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1.
FASEB J ; 37(2): e22731, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36583714

RESUMO

Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by inflammatory responses and fibrotic scar formation leading to cholestasis. Ductular reaction and liver fibrosis are typical liver changes seen in human PSC and cholestasis patients. The current study aimed to clarify the role of liver-specific microRNA-34a in the cholestasis-associated ductular reaction and liver fibrosis. We demonstrated that miR-34a expression was significantly increased in human PSC livers along with the enhanced ductular reaction, cellular senescence, and liver fibrosis. A liver-specific miR-34a knockout mouse was established by crossing floxed miR-34a mice with albumin-promoter-driven Cre mice. Bile duct ligation (BDL) induced liver injury characterized by necrosis, fibrosis, and immune cell infiltration. In contrast, liver-specific miR-34a knockout in BDL mice resulted in decreased biliary ductular pathology associated with the reduced cholangiocyte senescence and fibrotic responses. The miR-34a-mediated ductular reactions may be functioning through Sirt-1-mediated senescence and fibrosis. The hepatocyte-derived conditioned medium promoted LPS-induced fibrotic responses and senescence in cholangiocytes, and miR-34a inhibitor suppressed these effects, further supporting the involvement of paracrine regulation. In conclusion, we demonstrated that liver-specific miR-34a plays an important role in ductular reaction and fibrotic responses in a BDL mouse model of cholestatic liver disease.


Assuntos
Colestase , Hepatopatias , MicroRNAs , Humanos , Camundongos , Animais , Fígado/metabolismo , Cirrose Hepática/metabolismo , Colestase/genética , Colestase/patologia , Ductos Biliares/cirurgia , Ductos Biliares/metabolismo , Ductos Biliares/patologia , Fibrose , Hepatopatias/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo
2.
Hepatology ; 73(5): 1747-1763, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32740973

RESUMO

BACKGROUND AND AIMS: Cholangiocarcinoma (CCA) is a highly lethal disease without effective therapeutic approaches. The whole-genome sequencing data indicate that about 20% of patients with CCA have isocitrate dehydrogenase 1 (IDH1) mutations, which have been suggested to target 2-oxoglutarate (OG)-dependent dioxygenases in promoting CCA carcinogenesis. However, the clinical study indicates that patients with CCA and mutant IDH1 have better prognosis than those with wild-type IDH1, further complicating the roles of 2-OG-dependent enzymes. APPROACH AND RESULTS: This study aimed to clarify if ten-eleven translocation 1 (TET1), which is one of the 2-OG-dependent enzymes functioning in regulating 5-hydroxymethylcytosine (5hmC) formation, is involved in CCA progression. By analyzing The Cancer Genome Atlas (TCGA) data set, TET1 mRNA was found to be substantially up-regulated in patients with CCA when compared with noncancerous bile ducts. Additionally, TET1 protein expression was significantly elevated in human CCA tumors. CCA cells were challenged with α-ketoglutarate (α-KG) and dimethyl-α-KG (DM-α-KG), which are cosubstrates for TET1 dioxygenase. The treatments with α-KG and DM-α-KG promoted 5hmC formation and malignancy of CCA cells. Molecular and pharmacological approaches were used to inhibit TET1 activity, and these treatments substantially suppressed 5hmC and CCA carcinogenesis. Mechanistically, it was found that knockdown of TET1 may suppress CCA progression by targeting cell growth and apoptosis through epigenetic regulation. Consistently, targeting TET1 significantly inhibited CCA malignant progression in a liver orthotopic xenograft model by targeting cell growth and apoptosis. CONCLUSIONS: Our data suggest that expression of TET1 is highly associated with CCA carcinogenesis. It will be important to evaluate TET1 expression in CCA tumors before application of the IDH1 mutation inhibitor because the inhibitor suppresses 2-hydroxyglutarate expression, which may result in activation of TET, potentially leading to CCA malignancy.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/patologia , Isocitrato Desidrogenase/genética , Oxigenases de Função Mista/genética , Proteínas Proto-Oncogênicas/genética , Translocação Genética/genética , Idoso , Neoplasias dos Ductos Biliares/diagnóstico , Neoplasias dos Ductos Biliares/genética , Western Blotting , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/genética , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real , Regulação para Cima
3.
J Pineal Res ; 70(2): e12699, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33020940

