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Objective To investigate the effects on cell proliferation and invasion of the circular RNA hsa_circ_0067582 in gastric cancer(GC). Methods After hsa_circ_0067582 overexpression (Oe-circ_0067582) plasmid was transfected into AGS and SGC-7901 cells,the cell viability,proliferation,invasion ability,and apoptosis were detected by CCK-8,colony formation and EdU assays,Transwell assay,and flow cytometry,respectively.Western blotting was employed to detect the expression levels of proteins related to the cell apoptosis and epithelial-mesenchymal transition(EMT).The effect of Oe-circ_0067582 on the growth of SGC-7901 cells in nude mice was observed.Bioinformatics tools were used to predict the binding target miRNA of hsa_circ_0067582,and the competing endogenous RNA(ceRNA)regulatory network was established.Finally,functional enrichment was performed to analyze the biological functions of the target genes of the predicted miRNA. Results Compared with the pLO-ciR(empty plasmid)group,the Oe-circ_0067582 group in AGS and SGC-7901 cells attenuated the cell viability(t=7.883,P=0.001;t=5.679,P=0.005),proliferation(t=6.709,P=0.003;t=5.857,P=0.003),and invasion ability(t=7.782,P=0.002;t=6.342,P=0.003)and induced cell apoptosis(t=7.225,P=0.002;t=11.509,P=0.001).Western blotting showed that the Oe-circ_0067582 group in AGS and SGC-7901 cells up-regulated the protein levels of cysteinyl aspartate specific proteinase (Caspase) 3(t=6.863,P=0.002;t=7.024,P=0.001),Caspase 7(t=3.295,P=0.04;t=6.008,P=0.004),Caspase 9(t=4.408,P=0.012;t=6.278,P=0.004),and E-cadherin(t=12.453,P=0.002;t=10.867,P=0.001),while down-regulated those of Vimentin(t=7.242,P=0.002;t=5.694,P=0.004)and N-cadherin(t=6.480,P=0.003;t=7.446,P=0.001).Furthermore,Oe-circ_0067582 significantly inhibited the growth of tumor in the SGC-7901 tumor-bearing nude mice(t=3.526,P=0.017).The prediction based on TargetScan and miRnada suggested that hsa_circ_0067582 can competitively bind to hsa-miR-181b-3p,hsa-miR-337-3p,hsa-miR-421,and hsa-miR-548d-3p.The functional enrichment indicated that the target genes of miRNA were involved in multiple cancer-related biological processes including negative regulation of apoptotic process,gene expression,transcriptional misregulation in cancer,transforming growth factor-β,and p53 signaling pathways. Conclusion Oe-circ_0067582 can inhibit the proliferation and attenuate EMT process to reduce the invasion ability of AGS and SGC-7901 cells,which provides a new target for the treatment of GC.
Subject(s)
Animals , Mice , Cell Proliferation , Gene Expression Regulation, Neoplastic , Mice, Nude , RNA, Circular , Stomach Neoplasms/pathologyABSTRACT
@# Objective: To investigate the mechanism of lncRNA XIST (XIST) on modulating gastric cancer progression via regulating miR-337-3p/HOXC8 axis. Methods: A total of 58 cases of gastric cancer tissues and corresponding para-cancerous tissues resected from March 2013 to January 2018 in Department of General Surgery, Kailuan General Hospital of Tangshan City were collected for this study; in addition, human gastric cancer cell lines (AGS, MGC803, HGC27) and human gastric mucosal GES-1 cells were also collected. qPCR was used to detect the expressions of XIST and miR-337-3p in above mentioned gastric tissues and cell lines. XIST-knockdown vectors, miR-337-3p mimics, miR-337-3p inhibitor and HOXC8-overexpression vectors were transfected into AGS cells. The proliferation and invasion of AGS cells were detected by CCK-8 and Transwell experiments respectively, and the expression levels of HOXC8, E-cadherin, N-cadherin and vimentin were detected by WB. The targeting relationships between XIST, miR337-3p and HOXC8 were verified by dual-luciferase reporter gene assay. Results: XIST was up-regulated in gastric cancer tissues and cell lines (all P<0.01). XIST knockdown significantly inhibited proliferation, invasion and EMT of AGS cells (P<0.05 or P<0.01). Moreover, XIST directly interacted with miR-337-3p and down-regulated its expression, while HOXC8 was the target gene of miR-3373p. Furthermore, XIST knockdown suppressed proliferation, invasion and EMT ofAGS cells through up-regulating the inhibitory effect of miR-337-3p on HOXC8 (P<0.05 or P<0.01). Conclusion: XIST knockdown can suppress the proliferation, invasion and EMT of AGS cells, which may be related with down-regulation of HOXC8 by targeting miR-337-3p.
