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1.
iScience ; 27(9): 110847, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39297166

RESUMEN

Adjuvant radiation therapy is a common treatment for breast cancer, yet its effectiveness is often limited by radioresistance in patients. Identifying novel targets to combat this radioresistance is imperative. Recent investigations show that gp78 is upregulated in drug-resistant breast cancer cells. Our study reveals that gp78 markedly increased the phosphorylation of KAP1 and promoted DNA damage repair caused by ionizing radiation. Mechanistically, gp78 degrades phosphatases (PPP1CC/PPP2CA) in a ubiquitination-dependent manner. PPP1CC and PPP2CA are crucial regulators of KAP1 phosphorylation in response to DNA damage. Therefore, gp78 leads to a notable elevation in the phosphorylation of KAP1 by degrading phosphatases, thereby promoting the DNA damage repair process and increasing the radioresistance of tumor cells. The identification of gp78 as a pivotal regulator in radioresistance suggests a promising avenue for intervention. Combining blockade strategies targeting gp78 holds a signification potential for reversing radioresistance and improving the efficacy of breast cancer radiotherapy.

2.
Cell Death Differ ; 31(8): 1085-1098, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38783090

RESUMEN

The pseudokinase mixed lineage kinase domain-like (MLKL) is an essential component of the activation of the necroptotic pathway. Emerging evidence suggests that MLKL plays a key role in liver disease. However, how MLKL contributes to hepatocarcinogenesis has not been fully elucidated. Herein, we report that MLKL is upregulated in a diethylnitrosamine (DEN)-induced murine HCC model and is associated with human hepatocellular carcinomas. Hepatocyte-specific MLKL knockout suppresses the progression of hepatocarcinogenesis. Conversely, MLKL overexpression aggravates the initiation and progression of DEN-induced HCC. Mechanistic study reveals that deletion of MLKL significantly increases the activation of autophagy, thereby protecting against hepatocarcinogenesis. MLKL directly interacts with AMPKα1 and inhibits its activity independent of its necroptotic function. Mechanistically, MLKL serves as a bridging molecule between AMPKα1 and protein phosphatase 1B (PPM1B), thus enhancing the dephosphorylation of AMPKα1. Consistently, MLKL expression correlates negatively with AMPKα1 phosphorylation in HCC patients. Taken together, our findings highlight MLKL as a novel AMPK gatekeeper that plays key roles in inhibiting autophagy and driving hepatocarcinogenesis, suggesting that the MLKL-AMPKα1 axis is a potential therapeutic target for HCC.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Autofagia , Carcinoma Hepatocelular , Neoplasias Hepáticas , Proteínas Quinasas , Animales , Humanos , Masculino , Ratones , Proteínas Quinasas Activadas por AMP/metabolismo , Carcinogénesis/metabolismo , Carcinogénesis/patología , Carcinogénesis/genética , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/inducido químicamente , Dietilnitrosamina/toxicidad , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Ratones Endogámicos C57BL , Ratones Noqueados , Fosforilación , Proteínas Quinasas/metabolismo
3.
Int J Biol Sci ; 18(8): 3447-3457, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35637973

RESUMEN

Protein palmitoylation is an increasingly investigated form of post-translational lipid modification that affects protein localization, accumulation, secretion and function. Recently, emerging findings have revealed that protein palmitoylation is crucial for many tumor-related signaling pathways, such as EGFR, RAS, PD-1/PD-L1 signaling, affecting the occurrence, progression and therapeutic response of tumors. Protein palmitoylation and its modifying enzymes, including palmitoylases and depalmitoylases, are expected to be new targets for effective tumor treatment. Recognizing the significance of palmitoylation modification on protein stability, localization and downstream signal regulation, this review focuses on the regulatory roles of protein palmitoylation and its modifying enzymes in tumor cell signal transduction, aiming to bring new ideas for effective cancer prevention and treatment.


