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1.
Sci Rep ; 14(1): 18551, 2024 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-39122875

RESUMO

Hepatocellular carcinoma (HCC) is the most common liver cancer and is among the leading causes of cancer-related death worldwide. There is no reliable biomarker for the early diagnosis of HCC. Circulating microRNAs (miRNAs) have attracted attention as potential biomarkers of disease. By small-RNA next-generation sequencing, the analysis of serum miRNAs led to the identification of molecular signatures able to discriminate advanced HCC from early HCC (n = 246); advanced HCC from CIRRHOSIS (n = 299); advanced HCC from HEALTHY (n = 320); HEALTHY from early HCC (n = 343); and HEALTHY from CIRRHOSIS (n = 414). Cirrhotic patients and early HCC patients exhibited similar serum miRNA profiles, yet a small number of miRNAs (n = 57) were able to distinguish these two classes of patients. A second objective of the study was to identify serum miRNAs capable of predicting the response to therapy in patients with advanced HCC. All patients were treated with sorafenib as first-line therapy: 24 were nonresponsive and 24 responsive. Analysis of circulating miRNAs revealed a 54 miRNAs signature able to separate the two subgroups. This study suggested that circulating miRNAs could be useful biomarkers for monitoring patients with liver diseases ranging from cirrhosis to advanced HCC and possibly predicting susceptibility to first-line treatment based on sorafenib.


Assuntos
Biomarcadores Tumorais , Carcinoma Hepatocelular , MicroRNA Circulante , Progressão da Doença , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , MicroRNA Circulante/sangue , MicroRNA Circulante/genética , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/diagnóstico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Cirrose Hepática/genética , Cirrose Hepática/tratamento farmacológico , Sorafenibe/uso terapêutico , MicroRNAs/sangue , MicroRNAs/genética , Adulto
2.
Biochim Biophys Acta ; 1822(6): 927-35, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22386878

RESUMO

The reduced expression (haplodeficiency) of the main brain derived neurotrophic factor receptor, namely TrkB is associated with reduced atherosclerosis, smooth muscle cells accumulation and collagen content in the lesion. These data support the concept that brain derived neurotrophic factor of vascular origin may contribute to atherosclerosis. However, to date, no experimental approach was possible to investigate this issue due to the lethality of brain derived neurotrophic factor null mice. To overcome these limitations, we generated a mouse model with a conditional deletion of brain derived neurotrophic factor in endothelial cells (Tie-2 Cre recombinase) on an atherosclerotic prone background (apolipoprotein E knock out) and investigated the effect of conditional brain derived neurotrophic factor deficiency on atherosclerosis. Despite brain derived neurotrophic factor reduction in the vascular wall, mice with conditional deletion of brain derived neurotrophic factor did not develop larger atherosclerotic lesion compared to controls. Smooth muscle cell content as well as the distribution of total and fibrillar collagen was similar in the atherosclerotic lesions from mice with brain derived neurotrophic factor conditional deficiency compared to controls. Finally an extended gene expression analysis failed to identify pro-atherogenic gene expression patterns among the animal with brain derived neurotrophic factor deficiency. In spite of the reduced brain derived neurotrophic factor expression, similar atherosclerosis development was observed in the brain derived neurotrophic factor conditional deficient mouse compared to controls. These pieces of evidence indicate that endothelial derived-brain derived neurotrophic factor is not a pro-atherogenic factor and would rather suggest to investigate the role of other TrkB activators on atherosclerosis.


