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1.
Life Sci ; 236: 116921, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610196

RESUMO

AIMS: To assess the role of glycogen synthase kinase-3ß (GSK3ß) and ß-catenin in the protection of ischemic injury by dexmedetomidine (Dex). MAIN METHODS: Adult male Sprague-Dawley rats were subjected to (middle cerebral artery occlusion, MCAO) for 2 h followed by reperfusion and Dex was administered 30min before MCAO. The neurological deficit score, cerebral infarct size and neuron survival were evaluated at 24 h after reperfusion. The expression of pAKT, pGSK3ß and ß-catenin in the ischemic penumbra was assayed by Western blot at 2 h after reperfusion. KEY FINDINGS: We found that the Dex-induced increment of neuron survival in the ischemic penumbra was diminished by the PI3K inhibitor LY294002 and the ß-catenin inhibitor XAV939, respectively. The increasing expression of pAKT, pGSK3ß and ß-catenin induced by Dex was markedly inhibited by LY294002. And the increasing expression of ß-catenin in nuclei induced by Dex was markedly inhibited by XAV939. At the same time, the GSK3ß inhibitor SB216763 also caused an increment of neuron survival and an increasing expression of pGSK3ß and ß-catenin in the ischemic penumbra. SIGNIFICANCE: Our data suggested that treatment with Dex reduced cerebral injury in rats exposed to cerebral ischemia-reperfusion (I/R) by the activation of the PI3K/AKT/GSK3ß pathways as well the activation of downstream Wnt/ß-catenin pathway. And the Wnt/ß-catenin pathway may play an important role in the protection against cerebral ischemia/reperfusion injury in rats.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Dexmedetomidina/farmacologia , Infarto da Artéria Cerebral Média/prevenção & controle , Traumatismo por Reperfusão/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Apoptose , Infarto da Artéria Cerebral Média/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Proteínas Wnt/genética , beta Catenina/genética
2.
Zhongguo Zhong Yao Za Zhi ; 44(14): 3107-3115, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31602860

RESUMO

The aim of this paper was to investigate the effects of curcumin on the proliferation,migration,invasion and apoptosis of human gastric cancer cells and to explore the potential mechanisms. SGC7901,MKN45 and NCI N87 cells lines were cultured under different concentrations of curcumin( 2. 5,5,10,20,40,80 and 160 µmol·L~(-1)) at different time points( 12,24,48 and 72 h),and the effect of curcumin on cell proliferation was detected by CCK-8 assay. The migration and invasiveness of cells were determined by wound healing and Transwell assays,the apoptosis rate was assessed by flow cytometry,the expression of N-cadherin,E-cadherin,snail1,Wnt3 a,p-ß-catenin,p-LRP6,Bcl-2 and Bax were detected by Western blot,and the enzymatic activity of caspase-3,caspase-8 and caspase-9 was evaluated via caspase kit. RESULTS:: indicated that the proliferation of MKN45 cells was significantly inhibited by curcumin in a dose-and time-dependent manner( IC50= 21. 93 µmol·L~(-1)). Moreover,curcumin could inhibit the migration and invasion of MKN45 cells,downregulate the expression of N-cadherin,snail1,Wnt3 a,p-ß-catenin,p-LRP6 and Bcl-2,and upregulate the expression of E-cadherin and Bax,it could increase the activity of caspase-3,caspase-8,caspase-9 and induce apoptosis as well. The potential mechanism is through inhibiting the Wnt3 a/ß-catenin/EMT pathway,regulating Bcl-2 signaling and caspase pathway,which might provide new potential strategies for gastric cancer treatment.


Assuntos
Curcumina/farmacologia , Neoplasias Gástricas/patologia , Via de Sinalização Wnt , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Humanos , Neoplasias Gástricas/tratamento farmacológico , Proteína Wnt3A/metabolismo , beta Catenina/metabolismo
3.
Postepy Biochem ; 65(3): 183-192, 2019 10 01.
Artigo em Polonês | MEDLINE | ID: mdl-31643165

RESUMO

The canonical Wnt pathway is related to regulation of embryogenesis, cell differentiation and proliferation. Various proteins are necessary for proper signal transduction and ß-catenin serves as the main mediator. In off-state of the Wnt pathway ß-catenin undergoes proteasomal degradation, while in on-state increase of cytoplasmic concentration of ß-catenin occurs followed by ß-catenin translocation into the cell nucleus. Interaction between ß-catenin and TCF/LEF transcription factors activates the expression of over hundred target genes of the Wnt pathway. Highly active Wnt signaling is observed in many cancers, including head and neck squamous cell carcinomas. Knowledge of the functional structure of the canonical Wnt pathway enables search of therapeutic molecular targets to effectively inhibit transcriptional activity of ß-catenin in cancer cells.


