RESUMO
Palatine tonsils are secondary lymphoid organs (SLOs) representing the first line of immunological defense against inhaled or ingested pathogens. We generated an atlas of the human tonsil composed of >556,000 cells profiled across five different data modalities, including single-cell transcriptome, epigenome, proteome, and immune repertoire sequencing, as well as spatial transcriptomics. This census identified 121 cell types and states, defined developmental trajectories, and enabled an understanding of the functional units of the tonsil. Exemplarily, we stratified myeloid slan-like subtypes, established a BCL6 enhancer as locally active in follicle-associated T and B cells, and identified SIX5 as putative transcriptional regulator of plasma cell maturation. Analyses of a validation cohort confirmed the presence, annotation, and markers of tonsillar cell types and provided evidence of age-related compositional shifts. We demonstrate the value of this resource by annotating cells from B cell-derived mantle cell lymphomas, linking transcriptional heterogeneity to normal B cell differentiation states of the human tonsil.
Assuntos
Linfócitos B , Tonsila Palatina , Humanos , Adulto , Linfócitos B/metabolismoRESUMO
ABSTRACT: Plasma cells (PCs) are highly specialized cells representing the end stage of B-cell differentiation. We have shown that PC differentiation can be reproduced in vitro using elaborate culture systems. The molecular changes occurring during PC differentiation are recapitulated in this in vitro differentiation model. However, a major challenge exists to decipher the spatiotemporal epigenetic and transcriptional programs that drive the early stages of PC differentiation. We combined single cell (sc) RNA sequencing (RNA-seq) and assay for transposase-accessible chromatin with high throughput sequencing (scATAC-seq) to decipher the trajectories involved in PC differentiation. ScRNA-seq experiments revealed a strong heterogeneity of the preplasmablastic and plasmablastic stages. Among genes that were commonly identified using scATAC-seq and scRNA-seq, we identified several transcription factors with significant stage specific potential importance in PC differentiation. Interestingly, differentially accessible peaks characterizing the preplasmablastic stage were enriched in motifs of BATF3, FOS and BATF, belonging to activating protein 1 (AP-1) transcription factor family that may represent key transcriptional nodes involved in PC differentiation. Integration of transcriptomic and epigenetic data at the single cell level revealed that a population of preplasmablasts had already undergone epigenetic remodeling related to PC profile together with unfolded protein response activation and are committed to differentiate in PC. These results and the supporting data generated with our in vitro PC differentiation model provide a unique resource for the identification of molecular circuits that are crucial for early and mature PC maturation and biological functions. These data thus provide critical insights into epigenetic- and transcription-mediated reprogramming events that sustain PC differentiation.
Assuntos
Diferenciação Celular , Cromatina , Perfilação da Expressão Gênica , Plasmócitos , Análise de Célula Única , Humanos , Diferenciação Celular/genética , Plasmócitos/metabolismo , Plasmócitos/citologia , Análise de Célula Única/métodos , Cromatina/metabolismo , Cromatina/genética , Transcriptoma , Epigênese Genética , Células CultivadasRESUMO
The differentiation of B cells into plasmablasts (PBs) and then plasma cells (PCs) is associated with extensive cell reprogramming and new cell functions. By using specific inhibition strategies (including a novel morpholino RNA antisense approach), we found that early, sustained upregulation of the proviral integrations of Moloney virus 2 (PIM2) kinase is a pivotal event during human B-cell in vitro differentiation and then continues in mature normal and malignant PCs in the bone marrow. In particular, PIM2 sustained the G1/S transition by acting on CDC25A and p27Kip1 and hindering caspase 3-driven apoptosis through BAD phosphorylation and cytoplasmic stabilization of p21Cip1. In PCs, interleukin-6 triggered PIM2 expression, resulting in antiapoptotic effects on which malignant PCs were particularly dependent. In multiple myeloma, pan-PIM and myeloid cell leukemia-1 (MCL1) inhibitors displayed synergistic activity. Our results highlight a cell-autonomous function that links kinase activity to the newly acquired secretion ability of the PBs and the adaptability observed in both normal and malignant PCs. These findings should finally prompt the reconsideration of PIM2 as a therapeutic target in multiple myeloma.
