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1.
Mol Cancer ; 19(1): 20, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005118

RESUMO

BACKGROUND: Accumulating evidence indicates that circular RNAs (circRNAs) act as microRNA (miRNA) sponges to directly inhibit specific miRNAs and alter their ability to regulate gene expression at the post-transcriptional level; this mechanism is believed to occur in various cancers. However, the expression level, precise function and mechanism of circ_001680 in colorectal carcinoma (CRC) are largely unknown. METHODS: qRT-PCR was used to detect the expression of circ_001680 and miR-340 in human CRC tissues and their matched normal tissues. Bioinformatics analyses and dual-fluorescence reporter assays were used to evaluate whether circ_001680 could bind to miR-340. Circ_001680 overexpression and knockdown cell lines were constructed to investigate the proliferation and migration abilities in vivo and in vitro through function-based experiments, including CCK8, plate clone formation, transwell, and wounding healing assays. The relationships among circ_001680, miR-340 and BMI1 were investigated by bioinformatics analyses, dual-fluorescence reporter system, FISH, RIP and RNA pull down assays. Sphere forming assays and flow cytometry analyses were used to assess the effect of circ_001680 on the stemness characteristics of CRC cells. RESULTS: Circ_001680 was more highly expressed in of CRC tissue than in matched adjacent normal tissues from the same patients. Circ_001680 was observed to enhance the proliferation and migration capacity of CRC cells. Furthermore, dual-fluorescence reporter assays confirmed that circ_001680 affects the expression of BMI1 by targeting miR-340. More importantly, we also found that circ_001680 could promote the cancer stem cell (CSC) population in CRC and induce irinotecan therapeutic resistance by regulating the miR-340 target gene BMI1. CONCLUSIONS: Our results demonstrated that circ_001680 is a part of a novel strategy to induce chemotherapy resistance in CRC through BMI1 upregulation. Moreover, circ_001680 may be a promising diagnostic and prognostic marker to determine the success of irinotecan-based chemotherapy.

2.
Biochem Biophys Res Commun ; 522(3): 757-762, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31791578

RESUMO

Loss of E-cadherin elicits epithelial-mesenchymal transition (EMT). While both the Src family of membrane-associated non-receptor tyrosine kinases (SFKs) and Slit2 binding to Roundabout 1 (Robo1) have been shown to induce E-cadherin repression and EMT, whether these two signaling pathways are mechanistically coupled remains unknown in epithelial cells. Here we found that Slit2 and Robo1 overexpression activated Src kinases for tyrosine phosphorylation, degradation of E-cadherin and induction of EMT. Specific blockade of Slit2 binding to Robo1 inactivated Src, prevented E-cadherin phosphorylation and EMT induction. Biochemically, the cytoplasmic CC3 motif of Robo1 (CC3) bound directly to the SH2 and 3 domains of c-Src and the cytoplasmic domains of E-cadherin. Slit2 induced Robo1 association with endogenous c-Src and E-cadherin, whereas ectopic expression of CC3 dissociated this protein complex in colorectal epithelial cells. These results indicate that Slit2 not only induces Robo1 binding to Src, but also recruits Src to E-cadherin for tyrosine phosphorylation of E-cadherin, leading to E-cadherin degradation and EMT induction in colorectal epithelial cells.

