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1.
J Cancer Res Clin Oncol ; 145(10): 2433-2444, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485767

RESUMO

PURPOSE: The clinical importance of cancer stem cells (CSCs) in head and neck squamous cell carcinoma (HNSCC) is well recognized. However, a reliable method for the detection of functioning CSC has not yet been established. We hypothesized that YAP1, a transcriptional coactivator, and SOX2, a master transcription factor of SCC, may cooperatively induce stemness through transcriptional reprogramming. METHODS: We immunohistochemically examined the expression of SOX2 and YAP1 in the CD44 variant 9 (CD44v9)-positive invasion front. A CSC-inducible module was identified through a combination of siRNAs and sphere formation assays. YAP1 and SOX2 interactions were analyzed in vitro. RESULTS: The triple overexpression of SOX2, YAP1, and CD44v9 was significantly associated with poor prognosis. TCGA data revealed that the CSC-inducible module, which was related to EMT and angiogenesis, was significantly correlated with poor prognosis. The KLF7 expression, representatively chosen from the module, also correlated with poor prognosis and was essential for sphere formation and CSC propagation. Sphere stress-activated YAP1 enhanced SOX2 activity. CONCLUSIONS: The stress-triggered activation of YAP1/SOX2 transcriptionally reprograms HNSCC for the acquisition of stemness. Triple SOX2, YAP1, and CD44v9 immunostaining assays may be useful for the selection of high-risk patients with functioning CSCs, and YAP1 targeting may lead to the development of a CSC-targeting therapy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Células-Tronco Neoplásicas/metabolismo , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Estresse Fisiológico , Ativação Transcricional , Biomarcadores , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Células-Tronco Neoplásicas/patologia , RNA Interferente Pequeno/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Estresse Fisiológico/genética , Fatores de Transcrição
2.
J Clin Pathol ; 72(11): 778-782, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31473630

RESUMO

SF3B1 is the largest subunit of the Spliceosome Factor 3b (SF3B) complex and part of the U2 small nuclear ribosomal protein. It functions as an important part of spliceosomal assembly, converting precursor messenger RNA (mRNA) to mRNA ready for ribosomal translation. Mutations of SF3B1 are commonly seen in myelodysplastic syndromes with ring sideroblasts (MDS-RS)and MDS/myeloproliferative neoplasm (MPN-RS-T). These mutations are typically heterozygous missense substitutions, of which, 55% involve K700E. MDS-RS and MDS/MPN-RS-T usually carry a more favourable prognosis than other subtypes of MDS. SF3B1 itself does not influence survival in these conditions, but does correlate with increased thrombotic risk. Mutated SF3B1 is present in 9%-15% of chronic lymphocytic leukaemia cases and on its own correlates with improved responsiveness to ibrutinib, but is associated with additional adverse genetic abnormalities including TP53 and ATM mutations, which traditionally confer adverse outcomes.


Assuntos
Biomarcadores Tumorais/genética , Eritroblastos/patologia , Leucemia Linfocítica Crônica de Células B/genética , Mutação , Síndromes Mielodisplásicas/genética , Fosfoproteínas/genética , Fatores de Processamento de RNA/genética , Predisposição Genética para Doença , Humanos , Leucemia Linfocítica Crônica de Células B/metabolismo , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Linfocítica Crônica de Células B/terapia , Síndromes Mielodisplásicas/metabolismo , Síndromes Mielodisplásicas/patologia , Síndromes Mielodisplásicas/terapia , Fenótipo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Prognóstico , Conformação Proteica , Fatores de Processamento de RNA/química , Fatores de Processamento de RNA/metabolismo , Spliceossomos/genética , Spliceossomos/metabolismo , Relação Estrutura-Atividade
3.
Nature ; 574(7776): 63-68, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31554967

RESUMO

The gp130 receptor cytokines IL-6 and CNTF improve metabolic homeostasis but have limited therapeutic use for the treatment of type 2 diabetes. Accordingly, we engineered the gp130 ligand IC7Fc, in which one gp130-binding site is removed from IL-6 and replaced with the LIF-receptor-binding site from CNTF, fused with the Fc domain of immunoglobulin G, creating a cytokine with CNTF-like, but IL-6-receptor-dependent, signalling. Here we show that IC7Fc improves glucose tolerance and hyperglycaemia and prevents weight gain and liver steatosis in mice. In addition, IC7Fc either increases, or prevents the loss of, skeletal muscle mass by activation of the transcriptional regulator YAP1. In human-cell-based assays, and in non-human primates, IC7Fc treatment results in no signs of inflammation or immunogenicity. Thus, IC7Fc is a realistic next-generation biological agent for the treatment of type 2 diabetes and muscle atrophy, disorders that are currently pandemic.


