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2.
Adv Sci (Weinh) ; 10(35): e2305550, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37828611

RESUMO

Effective treatment for metastasis, a leading cause of cancer-associated death, is still lacking. To seed on a distal organ, disseminated cancer cells (DCCs) must adapt to the local tissue microenvironment. However, it remains elusive how DCCs respond the pro-metastatic niche signals. Here, systemic motif-enrichment identified myocyte enhancer factor 2D (MEF2D) as a critical sensor of niche signals to regulate DCCs adhesion and colonization, leading to intrahepatic metastasis and recurrence of liver cancer. In this context, MEF2D transactivates Itgb1 (coding ß1-integrin) and Itgb4 (coding ß4-integrin) to execute temporally unique functions, where ITGB1 recognizes extracellular matrix for early seeding, and ITGB4 acts as a novel sensor of neutrophil extracellular traps-DNA (NETs-DNA) for subsequent chemotaxis and colonization. In turn, an integrin-FAK circuit promotes a phosphorylation-dependent USP14-orchastrated deubiquitination switch to stabilize MEF2D via circumventing degradation by the E3-ubiquitin-ligase MDM2. Clinically, the USP14(pS432)-MEF2D-ITGB1/4 feedback loop is often hyper-active and indicative of inferior outcomes in human malignancies, while its blockade abrogated intrahepatic metastasis of DCCs. Together, DCCs exploit a deubiquitination-dependent switch on MEF2D to integrate niche signals in the liver mesenchyme, thereby amplifying the pro-metastatic integrin-FAK signaling. Disruption of this feedback loop is clinically applicable with fast-track potential to block microenvironmental cues driving metastasis.


Assuntos
Neoplasias Hepáticas , Ubiquitina , Humanos , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Integrinas , DNA , Microambiente Tumoral , Ubiquitina Tiolesterase
4.
Adv Sci (Weinh) ; 10(4): e2204808, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36479819

RESUMO

Lactate, a characteristic metabolite of the tumor microenvironment (TME), drives immunosuppression and promotes tumor progression. Material-engineered strategies for intratumoral lactate modulations demonstrate their promise for tumor immunotherapy. However, understanding of the inherent interconnections of material-enabled lactate regulation, metabolism, and immunity in the TME is scarce. To address this issue, urchin-like catalysts of the encapsulated Gd-doped CeO2 , syrosingopine, and lactate oxidase are used in ZIF-8 (USL, where U, S, and L represent the urchin-like Gd-doped CeO2 @ZIF-8, syrosingopine, and lactate oxidase, respectively) and orthotopic tumor models. The instructive relationships of intratumoral lactate depletion, metabolic reprogramming, and immune activation for catalytic immunotherapy of tumors is illustrated. The catalysts efficiently oxidize intratumoral lactate and significantly promote tumor cell apoptosis by in situ-generated ·OH, thereby reducing glucose supply and inducing mitochondrial damage via lactate depletion, thus reprogramming glycometabolism. Subsequently, such catalytic metabolic reprogramming evokes both local and systemic antitumor immunity by activating M1-polarizaed macrophages and CD8+ T cells, leading to potent antitumor immunity. This study provides valuable mechanistic insights into material-interfered tumor therapy through intratumoral lactate depletion and consequential connection with metabolic reprogramming and immunity remodeling, which is thought to enhance the efficacy of immunotherapy.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Humanos , Ácido Láctico , Neoplasias/terapia , Imunoterapia , Terapia de Imunossupressão , Microambiente Tumoral
5.
Semin Liver Dis ; 42(3): 271-282, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35672015

RESUMO

During biliary tree homeostasis, BECs are largely in a quiescent state and their turnover is slow for maintaining normal tissue homeostasis. BTSCs continually replenish new BECs in the luminal surface of EHBDs. In response to various types of biliary injuries, distinct cellular sources, including HPCs, BTSCs, hepatocytes, and BECs, repair or regenerate the injured bile duct. BEC, biliary epithelial cell; BTSC, biliary tree stem/progenitor cell; EHBD, extrahepatic bile ducts; HPC, hepatic progenitor cell.The biliary tree comprises intrahepatic bile ducts and extrahepatic bile ducts lined with epithelial cells known as biliary epithelial cells (BECs). BECs are a common target of various cholangiopathies for which there is an unmet therapeutic need in clinical hepatology. The repair and regeneration of biliary tissue may potentially restore the normal architecture and function of the biliary tree. Hence, the repair and regeneration process in detail, including the replication of existing BECs, expansion and differentiation of the hepatic progenitor cells and biliary tree stem/progenitor cells, and transdifferentiation of the hepatocytes, should be understood. In this paper, we review biliary tree homeostasis, repair, and regeneration and discuss the feasibility of regenerative therapy strategies for cholangiopathy treatment.


