1.Effect and mechanism of xCT on invasion and migration of nasopharyngeal carcinoma cells in vitro
Yafei LI ; Chengkun WANG ; Bo PENG ; Yixue GU ; Zhimin HE
Journal of Chinese Physician 2014;16(9):1181-1185
Objective To explore the role of xCT in the metastasis and drug resistance of nasopharyngeal carcinoma (NPC),to provide new evidences for the mechanism of NPC metastasis and drug resistance,and to enhance effects of chemotherapy.Methods Fluorescence quantitative polymerase chain reaction (PCR) and Western blot were used to detect the xCT expression of 5-8F and 6-10B.The xCT eukaryotic expression vector was constructed to transient transfect 6-10B cell lines.The 5-8F cell lines were treated with xCT antisense oligodeoxynucleotide (ASO).Scratching assay and transwell method were used to detect the cell metastasis and invasion abilities.The expressions of matrix metalloproteinase 1 (MMP1) of all the cell lines were surveyed by Western blot.Results The results of fluorescence quantitative PCR and Western blot showed that the expression of xCT in 5-8F was higher than 6-10B in the levels of mRNA and protein.Exogenous overexpression of xCT enhanced metastasis and invasion abilities of 6-10B cells.Silencing and inhibition of xCT could decrease metastasis and invasion abilities of 5-8F cells.The expressions of MMP1 protein in 5-8F were higher than 6-10B,and they were positively correlated with the expression of xCT.Conclusions xCT is closely related to the metastasis and invasion abilities of nasopharyngeal carcinoma.xCT could enhance the metastasis and invasion abilities of NPC cells.xCT might mediate proliferation and matastasis/invasion of NPC cells through MMP1.
2.FGF-21 Improves Glucose Uptake and Glycogen Synthesis of Insulin-resistant Liver Cells
Mingyao LIU ; Wenfei WANG ; Yixue YU ; Yuting HOU ; Guiping REN ; Deshan LI
Progress in Biochemistry and Biophysics 2006;0(10):-
Insulin resistance in insulin sensitive organ results in metabolic disorder such as hyperglycemia, hyperinsulinemia and hyper triglyceridemia which are common features of type 2 diabetes.Insulin resistance in liver cells mainly causes impaired glycogen synthesis, failed to suppress glucose production which is the major contribution to hyperglycemia.FGF-21 as a new metabolic regulator can control fasting blood glucose.The mechanism of FGF-21 effects on regulating plasma glucose has little to known.In order to establish an in vitro insulin resistant model of liver cells and evaluate the effects and mechanism of FGF-21 on glucose metabolism in the cell model, HepG2 cells were incubated with 10-7 mol/L insulin for 24 h to build insulin-resistant cell model.To evaluate the cells for insulin resistance, the cells were stimulated with fresh insulin for 24 h and the glucose uptake by these cells was carried out.The insulin-resistant cells were treated with different concentrations of FGF-21 for 24 h and insulin-treated cells were used as a control.The glucose uptake by the cells was detected by the method of glucose oxidizes/peroxides(GOD-POD);the synergy between insulin and FGF-21 was evaluated.The mRNA expression of GLUT1 in the insulin-resistant cells was detected by the real-time PCR.Glycogen synthesis of the cells was examined by the anthrone method.The results showed that HepG2 cells treated with 10-7 mol/L insulin for 24 h became resistant to insulin and the insulin resistance status was maintained for 48 h without change of cell morphology.FGF-21 could stimulate glucose consumption of the insulin-resistant model in a dose-dependent manner.The glucose consumption and glycogen synthesis of the insulin-resistant model were significantly improved by FGF-21 treatment.FGF-21 showed strong synergy with insulin in glucose uptake and glycogen synthesis of the model cells.While the cells became resistant to insulin, FGF-21 could increase the mRNA expression of GLUT1.Thus, It is concluded that FGF-21 stimulates glucose uptake in insulin resistant HepG2 cells through GLUT1 expression, stimulates glycogen synthesis and improves the glucose metabolism in the insulin resistant liver cell model.