3.
Ecotoxicol Environ Saf ; 189: 110037, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31812018

RESUMO

As an emerging class of nitrogenous disinfection by-products (N-DBPs), haloacetamides (HAcAms) have been widely detected in drinking water. Limited toxicity studies have shown an inconsistent toxicity of monoHAcAms, including CAcAm, BAcAm and IAcAm. In this study, the developmental toxicity of monoHAcAms was evaluated in embryo-larval stage of zebrafish. Embryos were exposed to one concentration of 2.50, 5.00, 10.0, 20.0, 40.0 and 80.0 mg/L monoHAcAms from 4 h post-fertilization (hpf) to 120 hpf. Multiple endpoints, including hatching rate, morphological abnormalities, mortality as well as locomotor behavior were assessed at specified stages (24, 48, 72, 96 and 120 hpf). Results showed that 80 mg/L CAcAm and 40 mg/L BAcAm significantly decreased the hatching rate, IAcAm decreased the hatching rate and delayed the hatching process in a concentration-dependent manner with an EC50 of 16.37 mg/L at 72 hpf. The frequency and severity order of morphological abnormalities increased with the raised exposure concentrations and prolonged exposure time, and the corresponding EC50 at 96 hpf were 21.10, 9.77 and 16.60 mg/L for CAcAm, BAcAm and IAcAm, respectively. MonoHAcAms exposure resulted in a time- and dose-dependent response in mortality and the calculated LC50 at 72 hpf were 38.44, 17.74 and 28.82 mg/L for CAcAm, BAcAm and IAcAm, respectively. Based on EC50 for morphological abnormalities and LC50, a toxicity rank order of BAcAm > IAcAm > CAcAm was observed. Different degrees of hyperactivity and hypoactivity were observed from locomotor behavior analysis in larvae from ≤10.0 mg/L monoHAcAms exposure groups. The light-dark periodic change was disappeared in larvae of 10.0 mg/L BAcAm exposure group. In summary, our study showed that monoHAcAms were developmentally toxic to zebrafish even at very low concentrations and BAcAm exerted higher toxicity than IAcAm and CAcAm. These results will further our understanding of the toxicity of HAcAms and its potential toxicological impact on human and ecological environment.

4.
Braz J Med Biol Res ; 52(12): e8735, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826179

RESUMO

Exosomes, a kind of extracellular vesicle, are promising therapeutic agents for spinal cord injury (SCI). This article aimed to investigate effects of exosomes secreted from miRNA-29b-modified bone marrow mesenchymal stem cells (BMSCs) on SCI. Exosomes were extracted from BMSCs transfected with miRNA-29b or negative control (miR NC). SCI rats were injected intravenously with exosomes (control exosomes, miRNA-29b exosomes) and BMSCs (miR NC, miRNA-29b) through the tail vein. The expression of miRNA-29b in spinal cord tissues of SCI rats was detected by qRT-PCR. The hind limb motor function was evaluated by Basso Beattie Bresnahan (BBB) score. The histopathological damage and neuronal regeneration in spinal cord tissues was observed by HE staining and immunohistochemistry, respectively. The injection of miRNA-29b exosomes and miRNA-29b BMSCs both significantly increased the expression of miRNA-29b in spinal cord tissues of SCI rats (P<0.05). Compared with SCI rats, rats in the miRNA-29b exosomes and the miRNA-29b groups exhibited improved SCI, including increased BBB score, NF200 and GAP-43 positive neurons, as well as decreased contractile nerve cell numbers and GFAP positive neurons (all P<0.05). The relieving degree of SCI was significantly higher in the miRNA-29b exosomes group than in the miRNA-29b BMSCs group (P<0.05). Exosomes secreted from miRNA-29b-modified BMSCs were effective in the repair of SCI in rats.


Assuntos
Exossomos/metabolismo , Transplante de Células-Tronco Mesenquimais , MicroRNAs/metabolismo , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/terapia , Transfecção , Animais , Modelos Animais de Doenças , Feminino , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Sci Total Environ ; 692: 1267-1275, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539958

RESUMO

Humans are exposed to disinfection by-products (DBPs) mainly through drinking water ingestion and dermal contact. As an emerging class of nitrogenous DBPs (N-DBPs), haloacetamides (HAcAms) have been found to have significantly higher cytotoxicity than regulated DBPs. In this study, we investigated the cytotoxicity of HAcAms on two exposure pathway-related cell lines: human gastric epithelial GES-1 cells and immortalized keratinocytes HaCaT. Our results showed that the ranking order of cytotoxicity of 13 HAcAms was different between HaCaT and GES-1 cells. In addition, the 50% inhibitive concentration in HaCaT was 1.01-3.29 times that in GES-1. Further comparison among GES-1, HaCaT and CHO cell lines confirmed that different cell lines exhibited different sensitivity to the same compound. Importantly, HAcAms showed 5.83-7.13 × 104 times higher toxicity than the well-clarified DBP chloroform, clearly demonstrating the increased toxicity of HAcAms. Finally, using a novel high-content screening (HCS) analysis, we found that 39.29% of chlorinated HAcAms, 42.86% of brominated HAcAms and 16.07% of iodinated HAcAms significantly affected at least one of the cell-health parameters, such as nuclear size, membrane permeability, mitochondrial membrane potential, or cytochrome c release, in GES-1 or HaCaT cells. Thus, brominated HAcAms appear to have stronger effects under the sublethal exposure dose, possibly causing cytotoxicity via apoptosis. Together, our study provides new insights to the toxicity of HAcAms and a comprehensive toxicology dataset for health risk assessment.


