Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Adv Sci (Weinh) ; 10(7): e2203528, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36642839

RESUMO

Metabolites are important for cell fate determination. Fructose-1,6-bisphosphate (F1,6P) is the rate-limiting product in glycolysis and the rate-limiting substrate in gluconeogenesis. Here, it is discovered that the nuclear-accumulated F1,6P impairs cancer cell viability by directly binding to high mobility group box 1 (HMGB1), the most abundant non-histone chromosome structural protein with paradoxical roles in tumor development. F1,6P disrupts the association between the HMGB1 A-box and C-tail by targeting K43/K44 residues, inhibits HMGB1 oligomerization, and stabilizes P53 protein by increasing P53-HMGB1 interaction. Moreover, F1,6P lowers the affinity of HMGB1 for DNA and DNA adducts, which sensitizes cancer cells to chemotherapeutic drug(s)-induced DNA replication stress and DNA damage. Concordantly, F1,6P resensitizes cancer cells with chemotherapy resistance, impairs tumor growth and enhances chemosensitivity in mice, and impedes the growth of human tumor organoids. These findings reveal a novel role for nuclear-accumulated F1,6P and underscore the potential utility of F1,6P as a drug for cancer therapy.


Assuntos
Frutosedifosfatos , Proteína HMGB1 , Neoplasias , Animais , Humanos , Camundongos , Dano ao DNA , Glicólise , Proteína HMGB1/química , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Neoplasias/metabolismo , Proteína Supressora de Tumor p53/genética , Frutosedifosfatos/metabolismo
2.
Nat Commun ; 12(1): 1940, 2021 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-33782411

RESUMO

Metabolic enzymes and metabolites display non-metabolic functions in immune cell signalling that modulate immune attack ability. However, whether and how a tumour's metabolic remodelling contributes to its immune resistance remain to be clarified. Here we perform a functional screen of metabolic genes that rescue tumour cells from effector T cell cytotoxicity, and identify the embryo- and tumour-specific folate cycle enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2). Mechanistically, MTHFD2 promotes basal and IFN-γ-stimulated PD-L1 expression, which is necessary for tumourigenesis in vivo. Moreover, IFN-γ stimulates MTHFD2 through the AKT-mTORC1 pathway. Meanwhile, MTHFD2 drives the folate cycle to sustain sufficient uridine-related metabolites including UDP-GlcNAc, which promotes the global O-GlcNAcylation of proteins including cMYC, resulting in increased cMYC stability and PD-L1 transcription. Consistently, the O-GlcNAcylation level positively correlates with MTHFD2 and PD-L1 in pancreatic cancer patients. These findings uncover a non-metabolic role for MTHFD2 in cell signalling and cancer biology.


Assuntos
Aminoidrolases/genética , Antígeno B7-H1/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Metilenotetra-Hidrofolato Desidrogenase (NADP)/genética , Enzimas Multifuncionais/genética , Neoplasias Pancreáticas/genética , Processamento de Proteína Pós-Traducional , Linfócitos T Citotóxicos/imunologia , Aminoidrolases/antagonistas & inibidores , Aminoidrolases/imunologia , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/imunologia , Carcinogênese/imunologia , Carcinogênese/patologia , Linhagem Celular Tumoral , Embrião de Mamíferos , Fibroblastos/imunologia , Fibroblastos/patologia , Ácido Fólico/imunologia , Ácido Fólico/metabolismo , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/imunologia , Metilenotetra-Hidrofolato Desidrogenase (NADP)/antagonistas & inibidores , Metilenotetra-Hidrofolato Desidrogenase (NADP)/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Nus , Enzimas Multifuncionais/antagonistas & inibidores , Enzimas Multifuncionais/imunologia , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/imunologia , Proteínas Proto-Oncogênicas c-myc/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/imunologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/imunologia , Transdução de Sinais , Linfócitos T Citotóxicos/patologia , Carga Tumoral , Evasão Tumoral , Uridina Difosfato N-Acetilglicosamina/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Oncogenesis ; 9(2): 21, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060258