3.Effects of shikonin on stemness maintance of glioma stem cells
Jing LIU ; Zuke DA ; Zhen LI ; Yixue XUE ; Libo LIU ; Ping WANG ; Yunhui LIU
Chinese Pharmacological Bulletin 2016;(1):49-54
Aim To explore the effect of shikonin on stemness maintance of glioma stem cells ( GSCs ). Methods After the U87-MG cells were cultured and isolated, the sphere cells were identified by immuno-fluorescent staining. The alteration of stemness of GSCs by shikonin treatment(2 μmol·L - 1 ) for 12 h, 24 h and 48 h was valued by morphological detection using optical microscope and sub-sphere forming assay. Mo-reover, the related markers of stem cells, such as CD133, were detected in shikonin treated GSCs by western blot assay. Protein expression of PI3K, p-PI3K, Akt and p-Akt was detected by western blot af-ter shikonin treatment alone. Furthermore, by combi-nation with insulin-like growth factor-1 ( IGF-1), we observed the alteration of stemness maintance of shiko-nin-treated GSCs. Results The presence of neural stem cell related markers CD133 and nestin proved the characteristics of GSCs. Shikonin treatment significant-ly inhibited the morphology of GSCs and the sub-sphere forming. Besides, the reduced expression of CD133 was detected in shikonin treated GSCs. Though, the expression of PI3K and Akt did not change compared with the control group, the expression of p-PI3K and p-Akt was reduced. Furthermore, the combination of IGF-1 markedly attenuated the inhibitory effect of shikonin on stemness maintance of GSCs. Conclusion The stemness maintance of GSCs can be significantly inhibited by shikonin treatment, in which PI3K/ Akt pathway is involved.
4.Signaling mechanisms in endothelial monocyte-activating polypeptide-Ⅱ-enhanced permeability of the blood-tumor barrier
Zhen LI ; Xiaobai LIU ; Yunhui LIU ; Yixue XUE ; Ping WANG ; Libo LIU
Chinese Pharmacological Bulletin 2014;(5):632-637
Aim To investigate the signaling mecha-nisms in endothelial monocyte-activating polypeptide-Ⅱ( EMAP-Ⅱ)-induced increase in blood-tumor barri-er ( BTB ) permeability. Methods Relatively pure cerebral microvessel fragments were obtained from the cortex of 3-5 days old Wistar rats by using careful dis-section, enzyme digestion, and dextran centrifugation. Then, these fragments were seeded on dishes and cul-tured primarily. In vitro BTB models were constructed by co-cultivation of rat brain microvascular endothelial cells ( BMECs) with C6 glioma cells. Confluent mono-layers of co-cultured BMECs were divided randomly in-to 5 groups ( each n=6 ): control, EMAP-Ⅱ, H7 +EMAP-Ⅱ, C3 exoenzyme + EMAP-Ⅱ, and C3 ex-oenzyme + H7 + EMAP-Ⅱ groups. Transendothelial electric resistance values and horseradish peroxidase flux were measured to evaluate changes in the BTB permeability . The expression levels of tight junction-re-lated protein occludin and ZO-1 in BMECs were meas-ured by Western blot. Immunofluorescence was used to identify the expression and distribution of occludin and ZO-1 in BMECs. Also, Western blot were used to de-tect the expression levels of myosin light chain ( MLC) and phosphomyosin light chain ( pMLC ) in BMECs. Results Compared with control group, the BTB per-meability of EMAP-Ⅱ group was increased significant-ly. The expression levels of occludin and ZO-1 in BMECs were significantly decreased, accompanied with marked increase in the expression level of pMLC. These above-mentioned effects of EMAP-Ⅱ were sig-nificantly inhibited by pretreatment with H7 ( an inhib-itor of PKC ) or/and C3 exoenzyme ( an inhibitor of RhoA ) . Conclusion Signaling molecules PKC and RhoA play important roles in EMAP-Ⅱ-induced in-crease in BTB permeability; signaling pathways PKC-pMLC and RhoA-pMLC are involved in this process.