RESUMO

Our daily rhythmicity is controlled by a circadian clock with a specific set of genes located in the suprachiasmatic nucleus in the hypothalamus. Mast cells (MCs) are major effector cells that play a protective role against pathogens and inflammation. MC distribution and activation are associated with the circadian rhythm via two major pathways, IgE/FcεRI- and IL-33/ST2-mediated signaling. Furthermore, there is a robust oscillation between clock genes and MC-specific genes. Melatonin is a hormone derived from the amino acid tryptophan and is produced primarily in the pineal gland near the center of the brain, and histamine is a biologically active amine synthesized from the decarboxylation of the amino acid histidine by the L-histidine decarboxylase enzyme. Melatonin and histamine are previously reported to modulate circadian rhythms by pathways incorporating various modulators in which the nuclear factor-binding near the κ light-chain gene in B cells, NF-κB, is the common key factor. NF-κB interacts with the core clock genes and disrupts the production of pro-inflammatory cytokine mediators such as IL-6, IL-13, and TNF-α. Currently, there has been no study evaluating the interdependence between melatonin and histamine with respect to circadian oscillations in MCs. Accumulating evidence suggests that restoring circadian rhythms in MCs by targeting melatonin and histamine via NF-κB may be promising therapeutic strategy for MC-mediated inflammatory diseases. This review summarizes recent findings for circadian-mediated MC functional roles and activation paradigms, as well as the therapeutic potentials of targeting circadian-mediated melatonin and histamine signaling in MC-dependent inflammatory diseases.


Assuntos
Histamina/metabolismo , Mastócitos/metabolismo , Melatonina/metabolismo , Glândula Pineal/metabolismo , Animais , Ritmo Circadiano/fisiologia , Histidina Descarboxilase/metabolismo , Humanos , Interleucina-13/metabolismo , Interleucina-6/metabolismo , Mastócitos/imunologia , Glândula Pineal/imunologia , Fator de Necrose Tumoral alfa/metabolismo
4.
Dig Dis Sci ; 66(4): 1080-1089, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32445050

RESUMO

BACKGROUND: Cholangiocarcinoma is a devastating disease with a 2% 5-year survival if the disease has spread outside the liver. The enzyme aspartate beta-hydroxylase (ASPH) has been demonstrated to be highly expressed in cholangiocarcinoma but not in normal bile ducts and found to stimulate tumor cell migration. In addition, it was found that targeting ASPH inhibits cholangiocarcinoma malignant progression. However, it is not clear whether targeting ASPH with the small molecule inhibitor MO-I-1182 suppresses cholangiocarcinoma metastasis. The current study aims to study the efficacy of MO-I-1182 in suppressing cholangiocarcinoma metastasis. METHODS: The analysis was performed in vitro and in vivo with a preclinical animal model by using molecular and biochemical strategies to regulate ASPH expression and function. RESULTS: Knockdown of ASPH substantially inhibited cell migration and invasion in two human cholangiocarcinoma cell lines. Targeting ASPH with a small molecule inhibitor suppressed cholangiocarcinoma progression. Molecular mechanism studies demonstrated that knockdown of ASPH subsequently suppressed protein levels of the matrix metalloproteinases. The ASPH knockdown experiments suggest that this enzyme may modulate cholangiocarcinoma metastasis by regulating matrix metalloproteinases expression. Furthermore, using an ASPH inhibitor in a rat cholangiocarcinoma intrahepatic model established with BED-Neu-CL#24 cholangiocarcinoma cells, it was found that targeting ASPH inhibited intrahepatic cholangiocarcinoma metastasis and downstream expression of the matrix metalloproteinases. CONCLUSION: ASPH may modulate cholangiocarcinoma metastasis via matrix metalloproteinases expression. Taken together, targeting ASPH function may inhibit intrahepatic cholangiocarcinoma metastasis and improve survival.


Assuntos
Proteínas de Ligação ao Cálcio , Colangiocarcinoma , Inibidores Enzimáticos/farmacologia , Neoplasias Hepáticas , Proteínas de Membrana , Oxigenases de Função Mista , Proteínas Musculares , Metástase Neoplásica/prevenção & controle , Animais , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Proteínas de Ligação ao Cálcio/antagonistas & inibidores , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patologia , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Metaloproteinases da Matriz/metabolismo , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/metabolismo , Proteínas Musculares/antagonistas & inibidores , Proteínas Musculares/metabolismo , Ratos
5.
FASEB J ; 33(2): 1824-1835, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30188753

