RESUMEN
The origin and specification of human dendritic cells (DCs) have not been investigated at the clonal level. Through the use of clonal assays, combined with statistical computation, to quantify the yield of granulocytes, monocytes, lymphocytes and three subsets of DCs from single human CD34+ progenitor cells, we found that specification to the DC lineage occurred in parallel with specification of hematopoietic stem cells (HSCs) to the myeloid and lymphoid lineages. This started as a lineage bias defined by specific transcriptional programs that correlated with the combinatorial 'dose' of the transcription factors IRF8 and PU.1, which was transmitted to most progeny cells and was reinforced by upregulation of IRF8 expression driven by the hematopoietic cytokine FLT3L during cell division. We propose a model in which specification to the DC lineage is driven by parallel and inheritable transcriptional programs in HSCs and is reinforced over cell division by recursive interactions between transcriptional programs and extrinsic signals.
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Linaje de la Célula , Células Dendríticas/citología , Células Madre Hematopoyéticas/citología , Factores Reguladores del Interferón/metabolismo , Leucopoyesis , Células Madre Multipotentes/citología , Animales , Diferenciación Celular , Sangre Fetal , Citometría de Flujo , Humanos , Factores Reguladores del Interferón/genética , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Análisis de Componente Principal , Proteínas Proto-Oncogénicas/metabolismo , Transactivadores/metabolismo , Regulación hacia ArribaRESUMEN
Cell surface growth factor receptors couple environmental cues to the regulation of cytoplasmic homeostatic processes, including autophagy, and aberrant activation of such receptors is a common feature of human malignancies. Here, we defined the molecular basis by which the epidermal growth factor receptor (EGFR) tyrosine kinase regulates autophagy. Active EGFR binds the autophagy protein Beclin 1, leading to its multisite tyrosine phosphorylation, enhanced binding to inhibitors, and decreased Beclin 1-associated VPS34 kinase activity. EGFR tyrosine kinase inhibitor (TKI) therapy disrupts Beclin 1 tyrosine phosphorylation and binding to its inhibitors and restores autophagy in non-small-cell lung carcinoma (NSCLC) cells with a TKI-sensitive EGFR mutation. In NSCLC tumor xenografts, the expression of a tyrosine phosphomimetic Beclin 1 mutant leads to reduced autophagy, enhanced tumor growth, tumor dedifferentiation, and resistance to TKI therapy. Thus, oncogenic receptor tyrosine kinases directly regulate the core autophagy machinery, which may contribute to tumor progression and chemoresistance.
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Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia , Resistencia a Antineoplásicos , Receptores ErbB/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis/genética , Beclina-1 , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Línea Celular Tumoral , Receptores ErbB/genética , Xenoinjertos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos NOD , Ratones SCID , Trasplante de Neoplasias , FosforilaciónRESUMEN
Paneth cells (PCs), a specialized secretory cell type in the small intestine, are increasingly recognized as having an essential role in host responses to microbiome and environmental stresses. Whether and how commensal and pathogenic microbes modify PC composition to modulate inflammation remain unclear. Using newly developed PC-reporter mice under conventional and gnotobiotic conditions, we determined PC transcriptomic heterogeneity in response to commensal and invasive microbes at single cell level. Infection expands the pool of CD74+ PCs, whose number correlates with auto or allogeneic inflammatory disease progressions in mice. Similar correlation was found in human inflammatory disease tissues. Infection-stimulated cytokines increase production of reactive oxygen species (ROS) and expression of a PC-specific mucosal pentraxin (Mptx2) in activated PCs. A PC-specific ablation of MyD88 reduced CD74+ PC population, thus ameliorating pathogen-induced systemic disease. A similar phenotype was also observed in mice lacking Mptx2. Thus, infection stimulates expansion of a PC subset that influences disease progression.