Assuntos
Mieloma Múltiplo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Plasmócitos/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genéticaRESUMO
Multiple myeloma (MM) is the second most prevalent hematologic malignancy and is incurable because of the inevitable development of drug resistance. Methionine adenosyltransferase 2α (MAT2A) is the primary producer of the methyl donor S-adenosylmethionine (SAM) and several studies have documented MAT2A deregulation in different solid cancers. As the role of MAT2A in MM has not been investigated yet, the aim of this study was to clarify the potential role and underlying molecular mechanisms of MAT2A in MM, exploring new therapeutic options to overcome drug resistance. By analyzing publicly available gene expression profiling data, MAT2A was found to be more highly expressed in patient-derived myeloma cells than in normal bone marrow plasma cells. The expression of MAT2A correlated with an unfavorable prognosis in relapsed patients. MAT2A inhibition in MM cells led to a reduction in intracellular SAM levels, which resulted in impaired cell viability and proliferation, and induction of apoptosis. Further mechanistic investigation demonstrated that MAT2A inhibition inactivated the mTOR-4EBP1 pathway, accompanied by a decrease in protein synthesis. MAT2A targeting in vivo with the small molecule compound FIDAS-5 was able to significantly reduce tumor burden in the 5TGM1 model. Finally, we found that MAT2A inhibition can synergistically enhance the anti-MM effect of the standard-of-care agent bortezomib on both MM cell lines and primary human CD138+ MM cells. In summary, we demonstrate that MAT2A inhibition reduces MM cell proliferation and survival by inhibiting mTOR-mediated protein synthesis. Moreover, our findings suggest that the MAT2A inhibitor FIDAS-5 could be a novel compound to improve bortezomib-based treatment of MM.
Assuntos
Mieloma Múltiplo , S-Adenosilmetionina , Humanos , S-Adenosilmetionina/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Bortezomib/farmacologia , Prognóstico , Serina-Treonina Quinases TOR , Metionina Adenosiltransferase/genética , Metionina Adenosiltransferase/metabolismoRESUMO
We describe the case of a patient with extreme thrombocytosis whose evolution was rapidly fatal. No cause of secondary thrombocytosis was found. There was no sign of myelofibrosis but the megakaryocytes were small and dysplastic. The patient presented a calreticulin (CALR) variant in exon 3 (C105S), as well as concomitant mutations of ASXL1, U2AF1, and EZH2. This variant of CALR has never been described before, and after sorting, all identified mutations were found in myeloid cells but not in lymphoid cells. Therefore, the diagnosis of a frontier case of myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) was made. A treatment with hydroxycarbamide was started because of a high risk of thrombosis. Upon worsening of the hematological status two new mutations appeared, SETBP1 and ETV6, and the CALR mutation was still detectable, as well as the three other mutations found in the chronic stage. Our results show that this variant could contribute to MDS/MPN pathogenesis in that patient.
Assuntos
Doenças Mieloproliferativas-Mielodisplásicas , Transtornos Mieloproliferativos , Mielofibrose Primária , Trombocitose , Humanos , Calreticulina/genética , Calreticulina/metabolismo , Trombocitose/diagnóstico , Mutação , Mielofibrose Primária/genética , Doenças Mieloproliferativas-Mielodisplásicas/complicações , Éxons , Transtornos Mieloproliferativos/genética , Janus Quinase 2/genéticaRESUMO
While multi-drug combinations and continuous treatment have become standard for multiple myeloma, the disease remains incurable. Repurposing drugs that are currently used for other indications could provide a novel approach to improve the therapeutic efficacy of standard multiple myeloma treatments. Here, we assessed the anti-tumor effects of cardiac drugs called ß-blockers as a single agent and in combination with commonly used anti-myeloma therapies. Expression of the ß2 -adrenergic receptor correlated with poor survival outcomes in patients with multiple myeloma. Targeting the ß2 -adrenergic receptor (ß2 AR) using either selective or non-selective ß-blockers reduced multiple myeloma cell viability, and induced apoptosis and autophagy. Blockade of the ß2 AR modulated cancer cell metabolism by reducing the mitochondrial respiration as well as the glycolytic activity. These effects were not observed by blockade of ß1 -adrenergic receptors. Combining ß2 AR blockade with the chemotherapy drug melphalan or the proteasome inhibitor bortezomib significantly increased apoptosis in multiple myeloma cells. These data identify the therapeutic potential of ß2 AR-blockers as a complementary or additive approach in multiple myeloma treatment and support the future clinical evaluation of non-selective ß-blockers in a randomized controlled trial. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 1/uso terapêutico , Transdução de Sinais , Bortezomib/farmacologia , Bortezomib/uso terapêutico , ApoptoseRESUMO
