257 were efficacy evaluable. Among efficacy-evaluable patients, median overall survival (OS) was 27.5 months (95% confidence interval [CI], 16.2‒47.3; leukapheresed set, 15.2 months [95% CI, 11.5‒23.4]) with estimated 5-year OS rate of 38% (95% CI, 32‒45; leukapheresed set, 33% [95% CI, 28‒39]). Median disease-specific survival (DSS; excludes deaths unrelated to disease progression) was 67.8 months (95% CI, 23.5‒not reached [NR]; leukapheresed set, 27.4 months [95% CI, 14.4‒69.7]) with estimated 5-year DSS rate of 52% (95% CI, 45‒59; leukapheresed set, 47% [95% CI, 41‒52]). Among efficacy-evaluable patients from TRANSCEND who were alive at end-of-study and enrolled in the LTFU (n=84), median OS and DSS were NR (95% CI, NR‒NR) and estimated 5-year OS and DSS rates were 78% (95% CI, 67‒86) and 92% (95% CI, 84‒97), respectively. Most deaths occurred ≤2 years after infusion; no new safety signals were observed with low rates of late severe infections and second primary malignancies. These data support the curative potential of liso-cel in patients with R/R LBCL. Clinicaltrials.gov: NCT02631044, NCT03435796.
Deletion of 17p is among the most adverse cytogenetic abnormalities in multiple myeloma (MM). By integrating RNA-seq data from patient MM cells with genetic dependency data from MM cell lines, we identified the protein k...Deletion of 17p is among the most adverse cytogenetic abnormalities in multiple myeloma (MM). By integrating RNA-seq data from patient MM cells with genetic dependency data from MM cell lines, we identified the protein kinase membrane-associated tyrosine/threonine 1 (PKMYT1) kinase, a member of the Wee family, as a potential therapeutic target in MM cells harboring del(17p). Genetic suppression or pharmacological inhibition of PKMYT1 activity with the selective inhibitor RP-6306 triggered accumulation of DNA damage, micronucleus formation and mitotic catastrophe, resulting in preferential cell death in del(17p) MM cells while largely sparing del(17p)-negative MM cells and healthy cells. RP-6306 also reduced tumor burden and extended survival in vivo in both xenograft and TP53-deficient syngeneic models. Collectively, our findings nominate PKMYT1 as an actionable target and support PKMYT1 inhibition as a biomarker-driven therapeutic strategy for patients with del(17p)/TP53-deficient MM.
Histidine-rich glycoprotein (HRG) is a 75-kDa plasma protein produced by the liver and circulating at about 2 µM, with an additional pool in platelets that is released upon activation. Previously, we demonstrated that HR...Histidine-rich glycoprotein (HRG) is a 75-kDa plasma protein produced by the liver and circulating at about 2 µM, with an additional pool in platelets that is released upon activation. Previously, we demonstrated that HRG downregulates the contact system by binding polyanions and reducing their capacity to activate factor (F) XII. Although HRG localizes on the platelet surface, its role in platelet biology remains uncertain. Accordingly, we investigated whether HRG directly engages platelet receptors to regulate adhesion and aggregation. Using human and murine platelets, we show that HRG (a) binds to glycoprotein (GP)Ibα on resting and activated platelets and to GPIIb/IIIa on activated platelets, (b) competes with von Willebrand factor (VWF) for binding to GPIbα on resting platelets and with fibrinogen for binding to GPIIb/IIIa on activated platelets, and (c) attenuates platelet agglutination, aggregation, and platelet-mediated thrombus growth. Furthermore, in an endothelial-platelet flow system or a collagen-coated microperfusion chamber, HRG reduced VWF-mediated platelet string formation and attenuated platelet deposition under high-shear conditions. Plasma HRG levels in patients with sepsis or COVID-19 were about half those of healthy controls, and reducing HRG to these levels in vitro promoted a hyperreactive platelet phenotype. Therefore, HRG not only modulates coagulation but also platelet adhesion and aggregation by competing with VWF and fibrinogen for binding to GPIbα and GPIIb/IIIa.
