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1.
Mol Cell ; 82(13): 2443-2457.e7, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35613620

RESUMO

RAF protein kinases are effectors of the GTP-bound form of small guanosine triphosphatase RAS and function by phosphorylating MEK. We showed here that the expression of ARAF activated RAS in a kinase-independent manner. Binding of ARAF to RAS displaced the GTPase-activating protein NF1 and antagonized NF1-mediated inhibition of RAS. This reduced ERK-dependent inhibition of RAS and increased RAS-GTP. By this mechanism, ARAF regulated the duration and consequences of RTK-induced RAS activation and supported the RAS output of RTK-dependent tumor cells. In human lung cancers with EGFR mutation, amplification of ARAF was associated with acquired resistance to EGFR inhibitors, which was overcome by combining EGFR inhibitors with an inhibitor of the protein tyrosine phosphatase SHP2 to enhance inhibition of nucleotide exchange and RAS activation.


Assuntos
Neurofibromina 1 , Proteínas Proto-Oncogênicas A-raf , Proteínas Ativadoras de ras GTPase , Receptores ErbB/genética , Receptores ErbB/metabolismo , Guanosina Trifosfato/metabolismo , Humanos , Neurofibromina 1/metabolismo , Ligação Proteica , Proteínas Proto-Oncogênicas A-raf/metabolismo , Transdução de Sinais , Proteínas Ativadoras de ras GTPase/metabolismo
2.
Int J Mol Sci ; 25(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38542168

RESUMO

Crocin is a unique water-soluble carotenoid found in crocus and gardenia flowers. Crocin has been shown to have a variety of pharmacological activities, such as antioxidant, anti-cancer, memory improvement, antidepressant, anti-ischemia, blood pressure lowering and aphrodisiac, gene protection and detoxification activities. Due to their amphiphilicity, crocin molecules form concentration-dependent self-associates (micelles) in a water solution. In the present study, using various NMR techniques (T2 relaxation and selective gradient NOESY), we have demonstrated that crocin forms mixed micelles with water-soluble drug delivery system glycyrrhizin and linoleic acid molecules. Note, that the spin-spin T2 relaxation time and NOESY spectroscopy are very sensitive to intermolecular interactions and molecular diffusion mobility. The second purpose of this work was the elucidation of the interaction of crocin with a model lipid membrane using NMR techniques and a molecular dynamics simulation and its effects on lipid oxidation. It was shown that the crocin molecule is located near the surface of the lipid bilayer and effectively protects lipids from oxidation by peroxyl radicals. The role of glycyrrhizin and vitamin C in metal-induced lipid oxidation was also elucidated. The results of this study may be useful for expanding the field of application of crocin in medicine and in the food industry.


Assuntos
Antioxidantes , Crocus , Antioxidantes/farmacologia , Antioxidantes/química , Micelas , Água , Ácido Glicirrízico/farmacologia , Carotenoides/farmacologia , Carotenoides/química , Lipídeos , Crocus/química
3.
Oral Dis ; 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183989

RESUMO

OBJECTIVE: Oral squamous cell carcinoma (OSCC) is the most common malignant tumour in the oral cavity. OSCC is aggressive and prone to metastasis; it is associated with high mortality and short survival. In this study, we investigated the function of the long non-coding RNA LINC00525 in OSCC progression and the molecular mechanisms through in vitro and in vivo experiments. MATERIALS AND METHODS: CCK8 assay was used to detect the effect of LINC00525 on cell viability; transwell migration and invasion assays and scratch assay were used to examine the role of LINC00525 in cell migration and invasion. Flow cytometry, RT-PCR and western blot were used to detect apoptosis indexes. Tumorigenic effects were investigated using mouse xenograft tumour models. RESULTS: LINC00525 was associated with OSCC survival and prognosis. LINC00525 knockdown decreased cell viability and epithelial-mesenchymal transition (EMT) properties and increased apoptosis and also shortened the cell cycle of OSCC cells in vitro. The downregulation of LINC00525 reduced the growth of OSCC tumour in vivo. LINC00525 can regulate OSCC cells via the apoptotic signalling pathway. CONCLUSION: Our results indicate that LINC00525 exhibits oncogenic functions in OSCC. LINC00525 may be a new promising and potential target for the treatment of OSCC.