Assuntos
Apolipoproteínas E/metabolismo , Aterosclerose/metabolismo , Aterosclerose/patologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Fator Neurotrófico Derivado do Encéfalo/deficiência , Fator Neurotrófico Derivado do Encéfalo/genética , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Integrases/genética , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores Proteína Tirosina Quinases/genética , Receptor TIE-2 , Receptor trkB/metabolismo , Deleção de Sequência
3.
Mol Cancer ; 12(1): 130, 2013 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-24165569

RESUMO

BACKGROUND: The microRNA 125b is a double-faced gene expression regulator described both as a tumor suppressor gene (in solid tumors) and an oncogene (in hematologic malignancies). In human breast cancer, it is one of the most down-regulated miRNAs and is able to modulate ERBB2/3 expression. Here, we investigated its targets in breast cancer cell lines after miRNA-mimic transfection. We examined the interactions of the validated targets with ERBB2 oncogene and the correlation of miR-125b expression with clinical variables. METHODS: MiR-125b possible targets were identified after transfecting a miRNA-mimic in MCF7 cell line and analyzing gene expression modifications with Agilent microarrays and Sylamer bioinformatic tool. Erythropoietin (EPO) and its receptor (EPOR) were validated as targets of miR-125b by luciferase assay and their expression was assessed by RT-qPCR in 42 breast cancers and 13 normal samples. The molecular talk between EPOR and ERBB2 transcripts, through miR-125b, was explored transfecting MDA-MD-453 and MDA-MB-157 with ERBB2 RNA and using RT-qPCR. RESULTS: We identified a panel of genes down-regulated after miR-125b transfection and putative targets of miR-125b. Among them, we validated erythropoietin (EPO) and its receptor (EPOR) - frequently overexpressed in breast cancer--as true targets of miR-125b. Moreover, we explored possible correlations with clinical variables and we found a down-regulation of miR-125b in metastatic breast cancers and a significant positive correlation between EPOR and ERBB2/HER2 levels, that are both targets of miR-125b and function as competing endogenous RNAs (ceRNAs). CONCLUSIONS: Taken together our results show a mechanism for EPO/EPOR and ERBB2 co-regulation in breast cancer and confirm the importance of miR-125b in controlling clinically-relevant cancer features.


Assuntos
Neoplasias da Mama/metabolismo , Eritropoetina/genética , MicroRNAs/genética , Interferência de RNA , Receptor ErbB-2/metabolismo , Receptores da Eritropoetina/genética , Regiões 3' não Traduzidas , Sítios de Ligação , Neoplasias da Mama/patologia , Eritropoetina/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Células HEK293 , Humanos , Células MCF-7 , Anotação de Sequência Molecular , Metástase Neoplásica , Receptor ErbB-2/genética , Receptores da Eritropoetina/metabolismo
4.
Hepatology ; 56(3): 1025-33, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22473819

RESUMO

UNLABELLED: MicroRNA-221 (miR-221) is one of the most frequently and consistently up-regulated microRNAs (miRNAs) in human cancer. It has been hypothesized that miR-221 may act as a tumor promoter. To demonstrate this, we developed a transgenic (TG) mouse model that exhibits an inappropriate overexpression of miR-221 in the liver. Immunoblotting and immunostaining confirmed a concomitant down-regulation of miR-221 target proteins. This TG model is characterized by the emergence of spontaneous nodular liver lesions in approximately 50% of male mice and by a strong acceleration of tumor development in 100% of mice treated with diethylnitrosamine. Similarly to human hepatocellular carcinoma, tumors are characterized by a further increase in miR-221 expression and a concomitant inhibition of its target protein-coding genes (i.e., cyclin-dependent kinase inhibitor [Cdkn]1b/p27, Cdkn1c/p57, and B-cell lymphoma 2-modifying factor). To validate the tumor-promoting effect of miR-221, we showed that in vivo delivery of anti-miR-221 oligonucleotides leads to a significant reduction of the number and size of tumor nodules. CONCLUSIONS: This study not only establishes that miR-221 can promote liver tumorigenicity, but it also establishes a valuable animal model to perform preclinical investigations for the use of anti-miRNA approaches aimed at liver cancer therapy.