Assuntos
Sistema Biliar , Sistema Biliar/fisiologia , Células Epiteliais , Hepatócitos , Homeostase , Humanos , Regeneração
6.
Front Med (Lausanne) ; 9: 834159, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35252265

RESUMO

BACKGROUND: There is an urgent need for non-invasive methods for predicting portal hypertensive gastropathy (PHG). This study aims to develop and validate a non-invasive method based on clinical parameters for predicting PHG in patients with liver cirrhosis (LC). METHODS: The overall survival (OS) and hepatocellular carcinoma (HCC)-free survival were evaluated in LC patients, both with and without PHG. A prediction model for PHG was then constructed based on a training dataset that contained data on 492 LC patients. The discrimination, calibration, and clinical utility of the predicting nomogram were assessed using the C-index, calibration plot, and decision curve analysis. Internal validation was conducted using a bootstrapping method, and further external validation using data on the 208 other patients. RESULTS: LC patients with PHG had a worse prognosis compared with those without PHG. A nomogram was constructed using clinical parameters, such as age, hemoglobin content, platelet count and Child-Pugh class. The C-index was 0.773 (95% CI: 0.730-0.816) in the training cohort, 0.761 after bootstrapping and 0.745 (95% CI: 0.673-0.817) in the validation cohort. The AUC values were 0.767, 0.724, and 0.756 in the training, validation and total cohorts, respectively. Well-fitted calibration curves were observed in the training and validation cohorts. Decision curve analysis demonstrated that the nomogram was clinically useful at a threshold of 15%. CONCLUSION: The nomogram constructed to predict the risk of developing PHG was found to be clinically viable. Furthermore, PHG is an independent risk factor for OS of LC, but not for the occurrence of HCC.

8.
Int J Gen Med ; 14: 1589-1598, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33953606

RESUMO

BACKGROUND: Since December 2019, COVID-19 has spread throughout the world. Clinical outcomes of COVID-19 patients vary among infected individuals. Therefore, it is vital to identify patients at high risk of disease progression. METHODS: In this retrospective, multicenter cohort study, COVID-19 patients from Huoshenshan Hospital and Taikang Tongji Hospital (Wuhan, China) were included. Clinical features showing significant differences between the severe and nonsevere groups were screened out by univariate analysis. Then, these features were used to generate classifier models to predict whether a COVID-19 case would be severe or nonsevere based on machine learning. Two test sets of data from the two hospitals were gathered to evaluate the predictive performance of the models. RESULTS: A total of 455 patients were included, and 21 features showing significant differences between the severe and nonsevere groups were selected for the training and validation set. The optimal subset, with eleven features in the k-nearest neighbor model, obtained the highest area under the curve (AUC) value among the four models in the validation set. D-dimer, CRP, and age were the three most important features in the optimal-feature subsets. The highest AUC value was obtained using a support vector-machine model for a test set from Huoshenshan Hospital. Software for predicting disease progression based on machine learning was developed. CONCLUSION: The predictive models were successfully established based on machine learning, and achieved satisfactory predictive performance of disease progression with optimal-feature subsets.

9.
Gastric Cancer ; 24(2): 402-416, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33159601

RESUMO

BACKGROUND: Aberrant activation of Wnt/ß-catenin signaling by dysregulated post-translational protein modifications, especially ubiquitination is causally linked to cancer development and progression. Although Lys48-linked ubiquitination is known to regulate Wnt/ß-catenin signaling, it remains largely obscure how other types of ubiquitination, such as linear ubiquitination governs its signaling activity. METHODS: The expression and regulatory mechanism of linear ubiquitin chain assembly complex (LUBAC) on Wnt/ß-catenin signaling was examined by immunoprecipitation, western blot and immunohistochemical staining. The ubiquitination status of ß-catenin was detected by ubiquitination assay. The impacts of SHARPIN, a core component of LUBAC on malignant behaviors of gastric cancer cells were determined by various functional assays in vitro and in vivo. RESULTS: Unlike a canonical role in promoting linear ubiquitination, SHARPIN specifically interacts with ß-catenin to maintain its protein stability. Mechanistically, SHARPIN competes with the E3 ubiquitin ligase ß-Trcp1 for ß-catenin binding, thereby decreasing ß-catenin ubiquitination levels to abolish its proteasomal degradation. Importantly, SHARPIN is required for invasiveness and malignant growth of gastric cancer cells in vitro and in vivo, a function that is largely dependent on its binding partner ß-catenin. In line with these findings, elevated expression of SHARPIN in gastric cancer tissues is associated with disease malignancy and correlates with ß-catenin expression levels. CONCLUSIONS: Our findings reveal a novel molecular link connecting linear ubiquitination machinery and Wnt/ß-catenin signaling via SHARPIN-mediated stabilization of ß-catenin. Targeting the linear ubiquitination-independent function of SHARPIN could be exploited to inhibit the hyperactive ß-catenin signaling in a subset of human gastric cancers.