Assuntos
Receptor gp130 de Citocina/metabolismo , Citocinas/síntese química , Citocinas/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Ligação Competitiva , Citocinas/química , Diabetes Mellitus Tipo 2/metabolismo , Desenho de Drogas , Fígado Gorduroso/prevenção & controle , Teste de Tolerância a Glucose , Humanos , Hiperglicemia/tratamento farmacológico , Hiperglicemia/metabolismo , Incretinas/metabolismo , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Masculino , Camundongos , Músculo Esquelético/efeitos dos fármacos , Obesidade/metabolismo , Pâncreas/metabolismo , Fosfoproteínas/metabolismo , Engenharia de Proteínas , Receptores de Interleucina-6/metabolismo , Transdução de Sinais , Fatores de Transcrição , Ganho de Peso/efeitos dos fármacos
4.
Mol Biol (Mosk) ; 53(4): 663-673, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31397440

RESUMO

Malignant cutaneous melanoma (CM) is an extremely aggressive cancer characterized by a high level of metastatic activity and unfavorable prognosis due to a high incidence of relapses, as well as resistance to standard chemotherapy. Cutaneous melanoma accounts for 80% of deaths from malignant skin tumors. Nucleolin/C23 and nucleophosmin/B23, which constitute altogether ~70% of the nucleolus volume, are promising targets for molecular therapy of melanoma. These proteins perform many important functions in the cell, so disruption of the NCL and/or NPM gene structure and abnormal expression of the C23 and B23 proteins they encode, can lead to unlimited cell proliferation and progression of a tumor. Therefore, investigation of the structure and expression of these genes is a topical problem, which is important for understanding the mechanisms of CM carcinogenesis and for the development of new therapeutic approaches. This paper describes new NCL and NPM polymorphisms, as well as the levels of C23 and B23 expression in normal tissues, CM and mucosal melanoma.


Assuntos
Melanoma/genética , Melanoma/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Nucléolo Celular/química , Nucléolo Celular/metabolismo , Proliferação de Células , Humanos , Melanoma/tratamento farmacológico , Terapia de Alvo Molecular , Proteínas Nucleares/biossíntese , Proteínas Nucleares/química , Fosfoproteínas/biossíntese , Fosfoproteínas/química , Polimorfismo Genético , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/química , Neoplasias Cutâneas/tratamento farmacológico
5.
Cancer Sci ; 110(10): 3145-3156, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31393050

RESUMO

Yes-associated protein (YAP) is a component of the canonical Hippo signaling pathway that is known to play essential roles in modulating organ size, development, and tumorigenesis. Activation or upregulation of YAP1, which contributes to cancer cell survival and chemoresistance, has been verified in different types of human cancers. However, the molecular mechanism of YAP1 upregulation in cancer is still unclear. Here we report that the E3 ubiquitin ligase STUB1 ubiquitinates and destabilizes YAP1, thereby inhibiting cancer cell survival. Low levels of STUB1 expression were correlated with increased protein levels of YAP1 in human gastric cancer cell lines and patient samples. Moreover, we revealed that STUB1 ubiquitinates YAP1 at the K280 site by K48-linked polyubiquitination, which in turn increases YAP1 turnover and promotes cellular chemosensitivity. Overall, our study establishes YAP1 ubiquitination and degradation mediated by the E3 ligase STUB1 as an important regulatory mechanism in gastric cancer, and provides a rationale for potential therapeutic interventions.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Neoplasias Gástricas/patologia , Ubiquitina-Proteína Ligases/metabolismo , Animais , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Células HEK293 , Humanos , Lisina/metabolismo , Camundongos , Transplante de Neoplasias , Estabilidade Proteica , Proteólise , Transdução de Sinais , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Fatores de Transcrição , Ubiquitinação
6.
Hypertension ; 74(4): 936-946, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31378107

