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1.
Mol Ther ; 32(4): 1125-1143, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38311851

RESUMO

The CTNNB1 gene, encoding ß-catenin, is frequently mutated in hepatocellular carcinoma (HCC, ∼30%) and in hepatoblastoma (HB, >80%), in which DLK1/DIO3 locus induction is correlated with CTNNB1 mutations. Here, we aim to decipher how sustained ß-catenin activation regulates DLK1/DIO3 locus expression and the role this locus plays in HB and HCC development in mouse models deleted for Apc (ApcΔhep) or Ctnnb1-exon 3 (ß-cateninΔExon3) and in human CTNNB1-mutated hepatic cancer cells. We identified an enhancer site bound by TCF-4/ß-catenin complexes in an open conformation upon sustained ß-catenin activation (DLK1-Wnt responsive element [WRE]) and increasing DLK1/DIO3 locus transcription in ß-catenin-mutated human HB and mouse models. DLK1-WRE editing by CRISPR-Cas9 approach impaired DLK1/DIO3 locus expression and slowed tumor growth in subcutaneous CTNNB1-mutated tumor cell grafts, ApcΔhep HB and ß-cateninΔExon3 HCC. Tumor growth inhibition resulted either from increased FADD expression and subsequent caspase-3 cleavage in the first case or from decreased expression of cell cycle actors regulated by FoxM1 in the others. Therefore, the DLK1/DIO3 locus is an essential determinant of FoxM1-dependent cell proliferation during ß-catenin-driven liver tumorigenesis. Targeting the DLK1-WRE enhancer to silence the DLK1/DIO3 locus might thus represent an interesting therapeutic strategy to restrict tumor growth in primary liver cancers with CTNNB1 mutations.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Cateninas/genética , Cateninas/metabolismo , Proliferação de Células/genética , Neoplasias Hepáticas/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Regulação para Cima
2.
J Transl Med ; 22(1): 337, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589873

RESUMO

BACKGROUND: The mesenchymal subtype of colorectal cancer (CRC), associated with poor prognosis, is characterized by abundant expression of the cellular prion protein PrPC, which represents a candidate therapeutic target. How PrPC is induced in CRC remains elusive. This study aims to elucidate the signaling pathways governing PrPC expression and to shed light on the gene regulatory networks linked to PrPC. METHODS: We performed in silico analyses on diverse datasets of in vitro, ex vivo and in vivo models of mouse CRC and patient cohorts. We mined ChIPseq studies and performed promoter analysis. CRC cell lines were manipulated through genetic and pharmacological approaches. We created mice combining conditional inactivation of Apc in intestinal epithelial cells and overexpression of the human prion protein gene PRNP. Bio-informatic analyses were carried out in two randomized control trials totalizing over 3000 CRC patients. RESULTS: In silico analyses combined with cell-based assays identified the Wnt-ß-catenin and glucocorticoid pathways as upstream regulators of PRNP expression, with subtle differences between mouse and human. We uncover multiple feedback loops between PrPC and these two pathways, which translate into an aggravation of CRC pathogenesis in mouse. In stage III CRC patients, the signature defined by PRNP-CTNNB1-NR3C1, encoding PrPC, ß-catenin and the glucocorticoid receptor respectively, is overrepresented in the poor-prognosis, mesenchymal subtype and associates with reduced time to recurrence. CONCLUSIONS: An unleashed PrPC-dependent vicious circle is pathognomonic of poor prognosis, mesenchymal CRC. Patients from this aggressive subtype of CRC may benefit from therapies targeting the PRNP-CTNNB1-NR3C1 axis.


