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1.
Adv Sci (Weinh) ; 11(28): e2401845, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38757623

RESUMO

The limited success of current targeted therapies for pancreatic cancer underscores an urgent demand for novel treatment modalities. The challenge in mitigating this malignancy can be attributed to the digestive organ expansion factor (DEF), a pivotal yet underexplored factor in pancreatic tumorigenesis. The study uses a blend of in vitro and in vivo approaches, complemented by the theoretical analyses, to propose DEF as a promising anti-tumor target. Analysis of clinical samples reveals that high expression of DEF is correlated with diminished survival in pancreatic cancer patients. Crucially, the depletion of DEF significantly impedes tumor growth. The study further discovers that DEF binds to p65, shielding it from degradation mediated by the ubiquitin-proteasome pathway in cancer cells. Based on these findings and computational approaches, the study formulates a DEF-mimicking peptide, peptide-031, designed to disrupt the DEF-p65 interaction. The effectiveness of peptide-031 in inhibiting tumor proliferation has been demonstrated both in vitro and in vivo. This study unveils the oncogenic role of DEF while highlighting its prognostic value and therapeutic potential in pancreatic cancer. In addition, peptide-031 is a promising therapeutic agent with potent anti-tumor effects.


Assuntos
Proliferação de Células , Neoplasias Pancreáticas , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Humanos , Camundongos , Animais , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Camundongos Nus , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/genética
2.
Adv Sci (Weinh) ; 10(17): e2205345, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37068188

RESUMO

The role of zinc in hematopoiesis is currently unclear. Here, SLC39A10 (ZIP10) is identified as a key zinc transporter in hematopoiesis. The results show that in zebrafish, Slc39a10 is a key regulator of the response to zinc deficiency. Surprisingly, both slc39a10 mutant zebrafish and hematopoietic Slc39a10-deficient mice develop a more severe form of impaired hematopoiesis than animals lacking transferrin receptor 1, a well-characterized iron gatekeeper, indicating that zinc plays a larger role than iron in hematopoiesis, at least in early hematopoietic stem cells (HSCs). Furthermore, it is shown that loss of Slc39a10 causes zinc deficiency in fetal HSCs, which in turn leads to DNA damage, apoptosis, and G1 cell cycle arrest. Notably, zinc supplementation largely restores colony formation in HSCs derived from hematopoietic Slc39a10-deficient mice. In addition, inhibiting necroptosis partially restores hematopoiesis in mouse HSCs, providing mechanistic insights into the requirement for zinc in mediating hematopoiesis. Together, these findings indicate that SLC39A10 safeguards hematopoiesis by protecting against zinc deficiency-induced necroptosis, thus providing compelling evidence that SLC39A10 and zinc homeostasis promote the development of fetal HSCs. Moreover, these results suggest that SLC39A10 may serve as a novel therapeutic target for treating anemia and zinc deficiency-related disorders.


Assuntos
Hematopoese , Peixe-Zebra , Camundongos , Animais , Peixe-Zebra/metabolismo , Zinco/metabolismo , Ferro
3.
Front Immunol ; 11: 585034, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33193404

RESUMO

Glioblastoma (GBM) is one of the most prevalent malignant brain tumors with poor prognosis. Increasing evidence has revealed that infiltrating immune cells and other stromal components in the tumor microenvironment (TME) are associated with prognosis of GBM. The aim of the present study was to identify immune cells and immune-related genes extracted from TME in GBM. RNA-sequencing and clinical data of GBM were downloaded from The Cancer Genome Atlas (TCGA). Four survival-related immune cells were identified via Kaplan-Meier survival analysis and immune-related differentially expressed genes (DEGs) screened. Functional enrichment and protein-protein interaction (PPI) networks for the genes were constructed. In addition, we identified 24 hub genes and the expressions of 6 of the genes were significantly associated with prognosis of GBM. Finally, the genes were validated in single-cell sequencing studies of GBM, and the immune cells validated in an independent GBM cohort from the Chinese Glioma Genome Atlas (CGGA). Overall, 24 immune-related genes infiltrating the tumor microenvironment were identified in the present study, which could serve as novel biomarkers and immune therapeutic targets.