Assuntos
Acetamidas/toxicidade , Desinfetantes/toxicidade , Poluentes Químicos da Água/toxicidade , Linhagem Celular , Desinfecção , Humanos , Testes de Toxicidade
6.
Cell ; 178(6): 1478-1492.e20, 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31474362

RESUMO

Liver fibrosis is a very common condition seen in millions of patients with various liver diseases, and yet no effective treatments are available owing to poorly characterized molecular pathogenesis. Here, we show that leukocyte cell-derived chemotaxin 2 (LECT2) is a functional ligand of Tie1, a poorly characterized endothelial cell (EC)-specific orphan receptor. Upon binding to Tie1, LECT2 interrupts Tie1/Tie2 heterodimerization, facilitates Tie2/Tie2 homodimerization, activates PPAR signaling, and inhibits the migration and tube formations of EC. In vivo studies showed that LECT2 overexpression inhibits portal angiogenesis, promotes sinusoid capillarization, and worsens fibrosis, whereas these changes were reversed in Lect2-KO mice. Adeno-associated viral vector serotype 9 (AAV9)-LECT2 small hairpin RNA (shRNA) treatment significantly attenuates fibrosis. Upregulation of LECT2 is associated with advanced human liver fibrosis staging. We concluded that targeting LECT2/Tie1 signaling may represent a potential therapeutic target for liver fibrosis, and serum LECT2 level may be a potential biomarker for the screening and diagnosis of liver fibrosis.

7.
Inflammopharmacology ; 27(4): 845-856, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165333

RESUMO

Previously, ginsenoside metabolite compound K (C-K) was able to reduce B cell proliferation and serum anti-type II collagen (anti-CII) antibody to normal levels in mice with collagen-induced arthritis (CIA); however, the mechanism by which C-K restores B cell balance is unclear. In the present work, C-K treatment not only alleviated the polyarthritis index, swollen joint count, pathological scores of spleen and joints, spleen index, B cell proliferation and the level of serum antibodies (IgG1, IgG2a and anti-collagen II), but C-K treatment also restored B cell subsets including regulatory B cells, plasma cells, memory B cells, mature B cells, and follicular B cells in CIA mice. Interestingly, C-K did not change the expression level of immunoglobulin D-type B-cell receptor (IgD-BCR) but promoted IgD-BCR endocytosis. C-K treatment enhanced ß-arrestin1 expression, facilitating the colocalization between IgD and ß-arrestin1, as well as colocalization between IgD and adaptor protein 2 (AP2). Inhibition of the ß-arrestin1-AP2 interaction with barbadin significantly reduced the ability of C-K to attenuate IgD-BCR plasma membrane localization. These results taken together depict that C-K ameliorates CIA in part by inhibiting B cell activation through the triggering of IgD-BCR internalization in a ß-arrestin1-AP2 dependent manner.


Assuntos
Artrite Experimental/tratamento farmacológico , Linfócitos B/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Ginsenosídeos/farmacologia , Imunoglobulina D/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Complexo 2 de Proteínas Adaptadoras/metabolismo , Animais , Artrite Experimental/induzido quimicamente , Artrite Experimental/metabolismo , Linfócitos B/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Colágeno/farmacologia , Imunoglobulina G/metabolismo , Articulações/efeitos dos fármacos , Articulações/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Masculino , Camundongos , Baço/efeitos dos fármacos , Baço/metabolismo , beta-Arrestina 1/metabolismo
8.
Biomed Pharmacother ; 115: 108909, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31071508

