Exportin 1 governs the immunosuppressive functions of myeloid-derived suppressor cells in tumors through ERK1/2 nuclear export.

Myeloid-derived suppressor cells (MDSCs) are a main driver of immunosuppression in tumors. Understanding the mechanisms that determine the development and immunosuppressive function of these cells could provide new therapeutic targets to improve antitumor immunity. Here, using preclinical murine models, we discovered that exportin 1 (XPO1) expression is upregulated in tumor MDSCs and that this upregulation is induced by IL-6-induced STAT3 activation during MDSC differentiation.

Outcomes of Human Leukocyte Antigen-Matched Related Donor and Haploidentical Allogeneic Hematopoietic Cell Transplantation Recipients by Immune Profiles of Recipients and Donors.

Haploidentical (Haplo) allogeneic HCTs (alloHCT) have been used more frequently over the last decade as survival is similar to HLA-matched related donor (MRD) alloHCTs. We aimed to identify donor and recipient immune signatures before alloHCT that are associated with clinically meaningful outcomes in MRD vs Haplo alloHCT recipients. This retrospective cohort study of 165 MRD (n = 132) and Haplo (n = 33) alloHCT recipients and their related donors between 2007-2019 with paired peripheral blood samples immunophenotyped for T-cell, B-cell, NK cell and dendritic cell (DC) subsets.

Minimal Residual Disease Status in Multiple Myeloma 1 Year After Autologous Hematopoietic Cell Transplantation and Lenalidomide Maintenance Are Associated With Long-Term Overall Survival.

Purpose: Prognostic Immunophenotyping in Myeloma Response (PRIMeR) is an ancillary study of minimal residual disease (MRD) assessment for multiple myeloma by next-generation multiparameter flow cytometry (MFC). Patients were enrolled on a three-arm randomized control trial (Blood and Marrow Transplants Clinical Trials Network 0702 Stem Cell Transplant for Myeloma in Combination of Novel Agents [STaMINA]; ClinicalTrials.gov identifier: NCT01109004).

Myeloid-derived suppressor cell mitochondrial fitness governs chemotherapeutic efficacy in hematologic malignancies.

Myeloid derived suppressor cells (MDSCs) are key regulators of immune responses and correlate with poor outcomes in hematologic malignancies. Here, we identify that MDSC mitochondrial fitness controls the efficacy of doxorubicin chemotherapy in a preclinical lymphoma model. Mechanistically, we show that triggering STAT3 signaling via β2-adrenergic receptor (β2-AR) activation leads to improved MDSC function through metabolic reprograming, marked by sustained mitochondrial respiration and higher ATP generation which reduces AMPK signaling, altering energy metabolism.

Associations of minor histocompatibility antigens with outcomes following allogeneic hematopoietic cell transplantation.

The role of minor histocompatibility antigens (mHAs) in mediating graft versus leukemia and graft versus host disease (GvHD) following allogeneic hematopoietic cell transplantation (alloHCT) is recognized but not well-characterized. By implementing improved methods for mHA prediction in two large patient cohorts, this study aimed to comprehensively explore the role of mHAs in alloHCT by analyzing whether (1) the number of predicted mHAs, or (2) individual mHAs are associated with clinical outcomes. The study population consisted of 2249 donor-recipient pairs treated for acute myeloid leukemia and myelodysplastic syndrome with alloHCT.

Galectin-3 expression in donor T cells reduces GvHD severity and lethality after allogeneic hematopoietic cell transplantation.

Abundant donor cytotoxic T cells that attack normal host organs remain a major problem for patients receiving allogeneic hematopoietic cell transplantation (allo-HCT). Despite an increase in our knowledge of the pathobiology of acute graft versus host disease (aGvHD), the mechanisms regulating the proliferation and function of donor T cells remain unclear. Here, we show that activated donor T cells express galectin-3 (Gal-3) after allo-HCT.

Shared graft-versus-leukemia minor histocompatibility antigens in DISCOVeRY-BMT.