Assuntos
Neoplasias do Colo , Neoplasias Colorretais , Humanos , Camundongos , Animais , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , beta Catenina/metabolismo , Glucocorticoides , Neoplasias do Colo/genética , Neoplasias Colorretais/genética , Fenótipo , Prognóstico , Via de Sinalização Wnt , Regulação Neoplásica da Expressão Gênica , Linhagem Celular Tumoral
3.
J Hepatol ; 77(2): 424-435, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35257829

RESUMO

BACKGROUND & AIMS: One-third of hepatocellular carcinomas (HCCs) harbor mutations activating the ß-catenin pathway, predominantly via mutations in the CTNNB1 gene itself. Mouse models of Apc loss-of-function are widely used to mimic ß-catenin-dependent tumorigenesis. Given the low prevalence of APC mutations in human HCCs, we aimed to generate liver tumors through CTNNB1 exon 3 deletion (ßcatΔex3). We then compared ßcatΔex3 liver tumors with liver tumors generated via frameshift in exon 15 of Apc (Apcfs-ex15). METHODS: We used hepatocyte-specific and inducible mouse models generated through either a Cre-Lox or a CRISPR/Cas9 approach using adeno-associated virus vectors. Tumors generated by the Cre-Lox models were phenotypically analyzed using immunohistochemistry and were selected for transcriptomic analysis by RNA-sequencing (RNAseq). Mouse RNAseq data were compared to human RNAseq data (8 normal tissues, 48 HCCs, 9 hepatoblastomas) in an integrative analysis. Tumors generated via CRISPR were analyzed using DNA sequencing and immuno-histochemistry. RESULTS: Mice with CTNNB1 exon 3 deletion in hepatocytes developed liver tumors indistinguishable from Apcfs-ex15 liver tumors. Both Apcfs-ex15 and ßcatΔex3 mouse models induced growth of phenotypically distinct tumors (differentiated or undifferentiated). Integrative analysis of human and mouse tumors showed that differentiated mouse tumors cluster with well-differentiated human CTNNB1-mutated tumors. Conversely, undifferentiated mouse tumors cluster with human mesenchymal hepatoblastomas and harbor activated YAP signaling. CONCLUSION: Apcfs-ex15 and ßcatΔex3 mouse models both induce growth of tumors that are transcriptionally similar to either well-differentiated and ß-catenin-activated human HCCs or mesenchymal hepatoblastomas. LAY SUMMARY: New and easy-to-use transgenic mouse models of primary liver cancers have been generated, with mutations in the gene encoding beta-catenin, which are frequent in both adult and pediatric primary liver cancers. The mice develop both types of cancer, constituting a strong preclinical model.


Assuntos
Carcinoma Hepatocelular , Hepatoblastoma , Neoplasias Hepáticas , beta Catenina , Animais , Carcinoma Hepatocelular/patologia , Hepatoblastoma/metabolismo , Hepatócitos/metabolismo , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Transgênicos , Mutação , beta Catenina/genética
4.
J Hepatol ; 74(6): 1386-1397, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33484773

RESUMO

BACKGROUND & AIMS: The NKG2D system is a potent immunosurveillance mechanism in cancer, wherein the activating NK cell receptor (NKG2D) on immune cells recognises its cognate ligands on tumour cells. Herein, we evaluated the expression of NKG2D ligands in hepatocellular carcinoma (HCC), in both humans and mice, taking the genomic features of HCC tumours into account. METHODS: The expression of NKG2D ligands (MICA, MICB, ULBP1 and ULBP2) was analysed in large human HCC datasets by Fluidigm TaqMan and RNA-seq methods, and in 2 mouse models (mRNA and protein levels) reproducing the features of both major groups of human tumours. RESULTS: We provide compelling evidence that expression of the MICA and MICB ligands in human HCC is associated with tumour aggressiveness and poor patient outcome. We also found that the expression of ULBP1 and ULBP2 was associated with poor patient outcome, and was downregulated in CTNNB1-mutated HCCs displaying low levels of inflammation and associated with a better prognosis. We also found an inverse correlation between ULBP1/2 expression levels and the expression of ß-catenin target genes in patients with HCC, suggesting a role for ß-catenin signalling in inhibiting expression. We showed in HCC mouse models that ß-catenin signalling downregulated the expression of Rae-1 NKG2D ligands, orthologs of ULBPs, through TCF4 binding. CONCLUSIONS: We demonstrate that the expression of NKG2D ligands is associated with aggressive liver tumorigenesis and that the downregulation of these ligands by ß-catenin signalling may account for the less aggressive phenotype of CTNNB1-mutated HCC tumours. LAY SUMMARY: The NKG2D system is a potent immunosurveillance mechanism in cancer. However, its role in hepatocellular carcinoma development has not been widely investigated. Herein, we should that the expression of NKG2D ligands by tumour cells is associated with a more aggressive tumour subtype.


