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Most of the known regulatory mechanisms that curb inflammatory gene expression target pre-transcription-initiation steps, and evidence for post-initiation regulation of inflammatory gene expression remains scarce. We found that the transcriptional repressor Hes1 suppressed production of CXCL1, a chemokine that is crucial for recruiting neutrophils. Hes1 negatively regulated neutrophil recruitment in vivo in a manner that was dependent on macrophage-produced CXCL1, and it attenuated the severity of inflammatory arthritis. Mechanistically, inhibition of Cxcl1 expression by Hes1 did not involve modification of transcription initiation. Instead, Hes1 inhibited signal-induced recruitment of the positive transcription-elongation complex P-TEFb and thereby prevented phosphorylation of RNA polymerase II at Ser2 and productive elongation. Thus, our results identify Hes1 as a homeostatic suppressor of inflammatory responses that exerts its suppressive function by regulating transcription elongation.
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Artrite/genética , Proteínas de Ciclo Celular/metabolismo , Inflamação/genética , Macrófagos/imunologia , Fatores de Transcrição HES-1/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Células Cultivadas , Quimiocina CXCL1/genética , Quimiocina CXCL1/metabolismo , Regulação da Expressão Gênica/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação/genética , Infiltração de Neutrófilos/genética , Fator B de Elongação Transcricional Positiva/genética , Fator B de Elongação Transcricional Positiva/metabolismo , RNA Polimerase II/metabolismo , Elongação da Transcrição Genética , Fatores de Transcrição HES-1/genéticaRESUMO
Wilms tumors (WTs) are histologically diverse childhood cancers with variable contributions of blastema, stroma, and epithelia. A variety of cancer genes operate in WTs, including the tripartite-motif-containing-28 gene (TRIM28). Case reports and small case series suggest that TRIM28 mutations are associated with epithelial morphology and WT predisposition. Here, we systematically investigated the prevalence of TRIM28 inactivation and predisposing mutations in a cohort of 126 WTs with >2/3 epithelial cells, spanning 20 years of biobanking in the German SIOP93-01/GPOH and SIOP2001/GPOH studies. Overall, 44.4% (56/126) cases exhibited loss of TRIM28 by immunohistochemical staining. Of these, 48 could be further analyzed molecularly, revealing TRIM28 sequence variants in each case - either homozygous (~2/3) or heterozygous with epigenetic silencing of the second allele (~1/3). The majority (80%) of the mutations resulted in premature stops and frameshifts. In addition, we detected missense mutations and small deletions predicted to destabilize the protein through interference with folding of key structural elements such as the zinc-binding clusters of the RING, B-box-2, and PHD domains or the central coiled-coil region. TRIM28-mutant tumors otherwise lacked WT-typical IGF2 alterations or driver events, except for rare TP53 progression events that occurred with expected frequency. Expression profiling identified TRIM28-mutant tumors as a homogeneous subset of epithelial WTs that mostly present with stage I disease. There was a high prevalence of perilobar nephrogenic rests, putative precursor lesions, that carried the same biallelic TRIM28 alterations in 7/7 cases tested. Importantly, 46% of the TRIM28 mutations were present in blood cells or normal kidney tissue, suggesting germline events or somatic mosaicism, partly supported by family history. Given the high prevalence of predisposing variants in TRIM28-driven WT, we suggest that immunohistochemical testing of TRIM28 be integrated into diagnostic practice as the management of WT in predisposed children differs from that with sporadic tumors. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
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Neoplasias Renais , Tumor de Wilms , Criança , Humanos , Neoplasias Renais/patologia , Bancos de Espécimes Biológicos , Tumor de Wilms/metabolismo , Rim/patologia , Mutação em Linhagem Germinativa , Suscetibilidade a Doenças/patologia , Proteína 28 com Motivo Tripartido/genéticaRESUMO
