Epigallocatechin Gallate Enhances Inhibition Effect of DDP on the Proliferation of Gastric Cancer BGC-823 Cells by Regulating p19Arf-p53-p21Cip1 Signaling Pathway.

OBJECTIVE: To indicate the effect of Epigallocatechin gallate (EGCG) and Cisplatin (DDP) on proliferation of gastric cancer BGC-823 cells and the relative underlying mechanism. METHODS: Cultured BGC-823 cells were treated by 5 µg/mL DDP, 25 µg/mL EGCG and combined 5 µg/mL DDP with 25 µg/mL EGCG, a blank group was used as control. Cell morphology was observed by 4',6-diamidino-2-phenylindole (DAPI) staining. The ability of cell proliferation was detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)assay. The cell cloning rate was determined by colony formation assay. The ability of cell migration was detected by cell scratch test. The cell cycle distributions and apoptosis were analyzed by flow cytometry, The expression of p19Arf, p53, p21Cip1 mRNA was determined by RT-qPCR. The protein levels of p19Arf, p53, p21Cip1 were measured by Western blot. RESULTS: Compared with DDP or EGCG treatment alone, EGCG combined with DDP treatment significantly caused nuclear shrinkage, reduced the proliferation rate, the ability of cell clone and migration. EGCG combined with DDP treatment caused cell cycle arrest in G1 phase in BGC-823 cells, increase of apoptosis (21.3%) vs EGCG (7.25%) and DDP (3.86%) single-use group (p <0.01), up-regulated gene and protein expressions of p19Arf, p53, p21Cip1 (p <0.01). CONCLUSION: EGCG can enhance the effect of DDP on inhibiting BGC-823 cell proliferation and inducing apoptosis via activating the p19Arf-p53-p21Cip1 signaling pathway.

Involvement of mTOR/Survivin signaling pathway in TUA(2ß, 3ß, 23-trihydroxy-urs-12-ene-28-olic acid)-induced apoptosis in human gastric cancer cell line BGC823 cells.

ETHNO-PHARMACOLOGICAL RELEVANCE: A natural ursolic compound, 2ß,3ß,23-trihydroxy-urs-12-ene-28-olic acid (TUA) was isolated from the root of Actinidiafulvicoma Hance. (A.fulvicoma Radix), which is used as a traditional hebal medicine to cure innominate inflammation of unknown origin of the digestive tract in the She nationality. AIM OF THE STUDY: The aim of present study was to investigate the effects of TUA on gastric cancer and to clarify the potential mechanisms in human gastric cancer cell line BGC823 cells in vitro and in vivo. MATERIALS AND METHODS: Cell proliferation, apoptosis, cell cycle, autophagy were all measured by MTS assay, flow cytometry following exposure to TUA. The mRNA expressions of PI3K, AKT, mTOR, P70S6K, Survivin and the protein expressions of p-PI3K, p-AKT, p-mTOR, p-P70S6K, Survivin were determined by qRT-PCR and Western blotting analysis, respectively. In vivo antitumor activity of TUA was assessed in a xenograft model. RESULTS: In vitro studies showed that TUA significantly suppressed the viability of BGC823 cells in a concentration- and time-dependent manner but not GES-1 non-tumorigenic human gastric epithelial cells. TUA also significantly increased the apoptosis rate and the sub G2 population by cell cycle analysis in a concentration dependent manner. Exposure to TUA decreased PI3K, AKT, mTOR, P70S6K, Survivin mRNA, inhibited the phosphorylation of major receptors involved in autophagy and apoptosis, such as PI3K, AKT, mTOR and P70S6K, while reduced the expression of Survivin in BGC cells. In vivo studies showed that TUA decreased tumor volume and tumor weight and also down regulated the autophagy-related proteins expression. CONCLUSIONS: TUA occupies underlying antitumor effects, the potential mechanisms may involve the suppression of mTOR/Survivin pathways connected to autophagy and the activation of apoptotic pathways in gastric cancer cells.

[Effects of miR-141-3p on proliferation, migration and NF-κB signaling pathways in gastric cancer cells].

