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ObjectiveThe aim of this study is to investigate the role of salidroside in regulating the miR-1343-3p/MAP3K6 （mitogen-activated protein kinase kinase kinase 6）/MMP24 （membrane-type matrix metalloproteinase 24） signaling pathway to inhibit gastric cancer cell proliferation and migration. MethodsHuman gastric cancer cells （MGC-803） were divided into several groups based on different salidroside concentrations： a control group （0 μmol/mL）， a low-dose group （6 μmol/mL）， a medium-dose group （12 μmol/mL）， and a high-dose group （24 μmol/mL）. The anti proliferative effects of salidroside on human gastric cancer cells were evaluated by CCK-8 assay. Clonogenic assay was used to examine the effects of salidroside drugs on the clonogenic ability of human gastric cancer cells. Transwell assay was performed to detect the effect of salidroside on the invasive ability of human gastric cancer cells. Cell scratch assay was performed to detect the effect of salidroside on the migration ability of human gastric cancer cells. The miRNA expression profile was analyzed by using RNA-seq in cancer cells for 24 h after salidroside treatment. The differentially expressed miRNAs were clustered and their target genes were predicted. Gene Ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） were used to analyze and predict the functions of these target genes， and the interaction networks were established. Immunocytofluorescence was used to detect the expression of target proteins， and the transcription of candidate genes was detected by q-PCR. ResultsCCK-8 cytotoxicity experiments showed that salidroside inhibited the proliferation of MGC-803 cells （P < 0.01）. Cell cloning experiments showed that salidroside reduced the clonal formation capacity of MGC-803 cells （P < 0.000 1）. Cell invasion experiments showed that salidroside reduced the MGC-803 cell invasion capacity （P < 0.000 1）. Cell scratch experiments showed that salidroside reduced the cell migration capacity （P < 0.000 1）. RNA-seq findings showed that the expression of 44 miRNAs changed significantly after salidroside treatment in cancer cells （P < 0.05）. Bioinformatic analysis showed that there were 1 384 target mRNAs corresponding to the differentially expressed miRNAs， and the expression of the tumor suppressor miR-1343-3p was significantly upregulated after salidroside treatment （P < 0.01），and resulted in down-regulated transcription of MAP3K6 and MMP24 genes which are related to the proliferation and migration of cancer cells （P < 0.05）. Immunofluorescence experiments demonstrated that salidroside reduced protein expression levels in MAP3K6 and MMP24 genes （P < 0.000 1）. q-PCR experiments showed that salidroside reduced the mRNA expression level of MAP3K6 and MMP24 genes （P < 0.000 1）， while miRNA expression in miR-1343-3p gene was upregulated （P < 0.000 1）. ConclusionSalidroside regulates the miRNA-1343-3p/MAP3K6/MMP24 signaling molecules to inhibit proliferation and invasion of gastric cancer cells.
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Objective:To investigate the effects of miR-195 on the migration, invasion and epithelial mesenchymal transition (EMT) of human gastric cancer cell line (HGC-27) and its mechanism.Methods:HGC-27 cells were cultured in vitro and they were randomly divided into control group, miR-195 negative control (NC) group and miR-195 mimics (mimics) group; the expressions of miR-195 and SALL4 mRNA were detected by real-time fluorescence quantitative PCR (RT-qPCR) ; The changes in cell morphology of each group were observed under a microscope; the expressions of SALL4, E-cadherin, N-cadherin and Vimentin in HGC-27 cells were detected by Western blot; MTT method was used to detect the change of HGC-27 cell survival rate; the abilities of migration and invasion in HGC-27 cells were detected by scratch test and invasion test (Transwell) ; and the targeting relationship between miR-195 and SALL4 was confirmed by double Luciferase Report.Results:Compared with those in control group and miR-195 NC group, the miR-195 expression level, apoptosis rate and E-cadherin protein expression level of HGC-27 cells in miR-195 mice group were significantly higher ( P<0.05) , the cell survival rate, scratch healing rate, invasion number, SALL4 mRNA and SALL4, N-cadherin, Vimentin protein expression levels were significantly lower ( P<0.05) , the morphology of HGC-27 cells returned to normal, and the epithelial mesenchymal behavior was significantly reduced; in addition, there was a binding site between miR-195 and SALL4 mRNA 3'UTR region, and compared with that in SALL4-3'UTR-WT + miR-195 NC group, the luciferase activity of SALL4-3'UTR-WT + miR-195 MICs group was lower ( P<0.05) . Conclusion:MiR-195 may inhibit the migration, invasion and epithelieal-mesenchymal transition of human gastric cancer cells by targetingly inhibiting the expression of SALL4.