Assuntos
Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/fisiologia , Animais , Masculino , Camundongos , Camundongos Transgênicos
5.
J Pathol ; 227(3): 275-85, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22262409

RESUMO

MiR-519d belongs to the chromosome 19 miRNA cluster (C19MC), the largest human miRNA cluster. One of its members, miR-519d, is over-expressed in hepatocellular carcinoma (HCC) and we characterized its contribution to hepatocarcinogenesis. In HCC cells, the over-expression of miR-519d promotes cell proliferation, invasion and impairs apoptosis following anticancer treatments. These functions are, at least in part, exerted through the direct targeting of CDKN1A/p21, PTEN, AKT3 and TIMP2. The mechanisms underlying miR-519d aberrant expression in HCC were assayed by genomic DNA amplification, methylation analysis and ChIP assay. The aberrant hypomethylation of C19MC and TP53 were respectively identified as an epigenetic change allowing the aberrant expression of miR-519d and one of the factors able to activate its transcription. In conclusion, we assessed the oncogenic role of miR-519d in HCC by characterizing its biological functions, including the modulation of response to anticancer treatments and by identifying CDKN1A/p21, PTEN, AKT3 and TIMP2 among its targets.


Assuntos
Carcinoma Hepatocelular/enzimologia , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Metilação de DNA , Neoplasias Hepáticas/enzimologia , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/farmacologia , Apoptose , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina , Inibidor de Quinase Dependente de Ciclina p21/genética , Doxorrubicina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas c-akt/genética , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos , Inibidor Tecidual de Metaloproteinase-2/genética , Transcrição Gênica/efeitos dos fármacos , Transfecção , Proteína Supressora de Tumor p53/genética , Regulação para Cima
6.
Life (Basel) ; 12(12)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36556413

RESUMO

Metagenomic Next Generation Sequencing (mNGS) allows the evaluation of complex microbial communities, avoiding isolation and cultivation of each microbial species, and does not require prior knowledge of the microbial sequences present in the sample. Applications of mNGS include virome characterization, new virus discovery and full-length viral genome reconstruction, either from virus preparations enriched in culture or directly from clinical and environmental specimens. Here, we systematically reviewed studies that describe novel virus identification through mNGS from samples of different origin (plant, animal and environment). Without imposing time limits to the search, 379 publications were identified that met the search parameters. Sample types, geographical origin, enrichment and nucleic acid extraction methods, sequencing platforms, bioinformatic analytical steps and identified viral families were described. The review highlights mNGS as a feasible method for novel virus discovery from samples of different origins, describes which kind of heterogeneous experimental and analytical protocols are currently used and provides useful information such as the different commercial kits used for the purification of nucleic acids and bioinformatics analytical pipelines.

7.
Mol Ther Nucleic Acids ; 29: 538-549, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36035756

RESUMO

Palbociclib is in early-stage clinical testing in advanced hepatocellular carcinoma (HCC). Here, we investigated whether the anti-tumor activity of palbociclib, which prevents the CDK4/6-mediated phosphorylation of RB1 but simultaneously activates AKT signaling, could be improved by its combination with a PI3K/AKT/mTOR inhibitor in liver cancer models. The selective pan-AKT inhibitor, MK-2206, or the microRNA-199a-3p were tested in combination with palbociclib in HCC cell lines and in the TG221 HCC transgenic mouse model. The combination palbociclib/MK-2206 was highly effective, but too toxic to be tolerated by mice. Conversely, the combination miR-199a-3p mimics/palbociclib not only induced a complete or partial regression of tumor lesions, but was also well tolerated. After 3 weeks of treatment, the combination produced a significant reduction in number and size of tumor nodules in comparison with palbociclib or miR-199a-3p mimics used as single agents. Moreover, we also reported the efficacy of this combination against sorafenib-resistant cells in vitro and in vivo. At the molecular level, the combination caused the simultaneous decrease of the phosphorylation of both RB1 and of AKT. Our findings provide pre-clinical evidence for the efficacy of the combination miR-199a-3p/palbociclib as anti-HCC treatment or as a new approach to overcome sorafenib resistance.

