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1.
Blood ; 142(1): 90-105, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37146239

RESUMO

RNA-binding proteins (RBPs) form a large and diverse class of factors, many members of which are overexpressed in hematologic malignancies. RBPs participate in various processes of messenger RNA (mRNA) metabolism and prevent harmful DNA:RNA hybrids or R-loops. Here, we report that PIWIL4, a germ stem cell-associated RBP belonging to the RNase H-like superfamily, is overexpressed in patients with acute myeloid leukemia (AML) and is essential for leukemic stem cell function and AML growth, but dispensable for healthy human hematopoietic stem cells. In AML cells, PIWIL4 binds to a small number of known piwi-interacting RNA. Instead, it largely interacts with mRNA annotated to protein-coding genic regions and enhancers that are enriched for genes associated with cancer and human myeloid progenitor gene signatures. PIWIL4 depletion in AML cells downregulates the human myeloid progenitor signature and leukemia stem cell (LSC)-associated genes and upregulates DNA damage signaling. We demonstrate that PIWIL4 is an R-loop resolving enzyme that prevents R-loop accumulation on a subset of AML and LSC-associated genes and maintains their expression. It also prevents DNA damage, replication stress, and activation of the ATR pathway in AML cells. PIWIL4 depletion potentiates sensitivity to pharmacological inhibition of the ATR pathway and creates a pharmacologically actionable dependency in AML cells.


Assuntos
Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/patologia , Células-Tronco Hematopoéticas/metabolismo , Proliferação de Células , Genômica , RNA Mensageiro/metabolismo , Células-Tronco Neoplásicas/patologia
2.
Nucleic Acids Res ; 47(2): 570-581, 2019 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-30517751

RESUMO

RNA-binding proteins (RBPs) control and coordinate each stage in the life cycle of RNAs. Although in vivo binding sites of RBPs can now be determined genome-wide, most studies typically focused on individual RBPs. Here, we examined a large compendium of 114 high-quality transcriptome-wide in vivo RBP-RNA cross-linking interaction datasets generated by the same protocol in the same cell line and representing 64 distinct RBPs. Comparative analysis of categories of target RNA binding preference, sequence preference, and transcript region specificity was performed, and identified potential posttranscriptional regulatory modules, i.e. specific combinations of RBPs that bind to specific sets of RNAs and targeted regions. These regulatory modules represented functionally related proteins and exhibited distinct differences in RNA metabolism, expression variance, as well as subcellular localization. This integrative investigation of experimental RBP-RNA interaction evidence and RBP regulatory function in a human cell line will be a valuable resource for understanding the complexity of post-transcriptional regulation.


Assuntos
Regulação da Expressão Gênica , RNA/metabolismo , Ribonucleoproteínas/metabolismo , Sequência de Bases , Sítios de Ligação , Células HEK293 , Humanos , RNA/química , Ribonucleoproteínas/classificação
3.
Gut ; 69(1): 133-145, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31409605

RESUMO

OBJECTIVE: The Fragile X mental retardation (FMR) syndrome is a frequently inherited intellectual disability caused by decreased or absent expression of the FMR protein (FMRP). Lack of FMRP is associated with neuronal degradation and cognitive dysfunction but its role outside the central nervous system is insufficiently studied. Here, we identify a role of FMRP in liver disease. DESIGN: Mice lacking Fmr1 gene expression were used to study the role of FMRP during tumour necrosis factor (TNF)-induced liver damage in disease model systems. Liver damage and mechanistic studies were performed using real-time PCR, Western Blot, staining of tissue sections and clinical chemistry. RESULTS: Fmr1null mice exhibited increased liver damage during virus-mediated hepatitis following infection with the lymphocytic choriomeningitis virus. Exposure to TNF resulted in severe liver damage due to increased hepatocyte cell death. Consistently, we found increased caspase-8 and caspase-3 activation following TNF stimulation. Furthermore, we demonstrate FMRP to be critically important for regulating key molecules in TNF receptor 1 (TNFR1)-dependent apoptosis and necroptosis including CYLD, c-FLIPS and JNK, which contribute to prolonged RIPK1 expression. Accordingly, the RIPK1 inhibitor Necrostatin-1s could reduce liver cell death and alleviate liver damage in Fmr1null mice following TNF exposure. Consistently, FMRP-deficient mice developed increased pathology during acute cholestasis following bile duct ligation, which coincided with increased hepatic expression of RIPK1, RIPK3 and phosphorylation of MLKL. CONCLUSIONS: We show that FMRP plays a central role in the inhibition of TNF-mediated cell death during infection and liver disease.