RESUMO

Endothelial cells regulate vascular tone by producing both relaxing and contracting factors to control the local blood flow. Hypertension is a common side effect of mTORC1 (mammalian target of rapamycin complex 1) inhibitors. However, the role of endothelial mTORC1 in hypertension remains elusive. The present study aimed to determine the role of endothelial mTORC1 in Ang II (angiotensin II)-induced hypertension and the underlying mechanism. Endothelial mTORC1 activity was increased by Ang II both in vitro and in vivo. Blood pressure was higher in Tie-2-Cre-mediated regulatory associated protein of mTOR (mammalian target of rapamycin; Raptor) heterozygous-deficient (Tie2Cre-RaptorKD) mice than control mice both before and after Ang II infusion. Acetylcholine-evoked endothelium-dependent relaxation of mesenteric arteries was impaired in Tie2Cre-RaptorKD mice. Treatment with indomethacin or a specific COX (cyclooxygenase)-2 inhibitor, NS-398, but not L-NG-nitroarginine methyl ester reduced endothelium-dependent relaxation in Raptorflox/- mice to a similar extent as in Tie2Cre-RaptorKD mice. Metabolomic profiling revealed that the plasma content of prostaglandin E2 was reduced in Tie2Cre-RaptorKD mice with or without Ang II infusion. In endothelial cells, reduction of the protein level of YAP (yes-associated protein) with siRNA-mediated RPTOR deficiency was autophagy dependent and transcriptionally regulated the expression of COX-2 and mPGES-1 (microsomal prostaglandin E synthase-1). Hence, overexpression of YAP in endothelial cells enhanced the mRNA and protein levels of COX-2 and mPGES-1 and reversed the endothelial dysfunction and hypertension in Tie2Cre-RaptorKD mice. The present results demonstrate that suppression of mTORC1 activity in endothelial cells reduces prostaglandin E2 production and causes hypertension by reducing YAP-mediated COX-2/mPGES-1 expression.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Pressão Sanguínea/fisiologia , Endotélio Vascular/metabolismo , Hipertensão/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fosfoproteínas/metabolismo , Transdução de Sinais/fisiologia , Angiotensina II , Animais , Pressão Sanguínea/efeitos dos fármacos , Proteínas de Ciclo Celular , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Dinoprostona/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/efeitos dos fármacos , Hipertensão/induzido quimicamente , Indometacina/farmacologia , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/metabolismo , Camundongos , Prostaglandina-E Sintases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatação/fisiologia
7.
Toxicol Lett ; 314: 53-62, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31319113

RESUMO

Benzyl butyl phthalate (BBP) is a widely used plasticizer and has raised public health concerns. Here, we report the effects of BBP on the testis development during rat puberty. BBP (0, 10, 100 or 1000 mg/kg) was gavaged to 35-day-old male Sprague Dawley rats for 21 days. The serum testosterone levels, Leydig cell number, the expressions of Leydig and Sertoli cell genes and proteins were measured. The in vitro effects on steroidogenesis and gene expression in immature Leydig cells were observed. BBP significantly increased serum testosterone level at 10 mg/kg but lowered its level at 1000 mg/kg without affecting serum luteinizing hormone and follicle-stimulating hormone levels. BBP increased Leydig cell number at all doses but inhibited steroidogenic capacity per Leydig cell at 1000 mg/kg. BBP significantly increased the ratio of phosphos-AKT2 (pAKT2)/AKT2, and phosphos-ERK1/2 (pERK1/2)/ERK1/2 in the testis. Mono-benzyl phthalate (the metabolite of BBP) inhibited steroidogenesis but BBP did not affect androgen production in immature Leydig cells in vitro. In conclusion, BBP non-linearly regulates Leydig cell development by increasing Leydig cell number but inhibiting steroidogenesis.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Intersticiais do Testículo/efeitos dos fármacos , Ácidos Ftálicos/toxicidade , Plastificantes/toxicidade , Desenvolvimento Sexual/efeitos dos fármacos , Testosterona/biossíntese , Fatores Etários , Animais , Relação Dose-Resposta a Droga , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/patologia , Masculino , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Receptores Depuradores Classe B/genética , Receptores Depuradores Classe B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Testosterona/sangue
8.
Science ; 365(6454)2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31320558

RESUMO

DNA viruses typically eject genomic DNA into the nuclei of host cells after entry. It is unclear, however, how nuclear pathogen-derived DNA triggers innate immune responses. We report that heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) recognizes pathogenic DNA and amplifies interferon-α/ß (IFN-α/ß) production. Upon DNA virus infection, nuclear-localized hnRNPA2B1 senses viral DNA, homodimerizes, and is then demethylated at arginine-226 by the arginine demethylase JMJD6. This results in hnRNPA2B1 translocation to the cytoplasm where it activates the TANK-binding kinase 1-interferon regulatory factor 3 (TBK1-IRF3) pathway, leading to IFN-α/ß production. Additionally, hnRNPA2B1 facilitates N 6-methyladenosine (m6A) modification and nucleocytoplasmic trafficking of CGAS, IFI16, and STING messenger RNAs. This, in turn, amplifies the activation of cytoplasmic TBK1-IRF3 mediated by these factors. Thus, hnRNPA2B1 plays important roles in initiating IFN-α/ß production and enhancing stimulator of interferon genes (STING)-dependent cytoplasmic antiviral signaling.