Assuntos
Via de Sinalização Wnt , beta Catenina/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Fatores de Transcrição TCF/metabolismo , Via de Sinalização Wnt/genética
4.
J Agric Food Chem ; 67(41): 11464-11473, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31532211

RESUMO

The intestinal epithelium is derived from intestinal stem cells (ISCs) and has direct contact with nutrients and toxins. However, whether methionine (Met) or a methionine hydroxyl analogue (2-hydroxy-4-(methylthio)butanoic acid (HMB)) can alleviate deoxynivalenol (DON)-induced intestinal injury remains unknown. Mice were treated orally with Met or HMB on days 1-11 and with DON on days 4-8. On day 12, the mice were sacrificed, and the jejunum was collected for crypt isolation and culture. Mouse enteroids were treated with DON and Met or HMB ex vivo. The results showed that Met and HMB increased the average daily feed intake and average daily gain of the mice. Met and HMB also improved the jejunal structure and barrier integrity and promoted ISC expansion, as indicated by the increased enteroid formation efficiency and area, under DON-induced injury conditions. In addition, DON-induced decreases in ISC activity were rescued Wnt/ß-catenin signaling reactivation by Met or HMB in vivo and ex vivo. Collectively, our findings reveal that Met and HMB alleviated DON-induced intestinal injury by improving ISC expansion and reactivating Wnt/ß-catenin signaling. Our study thus provides a nutritional intervention for intestinal diseases involving Wnt/ß-catenin signaling.


Assuntos
Enteropatias/tratamento farmacológico , Metionina/análogos & derivados , Metionina/administração & dosagem , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos , Tricotecenos/toxicidade , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Humanos , Enteropatias/genética , Enteropatias/metabolismo , Enteropatias/fisiopatologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/lesões , Mucosa Intestinal/metabolismo , Masculino , Camundongos , Células-Tronco/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
5.
Life Sci ; 235: 116798, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472149

RESUMO

Lung cancer is the leading cause for cancer death due to refractory nature to current treatment strategies, understanding the regulatory mechanism of therapy resistance of lung cancer is important for lung cancer therapy. Here, we aimed to study the role of SHCBP1 in lung cancer cisplatin resistance, we found SHCBP1 was upregulated in lung cancer tissues and cells, patients with high SHCBP1 had poor prognosis. SHC binding and spindle associated 1 (SHCBP1) overexpression promoted cisplatin induced apoptosis resistance, migration and invasion determined by apoptosis assay and transwell assay with or without Matrigel, while SHCBP1 knockdown inhibited cisplatin induced apoptosis resistance, migration and invasion. Wnt pathway promoted lung cancer progression, we found SHCBP1 activated Wnt pathway, characterized by promoting ß-catenin nuclear translocation. Inhibition of Wnt pathway in SHCBP1 overexpression cells reversed the effect of SHCBP1 overexpression, confirming SHCBP1 promoted lung cancer progression through activating Wnt pathway. We also found SHCBP1 expression was positively corrected with Wnt pathway activity in lung cancer samples. In summary, we found SHCBP1 promoted cisplatin induced apoptosis resistance, migration and invasion through activating Wnt pathway, providing a potential target for lung cancer therapy.


Assuntos
Apoptose , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/patologia , Proteínas Adaptadoras da Sinalização Shc/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Invasividade Neoplásica , Prognóstico , Proteínas Adaptadoras da Sinalização Shc/genética , Taxa de Sobrevida , Proteínas Wnt/genética , Via de Sinalização Wnt , beta Catenina/genética
6.
J Agric Food Chem ; 67(37): 10285-10295, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31443611

