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1.
J Biol Chem ; 299(10): 105192, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37625589

RESUMO

Point mutations in leucine-rich repeat kinase 2 (LRRK2) cause Parkinson's disease and augment LRRK2's kinase activity. However, cellular pathways that endogenously enhance LRRK2 kinase function have not been identified. While overexpressed Rab29 draws LRRK2 to Golgi membranes to increase LRRK2 kinase activity, there is little evidence that endogenous Rab29 performs this function under physiological conditions. Here, we identify Rab38 as a novel physiologic regulator of LRRK2 in melanocytes. In mouse melanocytes, which express high levels of Rab38, Rab32, and Rab29, knockdown (or CRISPR knockout) of Rab38, but not Rab32 or Rab29, decreases phosphorylation of multiple LRRK2 substrates, including Rab10 and Rab12, by both endogenous LRRK2 and exogenous Parkinson's disease-mutant LRRK2. In B16-F10 mouse melanoma cells, Rab38 drives LRRK2 membrane association and overexpressed kinase-active LRRK2 shows striking pericentriolar recruitment, which is dependent on the presence of endogenous Rab38 but not Rab32 or Rab29. Consistently, knockdown or mutation of BLOC-3, the guanine nucleotide exchange factor for Rab38 and Rab32, inhibits Rab38's regulation of LRRK2. Deletion or mutation of LRRK2's Rab38-binding site in the N-terminal armadillo domain decreases LRRK2 membrane association, pericentriolar recruitment, and ability to phosphorylate Rab10. In sum, our data identify Rab38 as a physiologic regulator of LRRK2 function and lend support to a model in which LRRK2 plays a central role in Rab GTPase coordination of vesicular trafficking.


Assuntos
Membranas Intracelulares , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina , Melanócitos , Proteínas rab de Ligação ao GTP , Animais , Camundongos , Complexo de Golgi/enzimologia , Complexo de Golgi/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Melanócitos/metabolismo , Mutação , Doença de Parkinson/metabolismo , Fosforilação , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Expressão Gênica , Domínios Proteicos , Ligação Proteica , Membranas Intracelulares/metabolismo
2.
J Med Virol ; 92(1): 26-33, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31475732

RESUMO

This study aimed to assess the clinical characteristics and T-helper 1 (Th1)/Th2 profile of human rhinovirus (HRV) infection in children with bronchiolitis and pneumonia, compared with the respiratory syncytial virus (RSV). In September 2013 to August 2014, 335 nasopharyngeal aspirates from children below 14 with bronchiolitis and pneumonia were screened for HRV and 13 other respiratory viruses by PCR or reverse transcription PCR. Interferon (IFN)-γ, interleukin (IL)-2, IL-4, IL-6, IL-10, and tumor necrosis factor (TNF)-α were detected by multiplex enzyme-linked immunosorbent assay. HRVs were found in 66 cases (19.7%), including 35 bronchiolitis and 31 pneumonia cases. Compared with the RSV alone group, children with pneumonia had more frequent wheezing episodes in HRV (Pa = .001) and HRV + non-RSV (Pb = .002) groups, and fever in the HRV (Pf = .004) and HRV + RSV (Pg = .005) groups. Among patients with bronchiolitis, cases with HRV alone were more likely to present in winter than those with RSV alone (Pi = .010) and HRV + non-RSV (Pj = .014), and less numerous in summer compared with HRV + non-RSV (Ph = .005). Children with HRV alone were more susceptible to have a history of eczema than RSV alone among bronchiolitis (Pc < .001) and pneumonia (Pe = .033) cases. HRV bronchiolitis cases had increased IL-4/IFN-γ and decreased TNF-α/IL-10 ratios, compared with HRV pneumonia counterparts. HRV is a major non-RSV pathogen causing hospitalization in children with bronchiolitis and pneumonia and induces an imbalanced Th1/Th2 response in bronchiolitis. Compared with RSV infection, HRV bronchiolitis and pneumonia differ significantly regarding wheezing episodes, susceptibility to eczema, fever occurrence, and seasonal prevalence.