Assuntos
Núcleo Celular/imunologia , Núcleo Celular/virologia , Infecções por Vírus de DNA/imunologia , DNA Viral/imunologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/metabolismo , Imunidade Inata , Adenosina/análogos & derivados , Adenosina/metabolismo , Animais , Citoplasma/metabolismo , Células HEK293 , Herpesvirus Humano 1/imunologia , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Humanos , Fator Regulador 3 de Interferon , Interferon-alfa/metabolismo , Interferon beta/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas Nucleares/metabolismo , Nucleotidiltransferases/metabolismo , Fosfoproteínas/metabolismo , Transporte Proteico , Proteínas Serina-Treonina Quinases/metabolismo , Células RAW 264.7
9.
Zhonghua Gan Zang Bing Za Zhi ; 27(7): 572-577, 2019 Jul 20.
Artigo em Chinês | MEDLINE | ID: mdl-31357789

RESUMO

The transcriptional coactivator Yes-associated protein (YAP) is involved in the regulation of various cellular physiological activities and plays an important role in controlling the size of tissues and organs for maintaining the homeostasis. YAP not only affects the transcriptional expression of its downstream target genes, but also interacts with multiple signaling pathways to form complex regulatory networks to perform specific biological functions. In addition to Hippo signaling pathway mediated protein phosphorylation, the regulatory mechanisms of YAP activity also takes part in multiple fields. YAP activity alteration can affect the morphological characteristics and physiological functions of liver tissue, and participate in the occurrence and development of liver diseases, such as liver fibrosis and primary liver cancer. This paper mainly discusses the close relationship between YAP and liver pathophysiology, in order to provide reference for further exploring its potential application in molecular targeted therapy of liver diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Fosfoproteínas/metabolismo , Transdução de Sinais , Humanos , Fatores de Transcrição
10.
Life Sci ; 233: 116694, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31351970

RESUMO

AIMS: The hypoxia-stimulated response of the endocrine system depends on the kind and duration of hypoxia. Hypoxia has been reported to stimulate testosterone (T) production in rats, but the mechanisms remain to be investigated. MATERIALS AND METHODS: Male rats were divided into two groups. The rats exposed to chronic intermittent hypoxia (CIH) at 8 h/day were housed in a hypoxic chamber (12% O2) for 14 days. Normoxic rats were used as control animals. T was measured after challenging the rat Leydig cells (LCs) with different stimulators, including hCG (0.01 IU/ml), forskolin (10-5 M), 8-bromo-cAMP (10-4 M), A23187 (10-5 M), cyclopiazonic acid (10-4 M), and androstenedione (10-8 M). Meanwhile, the LCs were incubated with trilostane (10-5 M) and/or 25-OH-hydroxycholesterol (10-5 M); thereafter the media were collected for pregnenolone assay. KEY FINDINGS: In the CIH group, plasma T levels were increased, but the serum luteinizing hormone (LH) was decreased. Furthermore, at several time intervals after hCG injection, plasma T levels were higher in the CIH group. The evoked-release of T and pregnenolone were significantly increased in the CIH group. Compared with the normoxic group, the CIH group had higher mRNA and protein expression levels of the LH receptor and CYP11A1 but not StAR. The plasma and testicular microvasculature VEGF levels were increased in the CIH group. The testicular vessel distribution was more obvious in CIH rats. SIGNIFICANCE: CIH-induced T secretion might be partially mediated by mechanisms involving the induction of LH receptor expression, testicular angiogenesis, CYP11A1 activity, 17ß-HSD activity, and calcium-related pathway.


