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Nature Cancer May 2023Multiple myeloma (MM) is a plasma cell malignancy defined by complex genetics and extensive patient heterogeneity. Despite a growing arsenal of approved therapies, MM...
Multiple myeloma (MM) is a plasma cell malignancy defined by complex genetics and extensive patient heterogeneity. Despite a growing arsenal of approved therapies, MM remains incurable and in need of guidelines to identify effective personalized treatments. Here, we survey the ex vivo drug and immunotherapy sensitivities across 101 bone marrow samples from 70 patients with MM using multiplexed immunofluorescence, automated microscopy and deep-learning-based single-cell phenotyping. Combined with sample-matched genetics, proteotyping and cytokine profiling, we map the molecular regulatory network of drug sensitivity, implicating the DNA repair pathway and EYA3 expression in proteasome inhibitor sensitivity and major histocompatibility complex class II expression in the response to elotuzumab. Globally, ex vivo drug sensitivity associated with bone marrow microenvironmental signatures reflecting treatment stage, clonality and inflammation. Furthermore, ex vivo drug sensitivity significantly stratified clinical treatment responses, including to immunotherapy. Taken together, our study provides molecular and actionable insights into diverse treatment strategies for patients with MM.
Topics: Humans; Multiple Myeloma; Plasma Cells; Proteasome Inhibitors; Bone Marrow; Immunotherapy
PubMed: 37081258
DOI: 10.1038/s43018-023-00544-9 -
The Journal of Cell Biology Jun 2024Cells exposed to proteotoxic stress invoke adaptive responses aimed at restoring proteostasis. Our previous studies have established a firm role for the transcription...
Cells exposed to proteotoxic stress invoke adaptive responses aimed at restoring proteostasis. Our previous studies have established a firm role for the transcription factor Nuclear factor-erythroid derived-2-related factor-1 (Nrf1) in responding to proteotoxic stress elicited by inhibition of cellular proteasome. Following proteasome inhibition, Nrf1 mediates new proteasome synthesis, thus enabling the cells to mitigate the proteotoxic stress. Here, we report that under similar circumstances, multiple components of the autophagy-lysosomal pathway (ALP) were transcriptionally upregulated in an Nrf1-dependent fashion, thus providing the cells with an additional route to cope with proteasome insufficiency. In response to proteasome inhibitors, Nrf1-deficient cells displayed profound defects in invoking autophagy and clearance of aggresomes. This phenomenon was also recapitulated in NGLY1 knockout cells, where Nrf1 is known to be non-functional. Conversely, overexpression of Nrf1 induced ALP genes and endowed the cells with an increased capacity to clear aggresomes. Overall, our results significantly expand the role of Nrf1 in shaping the cellular response to proteotoxic stress.
Topics: Animals; Humans; Mice; Autophagy; Lysosomes; NF-E2-Related Factor 1; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Proteostasis; Proteotoxic Stress; Stress, Physiological
PubMed: 38656405
DOI: 10.1083/jcb.202306150 -
Frontiers in Immunology 2022Multiple myeloma is an incurable cancer of plasma cells that is predominantly located in the bone marrow. Multiple myeloma cells are characterized by distinctive... (Review)
Review
Multiple myeloma is an incurable cancer of plasma cells that is predominantly located in the bone marrow. Multiple myeloma cells are characterized by distinctive biological features that are intricately linked to their core function, the assembly and secretion of large amounts of antibodies, and their diverse interactions with the bone marrow microenvironment. Here, we provide a concise and introductory discussion of major metabolic hallmarks of plasma cells and myeloma cells, their roles in myeloma development and progression, and how they could be exploited for therapeutic purposes. We review the role of glucose consumption and catabolism, assess the dependency on glutamine to support key metabolic processes, and consider metabolic adaptations in drug-resistant myeloma cells. Finally, we examine the complex metabolic effects of proteasome inhibitors on myeloma cells and the extracellular matrix, and we explore the complex relationship between myeloma cells and bone marrow adipocytes.
Topics: Bone Marrow; Humans; Multiple Myeloma; Proteasome Inhibitors; Tumor Microenvironment
PubMed: 36072593
DOI: 10.3389/fimmu.2022.897862 -
International Journal of Molecular... Feb 2023Over the past 40 years, the 5-years-overall survival rate of pediatric cancer reached 75-80%, and for acute lymphoblastic leukemia (ALL), exceeded 90%. Leukemia... (Review)
Review
Over the past 40 years, the 5-years-overall survival rate of pediatric cancer reached 75-80%, and for acute lymphoblastic leukemia (ALL), exceeded 90%. Leukemia continues to be a major cause of mortality and morbidity for specific patient populations, including infants, adolescents, and patients with high-risk genetic abnormalities. The future of leukemia treatment needs to count better on molecular therapies as well as immune and cellular therapy. Advances in the scientific interface have led naturally to advances in the treatment of childhood cancer. These discoveries have involved the recognition of the importance of chromosomal abnormalities, the amplification of the oncogenes, the aberration of tumor suppressor genes, as well as the dysregulation of cellular signaling and cell cycle control. Lately, novel therapies that have already proven efficient on relapsed/refractory ALL in adults are being evaluated in clinical trials for young patients. Tirosine kinase inhibitors are, by now, part of the standardized treatment of Ph+ALL pediatric patients, and Blinatumomab, with promising results in clinical trials, received both FDA and EMA approval for use in children. Moreover, other targeted therapies such as aurora-kinase inhibitors, MEK-inhibitors, and proteasome-inhibitors are involved in clinical trials that include pediatric patients. This is an overview of the novel leukemia therapies that have been developed starting from the molecular discoveries and those that have been applied in pediatric populations.