Assuntos
Neoplasias Encefálicas/imunologia , Glioblastoma/imunologia , Microambiente Tumoral/imunologia , Perfilação da Expressão Gênica , Humanos , Evasão Tumoral/imunologia
4.
Haematologica ; 105(8): 2071-2082, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31601687

RESUMO

Transferrin receptor 1 (Tfr1) mediates the endocytosis of diferric transferrin in order to transport iron, and Tfr1 has been suggested to play an important role in hematopoiesis. To study the role of Tfr1 in hematopoiesis, we generated hematopoietic stem cell (HSC) specific Tfr1 knockout mice. We found that Tfr1 conditional knockout mice reached full term but died within one week of birth. Further analyses revealed that Tfr1-deficient HSC had impaired development of all hematopoietic progenitors except thrombocytes and B lymphocytes. In addition, Tfr1-deficient cells had cellular iron deficiency, which blocked the proliferation and differentiation of hematopoietic precursor cells, attenuated the commitment of hematopoietic lineages, and reduced the regeneration potential of HSC. Notably, hemin rescued the colony-forming capacity of Tfr1-deficient HSC, whereas expressing a mutant Tfr1 that lacks the protein's iron-transporting capacity failed to rescue hematopoiesis. These findings provide direct evidence that Tfr1 is essential for hematopoiesis through binding diferric transferrin to supply iron to cells.


Assuntos
Ferro , Receptores da Transferrina , Animais , Transporte Biológico , Hematopoese/genética , Ferro/metabolismo , Camundongos , Camundongos Knockout , Receptores da Transferrina/genética , Transferrina/metabolismo
5.
Int J Cancer ; 143(7): 1595-1603, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29696630

RESUMO

Numerous studies have suggested that excess body weight is associated with increased cancer risk. To examine this putative association, we performed a systematic review and quantitative meta-analysis of cohort studies reporting body mass index (BMI) and the risk of 23 cancer types. PubMed, Embase, and Web of Science were searched for cohort studies, yielding 325 articles with 1,525,052 cases. Strong positive associations were observed between BMI and endometrial cancer (RR: 1.48), esophageal adenocarcinoma (RR: 1.45), and kidney cancer (RR: 1.20); weaker associations (RR < 1.20) were also found for several other cancer types. Interestingly, we found significant inverse associations between BMI and oral cavity (RR: 0.93), lung (RR: 0.91), premenopausal breast (RR: 0.95), and localized prostate (RR: 0.97) cancers. A male-specific association was found for colorectal cancer (p = 0.023), and a female-specific association was found for cancer in brain (p = 0.025) or kidney (p = 0.035). With respect to geography, the strongest positive association was found for total cancer in North America (p = 0.038). This comprehensive meta-analysis provides epidemiological evidence supporting the association between BMI and cancer risk. These findings can be used to drive public policies and to help guide personalized medicine in order to better manage body weight, thereby reducing the risk of developing obesity-related cancer.


Assuntos
Índice de Massa Corporal , Peso Corporal/fisiologia , Neoplasias/epidemiologia , Adulto , Feminino , Humanos , Estilo de Vida , Masculino , América do Norte/epidemiologia , Obesidade/epidemiologia , Fatores de Risco
6.
J Cell Physiol ; 233(9): 7268-7278, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29600572

RESUMO

Hemochromatosis is prevalent and often associated with high rates of morbidity and mortality worldwide. The safe alternative iron-reducing approaches are urgently needed in order to better control iron overload. Our unbiased vitamin screen for modulators of hepcidin, a master iron regulatory hormone, identifies adenine (vitamin B4) as a potent hepcidin agonist. Adenine significantly induced hepcidin mRNA level and promoter activity activation in human cell lines, possibly through BMP/SMAD pathway. Further studies in mice validated the effect of adenine on hepcidin upregulation. Consistently, adenine dietary supplement in mice led to an increase of hepatic hepcidin expression compared with normal diet-fed mice via BMP/SMAD pathway. Notably, adenine-rich diet significantly ameliorated iron overload accompanied by the enhanced hepcidin expression in both high iron-fed mice and in Hfe-/- mice, a murine model of hereditary hemochromatosis. To further validate this finding, we selected pharmacological inhibitors against BMP (LDN193189). We found LDN193189 strongly blocked the hepcidin induction by adenine. Moreover, we uncovered an essential role of cAMP/PKA-dependent axis in triggering adenine-induced hepcidin expression in primary hepatocytes by using 8 br cAMP, a cAMP analog, and H89, a potent inhibitor for PKA signaling. These findings suggest a potential therapeutic role of adenine for hereditary hemochromatosis.