RESUMO

The 5-hydroxymethylcytosine (5hmc) is a newly identified epigenetic modification thought to be regulated by the TET family of proteins. Little information is available about how ethanol consumption may modulate 5hmC formation and alcoholic liver disease (ALD) progression. A rat ALD model was used to study 5hmC in relationship to hepatocyte apoptosis. Human ALD liver samples were also used to validate these findings. It was found that chronic ethanol feeding significantly reduced 5hmC formation in a rat ALD model. There were no significant changes in TET2 and TET3 between the control- and ethanol-fed animals. In contrast, methylcytosine dioxygenase TET1 (TET1) expression was substantially reduced in the ethanol-fed rats and was accompanied by increased hepatocyte apoptosis. Similarly, knockdown of TET1 in human hepatocyte-like cells also significantly promoted apoptosis. Down-regulation of TET1 resulted in elevated expression of the DNA damage marker, suggesting a role for 5hmc in hepatocyte DNA damage as well. Mechanistic studies revealed that inhibition of TET1 promoted apoptotic gene expression. Similarly, targeting TET1 activity by removing cosubstrate promoted apoptosis and DNA damage. Furthermore, treatment with 5-azacitidine significantly mimics these effects, suggesting that chronic ethanol consumption promotes hepatocyte apoptosis and DNA damage by diminishing TET1-mediated 5hmC formation and DNA methylation. In summary, the current study provides a novel molecular insight that TET1-mediated 5hmC is involved in hepatocyte apoptosis in ALD progression.-Ji, C., Nagaoka, K., Zou, J., Casulli, S., Lu, S., Cao, K. Y., Zhang, H., Iwagami, Y., Carlson, R. I., Brooks, K., Lawrence, J., Mueller, W., Wands, J. R., Huang, C.-K. Chronic ethanol-mediated hepatocyte apoptosis links to decreased TET1 and 5-hydroxymethylcytosine formation.


Assuntos
5-Metilcitosina/análogos & derivados , Apoptose/efeitos dos fármacos , Etanol/toxicidade , Hepatócitos/efeitos dos fármacos , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , 5-Metilcitosina/biossíntese , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Dano ao DNA , Desferroxamina/farmacologia , Regulação para Baixo , Epigênese Genética , Técnicas de Silenciamento de Genes , Hepatócitos/citologia , Humanos , Hepatopatias Alcoólicas/metabolismo , Oxigenases de Função Mista/genética , Proteínas Nucleares/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
6.
J Cell Mol Med ; 22(8): 3987-3995, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29873178

RESUMO

MicroRNAs (miRs) have been recently shown to be heavily involved in the development of alcoholic liver disease (ALD) and suggested as a potential therapeutic target in ALD. The miR-34a was consistently reported to be significantly elevated in several ALD rodent models, but it remains unclear how miR-34a modulates the cellular behaviours of hepatocytes in ALD development and progression. This study aims to characterize alcohol-induced miR-34a impact on hepatocytes growth and apoptosis. The miRNA array was performed to assess changes in miRNA after chronic alcohol feeding. Liver and blood samples were used to examine ALD progression. The miR-34a was overexpressed in human hepatocytes to evaluate its impact on cell growth and apoptosis. Real-time quantitative PCR and Western blot were used to determine the growth and apoptosis molecular signalling pathways associated with miR-34a. Alcohol feeding significantly promoted fatty liver progression, serum ALT levels, apoptosis and miR-34a expression in rat liver. Overexpression of miR-34a in human hepatocytes suppressed cell growth signallings, including c-Met, cyclin D1 and cyclin-dependent kinase 6 (CDK6). The miR-34a might also inhibit the expression of sirtuin 1 (Sirt1) and its target, B-cell lymphoma 2. Interestingly, the expression of miR-34a reverses the suppressive effects of ethanol on cell growth. But, miR-34a promotes hepatocyte senescence and apoptosis. Although the miR-34a-mediated down-regulation of cell growth-associated genes may contribute to cell growth retardation, other miR-34a targets, such as Sirt1, may reverse this phenotype. Future studies will be needed to clarify the role of miR-34a in ALD progression.

7.
J Cell Mol Med ; 21(5): 986-992, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28224705

RESUMO

Exosomes are small vesicles that were initially thought to be a mechanism for discarding unneeded membrane proteins from reticulocytes. Their mediation of intercellular communication appears to be associated with several biological functions. Current studies have shown that most mammalian cells undergo the process of exosome formation and utilize exosome-mediated cell communication. Exosomes contain various microRNAs, mRNAs and proteins. They have been reported to mediate multiple functions, such as antigen presentation, immune escape and tumour progression. This concise review highlights the findings regarding the roles of exosomes in liver diseases, particularly hepatitis B, hepatitis C, liver cirrhosis and hepatocellular carcinoma. However, further elucidation of the contributions of exosomes to intercellular information transmission is needed. The potential medical applications of exosomes in liver diseases seem practical and will depend on the ingenuity of future investigators and their insights into exosome-mediated biological processes.