RESUMO

Ginsenoside metabolite compound-K (C-K), which is an active metabolite of ginsenoside in vivo, can produce anti-inflammatory affects by activating glucocorticoid receptors (GRs) to inhibit the expression of ß-arrestin2. Studies have shown that C-K can inhibit the function of immune cells including macrophage polarization and phagocytosis. However, the mechanism by which C-K regulates macrophage polarization is currently unclear. Toll-like receptors (TLRs) are the pattern recognition receptors on the membrane of immune cells, with TLR4 being especially important in polarization of macrophages. The Gαi-mediated activation of nuclear factor-κB (NF-κB) by TLR4 promotes inflammation and phagocytosis in macrophages by increasing the proportion of type I phenotypic macrophages (M1). Whether C-K inhibits the signal transduction of TLR4-Gαi-NF-κB and how that effects macrophage polarization regulation in murine models of RA is not reported. The coupling of G proteins with receptors is regulated by ß-arrestin2, but it has been unclear whether C-K modulates the TLR4 interaction with G proteins by inhibiting the expression of ß-arrestin2. To explore these questions, the collagen-induced arthritis (CIA) mouse model was employed, and mice were treated with C-K (112 mg/kg/day). The results depict that C-K treatment inhibits macrophage phagocytosis and reduces the proportion of M1. C-K decreases the overexpressed ß-arrestin2, Gαi, TLR4 and NF-κB in macrophages of CIA mice, while increasing the expression of Gαs. Furthermore, C-K promotes TLR4-Gαs coupling and inhibits TLR4-Gαi coupling through ß-arrestin2 regulation in macrophages, leading to a decrease in the proportion of M1 to M2 macrophages and improved outcomes in CIA mice.


Assuntos
Artrite Experimental/tratamento farmacológico , Ginsenosídeos/uso terapêutico , Macrófagos Peritoneais/efeitos dos fármacos , beta-Arrestina 2/antagonistas & inibidores , Animais , Artrite Experimental/imunologia , Artrite Experimental/patologia , Células Cultivadas , Citocinas/sangue , Articulações do Pé/efeitos dos fármacos , Articulações do Pé/imunologia , Articulações do Pé/patologia , Macrófagos Peritoneais/imunologia , Camundongos Endogâmicos DBA , Fagocitose/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/imunologia , Timo/efeitos dos fármacos , Timo/imunologia , beta-Arrestina 2/genética
9.
Biomed Pharmacother ; 114: 108796, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30921706

RESUMO

B-cell activating factor from the tumor necrosis factor family (BAFF) has revealed its critical role in B cell proliferation and survival, as well as the pathogenesis of T-cell mediated autoimmune disease. However, the effect and molecular mechanisms of BAFF on T cell physiological function have not been fully elucidated. In this study it was seen that BAFF can promote the vitality of purified T cells, increase the proportion of CD3+CD4+, CD4+CD25+, CD4+CD154+, and CD4+CD69+ subgroups and reduce the proportion of CD4+CD62L+ subgroups. Negating BAFF activity with Atacicept (TACI-Fc) reverses vitality and activation of T cells. Furthermore, immunofluorescence detection revealed that BAFF promotes the expression of BAFF receptor (BAFF-R) and transmembrane activator and CAML interactor (TACI) in T cells. Flow cytometry displayed that BAFF/BAFF-R activates the PI3K-Akt signaling pathway while the application of PI3K inhibitor (wortmannin) illuminated that BAFF induces T cell vitality and activation through the PI3K-Akt signaling pathway. We conclude that BAFF is involved in not only the physiology of B cells, but also that of T cells. BAFF affects physiological T-cell activation through BAFF-R-mediated activation of the PI3K-Akt signaling pathway which mirrors one of the pathological mechanisms of T cell-mediated autoimmune diseases.


Assuntos
Fator Ativador de Células B/imunologia , Ativação Linfocitária/imunologia , Fosfatidilinositol 3-Quinases/imunologia , Proteínas Proto-Oncogênicas c-akt/imunologia , Transdução de Sinais/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD/imunologia , Receptor do Fator Ativador de Células B/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL
10.
Carbohydr Polym ; 210: 119-126, 2019 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-30732744

RESUMO

Here we propose a wet-spinning assembly approach to continuously spin nanoTiO2/chitosan (CS) nanocomposite fibers, which are used directly as absorbents to remove free fatty acids (FFA) from edible oils. The morphology of nanoTiO2 and nanoTiO2/CS nanocomposite fibers was observed by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The structure of the fibers was studied by Fourier transform infrared spectroscopy (FTIR), and wide angel X-ray diffractometry (WAXD). Moreover, the mechanical property, thermal stability, and antibacterial activity of the fibers were evaluated. These fibers were used for the deacidification of rice bran oil and the acid value of the oil was found decreased from 4.53 ± 0.15 to 1.07 ± 0.06 mg KOH/g within 5 h with a 10 wt % load at 50 ℃. The combination of wet-spinning technology and excellent performance of nanoTiO2/CS nanocomposite fibers paves the way to eco-friendly and sustainable material for FFA removal.