RESUMO

Fluoride (F) is capable of promoting abnormal proliferation and differentiation in primary cultured mouse osteoblasts (OB cells), although the underlying mechanism responsible remains rare. This study aimed to explore the roles of wingless and INT-1 (Wnt) signaling pathways and screen appropriate doses of calcium (Ca2+) to alleviate the sodium fluoride (NaF)-induced OB cell toxicity. For this, we evaluated the effect of dickkopf-related protein 1 (DKK1) and Ca2+ on mRNA levels of wingless/integrated 3a (Wnt3a), low-density lipoprotein receptor-related protein 5 (LRP5), dishevelled 1 (Dv1), glycogen synthase kinase 3ß (GSK3ß), ß-catenin, lymphoid enhancer binding factor 1 (LEF1), and cellular myelocytomatosis oncogene (cMYC), as well as Ccnd1 (Cyclin D1) in OB cells challenged with 10-6 mol/L NaF for 24 h. The demonstrated data showed that F significantly increased the OB cell proliferation rate. Ectogenic 0.5 mg/L DKK1 significantly inhibited the proliferation of OB cells induced by F. The mRNA expression levels of Wnt3a, LRP5, Dv1, LEF1, ß-catenin, cMYC, and Ccnd1 were significantly increased in the F group, while significantly decreased in the 10-6 mol/L NaF + 0.5 mg/L DKK1 (FY) group. The mRNA expression levels of Wnt3a, LRP5, ß-catenin, and cMYC were significantly decreased in the 10-6 mol/L NaF + 2 mmol/L CaCl2 (F+CaII) group. The protein expression levels of Wnt3a, Cyclin D1, cMYC, and ß-catenin were significantly increased in the F group, whereas they were decreased in the F+CaII group. However, the mRNA and protein expression levels of GSK3ß were significantly decreased in the F group while significantly increased in the F+CaII group. In summary, F activated the canonical Wnt/ß-catenin pathway and changed the related gene expression and ß-catenin protein location in OB cells, promoting cell proliferation. Ca2+ supplementation (2 mmol/L) reversed the expression levels of genes and proteins related to the canonical Wnt/ß-catenin pathway.


Assuntos
Cálcio/metabolismo , Fluoretos/efeitos adversos , Osteoblastos/efeitos dos fármacos , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Suplementos Nutricionais/análise , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Camundongos , Osteoblastos/classificação , Osteoblastos/metabolismo , Proteínas Wnt/genética , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/genética
7.
APMIS ; 127(11): 699-709, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31403731

RESUMO

We aimed to assess (1)-whether nuclear ß-catenin is a marker of endometrial precancer, and (2)-the diagnostic accuracy of ß-catenin immunohistochemistry in the differential diagnosis between benign and premalignant endometrial hyperplasia (EH), defining criteria for its use. Electronic databases were searched for studies evaluating ß-catenin immunohistochemistry in normal endometrium (NE), benign and/or premalignant EH, and endometrioid carcinoma (EC). Odds ratio (OR; p < 0.05), sensitivity, specificity, diagnostic OR (DOR), positive and negative likelihood ratios (LR+, LR-) were calculated. Subgroup analyses were based on the classification system used (WHO or EIN) and criteria to define aberrant ß-catenin expression (only nuclear or cytoplasmic/nuclear). Twelve studies with 1510 specimens were included. Nuclear ß-catenin rate significantly increased from NE to benign EH (OR = 26.01; p = 0.0002, only in WHO subgroup), and from benign EH to premalignant EH (OR = 3.89; p = 0.0002; more markedly in EIN subgroup), but not from premalignant EH to EC (OR = 0.78; p = 0.29). Nuclear ß-catenin accuracy was very low in WHO subgroup (sensitivity = 0.40, specificity = 0.76, LR+ = 1.85, LR- = 0.72; DOR = 2.89) and moderate in EIN subgroup (sensitivity = 0.19, specificity = 1.00, LR+ = 14.80, LR- = 0.83; DOR = 18.14). Cytoplasmic/nuclear ß-catenin accuracy was absent in WHO subgroup (sensitivity = 0.45, specificity = 0.54, LR+ = 1.01, LR- = 1.01; DOR = 0.99) and low in EIN subgroup (sensitivity = 0.57, specificity = 0.86, LR+ = 3.63, LR- = 0.51; DOR = 8.30). Considering nuclear expression and using EIN system, ß-catenin immunohistochemistry might be reliable as rule-in test for diagnosis of endometrial precancer, with perfect specificity and moderate overall accuracy.


Assuntos
Biomarcadores/metabolismo , Núcleo Celular/metabolismo , Hiperplasia Endometrial/metabolismo , Lesões Pré-Cancerosas/metabolismo , beta Catenina/metabolismo , Núcleo Celular/genética , Hiperplasia Endometrial/genética , Hiperplasia Endometrial/patologia , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Feminino , Humanos , Imuno-Histoquímica , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/patologia , beta Catenina/genética
8.
Oncol Rep ; 42(4): 1451-1458, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31364732

RESUMO

Epithelial­mesenchymal transition (EMT) is closely related to tumor metastasis, and offers insight into novel strategies for cancer treatment. HMQ­T­F2 (F2) is a taspine derivative, which has excellent anticancer activity in human cervical cancer. The present study aimed to evaluate the effect of F2 on in vitro migration of HeLa cells. The present data demonstrated that F2 inhibited migration of HeLa cells by negatively regulating the Wnt signaling pathway and reversing EMT. F2 not only mediated Frizzled8, p­LRP6 and LRP6 expression, but also downregulated the phosphorylation of GSK3ß, and concurrently decreased the nucleus protein expression of MMP2, MMP3, MMP7, MMP9, and c­Myc. In addition, the expression of N­cadherin, vimentin, Snail and HIF­1α were downregulated and that of E­cadherin was upregulated after F2 treatment. F2 was also associated with the downregulation of the PI3K/Akt/mTOR signaling pathways. Notably, F2 induced HeLa cell accumulation at the S phase and cell apoptosis. These results provide evidence that F2 inhibits HeLa cell migration, proliferation and promotes apoptosis. It also reverses EMT, potentially via the PI3K/Akt signaling pathway. Therefore, F2 may be a potential therapeutic reagent against cervical cancer.