Topics: Adolescent; Adult; Child; Humans; Antibodies, Bispecific; Immunotherapy; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proteasome Inhibitors
PubMed: 36902091
DOI: 10.3390/ijms24054661 -
Acta Haematologica 2020The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and... (Review)
Review
The gut microbiota plays a significant role in health and disease, including cancer development and treatment. The importance of the gut microbiota in the efficacy and toxicity of novel therapies and immunotherapy is increasingly recognized. Plasma cells in multiple myeloma have the potential to survive in the gastrointestinal tract for long periods of time. The nature of the gut microbiota impacts the degree of antigen stimulation of these cells and may play a role in mutation development and clonal evolution. Furthermore, myeloma therapies such as proteasome inhibitors and alkylating agents, commonly used to treat patients, are frequently associated with gastrointestinal adverse events. Herein we review the gut microbiota and its role in hematopoiesis, pathogenesis of myeloma, and efficacy/toxicity of anti-myeloma therapies.
Topics: Antineoplastic Agents, Alkylating; Cytokines; Gastrointestinal Microbiome; Humans; Multiple Myeloma; NF-kappa B; Plasma Cells; Proteasome Inhibitors; Signal Transduction
PubMed: 31311009
DOI: 10.1159/000500976 -
American Journal of Transplantation :... Jun 2020Plasma cells (PCs) are the major source of pathogenic allo- and autoantibodies and have historically demonstrated resistance to therapeutic targeting. However,... (Review)
Review
Plasma cells (PCs) are the major source of pathogenic allo- and autoantibodies and have historically demonstrated resistance to therapeutic targeting. However, significant recent clinical progress has been made with the use of second-generation proteasome inhibitors (PIs). PIs provide efficient elimination of plasmablast-mediated humoral responses; however, long-lived bone marrow (BM) resident PCs (LLPCs) demonstrate therapeutic resistance, particularly to first-generation PIs. In addition, durability of antibody (Ab) reduction still requires improvement. More recent clinical trials have focused on conditions mediated by LLPCs and have included mechanistic studies of LLPCs from PI-treated patients. A recent clinical trial of carfilzomib (a second-generation irreversible PI) demonstrated improved efficacy in eliminating BM PCs and reducing anti-HLA Abs in chronically HLA-sensitized patients; however, Ab rebound was observed over several weeks to months following PI therapy. Importantly, recent murine studies have provided substantial insights into PC biology, thereby further enhancing our understanding of PC populations. It is now clear that BMPC populations, where LLPCs are thought to primarily reside, are heterogeneous and have distinct gene expression, metabolic, and survival signatures that enable identification and characterization of PC subsets. This review highlights recent advances in PC biology and clinical trials in transplant populations.
Topics: Animals; Autoantibodies; Humans; Mice; Plasma Cells; Proteasome Inhibitors
PubMed: 32538532
DOI: 10.1111/ajt.15889 -
Neoplasia (New York, N.Y.) Jan 2022The introduction of the proteasome inhibitor bortezomib into treatment regimens for myeloma has led to substantial improvement in patient survival. However, whilst...
The introduction of the proteasome inhibitor bortezomib into treatment regimens for myeloma has led to substantial improvement in patient survival. However, whilst bortezomib elicits initial responses in many myeloma patients, this haematological malignancy remains incurable due to the development of acquired bortezomib resistance. With other patients presenting with disease that is intrinsically bortezomib resistant, it is clear that new therapeutic approaches are desperately required to target bortezomib-resistant myeloma. We have previously shown that targeting sphingolipid metabolism with the sphingosine kinase 2 (SK2) inhibitor K145 in combination with bortezomib induces synergistic death of bortezomib-naïve myeloma. In the current study, we have demonstrated that targeting sphingolipid metabolism with K145 synergises with bortezomib and effectively resensitises bortezomib-resistant myeloma to this proteasome inhibitor. Notably, these effects were dependent on enhanced activation of the unfolded protein response, and were observed in numerous separate myeloma models that appear to have different mechanisms of bortezomib resistance, including a new bortezomib-resistant myeloma model we describe which possesses a clinically relevant proteasome mutation. Furthermore, K145 also displayed synergy with the next-generation proteasome inhibitor carfilzomib in bortezomib-resistant and carfilzomib-resistant myeloma cells. Together, these findings indicate that targeting sphingolipid metabolism via SK2 inhibition may be effective in combination with a broad spectrum of proteasome inhibitors in the proteasome inhibitor resistant setting, and is an approach worth clinical exploration.