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Microbiota , Células de Paneth , Humanos , Animales , Ratones , Células de Paneth/metabolismo , Células de Paneth/patología , Intestino Delgado , Inflamación/patología , Citocinas/metabolismoRESUMEN
The DNA-dependent protein kinase (DNA-PK), which comprises the KU heterodimer and a catalytic subunit (DNA-PKcs), is a classical non-homologous end-joining (cNHEJ) factor1. KU binds to DNA ends, initiates cNHEJ, and recruits and activates DNA-PKcs. KU also binds to RNA, but the relevance of this interaction in mammals is unclear. Here we use mouse models to show that DNA-PK has an unexpected role in the biogenesis of ribosomal RNA (rRNA) and in haematopoiesis. The expression of kinase-dead DNA-PKcs abrogates cNHEJ2. However, most mice that both expressed kinase-dead DNA-PKcs and lacked the tumour suppressor TP53 developed myeloid disease, whereas all other previously characterized mice deficient in both cNHEJ and TP53 expression succumbed to pro-B cell lymphoma3. DNA-PK autophosphorylates DNA-PKcs, which is its best characterized substrate. Blocking the phosphorylation of DNA-PKcs at the T2609 cluster, but not the S2056 cluster, led to KU-dependent defects in 18S rRNA processing, compromised global protein synthesis in haematopoietic cells and caused bone marrow failure in mice. KU drives the assembly of DNA-PKcs on a wide range of cellular RNAs, including the U3 small nucleolar RNA, which is essential for processing of 18S rRNA4. U3 activates purified DNA-PK and triggers phosphorylation of DNA-PKcs at T2609. DNA-PK, but not other cNHEJ factors, resides in nucleoli in an rRNA-dependent manner and is co-purified with the small subunit processome. Together our data show that DNA-PK has RNA-dependent, cNHEJ-independent functions during ribosome biogenesis that require the kinase activity of DNA-PKcs and its phosphorylation at the T2609 cluster.
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Proteínas de Unión al Calcio/metabolismo , Hematopoyesis/genética , Autoantígeno Ku/metabolismo , Linfoma/enzimología , Linfoma/fisiopatología , ARN Ribosómico 18S/metabolismo , Proteínas de Unión al Calcio/genética , Dominio Catalítico/fisiología , Reparación del ADN/genética , Activación Enzimática/genética , Células HeLa , Humanos , Linfoma/genética , Modelos Animales , Mutación , Fosforilación , Unión Proteica , Biosíntesis de Proteínas/genética , ARN Ribosómico 18S/genética , ARN Nucleolar Pequeño/metabolismoRESUMEN
Heterozygous inactivating mutations of the KMT2D methyltransferase and the CREBBP acetyltransferase are among the most common genetic alterations in B cell lymphoma and co-occur in 40 to 60% of follicular lymphoma (FL) and 30% of EZB/C3 diffuse large B cell lymphoma (DLBCL) cases, suggesting they may be coselected. Here, we show that combined germinal center (GC)-specific haploinsufficiency of Crebbp and Kmt2d synergizes in vivo to promote the expansion of abnormally polarized GCs, a common preneoplastic event. These enzymes form a biochemical complex on select enhancers/superenhancers that are critical for the delivery of immune signals in the GC light zone and are only corrupted upon dual Crebbp/Kmt2d loss, both in mouse GC B cells and in human DLBCL. Moreover, CREBBP directly acetylates KMT2D in GC-derived B cells, and, consistently, its inactivation by FL/DLBCL-associated mutations abrogates its ability to catalyze KMT2D acetylation. Genetic and pharmacologic loss of CREBBP and the consequent decrease in KMT2D acetylation lead to reduced levels of H3K4me1, supporting a role for this posttranslational modification in modulating KMT2D activity. Our data identify a direct biochemical and functional interaction between CREBBP and KMT2D in the GC, with implications for their role as tumor suppressors in FL/DLBCL and for the development of precision medicine approaches targeting enhancer defects induced by their combined loss.