Assuntos
Hipóxia Celular/fisiologia , Colforsina/farmacologia , Células Intersticiais do Testículo/metabolismo , Testosterona/metabolismo , Animais , Células Cultivadas , Enzima de Clivagem da Cadeia Lateral do Colesterol/genética , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/efeitos dos fármacos , Masculino , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores do LH/genética , Receptores do LH/metabolismo , Vasodilatadores/farmacologia
11.
Eur J Pharm Biopharm ; 142: 473-479, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31325486

RESUMO

Nucleic acid aptamers have emerged as an attractive class of carrier molecules due to their ability to bind with high affinity to specific ligands; their high chemical flexibility; as well as tissue penetration capability. RNA G-quadruplex (rG4) sequences have been described as structures with high stability and selectivity towards cancer cells. Recently, precursor microRNAs (pre-miRNAs) have been described as new G4 forming molecules. Surface nucleolin (NCL) is a known target of aptamer G4 AS1411 and is overexpressed on prostate cancer cells when compared with normal cells. We have shown that the sequence 5' GGGAGGGAGGGACGGG 3' found in pre-miR-149 forms a rG4 parallel structure, which can bind NCL. Also, another rG4 sequence with a longer loop was evaluated in terms of G4 formation, stabilization and binding affinity to NCL. Both rG4s sequences were studied as supramolecular carriers for the cancer-selective delivery of acridine ligand C8. The rG4s-C8 complexes showed high affinity (KD = 10-6 M) and stabilization (Tm > 30 °C). The affinity of the rG4s-C8 complexes against NCL was in the low nanomolar range, indicating that C8 did not affect NCL binding. Noteworthy, the short loop rG4-C8 complex showed selective antiproliferative effects in prostate cancer cells when compared with normal prostatic cells. The stability and nuclease resistance of rG4 and rG4-C8 complex were evaluated in biological conditions and revealed the maintenance of G4 structure and complex stability. Furthermore, confocal microscopy studies confirmed the potential of rG4s-C8 complexes in the targeting of prostate cancer cells. Overall, it is here demonstrated that the rG4 found in pre-miR-149 can be used as a cancer-selective delivery carrier of C8 to prostate cancer cells.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Portadores de Fármacos/química , MicroRNAs/química , MicroRNAs/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Quadruplex G , Humanos , Ligantes , Masculino , Oligodesoxirribonucleotídeos/química , Oligonucleotídeos/química , Células PC-3 , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo
12.
Physiol Rev ; 99(4): 1655-1699, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31313981

RESUMO

Integrins are heterodimeric cell surface receptors ensuring the mechanical connection between cells and the extracellular matrix. In addition to the anchorage of cells to the extracellular matrix, these receptors have critical functions in intracellular signaling, but are also taking center stage in many physiological and pathological conditions. In this review, we provide some historical, structural, and physiological notes so that the diverse functions of these receptors can be appreciated and put into the context of the emerging field of mechanobiology. We propose that the exciting journey of the exploration of these receptors will continue for at least another new generation of researchers.


Assuntos
Adesão Celular , Membrana Celular/metabolismo , Matriz Extracelular/metabolismo , Integrinas/metabolismo , Mecanotransdução Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proliferação de Células , Humanos , Integrinas/química , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Moleculares , Fosfoproteínas/metabolismo , Conformação Proteica , Relação Estrutura-Atividade , Fatores de Transcrição
13.
Anticancer Res ; 39(7): 3317-3321, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262852

RESUMO

Hippo signaling is a key regulator of organ size, tissue hemostasis and regeneration. Dysregulation of the Hippo pathway has been recognized in a variety of human cancers, including pancreatic cancer. YES-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) are the two major downstream effectors of the Hippo pathway. YAP and TAZ have been found to promote pancreatic tumor development and progression, even in the absence of mutant Kirsten RAS (KRAS). Pancreatic cancer is associated with an abundant stromal reaction leading to tumor growth and immune escape. It has been found that YAP and TAZ modulate behavior of pancreatic stellate cells and recruitment of tumor-associated macrophages and myeloid-derived suppressor cells. Moreover, YAP and TAZ are associated with chemoresistance and poor prognosis in pancreatic cancer. This review dissects the role of Hippo signaling in pancreatic cancer, focusing on molecular mechanisms and prospects for future intervention.