Assuntos
Adenina/farmacologia , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Hepcidinas/metabolismo , Sobrecarga de Ferro/metabolismo , Fígado/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular Tumoral , Dieta , Modelos Animais de Doenças , Proteína da Hemocromatose/deficiência , Proteína da Hemocromatose/metabolismo , Humanos , Ferro/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Transdução de Sinais , Proteínas Smad/metabolismo , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos , Vitaminas/metabolismo
7.
J Cell Mol Med ; 22(6): 3035-3044, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29575577

RESUMO

To maintain iron homoeostasis, the iron regulatory hormone hepcidin is tightly controlled by BMP-Smad signalling pathway, but the physiological role of Smad7 in hepcidin regulation remains elusive. We generated and characterized hepatocyte-specific Smad7 knockout mice (Smad7Alb/Alb ), which showed decreased serum iron, tissue iron, haemoglobin concentration, up-regulated hepcidin and increased phosphor-Smad1/5/8 levels in both isolated primary hepatocytes and liver tissues. Increased levels of hepcidin lead to reduced expression of intestinal ferroportin and mild iron deficiency anaemia. Interestingly, we found no difference in hepcidin expression or phosphor-Smad1/5/8 levels between iron-challenged Smad7Alb/Alb and Smad7flox/flox , suggesting other factors assume the role of iron-induced hepcidin regulation in Smad7 deletion. We performed RNA-seq to identify differentially expressed genes in the liver. Significantly up-regulated genes were then mapped to pathways, revealing TGF-ß signalling as one of the most relevant pathways, including the up-regulated genes Smad6, Bambi and Fst (Follistatin). We found that Smad6 and Bambi-but not Follistatin-are controlled by the iron-BMP-Smad pathway. Overexpressing Smad6, Bambi or Follistatin in cells significantly reduced hepcidin expression. Smad7 functions as a key regulator of iron homoeostasis by negatively controlling hepcidin expression, and Smad6 and Smad7 have non-redundant roles. Smad6, Bambi and Follistatin serve as additional inhibitors of hepcidin in the liver.


Assuntos
Hepcidinas/genética , Fígado/metabolismo , Proteína Smad7/genética , Fator de Crescimento Transformador beta/genética , Animais , Folistatina/genética , Regulação da Expressão Gênica/genética , Hemoglobinas/genética , Hemoglobinas/metabolismo , Hepatócitos/metabolismo , Hepcidinas/metabolismo , Humanos , Ferro/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Análise de Sequência de RNA , Transdução de Sinais , Proteína Smad6/genética , Proteína Smad7/deficiência
8.
Proc Natl Acad Sci U S A ; 114(49): 12940-12945, 2017 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-29180421

RESUMO

Zn plays a key role in controlling macrophage function during an inflammatory event. Cellular Zn homeostasis is regulated by two families of metal transporters, the SLC39A family of importers and the SLC30A family of exporters; however, the precise role of these transporters in maintaining macrophage function is poorly understood. Using macrophage-specific Slc39a10-knockout (Slc39a10fl/fl;LysM-Cre+ ) mice, we found that Slc39a10 plays an essential role in macrophage survival by mediating Zn homeostasis in response to LPS stimulation. Compared with Slc39a10fl/fl mice, Slc39a10fl/fl;LysM-Cre+ mice had significantly lower mortality following LPS stimulation as well as reduced liver damage and lower levels of circulating inflammatory cytokines. Moreover, reduced intracellular Zn concentration in Slc39a10fl/fl;LysM-Cre+ macrophages led to the stabilization of p53, which increased apoptosis upon LPS stimulation. Concomitant knockout of p53 largely rescued the phenotype of Slc39a10fl/fl;LysM-Cre+ mice. Finally, the phenotype in Slc39a10fl/fl;LysM-Cre+ mice was mimicked in wild-type mice using the Zn chelator TPEN and was reversed with Zn supplementation. Taken together, these results suggest that Slc39a10 plays a role in promoting the survival of macrophages through a Zn/p53-dependent axis in response to inflammatory stimuli.