Assuntos
Carcinoma Hepatocelular/metabolismo , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hepáticas/metabolismo , Transdução de Sinais/genética , beta Catenina/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Estudos de Coortes , Modelos Animais de Doenças , Feminino , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
5.
Gastroenterology ; 157(3): 807-822, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31194980

RESUMO

BACKGROUND & AIMS: In one-third of hepatocellular carcinomas (HCCs), cancer cells have mutations that activate ß-catenin pathway. These cells have alterations in glutamine, bile, and lipid metabolism. We investigated whether positron emission tomography (PET) imaging allows identification of altered metabolic pathways that might be targeted therapeutically. METHODS: We studied mice with activation of ß-catenin in liver (Apcko-liv mice) and male C57Bl/6 mice given injections of diethylnitrosamine, which each develop HCCs. Mice were fed a conventional or a methionine- and choline-deficient diet or a choline-deficient (CD) diet. Choline uptake and metabolism in HCCs were analyzed by micro-PET imaging of mice; livers were collected and analyzed by histologic, metabolomic, messenger RNA quantification, and RNA-sequencing analyses. Fifty-two patients with HCC underwent PET imaging with 18F-fluorodeoxyglucose, followed by 18F-fluorocholine tracer metabolites. Human HCC specimens were analyzed by immunohistochemistry, quantitative polymerase chain reaction, and DNA sequencing. We used hepatocytes and mouse tumor explants for studies of incorporation of radiolabeled choline into phospholipids and its contribution to DNA methylation. We analyzed HCC progression in mice fed a CD diet. RESULTS: Livers and tumors from Apcko-liv mice had increased uptake of dietary choline, which contributes to phospholipid formation and DNA methylation in hepatocytes. In patients and in mice, HCCs with activated ß-catenin were positive in 18F-fluorocholine PET, but not 18F-fluorodeoxyglucose PET, and they overexpressed the choline transporter organic cation transporter 3. The HCC cells from Apcko-liv mice incorporated radiolabeled methyl groups of choline into phospholipids and DNA. In Apcko-liv mice, the methionine- and choline-deficient diet reduced proliferation and DNA hypermethylation of hepatocytes and HCC cells, and the CD diet reduced long-term progression of tumors. CONCLUSIONS: In mice and humans, HCCs with mutations that activate ß-catenin are characterized by increased uptake of a fluorocholine tracer, but not 18F-fluorodeoxyglucose, revealed by PET. The increased uptake of choline by HCCs promotes phospholipid formation, DNA hypermethylation, and hepatocyte proliferation. In mice, the CD diet reverses these effects and promotes regression of HCCs that overexpress ß-catenin.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/genética , Mutação , Tomografia por Emissão de Pósitrons , beta Catenina/genética , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Proliferação de Células , Colina/administração & dosagem , Colina/análogos & derivados , Deficiência de Colina/complicações , Metilação de DNA , Dietilnitrosamina , Modelos Animais de Doenças , Genes APC , Predisposição Genética para Doença , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Masculino , Metionina/deficiência , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Fosfolipídeos/metabolismo , Valor Preditivo dos Testes , Compostos Radiofarmacêuticos/administração & dosagem , beta Catenina/metabolismo
7.
Gut ; 68(2): 322-334, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29650531