Assuntos
Neoplasias Pancreáticas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/patologia , Fosfoproteínas/metabolismo , Transdução de Sinais , Fatores de Transcrição
14.
Gene ; 712: 143956, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31271843

RESUMO

Gastric cancer represents a common malignancy of digestive tract with high incidence and mortality. Increasing evidence suggests that the growth of gastric tumor cells relies largely on aerobic glycolysis. Currently, many potential anti-cancer candidates are derived from natural products. Here, we evaluated the effects of oleanolic acid (OA), a triterpenoid component widely found in the plants of Oleaceae family, on aerobic glycolysis and proliferation in human MKN-45 and SGC-7901 gastric cancer cells. Our results demonstrated that OA reduced the viability and proliferation of gastric cancer cells and inhibited the expression of cyclin A and cyclin-dependent kinase 2. OA blocked glycolysis in these cells evidenced by decreases in the uptake and consumption of glucose, intracellular lactate levels and extracellular acidification rate. Glycolysis inhibitor 2-deoxy-d-glucose, similar to OA, suppressed gastric cancer cell proliferation. OA also decreased the expression and intracellular activities of glycolysis rate-limiting enzymes hexokinase 2 (HK2) and phosphofructokinase 1 (PFK1). Moreover, OA downregulated the expression of hypoxia inducible factor-1α (HIF-1α) and decreased its nuclear abundance. Upregulation of HIF-1α by deferoxamine rescued OA-inhibited HK2 and PFK1. Furthermore, OA reduced the nuclear abundance of yes-associated protein (YAP) in gastric tumor cells. YAP inhibitor verteporfin, similar to OA, downregulated the expression of HIF-1α and glycolytic enzymes in gastric cancer cells; whereas overexpression of YAP abrogated all these effects of OA. Collectively, inhibition of YAP was responsible for OA blockade of HIF-1α-mediated aerobic glycolysis and proliferation in human gastric tumor cells. OA could be developed as a promising candidate for gastric cancer treatment.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ácido Oleanólico/farmacologia , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/metabolismo , Neoplasias Gástricas/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Ciclo do Ácido Cítrico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicólise , Humanos , Fosforilação , Transdução de Sinais/efeitos dos fármacos , Estômago/patologia , Neoplasias Gástricas/tratamento farmacológico , Fatores de Transcrição
15.
Nat Commun ; 10(1): 3055, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296870

RESUMO

KRAS mutations are present in over 90% of pancreatic ductal adenocarcinomas (PDAC), and drive their poor outcomes and failure to respond to targeted therapies. Here we show that Leukemia Inhibitory Factor (LIF) expression is induced specifically by oncogenic KRAS in PDAC and that LIF depletion by genetic means or by neutralizing antibodies prevents engraftment in pancreatic xenograft models. Moreover, LIF-neutralizing antibodies synergize with gemcitabine to eradicate established pancreatic tumors in a syngeneic, KrasG12D-driven, PDAC mouse model. The related cytokine IL-6 cannot substitute for LIF, suggesting that LIF mediates KRAS-driven malignancies through a non-STAT-signaling pathway. Unlike IL-6, LIF inhibits the activity of the Hippo-signaling pathway in PDACs. Depletion of YAP inhibits the function of LIF in human PDAC cells. Our data suggest a crucial role of LIF in KRAS-driven pancreatic cancer and that blockade of LIF by neutralizing antibodies represents an attractive approach to improving therapeutic outcomes.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Fator Inibidor de Leucemia/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Feminino , Técnicas de Inativação de Genes , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Fator Inibidor de Leucemia/antagonistas & inibidores , Fator Inibidor de Leucemia/genética , Camundongos , Mutação , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/genética , Fatores de Transcrição , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nat Commun ; 10(1): 3049, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296872

RESUMO

The transcription factor p63 is a master regulator of ectoderm development. Although previous studies show that p63 triggers epidermal differentiation in vitro, the roles of p63 in developing embryos remain poorly understood. Here, we use zebrafish embryos to analyze in vivo how p63 regulates gene expression during development. We generate tp63-knock-out mutants that recapitulate human phenotypes and show down-regulated epidermal gene expression. Following p63-binding dynamics, we find two distinct functions clearly separated in space and time. During early development, p63 binds enhancers associated to neural genes, limiting Sox3 binding and reducing neural gene expression. Indeed, we show that p63 and Sox3 are co-expressed in the neural plate border. On the other hand, p63 acts as a pioneer factor by binding non-accessible chromatin at epidermal enhancers, promoting their opening and epidermal gene expression in later developmental stages. Therefore, our results suggest that p63 regulates cell fate decisions during vertebrate ectoderm specification.