4.
Biochem Genet ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38017285

RESUMO

Endometriosis (EMT) is a prevalent gynecological disorder characterized by pain and infertility associated with the menstrual cycle. Pyroptosis, an emerging cell death mechanism, has been implicated in the pathogenesis of diverse diseases, highlighting its pivotal role in disease progression. Therefore, our study aimed to investigate the impact of pyroptosis in EMT using a comprehensive bioinformatics approach. We initially obtained two datasets from the Gene Expression Omnibus database and performed differential expression analysis to identify pyroptosis-related genes (PRGs) that were differentially expressed between EMT and non-EMT samples. Subsequently, several machine learning algorithms, namely least absolute shrinkage selection operator regression, support vector machine-recursive feature elimination, and random forest algorithms were used to identify a hub gene to construct an effective diagnostic model for EMT. Receiver operating characteristic curve analysis, nomogram, calibration curve, and decision curve analysis were applied to validate the performance of the model. Based on the selected hub gene, differential expression analysis between high- and low-expression groups was conducted to explore the functions and signaling pathways related to it. Additionally, the correlation between the hub gene and immune cells was investigated to gain insights into the immune microenvironment of EMT. Finally, a pyroptosis-related competing endogenous RNA network was constructed to elucidate the regulatory interactions of the hub gene. Our study revealed the potential contribution of a specific PRG to the pathogenesis of EMT, providing a novel perspective for clinical diagnosis and treatment of EMT.

5.
Int J Mol Sci ; 24(8)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37108814

RESUMO

Natural bioactive compounds have recently emerged as a current strategy for Alzheimer's disease treatment. Carotenoids, including astaxanthin, lycopene, lutein, fucoxanthin, crocin and others are natural pigments and antioxidants, and can be used to treat a variety of diseases, including Alzheimer's disease. However, carotenoids, as oil-soluble substances with additional unsaturated groups, suffer from low solubility, poor stability and poor bioavailability. Therefore, the preparation of various nano-drug delivery systems from carotenoids is a current measure to achieve efficient application of carotenoids. Different carotenoid delivery systems can improve the solubility, stability, permeability and bioavailability of carotenoids to a certain extent to achieve Alzheimer's disease efficacy. This review summarizes recent data on different carotenoid nano-drug delivery systems for the treatment of Alzheimer's disease, including polymer, lipid, inorganic and hybrid nano-drug delivery systems. These drug delivery systems have been shown to have a beneficial therapeutic effect on Alzheimer's disease to a certain extent.


Assuntos
Doença de Alzheimer , Humanos , Doença de Alzheimer/tratamento farmacológico , Sistemas de Liberação de Fármacos por Nanopartículas , Carotenoides/uso terapêutico , Licopeno , Luteína
6.
Pharm Res ; 38(4): 693-706, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33754258