RESUMO

OBJECTIVES: CTNNB1-mutated hepatocellular carcinomas (HCCs) constitute a major part of human HCC and are largely inaccessible to target therapy. Yet, little is known about the metabolic reprogramming induced by ß-catenin oncogenic activation in the liver. We aimed to decipher such reprogramming and assess whether it may represent a new avenue for targeted therapy of CTNNB1-mutated HCC. DESIGN: We used mice with hepatocyte-specific oncogenic activation of ß-catenin to evaluate metabolic reprogramming using metabolic fluxes on tumourous explants and primary hepatocytes. We assess the role of Pparα in knock-out mice and analysed the consequences of fatty acid oxidation (FAO) using etomoxir. We explored the expression of the FAO pathway in an annotated human HCC dataset. RESULTS: ß-catenin-activated HCC were not glycolytic but intensively oxidised fatty acids. We found that Pparα is a ß-catenin target involved in FAO metabolic reprograming. Deletion of Pparα was sufficient to block the initiation and progression of ß-catenin-dependent HCC development. FAO was also enriched in human CTNNB1-mutated HCC, under the control of the transcription factor PPARα. CONCLUSIONS: FAO induced by ß-catenin oncogenic activation in the liver is the driving force of the ß-catenin-induced HCC. Inhibiting FAO by genetic and pharmacological approaches blocks HCC development, showing that inhibition of FAO is a suitable therapeutic approach for CTNNB1-mutated HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Ácidos Graxos/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , beta Catenina/metabolismo , Animais , Compostos de Epóxi/farmacologia , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Knockout , Mutação , Oxirredução , PPAR alfa/fisiologia , beta Catenina/genética
8.
Liver Int ; 39(4): 727-739, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30721564

RESUMO

BACKGROUND & AIMS: Loss of hepatocyte nuclear factor-4α (HNF4α), a critical factor driving liver development and differentiation, is frequently associated with hepatocellular carcinoma (HCC). Our recent data revealed that HNF4α level was decreased in mouse and human HCCs with activated ß-catenin signalling. In addition, increasing HNF4α level by miR-34a inhibition slowed tumour progression of ß-catenin-activated HCC in mice. METHODS: We generated a Hnf4aflox/flox/ Apcflox/flox /TTR-CreERT2 (Hnf4a/Apc∆Hep ) mouse line and evaluated the impact of Hnf4a disruption on HCC development and liver homoeostasis. RESULTS: There was no significant impact of Hnf4a disruption on tumour onset and progression in Apc∆Hep model. However, we observed an unexpected phenotype in 28% of Hnf4a∆Hep mice maintained in a conventional animal facility, which presented disorganized portal triads, characterized by stenosis of the portal vein and increased number and size of hepatic arteries and bile ducts. These abnormal portal structures resemble the human idiopathic non-cirrhotic portal hypertension syndrome. We correlated the presence of portal remodelling with a higher expression of protein and mRNA levels of TGFß and BMP7, a key regulator of the TGFß-dependent endothelial-to-mesenchymal transition. CONCLUSION: These data demonstrate that HNF4α does not play a major role during ß-catenin-driven HCC, thus revealing that the tumour suppressor role of HNF4α is far more complex and dependent probably on its temporal expression and tumour context. However, HNF4α loss in adult hepatocytes could induce abnormal portal structures resembling the human idiopathic non-cirrhotic portal hypertension syndrome, which may result from endothelial- and epithelial-to-mesenchymal transitions.


Assuntos
Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas/genética , beta Catenina/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Proteína Morfogenética Óssea 7/metabolismo , Carcinogênese , Diferenciação Celular , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Fator 4 Nuclear de Hepatócito/genética , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Camundongos , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
9.
Gut ; 65(6): 1024-34, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-25792709