Assuntos
Carcinoma Hepatocelular/metabolismo , Exossomos/metabolismo , Hepatite/metabolismo , Cirrose Hepática/metabolismo , Neoplasias Hepáticas/metabolismo , Animais , Humanos , Modelos Biológicos
8.
Hepatology ; 63(4): 1213-26, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26683595

RESUMO

UNLABELLED: Aspartate ß-hydroxylase (ASPH) is an enzyme overexpressed in human hepatocellular carcinoma (HCC) tumors that participates in the malignant transformation process. We determined if ASPH was a therapeutic target by exerting effects on cellular senescence to retard HCC progression. ASPH knockdown or knockout was achieved by short hairpin RNAs or the CRISPR/Cas9 system, respectively, whereas enzymatic inhibition was rendered by a potent second-generation small molecule inhibitor of ASPH. Alterations of cell proliferation, colony formation, and cellular senescence were evaluated in human HCC cell lines. The potential mechanisms for activating cellular senescence were explored using murine subcutaneous and orthotopic xenograft models. Inhibition of ASPH expression and enzymatic activity significantly reduced cell proliferation and colony formation but induced tumor cell senescence. Following inhibition of ASPH activity, phosphorylation of glycogen synthase kinase 3ß and p16 expression were increased to promote senescence, whereas cyclin D1 and proliferating cell nuclear antigen were decreased to reduce cell proliferation. The mechanisms involved demonstrate that ASPH binds to glycogen synthase kinase 3ß and inhibits its subsequent interactions with protein kinase B and p38 upstream kinases as shown by coimmunoprecipitation. In vivo experiments demonstrated that small molecule inhibitor treatment of HCC bearing mice resulted in significant dose-dependent reduced tumor growth, induced phosphorylation of glycogen synthase kinase 3ß, enhanced p16 expression in tumor cells, and promoted cellular senescence. CONCLUSIONS: We have identified a new mechanism that promotes HCC growth and progression by modulating senescence of tumor cells; these findings suggest that ASPH enzymatic activity is a novel therapeutic target for HCC.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma Hepatocelular/enzimologia , Senescência Celular/fisiologia , Quinase 3 da Glicogênio Sintase/metabolismo , Neoplasias Hepáticas/enzimologia , Proteínas de Membrana/metabolismo , Oxigenases de Função Mista/metabolismo , Proteínas Musculares/metabolismo , Animais , Carcinoma Hepatocelular/patologia , Proliferação de Células , Modelos Animais de Doenças , Feminino , Glicogênio Sintase Quinase 3 beta , Xenoenxertos , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Nus , Fosforilação , Distribuição Aleatória , Sensibilidade e Especificidade , Células Tumorais Cultivadas
10.
J Hepatol ; 63(1): 191-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25724365

RESUMO

BACKGROUND & AIMS: Alcoholic liver disease (ALD) is characterized by the development of fatty liver, alcoholic hepatitis, fibrosis and cirrhosis. However, the underlying mechanism(s) associated with progression remains elusive. Pro-inflammatory cytokines have been implicated in ALD progression due to pro-apoptotic effects on hepatocytes. Wnt/ß-catenin signaling recently has been shown to promote inflammation and apoptosis, suggesting that activation of this signaling pathway may modulate ALD progression. The current study was designed to test whether pharmacological activation of Wnt/ß-catenin signaling altered ALD development and progression in a rat model. METHODS: Adult male Long Evans rats were fed with isocaloric liquid diets containing 0% or 37% ethanol for 8 weeks, and also treated with Wnt agonist during the last 3 weeks of the feeding regimen. Liver and blood samples were subjected to histology, TUNEL assay, immunoblot analysis, real-time quantitative PCR, and alanine transaminase (ALT) assay. RESULTS: Wnt/ß-catenin signaling was negatively correlated with Foxo3A expression and reduced steatosis, cellular injury and apoptosis in ALD rats. Mutation experiments demonstrated that Foxo3A was critical for modulating these effects. Activation of Wnt/ß-catenin signaling suppressed Foxo3A-induced apoptosis through upregulation of serum/glucocorticoid regulated kinase 1 (SGK1). Moreover, pharmacological restoration of Wnt/ß-catenin signaling reduced ALD progression in vivo. CONCLUSIONS: Wnt/ß-catenin signaling plays a protective role in ALD progression via antagonizing Foxo3A-induced apoptosis, and activation of the Wnt/ß-catenin signaling cascade attenuates ALD progression.


Assuntos
DNA/genética , Hepatopatias Alcoólicas/genética , Regulação para Cima , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Apoptose , Células Cultivadas , Modelos Animais de Doenças , Progressão da Doença , Immunoblotting , Imuno-Histoquímica , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/patologia , Masculino , Ratos , Ratos Long-Evans , Reação em Cadeia da Polimerase em Tempo Real , beta Catenina/metabolismo
11.
Hepatology ; 60(4): 1302-13, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24954865