9.
Blood ; 113(25): 6411-8, 2009 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-19211935

RESUMO

Aberrant DNA hypermethylation contributes to myeloid leukemogenesis by silencing structurally normal genes involved in hematopoiesis. MicroRNAs (miRNAs) are noncoding RNAs that regulate gene expression by targeting protein-coding mRNAs. Recently, miRNAs have been shown to play a role as both targets and effectors in gene hypermethylation and silencing in malignant cells. In the current study, we showed that enforced expression of miR-29b in acute myeloid leukemia cells resulted in marked reduction of the expression of DNA methyltransferases DNMT1, DNMT3A, and DNMT3B at both RNA and protein levels. This in turn led to decrease in global DNA methylation and reexpression of p15(INK4b) and ESR1 via promoter DNA hypomethylation. Although down-regulation of DNMT3A and DNMT3B was the result of a direct interaction of miR-29b with the 3' untranslated regions of these genes, no predicted miR-29b interaction sites were found in the DNMT1 3' untranslated regions. Further experiments revealed that miR-29b down-regulates DNMT1 indirectly by targeting Sp1, a transactivator of the DNMT1 gene. Altogether, these data provide novel functional links between miRNAs and aberrant DNA hypermethylation in acute myeloid leukemia and suggest a potentially therapeutic use of synthetic miR-29b oligonucleotides as effective hypomethylating compounds.


Assuntos
DNA (Citosina-5-)-Metiltransferases/biossíntese , Metilação de DNA/genética , Regulação Leucêmica da Expressão Gênica , Genes Supressores de Tumor , Leucemia Mieloide/genética , MicroRNAs/genética , RNA Neoplásico/genética , Regiões 3' não Traduzidas/genética , Doença Aguda , Diferenciação Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p15/biossíntese , Inibidor de Quinase Dependente de Ciclina p15/genética , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/genética , DNA Metiltransferase 3A , Regulação para Baixo/genética , Indução Enzimática/genética , Receptor alfa de Estrogênio/biossíntese , Receptor alfa de Estrogênio/genética , Vetores Genéticos/genética , Humanos , Vírus da Imunodeficiência Felina/genética , Leucemia Mieloide/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , RNA Neoplásico/biossíntese , Fator de Transcrição Sp1/antagonistas & inibidores , DNA Metiltransferase 3B
10.
Mutat Res ; 717(1-2): 67-76, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21514310

RESUMO

During the recent few years, microRNAs emerged as key molecules in the regulation of mammalian cell functions. It was also shown that their altered expression can promote pathologic conditions, such as cancer and other common diseases. Because environmental exposure to biological, chemical or physical agents may be responsible for human diseases, including cancer, uncovering relationships between exposure to environmental carcinogens and expression of microRNAs may help to disclose early mechanisms of disease and it may potentially lead to the development of useful indicators of toxic exposure or novel biomarkers for carcinogenicity testing. The unique expression profile of microRNAs in different types and at different stages of cancer coupled to their remarkable stability in tissues and in serum/plasma suggests that these little molecules may find application as sensitive biomarkers. This review will concentrate on the alterations in microRNA expression in response to environmental factors in relation to the risk of developing liver cancer.


Assuntos
Poluentes Ambientais/toxicidade , Fígado/efeitos dos fármacos , Fígado/fisiologia , MicroRNAs/metabolismo , Mutagênicos/toxicidade , Aflatoxina B1/toxicidade , Animais , Arsênio/toxicidade , Benzo(a)pireno/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Etanol/toxicidade , Regulação da Expressão Gênica , Hepacivirus/patogenicidade , Vírus da Hepatite B/patogenicidade , Humanos , Fígado/patologia , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , MicroRNAs/genética , Venenos/toxicidade , Fatores de Risco , Rodenticidas/toxicidade , Nicotiana/toxicidade , Triazinas/toxicidade
11.
Cancer Res ; 80(8): 1720-1734, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32015093