Asunto(s)
Lipoilación , Neoplasias , Neoplasias/terapia , Procesamiento Proteico-Postraduccional , Transporte de Proteínas , Transducción de Señal
4.
J Cell Mol Med ; 25(19): 9411-9426, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34453479

RESUMEN

KCTD11 has been reported to be a potential tumour suppressor in several tumour types. However, the expression of KCTD11 and its role has not been reported in human non-small cell lung cancer (NSCLC). Whether its potential molecular mechanism is related to its BTB domain is also unknown. The expression of KCTD11 in 139 NSCLC tissue samples was detected by immunohistochemistry, and its correlation with clinicopathological factors was analysed. The effect of KCTD11 on the biological behaviour of lung cancer cells was verified in vitro and in vivo. Its effect on the epithelial-mesenchymal transition(EMT)process and the Wnt/ß-catenin and Hippo/YAP pathways were observed by Western blot, dual-luciferase assay, RT-qPCR, immunofluorescence and immunoprecipitation. KCTD11 is under-expressed in lung cancer tissues and cells and was negatively correlated with the degree of differentiation, tumour-node-metastasis (TNM) stage and lymph node metastasis. Low KCTD11 expression was associated with poor prognosis. KCTD11 overexpression inhibited the proliferation and migration of lung cancer cells. Further studies indicated that KCTD11 inhibited the Wnt pathway, activated the Hippo pathway and inhibited EMT processes by inhibiting the nuclear translocation of ß-catenin and YAP. KCTD11 lost its stimulatory effect on the Hippo pathway after knock down of ß-catenin. These findings confirm that KCTD11 inhibits ß-catenin and YAP nuclear translocation as well as the malignant phenotype of lung cancer cells by interacting with ß-catenin. This provides an important experimental basis for the interaction between KCTD11, ß-catenin and YAP, further revealing the link between the Wnt and Hippo pathways.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Vía de Señalización Hippo , Neoplasias Pulmonares/metabolismo , Transferasas/metabolismo , Vía de Señalización Wnt , beta Catenina/metabolismo , Adulto , Anciano , Animales , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Modelos Animales de Enfermedad , Transición Epitelial-Mesenquimal/genética , Femenino , Expresión Génica , Xenoinjertos , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/patología , Masculino , Ratones , Persona de Mediana Edad , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Fosforilación , Pronóstico , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Transporte de Proteínas , Factores de Transcripción/metabolismo , Transferasas/química , Transferasas/genética
5.
Cancer Sci ; 112(10): 4064-4074, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34251713

RESUMEN

Programmed cell death ligand 1 (PD-L1) is a major immunosuppressive checkpoint protein expressed by tumor cells to subvert anticancer immunity. Recent studies have shown that ionizing radiation (IR) upregulates the expression of PD-L1 in tumor cells. However, whether an IR-induced DNA damage response (DDR) directly regulates PD-L1 expression and the functional significance of its upregulation are not fully understood. Here, we show that IR-induced upregulation of PD-L1 expression proceeds through both transcriptional and post-translational mechanisms. Upregulated PD-L1 was predominantly present on the cell membrane, resulting in T-cell apoptosis in a co-culture system. Using mass spectrometry, we identified PD-L1 interacting proteins and found that BCLAF1 (Bcl2 associated transcription factor 1) is an important regulator of PD-L1 in response to IR. BCLAF1 depletion decreased PD-L1 expression by promoting the ubiquitination of PD-L1. In addition, we show that CMTM6 is upregulated in response to IR and participates in BCLAF1-dependent PD-L1 upregulation. Finally, we demonstrated that the ATM/BCLAF1/PD-L1 axis regulated PD-L1 stabilization in response to IR. Together, our findings reveal a novel regulatory mechanism of PD-L1 expression in the DDR.


Asunto(s)
Antígeno B7-H1/metabolismo , Radiación Ionizante , Proteínas Represoras/fisiología , Proteínas Supresoras de Tumor/fisiología , Apoptosis , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Antígeno B7-H1/efectos de la radiación , Línea Celular Tumoral , Membrana Celular/metabolismo , Técnicas de Cocultivo , Daño del ADN , Humanos , Células Jurkat , Proteínas con Dominio MARVEL/metabolismo , Proteínas con Dominio MARVEL/efectos de la radiación , Espectrometría de Masas , Proteínas de la Mielina/metabolismo , Proteínas de la Mielina/efectos de la radiación , Proteínas de Neoplasias/metabolismo , Modificación Traduccional de las Proteínas , Procesamiento Proteico-Postraduccional , Proteínas Represoras/deficiencia , Linfocitos T/citología , Linfocitos T/efectos de la radiación , Proteínas Supresoras de Tumor/deficiencia , Ubiquitinación , Regulación hacia Arriba/efectos de la radiación
6.
Onco Targets Ther ; 14: 2227-2233, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33824593