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@# Objective： ：To study the effect of silencing DKK1 (Dickkopf1) gene on the proliferation, cell cycle and apoptosis of gastric cancer AGS cells and the action mechanism. Methods： ：The DKK1-shRNA vector was constructed and transfected into AGS cells. The stably transfected cell lines were screened. The total protein and RNAof the transfected cells were extracted and the mRNAand protein expressions of DKK1 were detected by qPCR and WB, respectively. The experiment was divided into blank control group (Control), negative control group (shNC) and DKK1 silence group (DKK1-shRNA). CCK8 assay was used to detect the proliferation ofAGS cells of each group cultured for 0, 24, 48, 72, 96, 120 and 144 h, and flow cytometry was used to analyze the cell cycle and apoptosis in each group. The relationship between DKK1 and clinicopathological features of gastric cancer was analyzed after searching HPA database. Results：The gastric cancer AGS cells with stable DKK1 gene knockdown was successfully established, and it was confirmed that the mRNA and proteinexpressions of DKK1 in DKK1-shRNA group decreased by 72% and 47%, respectively, compared to shNC group (all P<0.05). The cell proliferation curve showed that, the cell proliferation in DKKl-shRNAgroup significantly decreased after 72 hour of culture compared with that in control and shNC groups (P<0.05). The cell number of S phase decreased from 32.06% to 25.87%, while the number of G2/M phase increased from 8.49% to 21.26% compared with shNC group (all P<0.05). The number of apoptotic cells also statistically increased from 10.34% to 20.65% (all P<0.05). The data of HPAdatabase showed that DKK1 mRNAlevel in gastric cancer tissues was significantly higher than that in normal tissues, and the high expression of DKK1 mRNAwas negatively correlat ed with the survival rate of gastric cancer patients. Conclusion: : Silencing DKK1 gene can inhibit the proliferation of gastric cancer cells, arrest cells in G2/M phase and promote cell apoptosis. DKK1 plays a pro-carcinogenic effect in gastric cancer.
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@# Objective: To investigate the expression of Formin-2（FMN2）protein in gastric cancer tissues and its correlation to clinicopathological features of gastric cancer patients, as well to explore its effect on the proliferation of gastric adenocarcinoma AGS cells. Methods: 84 cases of gastric adenocarcinoma tissues and corresponding para-cancerous tissues were surgically collected from patients treated in the First Affiliated Hospital of Air Force Military Medical University from September 2015 to September 2017. The expression of FMN2 in gastric adenocarcinoma tissues was detected by immunohistochemical staining and analyzed with RNA-Seq data-sets GEPIA. The relationship between FMN2 protein expression in gastric adenocarcinoma tissues and its clinicopathological features was also explored. MTT assay was used to detect the effect of FMN2 onAGS cell proliferation activity, and Western blotting was used to detect the effect of FMN2 on the expression of apoptosis-related protein caspase-3 in AGS cells. Results: The expression level of FMN2 in gastric adenocarcinoma tissues was significantly lower than that in matched adjacent tissues and the expression level of FMN2 was closely related to the TNM stage and differentiation of gastric adenocarcinoma (all P<0.05). Compared toAGS control group, the proliferation activity of AGS/FMN2 was significantly decreased and the expression of apoptosis-related gene Caspase-3 was markedly increased (all P<0.05). Conclusion: The expression of FMN2 was significantly decreased in gastric adenocarcinoma tissues and its low expression is closely related to the degree of tumor differentiation and clinical TNM stage. Moreover, FMN2 over-expression significantly decreased the proliferation of AGS cells. FMN2 may function as independent risk factor for the prognosis of gastric adenocarcinoma, which may provide new ideas for the treatment of gastric adenocarcinoma.
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Objective To explore the correlation between ATF5 protein expression level and drug sensitivity of gastric cancer AGS cells.Methods We established the high,middle and low ATF5 expression groups by transfecting the AGS cells with ATF5 pcDNA3.1 plasmid,ATF5 siRNA and empty plasmid using the liposome transfection technique.Then we detected the expression of the ATF5 protein of the 3 groups using the Western Blot.The drug sensitivity of AGS cells in 3 groups to paclitaxel and cisplatin was detected using the MTT experiments and plate clone formation experiments then the correlation between ATF5 protein expression level and drug sensitivity of gastric cancer AGS cells was analyzed.Results With the effect of paclitaxel or cisplatin on AGS cells in 3 groups,the surviving fraction and the IC50 of high ATF5 expression group were higher than those of control group,which indicated statistical significance (all P ＜ 0.05);while the surviving fraction and the IC50 of low ATF5 expression group were lower than those of control group (all P ＜ 0.05,P cisplatin =0.00,P paclitaxel =0.002).We found that cell clone formation of AGS cells to paclitaxel and cisplatin was significantly increased after the transfection with ATF5 protein plasmid and decreased after transfection with ATF5 siRNA plasmid (all P ＜ 0.05).Conclusion The expression of ATF5 protein is related to the drug sensitivity of gastric cancer AGS cells that upregulation of ATF5 protein expression can decrease the drug sensitivity of AGS cells to paclitaxel and cisplatin in gastric cancer.