RESUMO

The molecular background of hepatocellular carcinoma (HCC) is highly heterogeneous, and biomarkers predicting response to treatments are an unmet clinical need. We investigated miR-30e-3p contribution to HCC phenotype and response to sorafenib, as well as the mutual modulation of TP53/MDM2 pathway, in HCC tissues and preclinical models. MiR-30e-3p was downregulated in human and rat HCCs, and its downregulation associated with TP53 mutations. TP53 contributed to miR-30e-3p biogenesis, and MDM2 was identified among its target genes, establishing an miR-30e-3p/TP53/MDM2 feedforward loop and accounting for miR-30e-3p dual role based on TP53 status. EpCAM, PTEN, and p27 were demonstrated as miR-30e-3p additional targets mediating its contribution to stemness and malignant features. In a preliminary cohort of patients with HCC treated with sorafenib, increased miR-30e-3p circulating levels predicted the development of resistance. In conclusion, molecular background dictates miR-30e-3p dual behavior in HCC. Mdm2 targeting plays a predominant tumor suppressor function in wild-type TP53 contexts, whereas other targets such as PTEN, p27, and EpCAM gain relevance and mediate miR-30e-3p oncogenic role in nonfunctional TP53 backgrounds. Increased circulating levels of miR-30e-3p predict the development of sorafenib resistance in a preliminary series of patients with HCC and deserve future investigations. SIGNIFICANCE: The dual role of miR-30e-3p in HCC clarifies how the molecular context dictates the tumor suppressor or oncogenic function played by miRNAs.


Assuntos
Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , MicroRNAs/fisiologia , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/farmacologia , Sítios de Ligação , Carcinógenos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células , Estudos de Coortes , Dietilnitrosamina , Modelos Animais de Doenças , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Molécula de Adesão da Célula Epitelial/metabolismo , Inativação Gênica , Genes Supressores de Tumor , Genes p53/genética , Células Hep G2 , Xenoenxertos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/metabolismo , Mutação , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas , PTEN Fosfo-Hidrolase/metabolismo , Fenótipo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/genética , Ratos , Sorafenibe/farmacologia , Análise Serial de Tecidos , Proteína Supressora de Tumor p53/genética
12.
Mol Oncol ; 14(9): 2163-2175, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32441866

RESUMO

Cytopathological analyses of bronchial washings (BWs) collected during fibre-optic bronchoscopy are often inconclusive for lung cancer diagnosis. To address this issue, we assessed the suitability of conducting molecular analyses on BWs, with the aim to improve the diagnosis and outcome prediction of lung cancer. The methylation status of RASSF1A, CDH1, DLC1 and PRPH was analysed in BW samples from 91 lung cancer patients and 31 controls, using a novel two-colour droplet digital methylation-specific PCR (ddMSP) technique. Mutations in ALK, BRAF, EGFR, ERBB2, KRAS, MAP2K1, MET, NRAS, PIK3CA, ROS1 and TP53 and gene fusions of ALK, RET and ROS1 were also investigated, using next-generation sequencing on 73 lung cancer patients and 14 tumour-free individuals. Our four-gene methylation panel had significant diagnostic power, with 97% sensitivity and 74% specificity (relative risk, 7.3; odds ratio, 6.1; 95% confidence interval, 12.7-127). In contrast, gene mutation analysis had a remarkable value for predictive, but not for diagnostic, purposes. Actionable mutations in EGFR, HER2 and ROS1 as well as in other cancer genes (KRAS, PIK3CA and TP53) were detected. Concordance with gene mutations uncovered in tumour biopsies was higher than 90%. In addition, bronchial-washing analyses permitted complete patient coverage and the detection of additional actionable mutations. In conclusion, BWs are a useful material on which to perform molecular tests based on gene panels: aberrant gene methylation and mutation analyses could be performed as approaches accompanying current diagnostic and predictive assays during the initial workup phase. This study establishes the grounds for further prospective investigation.


