RESUMEN
Myelodysplastic neoplasms (MDS) are characterized by clonal evolution starting from the compartment of hematopoietic stem and progenitors cells (HSPCs), leading in some cases to leukemic transformation. We hypothesized that deciphering the diversity of the HSPCs compartment may allow for the early detection of an emergent sub-clone that drives disease progression. Deep analysis of HSPCs repartition by multiparametric flow cytometry revealed a strong disorder of the hematopoietic branching system in most patients at diagnosis with different phenotypic signatures closely related to specific MDS features. In two independent cohorts of 131 and 584 MDS, the HSPCs heterogeneity quantified through entropy calculation was decreased in 47% and 46% of cases, reflecting a more advanced state of the disease with deeper cytopenias, higher IPSS-R risk and accumulation of somatic mutations. We demonstrated that patients with lower-risk MDS and low CD34 + CD38+HSPCs entropy had an adverse outcome and that this parameter is as an independent predictive biomarker for progression free survival, leukemia free survival and overall survival. Analysis of HSPCs repartition at diagnosis represents therefore a very powerful tool to identify lower-risk MDS patients with a worse outcome and valuable for clinical decision-making, which could be fully integrated in the MDS diagnostic workflow.
Asunto(s)
Células Madre Hematopoyéticas , Síndromes Mielodisplásicos , Humanos , Pronóstico , Síndromes Mielodisplásicos/patología , Síndromes Mielodisplásicos/mortalidad , Síndromes Mielodisplásicos/diagnóstico , Células Madre Hematopoyéticas/patología , Células Madre Hematopoyéticas/metabolismo , Femenino , Masculino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Adulto , Mutación , Biomarcadores de Tumor , Tasa de SupervivenciaAsunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Compuestos Bicíclicos Heterocíclicos con Puentes/uso terapéutico , Hematopoyesis Clonal/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Células Madre Neoplásicas/efectos de los fármacos , Sulfonamidas/uso terapéutico , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Compuestos Bicíclicos Heterocíclicos con Puentes/efectos adversos , Humanos , Leucemia Mieloide Aguda/patología , Células Madre Neoplásicas/patología , Inducción de Remisión , Sulfonamidas/efectos adversos , Resultado del TratamientoRESUMEN
Blood myeloid cells are known to be dysregulated in coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2. It is unknown whether the innate myeloid response differs with disease severity and whether markers of innate immunity discriminate high-risk patients. Thus, we performed high-dimensional flow cytometry and single-cell RNA sequencing of COVID-19 patient peripheral blood cells and detected disappearance of non-classical CD14LowCD16High monocytes, accumulation of HLA-DRLow classical monocytes (Human Leukocyte Antigen - DR isotype), and release of massive amounts of calprotectin (S100A8/S100A9) in severe cases. Immature CD10LowCD101-CXCR4+/- neutrophils with an immunosuppressive profile accumulated in the blood and lungs, suggesting emergency myelopoiesis. Finally, we show that calprotectin plasma level and a routine flow cytometry assay detecting decreased frequencies of non-classical monocytes could discriminate patients who develop a severe form of COVID-19, suggesting a predictive value that deserves prospective evaluation.
Asunto(s)
Infecciones por Coronavirus , Coronavirus , Pandemias , Neumonía Viral , Betacoronavirus , COVID-19 , Citometría de Flujo , Humanos , Complejo de Antígeno L1 de Leucocito , Monocitos , Células Mieloides , Estudios Prospectivos , SARS-CoV-2Asunto(s)
Implantación de Mama/efectos adversos , Implantes de Mama/efectos adversos , Linfoma Anaplásico de Células Grandes/diagnóstico , Linfoma Anaplásico de Células Grandes/etiología , Anciano , Biomarcadores , Biopsia , Médula Ósea/metabolismo , Femenino , Humanos , Inmunohistoquímica , Inmunofenotipificación , Linfoma Anaplásico de Células Grandes/terapiaAsunto(s)
Gripe Humana/complicaciones , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/etiología , Antibacterianos/uso terapéutico , Antivirales/uso terapéutico , Eritroblastos/patología , Femenino , Humanos , Gripe Humana/diagnóstico , Gripe Humana/tratamiento farmacológico , Linfohistiocitosis Hemofagocítica/tratamiento farmacológico , Persona de Mediana Edad , MielografíaRESUMEN
Ten-eleven-translocation 2 (TET2) belongs to the TET protein family that catalyzes the conversion of 5-methylcytosine into 5-hydroxymethylcytosine and plays a central role in normal and malignant adult hematopoiesis. Yet the role of TET2 in human hematopoietic development remains largely unknown. Here, we show that TET2 expression is low in human embryonic stem cell (ESC) lines and increases during hematopoietic differentiation. shRNA-mediated TET2 knockdown had no effect on the pluripotency of various ESCs. However, it skewed their differentiation into neuroectoderm at the expense of endoderm and mesoderm both in vitro and in vivo. These effects were rescued by reintroducing the targeted TET2 protein. Moreover, TET2-driven differentiation was dependent on NANOG transcriptional factor. Indeed, TET2 bound to NANOG promoter and in TET2-deficient cells the methylation of the NANOG promoter correlated with a decreased in NANOG expression. The altered differentiation resulting from TET2 knockdown in ESCs led to a decrease in both the number and the cloning capacities of hematopoietic progenitors. These defects were due to an increased apoptosis and an altered gene expression profile, including abnormal expression of neuronal genes. Intriguingly, when TET2 was knockdown in hematopoietic cells, it increased hematopoietic development. In conclusion, our work suggests that TET2 is involved in different stages of human embryonic development, including induction of the mesoderm and hematopoietic differentiation.