RESUMEN

In adults, yolk sac tumors (YSTs) in the nasal cavity and paranasal sinuses are very rare. To date, only six cases have been reported in the English literature. YSTs in adults are often accompanied by cancer, teratocarcinosarcoma, and other malignant components. Here, we have reported a case of nasal tumor in a 55-year-old man with nasal obstruction and epistaxis. Morphologically, the tumor showed histological characteristics of pure YST. Immunohistochemical staining showed diffuse expression of SALL4, CDX2, and GPC-3 accompanied by sporadic expression of alpha-fetoprotein (AFP) and CD117. After 20 and 40 days of operation, the serum AFP level was 220.30 and 43.60 ng/mL (normal, <7 ng/mL), respectively, which supported the pathological diagnosis of YST. However, we further performed immunohistochemical staining and fluorescence in situ hybridization using an INI-1 probe to detect the status of INI-1 in tumor cells. The results revealed that INI-1 was absent in tumor cells. Hence, we corrected the diagnosis to SMARCB1 (INI-1)-deficient carcinoma of the nasal cavity with YST differentiation. The patient underwent surgery and adjuvant radiotherapy in our hospital without evidence of recurrence or metastasis at the 6-month follow-up. The serum AFP level had also normalized. In conclusion, our case demonstrates that INI-1-deficient carcinoma may exhibit, a pure YST differentiation and immunophenotype, and elevated serum AFP levels. In adults, YST in the nasal cavity may represent INI-1-deficient carcinoma, which may be a potential diagnostic pitfall.

7.
Front Oncol ; 10: 565414, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33364189

RESUMEN

ZDHHC-protein acyltransferases (ZDHHCs) are a family of 23 signature Asp-His-His-Cys (DHHC) domain-containing enzymes that mediate palmitoylation by covalent attachment of the 16-carbon fatty acid palmitate to thiol groups of specific cysteine residues in substrate proteins. Emerging evidence has shown abnormal expression of ZDHHCs in a variety of disease states, including cancer. Kidney renal clear cell carcinoma (KIRC) is the eighth most common type of cancer, which accounts for the majority of malignant kidney tumors. However, there are currently no effective therapeutic targets or biomarkers for clinical treatment and prognosis in KIRC. In this study, we first analyzed the expression pattern of the 23 ZDHHCs in KIRC using TCGA and GEPIA database, and found that the expression of ZDHHC2, 3, 6, 14, 15, 21, and 23 was significantly down-regulated whereas the expression of ZDHHC9, 17, 18, 19 and 20 was significantly up-regulated in KIRC patient tissues vs. normal tissues. And the expression of ZDHHC2, 3, 6, 9, 14, 15, and 21 in tumors decreased with the increase of the pathological stage of KIRC patients. Notably, KIRC patients with decreased expression of ZDHHC3, 6, 9, 14, 15, 17, 20, 21, 23 and increased expression of ZDHHC19 were significantly associated with poor prognosis. Further, we found that there was a significant correlation between ZDHHC3, 6, 9, 14, 15, 17, 19, 20, 21, 23 expressions and immune cell infiltration. Besides, high mRNA expression was the most common type of gene alteration and there was a high correlation among the expression of ZDHHC6, 17, 20 and 21. Finally, function prediction indicated that the immune or metabolic disorders or the activation of oncogenic signaling pathways caused by abnormal expression of these ZDHHCs may be important mechanisms of tumor progression and poor prognosis in patients with KIRC. Our results may provide novel insight for identifying tumor markers or molecular targets for the treatment of KIRC.