Non-invasive differentiation of paediatric kidney tumours is particularly important in the SIOP-RTSG protocols, which recommend pre-operative chemotherapy without histological confirmation. The identification of clinical and tumour-related parameters may enhance diagnostic accuracy. Age, metastases, and tumour volume (TV) were retrospectively analysed in 3306 patients enrolled in SIOP/GPOH 9, 93-01, and 2001 including Wilms tumour (WT), congenital mesoblastic nephroma (CMN), clear cell sarcoma (CCSK), malignant rhabdoid tumour of the kidney (MRTK), and renal cell carcinoma (RCC). WT was diagnosed in 2927 (88.5%) patients followed by CMN 138 (4.2%), CCSK 126 (3.8%), MRTK 58 (1.8%) and RCC 57 (1.7%). CMN, the most common localized tumour (71.6%) in patients younger than 3 months of age, was diagnosed earliest and RCC the latest (median age [months]: 0 and 154, respectively) both associated with significantly smaller TV (median TV [mL]: 67.2 and 45.0, respectively). RCC occurred in >14% of patients older than 120 months or older than 84 months with TV <100 mL. Receiver operating characteristic analyses discriminated WT from CMN, RCC and MRTK regarding age (AUC = 0.976, 0.929 and 0.791) and TV (AUC = 0.768, 0.813 and 0.622). MRTK had the highest risk of metastasis (37.9%) despite young age, whereas the risk of metastasis increased significantly with age in WT. Age and TV at diagnosis can differentiate WT from CMN and RCC. MRTK must be considered for metastatic tumours at young age. Identification of CCSK without histology remains challenging. Combined with MRI-characteristics, including diffusion-weighted imaging, and radiomics and liquid biopsies in the future, our approach allows optimization of biopsy recommendations and prevention of misdiagnosis-based neoadjuvant treatment.
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Carcinoma de Células Renais , Neoplasias Renais , Nefroma Mesoblástico , Tumor Rabdoide , Tumor de Wilms , Humanos , Criança , Lactente , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/patologia , Estudos Retrospectivos , Neoplasias Renais/patologia , Tumor de Wilms/diagnóstico , Tumor de Wilms/patologia , Nefroma Mesoblástico/congênito , Nefroma Mesoblástico/patologia , Nefroma Mesoblástico/cirurgia , Tumor Rabdoide/diagnóstico , Tumor Rabdoide/patologiaRESUMO
BACKGROUND: Among patients with nephroblastoma, those with bilateral disease are a unique population where maximising tumour control must be balanced with preserving renal parenchyma. METHODS: The SIOP 2001 protocol recommended surgery after neoadjuvant cycle(s) of Dactinomycin and Vincristine (AV) with response-adapted intensification, if needed. Adjuvant treatment was given based on the lesion with the worst histology. RESULTS: Three hundred and twenty seven patients with stage V disease were evaluable: 174 had bilateral Wilms tumour (BWT), 101 unilateral WT and contralateral nephroblastomatosis (NB) and 52 bilateral nephroblastomatosis. In these three groups, the estimated 5y-EFS was 76.1%, 84.6%, and 74.9%, respectively. AV chemotherapy alone was the successful chemotherapy for 58.7% of all the patients and 65.6% of the non-metastatic patients. Among the 174 patients with BWT, 149 (88.2%) had at least one nephron-sparing surgery. Twenty of 61 bilateral stage I patients were treated with four-week AV postoperatively achieving 94.4% 5y-EFS. At last follow-up, 87% of patients had normal renal function. CONCLUSIONS: This study demonstrates that AV without anthracyclines is sufficient to achieve NSS and good survival in the majority of patients. For patients with bilateral stage I WT and intermediate risk histology, only four weeks adjuvant AV seems to be sufficient. CLINICAL TRIAL REGISTRATION: NCT00047138.
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In this Article, author Benedikt Brors was erroneously associated with affiliation number '8' (Department of Developmental Neurobiology, St Jude Children's Research Hospital, Memphis, Tennessee, USA); the author's two other affiliations (affiliations '3' and '7', both at the German Cancer Research Center (DKFZ)) were correct. This has been corrected online.