Assuntos
Alcaloides/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Alcaloides/química , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Células HeLa , Humanos , Fase S/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Neoplasias do Colo do Útero/patologia , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/metabolismo
9.
Cancer Sci ; 110(10): 3110-3121, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385398

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancies and the fourth leading cause of cancer-related death worldwide. Our previous study showed that EYA4 functioned by suppressing growth of HCC tumor cells, but its molecular mechanism is still not elucidated. Based on the results of gene microassay, EYA4 was inversely correlated with MYCBP and was verified in human HCC tissues by immunohistochemistry and western blot. Overexpressed and KO EYA4 in human HCC cell lines confirmed the negative correlation between EYA4 and MYCBP by qRT-PCR and western blot. Transfected siRNA of MYCBP in EYA4 overexpressed cells and overexpressed MYCBP in EYA4 KO cells could efficiently rescue the proliferation and G2/M arrest effects of EYA4 on HCC cells. Mechanistically, armed with serine/threonine-specific protein phosphatase activity, EYA4 reduced nuclear translocation of ß-catenin by dephosphorylating ß-catenin at Ser552, thereby suppressing the transcription of MYCBP which was induced by ß-catenin/LEF1 binding to the promoter of MYCBP. Clinically, HCC patients with highly expressed EYA4 and poorly expressed MYCBP had significantly longer disease-free survival and overall survival than HCC patients with poorly expressed EYA4 and highly expressed MYCBP. In conclusion, EYA4 suppressed HCC tumor cell growth by repressing MYCBP by dephosphorylating ß-catenin S552. EYA4 combined with MYCBP could be potential prognostic biomarkers in HCC.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA/genética , Neoplasias Hepáticas/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , beta Catenina/metabolismo , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Proliferação de Células , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Serina/metabolismo , Análise de Sobrevida , Fatores de Transcrição/metabolismo , Transcrição Genética , beta Catenina/química
10.
Int J Nanomedicine ; 14: 5697-5711, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413570

RESUMO

Purpose: Calcium (Ca) and magnesium (Mg) ions have been used as promising bioactive ions in the surface chemistry modification of titanium (Ti) bone implants to increase bone regeneration capacity. However, it is not clear which (Ca or Mg) plays the more important role in the early osteogenic differentiation of mesenchymal stem cells (MSCs) when applied to the surface of commercially available microstructured Ti implants. This study investigated the relative effect of these two ions on the early osteogenic functionality of primary mouse bone marrow MSCs in order to obtain insights into the surface design of Ti implants with enhanced early osteogenic capacity. Methods and results: Wet chemical treatment was performed to modify a microrough Ti implant surface using Ca or Mg ions. Both the Ca and Mg-incorporated surfaces accelerated early cellular events and the subsequent osteogenic differentiation of MSCs compared with an unmodified microrough Ti surface. Surface Mg modification exhibited a more potent osteoblast differentiation-promoting effect than the Ca modification. Surface Mg incorporation markedly inhibited the phosphorylation of ß-catenin. Conclusion: These results indicate that alteration of the surface chemistry of microstructured Ti implants by wet chemical treatment with Mg ions exerts a more effect on promoting the early osteogenic differentiation of MSCs than Ca ions by enhancing early cellular functions, including focal adhesion development and stabilization of intracellular ß-catenin.


Assuntos
Cálcio/farmacologia , Magnésio/farmacologia , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Titânio/farmacologia , Animais , Cátions Bivalentes/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Adesões Focais/efeitos dos fármacos , Íons , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Propriedades de Superfície , Água/química , Difração de Raios X , beta Catenina/metabolismo
11.
Cancer Sci ; 110(9): 2794-2805, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31336010