Assuntos
Proteínas de Transporte de Cátions/fisiologia , Macrófagos/fisiologia , Sepse/imunologia , Animais , Apoptose/imunologia , Sobrevivência Celular , Citocinas/sangue , Humanos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Knockout , Sepse/metabolismo , Sobreviventes , Proteína Supressora de Tumor p53/metabolismo , Zinco/metabolismo
9.
Eur J Cancer ; 51(18): 2820-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26589974

RESUMO

BACKGROUND: The associations between dietary factors and gastric cancer risk have been analysed by many studies, but with inconclusive results. We conducted a meta-analysis of prospective studies to systematically investigate the associations. METHODS: Relevant studies were identified through searching Medline, Embase, and Web of Science up to June 30, 2015. We included prospective cohort studies of intake of dietary factors with risk estimates and 95% confidence intervals for gastric cancer. RESULTS: Seventy-six prospective cohort studies were eligible and included in the analysis. We ascertained 32,758 gastric cancer cases out of 6,316,385 participants in relations to intake of 67 dietary factors, covering a wide ranging of vegetables, fruit, meat, fish, salt, alcohol, tea, coffee, and nutrients, during 3.3 to 30 years of follow-up. Evidence from this study indicates that consumption of total fruit and white vegetables, but not total vegetables, was inversely associated with gastric cancer risk. Both fruit and white vegetables are rich sources of vitamin C, which showed significant protective effect against gastric cancer by our analysis too. Furthermore, we found concordant positive associations between high-salt foods and gastric cancer risk. In addition, a strong effect of alcohol consumption, particularly beer and liquor but not wine, on gastric cancer risk was observed compared with nondrinkers. Dose-response analysis indicated that risk of gastric cancer was increased by 12% per 5 g/day increment of dietary salt intake or 5% per 10 g/day increment of alcohol consumption, and that a 100 g/day increment of fruit consumption was inversely associated with 5% reduction of risk. CONCLUSION: This study provides comprehensive and strong evidence that there are a number of protective and risk factors for gastric cancer in diet. Our findings may have significant public health implications with regard to prevention of gastric cancer and provide insights into future cohort studies and the design of related clinical trials.


Assuntos
Dieta , Estilo de Vida , Neoplasias Gástricas/epidemiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Dieta/efeitos adversos , Comportamento Alimentar , Frutas , Humanos , Estado Nutricional , Razão de Chances , Estudos Prospectivos , Fatores de Proteção , Medição de Risco , Fatores de Risco , Cloreto de Sódio na Dieta/efeitos adversos , Neoplasias Gástricas/diagnóstico , Verduras
10.
Toxicol Sci ; 147(2): 436-45, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26160115

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous persistent environmental pollutants which are primarily formed from the incomplete combustion of organic materials. Many potential sources of human exposure to PAHs exist, including daily exposures from the ambient environment or occupational settings. PAHs have been found to cause harmful effects on human health. Here, we evaluated the adverse effects of pyrene, a common PAH, on the liver. The present study demonstrates that pyrene is able to activate mouse constitutive androstane receptor (CAR). CAR protein, as measured by Western blot analysis, was observed to translocate into the nucleus from the cytoplasm in mouse liver after exposure to pyrene. Utilizing CAR null mice, we identified that CAR mediates pyrene-induced hepatotoxicity. Increased relative liver weight, hepatocellular hypertrophy, and elevated serum alanine aminotransferase levels were found in wild-type but not CAR null mice after orally administered pyrene. We further show that pyrene induced the expression of mouse liver metabolism enzymes including CYP2B10, CYP3A11, GSTm1, GSTm3, and SULT1A1, and caused hepatic glutathione depletion in wild-type but not CAR null mice. Moreover, by luciferase reporter assay and quantitative real-time PCR analysis, pyrene was found to be a potential inducer of CYP2B6 expression via activation of human CAR in HepG2 cells and human primary hepatocytes. Our observations suggest that pyrene is a novel CAR activator and that CAR is essential for mediating pyrene-induced liver injury.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Pirenos/toxicidade , Receptores Citoplasmáticos e Nucleares/agonistas , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Alanina Transaminase/sangue , Animais , Western Blotting , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Receptor Constitutivo de Androstano , Citocromo P-450 CYP2B6/metabolismo , Glutationa/análise , Células Hep G2/efeitos dos fármacos , Células Hep G2/metabolismo , Humanos , Fígado/química , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Fígado/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pirenos/farmacologia , Receptores Citoplasmáticos e Nucleares/análise , Receptores Citoplasmáticos e Nucleares/fisiologia
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