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Pan-cancer analyses that examine commonalities and differences among various cancer types have emerged as a powerful way to obtain novel insights into cancer biology. Here we present a comprehensive analysis of genetic alterations in a pan-cancer cohort including 961 tumours from children, adolescents, and young adults, comprising 24 distinct molecular types of cancer. Using a standardized workflow, we identified marked differences in terms of mutation frequency and significantly mutated genes in comparison to previously analysed adult cancers. Genetic alterations in 149 putative cancer driver genes separate the tumours into two classes: small mutation and structural/copy-number variant (correlating with germline variants). Structural variants, hyperdiploidy, and chromothripsis are linked to TP53 mutation status and mutational signatures. Our data suggest that 7-8% of the children in this cohort carry an unambiguous predisposing germline variant and that nearly 50% of paediatric neoplasms harbour a potentially druggable event, which is highly relevant for the design of future clinical trials.
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Genoma Humano/genética , Genômica , Mutação/genética , Neoplasias/classificação , Neoplasias/genética , Adolescente , Adulto , Criança , Cromotripsia , Estudos de Coortes , Variações do Número de Cópias de DNA/genética , Diploide , Predisposição Genética para Doença/genética , Mutação em Linhagem Germinativa/genética , Humanos , Terapia de Alvo Molecular , Taxa de Mutação , Neoplasias/tratamento farmacológico , Proteína Supressora de Tumor p53/genética , Adulto JovemRESUMO
The expansion of knowledge regarding driver mutations for Wilms tumor (WT) and malignant rhabdoid tumor of the kidney (MRT) and various translocations for other pediatric renal tumors opens up new possibilities for diagnosis and treatment. In addition, there are growing data surrounding prognostic factors that can be used to stratify WT treatment to improve outcomes. Here, we review the molecular landscape of WT and other pediatric renal tumors as well as WT prognostic factors. We also review incorporation of circulating tumor DNA/liquid biopsies to leverage this molecular landscape, with potential use in the future for distinguishing renal tumors at the time of diagnosis and elucidating intratumor heterogeneity, which is not well evaluated with standard biopsies. Incorporation of liquid biopsies will require longitudinal collection of multiple biospecimens. Further preclinical research, identification and validation of biomarkers, molecular studies, and data sharing among investigators are crucial to inform therapeutic strategies that improve patient outcomes.
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Neoplasias Renais , Tumor de Wilms , Criança , Humanos , Neoplasias Renais/patologia , Tumor de Wilms/patologia , Biópsia Líquida , Biomarcadores Tumorais/genética , BiologiaRESUMO
Wilms tumor (WT) is the most common renal tumor in childhood. We and others have previously identified oncogenic driver mutations affecting the microprocessor genes DROSHA and DGCR8 that lead to altered miRNA expression patterns. In the case of DGCR8, a single recurrent hotspot mutation (E518K) was found in the RNA binding domain. To functionally assess this mutation in vitro, we generated mouse Dgcr8-KO embryonic stem cell (mESC) lines with an inducible expression of wild-type or mutant DGCR8, mirroring the hemizygous mutant expression seen in WT. RNA-seq analysis revealed significant differences of miRNA expression profiles in DGCR8-E518K compared with DGCR8-wild-type mESCs. The E518K mutation only led to a partial rescue of the reported miRNA processing defect in Dgcr8-KO, with selectively reduced expression of numerous canonical miRNAs. Nevertheless, DGCR8-E518K retained significant activity given its ability to still process many miRNAs. Subsequent to altered miRNA levels, the expression of mRNA targets was likewise changed. Functional assays showed that DGCR8-E518K cells still have a partial proliferation and differentiation defect but were able to rescue critical biological processes in embryoid body development. The stem cell program could be shut down and all three germ layers were formed. These findings suggest that the E518K mutation leads to a partial reduction of microprocessor activity and altered specificity with selective impairment only in certain developmental contexts, apparently including nephrogenesis.