8.
Cancer Biol Med ; 17(3): 640-651, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32944396

RESUMEN

Objective: Mitotic arrest-deficient protein 1 (MAD1) is a kinetochore protein essential for the mitotic spindle checkpoint. Proteomic studies have indicated that MAD1 is a component of the DNA damage response (DDR) pathway. However, whether and how MAD1 might be directly involved in the DDR is largely unknown. Methods: We ectopically expressed the wild type, or a phosphorylation-site--mutated form of MAD1 in MAD1 knockdown cells to look for complementation effects. We used the comet assay, colony formation assay, immunofluorescence staining, and flow cytometry to assess the DDR, radiosensitivity, and the G2/M checkpoint. We employed co-immunoprecipitation followed by mass spectrometry to identify MAD1 interacting proteins. Data were analyzed using the unpaired Student's t-test. Results: We showed that MAD1 was required for an optimal DDR, as knocking down MAD1 resulted in impaired DNA repair and hypersensitivity to ionizing radiation (IR). We found that IR-induced serine 214 phosphorylation was ataxia-telangiectasia mutated (ATM) kinase-dependent. Mutation of serine 214 to alanine failed to rescue the phenotypes of MAD1 knockdown cells in response to IR. Using mass spectrometry, we identified a protein complex mediated by MAD1 serine 214 phosphorylation in response to IR. Among them, we showed that KU80 was a key protein that displayed enhanced interaction with MAD1 after DNA damage. Finally, we showed that MAD1 interaction with KU80 required serine 214 phosphorylation, and it was essential for activation of DNA protein kinases catalytic subunit (DNA-PKcs). Conclusions: MAD1 serine 214 phosphorylation mediated by ATM kinase in response to IR was required for the interaction with KU80 and activation of DNA-PKCs.


Asunto(s)
Proteínas de la Ataxia Telangiectasia Mutada/deficiencia , Proteínas de Ciclo Celular/metabolismo , Daño del ADN/genética , Proteína Quinasa Activada por ADN/metabolismo , Autoantígeno Ku/metabolismo , Animales , Proteínas de la Ataxia Telangiectasia Mutada/antagonistas & inhibidores , Proteínas de Ciclo Celular/genética , Daño del ADN/efectos de la radiación , Proteína Quinasa Activada por ADN/genética , Femenino , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Células HCT116 , Células HeLa , Humanos , Autoantígeno Ku/genética , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Mutación , Fosforilación , Tolerancia a Radiación/genética , Radiación Ionizante , Ensayos Antitumor por Modelo de Xenoinjerto
9.
EBioMedicine ; 57: 102849, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32580141

RESUMEN

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is associated with altered production of secreted proteins. Increased understanding of secreted proteins could lead to improved prediction and treatment of NAFLD. Here, we aimed to discover novel secreted proteins in humans that are associated with hepatic fat content using unbiased proteomic profiling strategy, and how the identified Thbs1 modulates lipid metabolism and hepatic steatosis. METHOD: NAFLD patients were enrolled and treated with lifestyle intervention. Patients who underwent liver biopsy were enrolled for analyzing the correlation between circulating Thbs1 and liver steatosis. Mice were fed on high-fat, high-sucrose diet and treated with recombinant Thbs1. Primary hepatocytes isolated from CD36 knockout (CD36-/-) mice and their wild-type littermates (controls) were treated with glucose plus insulin for 24 h together with or without recombinant Thbs1. FINDING: Serum Thbs1 levels are increased in participants with NAFLD and positively associated with liver steatosis grades. Improvement of liver steatosis after lifestyle intervention was accompanied with significant reduction of serum Thbs1 levels. Pharmacological administration of recombinant human Thbs1 attenuates hepatic steatosis in diet-induced obese mice. Treatment with Thbs1 protein or stably overexpression of Thbs1 causes a significant reduction of lipid accumulation in primary hepatocytes or HepG2 cells exposed to high glucose plus insulin, suggesting that Thbs1 regulates lipid metabolism in a hepatocyte-autonomous manner. Mechanistically, Thbs1 inhibits cleavage and processing of SREBP-1, leading to a reduction of target lipogenic gene expression and hepatic steatosis. Inhibitory effects of Thbs1 on lipogenesis and triglyceride accumulation are abrogated in CD36 deficient primary hepatocytes exposed to high glucose plus insulin. Interestingly, beneficial effects of Thbs1 on lipid accumulation are observed in primary hepatocytes treated with a Thbs1 nonapeptide mimetic ABT-526. INTERPRETATION: Thbs1 is a biomarker for NAFLD in humans, and pharmacological and genetic approaches for the modulation of Thbs1 activity may have the therapeutic potential for treating hepatic steatosis. FUND: A full list of funding bodies that contributed to this study can be found in the Funding Sources section.