Esrick EB, Lehmann L, Federico A
… +24 more, Vincon H, Liu B, Daley H, Dansereau C, De Oliveira S, Everett JK, Kao PC, Moore TB, Morris E, Trebeden-Negre H, Shaw KL, Roach GD, Ritz J, Roche AM, Silva O, Grant PE, Bushman FD, Kohn DB, Jain A, London WB, Justus DG, Armant M, Manis JP, Williams DA
Sickle cell disease (SCD) is characterized by chronic hemolysis, painful vaso-occlusive episodes (VOE) and end organ damage. High levels of fetal hemoglobin (HbF) attenuate the disease phenotype. We used a lentivirus vec...Sickle cell disease (SCD) is characterized by chronic hemolysis, painful vaso-occlusive episodes (VOE) and end organ damage. High levels of fetal hemoglobin (HbF) attenuate the disease phenotype. We used a lentivirus vector (LVV) expressing an shRNA embedded in a microRNA (shmiR) targeting BCL11A in erythrocytes to induce HbF in a first-in-human pilot study in SCD. The purpose of the study was to assess hematopoietic stem/progenitor cells (HSPCs) collection, transduction parameters, safety, HbF induction and durability. Eleven eligible patients with SCD had HSC collection. Plerixafor-mobilized peripheral blood HSCs required for manufacturing were obtained in one mobilization cycle for 10/11 subjects and 11/11 patient products were successfully manufactured with a median time to release of product of 39 days. Ten patients were infused with autologous HSCs transduced with the shmiR vector. Engraftment occurred in all 10 patients. With a median follow-up of 58 months (range: 35-82) after infusion, no adverse events attributed to the gene vector have occurred. Transduction efficiency was 93.1%. One patient demonstrated low engraftment of transduced cells and had suboptimal HbF induction. In the remaining 9 patients, at 2 years post-treatment peripheral blood demonstrated 71% F cells with 11.9 pg HbF/F cells, both stable in 9 patients with ≥48 months follow-up. All patients who had VOEs prior to gene therapy demonstrated sustained mitigation of pain events. These data demonstrate excellent manufacturing efficiency and safety, with efficacy of targeting BCL11A using a shmiR LVV, and long-term durability of the shmiR vector, leading to a pivotal multi-site phase 2 trial currently underway (NCT05353647).
Bal S, Htut M, Nadeem O
… +18 more, Anderson LD, Gregory T, Kocoglu M, Rossi AC, Martin TG, Egan DN, Costa LJ, Hu H, Chen J, Li S, Kelly LM, Sarkis N, Ziyad S, Jordahl KM, Kao WM, Kaeding AJ, Burgess MR, Berdeja JG
Patients with relapsed/refractory multiple myeloma (RRMM) have limited treatment options. Arlocabtagene autoleucel (arlo-cel, BMS-986393) is an autologous chimeric antigen receptor (CAR) T-cell therapy targeting G protei...Patients with relapsed/refractory multiple myeloma (RRMM) have limited treatment options. Arlocabtagene autoleucel (arlo-cel, BMS-986393) is an autologous chimeric antigen receptor (CAR) T-cell therapy targeting G protein-coupled receptor class C group 5 member D (GPRC5D). This phase 1, dose-escalation/expansion study (NCT04674813) enrolled adult patients with RRMM and ≥3 prior antimyeloma treatment regimens, including an immunomodulatory drug (IMiD), a proteasome inhibitor, and an anti-CD38 antibody. At baseline, patients (N=84) had a median of 5 prior regimens and 49% had previously received BCMA-targeted therapy, of whom 38% received CAR T-cell therapy. Arlo-cel was administered as a one-time intravenous infusion of 25×106-450×106 CAR T cells. Primary endpoints were safety and maximum tolerated dose (MTD); secondary endpoints included overall response rate (ORR), progression-free survival (PFS), and overall survival (OS). Data cutoff was 23August2024. Cytokine release syndrome (CRS) occurred in 82% of patients, immune effector cell-associated neurotoxicity syndrome in 10%, and other select neurotoxicities in 12%; most were grade 1/2 and frequency appeared dose-dependent. One death occurred from CRS at highest dose level. On-target/off-tumor skin (30%), nail (19%), and oral (32%) adverse events were transient, grade 1/2; most resolved without intervention. MTD was not reached. With median follow-up of 16.1 months, ORR=87% (complete response rate=53%), median duration of response=18.0 months, and median PFS=18.3 months (95% CI, 11.8-21.9) (n=79). The 1-year OS rate was 90% (N=84). In conclusion, arlo-cel had a safety profile supportive of future study and demonstrated deep and durable responses, with promising PFS and OS in patients with heavily pretreated RRMM.