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OBJECTIVE：To study the effects of limonin on immune function and apo ptosis-related factors expression in MFC gastric cancer bearing model mice. METHODS ：MFC gastric cancer bearing model was established by inoculating MFC gastric cancer cells into the right armpit of mice. After modeling ，model mice were divided into model group ，cyclophosphamide group （positive control ，25 mg/kg）and limonin high-dose ，medium-dose and low-dose groups （100，50 and 25 mg/kg），with 10 mice in each group. Other groups were given relevant medicine intragastrically ，once a day ，for consecutive 14 days，except that model group was given 0.5％ sodium carboxymethyl cellulose intragastrically. Before administration and after last administration ，the body weight of mice was measured ；spleen，thymus and tumor tissue were taken after the last administration to calculate the spleen index，thymus index and tumor inhibition rate. The percentage of CD 4+ and CD 8+ T lymphocytes ，CD4+/CD8+ ratio were detected by flow cytometry. The expression of immune function related indexes （IL-2，IL-10，IFN-γ）in serum were detected by ELISA. RT-PCR and Western blot assay were adopted to detect relative mRNA and protein expression of apoptosis-related factors [cytochrome C （Cyt-C），Bcl-2，Bax] in tumor tissue of mice. RESULTS ：There was no significant difference in body weight among the other groups except that of cyclophosphamide group was decreased significantly ，compared with model group （P＜0.05）. Inhibitory rate of tumor were （58.16 ± 7.07）％ ，（37.09 ± 4.26）％ ，（27.30 ± 3.64）％ ，（15.13 ± 2.95）％ in cyclophosphamide group ，limonin high-dose ，medium-dose and low-dose groups. Compared with model group ，spleen index ， thymus index ，the percentages of CD 4+ and CD 8+T lymphocyte cells ，CD4+/CD8+ ratio，serum levels of IL- 2 and IL- 10，relative mRNA and protein expression of Bcl- 2 in tumor of mice in cyclophosphamide group as well as the expression of IL- 10，relative mRNA and protein expression of Bcl- 2 in limonin groups were decreased significantly （P＜0.05）. The expression of IFN-γ，relative mRNA and protein expression of Cyt-C and Bax of cyclophosphamide group as well as spleen index （except for low-dose group ）， thymus index ， the percentage of CD 4 + and CD 8 + T lymphocytes，CD4+/CD8+ ratio，the expression of IL- 2 and IFN-γ，and relative mRNA and protein expression of Cyt-C and Bax in limonin groups were increased significantly （P＜0.05）. CONCLUSIONS ：Limonin can inhibit tumor growth in MFC gastric cancer bearing model mice ，and the side effects are relatively weak. Its mechanism is related to the improvement of immune function and the induction of apoptosis.
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Objective: The aim of this study is to probe in the inhibitory effects of ginsenoside Rg3 on the expression of hypoxia-induced factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in human gastric cancer cells. Materials and Methods: Human gastric cancer BGC823 cells were divided into the control group and experiment group, and expression levels of HIF-1α and VEGF were detected by immunocytochemistry and Western blot after cells were cultured under hypoxia for different durations. Results: Under hypoxia, expression of HIF-1α and VEGF in human gastric cancer BGC823 cells showed an increasing trend, and that was remarkably lower in experiment group than in the control group after applying Rg3, which was obvious at 12 and 24 h (P < 0.05). Conclusion: Rg3 can inhibit expression of HIF-1α and VEGF in human gastric cancer cells and may influence abdominal implantation metastasis of gastric cancer through inhibiting its expression