Assuntos
Proteína do X Frágil da Deficiência Intelectual/fisiologia , Hepatite Viral Animal/imunologia , Fator de Necrose Tumoral alfa/imunologia , Animais , Infecções por Arenaviridae/imunologia , Infecções por Arenaviridae/patologia , Linfócitos T CD8-Positivos/imunologia , Morte Celular/efeitos dos fármacos , Morte Celular/imunologia , Morte Celular/fisiologia , Células Cultivadas , Colestase/imunologia , Colestase/metabolismo , Colestase/patologia , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Hepatite Viral Animal/patologia , Hepatite Viral Animal/prevenção & controle , Hepatócitos/patologia , Imidazóis/farmacologia , Imidazóis/uso terapêutico , Indóis/farmacologia , Indóis/uso terapêutico , Vírus da Coriomeningite Linfocítica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Serina-Treonina Quinases de Interação com Receptores/antagonistas & inibidores , Proteína Serina-Treonina Quinases de Interação com Receptores/fisiologia
4.
Int J Mol Sci ; 21(10)2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32408494

RESUMO

Acute leukemias are genetic diseases caused by translocations or mutations, which dysregulate hematopoiesis towards malignant transformation. However, the molecular mode of action is highly versatile and ranges from direct transcriptional to post-transcriptional control, which includes RNA-binding proteins (RBPs) as crucial regulators of cell fate. RBPs coordinate RNA dynamics, including subcellular localization, translational efficiency and metabolism, by binding to their target messenger RNAs (mRNAs), thereby controlling the expression of the encoded proteins. In view of the growing interest in these regulators, this review summarizes recent research regarding the most influential RBPs relevant in acute leukemias in particular. The reported RBPs, either dysregulated or as components of fusion proteins, are described with respect to their functional domains, the pathways they affect, and clinical aspects associated with their dysregulation or altered functions.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Doença Aguda , Animais , Humanos , Leucemia/metabolismo , Conformação de Ácido Nucleico , Ligação Proteica , Domínios Proteicos , RNA Mensageiro/química , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo
5.
Int J Mol Sci ; 21(12)2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32585856

RESUMO

Medulloblastomas arise from undifferentiated precursor cells in the cerebellum and account for about 20% of all solid brain tumors during childhood; standard therapies include radiation and chemotherapy, which oftentimes come with severe impairment of the cognitive development of the young patients. Here, we show that the posttranscriptional regulator Y-box binding protein 1 (YBX1), a DNA- and RNA-binding protein, acts as an oncogene in medulloblastomas by regulating cellular survival and apoptosis. We observed different cellular responses upon YBX1 knockdown in several medulloblastoma cell lines, with significantly altered transcription and subsequent apoptosis rates. Mechanistically, PAR-CLIP for YBX1 and integration with RNA-Seq data uncovered direct posttranscriptional control of the heterochromatin-associated gene CBX5; upon YBX1 knockdown and subsequent CBX5 mRNA instability, heterochromatin-regulated genes involved in inflammatory response, apoptosis and death receptor signaling were de-repressed. Thus, YBX1 acts as an oncogene in medulloblastoma through indirect transcriptional regulation of inflammatory genes regulating apoptosis and represents a promising novel therapeutic target in this tumor entity.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Regulação Neoplásica da Expressão Gênica , Heterocromatina/genética , Inflamação/patologia , Meduloblastoma/patologia , RNA Mensageiro/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/imunologia , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Homólogo 5 da Proteína Cromobox , Proteínas Cromossômicas não Histona/genética , Humanos , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Meduloblastoma/genética , Meduloblastoma/imunologia , Meduloblastoma/metabolismo , RNA Mensageiro/genética , Células Tumorais Cultivadas , Proteína 1 de Ligação a Y-Box/genética
6.
J Biol Chem ; 293(40): 15359-15369, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30126842