Assuntos
Lavagem Broncoalveolar , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Técnicas de Diagnóstico Molecular , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Metilação de DNA/genética , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação/genética
13.
Cancers (Basel) ; 11(11)2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31739536

RESUMO

Hepatocellular carcinoma (HCC) is a deadly disease and therapeutic efficacy in advanced HCC is limited. Since progression of chronic liver disease to HCC involves a long latency period of a few decades, a significant window of therapeutic opportunities exists for prevention of HCC and improve patient prognosis. Nonetheless, there has been no clinical advancement in instituting HCC chemopreventive strategies. Some of the major challenges are heterogenous genetic aberrations of HCC, significant modulation of tumor microenvironment and incomplete understanding of HCC tumorigenesis. To this end, animal models of HCC are valuable tools to evaluate biology of tumor initiation and progression with specific insight into molecular and genetic mechanisms involved. In this review, we describe various animal models of HCC that facilitate effective ways to study therapeutic prevention strategies that have translational potential to be evaluated in a clinical context.

14.
Oncogene ; 38(45): 7035-7045, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31409896

RESUMO

Metformin is a hypoglycaemic agent used to treat type 2 diabetes mellitus (DM2) patients, with a broad safety profile. Since previous epidemiological studies had shown that the incidence of hepatocellular carcinoma (HCC) decreased significantly in metformin treated DM2 patients, we hypothesised that intervention with metformin could reduce the risk of neoplastic transformation of hepatocytes. HCC is the most common primary liver malignancy and it generally originates in a background of liver fibrosis and cirrhosis. In the present study, we took advantage of a transgenic mouse (TG221) characterized by microRNA-221 overexpression, with cirrhotic liver background induced by chronic administration of carbon tetrachloride (CCl4). This mouse model develops fibrosis, cirrhosis and liver tumours that become visible in 100% of mice at 5-6 months of age. Our results demonstrated that metformin intervention improves liver function, inhibits hepatic stellate cell (HSC) activation, reduces liver fibrosis, depletes lipid accumulation in hepatocytes, halts progression to decompensated cirrhosis and abrogates development HCC in CCl4 challenged transgenic mouse model. The study establishes the rationale for investigating metformin in cirrhotic patients regardless of concomitant DM2 status.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Transformação Celular Neoplásica/efeitos dos fármacos , Modelos Animais de Doenças , Fibrose/tratamento farmacológico , Hipoglicemiantes/farmacologia , Neoplasias Hepáticas Experimentais/prevenção & controle , Metformina/farmacologia , Animais , Tetracloreto de Carbono/toxicidade , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/patologia , Fibrose/etiologia , Fibrose/patologia , Humanos , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/patologia , Masculino , Camundongos , Camundongos Transgênicos , MicroRNAs/genética
15.
Cancers (Basel) ; 11(12)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31805631

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related mortality. Molecular heterogeneity and absence of biomarkers for patient allocation to the best therapeutic option contribute to poor prognosis of advanced stages. Aberrant microRNA (miRNA) expression is associated with HCC development and progression and influences drug resistance. Therefore, miRNAs have been assayed as putative biomarkers and therapeutic targets. MiRNA-based therapeutic approaches demonstrated safety profiles and antitumor efficacy in HCC animal models; nevertheless, caution should be used when transferring preclinical findings to the clinics, due to possible molecular inconsistency between animal models and the heterogeneous pattern of the human disease. In this context, models with defined genetic and molecular backgrounds might help to identify novel therapeutic options for specific HCC subgroups. In this review, we describe rodent models of HCC, emphasizing their representativeness with the human pathology and their usefulness as preclinical tools for assessing miRNA-based therapeutic strategies.