11.
Nat Commun ; 10(1): 663, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30737378

RESUMO

The biological role of miR-500a-5p has not yet been reported in the context of colorectal cancer (CRC). Here, we show that miR-500a-5p expression is decreased in CRC tissues compared with adjacent normal tissues. Low miR-500a-5p expression is associated with malignant progression. Moreover, transfection of CRC cells with miR-500a-5p induces G0/G1 cell cycle arrest and inhibits their growth and migration. Mechanistically, miR-500a-5p directly targets HDAC2 and inhibits HDAC2-mediated proliferation in CRC in nude mice. Furthermore, YY1 binds to the promoter of miR-500a-5p and negatively regulates its transcription. Restoration of miR-500a-5p expression is up-regulated via the p300/YY1/HDAC2 complex. Besides, therapeutic delivery of miR-500a-5p significantly suppresses tumour development in a xenograft tumour model and a HDAC2 inhibitor FK228-treated CRC model. Our studies demonstrate that miR-500a-5p functions as a tumour suppressor in CRC by targeting the p300/YY1/HDAC2 axis, which contributes to the development of and provides new potential candidates for CRC therapy.


Assuntos
Neoplasias Colorretais/metabolismo , Proteína p300 Associada a E1A/metabolismo , Histona Desacetilase 2/metabolismo , MicroRNAs/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Apoptose/genética , Apoptose/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Neoplasias Colorretais/genética , Proteína p300 Associada a E1A/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Células HCT116 , Histona Desacetilase 2/genética , Humanos , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fator de Transcrição YY1/genética
12.
J Cell Physiol ; 2019 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30710358

RESUMO

Phosphoinositide 3-kinase (PI3K), a crucial signaling molecule, is regulated by various upstream regulators. Traditionally, receptor tyrosine kinases and G protein-coupled receptor are regarded as its principle upstream regulators; however, recent reports have indicated that spleen tyrosine kinase, ß-arrestin2, Janus kinase, and RAS can also perform this role. Dysregulation of PI3K is common in the progression of various diseases, including, but not limited to, tumors, Alzheimer's disease, Parkinson's disease, rheumatoid arthritis, and acute myelogenous leukemia. The aim of this review is to provide a perspective on PI3K-related diseases examining both the classical and nonclassical upstream regulators of PI3K in detail.

13.
BMC Struct Biol ; 19(1): 1, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30646888

RESUMO

BACKGROUND: Ribose-phosphate pyrophosphokinase (EC 2.7.6.1) is an enzyme that catalyzes the ATP-dependent conversion of ribose-5-phosphate to phosphoribosyl pyrophosphate. The reaction product is a key precursor for the biosynthesis of purine and pyrimidine nucleotides. RESULTS: We report the 2.2 Å crystal structure of the E. coli ribose-phosphate pyrophosphobinase (EcKPRS). The protein has two type I phosphoribosyltransferase folds, related by 2-fold pseudosymmetry. The propeller-shaped homohexameric structure of KPRS is composed of a trimer of dimers, with the C-terminal domains forming the dimeric blades of the propeller and the N-terminal domains forming the hexameric core. The key, conserved active site residues are well-defined in the structure and positioned appropriately to bind substrates, adenosine monophosphate and ribose-5-phosphate. The allosteric site is also relatively well conserved but, in the EcKPRS structure, several residues from a flexible loop occupy the site where the allosteric modulator, adenosine diphosphate, is predicted to bind. The presence of the loop in the allosteric site may be an additional level of regulation, whereby low affinity molecules are precluded from binding. CONCLUSIONS: Overall, this study details key structural features of an enzyme that catalyzes a critical step in nucleotide metabolism. This work provides a framework for future studies of this important protein and, as nucleotides are critical for viability, may serve as a foundation for the development of novel anti-bacterial drugs.