RESUMO

The RNA-binding protein Musashi 2 (MSI2) has emerged as an important regulator in cancer initiation, progression, and drug resistance. Translocations and deregulation of the MSI2 gene are diagnostic of certain cancers, including chronic myeloid leukemia (CML) with translocation t(7;17), acute myeloid leukemia (AML) with translocation t(10;17), and some cases of B-precursor acute lymphoblastic leukemia (pB-ALL). To better understand the function of MSI2 in leukemia, the mRNA targets that are bound and regulated by MSI2 and their MSI2-binding motifs need to be identified. To this end, using photoactivatable ribonucleoside cross-linking and immunoprecipitation (PAR-CLIP) and the multiple EM for motif elicitation (MEME) analysis tool, here we identified MSI2's mRNA targets and the consensus RNA-recognition element (RRE) motif recognized by MSI2 (UUAG). Of note, MSI2 knockdown altered the expression of several genes with roles in eukaryotic initiation factor 2 (eIF2), hepatocyte growth factor (HGF), and epidermal growth factor (EGF) signaling pathways. We also show that MSI2 regulates classic interleukin-6 (IL-6) signaling by promoting the degradation of the mRNA of IL-6 signal transducer (IL6ST or GP130), which, in turn, affected the phosphorylation statuses of signal transducer and activator of transcription 3 (STAT3) and the mitogen-activated protein kinase ERK. In summary, we have identified multiple MSI2-regulated mRNAs and provided evidence that MSI2 controls IL6ST activity that control oncogenic signaling networks. Our findings may help inform strategies for unraveling the role of MSI2 in leukemia to pave the way for the development of targeted therapies.


Assuntos
Receptor gp130 de Citocina/genética , Interleucina-6/genética , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Transcriptoma , Sequência de Bases , Sítios de Ligação , Receptor gp130 de Citocina/metabolismo , Fator de Crescimento Epidérmico/genética , Fator de Crescimento Epidérmico/metabolismo , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Células HEK293 , Fator de Crescimento de Hepatócito/genética , Fator de Crescimento de Hepatócito/metabolismo , Humanos , Imunoprecipitação , Interleucina-6/metabolismo , Leucemia/genética , Leucemia/metabolismo , Leucemia/patologia , Luz , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Modelos Biológicos , Ligação Proteica , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
7.
J Virol ; 92(3)2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29142134

RESUMO

Innate immune activation is essential to mount an effective antiviral response and to prime adaptive immunity. Although a crucial role of CD169+ cells during vesicular stomatitis virus (VSV) infections is increasingly recognized, factors regulating CD169+ cells during viral infections remain unclear. Here, we show that tumor necrosis factor is produced by CD11b+ Ly6C+ Ly6G+ cells following infection with VSV. The absence of TNF or TNF receptor 1 (TNFR1) resulted in reduced numbers of CD169+ cells and in reduced type I interferon (IFN-I) production during VSV infection, with a severe disease outcome. Specifically, TNF triggered RelA translocation into the nuclei of CD169+ cells; this translocation was inhibited when the paracaspase MALT-1 was absent. Consequently, MALT1 deficiency resulted in reduced VSV replication, defective innate immune activation, and development of severe disease. These findings indicate that TNF mediates the maintenance of CD169+ cells and innate and adaptive immune activation during VSV infection.IMPORTANCE Over the last decade, strategically placed CD169+ metallophilic macrophages in the marginal zone of the murine spleen and lymph nodes (LN) have been shown to play a very important role in host defense against viral pathogens. CD169+ macrophages have been shown to activate innate and adaptive immunity via "enforced virus replication," a controlled amplification of virus particles. However, the factors regulating the CD169+ macrophages remain to be studied. In this paper, we show that after vesicular stomatitis virus infection, phagocytes produce tumor necrosis factor (TNF), which signals via TNFR1, and promote enforced virus replication in CD169+ macrophages. Consequently, lack of TNF or TNFR1 resulted in defective immune activation and VSV clearance.


Assuntos
Interferon Tipo I/imunologia , Macrófagos/imunologia , Fator de Necrose Tumoral alfa/imunologia , Estomatite Vesicular/imunologia , Imunidade Adaptativa , Animais , Imunidade Inata , Macrófagos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Translocação 1 do Linfoma de Tecido Linfoide Associado à Mucosa/genética , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico , Fator de Transcrição RelA/metabolismo , Vesiculovirus/fisiologia , Replicação Viral
8.
Genet Med ; 21(12): 2706-2712, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31204389