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Aim of Study: This study is to investigate the effects of a novel peroxisome proliferator-activated receptor (PPAR) α/γ dual agonist TZD18 on cell growth, apoptosis, caspase activity, mitochondrial membrane potential, cytochrome c release, and apoptotic-related protein expression in MKN-45 cells. Materials and Methods: 3-(4, 5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide assay against various human cancer cell lines was performed to investigate the whether TZD18 could in reduce the proliferation rates of cancer cells. The percentages of apoptotic cells and mitochondrial membrane potential level were determined by flow cytometry. The subcellular localization of cytochrome c was examined by immunofluorescence microscopy. Western blotting assay was performed to reveal the expression of apoptosis-related proteins. Results: The results showed that the administration of TZD18 could inhibit the growth of MKN-45 cells in a dose- and time-dependent manner. In addition, the apoptotic ratio increased sharply along with a significant increase of caspase activities, mitochondrial membrane potential, and cytochrome c release following TZD18 exposure. The expression of Bax and p27kip1 increased significantly, whereas the expression level of Bcl-2 protein was downregulated. Conclusion: These results indicated that the administration of PPAR α/γ agonist TZD18 may inhibit cell growth by inducing the apoptotic process in MKN-45 cells
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Objective: To observe the effect of Weichang'an on the tumor growth and lymph node metastasis, and RUN and FYVE domain-containing protein 3(RUFY3),Zinc finger protein 1(SNAI1),vascular endothelial growth factor(VEGF),epithelial-mesenchymal transition(EMT)-related proteins in nude mice with subcutaneous xenograft tumor human gastric carcinoma MKN45, so as to discuss the mechanism of Weichang'an on MKN45 human gastric metastasis. Method: The nude mice model of human gastric carcinoma MKN45 cells was established and randomly divided into normal saline group (0.5 mL/mouse), Weichang'an granule group (3.54 g·kg-1) and Weichang'an decoction group (35.49 g·kg-1). The tumor weight and volume of axillary lymph nodes in each group were observed. The morphology of lymph nodes in each group was detected by hematoxylin-eosin (HE) staining. The expressions of related proteins were detected by immunohistochemistry, including RUFY3,SNAI1,VEGF,E-cadherin,N-cadherin,Vimentin. Result: Compared with the normal saline group, the tumor weight and volume of axillary lymph node were decreased (PPPConclusion: Both Weichang'an granule and Weichang'an decoction can inhibit the tumor growth and metastasis of axillary lymph nodes, obviously down-regulate the expressions of RUFY3,SNAI1,VEGF,N-cadherin,Vimentin and up-regulate the expression of E-cadherin in human gastric MKN45 subcutaneous transplanted tumor in nude mice. This suggested that Weichang'an may inhibit the tumor metastasis through regulation expressions of RUFY3,SNAI1,VEGF and EMT-related proteins.
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Objective:To define the anti-gastric cancer activity in vitro of petroleum ether fraction of Boehmeria nivea root and reveal the material basis of its efficacy, so as to lay the foundation for the development and utilization of B. nivea root. Method:Methyl thiazolyl tetraolium(MTT) method was used to evaluate the inhibitory rate and time-dose relationship of petroleum ether fraction of B. nivea root with different doses and delivery times on human gastric cancer HGC-27 cells. Flow cytometry was used to detect the change of cell apoptosis and cell cycle after petroleum ether fraction of B. nivea root acted on human gastric cancer HGC-27 cells. GC-MS was used to detect the components of petroleum ether fraction of B. nivea root. Result:Experiment data showed significant cell proliferation inhibition in an obvious time-dose-effect manner, with statistically significant differences (PB. nivea root. The effect of petroleum ether fraction of B. nivea root on human gastric cancer HGC-27 cells could induce apoptosis,which affects the normal changes of cell cycle. The percentage of cells was decreased significantly in G0/G1 phase,and that in S phase was significantly increased. GC-MS was used to identify 26 chemical constituents in petroleum ether of B. nivea root,including sitosterol and stigmasterol. Conclusion:Petroleum ether fraction of B. nivea root is the active anti-gastric cancer part,and its main effective component is sterol compounds. This lays the foundation for the rational application of B. nivea root in clinic and the further research in tis anti-tumor effect.