RESUMO

SALL4 is overexpressed in many cancers and is found to be involved in tumorigenesis and tumor progression. However, the function of SALL4 in cervical cancer remains unknown. Here, we showed that the expression of SALL4 was gradually increased from normal cervical tissue to high-grade squamous intraepithelial lesions and then to squamous cervical carcinoma. SALL4 was upregulated or downregulated in cervical cancer cells by stably transfecting a SALL4-expressing plasmid or a shRNA plasmid targeting SALL4, respectively. In vitro, cell growth curves and MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide) assays showed that SALL4 promoted the cell proliferation of cervical cancer cells. In vivo, xenograft experiments verified that SALL4 enhanced the tumor formation of cervical cancer cells in female BALB/c Nude mice. Cell cycle analysis by fluorescence-activated cell sorting found that SALL4 accelerates cell cycle transition from the G0 /G1 phase to the S phase. TOP/FOP-Flash reporter assay revealed that SALL4 significantly upregulates the activity of Wnt/ß-catenin pathway. Western blotting showed that the expression levels of ß-catenin and important downstream genes, including c-Myc and cyclin D1, were increased by SALL4 in cervical cancer cells. Furthermore, dual-luciferase reporter and chromatin immunoprecipitation assays confirmed that SALL4 transcriptionally activated CTNNB1 by physically interacting with its promoters. Taken together, The results of this study demonstrated that SALL4 may promote cell proliferation and tumor formation of cervical cancer cells by upregulating the activity of the Wnt/ß-catenin signaling pathway by directly binding to the CTNNB1 promoter and trans-activating CTNNB1.


Assuntos
Carcinoma de Células Escamosas/genética , Transformação Celular Neoplásica/genética , Lesões Intraepiteliais Escamosas Cervicais/patologia , Fatores de Transcrição/metabolismo , Neoplasias do Colo do Útero/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Colo do Útero/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Regiões Promotoras Genéticas/genética , RNA Interferente Pequeno/metabolismo , Lesões Intraepiteliais Escamosas Cervicais/genética , Fatores de Transcrição/genética , Regulação para Cima , Neoplasias do Colo do Útero/patologia , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
12.
Life Sci ; 232: 116626, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276688

RESUMO

PURPOSE: The aim of this study was to investigate the role of the suppressor of activator protein-1 regulated by interferon (SARI), in the development and progression of prostate cancer. METHODS: Sixty-seven prostate cancer tissue specimens and 20 benign prostatic hyperplasia specimens were used to investigate the correlation between SARI expression and clinicopathologic parameters. Immunohistochemistry was used to detect the SARI and E-cadherin protein expression in the prostate cancer and benign prostatic hyperplasia specimens, and their correlation was established. Quantitative PCR (qPCR) was used to determine the SARI mRNA expression in a normal prostate cell line (RWPE-1) and prostate cancer cell lines (LNCaP and PC3). Western blotting was used to detect the SARI protein expression in the RWPE-1, LNCaP, and PC3 cell lines. RESULTS: SARI protein expression did not correlate with the prostate cancer patients' age or serum Prostate-Specific Antigen value but did show a correlation with the tumor stage of prostate cancer and Gleason score. SARI and E-cadherin expression in the prostate cancer tissue was significantly lower than in the benign prostatic hyperplasia specimens, suggesting a positive correlation between the SARI and E-cadherin expression. SARI mRNA and protein were highly expressed in RWPE-1, the normal prostate cell line, but SARI mRNA and protein expression were reduced in the prostate cancer cell lines, LNCaP and PC3. Significant differences in the expression were found between the prostate cancer cell lines and the normal prostate cell line. CONCLUSION: In this study, high SARI expression was found to be negatively correlated with the development and progression of prostate cancer.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Neoplasias da Próstata/genética , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Idoso , Western Blotting , Caderinas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Imuno-Histoquímica , Interferons/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Fosfatidilinositol 3-Quinases/metabolismo , Próstata/citologia , Próstata/patologia , Hiperplasia Prostática/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , Fator de Transcrição AP-1/metabolismo , beta Catenina/metabolismo
13.
Gene ; 712: 143958, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31278963

RESUMO

The Wnt signaling pathway has been identified for its function in carcinogenesis and embryonic development. It is known to play a vital role in the initiation and development of colorectal cancer (CRC). Therefore, it is of great importance for CRC research to illuminate the mechanisms which regulate Wnt pathway activity. Here, we intended to examine the effect of hsa-miR-942 (miR-942) on the Wnt signaling activity, cell cycle progression, and its expression in CRC tissues. RT-qPCR results indicated that miR-942 is significantly upregulated in colorectal cancer. Then, overexpression of miR-942 promoted, whereas its inhibition decreased the Wnt signaling activity, detected by RT-qPCR and Top/Fop flash assay. Inhibition of Wnt signaling by using PNU-74654 or IWP-2 small molecules indicated that miR-942 applies its effect to the ß-catenin degradation complex level. Then, RT-qPCR and dual luciferase assay showed that miR-942 upregulated Wnt signaling through direct targeting of APC, which is a tumor suppressor in Wnt signaling pathway. Furthermore, the western blotting analysis indicated that ß.catenin, as a main member of Wnt signaling pathway is upregulated following the overexpression of miR-942. Finally, miR-942 overexpression resulted in cell cycle progression in SW480 cells. Taken together, our findings established an oncogenic role for miR-942 in CRC and indicated that this miRNA might be a crucial target for CRC therapy.