RESUMO

PURPOSE: Biallelic pathogenic variants in the mismatch repair (MMR) genes cause a recessive childhood cancer predisposition syndrome known as constitutional mismatch repair deficiency (CMMRD). Family members with a heterozygous MMR variant have Lynch syndrome. We aimed at estimating cancer risk in these heterozygous carriers as a novel approach to avoid complicated statistical methods to correct for ascertainment bias. METHODS: Cumulative colorectal cancer incidence was estimated in a cohort of PMS2- and MSH6-associated families, ascertained by the CMMRD phenotype of the index, by using mutation probabilities based on kinship coefficients as analytical weights in a proportional hazard regression on the cause-specific hazards. Confidence intervals (CIs) were obtained by bootstrapping at the family level. RESULTS: The estimated cumulative colorectal cancer risk at age 70 years for heterozygous PMS2 variant carriers was 8.7% (95% CI 4.3-12.7%) for both sexes combined, and 9.9% (95% CI 4.9-15.3%) for men and 5.9% (95% CI 1.6-11.1%) for women separately. For heterozygous MSH6 variant carriers these estimates are 11.8% (95% CI 4.5-22.7%) for both sexes combined, 10.0% (95% CI 1.83-24.5%) for men and 11.7% (95% CI 2.10-26.5%) for women. CONCLUSION: Our findings are consistent with previous reports that used more complex statistical methods to correct for ascertainment bias. These results underline the need for MMR gene-specific surveillance protocols for Lynch syndrome.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais/etiologia , Medição de Risco/métodos , Adulto , Idoso , Estudos de Coortes , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Reparo de Erro de Pareamento de DNA , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Endonuclease PMS2 de Reparo de Erro de Pareamento/genética , Endonuclease PMS2 de Reparo de Erro de Pareamento/metabolismo , Mutação , Fatores de Risco
9.
Haematologica ; 104(1): 35-46, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30093397

RESUMO

The homeobox gene HLXB9 encodes for the transcription factor HB9, which is essential for pancreatic as well as motor neuronal development. Beside its physiological expression pattern, aberrant HB9 expression has been observed in several neoplasias. Especially in infant translocation t(7;12) acute myeloid leukemia, aberrant HB9 expression is the only known molecular hallmark and is assumed to be a key factor in leukemic transformation. However, so far, only poor functional data exist addressing the oncogenic potential of HB9 or its influence on hematopoiesis. We investigated the influence of HB9 on cell proliferation and cell cycle in vitro, as well as on hematopoietic stem cell differentiation in vivo using murine and human model systems. In vitro, HB9 expression led to premature senescence in human HT1080 and murine NIH3T3 cells, providing for the first time evidence for an oncogenic potential of HB9. Onset of senescence was characterized by induction of the p53-p21 tumor suppressor network, resulting in growth arrest, accompanied by morphological transformation and expression of senescence-associated ß-galactosidase. In vivo, HB9-transduced primary murine hematopoietic stem and progenitor cells underwent a profound differentiation arrest and accumulated at the megakaryocyte/erythrocyte progenitor stage. In line, gene expression analyses revealed de novo expression of erythropoiesis-related genes in human CD34+hematopoietic stem and progenitor cells upon HB9 expression. In summary, the novel findings of HB9-dependent premature senescence and myeloid-biased perturbed hematopoietic differentiation, for the first time shed light on the oncogenic properties of HB9 in translocation t(7;12) acute myeloid leukemia.


Assuntos
Ciclo Celular , Diferenciação Celular , Senescência Celular , Regulação Leucêmica da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Homeodomínio/biossíntese , Leucemia Mieloide Aguda/metabolismo , Proteínas de Neoplasias/biossíntese , Fatores de Transcrição/biossíntese , Animais , Eritropoese/genética , Células-Tronco Hematopoéticas/patologia , Proteínas de Homeodomínio/genética , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Camundongos , Células NIH 3T3 , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , Translocação Genética
10.
Eur J Pediatr ; 178(12): 1893-1902, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31624947

RESUMO

Life-limiting conditions in children in specialized pediatric palliative care (PPC) are manifold. The "Together for Short Lives" (TfSL) association established four disease categories, which represent the most common illness trajectories. Better understanding the palliative care needs and symptoms of children within these TfSL groups will result in improved anticipation of clinical problems and tailored care. During this retrospective single-center cohort study, 198 children, adolescents, and young adults (CAYAs) were in PPC. Mean age at referral was 8.7 years (range 0.0-25.0), mean duration of care 355 days (range 1-2754). One hundred six (53.5%) CAYAs died during the study period. Sixty-five (32.8%) CAYAs were assigned to TfSL-1, 13 (6.6%) to TfSL-2, 49 (24.7%) to TfSL-3, and 71 (35.9%) to TfSL-4. Home visits were conducted on average every 9.6 days in TfSL-1, 18.9 days in TfSL-2, 31.7 days in TfSL-3, and 31.8 days in TfSL-4 (p value < 0.01).Conclusions: Intensity of palliative care significantly differed between the TfSL groups. Neurological and gastrointestinal symptoms were most prominent across all TfSL groups. Symptom cluster analysis showed distinct clusters in TfSL-1 (cluster 1, fatigue/lack of appetite/nausea/somnolence; cluster 2, dyspnea/fear/myoclonus/seizures/spasticity) and TfSL-3/4 (cluster 1, spasticity; cluster 2, all other symptoms).What is Known:• The four TfSL (together for short lives) groups represent the four most common illness trajectories of pediatric palliative care patients.• Better understanding the palliative care needs and symptoms of children within these four TfSL groups will result in improved anticipation of clinical problems and tailored care.What is New:• In our study, TfSL-1 represented the largest individual group of patients, also requiring the most intensive care (defined by the number of visits per days of care).• Symptom cluster analysis revealed distinct symptom clusters in TfSL-1 and TfSL-3/4, which can be used to anticipate clinically common challenges in these patients.