RESUMO

UNLABELLED: Hepatocellular carcinoma (HCC) has a poor prognosis as a result of widespread intra- and extrahepatic metastases. There is an urgent need to understand signaling cascades that promote disease progression. Aspartyl-(asparaginyl)-ß-hydroxylase (ASPH) is a cell-surface enzyme that generates enhanced cell motility, migration, invasion, and metastatic spread in HCC. We hypothesize that inhibition of its enzymatic activity could have antitumor effects. Small molecule inhibitors (SMIs) were developed based on the crystal structure of the ASPH catalytic site followed by computer-assisted drug design. Candidate compounds were tested for inhibition of ß-hydroxylase activity and selected for their capability to modulate cell proliferation, migration, invasion, and colony formation in vitro and to inhibit HCC tumor growth in vivo using orthotopic and subcutaneous murine models. The biological effects of SMIs on the Notch signaling cascade were evaluated. The SMI inhibitor, MO-I-1100, was selected because it reduced ASPH enzymatic activity by 80% and suppressed HCC cell migration, invasion, and anchorage-independent growth. Furthermore, substantial inhibition of HCC tumor growth and progression was observed in both animal models. The mechanism(s) for this antitumor effect was associated with reduced activation of Notch signaling both in vitro and in vivo. CONCLUSIONS: These studies suggest that the enzymatic activity of ASPH is important for hepatic oncogenesis. Reduced ß-hydroxylase activity generated by the SMI MO-I-1100 leads to antitumor effects through inhibiting Notch signaling cascade in HCC. ASPH promotes the generation of an HCC malignant phenotype and represents an attractive molecular target for therapy of this fatal disease.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana/metabolismo , Oxigenases de Função Mista/metabolismo , Animais , Biomarcadores Tumorais/antagonistas & inibidores , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Feminino , Furanos/farmacologia , Xenoenxertos , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/patologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/efeitos dos fármacos , Camundongos , Camundongos Nus , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/efeitos dos fármacos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/fisiopatologia , Receptores Notch/antagonistas & inibidores , Receptores Notch/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ácidos Sulfônicos/farmacologia
12.
Stem Cells ; 32(9): 2299-308, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24740898

RESUMO

Stem/progenitor (S/P) cells are special types of cells that have the ability to generate tissues throughout their entire lifetime and play key roles in the developmental process. Androgen and the androgen receptor (AR) signals are the critical determinants in male gender development, suggesting that androgen and AR signals might modulate the behavior of S/P cells. In this review, we summarize the AR effects on the behavior of S/P cells, including self-renewal, proliferation, apoptosis, and differentiation in normal S/P cells, as well as proliferation, invasion, and self-renewal in prostate cancer S/P cells. AR plays a protective role in the oxidative stress-induced apoptosis in embryonic stem cells. AR inhibits the self-renewal of embryonic stem cells, bone marrow stromal cells, and prostate S/P cells, but promotes their differentiation except for adipogenesis. However, AR promotes the proliferation of hematopoietic S/P cells and stimulates hematopoietic lineage differentiation. In prostate cancer S/P cells, AR suppresses their self-renewal, metastasis, and invasion. Together, AR differentially influences the characteristics of normal S/P cells and prostate cancer S/P cells, and targeting AR might improve S/P cell transplantation therapy, especially in embryonic stem cells and bone marrow stromal cells.


Assuntos
Próstata/citologia , Receptores Androgênicos/fisiologia , Células-Tronco/citologia , Animais , Diferenciação Celular/fisiologia , Linhagem da Célula , Proliferação de Células/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Próstata/metabolismo , Receptores Androgênicos/metabolismo , Células-Tronco/metabolismo
13.
Alcohol Clin Exp Res ; 39(6): 969-79, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25903395

RESUMO

BACKGROUND: The Wnt/ß-catenin pathway regulates liver growth, repair, and regeneration. Chronic ethanol (EtOH) exposure blunts normal liver regenerative responses, in part by inhibiting insulin/IGF signaling, and correspondingly, previous studies showed that EtOH-impaired liver regeneration could be restored by insulin sensitizer (proliferator-activated receptor [PPAR]-δ agonist) treatment. As Wnt/ß-catenin functions overlap and cross talk with insulin/IGF pathways, we investigated the effects of EtOH exposure and PPAR-δ agonist treatment on Wnt pathway gene expression in relation to liver regeneration. METHODS: Adult male Long Evans rats were fed with isocaloric liquid diets containing 0 or 37% EtOH for 8 weeks and also treated with vehicle or a PPAR-δ agonist during the last 3 weeks of the feeding regimen. The rats were then subjected to 70% partial hepatectomy (PH) and livers harvested at various post-PH time points were used to quantitate expression of 19 Wnt pathway genes using Quantigene 2.0 Multiplex Assay. RESULTS: EtOH broadly inhibited expression of Wnt/ß-catenin signaling-related genes, including down-regulation of Wnt1, Fzd3, Lef1, and Bcl9 throughout the post-PH time course (0 to 72 hours), and suppression of Wnt7a, Ccnd1, Fgf4, Wif1, Sfrp2, and Sfrp5 at 18- and 24-hour post-PH time points. PPAR-δ agonist treatments rescued the EtOH-induced suppression of Wnt1, Wnt7a, Fzd3, Lef1, Bcl9, Ccnd1, and Sfrp2 gene expression in liver, corresponding with the improvements in DNA synthesis and restoration of hepatic architecture. CONCLUSIONS: Chronic high-dose EtOH exposures inhibit Wnt signaling, which likely contributes to the impairments in liver regeneration. Therapeutic effects of PPAR-δ agonists extend beyond restoration of insulin/IGF signaling mechanisms and are mediated in part by enhancement of Wnt pathway signaling. Future studies will determine the degree to which targeted restoration of Wnt signaling is sufficient to improve liver regeneration and remodeling in the context of chronic EtOH exposure.