Asunto(s)
Hígado Graso/genética , Metabolismo de los Lípidos/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Proteómica , Trombospondina 1/genética , Animales , Antígenos CD36/genética , Dieta Alta en Grasa/efectos adversos , Hígado Graso/dietoterapia , Hígado Graso/metabolismo , Hígado Graso/patología , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Insulina/genética , Insulina/metabolismo , Resistencia a la Insulina/genética , Lipogénesis/genética , Hígado/metabolismo , Hígado/patología , Ratones , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico/dietoterapia , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Fragmentos de Péptidos/farmacología , Trombospondina 1/farmacología , Triglicéridos/sangre
10.
Hepatology ; 71(4): 1421-1436, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31469186

RESUMEN

BACKGROUND AND AIMS: STAT3, a member of the signal transducer and activator of transcription (STAT) family, is strongly associated with liver injury, inflammation, regeneration, and hepatocellular carcinoma development. However, the signals that regulate STAT3 activity are not completely understood. APPROACH AND RESULTS: Here we characterize CREB/ATF bZIP transcription factor CREBZF as a critical regulator of STAT3 in the hepatocyte to repress liver regeneration. We show that CREBZF deficiency stimulates the expression of the cyclin gene family and enhances liver regeneration after partial hepatectomy. Flow cytometry analysis reveals that CREBZF regulates cell cycle progression during liver regeneration in a hepatocyte-autonomous manner. Similar results were observed in another model of liver regeneration induced by intraperitoneal injection of carbon tetrachloride (CCl4 ). Mechanistically, CREBZF potently associates with the linker domain of STAT3 and represses its dimerization and transcriptional activity in vivo and in vitro. Importantly, hepatectomy-induced hyperactivation of cyclin D1 and liver regeneration in CREBZF liver-specific knockout mice was reversed by selective STAT3 inhibitor cucurbitacin I. In contrast, adeno-associated virus-mediated overexpression of CREBZF in the liver inhibits the expression of the cyclin gene family and attenuates liver regeneration in CCl4 -treated mice. CONCLUSIONS: These results characterize CREBZF as a coregulator of STAT3 to inhibit regenerative capacity, which may represent an essential cellular signal to maintain liver mass homeostasis. Therapeutic approaches to inhibit CREBZF may benefit the compromised liver during liver transplantation.


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Regulación de la Expresión Génica , Regeneración Hepática/genética , Hígado/fisiología , Factor de Transcripción STAT3/genética , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Tetracloruro de Carbono/toxicidad , Ciclo Celular/genética , Eliminación de Gen , Hepatocitos/efectos de los fármacos , Hepatocitos/fisiología , Hígado/efectos de los fármacos , Hígado/lesiones , Redes y Vías Metabólicas , Ratones , Ratones Noqueados
11.
Exp Mol Med ; 51(9): 1-14, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31506421

RESUMEN

Microbial metabolites have emerged as critical components that mediate the metabolic effects of the gut microbiota. Here, we show that indole-3-propionic acid (IPA), a tryptophan metabolite produced by gut bacteria, is a potent anti-non-alcoholic steatohepatitis (NASH) microbial metabolite. Here, we demonstrate that administration of IPA modulates the microbiota composition in the gut and inhibits microbial dysbiosis in rats fed a high-fat diet. IPA induces the expression of tight junction proteins, such as ZO-1 and Occludin, and maintains intestinal epithelium homeostasis, leading to a reduction in plasma endotoxin levels. Interestingly, IPA inhibits NF-κB signaling and reduces the levels of proinflammatory cytokines, such as TNFα, IL-1ß, and IL-6, in response to endotoxin in macrophages to repress hepatic inflammation and liver injury. Moreover, IPA is sufficient to inhibit the expression of fibrogenic and collagen genes and attenuate diet-induced NASH phenotypes. The beneficial effects of IPA on the liver are likely mediated through inhibiting the production of endotoxin in the gut. These findings suggest a protective role of IPA in the control of metabolism and uncover the gut microbiome and liver cross-talk in regulating the intestinal microenvironment and liver pathology via a novel dietary nutrient metabolite. IPA may provide a new therapeutic strategy for treating NASH.