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@# Objective: To observe the effect of ursolic acid (UA) on autophagy and apoptosis of gastric cancer cell line MGC-803, and to explore the mechanism of UA-induced autophagy of MGC-803 cells based on PI3K/AKT/mTOR signaling pathway. Methods: Human gastric cancer cell line MGC-803 was cultured in vitro and divided into blank control group, UAintervention group and UA+3-MA group. The cell apoptosis in each group was detected by flow cytometry. Cell autophagy was detected by double fluorescence mRFPeGFP-LC3 plasmid transfection method. The mRNA expression levels of LC3B, BAX and Bcl-2 were detected by qPCR. The protein expression levels of PI3K type I, p-AKT, p-mTOR, ULK1, LC3B, BAX and Bcl-2 were detected by WB. Results: Flow cytometry showed that the cell apoptotic rate of UA intervention group was significantly higher than that of blank control group (P<0.05). Compared with UAintervention group, the apoptotic rate in UA+ 3-MAgroup was significantly reduced (P<0.05). The double fluorescence mRFP-eGFP-LC3 plasmid transfection method showed that the green and red fluorescent bright spots in UA intervention group increased significantly compared with the blank control group (P<0.05), and the green and red fluorescent bright spots in UA+3-MA group were significantly reduced compared with UA intervention group (P<0.05). Real-time quantitative PCR and WB method showed that compared with the blank control group, the mRNAand protein expressions of BAX and LC3B, and ULK1 protein were significantly increased in UA intervention group, while the mRNA and protein expressions of Bcl-2, and the protein expressions of PI3K, p-AKT and p-mTOR were significantly decreased in UA intervention group (all P<0.05); Compared with UA intervention group, mRNA and protein expressions of BAX and LC3B were significantly down-regulated and the mRNAand protein expressions of Bcl-2 were significantly up-regulated in UA+3-MA group (all P<0.05), while protein levels of PI3K, p-AKT, p-mTOR and ULK1 were not significantly changed in UA+3-MA group (P>0.05). Conclusion: UA can promote apoptosis of MGC-803 cells via inducing autophagy, which may be related to UA's involvement in regulating the expressions of PI3K/AKT/mTOR signaling pathway-related proteins.
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OBJECTIVE： To study the effects of ivermectin on the migration and invasion of human gastric cancer cell lines BGC-823 and MGC-803 and its mechanism. METHODS： After treated with 0， 2.5， 5， 10， 20， 40 μmol/L ivermectin for 24 h， inhibitory rate of human gastric cancer cell lines BGC-823 and MGC-803 were detected by MTT assay. Effects of 5 μmol/L ivermectin and phosphate buffercontaining 0.67‰ dimethyl sulfoxide （control group） for 24 h on the migration and invasion of` gastric cancer cells BGC-823 and MGC-803 were observed by Transwell chamber invasion assay.Western blot assay was used to detect the protein expression of TGF-β1， TGF-βR， Smad2 and Smad3 in epithelial-mesenchymal transition （EMT） markers E-cadherin， N-cadherin， Vimentin， Snail and EMT transduction pathway TGF-β/smad of BGC-823 and MGC-803 cells after treated with 5， 10 μmol/L ivermectin and phosphate buffercontaining 0.67‰ dimethyl sulfoxide （control group） for 24 h. RESULTS： Ivermectin could inhibit the growth of BGC-823 and MGC-803， inhibitory rate of it was positively correlated with its concentration. Compared with control group， the number of migration and invasion BGC-823 and MGC-803 cells were decreased significantly after treated with 5 μmol/L ivermectin （P＜0.01 or P＜0.001）； the expression of E-cadherin protein was enhanced significantly in BGC-823 and MGC-803 cells after treated with 5 and 10 μmol/L ivermectin （P＜0.05 or P＜0.01 or P＜0.001）； the protein expression of N-cadherin， Vimentin， Snail， TGF-βR， Smad2 and Smad3 were decreased significantly （P＜0.05， P＜0.01 or P＜0.001）； protein expression of TGF-β1 was decreased significantly after treated with 10 μmol/L ivermectin （P＜0.05）. CONCLUSIONS： Ivermectin can significantly inhibit the migration and invasion of gastric cancer cells BGC-823 and MGC-803， and inhibiting the biological activity of EMT by reducing the expression of TGF-β/smad pathway is one of the mechanisms that inhibit the migration and invasion of gastric cancer cells.