Assuntos
Neoplasias Colorretais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Via de Sinalização Wnt , Regiões 3' não Traduzidas , Carcinogênese/genética , Ciclo Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Biologia Computacional , Ciclina D1/metabolismo , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Luciferases/metabolismo , Masculino , Plasmídeos/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Interferência de RNA , RNA Longo não Codificante/genética , Transdução de Sinais , Regulação para Cima , beta Catenina/metabolismo
14.
Life Sci ; 232: 116617, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260685

RESUMO

AIM: To investigate the effects and underlying mechanisms of taxifolin on proliferation, migration and invasion of highly aggressive breast cancer in vitro and in vivo. MAIN METHODS: The antineoplastic activity of taxifolin was evaluated in MDA-MB-231 and 4 T1 cells by crystal violet assay and colony formation assay. The effects of taxifolin on migration and invasion were determined by wound healing assay and Transwell assay, respectively. mRNA and protein expression of genes were assayed respectively with qRT-PCR and western blot, and the protein expression and location was also detected by immunofluorescence and immunohistochemistry. ß-catenin overexpression was performed with adenovirus infection. The effects of taxifolin on growth and metastasis of breast cancer in vivo were investigated in BALB/c mice bearing 4T1 xenografts. KEY FINDINGS: We found that taxifolin had the potential to inhibit proliferation, migration and invasion of highly aggressive breast cancer cells in a dose-dependent manner. In addition, taxifolin promoted the MET process, the reversed process of EMT, as evaluated by EMT markers and EMT-transcriptional factors in breast cancer cell lines. Meanwhile, the protein and mRNA expressions of ß-catenin were dose-dependently downregulated by taxifolin, and overexpression of ß-catenin by adenoviruses abrogated these beneficial effects of taxifolin above-mentioned. Furthermore, within a 4T1 xenograft mouse model, taxifolin markedly inhibited the growth of primary tumors and reduced lung metastasis of breast cancer. SIGNIFICANCE: Our findings provide a theoretical foundation for the possibility of taxifolin used as a promising agent in the clinical treatment of highly aggressive breast cancer patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Quercetina/análogos & derivados , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Quercetina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/metabolismo
15.
Int Arch Allergy Immunol ; 180(2): 79-90, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31340215

RESUMO

BACKGROUND: In this study, we examined whether RORA (retinoic acid receptor-related orphan receptor alpha) was capable of alleviating the progression of allergic rhinitis (AR). METHODS: In order to elucidate the possible effects of RORA and the regulatory mechanism between RORA and the Wnt/ß-catenin signaling pathway, mouse AR models were established and treated with RORA vector, siRNA against RORA, or the Wnt/ß-catenin pathway inhibitor WIF-1. Subsequently, the serum levels of inflammatory cytokines (IgE, INF-γ, IL-1ß, IL-4, and IL-17), red blood cell (RBC) immune adhesion function, the levels of RORA, ß-catenin, and GSK3ß, as well as the extent of ß-catenin and GSK-3ß phosphorylation were evaluated and measured. RESULTS: The OVA-induced AR mouse model exhibited obvious nasal mucosal injury and inflammatory cell infiltration. RORA overexpression or the inactivation of the Wnt/ß-catenin signaling pathway was uncovered as a way to ameliorate nasal mucosal injury and eosinophil infiltration of the OVA-induced AR mouse model. On the other hand, it reduced the number of eosinophils and mast cells, which also resulted in downregulated expression of IgE, INF-γ, IL-1ß, IL-4, IL-17, ß-catenin, and GSK-3ß. Moreover, this led to a decreased extent of ß-catenin and GSK-3ß phosphorylation, while the rates of C3b receptor rosette and Ic rosette were elevated. CONCLUSION: Taken together, the key findings provided evidence suggesting that the elevated RORA could potentially alleviate nasal mucosal injury and simultaneously enhance RBC immune adhesion function through the inhibition of the Wnt/ß-catenin signaling pathway activation in an OVA-induced AR mouse model. This emphasizes a novel therapeutic target for the treatment of AR.