RESUMO

OBJECTIVE: Hepatocellular carcinoma (HCC) is the most prevalent primary tumour of the liver. About a third of these tumours presents activating mutations of the ß-catenin gene. The molecular pathogenesis of HCC has been elucidated, but mortality remains high, and new therapeutic approaches, including treatments based on microRNAs, are required. We aimed to identify candidate microRNAs, regulated by ß-catenin, potentially involved in liver tumorigenesis. DESIGN: We used a mouse model, in which ß-catenin signalling was overactivated exclusively in the liver by the tamoxifen-inducible and Cre-Lox-mediated inactivation of the Apc gene. This model develops tumours with properties similar to human HCC. RESULTS: We found that miR-34a was regulated by ß-catenin, and significantly induced by the overactivation of ß-catenin signalling in mouse tumours and in patients with HCC. An inhibitor of miR-34a (locked nucleic acid, LNA-34a) exerted antiproliferative activity in primary cultures of hepatocyte. This inhibition of proliferation was associated with a decrease in cyclin D1 levels, orchestrated principally by HNF-4α, a target of miR-34a considered to act as a tumour suppressor in the liver. In vivo, LNA-34a approximately halved progression rates for tumours displaying ß-catenin activation together with an activation of caspases 2 and 3. CONCLUSIONS: This work demonstrates the key oncogenic role of miR-34a in liver tumours with ß-catenin gene mutations. We suggest that patients diagnosed with HCC with ß-catenin mutations could be treated with an inhibitor of miR-34a. The potential value of this strategy lies in the modulation of the tumour suppressor HNF-4α, which targets cyclin D1, and the induction of a proapoptotic programme.


Assuntos
Ciclina D1/genética , Neoplasias Hepáticas Experimentais/genética , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Mutação , beta Catenina/genética , Animais , Carcinoma Hepatocelular/terapia , Humanos , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas Experimentais/terapia , Camundongos
10.
Hepatology ; 59(6): 2344-57, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24214913

RESUMO

UNLABELLED: ß-catenin signaling can be both a physiological and oncogenic pathway in the liver. It controls compartmentalized gene expression, allowing the liver to ensure its essential metabolic function. It is activated by mutations in 20%-40% of hepatocellular carcinomas (HCCs) with specific metabolic features. We decipher the molecular determinants of ß-catenin-dependent zonal transcription using mice with ß-catenin-activated or -inactivated hepatocytes, characterizing in vivo their chromatin occupancy by T-cell factor (Tcf)-4 and ß-catenin, transcriptome, and metabolome. We find that Tcf-4 DNA bindings depend on ß-catenin. Tcf-4/ß-catenin binds Wnt-responsive elements preferentially around ß-catenin-induced genes. In contrast, genes repressed by ß-catenin bind Tcf-4 on hepatocyte nuclear factor 4 (Hnf-4)-responsive elements. ß-Catenin, Tcf-4, and Hnf-4α interact, dictating ß-catenin transcription, which is antagonistic to that elicited by Hnf-4α. Finally, we find the drug/bile metabolism pathway to be the one most heavily targeted by ß-catenin, partly through xenobiotic nuclear receptors. CONCLUSIONS: ß-catenin patterns the zonal liver together with Tcf-4, Hnf-4α, and xenobiotic nuclear receptors. This network represses lipid metabolism and exacerbates glutamine, drug, and bile metabolism, mirroring HCCs with ß-catenin mutational activation.


Assuntos
Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas/etiologia , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , beta Catenina/metabolismo , Animais , Cromatina/metabolismo , Redes Reguladoras de Genes , Humanos , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Knockout , Receptor Cross-Talk , beta Catenina/genética
12.
Methods Mol Biol ; 2769: 167-187, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315397

RESUMO

In recent years, important efforts have been made to understand how the expression of a specific gene repertoire correlates with chromatin accessibility, histone mark deposition, as well as with chromatin looping establishing connectivity with regulatory regions. The emergence of new techniques for genome-wide analyses and their progressive optimization to work on low amounts of material allows the scientific community to obtain an integrated view of transcriptional landscapes in physiology and disease. Here, we describe our own experience aiming at correlating the TCF-4/ß-catenin cistrome during liver tumorigenesis with chromatin remodeling, histone mark modifications, and long-distance DNA looping.