T-cell responses to minor histocompatibility antigens (mHAs) mediate graft-versus-leukemia (GVL) effects and graft-versus-host disease (GVHD) in allogeneic hematopoietic cell transplantation. Therapies that boost T-cell responses improve allogeneic hematopoietic cell transplant (alloHCT) efficacy but are limited by concurrent increases in the incidence and severity of GVHD. mHAs with expression restricted to hematopoietic tissue (GVL mHAs) are attractive targets for driving GVL without causing GVHD.

Short-Term Storage of Mobilized Peripheral Blood Stem Cells in a Closed System Changes the Microenvironment and May Affect the Quantity of CD34 and CD34CD38CD45RACD90 Cells.

Hypoxic conditions preserve the multipotency and self-renewing capacity of murine bone marrow and human cord blood stem cells. Blood samples stored in sealed blood gas tubes become hypoxic as leukocytes metabolize and consume oxygen. Taken together, these observations suggest that peripheral blood stem cell (PBSC) samples stored under airtight conditions become hypoxic, and that the stem cells contained may undergo qualitative or quantitative changes.

Spatiotemporal assessment of immunogenomic heterogeneity in multiple myeloma.

Spatial heterogeneity is a common phenomenon in metastatic solid tumors and an evolving concept in multiple myeloma (MM). The interplay between malignant plasma cells (PCs) and the microenvironment has not yet been analyzed in MM. For this purpose, we performed bone marrow aspirates and imaging-guided biopsies of corresponding lesions in newly diagnosed MM (NDMM) and relapsed/refractory MM (RRMM) patients.

Whole-body magnetic resonance imaging plus serological follow-up for early identification of progression in smouldering myeloma patients to prevent development of end-organ damage.

The definition of multiple myeloma (MM) was updated in 2014, with the intent to enable earlier treatment and thereby avoid appearance of end-organ damage at progression from smouldering multiple myeloma (SMM) to MM. The purpose of this study was to investigate to which extent the development of end-organ damage at progression to MM was reduced under the updated guidelines. In this prospective observational cohort study (ClinicalTrials.

Proceedings from the Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Immune and Cellular Therapy in Multiple Myeloma.

The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup conducted a workshop on Immune and Cellular Therapy in Multiple Myeloma on January 7, 2022. This workshop included presentations by basic, translational, and clinical researchers with expertise in plasma cell dyscrasias. Four main topics were discussed: platforms for myeloma disease evaluation, insights into pathophysiology, therapeutic target and resistance mechanisms, and cellular therapy for multiple myeloma.

A review of the current status of lenalidomide maintenance therapy in multiple myeloma in 2022.

Introduction: Recent advances in the diagnosis and management of multiple myeloma (MM) have improved patient outcomes. This progress in our understanding of MM has resulted in continuous suppressive therapy concepts, including induction, high dose chemotherapy with autologous stem cell transplantation (ASCT), consolidation, and maintenance therapy. The foundation of maintenance therapy has been with lenalidomide.

Novel genetic variants associated with mortality after unrelated donor allogeneic hematopoietic cell transplantation.

Background: Identification of non-human leukocyte antigen (HLA) genetic risk factors could improve survival after allogeneic blood or marrow transplant (BMT) through matching at additional loci or individualizing risk prediction. We hypothesized that non-HLA loci contributed significantly to 1-year overall survival (OS), disease related mortality (DRM) or transplant related mortality (TRM) after unrelated donor (URD)BMT.

Methods: We performed a genome-wide association study (GWAS) in 2,887 acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) and acute lymphoblastic leukemia (ALL) patients and their ≥8/8 HLA-matched URDs comprising two independent cohorts treated from 2000-2011.

Serological Response to Vaccination after Autologous Transplantation for Multiple Myeloma Is Associated with Improved Progression-Free and Overall Survival.

Revaccination after autologous hematopoietic cell transplantation (AHCT) is recommended in post-HCT survivorship guidelines to restore humoral immunity. Data on seroconversion after AHCT and vaccination in multiple myeloma (MM) patients are limited. We investigated the feasibility and effectiveness of vaccination post-AHCT and analyzed the restoration of humoral immunity and patient prognosis.