Assuntos
Eritrócitos/imunologia , Mucosa Nasal/lesões , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Rinite Alérgica/imunologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Animais , Adesão Celular/fisiologia , Modelos Animais de Doenças , Eosinófilos/imunologia , Proteínas da Matriz Extracelular/metabolismo , Reação de Imunoaderência , Imunoglobulina E/sangue , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Interferon gama/sangue , Interleucina-17/sangue , Interleucina-1beta/sangue , Interleucina-4/sangue , Masculino , Mastócitos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Interferência de RNA , RNA Citoplasmático Pequeno/genética , Rinite Alérgica/prevenção & controle , Via de Sinalização Wnt , beta Catenina/sangue
16.
Cell Prolif ; 52(5): e12664, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31343104

RESUMO

OBJECTIVES: Low back pain becomes a common orthopaedic disease today. It is mainly induced by the degeneration of the intervertebral disc. In this study, we tried to reveal the pathogenesis of the degeneration and the relative therapeutic strategy, which are still elusive. MATERIALS AND METHODS: We collected 15 degenerative intervertebral tissues and five healthy donors. Nucleus pulposus and annulus fibrosus cells were subcultured. miR-640 expression was determined by qPCR. Computer analysis and luciferase reporter assay were used to confirm miR-640 target genes. Immunohistochemical and immunocytochemical staining was used to trace the proinflammatory cytokines and key transductor of signalling pathways. We also used ß-galactosidase staining, flow cytometry, and cell viability assay to monitor the degenerative index. RESULTS: miR-640 overexpressed in patients derived degenerative nucleus pulposus tissues and cells. The inflammatory environment promoted miR-640 expression via NF-κB signalling pathway. In addition, miR-640 targeted to LRP1 and enhances NF-κB signal activity, which built a positive feedback loop. miR-640 inhibited the expression of ß-catenin and EP300, therefore, restrained WNT signal and induced the degeneration in nucleus pulposus cells. miR-640 inhibitor treatment exhibited the effects of anti-inflammation, reverse WNT signalling pathway exhaustion, and remission of degenerative characteristics in vitro. CONCLUSIONS: miR-640 plays an important role in the degeneration of intervertebral disc and the relative inflammatory microenvironment. It is a promising potential therapeutic target for the low back pain biotherapy.


Assuntos
Degeneração do Disco Intervertebral/patologia , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Proteínas Wnt/metabolismo , Adolescente , Adulto , Anel Fibroso/citologia , Anel Fibroso/metabolismo , Antagomirs/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Proteína p300 Associada a E1A/metabolismo , Humanos , Interleucina-1beta/metabolismo , Degeneração do Disco Intervertebral/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/química , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Pessoa de Meia-Idade , Núcleo Pulposo/citologia , Núcleo Pulposo/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Adulto Jovem , beta Catenina/metabolismo
17.
Int J Nanomedicine ; 14: 4229-4245, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239677

RESUMO

Purpose: Gene therapies via Noggin small interfering (si)RNA (siNoggin) and bone morphogenetic protein (BMP)-2 plasmid DNA (pBMP-2) may be promising strategies for bone repair/regeneration, but their ideal delivery vectors, efficacy difference, and underlying mechanisms have not been explored, so these issues were probed here. Methods: This study used lipopolysaccharide-amine nanopolymersomes (LNPs), an efficient cytosolic delivery vector developed by the research team, to mediate siNoggin and pBMP-2 to transfect MC3T3-E1 cells, respectively. The cytotoxicity, cell uptake, and gene knockdown efficiency of siNoggin-loaded LNPs (LNPs/siNoggin) were studied, then the osteogenic-differentiation efficacy of MC3T3-E1 cells treated by LNPs/pBMP-2 and LNPs/siNoggin, respectively, were compared by measuring the expression of osteogenesis-related genes and proteins, alkaline phosphatase (ALP) activity, and mineralization of the extracellular matrix at all osteogenic stages. Finally, the possible signaling pathways of the two treatments were explored. Results: LNPs delivered siNoggin into cells efficiently to silence 50% of Noggin expression without obvious cytotoxicity. LNPs/siNoggin and LNPs/pBMP-2 enhanced the osteogenic differentiation of MC3T3 E1 cells, but LNPs/siNoggin was better than LNPs/pBMP-2. BMP/Mothers against decapentaplegic homolog (Smad) and glycogen synthase kinase (GSK)-3ß/ß-catenin signaling pathways appeared to be involved in osteogenic differentiation induced by LNPs/siNoggin, but GSK-3ß/ß-catenin was not stimulated upon LNPs/pBMP-2 treatment. Conclusion: LNPs are safe and efficient delivery vectors for DNA and RNA, which may find wide applications in gene therapy. siNoggin treatment may be a more efficient strategy to enhance osteogenic differentiation than pBMP-2 treatment. LNPs loaded with siNoggin and/or pBMP-2 may provide new opportunities for the repair and regeneration of bone.