RESUMO

PURPOSE: This study aims to overcome the challenges of the current oral targeted drug delivery system, such as the complex preparation process, poor biocompatibility, and delayed drug release. METHODS: Here, a non-covalent polymer hydrogel was prepared using the mechanochemical method, and the solid phase loading of 5-amino salicylic acid (5-ASA) was realized. RESULTS: The results obtained from the thermodynamics study, particle size analysis, and electron microscopy show that chitosan (CS) and sodium alginate (SA) form a pH-sensitive hydrogel under the mechanochemical force and also maintain good stability in aqueous solution. Fluorescent tracers study showed that the pH-sensitive hydrogel could achieve the targeted drug release in the colon and the retention time was over 12 h. Next, in vivo efficacy studies, change in mice body weight, DAI (disease activity index) score, thymus, and spleen index, and the diseased state of the mice colon revealed that the pH-sensitive hydrogel is an improved drug delivery system over 5-ASA API commercial preparations as observed in the efficacy and toxicological studies. CONCLUSION: This method uses an innovative preparation technology that without the need of cross-linking agent to produce an efficient colon-targeted drug delivery system for the treatment of ulcerative colitis.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Hidrogéis/química , Mesalamina/administração & dosagem , Administração Oral , Alginatos , Animais , Disponibilidade Biológica , Química Farmacêutica/métodos , Quitosana/química , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Sulfato de Dextrana/administração & dosagem , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Humanos , Concentração de Íons de Hidrogênio , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Masculino , Mesalamina/farmacocinética , Camundongos , Tamanho da Partícula , Ratos
7.
Acta Pharmacol Sin ; 42(1): 160-170, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32541921

RESUMO

Sorafenib is the first-line treatment of advanced hepatocellular carcinoma (HCC). However, there is a lack of validated biomarkers to predict sorafenib sensitivity. In this study we investigated the role of ACSL4, a positive-activating enzyme of ferroptosis, in sorafenib-induced cell death and HCC patient outcome. We showed that ACSL4 protein expression was negatively associated with IC50 values of sorafenib in a panel of HCC cell lines (R = -0.952, P < 0.001). Knockdown of ACSL4 expression by specific siRNA/sgRNA significantly attenuated sorafenib-induced lipid peroxidation and ferroptosis in Huh7 cells, and also rescued sorafenib-induced inhibition of xenograft tumor growth in vivo. We selected 29 HCC patients with surgery as primary treatment and sorafenib as postoperative adjunct therapy from a hospital-based cohort. A high proportion (66.7%) of HCC patients who had complete or partial responses to sorafenib treatment (according to the revised RECIST guideline) had higher ACSL4 expression in the pretreated HCC tissues, compared with those who had stable or progressed tumor growth (23.5%, P = 0.029). Since ACSL4 expression was independent of sorafenib treatment, it could serve as a useful predictive biomarker. Taken together, this study demonstrates that ACSL4 is essential for sorafenib-induced ferroptosis and useful for predicting sorafenib sensitivity in HCC. This study may have important translational impacts in precise treatment of HCC.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Coenzima A Ligases/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Animais , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Coenzima A Ligases/genética , Ferroptose/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Camundongos Endogâmicos BALB C , Prognóstico , Ensaios Antitumorais Modelo de Xenoenxerto
8.
BMC Cancer ; 20(1): 94, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32013960

RESUMO

BACKGROUND: Lymphovascular invasion (LVI) is a vital risk factor for prognosis across cancers. We aimed to develop a scoring system for stratifying LVI risk in patients with breast cancer. METHODS: A total of 301 consecutive patients (mean age, 49.8 ± 11.0 years; range, 29-86 years) with breast cancer confirmed by pathological reports were retrospectively evaluated at the authors' institution between June 2015 and October 2018. All patients underwent contrast-enhanced Magnetic Resonance Imaging (MRI) examinations before surgery. MRI findings and histopathologic characteristics of tumors were collected for analysis. Breast LVI was confirmed by postoperative pathology. We used a stepwise logistic regression to select variables and two cut-points were determined to create a three-tier risk-stratification scoring system. The patients were classified as having low, moderate and high probability of LVI. The area under the receiver operating characteristic curve (AUC) was used to evaluate the discrimination ability of the scoring system. RESULTS: Tumor margins, lobulation sign, diffusion-weighted imaging appearance, MRI-reported axillary lymph node metastasis, time to signal intensity curve pattern, and HER-2 were selected as predictors for LVI in the point-based scoring system. Patients were considered at low risk if the score was < 3.5, moderate risk if the score was 3.5 to 6.0, and high risk if the score was ≥6.0. LVI risk was segmented from 0 to 100.0% and was positively associated with an increase in risk scores. The AUC of the scoring system was 0.824 (95% confidence interval [CI]: 0.776--0.872). CONCLUSION: This study shows that a simple and reliable score-based risk-stratification system can be practically used in stratifying the risk of LVI in breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Metástase Linfática/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos
9.
Hum Biol ; 91(4): 257-277, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32767896