Resistance to chemotherapeutic drugs is a major cause of treatment failure in acute myeloid leukemias (AML). To better characterize the mechanisms of chemoresistance, we first identified genes whose expression is dysregulated in AML cells resistant to daunorubicin or cytarabine, the main drugs used for induction therapy. The genes found to be activated are mostly linked to immune signaling and inflammation. Among them, we identified a strong upregulation of the NOX2 NAPDH oxidase subunit genes (CYBB, CYBA, NCF1, NCF2, NCF4 and RAC2). The ensuing increase in NADPH oxidase expression and production of reactive oxygen species, which is particularly strong in daunorubicin-resistant cells, participates in the acquisition and/or maintenance of resistance to daunorubicin. Gp91phox (CYBB-encoded Nox2 catalytic subunit), was found to be more expressed and active in leukemic cells from patients with the French-American-British (FAB) M4/M5 subtypes of AML than in those from patients with the FAB M0-M2 ones. Moreover, its expression was increased at the surface of patients' chemotherapy-resistant AML cells. Finally, using a gene expression based score we demonstrated that high expression of NOX2 subunit genes is a marker of adverse prognosis in AML patients. The prognostic NOX score we defined is independent of the cytogenetic-based risk classification, FAB subtype, FLT3/NPM1 mutational status and age.
Assuntos
Leucemia Mieloide Aguda , NADPH Oxidase 2 , Humanos , Daunorrubicina , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide Aguda/genética , Prognóstico , NADPH Oxidase 2/genéticaRESUMO
Imbalance in the level of the pyrimidine degradation products dihydrouracil and dihydrothymine is associated with cellular transformation and cancer progression. Dihydropyrimidines are degraded by dihydropyrimidinase (DHP), a zinc metalloenzyme that is upregulated in solid tumors but not in the corresponding normal tissues. How dihydropyrimidine metabolites affect cellular phenotypes remains elusive. Here we show that the accumulation of dihydropyrimidines induces the formation of DNA-protein crosslinks (DPCs) and causes DNA replication and transcriptional stress. We used Xenopus egg extracts to recapitulate DNA replication invitro. We found that dihydropyrimidines interfere directly with the replication of both plasmid and chromosomal DNA. Furthermore, we show that the plant flavonoid dihydromyricetin inhibits human DHP activity. Cellular exposure to dihydromyricetin triggered DPCs-dependent DNA replication stress in cancer cells. This study defines dihydropyrimidines as potentially cytotoxic metabolites that may offer an opportunity for therapeutic-targeting of DHP activity in solid tumors.
Assuntos
Amidoidrolases/genética , Transformação Celular Neoplásica/genética , Replicação do DNA/genética , Transcrição Gênica , Animais , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Uracila/análogos & derivados , Uracila/metabolismo , Xenopus laevis/genética , Xenopus laevis/crescimento & desenvolvimentoRESUMO
Leukocyte-associated immunoglobulin (Ig)-like receptor 1 (LAIR1, CD305) belongs to the family of immune-inhibitory receptors and is widely expressed on hematopoietic mature cells, particularly on immune cells. Four different types of ligands of LAIR1 have been described, including collagens, suggesting a potential immune-regulatory function on the extracellular matrix. By modulating cytokine secretion and cellular functions, LAIR1 displays distinct patterns of expression among NK cell and T/B lymphocyte subsets during their differentiation and cellular activation and plays a major negative immunoregulatory role. Beyond its implications in physiology, the activity of LAIR1 can be inappropriately involved in various autoimmune or inflammatory disorders and has been implicated in cancer physiopathology, including hematological neoplasms. Its action as an inhibitory receptor can result in the dysregulation of immune cellular responses and in immune escape within the tumor microenvironment. Furthermore, when expressed by tumor cells, LAIR1 can modulate their proliferation or invasion properties, with contradictory pro- or anti-tumoral effects depending on tumor type. In this review, we will focus on its role in normal physiological conditions, as well as during pathological situations, including hematological malignancies. We will also discuss potential therapeutic strategies targeting LAIR1 for the treatment of various autoimmune diseases and cancer settings.