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Linfoma Folicular , Linfoma de Células B Grandes Difuso , Animales , Humanos , Ratones , Acetilación , Linfocitos B/metabolismo , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Centro Germinal , Linfoma Folicular/genética , Linfoma Folicular/metabolismo , Linfoma Folicular/patología , Linfoma de Células B Grandes Difuso/patología , Mutación , Procesamiento Proteico-PostraduccionalRESUMEN
Nonresponsive celiac disease (CeD) is relatively common. It is generally attributed to persistent gluten exposure and resolves after correction of diet errors. However, other complications of CeD and disorders clinically mimicking CeD need to be excluded. Novel therapies are being evaluated to facilitate mucosal recovery, which might benefit patients with nonresponsive CeD. Refractory CeD (RCeD) is rare and is divided into 2 types. The etiology of type I RCeD is unclear. A switch to gluten-independent autoimmunity is suspected in some patients. In contrast, type II RCeD represents a low-grade intraepithelial lymphoma. Type I RCeD remains a diagnosis of exclusion, requiring ruling out gluten intake and other nonmalignant causes of villous atrophy. Diagnosis of type II RCeD relies on the demonstration of a clonal population of neoplastic intraepithelial lymphocytes with an atypical immunophenotype. Type I RCeD and type II RCeD generally respond to open-capsule budesonide, but the latter has a dismal prognosis due to severe malnutrition and frequent progression to enteropathy-associated T-cell lymphoma; more efficient therapy is needed.
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Enfermedad Celíaca , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/terapia , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/dietoterapia , Humanos , Dieta Sin Gluten , Mucosa Intestinal/patología , Mucosa Intestinal/inmunología , Mucosa Intestinal/efectos de los fármacos , Glútenes/inmunología , Glútenes/efectos adversos , Resultado del Tratamiento , Budesonida/uso terapéuticoRESUMEN
Adult T-cell leukemia-lymphoma (ATLL) is an aggressive Human T-cell Leukemia Virus Type 1 (HTLV-1)-driven malignancy. Although Western hemisphere (Afro-Caribbean and South American) patients face worse prognoses, our understanding of ATLL molecular drivers derives mostly from Japanese studies. We performed multi-omic analyses to elucidate the genomic landscape of ATLL in Western cohorts. Recurrent deletion and/or damaging mutations involving FOXO3, ANKRD11, DGKZ, and PTPN6 implicate these genes as potential tumor suppressors. RNA-seq, published functional data and in vitro assays support the roles of ANKRD11 and FOXO3 as regulators of T-cell proliferation and apoptosis in ATLL, respectively. Survival data suggest ANKRD11 mutation may confer a worse prognosis. Japanese and Western cohorts, in addition to acute and lymphomatous subtypes, demonstrated distinct molecular patterns. GATA3 deletion was associated with unfavorable chronic cases. IRF4 and CARD11 mutations frequently emerged in relapses after interferon therapy. Our findings reveal novel putative ATLL driver genes and clinically relevant differences between Japanese and Western ATLL patients.
RESUMEN
Plasmacytoid dendritic cells (pDCs) are primary producers of type I interferon (IFN) in response to viruses. The IFN-producing capacity of pDCs is regulated by specific inhibitory receptors, yet none of the known receptors are conserved in evolution. We report that within the human immune system, receptor protein tyrosine phosphatase sigma (PTPRS) is expressed specifically on pDCs. Surface PTPRS was rapidly downregulated after pDC activation, and only PTPRS(-) pDCs produced IFN-α. Antibody-mediated PTPRS crosslinking inhibited pDC activation, whereas PTPRS knockdown enhanced IFN response in a pDC cell line. Similarly, murine Ptprs and the homologous receptor phosphatase Ptprf were specifically co-expressed in murine pDCs. Haplodeficiency or DC-specific deletion of Ptprs on Ptprf-deficient background were associated with enhanced IFN response of pDCs, leukocyte infiltration in the intestine and mild colitis. Thus, PTPRS represents an evolutionarily conserved pDC-specific inhibitory receptor, and is required to prevent spontaneous IFN production and immune-mediated intestinal inflammation.