Objective: To investigate the effects of miR-141-3p on proliferation and migration of gastric cancer cells and nuclear factor-κB (NF-κB) signaling pathway. Methods: Human gastric cancer cell line BGC-823 was cultured, and miR-141-3p mimetic (miR-141-3p mimics) was transfected into BGC-823 cells by lipofection. The miR-141-3p overexpressed BGC was constructed. Real-time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to detect the transfection effect. The proliferation of BGC-823 cells was determined by 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Transwell assay was used to detect the effect of miR-141-3p on BGC-823 cell migration. The expressions of NF-κB p65, p-IKK-α and p-IKB-α protein in NF-κB signaling pathway were detected by western blot. Results: Compared with the control group and the negative control group, the expression level of miR-141-3p in BGC-823 cells of the miR-141-3p group was (2.39±0.27), which was higher than (1.00±0.09) of the control group and (1.01±0.10) of the negative control group (P<0.05). The number of migrating cells in the miR-141-3p group was (47.64±5.65), which was lower than (106.22±12.14) in the control group and (110.40±12.26) in the negative control group (P<0.05). The expression levels of NF-κB p65, p-IKK-α and p-IKB-α protein in BGC-823 cells were down-regulated (P<0.05). Conclusion: MiR-141-3p can inhibit the proliferation and migration of human gastric cancer BGC-823 cells, which may be related to the inhibition of NF-κB signaling pathway activation.

Germacrone exerts anti-cancer effects on gastric cancer through induction of cell cycle arrest and promotion of apoptosis.

BACKGROUND: Germacrone is one of the natural bioactive compounds found in Rhizoma curcuma essential oils. In this study, the potential anti-cancer effect of germacrone in gastric cancer cell line BGC823 was investigated. METHODS: The cell viability and proliferative activity were assessed, and cell cycle analysis was also performed. Hoechst 33258 and Annexin V/PI double staining was used for detection of cell apoptosis. Protein profiles of cell cycle-related and apoptosis-related proteins were assessed. RESULTS: MTT assay revealed that germacrone had marked cytotoxicity on BGC823 cells. Germacrone induced cell cycle arrest in the G2/M phase via remarkably decreased expression levels of cyclin B1, cdc 2 and cdc 25c. In addition, the treatment with germacrone induced caspase-3 activity and PARP cleavage. These findings demonstrated the effects of germacrone on inhibiting cell proliferation through induction of G2/M phase cell cycle arrest and promotion of cell apoptosis. It also indicated that germacrone functioned through modulations of cell cycle-associated protein expression and mitochondria-mediated apoptosis. CONCLUSION: These findings will be valuable as the molecular basis for the germacrone-mediated anti-cancer effect against gastric cancer.

Study on Preparation and in vitro Anticancer Activity of PFV-modified Paclitaxel/artesunate Co-loaded Targeting Micelles / 中国药房

OBJECTIVE：To prepare cell penetrating peptide PFV-modified paclitaxel （PTX）/artesunate（ART）co-loaded targeting micelles ，and to investigate in vitro anti-tumor activity. METHODS ：According to optimal technology ，PFV-modified PTX/ ART co-loaded targeting micelles were prepared by membrane hydration method ，and were characterized. Using blank micelle as blank control ，sulforhodamine B （SRB）method was used to evaluate the toxicity of PTX micelles ，ART micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles to human gastric cancer BGC- 823 cells. The coumarin was used as fluorescent probe replacing PTX to prepare corresponding micelles. Then ，the uptake of BGC- 823 cells to corresponding micelles and targeting effect were observed and determined by flow cytometry and fluorescence microscope. The effects of PTX micelles ， ART micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles on the invasion of BGC- 823 cells were investigated by Transwell chamber method. RESULTS ：Average particle size of PFV-modified PTX/ART co-loaded targeting micelles was （51.30±3.95）nm；PDI was 0.19±0.01，and Zeta potential was （0.21±0.02）mV. The encapsulation efficiency of PTX and ART were higher than 90％. The shape of micelles were spherical. The blank micelles had no obvious toxicity to BGC-823 cells. The IC 50 value of PTX micelles ，PTX/ART micelles and PFV-modified PTX/ART co-loaded targeting micelles to BGC-823 cells were （3.09±0.22），（1.93±0.24），（1.11±0.15）μmol/L，respectively. The distribution amount of different micelles in BGC- 823 cell nucleus in the descending order were PFV-modified coumarin/ART micelles ＞coumarin/ART micelles ＞coumarin micelles＞blank control. The order of inhibitory effect was PFV-modified PTX/ART co-loaded targeting micelles ＞PTX/ART micelles＞ART micelles ＞PTX micelles ＞blank control. CONCLUSIONS： Prepared PFV-modified PTX/ART No.81874347） co-loaded targeting micelles are in line with the quality of 1915286446@qq.com Chinese Pharmacopoeia . It shows strong cytotoxicity to BGC-823 cells，can improve the drug targeting and the cell uptake，and inhibit the inv asion and metastasis of BGC- 823 cells.