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This study evaluated the anti-Helicobacter and anti-inflammatory effects of Sohamhyungtang (SHHT). The minimum inhibitory concentration (MIC) of SHHT against Helicobacter pylori (H. pylori) was determined by the agar dilution method. Expression of the H. pylori cagA gene in the presence of SHHT was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Inhibition of H. pylori urease by SHHT was determined by the phenol-hypochlorite assay. Antiadhesion activity of SHHT was measured by ureaphenol red reagent. Inhibition of nitric oxide (NO) production in AGS cells was measured with Griess reagent. Inducible nitric oxide synthase (iNOS) and IL-8 mRNA expression in AGS cells which were infected with H. pylori was determined by qRT-PCR. IL-8 level was measured by enzyme-linked immunosorbent assay (ELISA). The MIC of SHHT was 100 µg/mL and the expression of cagA gene was decreased about 25 folds in the presence of SHHT. H. pylori urease was inhibited 90% by SHHT. SHHT inhibited H. pylori adhesion on AGS cell in a concentration dependent manner. mRNA expression of iNOS and IL-8 and the production of NO and IL-8 were significantly decreased in the presence of SHHT. In conclusion, SHHT showed anti-Helicobacter activity and has potent anti-inflammatory effect on H. pylori-induced inflammation in human gastric epithelial AGS cells.
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Humans , Agar , Enzyme-Linked Immunosorbent Assay , Helicobacter pylori , Helicobacter , Inflammation , Interleukin-8 , Methods , Microbial Sensitivity Tests , Nitric Oxide , Nitric Oxide Synthase Type II , Real-Time Polymerase Chain Reaction , RNA, Messenger , UreaseABSTRACT
PURPOSE: The common triple therapy for Helicobacter pylori is challenged by the increasing cases of antibiotic resistant infections, raising the need to explore alternative therapies. Oral administration of egg yolk immunoglobulin Y (IgY) has been previously reported as a means of passive immunization therapy for H. pylori infections. In this work, we investigated the inhibitory effect of IgY on the attachment of H. pylori to AGS cell line. MATERIALS AND METHODS: Recombinant OipA was prepared. Hens were immunized with recombinant protein three times. IgY was purified from egg yolks of immunized hens using polyethylene glycol precipitation method. The inhibitory effect of the specific immunoglobulin was evaluated in AGS cell line infected with H. pylori. RESULTS: The presence of recombinant OipA (30 kD) was confirmed via sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Immunization of hens was confirmed using enzyme-linked immunosorbent assay. The purified IgY from egg yolks were assessed using SDS-PAGE and confirmed by western blot. CONCLUSION: The results showed that IgY-OipA had inhibitory effect on attachment of H. pylori to AGS cell line and may be utilized as a therapeutic or prophylaxis material.
Subject(s)
Administration, Oral , Blotting, Western , Cell Line , Complementary Therapies , Egg Yolk , Electrophoresis, Polyacrylamide Gel , Enzyme-Linked Immunosorbent Assay , Helicobacter pylori , Helicobacter , Immunization , Immunization, Passive , Immunoglobulins , Polyethylene Glycols , Sodium Dodecyl SulfateABSTRACT
We investigated the optimal culture conditions for Cryptosporidium muris in a human stomach adenocarcinoma (AGS) cell line by determining the effects of medium pH and of selected supplements on the development of C. muris. The optimum pH of the culture medium required for the development of C. muris was determined to be 6.6. The number of parasites significantly increased during cultivation for 72 hr (p < 0.05) at this level. On the other hand, numbers decreased linearly after 24 hr of incubation at pH 7.5. When cultured in different concentrations of serum, C. muris in media containing 5% FBS induced 4-7 times more parasites than in 1% or 10% serum. Of the six medium supplements examined, only 1 mM pyruvate enhanced the number of C. muris in vitro. Transmission electron microscopic observation showed the developmental stages of C. muris in the cytoplasm of the cells, not in an extracytoplasmic location. The growth of C. muris in AGS cells provides a means of investigating its biological characteristics and of testing its response to therapeutic agents. However, a more optimized culture system is needed for the recovery of oocysts on a large scale in vitro.
Subject(s)
Animals , Humans , Adenocarcinoma , Cell Line, Tumor , Cryptosporidium/growth & development , Culture Media , Hydrogen-Ion Concentration , Stomach/parasitology , Stomach NeoplasmsABSTRACT
Objective To investigate the effects of Helicobacter priori (H.prlori) strains from the patient with gastric cancer on the expression of DNA mismatch repair (MMR) genes in AGS cells in vitro. Methods AGS cells were co-cultured with ten strains of H.prlori from five patients with gastric cancer and five patients with gastritis respectively.The expressions of DNA MMR genes (hMSH2 and hMLH1) in mRNA and protein levels were determined by RT-PCR and Western blot.The enteropathogenic E.coli served as a bacterial control.Results E.coli and H.priori strains from gastritis have no effects on the expression of hMSH2 and hMLH1 in both protein and mRNA levels on the whole,while all the H.prlori strains from gastric cancer reduced expression levels of hMSH2 and hMLH1.Conclusions There are different effects between H. prlori strains from gastric cancer and those from gastritis on DNA MMR in AGS cell line,indicating that infec- tion of some H.prlori strains might lead to the inhibition of DNA MMR,and that in turns increases the risk of gastric carcinogenesis during chronic H.prlori infection.