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Colitis/inmunología , Células Dendríticas/inmunología , Intestinos/inmunología , Leucocitos/fisiología , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/metabolismo , Animales , Diferenciación Celular , Movimiento Celular/genética , Células Cultivadas , Colitis/genética , Modelos Animales de Enfermedad , Humanos , Interferón gamma/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Tirosina Fosfatasas Clase 2 Similares a Receptores/genéticaRESUMEN
In this Letter, the graphs in Fig. 2a and c were inadvertently the same owing to a copy and paste error from the original graphs in Prism. The Source Data files containing the raw data were correct. Fig. 2c has been corrected online.
RESUMEN
Autophagy increases the lifespan of model organisms; however, its role in promoting mammalian longevity is less well-established1,2. Here we report lifespan and healthspan extension in a mouse model with increased basal autophagy. To determine the effects of constitutively increased autophagy on mammalian health, we generated targeted mutant mice with a Phe121Ala mutation in beclin 1 (Becn1F121A/F121A) that decreases its interaction with the negative regulator BCL2. We demonstrate that the interaction between beclin 1 and BCL2 is disrupted in several tissues in Becn1 F121A/F121A knock-in mice in association with higher levels of basal autophagic flux. Compared to wild-type littermates, the lifespan of both male and female knock-in mice is significantly increased. The healthspan of the knock-in mice also improves, as phenotypes such as age-related renal and cardiac pathological changes and spontaneous tumorigenesis are diminished. Moreover, mice deficient in the anti-ageing protein klotho 3 have increased beclin 1 and BCL2 interaction and decreased autophagy. These phenotypes, along with premature lethality and infertility, are rescued by the beclin 1(F121A) mutation. Together, our data demonstrate that disruption of the beclin 1-BCL2 complex is an effective mechanism to increase autophagy, prevent premature ageing, improve healthspan and promote longevity in mammals.
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Envejecimiento/fisiología , Autofagia/fisiología , Beclina-1/metabolismo , Longevidad/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Envejecimiento/genética , Animales , Autofagosomas/metabolismo , Beclina-1/genética , Células Cultivadas , Femenino , Fibroblastos/citología , Técnicas de Sustitución del Gen , Glucuronidasa/deficiencia , Glucuronidasa/genética , Células HeLa , Salud , Humanos , Proteínas Klotho , Longevidad/genética , Masculino , Ratones , Ratones Endogámicos C57BL , MutaciónRESUMEN
Fifty percent of diffuse large B cell lymphoma (DLBCL) cases lack cell-surface expression of the class I major histocompatibility complex (MHC-I), thus escaping recognition by cytotoxic T cells. Here we show that, across B cell lymphomas, loss of MHC-I, but not MHC-II, is preferentially restricted to DLBCL. To identify the involved mechanisms, we performed whole exome and targeted HLA deep-sequencing in 74 DLBCL samples, and found somatic inactivation of B2M and the HLA-I loci in 80% (34 of 42) of MHC-INEG tumors. Furthermore, 70% (22 of 32) of MHC-IPOS DLBCLs harbored monoallelic HLA-I genetic alterations (MHC-IPOS/mono), indicating allele-specific inactivation. MHC-INEG and MHC-IPOS/mono cases harbored significantly higher mutational burden and inferred neoantigen load, suggesting potential coselection of HLA-I loss and sustained neoantigen production. Notably, the analysis of >500,000 individuals across different cancer types revealed common germline HLA-I homozygosity, preferentially in DLBCL. In mice, germinal-center B cells lacking HLA-I expression did not progress to lymphoma and were counterselected in the context of oncogene-driven lymphomagenesis, suggesting that additional events are needed to license immune evasion. These results suggest a multistep process of HLA-I loss in DLBCL development including both germline and somatic events, and have direct implications for the pathogenesis and immunotherapeutic targeting of this disease.