Assuntos
Escherichia coli/enzimologia , Ribose-Fosfato Pirofosfoquinase/química , Ribose-Fosfato Pirofosfoquinase/metabolismo , Difosfato de Adenosina/farmacologia , Sítio Alostérico , Cristalografia por Raios X , Escherichia coli/química , Proteínas de Escherichia coli/química , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Multimerização Proteica
14.
ACS Infect Dis ; 5(2): 250-259, 2019 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-30485744

RESUMO

The suppressor of T-cell receptor signaling (Sts) proteins, Sts-1, has recently emerged as a potential immunostimulatory target for drug development. Genetic inactivation of the Sts proteins dramatically increases host survival of systemic infection and leads to improved pathogen clearance. The protein tyrosine phosphatase (PTP) activity of these proteins arises from a C-terminal 2-histidine phosphatase (HP) domain. To identify new inhibitors of the HP activity of Sts-1, we miniaturized a phosphatase assay to a 1536-well format and conducted a 20 580 compound screen. Among the hits were two classes of structurally related compounds, tetracycline variants and sulfonated azo dyes. These hits had low micromolar to nanomolar IC50 values. Orthogonal screening confirmed the validity of these inhibitors and demonstrated that both act competitively on Sts-1 phosphatase activity. When tested on other PTPs, PTP1B and SHP1, it was found that the tetracycline PTP1B, SHP1, the tetracycline variant (doxycycline), and the sulfonated azo dye (Congo red) are selective inhibitors of Sts-1HP, with selectivity indices ranging from 19 to as high as 200. The planar polyaromatic moieties present in both classes of compounds suggested a common binding mode. The mutation of either tryptophan 494 or tyrosine 596, located near the active site of the protein, reduced the Ki of the inhibitors from 3- to 18-fold, indicating that these residues may help to promote the binding of substrates with aromatic groups. This work provides new insights into substrate selectivity mechanisms and describes two classes of compounds that can serve as probes of function or as a basis for future drug discovery.


Assuntos
Modelos Moleculares , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Domínio Catalítico , Descoberta de Drogas , Ensaios de Triagem em Larga Escala , Concentração Inibidora 50 , Cinética , Camundongos , Bibliotecas de Moléculas Pequenas
15.
J Clin Lab Anal ; 33(3): e22708, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30390349

RESUMO

BACKGROUND: Human papillomavirus (HPV) infection can lead to the development of cervical cancer. This study assessed the genotype distribution of HPV of high-grade squamous intraepithelial lesion (HSIL) and invasive cervical cancer (ICC) in Ganzhou population. METHODS: A total of 935 females who got HPV testing from January 2016 to July 2018 in the maternal and child health hospital of Ganzhou were enrolled in the study, including 806 HSIL and 129 ICC. HPV detection and genotyping were tested by HPV Geno-Array test kit. RESULTS: The overall HPV-positive rate was 74.0% in Ganzhou. Among the HSIL and ICC patients, the positive rates of HPV detection were 75.6% and 64.3%. Among the HSIL individuals, the most prevalent hr-HPV genotype was HPV 16. And the 4 common subtypes in decreasing order were HPV 52, 58, 33, and 18. Of the ICC patients, the most frequently hr-HPV subtype was HPV 16 followed by 18, 52, 58, and 59. Among the squamous cell carcinoma (SCC) patients, for hr-HPV genotypes, HPV 16, 18, 52, 58, and 59 were five most common subtypes. In patients with adenocarcinoma (ADC), the most common hr-HPV genotype was HPV 18, followed by HPV 16, 52, 56, 68, 73. And, we found U-shaped and S-shaped curves in the HPV distribution of different age groups. CONCLUSION: The prevalence and distribution of HPV genotypes in Ganzhou differed from other regions of China and Western countries. These results can serve as valuable reference for HPV vaccination programs for Ganzhou women.