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Fenômenos Biológicos , Neoplasias Renais , MicroRNAs , Proteínas de Ligação a RNA , Tumor de Wilms , Animais , Feminino , Expressão Gênica , Humanos , Neoplasias Renais/genética , Masculino , Camundongos , MicroRNAs/metabolismo , Mutação , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Ribonuclease III/genética , Tumor de Wilms/genéticaRESUMO
The undifferentiated state of muscle stem (satellite) cells (MuSCs) is maintained by the canonical Notch pathway. Although three bHLH transcriptional factors, Hey1, HeyL and Hes1, are considered to be potential effectors of the Notch pathway exerting anti-myogenic effects, neither HeyL nor Hes1 inhibits myogenic differentiation of myogenic cell lines. Furthermore, whether these factors work redundantly or cooperatively is unknown. Here, we showed cell-autonomous functions of Hey1 and HeyL in MuSCs using conditional and genetic null mice. Analysis of cultured MuSCs revealed anti-myogenic activity of both HeyL and Hes1. We found that HeyL forms heterodimeric complexes with Hes1 in living cells. Moreover, our ChIP-seq experiments demonstrated that, compared with HeyL alone, the HeyL-Hes1 heterodimer binds with high affinity to specific sites in the chromatin, including the binding sites of Hey1. Finally, analyses of myogenin promoter activity showed that HeyL and Hes1 act synergistically to suppress myogenic differentiation. Collectively, these results suggest that HeyL and Hey1 function redundantly in MuSCs, and that HeyL requires Hes1 for effective DNA binding and biological activity.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação da Expressão Gênica , Células Satélites de Músculo Esquelético/citologia , Fatores de Transcrição HES-1/metabolismo , Alelos , Animais , Sítios de Ligação , Separação Celular , Cromatina/química , DNA/química , Citometria de Fluxo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Ligação Proteica , Multimerização Proteica , Estrutura Secundária de Proteína , Receptores Notch/metabolismo , Transdução de SinaisRESUMO
In children, renal cell carcinoma (RCC) is rare. This study is the first report of pediatric patients with RCC registered by the International Society of Pediatric Oncology-Renal Tumor Study Group (SIOP-RTSG). Pediatric patients with histologically confirmed RCC, registered in SIOP 93-01, 2001 and UK-IMPORT databases, were included. Event-free survival (EFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Between 1993 and 2019, 122 pediatric patients with RCC were registered. Available detailed data (n = 111) revealed 56 localized, 30 regionally advanced, 25 metastatic and no bilateral cases. Histological classification according to World Health Organization 2004, including immunohistochemical and molecular testing for transcription factor E3 (TFE3) and/or EB (TFEB) translocation, was available for 65/122 patients. In this group, the most common histological subtypes were translocation type RCC (MiT-RCC) (36/64, 56.3%), papillary type (19/64, 29.7%) and clear cell type (4/64, 6.3%). One histological subtype was not reported. In the remaining 57 patients, translocation testing could not be performed, or TFE-cytogenetics and/or immunohistochemistry results were missing. In this group, the most common RCC histological subtypes were papillary type (21/47, 44.7%) and clear cell type (11/47, 23.4%). Ten histological subtypes were not reported. Estimated 5-year (5y) EFS and 5y OS of the total group was 70.5% (95% CI = 61.7%-80.6%) and 84.5% (95% CI = 77.5%-92.2%), respectively. Estimated 5y OS for localized, regionally advanced, and metastatic disease was 96.8%, 92.3%, and 45.6%, respectively. In conclusion, the registered pediatric patients with RCC showed a reasonable outcome. Survival was substantially lower for patients with metastatic disease. This descriptive study stresses the importance of full, prospective registration including TFE-testing.
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Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/mortalidade , Adolescente , Carcinoma de Células Renais/classificação , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Feminino , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Neoplasias Renais/classificação , Neoplasias Renais/genética , Neoplasias Renais/metabolismo , Masculino , Prognóstico , Estudos Prospectivos , Análise de Sobrevida , Translocação Genética , Reino UnidoRESUMO
BACKGROUND: Wilms tumor (WT) is the most common renal tumor in childhood. Among others, MYCN copy number gain and MYCN P44L and MAX R60Q mutations have been identified in WT. MYCN encodes a transcription factor that requires dimerization with MAX to activate transcription of numerous target genes. MYCN gain has been associated with adverse prognosis in different childhood tumors including WT. The MYCN P44L and MAX R60Q mutations, located in either the transactivating or basic helix-loop-helix domain, respectively, are predicted to be damaging by different pathogenicity prediction tools, but the functional consequences remain to be characterized. METHODS: We screened a large cohort of unselected WTs for MYCN and MAX alterations. Wild-type and mutant protein function were characterized biochemically, and we analyzed the N-MYC protein interactome by mass spectrometric analysis of N-MYC containing protein complexes. RESULTS: Mutation screening revealed mutation frequencies of 3% for MYCN P44L and 0.9% for MAX R60Q that are associated with a higher risk of relapse. Biochemical characterization identified a reduced transcriptional activation potential for MAX R60Q, while the MYCN P44L mutation did not change activation potential or protein stability. The protein interactome of N-MYC-P44L was likewise not altered as shown by mass spectrometric analyses of purified N-MYC complexes. Nevertheless, we could identify a number of novel N-MYC partner proteins, e.g. PEG10, YEATS2, FOXK1, CBLL1 and MCRS1, whose expression is correlated with MYCN in WT samples and several of these are known for their own oncogenic potential. CONCLUSIONS: The strongly elevated risk of relapse associated with mutant MYCN and MAX or elevated MYCN expression corroborates their role in WT oncogenesis. Together with the newly identified co-expressed interactors they expand the range of potential biomarkers for WT stratification and targeting, especially for high-risk WT.