Asunto(s)
Microbioma Gastrointestinal/efectos de los fármacos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Ocludina/genética , Propionatos/farmacología , Proteína de la Zonula Occludens-1/genética , Animales , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Disbiosis/tratamiento farmacológico , Disbiosis/genética , Disbiosis/metabolismo , Disbiosis/microbiología , Endotoxinas/metabolismo , Microbioma Gastrointestinal/genética , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Indoles/farmacología , Interleucina-1beta , Interleucina-6/genética , Hígado/efectos de los fármacos , Hígado/lesiones , Hígado/patología , Macrófagos/efectos de los fármacos , FN-kappa B/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/microbiología , Ratas , Triptófano/metabolismo , Factor de Necrosis Tumoral alfa/genética
12.
Cancer Lett ; 459: 100-111, 2019 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-31158430

RESUMEN

The mixed lineage kinase domain-like protein (MLKL) has emerged as a critical mediator of necroptosis, which results in the release of cellular damage-associated molecular patterns (DAMPs). However, its physiological role in regulating inflammation is not fully understood. We herein showed that Mlkl-/- mice were highly susceptible to colitis and colitis-associated tumorigenesis (CAT), which was associated with massive leukocyte infiltration and increased inflammatory responses. Moreover, we used bone marrow transplantation to reveal that MLKL in inflammatory cells is crucial for its role on colitis. Intestinal mucosal tissue and polyps isolated from Mlkl-/- mice exhibited increased ERK activation and elevated expression of genes associated with inflammation and cancer. Mechanistically, enhanced inflammation in Mlkl-/- mice was due to MEK/ERK activation particularly in dendritic cells (DCs). Our results demonstrate the role of MLKL in maintaining intestinal homeostasis and protecting against colitis and tumorigenesis.


Asunto(s)
Colitis/enzimología , Neoplasias del Colon/inmunología , Proteínas Quinasas/inmunología , Animales , Células de la Médula Ósea/enzimología , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/patología , Carcinogénesis/genética , Carcinogénesis/metabolismo , Carcinogénesis/patología , Colitis/genética , Colitis/inmunología , Colitis/patología , Neoplasias del Colon/enzimología , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Citocinas/biosíntesis , Células Dendríticas/enzimología , Células Dendríticas/inmunología , Células Dendríticas/patología , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Mucosa Intestinal/enzimología , Mucosa Intestinal/inmunología , Mucosa Intestinal/patología , Macrófagos/enzimología , Macrófagos/inmunología , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Quinasas/deficiencia , Proteínas Quinasas/genética
13.
Int J Clin Exp Pathol ; 12(4): 1118-1123, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31933927

RESUMEN

Pleomorphic xanthoastrocytoma (PXA) is a relatively rare, low grade astrocytic tumor that usually affects children as well as young adults. The reported cases were predominantly located superficially in the temporal lobe. To our knowledge, so far only two cases of PXA occurring in lateral ventricle were reported in English literature. Herein, we present the third case of PXA intra-lateral ventricle in a 28-year-old Chinese male. Histologically, the tumor was relatively well circumscribed and consisted of spindle-shaped, ovoid, and multinuclear giant cells admixed with scattered eosinophilic granular bodies, inflammatory cells, and xanthomatous cells. Immunohistochemically, the tumor cells were strongly positive for S-100, GFAP, oligo-2 and vimentin, focally positive for synaptophysin and CD34, and negative for cytokeratin, EMA, NeuN and IDH1. Ki-67 proliferation index was approximately 2%. A BRAF V600E mutation was then identified in the tumor. Based on morphologic features, the immunohistochemical staining and BRAF V600E mutation, the tumor was diagnosed as a PXA. Because of the presence of the bizarre multinuclear giant cells and xanthomatous cells and the unusual location, PXA was easily misdiagnosed as a high-grade tumor. It should be noted that PXA was also an important differential diagnosis for intraventricular tumors.