16.
Mol Ther Nucleic Acids ; 14: 239-250, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30641476

RESUMO

Most hepatocellular carcinomas (HCCs) arise in the context of chronic liver disease and/or cirrhosis. Thus, chemoprevention in individuals at risk represents an important but yet unproven approach. In this study, we investigated the ability of microRNA (miRNA)-based molecules to prevent liver cancer development in a cirrhotic model. To this end, we developed a mouse model able to recapitulate the natural progression from fibrosis to HCC, and then we tested the prophylactic activity of an miRNA-based approach in the model. The experiments were carried out in the TG221 transgenic mouse, characterized by the overexpression of miR-221 in the liver and predisposed to the development of liver tumors. TG221 as well as wild-type mice were exposed to the hepatotoxin carbon tetrachloride (CCl4) to induce chronic liver damage. All mice developed liver cirrhosis, but only TG221 mice developed nodular lesions in 100% of cases within 6 months of age. The spectrum of lesions ranged from dysplastic foci to carcinomas. To investigate miRNA-based prophylactic approaches, anti-miR-221 oligonucleotides or miR-199a-3p mimics were administered to TG221 CCl4-treated mice. Compared to control animals, a significant reduction in number, size, and, most significantly, malignant phenotype of liver nodules was observed, thus demonstrating an important prophylactic action of miRNA-based molecules. In summary, in this article, we not only report a simple model of liver cancer in a cirrhotic background but also provide evidence for a potential miRNA-based approach to reduce the risk of HCC development.

17.
J Med Chem ; 62(3): 1246-1273, 2019 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-30624919

RESUMO

Negative allosteric modulators (NAMs) of the metabotropic glutamate receptor 5 (mGlu5) hold great promise for the treatment of a variety of central nervous system disorders. We have recently reported that prop-2-ynylidenecycloalkylamine derivatives are potent and selective NAMs of the mGlu5 receptor. In this work, we explored the amide, carbamate, sulfonamide, and urea derivatives of prop-2-ynylidenecycloalkylamine compounds with the aim of improving solubility and metabolic stability. In silico and experimental analyses were performed on the synthesized series of compounds to investigate structure-activity relationships. Compounds 12, 32, and 49 of the carbamate, urea, and amide classes, respectively, showed the most suitable cytochrome inhibition and metabolic stability profiles. Among them, compound 12 showed excellent selectivity, solubility, and stability profiles as well as suitable in vitro and in vivo pharmacokinetic properties. It was highly absorbed in rats and dogs and was active in anxiety, neuropathic pain, and lower urinary tract models.


Assuntos
Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacologia , Receptor de Glutamato Metabotrópico 5/efeitos dos fármacos , Regulação Alostérica , Amidas/química , Animais , Disponibilidade Biológica , Células CHO , Carbamatos/química , Cricetulus , Cães , Fármacos Atuantes sobre Aminoácidos Excitatórios/química , Fármacos Atuantes sobre Aminoácidos Excitatórios/farmacocinética , Humanos , Ligantes , Ratos , Relação Estrutura-Atividade , Sulfonamidas/química , Ureia/química
18.
Mol Ther Nucleic Acids ; 11: 485-493, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29858083

RESUMO

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. Prognosis is poor, and therapeutic options are limited. MicroRNAs (miRNAs) have emerged as potential therapeutic molecules against cancer. Here, we investigated the therapeutic efficacy of miR-199a-3p, an miRNA highly expressed in normal liver and downregulated in virtually all HCCs. The therapeutic value of miR-199a-3p mimic molecules was assayed in the TG221 mouse, a transgenic model highly predisposed to the development of liver cancer. Administration of miR-199a-3p mimics in the TG221 transgenic mouse showing liver cancer led to a significant reduction of number and size of tumor nodules compared to control animals. In vivo delivery confirmed protein downregulation of the miR-199a-3p direct targets, mechanistic target of rapamycin (MTOR) and p21 activated kinase 4 (PAK4), ultimately leading to the repression of FOXM1. Remarkably, the anti-tumor activity of miR-199a-3p mimics was comparable to that obtained with sorafenib. These results suggested that miR-199a-3p may be considered a promising HCC therapeutic option.