Assuntos
Cuidados Paliativos , Assistência Terminal , Adolescente , Atitude Frente a Morte , Criança , Pré-Escolar , Feminino , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Síndrome , Adulto Jovem
11.
Br J Haematol ; 180(1): 82-89, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29193007

RESUMO

Relapse remains the major cause of treatment failure in children with high-risk acute lymphoblastic leukaemia (ALL) undergoing allogeneic haematopoietic stem-cell transplantation (allo-SCT). Prognosis is considered dismal but data on risk factors and outcome are lacking from prospective studies. We analysed 242 children with recurrence of ALL after first allo-SCT enrolled in the Berlin-Frankfurt-Munster (BFM) ALL-SCT-BFM 2003 and ALL-SCT-BFM international 2007 studies. Median time from allo-SCT to relapse was 7·7 months; median follow-up from relapse after allo-SCT until last follow-up was 3·4 years. The 3-year event-free survival (EFS) was 15% and overall survival (OS) was 20%. The main cause of death was disease progression or relapse (86·5%). The majority of children (48%) received salvage therapy without second allo-SCT, 26% of the children underwent a second allo-SCT and 25% received palliative treatment only. In multivariate analyses, age, site of relapse, time to relapse and type of salvage therapy were identified as significant prognostic factors for OS and EFS, whereas factors associated with first SCT were not statistically significant. Combined approaches incorporating novel immunotherapeutic treatment options and second allo-SCT hold promise to improve outcome in children with post allo-SCT relapse.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Prognóstico , Modelos de Riscos Proporcionais , Recidiva , Indução de Remissão , Retratamento , Terapia de Salvação , Análise de Sobrevida , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
12.
Proc Natl Acad Sci U S A ; 112(38): E5261-70, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26351698

RESUMO

Despite the established role of the transcription factor MYC in cancer, little is known about the impact of a new class of transcriptional regulators, the long noncoding RNAs (lncRNAs), on MYC ability to influence the cellular transcriptome. Here, we have intersected RNA-sequencing data from two MYC-inducible cell lines and a cohort of 91 B-cell lymphomas with or without genetic variants resulting in MYC overexpression. We identified 13 lncRNAs differentially expressed in IG-MYC-positive Burkitt lymphoma and regulated in the same direction by MYC in the model cell lines. Among them, we focused on a lncRNA that we named MYC-induced long noncoding RNA (MINCR), showing a strong correlation with MYC expression in MYC-positive lymphomas. To understand its cellular role, we performed RNAi and found that MINCR knockdown is associated with an impairment in cell cycle progression. Differential gene expression analysis after RNAi showed a significant enrichment of cell cycle genes among the genes down-regulated after MINCR knockdown. Interestingly, these genes are enriched in MYC binding sites in their promoters, suggesting that MINCR acts as a modulator of the MYC transcriptional program. Accordingly, MINCR knockdown was associated with a reduction in MYC binding to the promoters of selected cell cycle genes. Finally, we show that down-regulation of Aurora kinases A and B and chromatin licensing and DNA replication factor 1 may explain the reduction in cellular proliferation observed on MINCR knockdown. We, therefore, suggest that MINCR is a newly identified player in the MYC transcriptional network able to control the expression of cell cycle genes.