Assuntos
Etanol/farmacologia , PPAR delta/agonistas , Fenoxiacetatos/farmacologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Expressão Gênica/efeitos dos fármacos , Hepatectomia , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Regeneração Hepática/efeitos dos fármacos , Regeneração Hepática/genética , Masculino , Dados de Sequência Molecular , Ratos , Ratos Long-Evans , Via de Sinalização Wnt/genética
14.
J Biol Chem ; 288(23): 16476-16483, 2013 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-23609451

RESUMO

Prostate cancer (PCa) stem/progenitor cells are known to have higher chemoresistance than non-stem/progenitor cells, but the underlying molecular mechanism remains unclear. We found the expression of testicular nuclear receptor 4 (TR4) is significantly higher in PCa CD133(+) stem/progenitor cells compared with CD133(-) non-stem/progenitor cells. Knockdown of TR4 levels in the established PCa stem/progenitor cells and the CD133(+) population of the C4-2 PCa cell line with lentiviral TR4 siRNA led to increased drug sensitivity to the two commonly used chemotherapeutic drugs, docetaxel and etoposide, judging from significantly reduced IC50 values and increased apoptosis in the TR4 knockdown cells. Mechanism dissection studies found that suppression of TR4 in these stem/progenitor cells led to down-regulation of Oct4 expression, which, in turn, down-regulated the IL-1 receptor antagonist (IL1Ra) expression. Neutralization experiments via adding these molecules into the TR4 knockdown PCa stem/progenitor cells reversed the chemoresistance, suggesting that the TR4-Oct4-IL1Ra axis may play a critical role in the development of chemoresistance in the PCa stem/progenitor cells. Together, these studies suggest that targeting TR4 may alter chemoresistance of PCa stem/progenitor cells, and this finding provides the possibility of targeting TR4 as a new and better approach to overcome the chemoresistance problem in PCa therapeutics.


Assuntos
Antígenos CD , Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Etoposídeo/farmacologia , Glicoproteínas , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Peptídeos , Neoplasias da Próstata , Receptores de Esteroides/metabolismo , Receptores dos Hormônios Tireóideos/metabolismo , Taxoides/farmacologia , Antígeno AC133 , Linhagem Celular Tumoral , Docetaxel , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Silenciamento de Genes , Humanos , Proteína Antagonista do Receptor de Interleucina 1/genética , Masculino , Células-Tronco Neoplásicas/patologia , Fator 3 de Transcrição de Octâmero/genética , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores de Esteroides/genética , Receptores dos Hormônios Tireóideos/genética
15.
Biochim Biophys Acta ; 1833(5): 1222-34, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23333872

RESUMO

Bone marrow derived mesenchymal stem cells (BM-MSCs) have been widely applied in several clinical trials of diseases, such as myocardial infarction, liver cirrhosis, neurodegenerative disease, and osteogenesis imperfecta. Although most studies demonstrated that transplantation of BM-MSCs did exert a temporary relief and short-term therapeutic effects, eventually all symptoms recur, therefore it is essential to improve the therapeutic efficacy of transplantation by either elevating the self-renewal of BM-MSCs or enhancing their survival rate. Herein we demonstrated that the BM-MSCs and adipocyte derived mesenchymal stem cells (ADSCs) isolated from the androgen receptor (AR) knockout mice have higher self-renewal ability than those obtained from the wild-type mice. Knockdown of AR in MSC cell lines exhibited similar results. Mechanistic dissection studies showed that the depletion of AR resulted in activation of Erk and Akt signaling pathways through epidermal growth factor receptor (EGFR) activation or pathway to mediate higher self-renewal of BM-MSCs. Targeting AR signals using ASC-J9® (an AR degradation enhancer), hydroxyflutamide (antagonist of AR), and AR-siRNA all led to enhanced self-renewal of MSCs, suggesting the future possibility of using these anti-AR agents in therapeutic approaches.