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Transformación Celular Neoplásica/genética , Antígenos de Histocompatibilidad Clase I/genética , Linfoma de Células B Grandes Difuso/genética , Línea Celular Tumoral , Citidina Desaminasa , Silenciador del Gen , Humanos , Linfoma de Células B Grandes Difuso/inmunología , Proteínas Proto-Oncogénicas c-bcl-6/genética , Microglobulina beta-2/genéticaRESUMEN
Peripheral T-cell lymphomas (PTCLs) are uniquely vulnerable to epigenetic modifiers. We demonstrated in vitro synergism between histone deacetylase inhibitors and DNA methyltransferase inhibitors in preclinical models of T-cell lymphoma. In a phase 1 trial, we found oral 5-azacytidine and romidepsin to be safe and effective, with lineage-selective activity among patients with relapsed/refractory (R/R) PTCL. Patients who were treatment naïve or who had R/R PTCL received azacytidine 300 mg once per day on days 1 to 14, and romidepsin 14 mg/m2 on days 8, 15, and 22 every 35 days. The primary objective was overall response rate (ORR). Targeted next-generation sequencing was performed on tumor samples to correlate mutational profiles and response. Among 25 enrolled patients, the ORR and complete response rates were 61% and 48%, respectively. However, patients with T-follicular helper cell (tTFH) phenotype exhibited higher ORR (80%) and complete remission rate (67%). The most frequent grade 3 to 4 adverse events were thrombocytopenia (48%), neutropenia (40%), lymphopenia (32%), and anemia (16%). At a median follow-up of 13.5 months, the median progression-free survival, duration of response, and overall survival were 8.0 months, 20.3 months, and not reached, respectively. The median progression-free survival and overall survival were 8.0 months and 20.6 months, respectively, in patients with R/R disease. Patients with tTFH enjoyed a particularly long median survival (median not reached). Responders harbored a higher average number of mutations in genes involved in DNA methylation and histone deacetylation. Combined azacytidine and romidepsin are highly active in PTCL patients and could serve as a platform for novel regimens in this disease. This trial was registered at www.clinicaltrials.gov as #NCT01998035.
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Antibióticos Antineoplásicos/uso terapéutico , Azacitidina/uso terapéutico , Depsipéptidos/uso terapéutico , Inhibidores de Histona Desacetilasas/uso terapéutico , Linfoma de Células T Periférico/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Azacitidina/administración & dosificación , Azacitidina/efectos adversos , Metilación de ADN/efectos de los fármacos , Depsipéptidos/administración & dosificación , Depsipéptidos/efectos adversos , Femenino , Inhibidores de Histona Desacetilasas/administración & dosificación , Inhibidores de Histona Desacetilasas/efectos adversos , Humanos , Linfoma de Células T Periférico/genética , Masculino , Persona de Mediana Edad , Mutación/efectos de los fármacos , Resultado del TratamientoRESUMEN
OBJECTIVES: Coeliac disease (CD) is a complex autoimmune disorder that develops in genetically susceptible individuals. Dietary gluten triggers an immune response for which the only available treatment so far is a strict, lifelong gluten free diet. Human leucocyte antigen (HLA) genes and several non-HLA regions have been associated with the genetic susceptibility to CD, but their role in the pathogenesis of the disease is still essentially unknown, making it complicated to develop much needed non-dietary treatments. Here, we describe the functional involvement of a CD-associated single-nucleotide polymorphism (SNP) located in the 5'UTR of XPO1 in the inflammatory environment characteristic of the coeliac intestinal epithelium. DESIGN: The function of the CD-associated SNP was investigated using an intestinal cell line heterozygous for the SNP, N6-methyladenosine (m6A)-related knock-out and HLA-DQ2 mice, and human samples from patients with CD. RESULTS: Individuals harbouring the risk allele had higher m6A methylation in the 5'UTR of XPO1 RNA, rendering greater XPO1 protein amounts that led to downstream nuclear factor kappa B (NFkB) activity and subsequent inflammation. Furthermore, gluten exposure increased overall m6A methylation in humans as well as in in vitro and in vivo models. CONCLUSION: We identify a novel m6A-XPO1-NFkB pathway that is activated in CD patients. The findings will prompt the development of new therapeutic approaches directed at m6A proteins and XPO1, a target under evaluation for the treatment of intestinal disorders.