MicroRNA-150-5p and SRC kinase signaling inhibitor 1 involvement in the pathological development of gastric cancer.

The current study aimed to assess the regulatory mechanism of microRNA-150-5p (miR-150-5p) in the pathogenesis of gastric cancer. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to verify the expression of miR-150-5p in gastric cancer tissues and cell lines, which was revealed to be highly expressed in each. In addition, the expression of miR-150-5p was associated with advanced gastric cancer and lymph node metastasis. The current study then hypothesized that SRC kinase signaling inhibitor 1 (SRCIN1) was the target gene of miR-150-5p, a theory that was confirmed via a dual luciferase reporter gene assay. RT-qPCR and western blotting were then performed to verify the expression of SRCIN1 in gastric cancer tissues and cell lines. The results demonstrated that SRCIN1 was lowly expressed in gastric cancer tissues and cells. To assess the effect of miR-150-5p on gastric cancer cells, experiments were conducted with BGC-823 cells transfected with a miR-150-5p inhibitor or a miR-150-5p inhibitor+SRCIN1-small interfering (si)RNA respectively. A cell counting kit-8 assay and flow cytometry were also used to assess cell viability and apoptosis, respectively. Western blotting and RT-qPCR were further used to measure the expression of specific markers of epithelial mesenchymal transition (EMT), including epithelial cell markers (E-cadherin and zona occluding-1) and interstitial cell markers (vimentin, N-cadherin and ß-catenin). The results revealed that the miR-150-5p inhibitor attenuated cell viability, induced apoptosis, decreased the expression of interstitial cell markers and increased epithelial cell marker expression. However, all effects of the miR-150-5p inhibitor were reversed following SRCIN1-siRNA treatment. In summary, the current study indicated that the miR-150-5p inhibitor attenuated cell viability, induced apoptosis and inhibited gastric cancer cell EMT by targeting SRCIN1.

Alantolactone induces gastric cancer BGC-823 cell apoptosis by regulating reactive oxygen species generation and the AKT signaling pathway.

Alantolactone (ALT), a natural sesquiterpene lactone, has been suggested to exert anti-cancer activities in various cancer cell lines. However, the effects and mechanisms of action of ALT in human gastric cancer remains to be elucidated. In the present study, the effects of ALT on BGC-823 cells were examined and the underlying molecular mechanisms associated with these effects were investigated. Cell viability was detected by using an MTT assay. Cell cycle, cell apoptosis and the level of reactive oxygen species (ROS) were assessed by flow cytometry, and the expression levels of proteins of interest were analyzed by western blot assay. The results demonstrated that ALT triggered apoptosis and induced G0/G1 phase arrest in a dose-dependent manner. Furthermore, the expression level of the anti-apoptosis protein Bcl-2 was downregulated, and expression of the pro-apoptosis proteins Bax and cleaved PARP were significantly upregulated. The cell cycle-associated proteins cyclin-dependent kinase inhibitor 1 and cyclin-dependent kinase inhibitor 1B were also increased, while cyclin D1 was deceased. In addition, ALT induced apoptosis via the inhibition of RAC-alpha serine/threonine-protein kinase (AKT) signaling and ROS generation, which was effectively inhibited by the ROS scavenger, N-acetyl cysteine. Therefore, the results from the present study indicated that the ROS-mediated inhibition of the AKT signaling pathway serves an important role in ALT-induced apoptosis in BGC-823 cells. In conclusion, the results demonstrated that ALT exerted significant anti-cancer effects against gastric cancer cells in vitro.