Assuntos
Hospitalização/estatística & dados numéricos , Infecções por Picornaviridae/imunologia , Células Th1/imunologia , Células Th2/imunologia , Adolescente , Bronquiolite/imunologia , Bronquiolite/virologia , Criança , Pré-Escolar , Citocinas/imunologia , Eczema , Feminino , Febre/virologia , Humanos , Lactente , Recém-Nascido , Masculino , Nasofaringe/virologia , Pneumonia Viral/imunologia , Sons Respiratórios , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano , Rhinovirus , Índice de Gravidade de Doença
3.
Front Oncol ; 11: 651535, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868902

RESUMO

INTRODUCTION: Malignant proliferation and metastasis are some of the causes of high mortality in pancreatic cancer. MicroRNAs have been a hot spot in cancer research and are involved in tumor formation and metabolic stress responses. However, the biology function and underlying mechanism of miRNA regulating pancreatic cancer progress is remained uncleared. METHODS: RNA-seq analysis the glycolysis associated miRNAs and verified miRNA-489-3p was involving in glycolysis. We used RNA in situ hybridization (ISH) and qRT-PCR to analyze the differential expression of miR-489-3p in pancreatic cancer tissues and adjacent tissues and cell lines. Then the function assay of in vivo and in vitro were used to evaluated the role of miR-489-3p in the proliferation, metastasis and glucose metabolism of pancreatic cancer. Furthermore, dual luciferase reporter and rescue experiments were performed to explore the mechanism underlying in the role of miRNA-489-3p. RESULTS: We determined that glycolysis associated miRNA miR-489-3p was downregulated in pancreatic cancer tissues and cell lines. The gain and loos of function experiments confirmed that miR-489-3p could inhibit the proliferation, metastasis and glucose metabolism of pancreatic cancer. Further, we found that miR-489-3p could target regulating LDHA and PKM through the luciferase report experiment. Finally, in vivo experiment confirmed that highly expressed miR-489-3p inhibited the growth of pancreatic cancer. CONCLUSION: In short, this study identified miR-489-3p as a novel therapy target for pancreatic cancer which was involving in the proliferation, metastasis and glycolysis, but its diagnostic value deserves further study.

4.
Exp Ther Med ; 20(2): 890-900, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32742331

RESUMO

Human hepatocellular carcinoma (HCC) is a common malignant tumor of the digestive tract that is prevalent worldwide. Improving diagnosis methods for HCC helps to improve patient survival rate. The present study aimed to identify novel HCC biomarkers for the diagnosis of HCC through analyzing gene changes on peripheral blood mononuclear cells (PBMCs) and verifying these in additional samples. The gene expression profiles GSE49515 (including 10 specimens from normal patients and 10 specimens from patients with HCC) and GSE58208 (including 5 specimens from normal patients and 10 specimens from patients with HCC) were downloaded from the online Gene Expression Omnibus database (GEO). Differentially expressed genes (DEGs) in PBMCs between healthy controls and patients with HCC were identified using R software. A total of 935 DEGs, including 686 upregulated DEGs and 249 downregulated DEGs, were identified in the present study. In order to identify any internal associations, these DEGs were used to construct weighted gene co-expression networks (WGCNA). Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis of genes in each module were conducted using the online database DAVID. Furthermore, hub genes with high module membership were identified in a co-expression network and receiver operating characteristic curves were used to verify the diagnostic values of these eight hub genes. Furthermore, the expression and diagnosis value of the eight hub genes were also verified in additional samples. The results of the present study suggested that secreted protein acidic and cysteine rich(SPARC), transmembrane protein 40 (TMEM40), solute carrier family 25 member 44, formyl peptide receptor 2 (FPR2), complement C8 ß chain, N-myristoyltransferase 1, protein kinase C δ(PRKCD) and protein phosphatase, Mg2+/Mn2+ dependent 1M(PPM1M) were hub genes. SPARC, TMEM40, FPR2, PRKCD and PPM1M had prominent diagnostic value according to the results from the GEO data and the additional samples. The present study demonstrated that these hub genes may help to improve the diagnosis of HCC.