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Wilms tumor (WT) is the most common kidney cancer in childhood. Mutations in the microprocessor genes DROSHA and DGCR8 have been identified as putative oncogenic drivers, indicating a critical role of aberrant miRNA processing in WT formation. To characterize the in vivo role of DROSHA mutations during kidney development and their oncogenic potential, we analyzed mouse lines with either a targeted deletion of Drosha or an inducible expression of human DROSHA carrying a tumor-specific E1147K mutation that acts in a dominant negative manner. Both types of mutation induce striking changes in miRNA patterns. Six2-cre mediated deletion of Drosha in nephron progenitors led to perinatal lethality with apoptotic loss of progenitor cells and early termination of nephrogenesis. Mosaic deletions via Wt1-creERT2 resulted in a milder phenotype with viable offspring that developed proteinuria after 2-4 weeks, but no evidence of tumor formation. Activation of the DROSHA-E1147K transgene via Six2-cre, on the other hand, induced a more severe phenotype with apoptosis of progenitor cells, proteinuria and glomerular sclerosis. The severely growth retarded mice died within the first 2 months of life, confirming the predicted dominant-negative effect of DROSHA-E1147K in vivo. While our data underscores the importance of a viable self-renewing progenitor pool for kidney development, there was no evidence of tumor formation through impaired DROSHA function. This suggests that either additional alterations in mitogenic or antiapoptotic pathways are needed for malignant transformation, or premature loss of a susceptible target cell population and early lethality prevent WT formation.
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Neoplasias Renais/genética , Rim/embriologia , Organogênese/genética , Ribonuclease III/genética , Tumor de Wilms/genética , Animais , Apoptose/genética , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Rim/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , MicroRNAs/metabolismo , Mutação , Células-Tronco/fisiologiaRESUMO
Wilms tumors are the most common type of pediatric kidney tumors. While the overall prognosis for patients is favorable, especially tumors that exhibit a blastemal subtype after preoperative chemotherapy have a poor prognosis. For an improved risk assessment and therapy stratification, it is essential to identify the driving factors that are distinctive for this aggressive subtype. In our study, we compared gene expression profiles of 33 tumor biopsies (17 blastemal and 16 other tumors) after neoadjuvant chemotherapy. The analysis of this dataset using the Regulator Gene Association Enrichment algorithm successfully identified several biomarkers and associated molecular mechanisms that distinguish between blastemal and nonblastemal Wilms tumors. Specifically, regulators involved in embryonic development and epigenetic processes like chromatin remodeling and histone modification play an essential role in blastemal tumors. In this context, we especially identified TCF3 as the central regulatory element. Furthermore, the comparison of ChIP-Seq data of Wilms tumor cell cultures from a blastemal mouse xenograft and a stromal tumor provided further evidence that the chromatin states of blastemal cells share characteristics with embryonic stem cells that are not present in the stromal tumor cell line. These stem-cell like characteristics could potentially add to the increased malignancy and chemoresistance of the blastemal subtype. Along with TCF3, we detected several additional biomarkers that are distinctive for blastemal Wilms tumors after neoadjuvant chemotherapy and that may provide leads for new therapeutic regimens.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais/patologia , Células-Tronco Neoplásicas/patologia , Tumor de Wilms/patologia , Adolescente , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Biópsia , Criança , Pré-Escolar , Conjuntos de Dados como Assunto , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Rim/citologia , Rim/patologia , Rim/cirurgia , Neoplasias Renais/genética , Neoplasias Renais/terapia , Masculino , Camundongos , Terapia Neoadjuvante/métodos , Nefrectomia , Cultura Primária de Células , Células Tumorais Cultivadas , Tumor de Wilms/genética , Tumor de Wilms/terapiaRESUMO