Lossa J, Schnöder TM, Ronge Z
… +20 more, Haasch N, Hodapp K, Marini F, Abassi N, Gaida MM, Lee SJ, Henrich A, Höhne-Wiechmann MN, Thull Mogollón C, Schütze K, Klein M, Bopp T, Schild H, Sasca D, Crodel CC, Heidel FH, Koschmieder S, Probst HC, Radsak MP, Muth S
Polycythemia vera (PV) is a clonal hematopoietic stem cell (HSC) disorder resulting in overproduction of erythrocytes. While Interferon-a (IFN-a) has shown therapeutic efficacy in PV and other myeloproliferative neoplasm...Polycythemia vera (PV) is a clonal hematopoietic stem cell (HSC) disorder resulting in overproduction of erythrocytes. While Interferon-a (IFN-a) has shown therapeutic efficacy in PV and other myeloproliferative neoplasms (MPN), its precise mechanism of action remains poorly understood. In this study, we identify natural killer (NK) cells as primary immune effectors responsive to IFN-a treatment in PV essential for disease control in vivo. Using a transgenic mouse model of PV, we demonstrate that IFN-a induces the expansion of CD27+ NK cells in the bone marrow. In patients with PV or ET undergoing IFN-a therapy, the frequency of CD56bright NK cells is increased and correlates with the molecular response. Depletion of NK cells abrogated the therapeutic effects of IFN-a. In vitro experiments demonstrate that NK cells preferentially killed Jak2VF mutant hematopoietic stem and progenitor cells (HSPCs) in a TNF-a dependent manner and independent of IFN-g or NKG2D. Notably, PV mice depleted of NK cells or lacking type-I interferon (IFN) receptor on NK cells showed accelerated disease progression in the absence of exogenous IFN-a. This suggests that direct sensing of basal levels of type-I IFNs by NK cells is essential for attenuating disease progression, emphasizing a critical role for NK cells in immune surveillance of MPN. These findings offer new insights into type-I IFN-mediated immune modulation in MPN and highlight the potential of NK cell activation to improve therapeutic outcomes.
Juvenile myelomonocytic leukemia (JMML) is an aggressive pediatric myelodysplastic syndrome or myeloproliferative disorder for which hematopoietic stem cell transplantation remains the only curative option; however, outc...Juvenile myelomonocytic leukemia (JMML) is an aggressive pediatric myelodysplastic syndrome or myeloproliferative disorder for which hematopoietic stem cell transplantation remains the only curative option; however, outcomes are particularly poor in patients harboring PTPN11 (encodes SHP2 phosphatase) mutations. Using a Shp2E76K/+ JMML mouse model, we identify a pathogenic IL-17A/PTGS2/NLRP3 signaling axis that drives bone marrow inflammation, suppresses antitumor immunity, and promotes leukemic progression. Shp2E76K/+ mice exhibited profound immune dysregulation, characterized by expansion of regulatory T cells (Tregs), increased T-cell exhaustion, and impaired cytotoxic function with reduced CD4⁺ and CD8⁺ T-cell frequencies. Mechanistically, mutant macrophages upregulated IL-17A, triggering NLRP3 inflammasome activation, PTGS2 induction, caspase-1 cleavage, and IL-1β maturation, thereby amplifying inflammatory signaling within the marrow niche. Therapeutically, IL-17A neutralization suppressed inflammasome activity, while combined inhibition of NLRP3 and PTGS2 restored cytotoxic T-cell function, reduced systemic and marrow inflammation, reversed myeloproliferation, and significantly prolonged survival in Shp2E76K/+ mice. Importantly, ex vivo treatment of primary JMML patient samples with dual NLRP3/PTGS2 inhibition combined with MEK blockade significantly reduced leukemic progenitor colony formation, supporting translational relevance. In patient-derived xenograft models of PTPN11-mutant JMML, dual NLRP3/PTGS2 inhibition combined with MEK blockade most effectively reduced leukemic burden, decreased human CD45⁺ engraftment, and depleted leukemic CD34⁺CD38⁺ progenitors and GMPs while restoring MEP populations, resulting in significantly improved overall survival. Together, these findings establish IL-17A/PTGS2/NLRP3 signaling as a central driver of immune suppression and myeloid expansion in PTPN11-mutant JMML and highlight combinatorial anti-inflammatory targeting as a promising therapeutic strategy for this high-risk disease.