RESUMO

The protein O-GlcNAcylation catalysed by O-GlcNAc transferase (OGT) is tightly regulated by glucose availability. It is upregulated and essential for tumor cell proliferation under hypoxic conditions. However, the mechanism behind is still unclear. Here, we showed that the glycolytic regulator 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB3), which also promotes cell cycle progression in the nucleus, was O-GlcNAcylated in response to hypoxia. The O-GlcNAcylation of PFKFB3 could compete phosphorylation by hypoxia-activated ERK at the same modification site Ser172. Phosphorylated PFKFB3 could interact with the protein G3BP2 and retain in the cytosol; this in turn led to the accumulation of hypoxia-induced-P27 in the nucleus resulting in the cell cycle arrest. Such a pathway was compromised by high level of PFKFB3 O-GlcNAcylation in tumor cells contributing to cell cycle progression. Consistently, the PFKFB3-Ser172 phosphorylation level inversely correlated with the OGT level in pancreatic cancer patients. Our findings uncovered an O-GlcNAcylation mediated mechanism to promote tumor cell proliferation under metabolic stress, linking the aberrant OGT activity to tumorigenesis in pancreatic cancer.

4.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 34(2): 164-168, 2018 Feb 08.
Artigo em Chinês | MEDLINE | ID: mdl-29926683

RESUMO

OBJECTIVES: To investigate the effects of Astragaloside IV (AST) on diastolic function of rat thoracic aorta rings which was injured by microvesicles derived from hypoxia/reoxygenation (H/R)-treated human umbilical vein endothelial cells (HUVECs), and the mechanism of AST. METHODS: H/R-induced endothelial microvesicles (H/R-EMVs) were generated from cultured HUVECs in vitro under the condition of hypoxia for 12 hour/Reoxygenation for 4 hour, H/R-EMVs were stored in D-Hank's solution. Male Wistar rats were underwent thoracotomy, the thoracic aorta with intact endothelium were carefully removed and cut into 3~4 mm rings. The experiment was divided into six groups. H/R-EMVs group:thoracic aortic rings of rats were incubated in culture medium and treated with H/R-EMVs in a final concentration of 10µg/ml; different doses of AST groups:thoracic aortic rings of rats were treated with 10, 20, 40, 60 mg/L AST co-incubated with 10µg/ml H/R-EMVs respectively; control group were treated with the same volume of D-Hank's solution. Duration of incubation was 4 h, each group was tested in five replicate aortic rings. Effects of AST on endothelium-dependent relaxation were detected. The production of nitric oxide (NO) and the level of endothelial NO synthase (eNOS), phosphorylated eNOS (p-eNOS, Ser-1177), serine/threonine kinase (Akt), phosphorylated Akt (p-Akt, Ser-473), extracellular regulated protein kinases (ERK1/2) and phosphorylated ERK1/2 (p-ERK1/2, Thr202/Tyr204) of rat thoracic aortic rings were detected. RESULTS: Tenµg/ml H/R-EMVs could impaire the relaxation of rat thoracic aortic rings significantly (P<0.01). Compared with H/R-EMVs group, relaxation of rat thoracic aortic rings was increased by 20, 40 and 60 mg/L AST in a concentration-dependent manner (P<0.01), the level of NO production was also enhanced (P<0.05, P<0.01). The level of t-eNOS, t-Akt and ERK1/2 was not changed, but the level of p-eNOS, p-Akt and p-ERK1/2 increased by the treatment with AST (P<0.01). CONCLUSIONS: AST could effectively ameliorate endotheliumdependent relaxation of rat thoracic aortic rings impaired by H/R-EMVs in a concentration-dependent manner, the mechanism might involve the increase in production of NO, and the protein level of p-eNOS, p-Akt and p-ERK1/2.


Assuntos
Aorta Torácica/efeitos dos fármacos , Micropartículas Derivadas de Células/patologia , Saponinas/farmacologia , Triterpenos/farmacologia , Vasodilatação , Animais , Células Endoteliais da Veia Umbilical Humana , Humanos , Técnicas In Vitro , Sistema de Sinalização das MAP Quinases , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...