Two percent of patients with Wilms tumors have a positive family history. In many of these cases the genetic cause remains unresolved. By applying germline exome sequencing in two families with two affected individuals with Wilms tumors, we identified truncating mutations in TRIM28. Subsequent mutational screening of germline and tumor DNA of 269 children affected by Wilms tumor was performed, and revealed seven additional individuals with germline truncating mutations, and one individual with a somatic truncating mutation in TRIM28. TRIM28 encodes a complex scaffold protein involved in many different processes, including gene silencing, DNA repair and maintenance of genomic integrity. Expression studies on mRNA and protein level showed reduction of TRIM28, confirming a loss-of-function effect of the mutations identified. The tumors showed an epithelial-type histology that stained negative for TRIM28 by immunohistochemistry. The tumors were bilateral in six patients, and 10/11 tumors are accompanied by perilobar nephrogenic rests. Exome sequencing on eight tumor DNA samples from six individuals showed loss-of-heterozygosity (LOH) of the TRIM28-locus by mitotic recombination in seven tumors, suggesting that TRIM28 functions as a tumor suppressor gene in Wilms tumor development. Additionally, the tumors showed very few mutations in known Wilms tumor driver genes, suggesting that loss of TRIM28 is the main driver of tumorigenesis. In conclusion, we identified heterozygous germline truncating mutations in TRIM28 in 11 children with mainly epithelial-type Wilms tumors, which become homozygous in tumor tissue. These data establish TRIM28 as a novel Wilms tumor predisposition gene, acting as a tumor suppressor gene by LOH.
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Haploinsuficiência/genética , Proteína 28 com Motivo Tripartido/genética , Tumor de Wilms/genética , Carcinogênese/genética , Pré-Escolar , DNA de Neoplasias/genética , Feminino , Genes do Tumor de Wilms/fisiologia , Predisposição Genética para Doença/genética , Genótipo , Mutação em Linhagem Germinativa/genética , Heterozigoto , Humanos , Lactente , Neoplasias Renais/genética , Mutação com Perda de Função/genética , Perda de Heterozigosidade/genética , Masculino , Sequenciamento do Exoma/métodosRESUMO
Motivation: Transcriptional regulators play a major role in most biological processes. Alterations in their activities are associated with a variety of diseases and in particular with tumor development and progression. Hence, it is important to assess the effects of deregulated regulators on pathological processes. Results: Here, we present REGulator-Gene Association Enrichment (REGGAE), a novel method for the identification of key transcriptional regulators that have a significant effect on the expression of a given set of genes, e.g. genes that are differentially expressed between two sample groups. REGGAE uses a Kolmogorov-Smirnov-like test statistic that implicitly combines associations between regulators and their target genes with an enrichment approach to prioritize the influence of transcriptional regulators. We evaluated our method in two different application scenarios, which demonstrate that REGGAE is well suited for uncovering the influence of transcriptional regulators and is a valuable tool for the elucidation of complex regulatory mechanisms. Availability and implementation: REGGAE is freely available at https://regulatortrail.bioinf.uni-sb.de. Supplementary information: Supplementary data are available at Bioinformatics online.