Assuntos
Neoplasias Hematológicas , Doenças do Sistema Imunitário , Neoplasias , Humanos , Expressão Gênica , Subpopulações de Linfócitos T , Microambiente TumoralRESUMO
Multiple myeloma (MM) account for approximately 10% of hematological malignancies and is the second most common hematological disorder. Kinases inhibitors are widely used and their efficiency for the treatment of cancers has been demonstrated. Here, in order to identify kinases of potential therapeutic interest for the treatment of MM, we investigated the prognostic impact of the kinome expression profile in large cohorts of patients. We identified 36 kinome-related genes significantly linked with a prognostic value to MM, and built a kinome index based on their expression. The Kinome Index (KI) is linked to prognosis, proliferation, differentiation, and relapse in MM. We then tested inhibitors targeting seven of the identified protein kinas-es (PBK, SRPK1, CDC7-DBF4, MELK, CHK1, PLK4, MPS1/TTK) in human myeloma cell lines. All tested inhibitors significantly reduced the viability of myeloma cell lines, and we confirmed the potential clinical interest of three of them on primary myeloma cells from patients. In addition, we demonstrated their ability to potentialize the toxicity of conventional treatments, including Melphalan and Lenalidomide. This highlights their potential beneficial effect in myeloma therapy. Three kinases inhibitors (CHK1i, MELKi and PBKi) overcome resistance to Lenalidomide, while CHK1, PBK and DBF4 inhibitors re-sensitize Melphalan resistant cell line to this conventional therapeutic agent. Altogether, we demonstrate that kinase inhibitors could be of therapeutic interest especially in high-risk myeloma patients defined by the KI. CHEK1, MELK, PLK4, SRPK1, CDC7-DBF4, MPS1/TTK and PBK inhibitors could represent new treatment options either alone or in combination with Melphalan or IMiD for refractory/relapsing myeloma patients.
Assuntos
Mieloma Múltiplo , Proteínas de Ciclo Celular , Humanos , Fatores Imunológicos , Lenalidomida , Melfalan , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Recidiva Local de Neoplasia , Proteínas Serina-Treonina Quinases/genéticaRESUMO
Cell identity relies on the cross-talk between genetics and epigenetics and their impact on gene expression. Oxidation of 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) is the first step of an active DNA demethylation process occurring mainly at enhancers and gene bodies and, as such, participates in processes governing cell identity in normal and pathological conditions. Although genetic alterations are well documented in multiple myeloma (MM), epigenetic alterations associated with this disease have not yet been thoroughly analyzed. To gain insight into the biology of MM, genome-wide 5hmC profiles were obtained and showed that regions enriched in this modified base overlap with MM enhancers and super enhancers and are close to highly expressed genes. Through the definition of a MM-specific 5hmC signature, we identified FAM72D as a poor prognostic gene located on 1q21, a region amplified in high risk myeloma. We further uncovered that FAM72D functions as part of the FOXM1 transcription factor network controlling cell proliferation and survival and we evidenced an increased sensitivity of cells expressing high levels of FOXM1 and FAM72 to epigenetic drugs targeting histone deacetylases and DNA methyltransferases.
Assuntos
Mieloma Múltiplo , Proteínas/genética , Proliferação de Células/genética , Metilação de DNA , Epigênese Genética , Epigenômica , Humanos , Mieloma Múltiplo/genéticaRESUMO
Plasma cells (PC) are the main effectors of adaptive immunity, responsible for producing antibodies to defend the body against pathogens. They are the result of a complex highly regulated cell differentiation process, taking place in several anatomical locations and involving unique genetic events. Pathologically, PC can undergo tumorigenesis and cause a group of diseases known as plasma cell dyscrasias, including multiple myeloma (MM). MM is a severe disease with poor prognosis that is characterized by the accumulation of malignant PC within the bone marrow, as well as high clinical and molecular heterogeneity. MM patients frequently develop resistance to treatment, leading to relapse. Polycomb group (PcG) proteins are epigenetic regulators involved in cell fate and carcinogenesis. The emerging roles of PcG in PC differentiation and myelomagenesis position them as potential therapeutic targets in MM. Here, we focus on the roles of PcG proteins in normal and malignant plasma cells, as well as their therapeutic implications.