Assuntos
Carcinogênese/genética , Neoplasias Gástricas/genética , Ubiquitinação/genética , Ubiquitinas/genética , beta Catenina/genética , Humanos , Via de Sinalização Wnt/genética
10.
Adv Exp Med Biol ; 1207: 529-556, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671773

RESUMO

Normal gastrointestinal physiology is fundamental for all the living beings. Gastrointestinal diseases mainly include gastrointestinal motility disorders, infectious inflammation (such as Helicobacter pylori infection, cholera, and intestinal parasites), non-infectious inflammation (such as chronic gastritis and Crohn's disease), and gastrointestinal cancers. In addition, intestinal microbial disorder is also an important cause of intestinal diseases, so intestinal microecological treatment (fecal microbiota transplantation) is an important mean of treating gastrointestinal diseases. In recent years, the role of autophagy in gastrointestinal diseases has been studied extensively. Autophagy is observed under various pathological processes of the gastrointestinal tract. For example, it has been demonstrated that autophagy plays an important role in maintaining the homeostasis and integrity of intestinal epithelium. Additionally, autophagy regulates host response to H. pylori infection and development of gastrointestinal cancers. Therefore, we will discuss pivotal roles of autophagy in various gastrointestinal diseases and analyze the underlying molecular mechanisms, which may provide new therapeutic targets applicable for the treatment of gastrointestinal diseases.


Assuntos
Autofagia , Gastroenteropatias , Autofagia/efeitos dos fármacos , Cólera , Doença de Crohn , Gastrite Atrófica , Gastroenteropatias/tratamento farmacológico , Neoplasias Gastrointestinais , Infecções por Helicobacter , Humanos
11.
Gastroenterol Res Pract ; 2020: 2357840, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328093

RESUMO

AIM: To develop and validate a simple-to-use nomogram for prediction of 3-/5-year survival in patients with N0M0 hepatocellular carcinoma after curative liver resection. Patients and Methods. Patients diagnosed HCC with hepatic resection in the Surveillance, Epidemiology, and End Results (SEER) database were included to identify prognostic factors of overall survival. Multivariate Cox regression were used to create a nomogram. RESULTS: We identified 4856 HCC with hepatic resection from the SEER database. A nomogram to predict long-term survival with a C-index 0.667 (95% CI, 0.653 to 0.681) is more efficient than TNM staging with a lower C-index 0.613 (95% CI, 0.597 to 0.629). The C-index was confirmed to be 0.663 (95% CI, 0.640 to 0.686) through validation, suggesting a good discrimination and a good prediction capability. CONCLUSIONS: The nomogram is a simple and effective screening tool for assessing the prognosis of HCC with hepatic resection and assists with the planning of individual postoperative surveillance protocols.