RESUMO

The Fujian Tanka people are officially classified as a southern Han ethnic group, whereas they have customs similar to Daic and Austronesion people. Whether they originated in Han or Daic people, there is no consensus. Three hypotheses have been proposed to explain the origin of this group: (1) the Han Chinese origin, (2) the ancient Daic origin, (3) and the admixture between Daic and Han. This study addressed this issue by analyzing the paternal Y chromosome and maternal mtDNA variation of 62 Fujian Tanka and 25 neighboring Han in Fujian. The southern East Asian predominant haplogroups (e.g., Y-chromosome O1a1a-P203 and O1b1a1a-M95, and mtDNA F2a, M7c1, and F1a1) had relatively high frequencies in Tanka. The interpopulation comparison revealed that the Tanka have a closer affinity with Daic populations than with Han Chinese in paternal lineages but are closely clustered with southern Han populations such as Hakka and Chaoshanese in maternal lineages. Network and haplotype-sharing analyses also support the admixture hypothesis. The Fujian Tanka mainly originate from the ancient indigenous Daic people and have only limited gene flows from Han Chinese populations. Notably, the divergence time inferred by the Tanka-specific haplotypes indicates that the formation of Fujian Tanka was a least 1033.8-1050.6 years before present (the early Northern Song dynasty), indicating that they are an indigenous population, not late Daic migrants from southwestern China.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional/métodos , Povo Asiático/genética , China/etnologia , DNA Mitocondrial/história , Etnicidade/genética , Feminino , Testes Genéticos/métodos , Haplótipos/genética , História Antiga , Humanos , Masculino , Polimorfismo de Nucleotídeo Único/genética
10.
J Craniofac Surg ; 31(8): 2360-2363, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33136891

RESUMO

BACKGROUND: Gene alterations are very vital when it comes to the molecular pathogenesis of glioma. In this study, there was the design of the probable candidate genes in the glioma. METHODS: Gene Expression Omnibus (GEO) database data sets of glioma tissue were retrieved and the differentially expressed genes (DEGs) from the individual microarray were merged. The following were performed: Gene Ontology; enrichment analysis; Kyoto Encyclopedia of Genes and Genomes (KEGG); pathway analysis; protein-protein interaction networks analysis. RESULTS: The following were selected: 4 GEO data sets that included 370 high-grade glioma samples as well as 169 low-grade glioma samples. Identification of a total of 174 DEGs was done. Out of the identified DEGs, 82 were upregulated and 92 were downregulated genes. According to the Gene Ontology analysis, the primary biologic focus of DEGs included passive transmembrane transporter activity, regulation of channel activity, as well as the revelation that the biologic roles of DEGs aimed primarily on regulating channel activity, as well as the monovalent inorganic cation transmembrane transporter activity. The most significant pathway in KEGG analysis was PI3K-AKT signaling pathway. Some of the significant hub genes as per the protein-protein interaction network analysis included CDC20, NDC80, DLGAP5, CENPF, CENPE, ASPM, TPX2, TOP2A, RRM2, and PRC1. CONCLUSION: From this study, it is evidenced that the use of integrated bioinformatics analyses in screening for pathways and DEGs in glioma can help us understand the clinical significance of understanding glioma, the molecular mechanism that underlies the development of glioma, as well as the provision of an effective target to treat glioma.