14.
Hepatology ; 68(4): 1361-1375, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29637572

RESUMEN

Insulin is critical for the regulation of de novo fatty acid synthesis, which converts glucose to lipid in the liver. However, how insulin signals are transduced into the cell and then regulate lipogenesis remains to be fully understood. Here, we identified CREB/ATF bZIP transcription factor (CREBZF) of the activating transcription factor/cAMP response element-binding protein (ATF/CREB) gene family as a key regulator for lipogenesis through insulin-Akt signaling. Insulin-induced gene 2a (Insig-2a) decreases during refeeding, allowing sterol regulatory element binding protein 1c to be processed to promote lipogenesis; but the mechanism of reduction is unknown. We show that Insig-2a inhibition is mediated by insulin-induced CREBZF. CREBZF directly inhibits transcription of Insig-2a through association with activating transcription factor 4. Liver-specific knockout of CREBZF causes an induction of Insig-2a and Insig-1 and resulted in repressed lipogenic program in the liver of mice during refeeding or upon treatment with streptozotocin and insulin. Moreover, hepatic CREBZF deficiency attenuates hepatic steatosis in high-fat, high-sucrose diet-fed mice. Importantly, expression levels of CREBZF are increased in livers of diet-induced insulin resistance or genetically obese ob/ob mice and humans with hepatic steatosis, which may underscore the potential role of CREBZF in the development of sustained lipogenesis in the liver under selective insulin resistance conditions. CONCLUSION: These findings uncover an unexpected mechanism that couples changes in extracellular hormonal signals to hepatic lipid homeostasis; disrupting CREBZF function may have the therapeutic potential for treating fatty liver disease and insulin resistance. (Hepatology 2018).


Asunto(s)
Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Hígado Graso/patología , Regulación de la Expresión Génica , Resistencia a la Insulina/genética , Lipogénesis/genética , Análisis de Varianza , Animales , Biopsia con Aguja , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Hígado Graso/genética , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Inmunohistoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Distribución Aleatoria , Transducción de Señal
15.
Sci Rep ; 7(1): 11340, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28900305

RESUMEN

Oxidative stress is thought to be critical for the pathogenesis of hepatic steatosis and its progress to non-alcoholic steatohepatitis. Berberine (BBR) can improve hepatic steatosis. In this study, we investigated the role of BBR in ameliorating oxidative stress. Lipid accumulation was measured in the livers of C57BL/6 mice fed a high fat diet (HFD) or a normal diet for 8 weeks, then either received BBR or vehicle for the study duration. Nrf2 distribution was detected in male Sprague-Dawley rats' livers in vivo and in Huh7 cells in vitro. ROS generation and mitochondrial complex expression was measured in Huh7 cells. HepG2 cells were employed for the measurement of oxygen consumption rates. Our results showed that BBR reduced triglyceride accumulation in the liver of HFD-fed mice. The activation and nuclear distribution of Nrf2 was decreased in the hepatocytes of rats that received BBR treatment, while on a HFD. BBR also markedly reduced Nox2-dependent cytoplasmic ROS production and mitochondrial ROS production, which was mediated by the down-regulation of Complex I and III expression. In conclusion, BBR has a great potential to reduce the effects of oxidative stress, which likely contributes to its protective effect in inhibiting the progression of hepatic steatosis to steatohepatitis.


Asunto(s)
Berberina/farmacología , Carcinoma Hepatocelular/metabolismo , Ácidos Grasos/metabolismo , Neoplasias Hepáticas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Línea Celular Tumoral , Dieta Alta en Grasa/efectos adversos , Hepatocitos/efectos de los fármacos , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , NADPH Oxidasa 2/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Especies Reactivas de Oxígeno/metabolismo
16.
Diabetes ; 65(7): 1904-15, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27207533

RESUMEN

The endoplasmic reticulum quality control protein activating transcription factor 6 (ATF6) has emerged as a novel metabolic regulator. Here, we show that adenovirus-mediated overexpression of the dominant-negative form of ATF6 (dnATF6) increases susceptibility to develop hepatic steatosis in diet-induced insulin-resistant mice and fasted mice. Overexpression of dnATF6 or small interfering RNA-mediated knockdown of ATF6 decreases the transcriptional activity of peroxisome proliferator-activated receptor α (PPARα)/retinoid X receptor complex, and inhibits oxygen consumption rates in hepatocytes, possibly through inhibition of the binding of PPARα to the promoter of its target gene. Intriguingly, ATF6 physically interacts with PPARα, enhances the transcriptional activity of PPARα, and triggers activation of PPARα downstream targets, such as CPT1α and MCAD, in hepatocytes. Furthermore, hepatic overexpression of the active form of ATF6 promotes hepatic fatty acid oxidation and protects against hepatic steatosis in diet-induced insulin-resistant mice. These data delineate the mechanism by which ATF6 controls the activity of PPARα and hepatic mitochondria fatty acid oxidation. Therefore, strategies to activate ATF6 could be used as an alternative avenue to improve liver function and treat hepatic steatosis in obesity.