12.
Med Sci Monit ; 26: e919896, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32090983

RESUMO

BACKGROUND Angiogenic factor with G patch and FHA domains 1 (AGGF1) is a novel identified initiator of angiogenesis through promoting the proliferation of endothelial cells. The continuous angiogenesis plays a key role in the growth, invasion, and metastasis of hepatocellular carcinoma (HCC), while the diagnostic and prognostic roles of AGGF1 for HCC need to be further studied. MATERIAL AND METHODS The mRNA sequencing datasets and clinical features of HCC patients were extracted from The Cancer Genome Atlas database. The relationship between clinical features and AGGF1 expression was analyzed by Wilcoxon test. Further validation explorations were carried out using online database Oncomine. The diagnostic receiver operating characteristic curves of AGGF1 and alpha-fetoprotein were compared to examine the diagnostic efficacy of AGGF1. Survival analysis and Gene Set Enrichment Analysis were performed to explore the prediction value and potential mechanism of AGGF1 dysregulation in HCC. RESULTS Comprehensive overexpression of AGGF1 was observed in HCC, correlating with poor overall survival. Upregulated level of AGGF1 was statistically associated with poor differentiated histological grade, advanced cancer stage and T classification. AGGF1 was a more effective diagnostic marker than alpha-fetoprotein in HCC. Several important pathways related to HCC including pathway in cancer and P53 signaling pathway were differentially enriched in the high AGGF1 expression phenotype. CONCLUSIONS AGGF1 was a potential diagnostic and prognostic marker for poor clinical outcomes in HCC patients. Moreover, vital pathways regulated by AGGF1 in HCC may include regulation of autophagy, Wnt signaling pathway, pathway in cancer, cell cycle, and P53 signaling pathway.


Assuntos
Proteínas Angiogênicas/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Biologia Computacional , Neoplasias Hepáticas/genética , Carcinoma Hepatocelular/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Fenótipo , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais
13.
Cancer Res ; 79(19): 4869-4881, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31311807

RESUMO

Cancer metastasis, a leading cause of death in patients, is associated with aberrant expression of epigenetic modifiers, yet it remains poorly defined how epigenetic readers drive metastatic growth and whether epigenetic readers are targetable to control metastasis. Here, we report that bromodomain-containing protein 4 (BRD4), a histone acetylation reader and emerging anticancer therapeutic target, promotes progression and metastasis of gastric cancer. The abundance of BRD4 in human gastric cancer tissues correlated with shortened metastasis-free gastric cancer patient survival. Consistently, BRD4 maintained invasiveness of cancer cells in vitro and their dissemination at distal organs in vivo. Surprisingly, BRD4 function in this context was independent of its putative transcriptional targets such as MYC or BCL2, but rather through stabilization of Snail at posttranslational levels. In an acetylation-dependent manner, BRD4 recognized acetylated lysine 146 (K146) and K187 on Snail to prevent Snail recognition by its E3 ubiquitin ligases FBXL14 and ß-Trcp1, thereby inhibiting Snail polyubiquitination and proteasomal degradation. Accordingly, genome-wide transcriptome analyses identified that BRD4 and Snail regulate a partially shared metastatic gene signature in gastric cancer cells. These findings reveal a noncanonical posttranscriptional regulatory function of BRD4 in maintaining cancer growth and dissemination, with immediate translational implications for treating gastric metastatic malignancies with clinically available bromodomain inhibitors. SIGNIFICANCE: These findings reveal a novel posttranscriptional regulatory function of the epigenetic reader BRD4 in cancer metastasis via stabilizing Snail, with immediate translational implication for treating metastatic malignancies with clinically available bromodomain inhibitors. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/19/4869/F1.large.jpg.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Invasividade Neoplásica/patologia , Fatores de Transcrição da Família Snail/metabolismo , Neoplasias Gástricas/patologia , Fatores de Transcrição/metabolismo , Acetilação , Animais , Progressão da Doença , Epigênese Genética/fisiologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Camundongos , Transcriptoma
14.
BMC Gastroenterol ; 19(1): 118, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31272385

RESUMO

BACKGROUND: Multiple organ failure (MOF) is a serious complication of moderately severe (MASP) and severe acute pancreatitis (SAP). This study aimed to develop and assess three machine-learning models to predict MOF. METHODS: Patients with MSAP and SAP who were admitted from July 2014 to June 2017 were included. Firstly, parameters with significant differences between patients with MOF and without MOF were screened out by univariate analysis. Then, support vector machine (SVM), logistic regression analysis (LRA) and artificial neural networks (ANN) models were constructed based on these factors, and five-fold cross-validation was used to train each model. RESULTS: A total of 263 patients were enrolled. Univariate analysis screened out sixteen parameters referring to blood volume, inflammatory, coagulation and renal function to construct machine-learning models. The predictive efficiency of the optimal combinations of features by SVM, LRA, and ANN was almost equal (AUC = 0.840, 0.832, and 0.834, respectively), as well as the Acute Physiology and Chronic Health Evaluation II score (AUC = 0.814, P > 0.05). The common important predictive factors were HCT, K-time, IL-6 and creatinine in three models. CONCLUSIONS: Three machine-learning models can be efficient prognostic tools for predicting MOF in MSAP and SAP. ANN is recommended, which only needs four common parameters.