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OBJECTIVE： To study the effects of aspirin on the growth and autoghagy of human gastric cancer cells SGC-7901 and BGC-823. METHODS： SGC-7901 and BGC-823 cells were selected as research objects， with phosphate buffer （PBS） as negative control treated for 48 h， MTT assay was used to detect the effects of 1， 2， 4， 6， 8， 10 mmol/L aspirin， 5 mmol/L aspirin alone or combined with 2.5 μmol/L chloroquine， 2.5 μmol/L 3-methyladenine （3-MA） on survival rate of gastric cancer cells. Flow cytometry was used to detect the effects of 2 and 5 mmol/L aspirin， 5 mmol/L aspirin alone or combined with 2.5 μmol/L chloroquine and 2.5 μmol/L 3-MA on the apoptosis rate and cell cycle distribution of gastric cancer cells. Hoechst33258 staining was used to observe the effects of 5 mmol/L aspirin on morphology of gastric cancer cell nucleus； Transwell chamber test was adopted to detect the effects of 5 mmol/L aspirin on the migration of gastric cancer cell. Laser confocal scanning microscopy was used to observe the effects of 5 mmol/L aspirin on autophagy formation in gastric cancer cells. Western blot method was used to detect the effects of 2 and 5 mmol/L aspirin on the protein expression of autophagy markers LC3-Ⅱin gastric cancer cells. RESULTS： Compared with negative control group， aspirin could inhibit the survival rates of SGC-7901 and BGC-823 cells in dose-dependent manner， but had no significant effects on apoptosis rate of SGC-7901 and BGC-823 cells； SGC-7901 and BGC-823 cells were blocked in G1 phase. Compared with aspirin alone group， the survival rates of SGC-7901 and BGC-823 were increased significantly after treated with aspirin+chloroquine and aspirin+3-MA， while the distribution rate of SGC-7901 and BGC-823 cells at G1 phase were decreased significantly， with statistical significance （P＜0.05 or P＜0.01）. Compared with negative control group， there were no obvious DNA fragmentation fragments， apoptotic bodies and fragments of dense bright blue， while the number of migration cells were decreased significantly in SGC-7901 and BGC-823 cells after treated with aspirin （P＜0.001）； the number of autophagosome was increased significantly and the protein expression of LC3-Ⅱ was enhanced significantly （P＜0.05）. CONCLUSIONS： Aspirin can significantly inhibit the growth of SGC-7901 and BGC-823 cells， and arrest cell cycle in G1 phase， the mechanism of which may be associated with the activation of autophagy.
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Objective Based on the previous research that the ethanolic extract from traditional Chinese medicine fructus forsythiae (Lianqiao) can obviously inhibit cancer cells in vitro, the article aimed to investigate the anti-proliferation effects of dammar-24-ene-3β-acetate-20S-ol (DM) extracted from fructus forsythiae on gastric cancer cells and its mechanism.Methods MTT assay was used to assess the anti-proliferation effects of DM on gastric cancer cells including SGC-7901, BGC-823, and MKN-45 in vitro.There were MKN-45 control group and its low dose and high dose groups, BGC-823 control group and its low dose and high dose groups, SGC-7901 control group and its low dose and high dose groups in the experiment.Flow cytometry was used to analyze the cell apoptosis rate.Cellquest software was used to analyze the results and record the ratio of cells at different cycles.DCFH-DA probe was applied to detect the ROS levels of blank control group, docetaxol group and DM group.The reaction system of microtubule assembly test was set with 10?mol/L docetaxol, 50 or 100 μmol/L DM final density and no medicine in blank control group.The readings of UV spectrophotometer were recorded.Microtubule assembly assay and microtubule immunofluorescence staining were applied to investigate the effects of DM on microtubule system.Results The inhibition ratio of 50 μg/L DM on the proliferation three gastric cell lines were all above 80%, with IC50s of MKN-45 11.72±1.35 μg/mL, BGC-823 17.19±0.82 μg/mL, SGC-7901 7.55±0.79 μg/mL.8 days′ low density culturing at 48 hours after 2 μg/mL DM treatment, compared with control group, the number of cell clones significantly reduced without much change in clone size, while 48 hours after 10 μg/mL DM treatment, besides a few clones of BGC-823, there were just several megascopic clones of SGC-7901 and MKN-45.In comparison with apoptotic cell ratio in MKN-45 control group[(21.1±2.5)%], its low dose group and high dose group resulted in significant rise of apoptotic cell ratio[(25.1±1.3)% and (55.2±2.3)%] (P0.05).In comparison with MKN-45 control group, the ratio of cells at S phase decreased in its low dose group[(14.5±2.7)% vs (12.3±3.3)%,P>0.05].In comparison with BGC-823 control group, the ratio of cells at S phase increased in its low dose group[(12.2±5.4)% vs (20.2±2.1)%,P<0.05].In comparison with SGC-7901 control group, the ratio of cells at S phase increased in its low dose group[(21.5±3.8)% vs (31.3±2.6)%,P<0.05].From the detection of intracellular active oxygen after DM treatment, dose-dependent ROS level increased in all three cell lines 48 hours after 10μg/mL and 50μg/mL DM treatment.From the results of microtubule immunofluorescence staining, 48 hours after the treatment of IC50 docetaxol and 10μg/mL DM, the fluorescence signals were in local concentration and disorder.Conclusion Dammar-24-ene-3β-acetate-20S-ol demonstrated anti-proliferation effects due to the apoptosis induced by cell cycle arrest at S phase.