Assuntos
Cromatina , Neoplasias Hepáticas , Animais , Camundongos , Cromatina/genética , Estudo de Associação Genômica Ampla , Cromossomos , DNA , Neoplasias Hepáticas/genética
13.
Med Sci (Paris) ; 29(10): 861-7, 2013 Oct.
Artigo em Francês | MEDLINE | ID: mdl-24148124

RESUMO

microRNA are small non coding RNA, which negatively regulate the expression of their targets. Due to their various targets, miRNAs play a key role in number of physiological processes and in oncogenesis. The identification of specific miRNA signatures in various types of tumours, including hepatocellular carcinoma (HCC), highlights the dual role of miRNA, both oncogenes and tumour suppressors. Here, we review the current knowledge concerning the deregulation of miRNA expression in liver disease. All studies focusing on miRNAs argue for their possible use as diagnostic, prognostic and therapeutic markers. Here, we preferentially discuss the promising therapeutic strategies based on miRNAs that have been tested in HCC.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , MicroRNAs/fisiologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/fisiologia , Carcinoma Hepatocelular/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , MicroRNAs/genética , Técnicas de Diagnóstico Molecular/métodos , Terapia de Alvo Molecular/métodos , Prognóstico
15.
Int J Cancer ; 129(3): 680-90, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20949564

RESUMO

Micro-RNAs (miRNA) are currently used as cancer biomarkers for hematological cancers and solid tumors. Osteosarcoma is the first primary malignant bone tumor, characterized by a complex genetic and resistance to conventional treatments. For this latter property, the median survival has not been improved since 1990 despite preoperative administration of chemotherapeutic agents. The prediction of tumor response before chemotherapy treatment would constitute a major progress for this pathology. We assessed in this study if miRNA profiling could surpass the current limitations for osteosarcoma diagnosis. We measured the miRNA expression in different osteosarcoma samples: (i) 27 osteosarcoma paraffin-embedded tumors from patients, (ii) human osteosarcoma cell lines, and (iii) tumors from a syngeneic rat osteosarcoma model, recapitulating human osteosarcoma. miRNA profiles were determined using microfluidic cards performing high-throughput TaqMan(®) -based PCR assays, called TaqMan(®) Low Density Arrays. Osteosarcoma of rat and human origins showed a miRNA signature, which could discriminate good from bad responders. In particular, we identified five discriminating miRNAs (miR-92a, miR-99b, miR-132, miR-193a-5p and miR-422a) in patient tumors, which could be easily transferable to diagnosis. These discriminating miRNAs, as well as those identified in rat, targeted the TGFß, the Wnt and the MAP kinase pathways. These results indicate that our platform constitutes a potent diagnostic tool to predict tumor sensitivity to a drug in attempt to better adapt treatment to tumor biological specificities and also to identify new potential therapeutic strategies.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Ósseas/genética , Ifosfamida/uso terapêutico , MicroRNAs/genética , Osteossarcoma/genética , Animais , Neoplasias Ósseas/tratamento farmacológico , Ciclo Celular , Linhagem Celular Tumoral , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Invasividade Neoplásica , Osteossarcoma/tratamento farmacológico , Ratos , Resultado do Tratamento
16.
Sarcoma ; 2011: 460650, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21437224

RESUMO

Sarcomas are divided into a group with specific alterations and a second presenting a complex karyotype, sometimes difficult to diagnose or with few therapeutic options available. We assessed if miRNA profiling by TaqMan low density arrays could predict the response of undifferentiated rhabdomyosarcoma (RMS) and osteosarcoma to treatment. We showed that miRNA signatures in response to a therapeutic agent (chemotherapy or the mTOR inhibitor RAD-001) were cell and drug specific on cell lines and a rat osteosarcoma model. This miRNA signature was related to cell or tumour sensitivity to this treatment and might be not due to chromosomal aberrations, as revealed by a CGH array analysis of rat tumours. Strikingly, miRNA profiling gave promising results for patient rhabdomyosarcoma, discriminating all types of RMS: (Pax+) or undifferentiated alveolar RMS as well as embryonal RMS. As highlighted by these results, miRNA profiling emerges as a potent molecular diagnostic tool for complex karyotype sarcomas.