Assuntos
Aprendizado de Máquina , Insuficiência de Múltiplos Órgãos/diagnóstico , Pancreatite/complicações , Medição de Risco/métodos , Índice de Gravidade de Doença , APACHE , Doença Aguda , Adulto , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/etiologia , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos
15.
Biochem Biophys Res Commun ; 512(2): 405-411, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-30902385

RESUMO

Human tumorigenesis resembles embryogenesis by aberrant activation of several developmental pathways including Wnt/ß-catenin signaling. Norrin is an atypical ligand for Frizzled receptor that is preferentially expressed in the endothelium to promote retinal vascularization during development. However, its expression pattern and potential roles in human cancers remain unclear. Here we report that Norrin expression is elevated in the parenchymal cells, but not endothelial cells, in gastric cancer (GC). Moreover, Norrin is required for growth and invasion of GC cells and its expression status is associated with unfavorable outcomes. However, analysis of the TGCA database demonstrates that Norrin expression status is not correlated with key target genes of Wnt/ß-catenin signaling. Among several signaling pathways hyperactivated in cancer, Norrin-depleted GC cells also display down-regulated AKT signaling except the canonical Wnt/ß-catenin signaling. Consistently, small molecule-induced cytosolic activation of AKT partially rescues the proliferative and invasive capability of Norrin-depleted cells. Together, these findings suggest a novel role of Norrin in gastric tumorigenesis that could be exploited for adjuvant therapy against the deadly malignancy.


Assuntos
Proteínas do Olho/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias Gástricas/metabolismo , Adulto , Idoso , Carcinogênese/metabolismo , Carcinogênese/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas do Olho/antagonistas & inibidores , Proteínas do Olho/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/genética , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Via de Sinalização Wnt
17.
Biomed Res Int ; 2018: 8308671, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30370307

RESUMO

AIM: We tested the hypothesis that fecal microbiota transplantation (FMT) could regulate the biotransformation of bile acids, such as deoxycholic acid (DCA) and cholic acid (CA), which in turn regulate the biosynthesis of serotonin in the gut and relieve gastrointestinal dysmotility in high-fat diet- (HFD-) induced obesity in rats. METHODS: Male Sprague-Dawley rats were randomly divided into the control diet group, HFD group, and HFD-fed with receiving FMT. HFD was fed for 12 weeks. At the end of two-week HFD, FMT was carried out for two weeks. The gastrointestinal transit, serotonin concentration, the expression of tryptophan hydroxylase 1 (TPH1) and serotonin reuptake transporter (SERT), and the levels of bile acids in intestinal contents were examined. RESULTS: Compared with the control group, the gastrointestinal transit and small intestinal serotonin concentration of HFD-fed rats were increased. In HFD-fed rats, TPH1 protein expression was increased significantly, while SERT protein expression was decreased, but not significant. The levels of CA and DCA in intestinal contents were also significantly increased in HFD-fed rats compared with the control group. After HFD-fed rats receiving FMT treatment, the gastrointestinal transit, small intestinal serotonin concentration, and TPH1 expression were decreased, while SERT expression was not affected. Moreover, the levels of CA and DCA in intestinal contents were also decreased. CONCLUSIONS: FMT could alleviate small intestinal transit in the HFD-fed rats by regulating the serotonin biosynthesis. In this process, CA and DCA may be related to the regulation of synthesis of serotonin.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Microbioma Gastrointestinal/fisiologia , Trânsito Gastrointestinal/fisiologia , Obesidade/metabolismo , Serotonina/metabolismo , Animais , Ácidos e Sais Biliares/metabolismo , Transplante de Microbiota Fecal/métodos , Masculino , Ratos , Ratos Sprague-Dawley
18.
Front Microbiol ; 9: 1921, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30197631

RESUMO

Ulcerative colitis (UC) is a chronic non-specific inflammatory disease that occurs in the colon and rectum. While fecal microbiota transplantation (FMT) is gaining attention as a clinical treatment of UC, the molecular mechanisms behind this effect have yet to be fully understood. A C57BL/6 mouse model was established to test whether FMT promotes the recovery of colon inflammation. Administration of 2% dextran sulfate sodium (DSS) for 7 days successfully induced acute colitis, as evidenced by diarrhea, hematochezia and colon shortening as well as a decrease in body weight. FMT alleviated the severity of colon mucosa injury and improved histological alterations compared with that of the DSS group. In addition, FMT promoted homeostasis of the intestinal microbiota. Furthermore, FMT upregulated the expression of aryl hydrocarbon receptor (AHR), interleukin-10 (IL-10), and transforming growth factor beta (TGF-ß) in colon tissues. These results suggest that the significant anti-inflammatory effect of FMT may be attributed to its promotion of IL-10 and TGF-ß production and AHR activation. Based on these results, FMT had a favorable therapeutic effect on DSS-induced colitis.