Effects of microspherule protein 1 on invasion and migration of gastric cancer cells and their mechanisms / 吉林大学学报(医学版)

Objective: To investigate the effects of overexpression of microspherule protein 1 (MCRS1) in the gastric cancer cells on the invasion and migration of gastric cancer cells, and to elucidate their possible mechanisms. Methods: The gastric cancer BGC-823 cells, SGC-7901 cells and the normal gastric mucosal epithelial GES-1 cells were cultivated. Western blotting method was used to detect the expressions of MCRS1 in three kinds of cells. The result showed that MCRS1 protein had the lowest expression in the BGC-823 cells, so the gastric cancer BGC-823 cells were selected for next experiments. The recombinant plasmid of MCRS1 was constructed, and the gastric cancer BGC-823 cells in the logarithmic growth phase were selected. Blank group, empty vector transfection group and MCRS1 transfection group were established, and the plasmid was transfected into the BGC-823 cells using Lipo3000. The expression levels of epithelial cadherin (E-cadherin) protein, neuronal cadherin (N-cadherin) protein and Snail protein were detected by Western blotting method. The cell scratch assay and Transwell assay were used to detect the migration and invasion of gastric cancer BGC-823 cells. Results: Compared with the normal gastric epithelial GES-1 cells, the expression level of MCRS1 protein in the gastric cancer BGC-823 cells was decreased (P < 0 . 01), but the expression level of MCRS1 protein in the SGC-7901 cells was increased (P < 0 . 01). The PCR identification and sequencing analysis showed that the MCRS1 recombinant plasmid was successfully constructed. Compared with blank group and empty vector transfection group, the expression levels of MCRS1 protein and E-cadherin protein in MCRS1 transfection group were increased (P

RPS15a Silencing Suppresses Cell Proliferation and Migration of Gastric Cancer.

PURPOSE: Information on the possible role of the ribosomal protein S15a (RPS15a) in gastric cancer is scarce. The aim of this study was to evaluate the impact of RPS15a gene expression on the growth and cell cycle of gastric cancer cells in vitro and in vivo. MATERIALS AND METHODS: RPS15a mRNA expression was examined in cancer tissues and their corresponding adjacent normal tissues of 40 gastric adenocarcinoma patients. Next, RPS15a was knocked down using a lentivirus-mediated RNA interference (short hairpin RNA) system in the gastric cancer cell line BGC823. The effect of RPS15a knockdown was examined using CCK-8 assay, cell scratch test, colony formation assay, and flow cytometry. Finally, in nude mice, a tumorigenicity test was performed, and the tumor volume and weight were measured. RESULTS: RPS15a expression in tumor tissue was significantly greater than that in the adjacent normal tissue of gastric cancer patients. After RPS15a silencing, the BGC823 cell proliferation rate decreased significantly; most cells were arrested in the G0/G1 phase, cell growth was inhibited, and the migration rate was decreased. Colony formation assay showed that the number and size of clones in the RPS15a-silenced cells were fewer and smaller, compared to control cells. The nude mouse tumorigenicity test showed that RPS15a silencing had an inhibitory effect on tumor volume and mice weight. CONCLUSION: The present study found RPS15a expression to be higher in gastric tumors and its silencing in gastric cancer cells to inhibit the proliferation, growth, and migration thereof. Accordingly, RPS15a may be considered as a potential therapeutic target in gastric cancer.

Inhibitory effects of CP on the growth of human gastric adenocarcinoma BGC-823 tumours in nude mice.

Objective To investigate the potential antitumour effects of [2-(6-amino-purine-9-yl)-1-hydroxy-phosphine acyl ethyl] phosphonic acid (CP) against gastric adenocarcinoma. Methods Human BGC-823 xenotransplants were established in nude mice. Animals were randomly divided into control and CP groups, which were administered NaHCO3 vehicle alone or CP dissolved in NaHCO3 (200 µg/kg body weight) daily, respectively. Tumour volume was measured weekly for 6 weeks. Resected tumours were assayed for proliferative activity with anti-Ki-67 or anti-proliferating cell nuclear antigen (PCNA) antibodies. Cell apoptosis was examined using terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) assays and with caspase-3 immunostaining. Proteins were measured by Western blotting. Results There was a significant reduction in tumour volume and a reduced percentage of Ki-67-positive or PCNA-positive cells in the CP group compared with the control group. The percentage of TUNEL-positive or caspase 3-positive cells significantly increased following CP treatment compared with the control group. Tumours from the CP group had higher levels of phosphorylated-extracellular signal-regulated kinase (p-ERK) and phosphorylated-AKT (p-AKT) compared with control tumours. Conclusion CP treatment inhibited tumour growth and induced tumour cell apoptosis in a nude mouse model of BGC-823 gastric adenocarcinoma. Activation of the AKT and ERK signalling pathways may mediate this antitumour activity.