Asunto(s)
Diferenciación Celular/fisiología , Proteínas de Unión al ADN/metabolismo , Células Madre Embrionarias/citología , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/citología , Proteínas Proto-Oncogénicas/metabolismo , Western Blotting , Línea Celular , Inmunoprecipitación de Cromatina , Dioxigenasas , Citometría de Flujo , Técnicas de Silenciamiento del Gen , Proteínas de Homeodominio/metabolismo , Humanos , Mesodermo/citología , Mesodermo/metabolismo , Proteína Homeótica Nanog , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
TET2 converts 5-methylcytosine to 5-hydroxymethylcytosine (5-hmC) in DNA and is frequently mutated in myeloid malignancies, including myeloproliferative neoplasms. Here we show that the level of 5-hmC is decreased in granulocyte DNA from myeloproliferative neoplasm patients with TET2 mutations compared with granulocyte DNA from healthy patients. Inhibition of TET2 by RNA interference decreases 5-hmC levels in both human leukemia cell lines and cord blood CD34(+) cells. These results confirm the enzymatic function of TET2 in human hematopoietic cells. Knockdown of TET2 in cord blood CD34(+) cells skews progenitor differentiation toward the granulomonocytic lineage at the expense of lymphoid and erythroid lineages. In addition, by monitoring in vitro granulomonocytic development we found a decreased granulocytic differentiation and an increase in monocytic cells. Our results indicate that TET2 disruption affects 5-hmC levels in human myeloid cells and participates in the pathogenesis of myeloid malignancies through the disturbance of myeloid differentiation.
Asunto(s)
5-Metilcitosina/metabolismo , Citosina/análogos & derivados , Metilación de ADN/genética , Proteínas de Unión al ADN/fisiología , Eritropoyesis/genética , Células Madre Hematopoyéticas/citología , Mielopoyesis/genética , Proteínas Proto-Oncogénicas/fisiología , Interferencia de ARN , ARN Interferente Pequeño/genética , Línea Celular Tumoral , Linaje de la Célula , Ensayo de Unidades Formadoras de Colonias , Citosina/biosíntesis , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/genética , Dioxigenasas , Eritropoyesis/fisiología , Sangre Fetal/citología , Vectores Genéticos/genética , Granulocitos/metabolismo , Granulocitos/patología , Humanos , Lentivirus/genética , Monocitos/metabolismo , Monocitos/patología , Mutación , Mielopoyesis/fisiología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , ARN Interferente Pequeño/administración & dosificaciónRESUMEN
Very few recurrent chromosomal abnormalities have been identified in T-cell non-Hodgkin lymphomas. These involve the TRA@/TRD@ gene at chromosome band 14q11 in up to 15% of cases. We recently reported a novel and recurrent translocation, t(14;19)(q11;q13), in peripheral T-cell lymphoma (PTCL). Fluorescence in situ hybridization analysis performed in three cases suggested an involvement of the TRA@/TRD@ locus at 14q11 and of a region telomeric to BCL3 on 19q13. We now report the molecular cloning of these translocations. Sequence analysis confirmed the involvement of the TRA@/TRD@ and indicated that the breakpoints were located mainly in the TRAJ region. On chromosome 19, our results revealed a new clustering of breakpoints outside the region involved in t(14;19)(q32;q13)-positive B-cell malignancies. Remarkably, all three breaks were located downstream or within the PVRL2 gene, in a small 10.3 kb interval, suggesting a nonrandom location of the breakpoints. For two patients, a high mRNA expression of both PVRL2 and BCL3 was found. In conclusion, we identified PVRL2 as a new recurrent partner gene of the TRA@ locus in PTCL. These results suggest that both BCL3 and PVRL2 may participate in the pathogenesis of these PTCLs, but further studies should be undertaken to investigate the precise role of these genes.