Assuntos
Adipócitos , Receptores ErbB , Células-Tronco Mesenquimais , Receptores Androgênicos , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular , Linhagem Celular , Receptores ErbB/genética , Receptores ErbB/metabolismo , Flutamida/análogos & derivados , Flutamida/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Camundongos , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais
16.
Am J Pathol ; 182(2): 460-73, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23219429

RESUMO

Using androgen receptor (AR) knockout mice to determine AR functions in selective prostate cancer (PCa) cells, we determined that AR might play differential roles in various cell types, either to promote or suppress PCa development/progression. These observations partially explain the failure of current androgen deprivation therapy (ADT) to reduce/prevent androgen binding to AR in every cell. Herein, we identified the AR degradation enhancer ASC-J9, which selectively degrades AR protein via interruption of the AR-AR selective coregulator interaction. Such selective interruption could, therefore, suppress AR-mediated PCa growth in the androgen-sensitive stage before ADT and in the castration-resistant stage after ADT. Mechanistic dissection suggested that ASC-J9 could activate the proteasome-dependent pathway to promote AR degradation through the enhanced association of AR-Mdm2 complex. The consequences of ASC-J9-promoted AR degradation included reduced androgen binding to AR, AR N-C terminal interaction, and AR nuclear translocation. Such inhibitory regulation could then result in suppression of AR transactivation and AR-mediated cell growth in eight different mouse models, including intact or castrated nude mice xenografted with androgen-sensitive LNCaP cells or androgen-insensitive C81 cells and castrated nude mice xenografted with castration-resistant C4-2 and CWR22Rv1 cells, and TRAMP and Pten(+/-) mice. These results demonstrate that ASC-J9 could serve as an AR degradation enhancer that effectively suppresses PCa development/progression in the androgen-sensitive and castration-resistant stages.


Assuntos
Castração , Curcumina/análogos & derivados , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Quimioprevenção , Curcumina/efeitos adversos , Curcumina/uso terapêutico , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas com Domínio LIM/metabolismo , Masculino , Camundongos , Camundongos Nus , Coativadores de Receptor Nuclear/metabolismo , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/metabolismo , Próstata/efeitos dos fármacos , Próstata/cirurgia , Neoplasias da Próstata/cirurgia , Proteólise/efeitos dos fármacos , Receptores Androgênicos/genética , Transcrição Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Hepatology ; 57(4): 1550-63, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23150236

RESUMO

UNLABELLED: Transplantation of bone marrow mesenchymal stem cells (BM-MSCs) has been considered as an alternative therapy, replacing liver transplantation in clinical trials, to treat liver cirrhosis, an irreversible disease that may eventually lead to liver cancer development. However, low survival rate of the BM-MSCs leading to unsatisfactory efficacy remains a major concern. Gender differences have been suggested in BM-MSCs therapeutic application, but the effect of the androgen receptor (AR), a key factor in male sexual phenotype, in this application is not clear. Using two liver cirrhosis mouse models induced by CCl4 or thioacetamide, we showed that targeting AR in the BM-MSCs improved their self-renewal and migration potentials and increased paracrine effects to exert anti-inflammatory and anti-fibrotic actions to enhance liver repair. Mechanism dissection studies suggested that knocking out AR in BM-MSCs led to improved self-renewal and migration by alteration of the signaling of epidermal growth factor receptor and matrix metalloproteinase 9 and resulted in suppression of infiltrating macrophages and hepatic stellate cell activation through modulation of interleukin (IL)1R/IL1Ra signaling. Therapeutic approaches using either AR/small interfering RNA or the AR degradation enhancer, ASC-J9, to target AR in BM-MSCs all led to increased efficacy for liver repair. CONCLUSION: Targeting AR, a key factor in male sexual phenotype, in BM-MSCs improves transplantation therapeutic efficacy for treating liver fibrosis.


Assuntos
Tetracloreto de Carbono/efeitos adversos , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/cirurgia , Transplante de Células-Tronco Mesenquimais , Receptores Androgênicos/genética , Tioacetamida/efeitos adversos , Animais , Modelos Animais de Doenças , Receptores ErbB/metabolismo , Feminino , Cirrose Hepática/metabolismo , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Knockout , Fenótipo , RNA Interferente Pequeno/farmacologia , Receptores Androgênicos/efeitos dos fármacos , Receptores de Interleucina-1/metabolismo , Transdução de Sinais/fisiologia , Resultado do Tratamento
18.
Alcohol Clin Exp Res (Hoboken) ; 48(1): 88-97, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38206286