Assuntos
Proteína Morfogenética Óssea 2/metabolismo , Proteínas de Transporte/metabolismo , Diferenciação Celular , Lipopolissacarídeos/farmacologia , Nanopartículas/química , Osteogênese , Polímeros/química , RNA Interferente Pequeno/administração & dosagem , Fosfatase Alcalina/metabolismo , Aminas/química , Animais , Diferenciação Celular/genética , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Matriz Extracelular/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Camundongos , Minerais/química , Nanopartículas/toxicidade , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Plasmídeos/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Transfecção , beta Catenina/metabolismo
18.
Gastroenterology ; 157(3): 793-806.e14, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31170413

RESUMO

BACKGROUND & AIMS: The role of aryl hydrocarbon receptor (AhR) in liver fibrosis is controversial because loss and gain of AhR activity both lead to liver fibrosis. The goal of this study was to investigate how the expression of AhR by different liver cell types, hepatic stellate cells (HSCs) in particular, affects liver fibrosis in mice. METHODS: We studied the effects of AhR on primary mouse and human HSCs, measuring their activation and stimulation of fibrogenesis using RNA-sequencing analysis. C57BL/6J mice were given the AhR agonists 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 2-(1'H-indole-3'-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE); were given carbon tetrachloride (CCl4); or underwent bile duct ligation. We also performed studies in mice with disruption of Ahr specifically in HSCs, hepatocytes, or Kupffer cells. Liver tissues were collected from mice and analyzed by histology, immunohistochemistry, and immunoblotting. RESULTS: AhR was expressed at high levels in quiescent HSCs, but the expression decreased with HSC activation. Activation of HSCs from AhR-knockout mice was accelerated compared with HSCs from wild-type mice. In contrast, TCDD or ITE inhibited spontaneous and transforming growth factor ß-induced activation of HSCs. Mice with disruption of Ahr in HSCs, but not hepatocytes or Kupffer cells, developed more severe fibrosis after administration of CCl4 or bile duct ligation. C57BL/6J mice given ITE did not develop CCl4-induced liver fibrosis, whereas mice without HSC AhR given ITE did develop CCl4-induced liver fibrosis. In studies of mouse and human HSCs, we found that AhR prevents transforming growth factor ß-induced fibrogenesis by disrupting the interaction of Smad3 with ß-catenin, which prevents the expression of genes that mediate fibrogenesis. CONCLUSIONS: In studies of human and mouse HSCs, we found that AhR prevents HSC activation and expression of genes required for liver fibrogenesis. Development of nontoxic AhR agonists or strategies to activate AhR signaling in HSCs might be developed to prevent or treat liver fibrosis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Senescência Celular , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Células Estreladas do Fígado/metabolismo , Cirrose Hepática Experimental/prevenção & controle , Fígado/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proliferação de Células , Células Cultivadas , Senescência Celular/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Indóis/farmacologia , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/deficiência , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Proteína Smad3/metabolismo , Tiazóis/farmacologia , beta Catenina/metabolismo
19.
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
20.
Food Chem Toxicol ; 131: 110550, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31163223

RESUMO

Aberrant activation of ß-catenin-response transcription (CRT) is a well-recognized characteristic of colorectal and liver cancers and thus a potential therapeutic target for these malignancies. Broussonetia papyrifera (paper mulberry) has been used as a herbal medicine to treat various diseases. Using a sensitive cell-based screening system, we identified broussochalcone A (BCA), a prenylated chalcone isolated from Broussonetia papyrifera, as an antagonist of CRT. BCA accelerated the turnover of intracellular ß-catenin that was accompanied by its N-terminal phosphorylation at Ser33/37/Thr41 residues, marking it for ubiquitin-dependent proteasomal degradation. Pharmacological inhibition of glycogen synthase kinase-3ß could not abrogate BCA-mediated degradation of ß-catenin. BCA decreased the intracellular ß-catenin levels in colon and liver cancer cells with mutations in ß-catenin, adenomatous polyposis coli, and Axin. BCA repressed the expressions of cyclin D1, c-Myc, and Axin2, which are ß-catenin/T-cell factor-dependent genes, and thus decreased the viability of colon and liver cancer cell. Moreover, apoptosis was elicited by BCA, as indicated by the increase in the population of Annexin V-FITC positive cells and caspase-3/7 activities in colon and liver cancer cells. These findings indicate that BCA exerts its cytotoxic effects by promoting phosphorylation/ubiquitin-dependent degradation of ß-catenin and may potentially serve as a chemopreventive agent for colonrectal and liver cancers.


Assuntos
Antineoplásicos/farmacologia , Chalconas/farmacologia , Resorcinóis/farmacologia , beta Catenina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Fosforilação/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/efeitos dos fármacos , Serina/química , Treonina/química , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/química , beta Catenina/genética
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