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Objective To investigate the inhibitory effects of medicinal serum of Shenqi Yiliu Formula on cell proliferation of gastric cancer MGC-803 cells;To discuss relevant mechanism. Methods After treated with different concentrations of medicinal serum of Shenqi Yiliu Formula, gastric cancer MGC-803 cells were tested by the following methods: MTT was employed to test the proliferation of gastric cancer MGC-803 cells; Flow cytometry was used to detect cell cycle; qRT-PCR was used to detect the genetic expressions of CDKN1B and CDKN1C;Western blot was employed to test the protein expressions of p27 and p57. Results When 3%, 5%and 10%medicinal serum of Shenqi Yiliu Formula was treated to MGC-803 cells for 24 h, 48 h and 72 h, proliferation of cells decreased significantly (P<0.01), with time- and dosage-dependent relationship. When 3%, 5% and 10% medicinal serum of Shenqi Yiliu Formula was treated to MGC-803 cells for 24 h, cells in G0/G1 increased, decreased in S. qRT-PCR results showed that compared with the blank control group and the negative control group, mRNA expressions of CDKN1B and CDKN1C of MGC-803 cells in medicinal serum all dose group increased significantly (P<0.01). Western blot results showed that compared with the blank control group, protein expressions of p27 and p57 of MGC-803 cells in medicinal serum all dose group increased significantly (P<0.01). Conclusion Medicinal serum of Shenqi Yiliu Formula can inhibit MGC-803 cells proliferation and the mechanism may be through adjusting CDKN1B, CDKN1C mRNA and proteins expression to intervene in the cell cycle.
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AIM:To investigate the effect of all-trans retinoic acid ( ATRA) on the viability of gastric cancer cell SGC-7901 and the sensitivity to radiotherapy .METHODS:MTT assay was used to examine the cell viability .Radio-sensitivity and cell cycle were determined by colony formation assay and flow cytometry , respectively .The mRNA levels of Bax, Bcl-2, survivin and NF-κB in the cells were measured by RT-qPCR.RESULTS: ATRA inhibited the viability of SGC-7901 cells in a concentration-dependent manner .The maximal inhibition was at concentration of 8 μmol/L.Colony formation assay revealed that the combination of ATRA with X-ray treatment significantly reduced the values of D 0 and Dq, and shifted down the fitting survival curve , as compared with radiotherapy alone .Moreover , ATAR markedly decreased the percentage of G2/M phase in the SGC-7901 cells (P<0.05).In addition, following ATRA treatment, the mRNA levels of Bcl-2 and survivin were decreased (P<0.05), whereas the mRNA levels of Bax and NF-κB were increased (P<0.05). CONCLUSION:ATRA enhances the sensitivity of SGC-7901 cells to radiotherapy , inhibits G2/M arrest and regulates the mRNA expression of Bax , Bcl-2, survivin and NF-κB.
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Objective To investigate whether miR?485?3p plays a role in regulation of radiosensitivity of gastric cancer cells by targeting TLR1. Methods Quantitative real?time PCR and Western blot were used to determine the expression of miR?485?3p and TLR1, respectively. The interaction between miR?485?3p and TLR1 was verified by target prediction software ( DIANA, TargetScan, and miRanda) and dual luciferase reporter assay. Gastric cancer MGC803 cells transfected with miR?485?3p mimic or TLR1 siRNA were exposed to irradiation. Apoptosis assay, colony formation assay, and MTT assay were used to evaluate the changes in radiosensitivity of gastric cancer cells. Dual luciferase reporter assay was used to determine the effects of miR?485?3p overexpression and TLR1 silencing on the activity of NF?κB. Western blot was used to study the effects of miR?485?3p overexpression and TLR1 silencing on NF?κB target genes. Results In gastric cancer cells exposed to radiation, the expression of miR?485?3p was downregulated and the expression of TLR1 was upregulated. TLR1 was predicted to be the target of miR?485?3p by target prediction software. Dual luciferase reporter assay further confirmed TLR1 as the direct target of miR?485?3p. miR?485?3p negatively regulated the expression of TLR1. The overexpression of miR?485?3p, as well as TLR1 silencing, increased the apoptosis rate of cells, reduced colony formation and cell proliferation, and enhanced the radiosensitivity of the cells. Both miR?485?3p overexpression and TLR1 silencing reduced the activity of NF?κB and downregulated the expression of multiple NF?κB target genes. Conclusions miR?485?3p enhances the radiosensitivity of gastric cancer cells probably by targeting TLR1 and regulating the NF?κB signaling pathway.