Assuntos
Linfoma de Burkitt/metabolismo , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Linfoma de Células B/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , RNA Longo não Codificante/metabolismo , Sequência de Bases , Sítios de Ligação , Ciclo Celular , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Cromatina/metabolismo , Perfilação da Expressão Gênica , Humanos , Hibridização in Situ Fluorescente , Dados de Sequência Molecular , Neoplasias/metabolismo , Regiões Promotoras Genéticas , RNA Interferente Pequeno/metabolismo , Homologia de Sequência do Ácido Nucleico
13.
Genes Chromosomes Cancer ; 56(2): 159-167, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27717083

RESUMO

For reasons not yet understood, nearly all infants with acute lymphoblastic leukemia (ALL) are diagnosed with the B-cell type, with T-ALL in infancy representing a very rare exception. Clinical and molecular knowledge about infant T-ALL is still nearly completely lacking and it is also still unclear whether it represents a distinct disease compared to childhood T-ALL. To address this, we performed exome sequencing of three infant cases, which enabled the detection of mutations in NOTCH2, NOTCH3, PTEN, and KRAS. When analyzing the transcriptomes and miRNomes of the three infant and an additional six childhood T-ALL samples, we found 760 differentially expressed mRNAs and 58 differentially expressed miRNAs between these two cohorts. Correlation analysis for differentially expressed miRNA-mRNA target pairs revealed 47 miRNA-mRNA pairs, with many of them previously described to be aberrantly expressed in leukemia and cancer. Pathway analysis revealed differentially expressed pathways and upstream regulators related to the immune system or cancerogenesis such as the ERK5 pathway, which was activated in infant T-ALL. In summary, there are distinct molecular features in infant compared to childhood T-ALL on a transcriptomic and epigenetic level, which potentially have an impact on the development and course of the disease. © 2016 Wiley Periodicals, Inc.


Assuntos
Biomarcadores Tumorais/genética , Epigênese Genética/genética , Perfilação da Expressão Gênica , Regulação Leucêmica da Expressão Gênica , MicroRNAs/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Transcriptoma/genética , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico
14.
Eur J Pediatr ; 176(10): 1319-1327, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28808789

RESUMO

The number of children without a diagnosis in pediatric palliative home care and the process of decision-making in these children are widely unknown. The study was conducted as single-center retrospective cohort study. Between January 2013 and September 2016, 198 children and young adults were cared for; 27 (13.6%) of these were without a clear diagnosis at the start of pediatric palliative home care. A definite diagnosis was ultimately achieved in three children. Median age was 7 years (0-25), duration of care 569 days (2-2638), and number of home visits 7.5 (2-46). Most patients are still alive (19; 70.4%). Median number of drugs administered was eight (range 2-19); antiepileptics were given most frequently. Despite the lack of a clear diagnosis (and thus prognosis), 13 (48.1%) parents faced with their critically ill and clinically deteriorating children decided in favor of a DNAR order. Comparing this with 15 brain-injured children, signs, symptoms, and supportive needs were similar in both groups. CONCLUSION: Children without a clear diagnosis are relatively common in pediatric palliative care and have-like all other patients-the right to receive optimized and symptom-adapted palliative care. Parents are less likely to choose treatment limitation for children who lack a definitive diagnosis. What is Known: • A clear diagnosis is usually considered important for best-practice pediatric palliative care (PPC) including advanced care planning (ACP). • Timely initiation of pediatric palliative care (PPC) is highly recommended in children with life-limiting conditions. What is New: • SWAN (syndrome without a name) children show similar signs and symptoms (mostly neurological) and have similar supportive needs as brain-injured children. • Defining treatment limitations in advance care planning is more difficult for parents of SWAN compared to brain-injured children.


Assuntos
Diagnóstico Tardio/estatística & dados numéricos , Cuidados Paliativos , Adolescente , Planejamento Antecipado de Cuidados/ética , Criança , Pré-Escolar , Tomada de Decisão Clínica , Tomada de Decisões , Diagnóstico Tardio/ética , Diagnóstico Tardio/psicologia , Feminino , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino , Cuidados Paliativos/ética , Cuidados Paliativos/métodos , Cuidados Paliativos/psicologia , Cuidados Paliativos/estatística & dados numéricos , Pais/psicologia , Relações Profissional-Família , Estudos Retrospectivos , Síndrome , Assistência Terminal/ética , Assistência Terminal/métodos , Assistência Terminal/psicologia , Suspensão de Tratamento/ética , Adulto Jovem
15.
Haematologica ; 101(11): 1380-1389, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27390358