Non-myeloablative-related haploidentical allogeneic stem cell transplantation (NMAC-HID allo-HSCT) emerged as an additional treatment for achieving durable remission in SCD, a prevalent blood disorder characterized by pa...Non-myeloablative-related haploidentical allogeneic stem cell transplantation (NMAC-HID allo-HSCT) emerged as an additional treatment for achieving durable remission in SCD, a prevalent blood disorder characterized by painful vaso-occlusive crises and chronic anemia. The standard-of-care (SOC) for SCD includes hydroxyurea, pain management, and blood transfusion, but patients with SCD still lose several decades of life expectancy. Gene therapy (GT) for SCD is the other treatment for lifelong disease amelioration in SCD, with accessibility limited by cost and manufacturing capacity in the US and globally. Two recent prospective studies evaluating NMAC-HID allo-HSCT validated haploidentical allotransplantation as an efficacious and accessible treatment option in the era of gene therapy. Given ongoing price negotiation across jurisdictions for GT implementation and the absence of cost-effectiveness data comparing NMAC-HID allo-HSCT versus GT, we conducted a cost-effectiveness analysis of NMAC-HID allo-HST versus GT versus SOC for adults and children living with SCD. The primary outcomes were the incremental cost-effectiveness ratio and the net monetary benefits (NMBs) across these three strategies. The secondary outcome was the maximum cost-effective threshold price for GT compared to NMAC-HID allo-HSCT. Treatment with SOC, NMAC-HID allo-HSCT, and GT accrued 14.3, 20.1, and 22.1 QALYs at costs of $1.22 million, $1.15 million and $2.75 million respectively. NMAC-HID allo-HSCT was the cost-effective strategy versus GT in 100% of 10,000 Monte Carlo iterations across the base-case and all scenario analyses. The maximum cost-effective thresholds for GT vs SOC were $1.4 million in the United States and $4,200-$22,000 across India, Nigeria, and Tanzania, depending on willingness-to-pay.