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Enfermedad Celíaca/genética , Carioferinas/genética , Polimorfismo de Nucleótido Simple , ARN/metabolismo , Receptores Citoplasmáticos y Nucleares/genética , Adenosina/análogos & derivados , Adenosina/genética , Animales , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales/patología , Antígenos HLA-DQ/genética , Humanos , Mucosa Intestinal/patología , Metilación , Ratones Noqueados , FN-kappa B/metabolismo , Proteína Exportina 1RESUMEN
Plasmablastic lymphoma (PBL) is a rare and clinically aggressive neoplasm that typically occurs in immunocompromised individuals, including those with HIV infection and solid organ allograft recipients. Most prior studies have focused on delineating the clinicopathologic features and genetic attributes of HIV-related PBLs, where MYC deregulation and EBV infection, and more recently, mutations in JAK/STAT, MAP kinase, and NOTCH pathway genes have been implicated in disease pathogenesis. The phenotypic spectrum of post-transplant (PT)-PBLs is not well characterized and data on underlying genetic alterations are limited. Hence, we performed comprehensive histopathologic and immunophenotypic evaluation and targeted sequencing of 18 samples from 11 patients (8 males, 3 females, age range 12-76 years) with PT-PBL; 8 de novo and 3 preceded by other types of PTLDs. PT-PBLs displayed morphologic and immunophenotypic heterogeneity and some features overlapped those of plasmablastic myeloma. Six (55%) cases were EBV+ and 5 (45%) showed MYC rearrangement by fluorescence in situ hybridization. Recurrent mutations in epigenetic regulators (KMT2/MLL family, TET2) and DNA damage repair and response (TP53, mismatch repair genes, FANCA, ATRX), MAP kinase (KRAS, NRAS, HRAS, BRAF), JAK/STAT (STAT3, STAT6, SOCS1), NOTCH (NOTCH1, NOTCH3, SPEN), and immune surveillance (FAS, CD58) pathway genes were observed, with EBV+ and EBV- cases exhibiting similarities and differences in their mutational profiles. Clinical outcomes also varied, with survival ranging from 0-15.9 years postdiagnosis. Besides uncovering the biological heterogeneity of PT-PBL, our study highlights similarities and distinctions between PT-PBLs and PBLs occurring in other settings and reveals potentially targetable oncogenic pathways in disease subsets.
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Infecciones por Virus de Epstein-Barr , Infecciones por VIH , Linfoma Plasmablástico , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Inmunofenotipificación , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Linfoma Plasmablástico/etiología , Linfoma Plasmablástico/genética , Adulto JovenAsunto(s)
Enfermedad de Castleman , Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Enfermedad de Castleman/patología , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/virología , Masculino , Ganglios Linfáticos/patología , Persona de Mediana Edad , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/patología , FemeninoRESUMEN
The peripheral T-cell lymphomas (PTCLs) are uniquely sensitive to epigenetic modifiers. Based on the synergism between histone deacetylase inhibitors and hypomethylating agents that we established in preclinical PTCL models, we conducted a phase 1 study of oral 5-azacytidine (AZA) and romidepsin (ROMI) in patients with advanced lymphoid malignancies, with emphasis on PTCL. According to a 3 + 3 design, patients were assigned to 1 of 7 cohorts with AZA doses ranging from 100 mg daily on days 1 to 14 to 300 mg daily on days 1 to 21, ROMI doses ranging from 10 mg/m2 on days 8 and 15 to 14 mg/m2 on days 8, 15, and 22, with cycles of 21 to 35 days. Coprimary end points included maximum tolerated dose (MTD) and dose-limiting toxicity (DLT). We treated a total of 31 patients. The MTD was AZA 300 mg on days 1 to 14 and ROMI 14 mg/m2 on days 8, 15, and 22 on a 35-day cycle. DLTs included grade 4 thrombocytopenia, prolonged grade 3 thrombocytopenia, grade 4 neutropenia, and pleural effusion. There were no treatment-related deaths. The combination was substantially more active in patients with PTCL than in those with non-T-cell lymphoma. The overall response rate in all, non-T-cell, and T-cell lymphoma patients was 32%, 10%, and 73%, respectively, and the complete response rates were 23%, 5%, and 55%, respectively. We did not find an association between response and level of demethylation or tumor mutational profile. This study establishes that combined epigenetic modifiers are potently active in PTCL patients. This trial was registered at www.clinicaltrials.gov as NCT01998035.