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Regulação da Expressão Gênica , Neoplasias/genética , Transcrição Gênica , Feminino , Humanos , Probabilidade , SoftwareRESUMO
Undifferentiated solid tumors with small blue round cell histology and expression of CD99 mostly resemble Ewing sarcoma. However, they also may include other tumors such as mesenchymal chondrosarcoma, synovial sarcoma, or small cell osteosarcoma. Definitive classification usually requires detection of entity-specific mutations. While this approach identifies the majority of Ewing sarcomas, a subset of lesions remains unclassified and, therefore, has been termed "Ewing-like sarcomas" or small blue round cell tumors not otherwise specified. We developed an approach for further characterization of small blue round cell tumors not otherwise specified using an array-based DNA-methylation profiling approach. Data were analyzed by unsupervised clustering and t-distributed stochastic neighbor embedding analysis and compared with a reference methylation data set of 460 well-characterized prototypical sarcomas encompassing 18 subtypes. Verification was performed by additional FISH analyses, RNA sequencing from formalin-fixed paraffin-embedded material or immunohistochemical marker analyses. In a cohort of more than 1,000 tumors assumed to represent Ewing sarcomas, 30 failed to exhibit the typical EWS translocation. These tumors were subjected to methylation profiling and could be assigned to Ewing sarcoma in 14 (47%), to small blue round cell tumors with CIC alteration in 6 (20%), to small blue round cell tumors with BCOR alteration in 4 (13%), to synovial sarcoma and to malignant rhabdoid tumor in 2 cases each. One single case each was allotted to mesenchymal chondrosarcoma and adamantinoma. 12/14 tumors classified as Ewing sarcoma could be verified by demonstrating either a canonical EWS translocation evading initial testing, by identifying rare breakpoints or fusion partners. The methylation-based assignment of the remaining small blue round cell tumors not otherwise specified also could be verified by entity-specific molecular alterations in 13/16 cases. In conclusion, array-based DNA-methylation analysis of undifferentiated tumors with small blue round cell histology is a powerful tool for precisely classifying this diagnostically challenging tumor group.
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Metilação de DNA/genética , Perfilação da Expressão Gênica/métodos , Sarcoma de Células Pequenas/classificação , Sarcoma de Células Pequenas/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Patients with DICER1 predisposition syndrome have an increased risk to develop pleuropulmonary blastoma, cystic nephroma, embryonal rhabdomyosarcoma, and several other rare tumor entities. In this study, we identified 22 primary intracranial sarcomas, including 18 in pediatric patients, with a distinct methylation signature detected by array-based DNA-methylation profiling. In addition, two uterine rhabdomyosarcomas sharing identical features were identified. Gene panel sequencing of the 22 intracranial sarcomas revealed the almost unifying feature of DICER1 hotspot mutations (21/22; 95%) and a high frequency of co-occurring TP53 mutations (12/22; 55%). In addition, 17/22 (77%) sarcomas exhibited alterations in the mitogen-activated protein kinase pathway, most frequently affecting the mutational hotspots of KRAS (8/22; 36%) and mutations or deletions of NF1 (7/22; 32%), followed by mutations of FGFR4 (2/22; 9%), NRAS (2/22; 9%), and amplification of EGFR (1/22; 5%). A germline DICER1 mutation was detected in two of five cases with constitutional DNA available. Notably, none of the patients showed evidence of a cancer-related syndrome at the time of diagnosis. In contrast to the genetic findings, the morphological features of these tumors were less distinctive, although rhabdomyoblasts or rhabdomyoblast-like cells could retrospectively be detected in all cases. The identified combination of genetic events indicates a relationship between the intracranial tumors analyzed and DICER1 predisposition syndrome-associated sarcomas such as embryonal rhabdomyosarcoma or the recently described group of anaplastic sarcomas of the kidney. However, the intracranial tumors in our series were initially interpreted to represent various tumor types, but rhabdomyosarcoma was not among the typical differential diagnoses considered. Given the rarity of intracranial sarcomas, this molecularly clearly defined group comprises a considerable fraction thereof. We therefore propose the designation "spindle cell sarcoma with rhabdomyosarcoma-like features, DICER1 mutant" for this intriguing group.