RESUMO

MicroRNA are well-established players in post-transcriptional gene regulation. However, information on the effects of microRNA deregulation mainly relies on bioinformatic prediction of potential targets, whereas proof of the direct physical microRNA/target messenger RNA interaction is mostly lacking. Within the International Cancer Genome Consortium Project "Determining Molecular Mechanisms in Malignant Lymphoma by Sequencing", we performed miRnome sequencing from 16 Burkitt lymphomas, 19 diffuse large B-cell lymphomas, and 21 follicular lymphomas. Twenty-two miRNA separated Burkitt lymphomas from diffuse large B-cell lymphomas/follicular lymphomas, of which 13 have shown regulation by MYC. Moreover, we found expression of three hitherto unreported microRNA. Additionally, we detected recurrent mutations of hsa-miR-142 in diffuse large B-cell lymphomas and follicular lymphomas, and editing of the hsa-miR-376 cluster, providing evidence for microRNA editing in lymphomagenesis. To interrogate the direct physical interactions of microRNA with messenger RNA, we performed Argonaute-2 photoactivatable ribonucleoside-enhanced cross-linking and immunoprecipitation experiments. MicroRNA directly targeted 208 messsenger RNA in the Burkitt lymphomas and 328 messenger RNA in the non-Burkitt lymphoma models. This integrative analysis discovered several regulatory pathways of relevance in lymphomagenesis including Ras, PI3K-Akt and MAPK signaling pathways, also recurrently deregulated in lymphomas by mutations. Our dataset reveals that messenger RNA deregulation through microRNA is a highly relevant mechanism in lymphomagenesis.


Assuntos
Linfoma de Células B/genética , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Análise de Sequência de RNA/métodos , Adolescente , Linfoma de Burkitt/genética , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Centro Germinativo , Humanos , Lactente , Recém-Nascido , Linfoma Folicular/genética , Linfoma Difuso de Grandes Células B/genética , Masculino , MicroRNAs/genética , Mutação , Edição de RNA
16.
Genes Chromosomes Cancer ; 53(11): 911-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25044415

RESUMO

Burkitt lymphoma (BL) is the most frequent B-cell lymphoma in childhood. Genetically, it is characterized by the presence of an IG-MYC translocation which is supposed to be an initiating but not sufficient event in Burkitt lymphomagenesis. In a recent whole-genome sequencing study of four cases, we showed that the gene encoding the ras homolog family member A (RHOA) is recurrently mutated in pediatric BL. Here, we analyzed RHOA by Sanger sequencing in a cohort of 101 pediatric B-cell lymphoma patients treated according to Non-Hodgkin's Lymphoma Berlin-Frankfurt-Münster (NHL-BFM) study protocols. Among the 78 BLs in this series, an additional five had RHOA mutations resulting in a total incidence of 7/82 (8.5%) with c.14G>A (p.R5Q) being present in three cases. Modeling the mutational effect suggests that most of them inactivate the RHOA protein. Thus, deregulation of RHOA by mutation is a recurrent event in Burkitt lymphomagenesis in children.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfoma de Burkitt/genética , Linfoma de Células B/genética , Proteína rhoA de Ligação ao GTP/genética , Adolescente , Asparaginase/uso terapêutico , Linfoma de Burkitt/patologia , Linfoma de Burkitt/terapia , Criança , Pré-Escolar , Estudos de Coortes , Daunorrubicina/uso terapêutico , Feminino , Humanos , Linfoma de Células B/patologia , Linfoma de Células B/terapia , Masculino , Mutação , Pediatria , Prednisona/uso terapêutico , Vincristina/uso terapêutico , Proteína rhoA de Ligação ao GTP/metabolismo
17.
Sci Rep ; 14(1): 8569, 2024 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-38609482

RESUMO

65 million people worldwide are estimated to suffer from long-term symptoms after their SARS-CoV-2 infection (Long COVID). However, there is still little information about the early recovery among those who initially developed Long COVID, i.e. had symptoms 4-12 weeks after infection but no symptoms after 12 weeks. We aimed to identify associated factors with this early recovery. We used data from SARS-CoV-2-infected individuals from the DigiHero study. Participants provided information about their SARS-CoV-2 infections and symptoms at the time of infection, 4-12 weeks, and more than 12 weeks post-infection. We performed multivariable logistic regression to identify factors associated with early recovery from Long COVID and principal component analysis (PCA) to identify groups among symptoms. 5098 participants reported symptoms at 4-12 weeks after their SARS-CoV-2 infection, of which 2441 (48%) reported no symptoms after 12 weeks. Men, younger participants, individuals with mild course of acute infection, individuals infected with the Omicron variant, and individuals who did not seek medical care in the 4-12 week period after infection had a higher chance of early recovery. In the PCA, we identified four distinct symptom groups. Our results indicate differential risk of continuing symptoms among individuals who developed Long COVID. The identified risk factors are similar to those for the development of Long COVID, so people with these characteristics are at higher risk not only for developing Long COVID, but also for longer persistence of symptoms. Those who sought medical help were also more likely to have persistent symptoms.