Assuntos
Diferenciação Celular , Hematopoese , Neoplasias/patologia , Plasmócitos/patologia , Proteínas do Grupo Polycomb/metabolismo , Animais , Humanos , Neoplasias/imunologia , Neoplasias/metabolismo , Plasmócitos/imunologia , Plasmócitos/metabolismoRESUMO
BACKGROUND: The aggressive B-cell non-Hodgkin lymphomas diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma (MCL) are characterised by a high proliferation rate. The anaphase-promoting complex/cyclosome (APC/C) and its co-activators Cdc20 and Cdh1 represent an important checkpoint in mitosis. Here, the role of the APC/C and its co-activators is examined in DLBCL and MCL. METHODS: The expression and prognostic value of Cdc20 and Cdh1 was investigated using GEP data and immunohistochemistry. Moreover, the therapeutic potential of APC/C targeting was evaluated using the small-molecule inhibitor proTAME and the underlying mechanisms of action were investigated by western blot. RESULTS: We demonstrated that Cdc20 is highly expressed in DLBCL and aggressive MCL, correlating with a poor prognosis in DLBCL. ProTAME induced a prolonged metaphase, resulting in accumulation of the APC/C-Cdc20 substrate cyclin B1, inactivation/degradation of Bcl-2 and Bcl-xL and caspase-dependent apoptosis. In addition, proTAME strongly enhanced the anti-lymphoma effect of the clinically relevant agents doxorubicin and venetoclax. CONCLUSION: We identified for the first time APC/C as a new, promising target in DLBCL and MCL. Moreover, we provide evidence that Cdc20 might be a novel, independent prognostic factor in DLBCL and MCL.
Assuntos
Ciclossomo-Complexo Promotor de Anáfase/antagonistas & inibidores , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Pró-Fármacos/farmacologia , Tosilarginina Metil Éster/farmacologia , Ciclossomo-Complexo Promotor de Anáfase/metabolismo , Antígenos CD/biossíntese , Antígenos CD/genética , Apoptose/efeitos dos fármacos , Caderinas/biossíntese , Caderinas/genética , Proteínas Cdc20/biossíntese , Proteínas Cdc20/genética , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Linfoma de Célula do Manto/metabolismo , Linfoma de Célula do Manto/patologia , Terapia de Alvo Molecular , Prognóstico , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Células Tumorais CultivadasRESUMO
MicroRNAs (miRNAs) are small noncoding RNAs that attenuate expression of their mRNA targets. Here, we developed a new method and an R package, to easily infer candidate miRNA-mRNA target interactions that could be functional during a given biological process. Using this method, we described, for the first time, a comprehensive integrated analysis of miRNAs and mRNAs during human normal plasma cell differentiation (PCD). Our results reveal 63 miRNAs with significant temporal changes in their expression during normal PCD. We derived a high-confidence network of 295 target relationships comprising 47 miRNAs and 141 targets. These relationships include new examples of miRNAs that appear to coordinately regulate multiple members of critical pathways associated with PCD. Consistent with this, we have experimentally validated a role for the miRNA-30b/c/d-mediated regulation of key PCD factors (IRF4, PRDM1, ELL2 and ARID3A). Furthermore, we found that 24 PCD stage-specific miRNAs are aberrantly overexpressed in multiple myeloma (MM) tumor plasma cells compared to their normal counterpart, suggesting that MM cells frequently acquired expression changes in miRNAs already undergoing dynamic expression modulation during normal PCD. Altogether, our analysis identifies candidate novel key miRNAs regulating networks of significance for normal PCD and malignant plasma cell biology.
Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Mieloma Múltiplo/genética , Plasmócitos/metabolismo , RNA Mensageiro/genética , Diferenciação Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Redes Reguladoras de Genes , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , MicroRNAs/metabolismo , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Plasmócitos/patologia , Fator 1 de Ligação ao Domínio I Regulador Positivo , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Elongação da Transcrição/genética , Fatores de Elongação da Transcrição/metabolismoRESUMO
BACKGROUND: Multiple myeloma (MM) is the second most common hematologic malignancy. Aberrant epigenetic modifications have been reported in MM and could be promising therapeutic targets. As response rates are overall limited but deep responses occur, it is important to identify those patients who could indeed benefit from epigenetic-targeted therapy. METHODS: Since HDACi and DNMTi combination have potential therapeutic value in MM, we aimed to build a GEP-based score that could be useful to design future epigenetic-targeted combination trials. In addition, we investigated the changes in GEP upon HDACi/DNMTi treatment. RESULTS: We report a new gene expression-based score to predict MM cell sensitivity to the combination of DNMTi/HDACi. A high Combo score in MM patients identified a group with a worse overall survival but a higher sensitivity of their MM cells to DNMTi/HDACi therapy compared to a low Combo score. In addition, treatment with DNMTi/HDACi downregulated IRF4 and MYC expression and appeared to induce a mature BMPC plasma cell gene expression profile in myeloma cell lines. CONCLUSION: In conclusion, we developed a score for the prediction of primary MM cell sensitivity to DNMTi/HDACi and found that this combination could be beneficial in high-risk patients by targeting proliferation and inducing maturation.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Reprogramação Celular/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/administração & dosagem , Mieloma Múltiplo/tratamento farmacológico , Plasmócitos/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Reprogramação Celular/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Análise em Microsséries , Terapia de Alvo Molecular/métodos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Plasmócitos/fisiologia , Projetos de Pesquisa , Transcriptoma , Células Tumorais CultivadasRESUMO
BACKGROUND: Multiple myeloma (MM) is an incurable clonal plasma cell malignancy. The constitutive expression of HIF-1α in MM suggests that inhibition of HIF-1α-mediated transcription represents an interesting target in MM. METHODS: As p300 is a crucial co-activator of hypoxia-inducible transcription, disrupting the complex HIF-1α/p300 to target HIF activity appears to be an attractive strategy. RESULTS: We reported that chetomin, an inhibitor of HIF-1α/p300 interaction, exhibits antitumour activity in human myeloma cell lines and primary MM cells from patients. CONCLUSIONS: Our data suggest that chetomin may be of clinical value in MM and especially for patients characterised by a high EP300/HIF-1α expression and a poor prognosis.
Assuntos
Proliferação de Células/efeitos dos fármacos , Dissulfetos/farmacologia , Proteína p300 Associada a E1A/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Alcaloides Indólicos/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Perfilação da Expressão Gênica , Humanos , Terapia de Alvo Molecular , Mieloma Múltiplo/genética , PrognósticoRESUMO
Annexin A2 (ANXA2) promotes myeloma cell growth, reduces apoptosis in myeloma cell lines, and increases osteoclast formation. ANXA2 has been described in small cohorts of samples as expressed by myeloma cells and cells of the BM microenvironment. To investigate its clinical role, we assessed 1148 samples including independent cohorts of 332 and 701 CD138-purified myeloma cell samples from previously untreated patients together with clinical prognostic factors, chromosomal aberrations, and gene expression-based high-risk scores, along with expression of ANXA2 in whole BM samples, stromal cells, osteoblasts, osteoclasts, and BM sera. ANXA2 is expressed in all normal and malignant plasma cell samples. Higher ANXA2 expression in myeloma cells is associated with significantly inferior event-free and overall survival independently of conventional prognostic factors and is associated with gene expression-determined high risk and high proliferation. Within the BM, all cell populations, including osteoblasts, osteoclasts, and stromal cells, express ANXA2. ANXA2 expression is increased significantly in myelomatous versus normal BM serum. ANXA2 exemplifies an interesting class of targetable bone-remodeling factors expressed by normal and malignant plasma cells and the BM microenvironment that have a significant impact on survival of myeloma patients.