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Antibióticos Antineoplásicos/uso terapéutico , Depsipéptidos/uso terapéutico , Linfoma de Células T/tratamiento farmacológico , Adulto , Anciano , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Depsipéptidos/administración & dosificación , Depsipéptidos/efectos adversos , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto JovenRESUMEN
Burkitt lymphoma (BL) is an aggressive, MYC-driven lymphoma comprising 3 distinct clinical subtypes: sporadic BLs that occur worldwide, endemic BLs that occur predominantly in sub-Saharan Africa, and immunodeficiency-associated BLs that occur primarily in the setting of HIV. In this study, we comprehensively delineated the genomic basis of BL through whole-genome sequencing (WGS) of 101 tumors representing all 3 subtypes of BL to identify 72 driver genes. These data were additionally informed by CRISPR screens in BL cell lines to functionally annotate the role of oncogenic drivers. Nearly every driver gene was found to have both coding and non-coding mutations, highlighting the importance of WGS for identifying driver events. Our data implicate coding and non-coding mutations in IGLL5, BACH2, SIN3A, and DNMT1. Epstein-Barr virus (EBV) infection was associated with higher mutation load, with type 1 EBV showing a higher mutational burden than type 2 EBV. Although sporadic and immunodeficiency-associated BLs had similar genetic profiles, endemic BLs manifested more frequent mutations in BCL7A and BCL6 and fewer genetic alterations in DNMT1, SNTB2, and CTCF. Silencing mutations in ID3 were a common feature of all 3 subtypes of BL. In vitro, mass spectrometry-based proteomics demonstrated that the ID3 protein binds primarily to TCF3 and TCF4. In vivo knockout of ID3 potentiated the effects of MYC, leading to rapid tumorigenesis and tumor phenotypes consistent with those observed in the human disease.
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Linfoma de Burkitt/genética , Secuenciación Completa del Genoma/métodos , Animales , Humanos , RatonesRESUMEN
Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin's lymphoma, and it constitutes biologically heterogeneous entities. Standard first-line therapies cure ~60% of patients, the rest being either refractory or experiencing relapse. Currently, there are no robust predictive biomarkers of therapeutic response. Heterogeneity of DLBCL is partly explained by the cell of origin (COO), ie, germinal centre B cell or activated B cell, with the latter exhibiting worse prognosis. While gene expression profiling (GEP) is the gold standard for determining COO, surrogate immunohistochemical algorithms are used clinically, but show significant discordance with GEP. Recently, additional genetic subgroups with different prognoses have been reported. However, the tools/expertise required for analysis prohibit widespread deployment. Liquid biopsy-based assays show promise in providing clinically actionable information, are noninvasive and facilitate serial sampling to assess mechanisms of therapy resistance. Circulating, cell-free DNA analysis has shown enhanced sensitivity for detecting molecular alterations, but this modality cannot determine alterations of the tumor proteome or on signalling pathways. Exosomes are endosomally derived vesicles, are found in high abundance in body fluids and are readily isolated using a variety of methods. Tumour-derived exosomes can yield data regarding genetic, transcriptional, and proteomic changes useful for diagnosis, prognosis, and therapy of DLBCL. At present, standardized techniques for isolating exosomes are lacking and discriminating between exosomes from neoplastic and normal B cells is challenging. Refinements in isolation procedures are required to realize their full potential as precision medicine tools to provide comprehensive information on disease subtypes, identify prognostic factors, allow real-time monitoring of therapy response and delineate novel drug targets.