β2-adrenergic receptor signaling regulates metabolic pathways critical to myeloid-derived suppressor cell function within the TME.

Myeloid-derived suppressor cells (MDSCs) impede antitumor immunity; however, the precise mechanisms that regulate their suppressive function remain unresolved. Identifying these mechanisms could lead to therapeutic interventions to boost cancer immunotherapy efficacy. Here, we reveal that β2 adrenergic receptor (β2-AR) expression on MDSCs increases with tumor growth and that the β2-AR stress pathway drives the immune suppressive activity of MDSCs by altering their metabolism.

A phase I/II study of ixazomib, pomalidomide, and dexamethasone for lenalidomide and proteasome inhibitor refractory multiple myeloma (Alliance A061202).

Preclinical studies have demonstrated activity of the oral proteasome inhibitor (PI) ixazomib (IXA) in bortezomib-resistant multiple myeloma (MM) and synergy with immunomodulatory drugs. We therefore conducted a phase I/II study to establish the safety and preliminary efficacy of IXA with pomalidomide (POM) and dexamethasone (DEX) in lenalidomide (LEN)/PI-refractory MM. Dose escalation established a 4 mg dose of POM and IXA and 20/40 mg dose of DEX as the maximum tolerated dose.

Replicated Risk Index of Patient Functional Status Prior to Allogeneic Hematopoietic Cell Transplantation Predicts Healthcare Utilization and Survival.

Poor physical functioning is associated with adverse outcomes after allogeneic hematopoietic cell transplantation (alloHCT). Analytic tools to predict mortality in alloHCT recipients include the HCT Comorbidity Index (HCT-CI) based on comorbidities and the Disease Risk Index (DRI) based on disease and disease status. We developed and replicated a risk model for overall survival (OS), early mortality (ie, death from any cause at or before day +100), initial hospital length of stay (LOS), and percentage of inpatient days within the first year post-alloHCT.

The 2020 BMT CTN Myeloma Intergroup Workshop on Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma.

The fifth annual Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma was conducted as one of the American Society of Hematology Annual Meeting Scientific Workshops on Thursday December 3, 2020. This workshop focused on four main topics: (1) integrating minimal residual disease into clinical trial design and practice; (2) the molecular and immunobiology of disease evolution and progression in myeloma; (3) adaptation of next-generation sequencing, next-generation flow cytometry, and cytometry by time of flight techniques; and (4) chimeric antigen receptor T-cell and other cellular therapies for myeloma. In this report, we provide a summary of the workshop presentations and discuss future directions in the field.

Future Directions in Maintenance Therapy in Multiple Myeloma.

Autologous stem cell transplantation (ASCT) has been a backbone of therapy for newly diagnosed patients with multiple myeloma eligible for high-dose therapy for decades. Survival outcomes have continued to improve over time, in part because of the incorporation of highly effective induction regimens prior to ASCT as well as post-ASCT maintenance therapy. Randomized phase III clinical trials have helped establish lenalidomide maintenance as a standard of care.

Optical Coherence Tomography for Quantifying Human Cutaneous Chronic Graft-versus-Host Disease.

Chronic graft-versus-host disease (cGVHD) is the most common cause of nonrelapse mortality after allogeneic hematopoietic cell transplantation (alloHCT). Cutaneous cGVHD is characterized by thickening of the skin and connective tissues, causing discomfort and limited mobility. Current assessment of these skin lesions is based on physical examination of their thickening, pinchability, and movability.

Pre-HCT mosaicism increases relapse risk and lowers survival in acute lymphoblastic leukemia patients post-unrelated HCT.

Pre-HCT mosaicism is related to increased relapse risk and lower survival after unrelated HCT, independent of cytogenetics at diagnosis. Pre-HCT mosaicism could be a useful clinical tool to guide risk stratification in acute lymphoblastic leukemia patients.