5.Relationship of hypoxia inducible factor 1? and vascular endothelial growth factor expression with angiogenesis in gastric carcinoma
Yixue GU ; Hanxian LI ; Yin KAN ; Hanqun WAN ; Zhihan TANG ; Tianshu GAO
Journal of Chinese Physician 2001;0(03):-
Objective To investigate the expression of hypoxia inducible factor 1?(HIF-1?),vascular endothelial growth factor(VEGF) and micro vessel density(MVD) in gastric carcinoma and to explore their correlation with clinical pathological features such as cancer invasion and metastasis.Methods Forty-eight samples of gastric carcinoma tissues were examined for the expression of HIF-1?,VEGF and CD34 by immunohistochemical method.Results The positive expression rates of HIF-1? and VEGF were 66.7% and 60.4% in gastric carcinoma respectively.The mean value of MVD was 42.5?14.7 in gastric carcinoma.The expressions of HIF-1?,VEGF and the value of MVD were significantly correlated with the depth of invasion,lymph node metastasis and TNM stage.The HIF-1? expression was positively correlated with VEGF expression and MVD value.Conclusion The overexpression of HIF-1?,VEGF and MVD consist in gastric carcinoma tissue.The HIF-1? expression is positively correlated with VEGF expression and MVD value.The overexpression of HIF-1?,VEGF and MVD value are closely related with invasion,metastasis and poor biological behavior of gastric carcinoma.
6.A Brief Review of Computational Gene Prediction Methods
Wang ZHUO ; Chen YAZHU ; Li YIXUE
Genomics, Proteomics & Bioinformatics 2004;2(4):216-221
With the development of genome sequencing for many organisms, more and more raw sequences need to be annotated. Gene prediction by computational methods for finding the location of protein coding regions is one of the essential issues in bioinformatics. Two classes of methods are generally adopted: similarity based searches and ab initio prediction. Here, we review the development of gene prediction methods, summarize the measures for evaluating predictor quality, highlight open problems in this area, and discuss future research directions.
7.Study on immunogenicity of recombinant lentivirus expressing trimeric HA of swine H1 N1 influenza virus
Yingqi DENG ; Junfeng LI ; Hui QU ; Yubo TANG ; Yixue SUN ; Xin LI ; Weili WANG ; Zhuang DING ; Yanlong CONG
Chinese Journal of Immunology 2016;32(7):983-987
Objective:To evaluate the protective immunity by vaccination of BALB/c mice with rLV-HA-GCN4,a recombinant lentivirus expressing the trimeric HA of swine H1N1 influenza virus. Methods:The female mice were randomly divided into rLV-HA-GCN4,rLV-HA,LV and PBS groups. Mice were primed with plasmid and boosted with lentivirus by the administration of intramuscular thigh injections at an interval of two weeks. At day 28 post-prime immunization,mice were inoculated intranasally with 100TCID50 of swine H1N1 influenza virus in a 50 μl volume. The immune levels were assessed by the T lymphocyte transformation test, flow cytometry,indirect ELISA and the indexes of spleen and lung. Results:The spleen lymphocyte transformation rate was 0. 3±0. 11 in the rLV-HA-GCN4 group at day 14 post-boost immunization, showing a statistical significance ( P<0. 01 ) compared to the PBS group. Meanwhile,rLV-HA-GCN4 could cause T lymphocyte response mainly based on the Th1-type CD4+ T cells. The IgG antibody titer reached to 1:8 000 at day 14 post-boost immunization and approximately 1:7 000 at day 14 post challenge. After challenge,the spleen and lung indexes of rLV-HA-GCN4 group were significantly lower than those of PBS group (P<0. 05). The body weight of rLV-HA-GCN4 group demonstrated a slight decrease before 3 days post challenge and then a gradual increase compared to the LV and PBS groups (P<0. 05). Conclusion:rLV-HA-GCN4 can effectively induce cellular and humoral immune response in BALB/c mice against swine H1N1 influenza virus.
8.Evaluation of early efficacy of neoadjuvant chemotherapy in patient with breast cancer based on dynamic contrast-enhanced MRI via comparing with 18F-FDG PET/CT
Yixue CHANG ; Shengbao WEN ; Haihua BAO ; Weixia LI ; Yousen WU
Journal of Practical Radiology 2024;40(2):222-225,269
Objective To investigate the predictive value of early efficacy of neoadjuvant chemotherapy(NAC)in patient with breast cancer via full quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI).Methods Forty patients with breast cancer were selected.The 18 fluorodeoxyglucose positron emission tomography/computed tomography(18F-FDG PET/CT)and DCE-MRI were performed before and after two cycles of NAC.According to the decrease rate of maximum standardized uptake value(ΔSUVmax)of PET/CT before and after two cycles of NAC,all patients were divided into two groups,including good response group(24 cases)(ΔSUVmax>40%)and general response group(16 cases)(ΔSUVmax≤40%).The changes of full quantitative parameters of DCE-MRI between the two groups were observed and analyzed.Results There were statistically significant differences in changes of Ktrans and Kep between the two groups(P<0.05),however,there was no significant difference in the change of Ve between the two groups(P>0.05).There was a significant positive correlation between ΔKtrans and ΔSUVmax(r=0.850,P<0.001).There was a high positive correlation between ΔKtrans and ΔKep(r=0.727,P<0.001).Conclusion The full quantitative parameters of DCE-MRI are helpful to evaluate the early efficacy of NAC in breast cancer,which can reflect the changes of microcirculation in the lesion,further reflect the therapeutic effect of NAC,guide the clinical optimization of treatment plan in time,and achieve accurate evaluation and individualized treatment.