Asunto(s)
Factor de Transcripción Activador 6/metabolismo , Ácidos Grasos/metabolismo , Hígado Graso/metabolismo , Células Secretoras de Insulina/fisiología , Metabolismo de los Lípidos/fisiología , Hígado/metabolismo , PPAR alfa/metabolismo , Factor de Transcripción Activador 6/genética , Animales , Composición Corporal/fisiología , Dieta , Ayuno/metabolismo , Hepatocitos/metabolismo , Masculino , Ratones , Mitocondrias/metabolismo , Obesidad/metabolismo , Consumo de Oxígeno/fisiología , Interferencia de ARN
17.
Theriogenology ; 84(6): 839-45, 2015 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-26208435

RESUMEN

Ovarian follicular cysts are anovulatory follicular structures that have been identified in sows and are known to cause infertility. The pathogenesis of follicular cysts remains poorly understood. Hormones play key roles in the formation and persistence of cysts. The hormone inhibin is a member of the TGF-ß superfamily and is named for its negative regulation of FSH, another hormone that controls follicular recruitment and growth. In the present study, 48 sows with follicular cysts and 60 normal sows with no cysts were screened for mutations in the inhibin-α gene to examine the association of inhibin-α gene polymorphisms with the presence of follicular cysts. The results show that the c.-42G>A and c.3222G>A polymorphisms are significantly associated with follicular cysts and that sows with c.-42GG and c.3222GG genotypes have lower risk of developing cysts. Our findings may provide novel biological biomarkers and promising gene therapy candidates for follicular cyst formation in sows, which would greatly benefit pig breeding programs.


Asunto(s)
Quiste Folicular/genética , Inhibinas/genética , Folículo Ovárico/patología , Polimorfismo Genético , Porcinos/genética , Animales , Análisis Mutacional de ADN , Femenino , Líquido Folicular/metabolismo , Estudios de Asociación Genética , Genotipo , Inhibinas/metabolismo , Polimorfismo de Longitud del Fragmento de Restricción
18.
Zhonghua Wei Chang Wai Ke Za Zhi ; 16(3): 264-7, 2013 Mar.
Artículo en Chino | MEDLINE | ID: mdl-23536349

RESUMEN

OBJECTIVE: To investigate the short-term efficacy of complete mesocolic excision (CME). METHODS: Clinical data of 62 cases of colon cancer (I-III phase) with radical resection including CME surgery group of 31 cases and traditional surgery group of 31 cases from January 2011 to October 2011 in Peking University People's Hospital were retrospective analyzed. RESULTS: The number of removed lymph node in CME and traditional resection group was 22.5±1.8 and 17.6±1.3 respectively (P<0.05) and the positive rate of lymph node in mesentery root was 9.7% (3/31) in CME surgery group. Operative blood loss was (123.5±17.6) ml and (143.5±15.3) ml in CME and traditional resection group without significant difference (P>0.05). Except for more abdominal drainage volume of 3 days post-operation in CME group (P<0.05), the postoperative recovery indicators of postoperative drainage tube removed time, exhaust time, eating time, and the socioeconomic effects indicators of postoperative hospitalization, hospitalization costs were not significantly different between two groups (all P>0.05). Postoperative intestinal obstruction occurred in 3 cases and 4 cases, lymph fistula in 2 cases and 0 case, wound dehiscence in 1 case and 1 case in CME group and traditional resection group respectively. Postoperative complication rate was not significantly different (19.4% vs. 16.1%, P>0.05). CONCLUSION: Compared with traditional radical surgery, CME sweeps lymph nodes more thoroughly, including lymph nodes of mesocolic roots, and does not affect postoperative recovery and increase the risk of postoperative complications.


Asunto(s)
Neoplasias del Colon/cirugía , Mesocolon/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
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