Assuntos
Papillomaviridae/genética , Infecções por Papillomavirus , Lesões Intraepiteliais Escamosas Cervicais , Neoplasias do Colo do Útero , Adulto , China/epidemiologia , Estudos Transversais , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Prevalência , Lesões Intraepiteliais Escamosas Cervicais/epidemiologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/virologia , Adulto Jovem
16.
Theranostics ; 8(20): 5744-5757, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30555578

RESUMO

Rationale: This study is to validate the clinicopathologic significance and potential prognostic value of SLP2 in gastric cancer (GC), to investigate the biological function and regulation mechanism of SLP2, and to explore potential therapeutic strategies for GC. Methods: The expression of SLP2 in GC tissues from two cohorts was examined by IHC. The biological function and regulation mechanism of SLP2 and PHB was validated via loss-of-function or gain-of-function experiments. In vitro proliferation detection was used to evaluate the therapeutic effects of Sorafenib. Results: We validated that SLP2 was significantly elevated in GC tissues and its elevation was associated with poor prognosis of patients. Loss of SLP2 drastically suppressed the proliferation of GC cells and inhibited the tumor growth, while SLP2 overexpression promoted the progression of GC. Mechanistically, SLP2 competed against E3 ubiquitin ligase SKP2 to bind with PHB and stabilized its expression. Loss of SLP2 significantly suppressed phosphorylation of Raf1, MEK1/2, ERK1/2 and ELK1. Furthermore, phosphorylated ELK1 could in turn activate transcription of SLP2. Finally, we demonstrated that a Raf1 inhibitor, Sorafenib, was sufficient to inhibit the proliferation of GC cells. Conclusion: Our findings demonstrated a positive feedback loop of SLP2 which leads to acceleration of tumor progression and poor survival of GC patients. This finding also provided evidence for the reason of SLP2 elevation. Moreover, we found that sorafenib might be a potential therapeutic drug for GC and disrupting the interaction between SLP2 and PHB might also serve as a potential therapeutic target in GC.


Assuntos
Proteínas Sanguíneas/metabolismo , Retroalimentação Fisiológica , Proteínas de Membrana/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Neoplasias Gástricas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular , Proliferação de Células , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Adulto Jovem
17.
Front Pharmacol ; 9: 1313, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30538630

RESUMO

Disorder of the sympathetic nervous system (SNS) is closely related to the pathogenesis of various autoimmune diseases (ADs). Catecholamine triggered beta2-adrenergic receptor (ß2-AR) signaling is important in creating a bidirectional response in the progression of ADs due to factors including diverse expression patterns, single nucleotide polymorphisms (SNPs), biased signals, and desensitization of ß2-AR, as well as different subtypes of Gα binding to ß2-AR. In this review, we summarize the actions of ß2-AR signaling in regulating the functions of immunocytes and in the pathogenesis of ADs, and the application of ß2-AR agonists or antagonists in treating major types of ADs is also discussed. We suggest that restoring the immune balance via a soft regulation of the expression or activation of ß2-AR is one of the promising therapeutic strategies for systematic ADs.

18.
Inorg Chem ; 57(23): 14872-14881, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30427192

RESUMO

In this work, the morphology, composition, crystal, and electronic structure of Ca8Mg(SiO4)4Cl2 (CMSOC) prepared by a high-temperature solid-state reaction technique are characterized first. To investigate the site occupancies of Eu3+ and Ce3+ in CMSOC, the emission spectra under well-chosen wavelength excitations and the corresponding excitation spectra by monitoring of the specific wavelength emissions are measured in detail for singly doped samples with different concentrations. Two kinds of Eu3+ or Ce3+ luminescence spectra are found. On the basis of the chemical environments of two Ca2+ sites and dielectric chemical bond theory, the sites of these two kinds of Eu3+ and Ce3+ luminescence spectra are respectively assigned. Because energy transfer between the two types of luminescent centers, concentration-dependent emission-wavelength shifting, and luminescence concentration quenching are negligible, the emission spectra of Eu3+ and Ce3+ give us a hint of their occupation preferences on two Ca2+ sites. The results indicate that, with an increase of the doping concentration, the Eu3+ ions with smaller cationic size show an occupation preference on the smaller Ca2+(1) sites, but the Ce3+ ions with larger cationic size are inclined to enter the larger Ca2+(2) sites. These opposite occupation preferences of Eu3+ and Ce3+ in CMSOC are thought to be the cationic-size-driven site selection.