Assuntos
Ectoderma/embriologia , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Placa Neural/embriologia , Fosfoproteínas/metabolismo , Transativadores/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Sistemas CRISPR-Cas/genética , Diferenciação Celular/genética , Cromatina/metabolismo , Regulação para Baixo , Ectoderma/metabolismo , Embrião não Mamífero , Elementos Facilitadores Genéticos/genética , Epiderme/embriologia , Epiderme/metabolismo , Técnicas de Inativação de Genes , Modelos Animais , Placa Neural/metabolismo , Fosfoproteínas/genética , Ligação Proteica/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transativadores/genética , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética
17.
Nat Commun ; 10(1): 3005, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285450

RESUMO

How the stressosome, the epicenter of the stress response in bacteria, transmits stress signals from the environment has remained elusive. The stressosome consists of multiple copies of three proteins RsbR, RsbS and RsbT, a kinase that is important for its activation. Using cryo-electron microscopy, we determined the atomic organization of the Listeria monocytogenes stressosome at 3.38 Å resolution. RsbR and RsbS are organized in a 60-protomers truncated icosahedron. A key phosphorylation site on RsbR (T209) is partially hidden by an RsbR flexible loop, whose "open" or "closed" position could modulate stressosome activity. Interaction between three glutamic acids in the N-terminal domain of RsbR and the membrane-bound mini-protein Prli42 is essential for Listeria survival to stress. Together, our data provide the atomic model of the stressosome core and highlight a loop important for stressosome activation, paving the way towards elucidating the mechanism of signal transduction by the stressosome in bacteria.


Assuntos
Complexos Multienzimáticos/ultraestrutura , Fosfoproteínas/ultraestrutura , Proteínas Serina-Treonina Quinases/ultraestrutura , Estresse Fisiológico , Microscopia Crioeletrônica , Regulação Bacteriana da Expressão Gênica/fisiologia , Ácido Glutâmico/metabolismo , Listeria monocytogenes/fisiologia , Complexos Multienzimáticos/metabolismo , Fosfoproteínas/metabolismo , Fosforilação/fisiologia , Domínios Proteicos/fisiologia , Estrutura Secundária de Proteína , Proteínas Serina-Treonina Quinases/metabolismo , Fator sigma/metabolismo , Transdução de Sinais/fisiologia
18.
BMC Cancer ; 19(1): 654, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31269911

RESUMO

BACKGROUND: Yes-associated protein (YAP) plays a crucial role in tumour development and it is the main effector of the Hippo signalling pathway. However, the mechanism underlying YAP downregulation in laryngeal cancer is still unclear. In our previous study, we found that YAP, compared with adjacent tissues, was expressed higher in laryngeal cancer and was also closely associated with histological differentiation, TNM stage and poor prognosis. METHODS: In this study, we attempted to determine whether silenced YAP could downregulate human laryngeal carcinoma Hep-2 cells progression. YAP was downregulated in Hep-2 cells by shRNA, and the malignant ability of Hep-2 was assessed in vitro and in vivo. RESULTS: In vitro, CCK-8, colony formation and wound healing assays showed that downregulation of YAP significantly reduced the rates of proliferation, migration, and invasion in Hep-2 cells. Downregulation of YAP distinctly induced G2/M cycle arrest and increased the rate of apoptosis. Accordingly, western blot assay suggested that the expression of DKK1, vimentin and ß-catenin was significantly decreased after YAP downregulated treatment, thereby indicating that YAP mediated the EMT programme and the Wnt/ß-catenin signalling pathway in carcinoma of the larynx. Furthermore, silencing of YAP suppressed Hep-2 cell tumourigenesis and metastasis in vivo. CONCLUSION: In summary, our findings demonstrated the proliferation of YAP downregulation and the invasion of Hep-2 cells via downregulating the Wnt/ß-catenin pathway in vitro and in vivo, suggesting that YAP may provide a potential therapeutic strategy for the treatment of laryngeal cancer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patologia , Fosfoproteínas/metabolismo , beta Catenina/metabolismo , Animais , Apoptose , Movimento Celular , Proliferação de Células , Regulação para Baixo , Pontos de Checagem da Fase G2 do Ciclo Celular , Técnicas de Silenciamento de Genes , Pontos de Checagem da Fase M do Ciclo Celular , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Invasividade Neoplásica , Estadiamento de Neoplasias , RNA Interferente Pequeno , Sincalida , Fatores de Transcrição , Ensaio Tumoral de Célula-Tronco , Vimentina/metabolismo , Via de Sinalização Wnt , Cicatrização
19.
Cell Physiol Biochem ; 53(1): 200-214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31287628