9.Cell type specificity of signaling: view from membrane receptors distribution and their downstream transduction networks.
Ying HE ; Zhonghao YU ; Dongya GE ; Rui WANG-SATTLER ; Hans-Jürgen THIESEN ; Lu XIE ; Yixue LI
Protein & Cell 2012;3(9):701-713
Studies on cell signaling pay more attention to spatial dynamics and how such diverse organization can relate to high order of cellular capabilities. To overview the specificity of cell signaling, we integrated human receptome data with proteome spatial expression profiles to systematically investigate the specificity of receptors and receptor-triggered transduction networks across 62 normal cell types and 14 cancer types. Six percent receptors showed cell-type-specific expression, and 4% signaling networks presented enriched cell-specific proteins induced by the receptors. We introduced a concept of "response context" to annotate the cell-type dependent signaling networks. We found that most cells respond similarly to the same stimulus, as the "response contexts" presented high functional similarity. Despite this, the subtle spatial diversity can be observed from the difference in network architectures. The architecture of the signaling networks in nerve cells displayed less completeness than that in glandular cells, which indicated cellular-context dependent signaling patterns are elaborately spatially organized. Likewise, in cancer cells most signaling networks were generally dysfunctional and less complete than that in normal cells. However, glioma emerged hyper-activated transduction mechanism in malignant state. Receptor ATP6AP2 and TNFRSF21 induced rennin-angiotensin and apoptosis signaling were found likely to explain the glioma-specific mechanism. This work represents an effort to decipher context-specific signaling network from spatial dimension. Our results indicated that although a majority of cells engage general signaling response with subtle differences, the spatial dynamics of cell signaling can not only deepen our insights into different signaling mechanisms, but also help understand cell signaling in disease.
Cell Line
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Databases, Protein
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Gene Expression Profiling
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Humans
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Metabolic Networks and Pathways
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Neoplasms
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metabolism
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pathology
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Proteome
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analysis
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Receptors, Cell Surface
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metabolism
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Receptors, Tumor Necrosis Factor
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metabolism
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Signal Transduction
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Vacuolar Proton-Translocating ATPases
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metabolism
10.Prediction of functional phosphorylation sites by incorporating evolutionary information.
Shen NIU ; Zhen WANG ; Dongya GE ; Guoqing ZHANG ; Yixue LI
Protein & Cell 2012;3(9):675-690
Protein phosphorylation is a ubiquitous protein post-translational modification, which plays an important role in cellular signaling systems underlying various physiological and pathological processes. Current in silico methods mainly focused on the prediction of phosphorylation sites, but rare methods considered whether a phosphorylation site is functional or not. Since functional phosphorylation sites are more valuable for further experimental research and a proportion of phosphorylation sites have no direct functional effects, the prediction of functional phosphorylation sites is quite necessary for this research area. Previous studies have shown that functional phosphorylation sites are more conserved than non-functional phosphorylation sites in evolution. Thus, in our method, we developed a web server by integrating existing phosphorylation site prediction methods, as well as both absolute and relative evolutionary conservation scores to predict the most likely functional phosphorylation sites. Using our method, we predicted the most likely functional sites of the human, rat and mouse proteomes and built a database for the predicted sites. By the analysis of overall prediction results, we demonstrated that protein phosphorylation plays an important role in all the enriched KEGG pathways. By the analysis of protein-specific prediction results, we demonstrated the usefulness of our method for individual protein studies. Our method would help to characterize the most likely functional phosphorylation sites for further studies in this research area.
Animals
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Cyclin-Dependent Kinase Inhibitor p27
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metabolism
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Databases, Protein
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Humans
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Mice
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Phosphorylation
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Proteins
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metabolism
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Rats
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Software
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Tumor Suppressor Protein p53
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metabolism