Assuntos
Anexina A2/fisiologia , Mieloma Múltiplo/diagnóstico , Anexina A2/genética , Anexina A2/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Biomarcadores Tumorais/fisiologia , Doenças Ósseas/diagnóstico , Doenças Ósseas/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Estudos de Associação Genética , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Prognóstico , Receptores de Peptídeos/genética , Receptores de Peptídeos/metabolismo , Fatores de Risco , Análise de Sobrevida , Microambiente Tumoral/genética , Estudos de Validação como AssuntoRESUMO
BACKGROUND: Multiparametric flow cytometry (MFC) is an essential diagnostic tool in B acute lymphoblastic leukemia (B ALL) to determine the B-lineage affiliation of the blast population and to define their complete immunophenotypic profile. Most MFC strategies used in routine laboratories include leukemia-associated phenotype (LAP) markers, whose expression profiles can be difficult to interpret. The aim of our study was to reach a better understanding of 7 LAP markers' landscape in B ALL: CD9, CD21, CD66c, CD58, CD81, CD123, and NG2. METHODS: Using a 10-color MFC approach, we evaluated the level of expression of 7 LAP markers including CD9, CD21, CD66c, CD58, CD81, CD123, and NG2, at the surface of normal peripheral blood leukocytes (n = 10 healthy donors), of normal precursor B regenerative cells (n = 40 uninvolved bone marrow samples) and of lymphoblasts (n = 100 peripheral blood samples or bone marrow samples from B ALL patients at diagnosis). The expression profile of B lymphoblasts was analyzed according the presence or absence of recurrent cytogenetic aberrations. The prognostic value of the 7 LAP markers was examined using Maxstat R algorithm. RESULTS: In order to help the interpretation of the MFC data in routine laboratories, we first determined internal positive and negative populations among normal leukocytes for each of the seven evaluated LAP markers. Second, their profile of expression was evaluated in normal B cell differentiation in comparison with B lymphoblasts to establish a synopsis of their expression in normal hematogones. We then evaluated the frequency of expression of these LAP markers at the surface of B lymphoblasts at diagnosis of B ALL. CD9 was expressed in 60% of the cases, CD21 in only 3% of the cases, CD58 in 96% of the cases, CD66c in 45% of the cases, CD81 in 97% of the cases, CD123 in 72% of the cases, and NG2 in only 2% of the cases. We confirmed the interest of the CD81/CD58 MFI expression ratio as a way to discriminate hematogones from lymphoblasts. We observed a significant lower expression of CD9 and of CD81 at the surface of B lymphoblasts with a t(9;22)(BCR-ABL) in comparison with B lymphoblasts without any recurrent cytogenetic alteration (p = 0.0317 and p = 0.0011, respectively) and with B lymphoblasts harboring other cytogenetic recurrent abnormalities (p = 0.0032 and p < 0.0001, respectively). B lymphoblasts with t(1;19) at diagnosis significantly overexpressed CD81 when compared with B lymphoblasts with other recurrent cytogenetic abnormalities or without any recurrent alteration (p = 0.0001). An overexpression of CD58 was also observed in the cases harboring this abnormal cytogenetic event, when compared with B lymphoblasts with other recurrent cytogenetic abnormalities (p = 0.030), or without any recurrent alteration (p = 0.0002). In addition, a high expression of CD123, of CD58 and of CD81 was associated with a favorable prognosis in our cohort of pediatric and young adult B ALL patients. We finally built a risk score based on the expression of these 3 LAP markers, this scoring approach being able to split these patients into a high-risk group (17%) and a better outcome group (83%, p < 0.0001). CONCLUSION: The complexity of the phenotypic signature of lymphoblasts at diagnosis of B ALL is illustrated by the variability in the expression of LAP antigens. Knowledge of the expression levels of these markers in normal leukocytes and during normal B differentiation is crucial for an optimal interpretation of diagnostic cytometry results and serves as a basis for the biological follow-up of B ALL.
Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adulto Jovem , Humanos , Criança , Subunidade alfa de Receptor de Interleucina-3 , Citometria de Fluxo , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Aberrações CromossômicasRESUMO
PURPOSE: Given the high heterogeneity in survival for patients with multiple myeloma, it would be clinically useful to quantitatively predict the individual survival instead of attributing patients to two to four risk groups as in current models, for example, revised International Staging System (R-ISS), R2-ISS, or Mayo-2022-score. PATIENTS AND METHODS: Our aim was to develop a quantitative prediction tool for individual patient's 3-/5-year overall survival (OS) probability. We integrated established clinical and molecular risk factors into a comprehensive prognostic model and evaluated and validated its risk discrimination capabilities versus R-ISS, R2-ISS, and Mayo-2022-score. RESULTS: A nomogram for estimating OS probabilities was built on the basis of a Cox regression model. It allows one to translate the individual risk profile of a patient into 3-/5-year OS probabilities by attributing points to each prognostic factor and summing up all points. The nomogram was externally validated regarding discrimination and calibration. There was no obvious bias or overfitting of the prognostic index on the validation cohort. Resampling-based and external evaluation showed good calibration. The c-index of the model was similar on the training (0.76) and validation cohort (0.75) and significantly higher than for the R-ISS (P < .001) or R2-ISS (P < .01). CONCLUSION: In summary, we developed and validated individual quantitative nomogram-based OS prediction. Continuous risk assessment integrating molecular prognostic factors is superior to R-ISS, R2-ISS, or Mayo-2022-score alone.