Assuntos
COVID-19 , Síndrome de COVID-19 Pós-Aguda , Masculino , Humanos , SARS-CoV-2 , Análise de Componente Principal
18.
NPJ Vaccines ; 9(1): 23, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38316833

RESUMO

The rapid development of safe and effective vaccines helped to prevent severe disease courses after SARS-CoV-2 infection and to mitigate the progression of the COVID-19 pandemic. While there is evidence that vaccination may reduce the risk of developing post-COVID-19 conditions (PCC), this effect may depend on the viral variant. Therapeutic effects of post-infection vaccination have been discussed but the data for individuals with PCC remains inconclusive. In addition, extremely rare side effects after SARS-CoV-2 vaccination may resemble the heterogeneous PCC phenotype. Here, we analyze the plasma levels of 25 cytokines and SARS-CoV-2 directed antibodies in 540 individuals with or without PCC relative to one or two mRNA-based COVID-19 vaccinations as well as in 20 uninfected individuals one month after their initial mRNA-based COVID-19 vaccination. While none of the SARS-CoV-2 naïve individuals reported any persisting sequelae or exhibited PCC-like dysregulation of plasma cytokines, we detected lower levels of IL-1ß and IL-18 in patients with ongoing PCC who received one or two vaccinations at a median of six months after infection as compared to unvaccinated PCC patients. This reduction correlated with less frequent reporting of persisting gastrointestinal symptoms. These data suggest that post-infection vaccination in patients with PCC might be beneficial in a subgroup of individuals displaying gastrointestinal symptoms.

19.
Adv Exp Med Biol ; 774: 1-20, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23377965

RESUMO

Mature microRNAs (miRNAs) are single-stranded RNA molecules of 20-23-nucleotide (nt) length that control gene expression in many cellular processes. These molecules typically reduce the translation and stability of mRNAs, including those of genes that mediate processes in tumorigenesis, such as inflammation, cell cycle regulation, stress response, differentiation, apoptosis, and invasion. miRNA targeting is initiated through specific base-pairing interactions between the 5' end ("seed" region) of the miRNA and sites within coding and untranslated regions (UTRs) of mRNAs; target sites in the 3' UTR lead to more effective mRNA destabilization. Since miRNAs frequently target hundreds of mRNAs, miRNA regulatory pathways are complex. To provide a critical overview of miRNA dysregulation in cancer, we first discuss the methods currently available for studying the role of miRNAs in cancer and then review miRNA genomic organization, biogenesis, and mechanism of target recognition, examining how these processes are altered in tumorigenesis. Given the critical role miRNAs play in tumorigenesis processes and their disease specific expression, they hold potential as therapeutic targets and novel biomarkers.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/genética , Sequência de Bases , Perfilação da Expressão Gênica , Genômica , Humanos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
20.
BJPsych Open ; 9(3): e66, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37057843

RESUMO

BACKGROUND: In the connected world, although societies are not directly involved in a military conflict, they are exposed to media reports of violence. AIMS: We assessed the effects of such exposures on mental health in Germany during the military conflict in Ukraine. METHOD: We used the German population-based cohort for digital health research, DigiHero, launching a survey on the eighth day of the Russo-Ukrainian war. Of the 27 509 cohort participants from the general population, 19 444 (70.7%) responded within 17 days. We measured mental health and fear of the impact of war compared with other fears (natural disasters or health-related). RESULTS: In a subsample of 4441 participants assessed twice, anxiety in the population (measured by the Generalised Anxiety Disorder-7 screener) was higher in the first weeks of war than during the strongest COVID-19 restrictions. Anxiety was elevated across the whole age spectrum, and the mean was above the cut-off for mild anxiety. Over 95% of participants expressed various degrees of fear of the impact of war, whereas the percentage for other investigated fears was 0.47-0.82. A one-point difference in the fear of the impact of war was associated with a 2.5 point (95% CI 2.42-2.58) increase in anxiety (11.9% of the maximum anxiety score). For emotional distress, the increase was 0.67 points (0.66-0.68) (16.75% of the maximum score). CONCLUSIONS: The population in Germany reacted to the Russo-Ukrainian war with substantial distress, exceeding reactions during the strongest restrictions in the COVID-19 pandemic. Fear of the impact of war was associated with worse mental health.

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