Assuntos
Glioma/genética , Glioma/metabolismo , Mapas de Interação de Proteínas , Transdução de Sinais , Biologia Computacional , Regulação para Baixo , Redes Reguladoras de Genes , Humanos , Regulação para Cima
11.
Opt Express ; 27(16): A1225-A1240, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31510516

RESUMO

We present the trend and seasonal variability of stratospheric NO2 column for the first time over the polluted atmosphere at Hefei, China, retrieved using Fourier transform infrared spectroscopy (FTIR) between 2015 and 2018. The FTIR observed stratospheric NO2 columns over Hefei show a peak in June and reach a minimum in January. The mean stratospheric NO2 column concentration in June is (3.49 ± 0.25) × 1015 molecules*cm-2, and is 39.20% ± 8.95% higher than that in January with a mean value of (2.51 ± 0.21) × 1015 molecules*cm-2. We find a negative trend of (-0.34 ± 0.05) %/yr in the FTIR observations of stratospheric NO2 column. The FTIR data are compared to the satellite OMI observations to assess the new data set quality and also applied to evaluate the GEOS-Chem model simulations. We find in general the OMI observations and GEOS-Chem model results are in good agreement with the coincident FTIR data, and they all show similar seasonal cycles with strong correlation coefficients of 0.84-0.86. The annual average OMI minus FTIR difference is (1.48 ± 5.33) × 1014 molecules*cm-2 (4.82% ± 17.37%), and average GEOS-Chem minus FTIR difference is (2.36 ± 2.33) × 1014 molecules*cm -2 (7.66% ± 7.49%). Their maximum differences occur in April and May with mean differences of 12-16%. We also found negative trends in the stratospheric NO2 column over Hefei for 2015-2018 with both OMI observations (-0.91 ± 0.09%/yr) and GEOS-Chem model results (-0.31 ± 0.05%/yr), demonstrating some consistency among them.

12.
Mol Cancer ; 16(1): 142, 2017 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-28830551

RESUMO

BACKGROUND: Emerging studies show that long noncoding RNAs (lncRNAs) play important roles in carcinogenesis and cancer progression. The lncRNA ZEB1 antisense 1 (ZEB1-AS1) derives from the promoter region of ZEB1 and we still know little about its expressions, roles and mechanisms. METHODS: RACE was used to obtain the sequence of ZEB1-AS1. RNA interference was used to decrease ZEB1-AS1 expression. Adenovirus expression vector was used to increase ZEB1-AS1 expression. CHIP and RIP were used to detect the epigenetic mechanisms by which ZEB1-AS1 regulated ZEB1. CCK8 assay, wound healing assay and transwell assay were used to measure proliferation and migration of prostate cancer cells. RESULTS: In this study, in prostate cancer cells, we found that RNAi-mediated downregulation of ZEB1-AS1 induced significant ZEB1 inhibition while artificial overexpression of ZEB1-AS1 rescued ZEB1 expression, which means that ZEB1-AS1 promotes ZEB1 expression. Also, ZEB1-AS1 indirectly inhibited miR200c, the well-known target of ZEB1, and upregulated miR200c's target BMI1. Mechanistically, ZEB1-AS1 bound and recruited histone methyltransferase MLL1 to the promoter region of ZEB1, induced H3K4me3 modification therein, and activated ZEB1 transcription. Biologically, ZEB1-AS1 promoted proliferation and migration of prostate cancer cells. CONCLUSIONS: Collectively, ZEB1-AS1 functions as an oncogene in prostate cancer via epigenetically activating ZEB1 and indirectly regulating downstream molecules of ZEB1.


Assuntos
Neoplasias da Próstata/metabolismo , RNA Longo não Codificante/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Epigênese Genética/genética , Humanos , Masculino , MicroRNAs/metabolismo , Neoplasias da Próstata/genética , RNA Longo não Codificante/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética
13.
Proc Natl Acad Sci U S A ; 110(5): 1720-5, 2013 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-23319651