Wang ES, Erba HP, Zeidan AM
… +33 more, Roboz GJ, Altman JK, Advani AS, Lin TL, Strickland SA, Juckett MB, Pratz KW, Mangan JK, McMahon CM, Alsfeld LC, Balasubramanian SK, Guru Murthy GS, Rotta M, Palmisiano N, McCloskey J, Saliba AN, Khawandanah M, Madanat YF, Naqvi K, Qasrawi AH, Schiller GJ, Badar T, Gojo I, Yaghmour G, Osman D, Zhang H, Tian Y, Soifer HS, Riches M, Corum D, Leoni M, Fathi AT, Issa GC
Ziftomenib - a potent, selective, oral menin inhibitor - is approved as monotherapy for adults with relapsed/refractory (R/R) NPM1-mutated acute myeloid leukemia (NPM1-m AML). The KOMET-007 phase 1 trial investigated cli...Ziftomenib - a potent, selective, oral menin inhibitor - is approved as monotherapy for adults with relapsed/refractory (R/R) NPM1-mutated acute myeloid leukemia (NPM1-m AML). The KOMET-007 phase 1 trial investigated clinical activity and tolerability of ziftomenib in combination with standard therapies for R/R and newly diagnosed AML. Here, we report outcomes of adults with R/R NPM1-m AML treated with ziftomenib plus venetoclax/azacitidine. In phase 1a, patients received ziftomenib 200, 400, or 600 mg once daily with standard doses of venetoclax/azacitidine. In phase 1b, ziftomenib 600 mg was selected for expansion. Sixty-seven patients were treated (27 phase 1a; 40 phase 1b). Median age was 66 years, and 55% were men. Median number of prior therapies was 1 (range 1-8); 55% received prior venetoclax and 22% had prior transplantation. Most common (≥20%) grade ≥3 treatment-emergent adverse events were leukopenia (34%), thrombocytopenia (28%), febrile neutropenia and neutropenia (25% each). Six patients developed QTc prolongation (1 ziftomenib-related; grade 1), and 2 experienced differentiation syndrome (grade 3); all events were successfully managed. In patients receiving ziftomenib 600 mg, composite complete remission (CRc) rate was 46% (22/48), with 67% (12/18) achieving central measurable residual disease (MRD) negativity (<0.01% threshold). In venetoclax-naïve and -exposed patients, CRc rates were 70% (16/23) and 24% (6/25), with MRD-negativity rates of 75% (9/12) and 50% (3/6), respectively. Median duration of response was 8.6 months, and median overall survival was not reached. The combination of ziftomenib 600 mg with venetoclax/azacitidine was well tolerated with deep and durable clinical activity in R/R NPM1-m AML. This trial was registered at www.ClinicalTrials.gov as #NCT05735184.
Kennedy VE, Peretz CAC, Walia A
… +31 more, Chyla B, Sun Y, Hill JE, Tran E, Koh AD, Ferng TT, Pintar S, Jones M, Popescu B, Lomeli I, Chehab F, Murad N, John A, Roy RP, Olshen AB, Berryhill CA, Davis C, Angus SP, Rivera JM, Meshulam A, Stieglitz E, Joshi SK, Traer E, Dail M, Hamidi H, Altman JK, Daver NG, Levis MJ, McCloskey J, Perl AE, Smith CC
Bulk sequencing of relapsed tumors reveals mutations associated with resistance to cancer therapy but is insufficient to fully assess all causes of relapse. Due to inherent tumor heterogeneity, on-treatment tumor evoluti...Bulk sequencing of relapsed tumors reveals mutations associated with resistance to cancer therapy but is insufficient to fully assess all causes of relapse. Due to inherent tumor heterogeneity, on-treatment tumor evolution may select for genetically distinct clones or shifts in malignant transcriptional states not resolvable by bulk sequencing. We performed multiomic single cell (SC) DNA/protein and RNA/protein profiling of a clinical trial cohort of acute myeloid leukemia (AML) patients treated on the Phase 1b clinical trial of the BCL2 inhibitor venetoclax and the FLT3 inhibitor gilteritinib (Ven/Gilt) to characterize immunophenotypic, transcriptional, and genetic clonal evolution driving resistance. We found that while Ven/Gilt effectively eliminated FLT3 mutant clones, resistance was associated with RAS activation via multiple mechanisms including selection for RAS mutant clones, non-mutational upregulation of RAS transcriptional programs and a shift to RAS-associated monocytic AML differentiation. In an in vitro model of monocytic differentiation associated with non-mutational RAS transcriptional activation, we demonstrated that RAS pathway inhibition re-sensitized to Ven/Gilt. These data illustrate that convergent resistance pathways in patients can be activated via diverse genetic and non-genetic mechanisms. These results underscore that RAS signaling is central to FLT3 and BCL2 inhibitor resistance, is tightly coupled to AML monocytic differentiation and highlight RAS pathway inhibition as a viable clinical strategy to combat resistance. CT# NCT03625505.