19.
Cancer Lett ; 430: 11-24, 2018 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-29746925

RESUMO

Tumor growth is fueled by subset of cells with stem cell properties (Cancer stem cells, CSCs). While persistent activation of Wnt/ß-catenin signaling confers CSC properties, it remains unclear how epigenetic modifications regulate Wnt target genes to dictate their self-renewal. Here, we report a novel Wnt-responsive epigenetic switch for CSC maintenance through activating the stem cell transcription factor ASCL2 in gastric carcinoma (GC). We characterize ASCL2-expressing (ASCL2+) GC cells as a subset of Wnt-responsive CSCs that depend on ASCL2 for self-renewal. High-throughput RNAi screening uncovers that the histone methyltransferase SMYD3 determines H3K4me3 status at the ASCL2 locus to promote ASCL2 expression. Moreover, SMYD3 may be transcriptionally activated by the ß-catenin/TCF4 complex, indicating that the SMYD3-ASCL2 axis may be an integral component of Wnt signaling. Consistently, SMYD3 maintains self-renewal and tumorigenicity of ASCL2+ CSCs largely through inducing ASCL2. Clinically, overexpression of SMYD3 and ASCL2 are associated with malignant progression and poor patient outcomes in GC. Together, these findings define a Wnt-responsive CSC pathway that could be exploited to identify essential regulators of the signaling output, and reveal SMYD3 as an epigenetic target for eliminating CSCs in human cancers.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma/genética , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/metabolismo , Neoplasias Gástricas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/genética , Carcinoma/mortalidade , Carcinoma/patologia , Linhagem Celular Tumoral , Autorrenovação Celular/genética , Epigênese Genética , Feminino , Técnicas de Silenciamento de Genes , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/metabolismo , RNA Interferente Pequeno/metabolismo , Estômago/patologia , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia , Análise de Sobrevida , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/genética , beta Catenina/genética , beta Catenina/metabolismo
20.
Cancer Res ; 78(16): 4680-4691, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-29776962

RESUMO

Src homology region 2 (SH2) domain-containing phosphatase 1 (SHP-1, also known as PTPN6) is a nonreceptor protein tyrosine phosphatase that acts as a negative regulator of inflammation. Emerging evidence indicates that SHP-1 plays a role in inhibiting the progression of hepatocellular carcinoma (HCC). However, the role of SHP-1 in hepatocarcinogenesis remains unknown. Here, we find that levels of SHP-1 are significantly downregulated in human HCC tissues compared with those in noncancerous tissues (P < 0.001) and inversely correlate with tumor diameters (r = -0.4130, P = 0.0002) and serum α-fetoprotein levels (P = 0.047). Reduced SHP-1 expression was associated with shorter overall survival of patients with HCC with HBV infection. Overexpression of SHP-1 suppressed proliferation, migration, invasion, and tumorigenicity of HCC cells, whereas knockdown of SHP-1 enhanced the malignant phenotype. Moreover, knockout of Ptpn6 in hepatocytes (Ptpn6HKO ) enhanced hepatocarcinogenesis induced by diethylnitrosamine (DEN) as well as metastasis of primary liver cancer in mice. Furthermore, systemic delivery of SHP-1 by an adenovirus expression vector exerted a therapeutic effect in an orthotopic model of HCC in NOD/SCID mice and DEN-induced primary liver cancers in Ptpn6HKO mice. In addition, SHP-1 inhibited the activation of JAK/STAT, NF-κB, and AKT signaling pathways, but not the MAPK pathway in primary hepatocytes from DEN-treated mice and human HCC cells. Together, our data implicate SHP-1 as a tumor suppressor of hepatocarcinogenesis and HCC progression and propose it as a novel prognostic biomarker and therapeutic target of HCC.Significance: The nonreceptor protein tyrosine phosphatase SHP-1 acts as a tumor suppressor in hepatocellular carcinoma. Cancer Res; 78(16); 4680-91. ©2018 AACR.


Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Proteínas Supressoras de Tumor/genética , Animais , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Análise em Microsséries , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
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