RESUMO

BACKGROUND/AIMS: Skeletal mass loss is reported in several catabolic conditions and it has been associated with a reduced intracellular L-glutamine content. We investigated the association of intracellular L-glutamine concentration with the protein content in skeletal muscle cells. METHODS: We cultivated C2C12 myotubes in the absence or presence of 2 (reference condition), 8 or 16 mM L-glutamine for 48 hours, and the variations in the contents of amino acids and proteins measured. We used an inhibitor of L-glutamine synthesis (L-methionine sulfoximine - MSO) to promote a further reduction in intracellular L-glutamine levels. Amino acids contents in cells and media were measured using LC-MS/MS. We measured changes in phosphorylated Akt, RP-S6, and 4E-BP1contents in the absence or presence of insulin by western blotting. RESULTS: Reduced intracellular L-glutamine concentration was associated with decreased protein content and increased protein breakdown. Low intracellular glutamine levels were also associated with decreased p-Akt contents in the presence of insulin. A further decrease in intracellular L-glutamine caused by glutamine synthetase inhibitor reduced protein content and levels of amino acids generated from glutamine metabolism and increased bAib still further. Cells exposed to high medium glutamine levels did not have any change in protein content but exhibited increased contents of the amino acids derived from L-glutamine metabolism. CONCLUSION: Intracellular L-glutamine levels per se play a role in the control of protein content in skeletal muscle myotubes.


Assuntos
Proteínas de Transporte/metabolismo , Glutamina/metabolismo , Insulina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína S6 Ribossômica/metabolismo , Animais , Proteínas de Transporte/análise , Proteínas de Ciclo Celular , Linhagem Celular , Cromatografia Líquida , Fatores de Iniciação em Eucariotos , Glutamina/análise , Insulina/análise , Camundongos , Fibras Musculares Esqueléticas/química , Fosfoproteínas/análise , Fosforilação , Proteínas Proto-Oncogênicas c-akt/análise , Proteína S6 Ribossômica/análise , Espectrometria de Massas em Tandem
20.
Sheng Li Xue Bao ; 71(3): 405-414, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31218331

RESUMO

The present study was aimed to investigate the expression relationship of Hippo signaling molecules and ovarian germline stem cell (OGSC) markers in the development schedule of OGSCs during ovarian aging in women and mice. The ovaries of 2-month-old mature (normal control) and 12-month-old (physiological ovarian aging) KM mice were sampled, and the ovarian cortex samples of young (postpuberty to 35 years old), middle age (36-50 years old) and menopausal period (51-60 years old) women were obtained with consent. The mice model of pathological ovarian aging was established by intraperitoneal injection of cyclophosphamide/busulfan (CY/BUS). HE staining was used to detect the changes of follicles at different stages, and the localization and expression changes of Hippo signaling molecules and OGSCs related factors (MVH/OCT4) were detected by immunohistochemistry and immunofluorescence staining. Western blot was used to detect the protein expression levels of the major molecules in the Hippo signaling pathway and OGSCs related factors. The results showed that there were not any normal follicles, but a few atresia follicles in the ovaries from physiological and pathological ovarian aging mice. Compared with the normal control mice, both the physiological and pathological ovarian aging mice showed decreased protein expression levels of the main Hippo signaling molecules (pYAP1) and MVH/OCT4; Whereas only the pathological ovarian aging mice showed increased ratio of pYAP1/YAP1. In comparison with the young women, the middle age and menopausal women showed looser structure of ovarian surface epithelium (OSE) and less ovarian cortical cells. The protein expression level of LATS2 in the OSE was the highest in young women, MST1 expression was the lowest in the menopausal period women, and the expression levels of YAP1 and pYAP1 were the highest in middle age women. Compared with the young women, the middle age and menopausal period women exhibited significantly decreased ratio of OSE pYAP1/YAP1, whereas there was no significant difference between them. The expression level of MVH protein in OSE from the young women was significantly higher than those of the middle age and menopausal period women. These results indicate that there is an expression relationship between the main molecules of Hippo signaling pathway and OGSCs related factors, which suggests that Hippo signaling pathway may regulate the expression levels of OGSCs related factors, thus participating in the process of physiological and pathological degeneration of ovarian.


Assuntos
Envelhecimento , Células-Tronco de Oogônios/metabolismo , Ovário , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adulto , Animais , Epitélio , Feminino , Humanos , Camundongos , Pessoa de Meia-Idade , Fator 3 de Transcrição de Octâmero/metabolismo , Folículo Ovariano , Fosfoproteínas/metabolismo , Transdução de Sinais , Fatores de Transcrição , Proteínas Supressoras de Tumor/metabolismo
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