RESUMO

Large numbers of studies have focused on the posttranslational regulation of p53 activity. One of the best-known negative regulators for p53 is MDM2, an E3 ubiquitin ligase that promotes p53 degradation through proteasome degradation pathways. Additional E3 ligases have also been reported to negatively regulate p53. However, whether these E3 ligases have distinct/overlapping roles in the regulation of p53 is largely unknown. In this study, we identify RNF2 (ring finger protein 2) as an E3 ligase that targets p53 for degradation. The E3 ligase activity of RNF2 requires Bmi1 protein, a component of the polycomb group (PcG) complex. The up-regulation of p53 does not affect RNF2 expression. Unlike Mdm2, RNF2 only degrades p53 in selective cell lines, such as those from germ-cell tumors. The knockdown of RNF2 induces apoptosis, which can be rescued through the reduction of p53 expression. Moreover, the down-regulation of RNF2 expression in germ-cell tumors significantly reduces tumor cell growth, while the simultaneous down-regulation of both genes restores tumor cell growth in vitro and in tumor xenograft models. Furthermore, a reverse correlation between RNF2 and p53 expression was detected in human ovarian cancer tissues. Together, these results indicate that RNF2 is an E3 ligase for p53 degradation in selective cells, implicating RNF2 as a therapeutic target to restore tumor suppression through p53 in certain tumor cells.


Assuntos
Complexo Repressor Polycomb 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Feminino , Células HCT116 , Células HEK293 , Células HT29 , Células HeLa , Células Hep G2 , Humanos , Immunoblotting , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Complexo Repressor Polycomb 1/genética , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/genética , Carga Tumoral/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
14.
Prostate ; 75(8): 855-62, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25683382

RESUMO

BACKGROUND: The downregulation of the tumor suppressor miR200c plays important roles in many malignant tumors. This study aims to show that miR200c is a posttranscriptional regulator of insulin receptor substrate 1 (IRS1) and over-expression of miR200c suppresses prostate cancer cell growth. METHODS: Bioinformatics analysis was used to show potential post-translational regulation of IRS1 by miR200c. Dual reporter gene assays were chosen to test the binding of miR200c to the potential seed sequences in IRS1 3'UTR. RT-PCR, Q-PCR and western blot were applied to determine the regulation effect of miR200c on IRS1. CCK8 assay, soft agar assay, trypan blue exclusion assay and flow cytometric analysis were used to measure the biological effects of miR200c on prostate cancer cell proliferation and apoptosis. RESULTS: The 449-455 nt, 3061-3067 nt, and 3096-3102 nt of the IRS1 3'-UTR were identified as three potential seed sequences for miR200c. MiR200c directly binds to IRS1 through the seed sequences in IRS1 3'-UTR. Artificial overexpression of miR200c significantly downregulated the mRNA and protein levels of IRS1, together with decreased cell proliferation and increased cell death of PC3 and DU145 cells. CONCLUSIONS: Our results suggest that miR200c plays crucial roles in prostate cancer by post-transcriptional regulation of IRS1. The mir200c/IRS1 pathway may be a potential therapeutic target to prevent prostate cancer cell growth.


Assuntos
Crescimento Celular , Proteínas Substratos do Receptor de Insulina/biossíntese , MicroRNAs/biossíntese , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/prevenção & controle , Apoptose/fisiologia , Morte Celular/fisiologia , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/patologia , RNA Mensageiro/biossíntese
15.
Development ; 139(24): 4591-600, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23136389

RESUMO

The precise formation of three-dimensional motor circuits is essential for movement control. Within these circuits, motoneurons (MNs) are specified from spinal progenitors by dorsoventral signals and distinct transcriptional programs. Different MN subpopulations have stereotypic cell body positions and show specific spatial axon trajectories. Our knowledge of MN axon outgrowth remains incomplete. Here, we report a zebrafish gene-trap mutant, short lightning (slg), in which prdm14 expression is disrupted. slg mutant embryos show shortened axons in caudal primary (CaP) MNs resulting in defective embryonic movement. Both the CaP neuronal defects and behavior abnormality of the mutants can be phenocopied by injection of a prdm14 morpholino into wild-type embryos. By removing a copy of the inserted transposon from homozygous mutants, prdm14 expression and normal embryonic movement were restored, confirming that loss of prdm14 expression accounts for the observed defects. Mechanistically, Prdm14 protein binds to the promoter region of islet2, a known transcription factor required for CaP development. Notably, disruption of islet2 function caused similar CaP axon outgrowth defects as observed in slg mutant embryos. Furthermore, overexpression of islet2 in slg mutant embryos rescued the shortened CaP axon phenotypes. Together, these data reveal that prdm14 regulates CaP axon outgrowth through activation of islet2 expression.