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Objective To investigate the inhibiting effect of interleukin (IL)‐24 combined with targeted attenuated Salmonella typhimurium vector SL7207/pBud‐VP3 on the growth of gastric cancer cells .Methods The co‐expression eukaryotic expression plasmid pBud‐VP3‐IL‐24 was constructed .The plasmid pBud‐VP3‐IL‐24 was transformed into attenuated Salmonella typhimurium SL7207 by using the high voltage electroporation for constructing the SL 7207/pBud‐VP3‐IL‐24 strain .The mouse gastric cancer transplantation tumor model was established and randomly divided into the normal saline control group ,SL7207/pBud group , SL7207/pBud‐VP3 group and SL7207/pBud‐VP3‐IL‐24 group .The tumor‐bearing mice were fed by oral administration of bacterial strain .The tumor volume was measured and the tumor inhibition rate was calculated .The expression of IL‐24 was detected by Western blotting .The levels of IFN‐γ,IL‐6 and TNF‐αin tumor tissue were detected by using RT‐PCR .The expression of Caspase‐3 and VEGF were detected by using immunohistochemistry .Results The plasmids attenuated Salmonella typhimurium vector carrying the gene IL‐24 was successfully constructed .The IL‐24 protein expression was detected in gastric cancer tissue after 14 d treatment .The tumor volume after 28 d treatment in the SL7207/pBud‐VP3‐IL‐24 group was reduced compared with the other groups ,moreover the tumor growth was significantly inhibited ,and the differences were statistically significant (P<0 .05) .RT‐PCR and immunohistochemistry results showed that IL‐24 combined with SL7207/bBud‐VP3 could significantly increase the expression levels of immune factor IL‐6 ,IFN‐γ and TNF‐αin tumor tissue ,.in addition ,up‐regulated the expression of Caspase‐3 and down‐regulated the VEGF expression(P<0 .05) .Conclu‐sion IL‐24 combined with SL7207/pBud‐VP3 can synergically play the inhibitory effect on the growth of gastric cancer cells ,its mecha‐nism is related with the tumor apoptosis promotion ,tumor vessel inhibition and immune regulation .
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Objective To study the cell proliferative effects of fungal immunomodulatory proteins from Ganoderma spp . on 26 gastric cancer cell lines in vitro .Method 26 human gastric cancer cell lines were treated with FIPs by MTS assay .The average optical density (OD) in 490 nm and inhibition rate (GI50 )was counted by Universal Microplate Spectrophotometer . Results Three FIPs showed similar profiling in 26 human gastric cancer cell lines after 72 h treatment in cell proliferation as-say ,which except for NUGC-4 and OCUM-1 did not showed obvious anti-proliferative effect ,the other 24 human gastric cell lines showed some anti-proliferative effects ,especially for 7 cell lines(NUGC-3 ,GTL-16 ,HGC-27 ,IM95m ,SNU-638 ,SNU-216 and SNU-5) showing strong potency ,with their GI50 less than 50 μg/ml .Conclusion FIPs showed strong anti-prolifera-tive effects in some human gastric cancer cell lines in vitro ,which had potential to be further developed as anti-gastric cancer drugs .