Assuntos
Cério/análise , Európio/análise , Luminescência , Substâncias Luminescentes/química , Cálcio/química , Cloretos/química , Transferência de Energia , Íons/análise , Substâncias Luminescentes/síntese química , Medições Luminescentes , Magnésio/química , Tamanho da Partícula , Silicatos/química , Propriedades de Superfície
19.
Thromb Res ; 172: 128-134, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30412834

RESUMO

BACKGROUND: Congenital hypofibrinogenemia is a type of hereditary disease characterized by impaired fibrinogen synthesis and/or secretion induced by mutations in the fibrinogen gene. OBJECTIVES: We investigated the phenotypes, genotypes, and pathogenesis of congenital hypofibrinogenemia in an affected family. PATIENTS/METHODS: The proband had a risk of bleeding; therefore, conventional coagulation screening was performed for the proband and her family members. Mutation sites in all exons and flanking sequences of FGA, FGB, and FGG were identified, with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry (MS) performed to indicate the expression of abnormal chains. The effect of the mutation sites on fibrinogen structure and function was predicted by molecular modeling, and purified plasma fibrinogen from the proband was analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and scanning electron microscopy. Thromboelastography was applied to assess the risk of bleeding and clotting in the proband. RESULTS: Fibrinogen levels in the proband were 1.21 g/L, 1.31 g/L, and 1.38 g/L according to Clauss assay, the prothrombin time method, and enzyme-linked immunosorbent assay, respectively. A novel heterozygous mutation (γCys165Arg), a heterozygous mutation (AαIle6Val), and two genetic polymorphisms (AαThr331Ala and BßArg478Lys) in fibrinogen were found in the proband, and MALDI-TOF MS indicated absence of the mutated chain in patient plasma. Additionally, the heterozygous mutation (γCys165Arg) displayed substitution of a nonpolar γ165Cys (low mass) with a positively charged Arg (high mass) along with a small fiber diameter and loose network structure. CONCLUSIONS: Fibrinogen γCys165Arg mutations cause damage to the interchain disulfide bonds of fibrinogen and hinder fibrinogen secretion, possibly explaining the pathological mechanism associated with congenital hypofibrinogenemia.


Assuntos
Afibrinogenemia/genética , Fibrinogênio/genética , Mutação Puntual , Polimorfismo Genético , Adulto , Afibrinogenemia/sangue , Sequência de Aminoácidos , Coagulação Sanguínea , Feminino , Fibrinogênio/análise , Fibrinogênio/ultraestrutura , Heterozigoto , Humanos , Masculino , Modelos Moleculares , Linhagem , Alinhamento de Sequência
20.
J Exp Clin Cancer Res ; 37(1): 238, 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30253791

RESUMO

BACKGROUND: Aberrant activation of Wnt/ß-catenin signaling pathway is considered to be an important issue in progression and metastasis of various human cancers, especially in colorectal cancer (CRC). MiR-452 could activate of Wnt/ß-catenin signaling. But the mechanism remains unclear. METHODS: The expression of miR-452 in CRC and normal tissues was detected by real-time quantitative PCR. The effect of miR-452 on CRC growth and invasion was conducted by functional experiments in vitro and in vivo. Bioinformatics and cell luciferase function studies verified the direct regulation of miR-452 on the 3'-UTR of the GSK3ß, which leads to the activation of Wnt/ß-catenin signaling. RESULTS: MiR-452 was upregulated in CRC compared with normal tissues and was correlated with clinical significance. The luciferase reporter system studies affirmed the direct regulation of miR-452 on the 3'-UTR of the GSK3ß, which activate the Wnt/ß-catenin signaling. The ectopic upregulation of miR-452 significantly inhibited the expression of GSK3ß and enhanced CRC proliferation and invasion in vitro and in vivo. Meanwhile, knockdown of miR-452 significantly recovered the expression of GSK3ß and attenuated Wnt/ß-catenin-mediated cell metastasis and proliferation. More important, T-cell factor/lymphoid enhancer factor (TCF/LEF) family of transcription factors, which are crucial downstream molecules of the Wnt/ß-catenin signaling pathway was verified as a valid transcription factor of miR-452's promoter. CONCLUSIONS: Our findings first demonstrate that miR-452-GSK3ß-LEF1/TCF4 positive feedback loop induce CRC proliferation and migration.


Assuntos
Proliferação de Células/genética , Neoplasias Colorretais/genética , Glicogênio Sintase Quinase 3 beta/genética , MicroRNAs/genética , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Masculino , Camundongos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Regiões Promotoras Genéticas , Fator de Transcrição 4/genética , Via de Sinalização Wnt/genética , Ensaios Antitumorais Modelo de Xenoenxerto
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