Topics: Animals; Antineoplastic Agents; Bortezomib; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Enzyme Inhibitors; Gene Knockout Techniques; Humans; Mice; Multiple Myeloma; Phosphotransferases (Alcohol Group Acceptor); Proteasome Inhibitors; Structure-Activity Relationship; Unfolded Protein Response; Xenograft Model Antitumor Assays
PubMed: 34826777
DOI: 10.1016/j.neo.2021.11.009 -
Molecular Oncology Sep 2023In previous studies, we demonstrated that panobinostat, a histone deacetylase inhibitor, and bortezomib, a proteasomal inhibitor, displayed synergistic therapeutic...
In previous studies, we demonstrated that panobinostat, a histone deacetylase inhibitor, and bortezomib, a proteasomal inhibitor, displayed synergistic therapeutic activity against pediatric and adult high-grade gliomas. Despite the remarkable initial response to this combination, resistance emerged. Here, in this study, we aimed to investigate the molecular mechanisms underlying the anticancer effects of panobinostat and marizomib, a brain-penetrant proteasomal inhibitor, and the potential for exploitable vulnerabilities associated with acquired resistance. RNA sequencing followed by gene set enrichment analysis (GSEA) was employed to compare the molecular signatures enriched in resistant compared with drug-naïve cells. The levels of adenosine 5'-triphosphate (ATP), nicotinamide adenine dinucleotide (NAD) content, hexokinase activity, and tricarboxylic acid (TCA) cycle metabolites required for oxidative phosphorylation to meet their bioenergetic needs were analyzed. Here, we report that panobinostat and marizomib significantly depleted ATP and NAD content, increased mitochondrial permeability and reactive oxygen species generation, and promoted apoptosis in pediatric and adult glioma cell lines at initial treatment. However, resistant cells exhibited increased levels of TCA cycle metabolites, which required for oxidative phosphorylation to meet their bioenergetic needs. Therefore, we targeted glycolysis and the electron transport chain (ETC) with small molecule inhibitors, which displayed substantial efficacy, suggesting that resistant cell survival is dependent on glycolytic and ETC complexes. To verify these observations in vivo, lonidamine, an inhibitor of glycolysis and mitochondrial function, was chosen. We produced two diffuse intrinsic pontine glioma (DIPG) models, and lonidamine treatment significantly increased median survival in both models, with particularly dramatic effects in panobinostat- and marizomib-resistant cells. These data provide new insights into mechanisms of treatment resistance in gliomas.
Topics: Humans; Adult; Child; Panobinostat; NAD; Glioma; Proteasome Inhibitors; Mitochondria; Cell Line, Tumor
PubMed: 37014128
DOI: 10.1002/1878-0261.13427 -
Pediatric Blood & Cancer Oct 2021Ubiquitin proteasome-mediated protein degradation has been implicated in posttranslational oncogenesis in medulloblastoma. Current research is evaluating the clinical... (Review)
Review
Ubiquitin proteasome-mediated protein degradation has been implicated in posttranslational oncogenesis in medulloblastoma. Current research is evaluating the clinical implications of proteasome inhibition as a therapeutic target. In medulloblastoma cell lines, proteasome inhibitors induce apoptosis and inhibit cell proliferation via multiple pathways involving activation of caspase pathways, NFκB (nuclear factor kappa-light-chain-enhancer of activated B cells) pathway inhibition, reduced AKT/mTOR pathway activity, and pro-apoptotic protein expression. Second-generation proteasome inhibitors demonstrate blood-brain barrier penetration while maintaining antitumor effect. This review summarizes the ubiquitin-proteasome system in the pathogenesis of medulloblastoma and the potential clinical implications.
Topics: Apoptosis; Cerebellar Neoplasms; Humans; Medulloblastoma; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Ubiquitin
PubMed: 34114315
DOI: 10.1002/pbc.29168 -
Frontiers in Cellular and Infection... 2021Ubiquitin-proteasome mediated protein turnover is an important regulatory mechanism of cellular function in eukaryotes. Extensive studies have linked the... (Review)
Review
Ubiquitin-proteasome mediated protein turnover is an important regulatory mechanism of cellular function in eukaryotes. Extensive studies have linked the ubiquitin-proteasome system (UPS) to human diseases, and an array of proteasome inhibitors have been successfully developed for cancer therapy. Although still an emerging field, research on UPS regulation of fungal development and virulence has been rapidly advancing and has generated considerable excitement in its potential as a target for novel drugs. In this review, we summarize UPS composition and regulatory function in pathogenic fungi, especially in stress responses, host adaption, and fungal pathogenesis. Emphasis will be given to UPS regulation of pathogenic factors that are important for fungal pathogenesis. We also discuss future potential therapeutic strategies for fungal infections based on targeting UPS pathways.
Topics: Fungi; Humans; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Proteolysis; Ubiquitin
PubMed: 34858882
DOI: 10.3389/fcimb.2021.774613