5.
Oncol Lett ; 20(1): 483-494, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32565973

RESUMO

The present study aimed to identify the key genes that are associated with the progression of intrahepatic cholangiocarcinoma through weighted gene co-expression network analysis (WGCNA). A total of three gene datasets were downloaded from the Gene Expression Omnibus database, including GSE107943, GSE119336 and GSE26566. Differentially expressed genes (DEGs) between intrahepatic cholangiocarcinoma tissues and adjacent liver tissues were identified using GSE107943, while tissue specific genes between bile duct and liver tissues were identified using GSE26566. Following the removal of tissue-specific genes, real DEGs were used to construct the WGCNA to investigate the association between gene modules and clinical traits. Following functional analysis, pathway enrichment analysis and the construction of a protein-protein interaction (PPI) network were performed, hub genes were selected and their diagnostic value was verified in GSE119336 using a receiver operating characteristic curve. Finally, the protein levels of the hub genes were also verified in intrahepatic cholangiocarcinoma tissues. A total of 1,643 real DEGs were identified and used to construct the WGCNA. Additionally, a total of seven co-expressed gene modules were identified following WGCNA, while genes in brown and yellow modules were identified to be associated with multiple clinical traits (the number of clinical traits >3) and used as key modules. A total of 63 core key module genes were subsequently identified, and it was indicated that these genes were most enriched in the nucleus (Gene Ontology term) and the cell cycle pathway (Kyoto Encyclopedia of Genes and Genomes term). Finally, a total of eight genes, including cyclin B1, cell division cycle 20, cell division cycle associated 8, cyclin dependent kinase 1, centrosomal protein 55, kinesin family member 2C, DNA topoisomerase IIα and TPX2 microtubule nucleation factor, exhibited the highest score in PPI analysis and had a high diagnostic value for intrahepatic cholangiocarcinoma. In addition, the protein levels of these genes were also revealed to be increased in most intrahepatic cholangiocarcinoma tissues. These eight genes may be used as novel biomarkers for the diagnosis of intrahepatic cholangiocarcinoma.

6.
J Exp Clin Cancer Res ; 38(1): 470, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31747939

RESUMO

BACKGROUND: Accumulation evidence indicates the vital role of long non-coding RNAs (lncRNAs) in tumorigenesis and the progression of malignant tumors, including pancreatic cancer (PC). However, the role and the molecular mechanism of long non-coding RNA 00976 is unclear in pancreatic cancer. METHODS: In situ hybridization (ISH) and qRT-PCR was performed to investigate the association between linc00976 expression and the clinicopathological characteristics and prognosis of patients with PC. Subsequently, linc00976 over-expression vector and shRNAs were transfected into PC cells to up-regulate or down-regulate linc00976 expression. Loss- and gain-of function assays were performed to investigate the role of linc00976 in proliferation and metastasis in vitro and vivo. ITRAQ, bioinformatic analysis and rescue assay were used to illustrate the ceRNA mechanism network of linc00976/miR-137/OTUD7B and its downstream EGFR/MAPK signaling pathway. RESULTS: linc00976 expression was overexpressed in PC tissues and cell lines and was positively associated with poorer survival in patients with PC. Function studies revealed that linc00976 knockdown significantly suppressed cell proliferation, migration and invasion in vivo and in vitro, whereas its overexpression reversed these effects. Based on Itraq results and online database prediction, Ovarian tumor proteases OTUD7B was found as a downstream gene of linc00976, which deubiquitinated EGFR mediates MAPK signaling activation. Furthermore, Bioinformatics analysis and luciferase assays and rescue experiments revealed that linc00976/miR137/OTUD7B established the ceRNA network modulating PC cell proliferation and tumor growth. CONCLUSION: The present study demonstrates that linc00976 enhances the proliferation and invasion ability of PC cells by upregulating OTUD7B expression, which was a target of miR-137. Ultimately, OTUD7B mediates EGFR and MAPK signaling pathway, suggesting that linc00976/miR-137/OTUD7B/EGFR axis may act as a potential biomarker and therapeutic target for PC.