Assuntos
Axônios/fisiologia , Proteínas com Homeodomínio LIM/genética , Neurônios Motores/fisiologia , Proteínas Repressoras/fisiologia , Transativadores/fisiologia , Fatores de Transcrição/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Animais , Animais Geneticamente Modificados , Axônios/metabolismo , Embrião não Mamífero , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas com Homeodomínio LIM/metabolismo , Proteínas com Homeodomínio LIM/fisiologia , Neurônios Motores/metabolismo , Rede Nervosa/embriologia , Rede Nervosa/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais/genética , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Transcrição Gênica/genética , Peixe-Zebra/genética , Peixe-Zebra/fisiologia , Proteínas de Peixe-Zebra/metabolismo
16.
J Med Virol ; 87(3): 366-74, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25154318

RESUMO

Although the National Free Antiretroviral Treatment Program (NFATP) has resulted in a significant reduction in the incidence of AIDS-defining illnesses in China, severe complications in patients infected with HIV may require aggressive treatment and critical care support. The objective for this study was to investigate the etiology and outcomes of patients infected with HIV admitted to intensive care units in Ditan Hospital, China. The evaluation of the etiology and outcomes of patients infected with HIV admitted to intensive care units was conducted using the clinical data from 122 patients infected with HIV (129 occasions) admitted to the Beijing Ditan hospital from January 1, 2009, to October 1, 2013. Over the five-year study period, 129 occasions occurred for 122 patients infected with HIV admitted to intensive care units. Respiratory failure was the most common condition (53.4%) among the 129 occasions analyzed. This was followed by pneumothorax (12.4%), infectious shock (8.5%), neurological problems (8.5%), renal failure (7.8%), post-operative complications and trauma (5.4%), coronary heart disease (3.1%), adverse effects of HAART (3.1%), lymphoma (2.4%), and liver failure (0.8%). Mortality in intensive care units was 64.5% while in-hospital mortality was 65.9%. The strongest protective predictor for in-hospital mortality was earlier admission to an intensive care unit (OR = 0.050, CI = 0.020-0.126, P < 0.001). Respiratory failure was the most common condition in patients infected with HIV admitted to intensive care units, and the outcome for the patients was poor. Mortality was negatively associated with earlier admission to an intensive care unit, but was not associated with HAART.


Assuntos
Estado Terminal/epidemiologia , Infecções por HIV/complicações , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Centros de Atenção Terciária , Resultado do Tratamento , Adulto Jovem
17.
Opt Express ; 23(1): 110-20, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25835658

RESUMO

In this paper, we propose a novel microfluidic tunable metamaterial (MM) absorber printed on a paper substrate in silver nanoparticle ink. The metamaterial is designed using a periodic array consisting of square patches. The conductive patterns are inkjet-printed on paper using silver nanoparticle inks. The microfluidic channels are laser-etched on polymethyl methacrylate (PMMA). The conductive patterns on paper and the microfluidic channels on PMMA are bonded by an SU-8 layer that is also inkjet-printed on the conductive patterns. The proposed MM absorber provides frequency-tuning capability for different fluids in the microfluidic channels. We performed full-wave simulations and measurements that confirmed that the resonant frequency decreased from 4.42 GHz to 3.97 GHz after the injection of distilled water into the microfluidic channels. For both empty and water-filled channels, the absorptivity is higher than 90% at horizontal and vertical polarizations.