RESUMO

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) and alcohol consumption have both increased in recent years, and there is debate as to whether nonheavy alcohol use is safe in MASLD. We analyzed the association between different nonheavy alcohol use patterns and at-risk liver fibrosis among individuals with MASLD. METHODS: We conducted a cross-sectional study of 1072 eligible National Health and Nutrition Examination Survey participants with MASLD who reported nonheavy alcohol consumption. We used vibration-controlled transient elastography to define the primary outcome of at-risk liver fibrosis as >8.2 kPa (stage F2-F4). Multivariable logistic regression models were used to determine the association of different alcohol consumption patterns (average drinks/day, drinking days/week, weekly alcohol intake, type of alcoholic beverage) and at-risk hepatic fibrosis, controlling for demographic/socioeconomic, lifestyle/dietary, and metabolic risk factors. RESULTS: Exclusive liquor or cocktail drinkers had a 5.02-fold odds of at-risk fibrosis (95% CI: 1.15-21.95) compared with non-drinkers when controlling for potential confounders. While consuming an average of 2 drinks/day, ≥3 drinking days/week, or 1-3 drinks/week appeared to have a lower association with at-risk fibrosis when controlling for demographic/socioeconomic risk factors, the association was not present after controlling for lifestyle/dietary and metabolic risk factors. CONCLUSIONS: There is an association between exclusive liquor/cocktail consumption and at-risk liver fibrosis in patients with MASLD who report nonheavy alcohol consumption.

19.
Cancer Lett ; 580: 216493, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37977350

RESUMO

Cholangiocarcinoma (CCA) is resistant to systemic chemotherapies that kill malignant cells mainly through DNA damage responses (DDRs). Recent studies suggest that the involvement of 2-oxoglutarate (2-OG) dependent dioxygenases in DDRs may be associated with chemoresistance in malignancy, but how 2-OG impacts DDRs in CCA chemotherapy remains elusive. We examined serum 2-OG levels in CCA patients before receiving chemotherapy. CCA patients are classified as progressive disease (PD), partial response (PR), and stable disease (SD) after receiving chemotherapy. CCA patients classified as PD showed significantly higher serum 2-OG levels than those defined as SD and PR. Treating CCA cells with 2-OG reduced DDRs. Overexpression of full-length aspartate beta-hydroxylase (ASPH) could mimic the effects of 2-OG on DDRs, suggesting the important role of ASPH in chemoresistance. Indeed, the knockdown of ASPH improved chemotherapy in CCA cells. Targeting ASPH with a specific small molecule inhibitor also enhanced the effects of chemotherapy. Mechanistically, ASPH modulates DDRs by affecting ATM and ATR, two of the major regulators finely controlling DDRs. More importantly, targeting ASPH improved the therapeutic potential of chemotherapy in two preclinical CCA models. Our data suggested the impacts of elevated 2-OG and ASPH on chemoresistance through antagonizing DDRs. Targeting ASPH may enhance DDRs, improving chemotherapy in CCA patients.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Ácido Aspártico/metabolismo , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Ductos Biliares Intra-Hepáticos , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Dano ao DNA , Ácidos Cetoglutáricos , Oxigenases de Função Mista/genética
20.
J Biol Chem ; 287(47): 39954-66, 2012 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-23012352

RESUMO

Androgen receptor (AR) expression surveys found that normal prostate/prostate cancer (PCa) stem/progenitor cells, but not embryonic or mesenchymal stem cells, expressed little AR with high methylation in the AR promoter. Mechanism dissection revealed that the differential methylation pattern in the AR promoter could be due to differential expression of methyltransferases and binding of methylation binding protein to the AR promoter region. The low expression of AR in normal prostate/PCa stem/progenitor cells was reversed after adding 5-aza-2'-deoxycytidine, a demethylating agent, which could then lead to decreased stemness and drive cells into a more differentiated status, suggesting that the methylation in the AR promoter of prostate stem/progenitor cells is critical not only in maintaining the stemness but also critical in protection of cells from differentiation. Furthermore, induced AR expression, via alteration of its methylation pattern, led to suppression of the self-renewal/proliferation of prostate stem/progenitor cells and PCa tumorigenesis in both in vitro assays and in vivo orthotopic xenografted mouse studies. Taken together, these data prove the unique methylation pattern of AR promoter in normal prostate/PCa stem/progenitor cells and the influence of AR on their renewal/proliferation and differentiation. Targeting PCa stem/progenitor cells with alteration of methylated AR promoter status might provide a new potential therapeutic approach to battle PCa because the PCa stem/progenitor cells have high tumorigenicity.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/análogos & derivados , Transformação Celular Neoplásica/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , DNA de Neoplasias/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Neoplasias/biossíntese , Células-Tronco Neoplásicas/metabolismo , Regiões Promotoras Genéticas , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/biossíntese , Animais , Azacitidina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Metilação de DNA/genética , DNA de Neoplasias/genética , Decitabina , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Camundongos , Proteínas de Neoplasias/genética , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Receptores Androgênicos/genética , Transplante Heterólogo
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