17.
World J Hepatol ; 13(9): 979-1002, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34630870

RESUMO

Hepatocellular carcinoma (HCC) is the most common primary liver tumor, which stands fourth in rank of cancer-related deaths worldwide. The incidence of HCC is constantly increasing in correlation with the epidemic in diabetes and obesity, arguing for an urgent need for new treatments for this lethal cancer refractory to conventional treatments. HCC is the paradigm of inflammation-associated cancer, since more than 80% of HCC emerge consecutively to cirrhosis associated with a vast remodeling of liver microenvironment. In the recent decade, immunomodulatory drugs have been developed and have given impressive results in melanoma and later in several other cancers. In the present review, we will discuss the recent advancements concerning the use of immunotherapies in HCC, in particular those targeting immune checkpoints, used alone or in combination with other anti-cancers agents. We will address why these drugs demonstrate unsatisfactory results in a high proportion of liver cancers and the mechanisms of resistance developed by HCC to evade immune response with a focus on the epigenetic-related mechanisms.

18.
Elife ; 92020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33084574

RESUMO

Erythropoietin (EPO) is a key regulator of erythropoiesis. The embryonic liver is the main site of erythropoietin synthesis, after which the kidney takes over. The adult liver retains the ability to express EPO, and we discovered here new players of this transcription, distinct from the classical hypoxia-inducible factor pathway. In mice, genetically invalidated in hepatocytes for the chromatin remodeler Arid1a, and for Apc, the major silencer of Wnt pathway, chromatin was more accessible and histone marks turned into active ones at the Epo downstream enhancer. Activating ß-catenin signaling increased binding of Tcf4/ß-catenin complex and upregulated its enhancer function. The loss of Arid1a together with ß-catenin signaling, resulted in cell-autonomous EPO transcription in mouse and human hepatocytes. In mice with Apc-Arid1a gene invalidations in single hepatocytes, Epo de novo synthesis led to its secretion, to splenic erythropoiesis and to dramatic erythrocytosis. Thus, we identified new hepatic EPO regulation mechanism stimulating erythropoiesis.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Eritropoetina/metabolismo , Hepatócitos/metabolismo , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo , Adulto , Animais , Eritropoese , Feminino , Humanos , Hibridização In Situ , Masculino , Camundongos , Via de Sinalização Wnt
19.
Clin Res Hepatol Gastroenterol ; 43(6): 630-637, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31401041

RESUMO

Despite the intensive efforts to identify the molecular events responsible for the emergence of liver cancer, hepatocellular carcinoma (HCC) remains a major health problem in the world. Thus, the identification of new therapeutic opportunities is a short-term necessity. These last few decades, non-coding RNAs appeared as interesting therapeutic strategies with their pleiotropic inhibitory action in the cell itself but also in recipient cells via their secretion into extracellular vesicles. This short review recapitulates recent advancements concerning non-coding RNAs and their deregulations in liver cancer.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , RNA Longo não Codificante , Humanos
20.
World J Hepatol ; 10(11): 785-789, 2018 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-30533178

RESUMO

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second cause of cancer-related death worldwide. The incidence of HCC is constantly increasing in correlation with the rise in diabetes and obesity, arguing for an urgent need for new developments in the treatment of this lethal cancer. Exosomes are small double-membrane vesicles loaded with distinct cargos, particularly small non-coding RNAs called microRNAs, representative of each donor cell and secreted to affect the features of neighboring cells or recipient cells located further away, like in the case of metastasis. A better understanding of the role of exosomes with a microRNA signature in cancer pathogenesis gave rise to the concept of their use as a non-invasive diagnostic biomarker and in the treatment of cancer, including HCC. In this communication, we review recent works that demonstrate that hepatic stellate cells establish an epigenetic communication with liver cancer cells, which affects their pro-malignant features. If naturally secreted patient-derived exosomes show major limitations concerning their clinical use, bio-engineered exosome mimetics that incorporate controlled components and exhibit no protumoral properties could be promising carriers for the treatment of liver cancers, which is the organ preferentially targeted by systemic injection of exosomes.

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