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RNA Helicases DEAD-box/genética , Predisposição Genética para Doença/genética , Mutação/genética , Rabdomiossarcoma Embrionário/genética , Ribonuclease III/genética , Sarcoma/genética , Metilação de DNA/genética , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Estudos Retrospectivos , Rabdomiossarcoma Embrionário/patologia , Sarcoma/patologiaRESUMO
BACKGROUND: Congenital mesoblastic nephroma (MN) is a rare pediatric renal tumor representing approximately 5% of all pediatric renal tumors. Three different types of MN are distinguished histologically: classical, cellular, and mixed. A frequent genetic alteration is the translocation t(12;15) resulting in a fusion of the ETV6 gene on 12p13 and the NTRK3 gene on 15p15 that occurs almost exclusively in cellular MN. The aim of this study was to determine translocation status of a large cohort of MN with respect to tumor subtype and outcome. PROCEDURE: In total, clinical data from 111 patients were available. Sixty-seven tumors were classical MN (51%), 29 cellular MN (31%), and 15 were mixed MN (18%). From these 111 cases, 79 were analyzed by FISH and RT-PCR. RESULTS: All classical and mixed MN were translocation negative. Seventeen out of 29 (58%) cellular MN harbored the ETV6-NTRK3 translocation. Five-year relapse-free survival (RFS) and overall survival (OS) were 93.2% and 96.8% for the complete cohort. All seven relapses occurred in translocation negative tumors. Five-year RFS was significantly inferior for cellular and mixed MN compared to classic MN (89%, 80%, and 98%), whereas 5-year OS was similar (93%, 96%, and 98%). Within the group of cellular MN, patients having translocation-positive tumors had a significantly superior RFS (5-year RFS: 100% vs. 73%). CONCLUSION: The majority of cellular MNs harbor the ETV6-NTKR3 gene fusion, whereas all classic- and mixed-type MNs were translocation negative. Within the cellular subgroup, patients having translocation-positive tumors had a significantly superior RFS.
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Cromossomos Humanos Par 12 , Cromossomos Humanos Par 15 , Nefroma Mesoblástico , Proteínas de Fusão Oncogênica , Translocação Genética , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 12/metabolismo , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 15/metabolismo , Intervalo Livre de Doença , Feminino , Humanos , Hibridização in Situ Fluorescente , Masculino , Nefroma Mesoblástico/genética , Nefroma Mesoblástico/metabolismo , Nefroma Mesoblástico/mortalidade , Nefroma Mesoblástico/patologia , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de SobrevidaRESUMO
MOTIVATION: Gene set analysis has revolutionized the interpretation of high-throughput transcriptomic data. Nowadays, with comprehensive studies that measure multiple -omics from the same sample, powerful tools for the integrative analysis of multi-omics datasets are required. RESULTS: Here, we present GeneTrail2, a web service allowing the integrated analysis of transcriptomic, miRNomic, genomic and proteomic datasets. It offers multiple statistical tests, a large number of predefined reference sets, as well as a comprehensive collection of biological categories and enables direct comparisons between the computed results. We used GeneTrail2 to explore pathogenic mechanisms of Wilms tumors. We not only succeeded in revealing signaling cascades that may contribute to the malignancy of blastemal subtype tumors but also identified potential biomarkers for nephroblastoma with adverse prognosis. The presented use-case demonstrates that GeneTrail2 is well equipped for the integrative analysis of comprehensive -omics data and may help to shed light on complex pathogenic mechanisms in cancer and other diseases. AVAILABILITY AND IMPLEMENTATION: GeneTrail2 can be freely accessed under https://genetrail2.bioinf.uni-sb.de CONTACT: : dstoeckel@bioinf.uni-sb.de SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Assuntos
Genômica , Proteômica , Transcriptoma , Genoma , Humanos , NeoplasiasRESUMO
Toll-like receptor (TLR) responses are regulated to avoid toxicity and achieve coordinated responses appropriate for the cell environment. We found that Notch and TLR pathways cooperated to activate canonical Notch target genes, including transcriptional repressors Hes1 and Hey1, and to increase production of canonical TLR-induced cytokines TNF, IL-6, and IL-12. Cooperation by these pathways to increase target gene expression was mediated by the Notch-pathway component and transcription factor RBP-J, which also contributed to lethality after endotoxin injection. TLR- and Notch-induced Hes1 and Hey1 attenuated IL-6 and IL-12 production. This Hes1- and Hey1-mediated feedback inhibitory loop was abrogated by interferon-gamma (IFN-gamma), which blocked TLR-induced activation of canonical Notch target genes by inhibiting Notch2 signaling and downstream transcription. These findings identify new immune functions for RBP-J, Hes, and Hey proteins and provide insights into mechanisms by which Notch, TLR, and IFN-gamma signals are integrated to modulate specific effector functions in macrophages.