18.
Bioorg Med Chem Lett ; 24(21): 4995-8, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25278238

RESUMO

Two new spirooxindole alkaloids spindomycins A (1) and B (2) were isolated from rhizosphere strain Streptomyces sp. xzqh-9. Their structures were elucidated by comprehensive spectroscopic analyses of NMR and MS data. The absolute configurations of 1 and 2 were determined by experimental and theoretical calculation of electronic circular dichroism (ECD). Antitumor, lactate dehydrogenase, and tyrosine kinase inhibitory activities of two compounds were evaluated, while only spindomycin B (2) exhibited weak inhibitory activity against tyrosine kinase Bcr-Abl.


Assuntos
Alcaloides Indólicos/farmacologia , Indóis/química , Rizosfera , Compostos de Espiro/química , Streptomyces/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Dicroísmo Circular , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/isolamento & purificação , Concentração Inibidora 50 , L-Lactato Desidrogenase/metabolismo , Estrutura Molecular , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Ressonância Magnética Nuclear Biomolecular , Oxindóis , Inibidores de Proteínas Quinases/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Compostos de Espiro/isolamento & purificação , Compostos de Espiro/farmacologia , Células Tumorais Cultivadas
19.
Nat Commun ; 15(1): 3256, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627399

RESUMO

Spacer acquisition step in CRISPR-Cas system involves the recognition and subsequent integration of protospacer by the Cas1-Cas2 complex in CRISPR-Cas systems. Here we report an anti-CRISPR protein, AcrVA5, and reveal the mechanisms by which it strongly inhibits protospacer integration. Our biochemical data shows that the integration by Cas1-Cas2 was abrogated in the presence of AcrVA5. AcrVA5 exhibits low binding affinity towards Cas2 and acetylates Cas2 at Lys55 on the binding interface of the Cas2 and AcrVA5 N-terminal peptide complex to inhibit the Cas2-mediated endonuclease activity. Moreover, a detailed structural comparison between our crystal structure and homolog structure shows that binding of AcrVA5 to Cas2 causes steric hindrance to the neighboring protospacer resulting in the partial disassembly of the Cas1-Cas2 and protospacer complex, as demonstrated by electrophoretic mobility shift assay. Our study focuses on this mechanism of spacer acquisition inhibition and provides insights into the biology of CRISPR-Cas systems.


Assuntos
Proteínas Associadas a CRISPR , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas
20.
Medicine (Baltimore) ; 103(12): e37523, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518032

RESUMO

BACKGROUND: Previous research has indicated that the rupture of intracranial aneurysm (IA) is a significant contributor to mortality from stroke. The objective of this present study was to examine the infiltration patterns in ruptured intracranial aneurysm (RIA), with the aim of generating insights that could inform the development of effective immunotherapeutic approaches. METHODS: To achieve this, we obtained Gene Expression Omnibus datasets pertaining to ruptured aneurysms, encompassing a total of 19 unruptured intracranial aneurysms (UIA) and 27 RIA. Subsequently, we conducted differential gene analysis and immune cell analysis specifically for the RIA. RESULTS: According to the conducted studies, the analysis has identified 10 hub genes within key modules. Through the utilization of Kyoto Encyclopedia of Genes and Genomes pathway and gene ontology terms analyses, it has been established that genes exhibiting differential expression are associated with immune cell infiltration in the aneurysm wall. Furthermore, the implementation of the CIBERSORT algorithm has revealed that there are 22 distinct immune cells between RIA and tissues of UIA. IA samples contained a higher proportion of macrophages M1, mast cells resting, and CD4 naive T cells, while macrophages M0 and neutrophils were relatively lower in RIA compared with those in UIA. CONCLUSION: The current study initially identified highly conservative hub genes and immune cell infiltration patterns in IA. Data presented in the current study improved understanding of immune genes that drive IA which can be exploited in development of effective immunotherapies.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Humanos , Aneurisma Intracraniano/genética , Aneurisma Roto/genética , Aneurisma Roto/metabolismo
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