19.
Clin Cancer Res ; 23(14): 3953-3965, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28096271

RESUMO

Purpose: The aberrant expression of miR-221 is a hallmark of human cancers, including hepatocellular carcinoma (HCC), and its involvement in drug resistance, together with a proved in vivo efficacy of anti-miR-221 molecules, strengthen its role as an attractive target candidate in the oncologic field. The discovery of biomarkers predicting the response to treatments represents a clinical challenge in the personalized treatment era. This study aimed to investigate the possible role of miR-221 as a circulating biomarker in HCC patients undergoing sorafenib treatment as well as to evaluate its contribution to sorafenib resistance in advanced HCC.Experimental Design: A chemically induced HCC rat model and a xenograft mouse model, together with HCC-derived cell lines were employed to analyze miR-221 modulation by Sorafenib treatment. Data from the functional analysis were validated in tissue samples from surgically resected HCCs. The variation of circulating miR-221 levels in relation to Sorafenib treatment were assayed in the animal models and in two independent cohorts of patients with advanced HCC.Results: MiR-221 over-expression was associated with Sorafenib resistance in two HCC animal models and caspase-3 was identified as its target gene, driving miR-221 anti-apoptotic activity following Sorafenib administration. Lower pre-treatment miR-221 serum levels were found in patients subsequently experiencing response to Sorafenib and an increase of circulating miR-221 at the two months assessment was observed in responder patients.Conclusions: MiR-221 might represent a candidate biomarker of likelihood of response to Sorafenib in HCC patients to be tested in future studies. Caspase-3 modulation by miR-221 participates to Sorafenib resistance. Clin Cancer Res; 23(14); 3953-65. ©2017 AACR.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Caspase 3/genética , Neoplasias Hepáticas/tratamento farmacológico , MicroRNAs/genética , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Animais , Apoptose/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Compostos de Fenilureia/efeitos adversos , Sorafenibe , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Circulation ; 111(21): 2805-11, 2005 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-15911702

RESUMO

BACKGROUND: HDL is endowed with cardiovascular protective activities. In addition to its role in reverse cholesterol transport, HDL influences different functions of endothelial cells. In the present study, we investigated in endothelial cells the genes involved in inflammation modulated by HDL. METHODS AND RESULTS: Through cDNA array analysis, transforming growth factor (TGF)-beta2 appeared to be a gene responsive to HDL treatment in endothelial cells. Quantitative real-time polymerase chain reaction confirmed that HDL subfraction 3 selectively induces TGF-beta2 mRNA expression and protein release, whereas TGF-beta1 and TGF-beta3 were not affected. This effect was mainly PI3K/Akt dependent. Lysosphingolipids present in HDL such as sphingosine 1 phosphate and sphingosylphosphorylcholine mimicked the effects of the whole HDL. These results were confirmed in vivo in transgenic mice overexpressing human apolipoprotein (apo) A-I. Compared with apoA-I-knockout mice, phospho-Akt, phospho-ERK1/2, and TGF-beta2 expression was increased in the aorta of transgenic mice overexpressing human apoA-I. In addition, the expression of phospho-Smad2/3, the transcription factor activated by TGF-beta, is increased in transgenic mice compared with knockout mice. CONCLUSIONS: Because TGF-beta possesses antiinflammatory properties and stabilizes the plaque, the results of the present work suggest a novel target for the antiatherosclerotic effect of HDL.


Assuntos
Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Lipoproteínas HDL/farmacologia , Fator de Crescimento Transformador beta/genética , Animais , Apolipoproteínas E/genética , Perfilação da Expressão Gênica , Humanos , Inflamação/genética , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Esfingolipídeos/farmacologia , Fator de Crescimento Transformador beta2
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