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Objective To explore the role of chromokinesin KIF4A in gastric cancer cell invasion using gastric cancer cells SGC-7901 and chromokinesin KIF4A deficient gastric cancer cells (SGC-shKIF4A).Methods Expression levels of KIF4A in controlling gastric cancer cells (SGC-shNC) and SGC-shKIF4A cells were determined by Western Blot.Invasion of gastric cancer cells were assessed using Transwell invasion assay and the number of cells passing through the matrigel was counted.Changing numbers of cortactin in SGC-7901,SGC-shNC,and SGC-shKIF4A cells were analyzed by immunofluorescence staining.Results Compared to the SGC-shNC cells,invasion ability of SGC-shKIF4A cells was increased.Compared to other cells,the numbers of cortactin in SGC-shKlF4A cells was also increased suggesting invadopodia in these cells was increased(P＜0.01).Conclusions Chromokinesin KIF4A acts as a tumor suppressor by inhibiting gastric cancer cells invasion and the results provides strong evidences for KIF4A serving as one of potent targets for gastric cancer prognostics and treatment in clinic.
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Aim To investigate the effects of diallyl di-sulfide( DADS) on G2/M arrest in Chk1/MGC803 and Chk2/MGC803 cells so as to establish stable human gastric cancer MGC803 cells with overexpression of Chk1/2 gene. Methods The colony formation, flow cytometry, RT-PCR and Western blot were used to de-tect the proliferation, cell cycle, and expression of Chk1/2 mRNA and protein, p-Chk1/2, CDC25C and cyclinB1, respectively. Results The colony formation showed that the colony forming efficiency in Chk1/MGC803 and Chk2/MGC803 cells treated by 30 mg· L-1 DADS was lower than in control group and vector group ( P <0. 05 ) . Flow cytometry demonstrated that 41. 3%, 57. 4%, 68. 9% and 42. 9% of G2/M cells in Chk1/MGC803 were increased than in MGC803 and Chk2/MGC803 , respectively after treated by DADS in 12,24, 36 and 48 h(P <0. 05). At the same time, RT-PCR disclosed that expression of Chk1 and Chk2 mRNA had no marked change. Western blot showed that total proteins of Chk1 and Chk2 and p-Chk2 had invisible change, but expression of p-Chk1 was up-reg-ulated, and CDC25C and cyclinB1 were down-regula-ted time-dependently in Chk1/MGC803 cells ( P <0. 05 ) . Conclusion DADS arrests MGC803 cells at G2/M by increasing p-Chk1 expression to cause down-regulation of CDC25C and cyclinB1 simultaneously.
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Objective:To investigate the mechanism of endoplasmic reticulum (ER) stress-induced chemoresistance to cisplatin in gastric cancer cells. Methods:ER stress models were established in both BGC823 and SGC7901 gastric cancer cells. The expression of GRP78, an ER stress marker, was examined by Western blot analysis. Moreover, whether ER stress can decrease the sensitivity of gastric cancer cells to cisplatin and activate P38 was explored by flow cytometry and Western blot analysis, respectively. Whether ER stress-induced chemoresistance to cisplatin can be abrogated by blocking P38 activity in gastric cancer was also elucidated using flow cytometry. Results:GRP78 protein expression markedly increased after treating BGC823 and SGC7901 gastric cancer cells with tunica-mycin (TM) or thapsigargin (TG) for 8, 16, and 24 h (P0.05). Both P38 inhibitors, either SB203580 or PD169316, can inhibit the activation of P38. The inhibition of P38 activity can overcome ER stress-induced chemoresistance to cisplatin in gastric cancer cells (P<0.05). Con-clusion:ER stress can trigger the chemoresistance to cisplatin by activating P38 in gastric cancer cells.
ABSTRACT
Objective To explore effect of isoorientin on gastric cancer cell autophagy.Methods Isoorientin and autophagy activator and effect of inhibitors on proliferation of human gastric cancer cell line SGC-7901 by MTT assay.Cell apoptosis was detected by flow cytometry.Production of autophagy lysosomal in gastric cancer SGC-7901 cells was obseroved by AO and MDC staining.Characteristic expression of autophagy protein was analysed by Western blot.Results MTT assay indicated that isoorientin could inhibit gastric cancer cell growth, RAP has the same effects, but 3-MA inhibition of apoptosis.Flow cytometry was used to detect the apoptosis rate of isoorientin and RAP could promote cell apoptosis , while 3-MA had the opposite effect.In AO staining, the red light appeared in the cells, and the green fluorescence appeared in the cells of MDC staining, which showed that there was an autophagy in the cells.Western blot test found the isoorientin was cell autophagy specific protein LC-3II, Beclin-1 expression increased, 3-MA suppressed the expression of the two proteins, and RAP had the opposite effect.Conclusion Isoorientin could induce apoptosis in gastric cancer SGC-7901 cells, autophagy is involved in the process of death.