Assuntos
Endopeptidases/metabolismo , Sistema de Sinalização das MAP Quinases , MicroRNAs/metabolismo , Neoplasias Pancreáticas/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Linhagem Celular Tumoral , Progressão da Doença , Endopeptidases/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Xenoenxertos , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , Transfecção
7.
Onco Targets Ther ; 12: 4081-4092, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239700

RESUMO

Purpose: Ornithine decarboxylase 1 (ODC1)-an oncogene involved in the biosynthesis of polyamines-is commonly upregulated and associated with poor prognosis in numerous cancers. However, the role and mechanism of ODC1 in hepatocellular carcinoma (HCC) remains unclear. The aim of the present study was to investigate the role of ODC1 in HCC and clarify the latent molecular mechanisms. Material and methods: We used samples obtained from The Cancer Genome Atlas. The expression of ODC1 was also assessed in our additional HCC samples and HCC cell lines. The roles of ODC1 in HCC cell proliferation, migration and invasion in vitro were investigated using the cell-counting kit-8 assay, 5-ethynyl-2´-deoxyuridine assay, colony formation assay, flow cytometry, wound healing assay and transwell assay, respectively. The effect of ODC1 on HCC cell proliferation in vivo was investigated by constructing a xenotransplanted tumor model in nude mice. Quantitative real-time polymerase chain and western blotting were used to detect the expression levels of ODC1 in mimetic hypoxia, nutrient depleted, and acidotic microenvironment. The relationships between ODC1, the AKT/GSK3ß/ß-catenin pathway, and acidotic microenvironment were further investigated through western blotting, immunohistochemical staining, and immunofluorescence. Results: ODC1 was upregulated in HCC tissues and cell lines, and co-expressed with KI67 and PCNA (P<0.05). A decrease in the expression of ODC1 inhibits proliferation, migration, invasion, and induces cell cycle arrest in HCC cell lines in vitro, while suppressing HCC cell proliferation in vivo (P<0.05). Furthermore, the expression of ODC1 was increased in the mimetic acidotic microenvironment, while the interference with the expression of ODC1 reversed the effect of the acidotic microenvironment through regulation of AKT/GSK3ß/ß-catenin and related downstream proteins. Conclusion: ODC1 is an unfavorable gene in HCC patients,promoting HCC cell proliferation, migration and invasion via the AKT/GSK3ß/ß-catenin pathway and modulation of the acidotic microenvironment.

8.
IEEE Trans Cybern ; 48(5): 1406-1419, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-28475073

RESUMO

Video decolorization is to filter out the color information while preserving the perceivable content in the video as much and correct as possible. Existing methods mainly apply image decolorization strategies on videos, which may be slow and produce incoherent results. In this paper, we propose a video decolorization framework that considers frame coherence and saves decolorization time by referring to the decolorized frames. It has three main contributions. First, we define decolorization proximity to measure the similarity of adjacent frames. Second, we propose three decolorization strategies for frames with low, medium, and high proximities, to preserve the quality of these three types of frames. Third, we propose a novel decolorization Gaussian mixture model to classify the frames and assign appropriate decolorization strategies to them based on their decolorization proximity. To evaluate our results, we measure them from three aspects: 1) qualitative; 2) quantitative; and 3) user study. We apply color contrast preserving ratio and C2G-SSIM to evaluate the quality of single frame decolorization. We propose a novel temporal coherence degree metric to evaluate the temporal coherence of the decolorized video. Compared with current methods, the proposed approach shows all around better performance in time efficiency, temporal coherence, and quality preservation.

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