Inhibition of Wulong Xiaozheng Pill on migration and invasion of gastric cancer BGC-823 cells and its mechanism / 中草药

Objective To investigate the effect of Wulong Xiaozheng Pill (WXP) on the migration and invasion of human gastric cancer cell-line BGC-823 and its mechanism. Methods WXP, IGF-1, and LY294002 were added on BGC-823 cells. Then the inhibitory effect of WXP was detected by MTT assay. Transwell assay was performed to determine the migration and invasion capacity of on BGC-823 cells. Expressions of VEGF, MMP-2, and MMP-9 were detected by ELISA, while the expressions of related proteins and mRNA in PI3K/NF-κB signaling pathway were detected by Western blotting and RT-PCR. Results WXP can inhibit the proliferation, adhesion, invasion, and migration of BGC-823 cells. In addition, WXP inhibited the expression of VEGF, MMP-2 and MMP-9 protein in BGC-823 cells. WXP significantly inhibited the expression of p-PI3K, p-Akt, p-IKK-a, and p-NF-κB p65Ser 276 proteins, PI3K, Akt, IKKa, and NF-κB mRNA, which showed a time-dependent and dose-dependent manner. Conclusion WXP inhibit the capacity, migration and invasion of BGC-823 cells by blocking PI3K/NF-κB signaling pathway.

Quercetin enhances 5-fluorouracil-induced apoptosis in gastric cancer by down-regulating c-Jun expression / 中国病理生理杂志

AIM:To investigate the enhancing effect of quercetin on the 5-fluorouracil-induced apoptosis in gastric cancer.METHODS: MTT assay was conducted to evaluate the effect of quercetin on the 5-fluorouracil-induced death of gastric cancer cell line BGC-823.Co-immunoprecipitation and Western blot analysis were performed to detect the expression of c-Jun and Bcl-xL,phosphorylation of c-Jun,activation of caspase-9 and caspase-3,and release of cytochrome C in BGC-823 cells treated with quercetin and 5-fluorouracil.The apoptosis of BGC-823 cells treated with quercetin and 5-fluorouracil was analyzed by flow cytometry.RESULTS: Adjuvant therapy of quercetin significantly enhanced the 5-fluorouracil-induced death of BGC-823 cells.Meanwhile, quercetin decreased the half maximal inhibitory concentration (IC50)of 5-fluorouracil to BGC-823 cells.Quercetin treatment significantly inhibited the expression of c-Jun,and inhibited the 5-fluorouracil-induced phosphorylation of c-Jun and the interaction between c-Jun and activating transcription factor 2 (ATF2).Subsequently,quercetin inhibited the up-regulation of Bcl-xL induced by 5-fluorouracil in the BGC-823 cells. However,transfection with c-Jun plasmid abolished the promoting effect of quercetin on 5-fluorouracil-induced cell death. In addition, quercetin promoted 5-fluorouracil-induced release of cytochrome C from mitochondria and caspase-dependent apoptosis in BGC-823 cells.CONCLUSION:Quercetin treatment enhances 5-fluorouracil-induced mitochondrial apoptosis in BGC-823 cells through c-Jun/ATF2/Bcl-xL pathway.

RPS15a Silencing Suppresses Cell Proliferation and Migration of Gastric Cancer

PURPOSE: Information on the possible role of the ribosomal protein S15a (RPS15a) in gastric cancer is scarce. The aim of this study was to evaluate the impact of RPS15a gene expression on the growth and cell cycle of gastric cancer cells in vitro and in vivo. MATERIALS AND METHODS: RPS15a mRNA expression was examined in cancer tissues and their corresponding adjacent normal tissues of 40 gastric adenocarcinoma patients. Next, RPS15a was knocked down using a lentivirus-mediated RNA interference (short hairpin RNA) system in the gastric cancer cell line BGC823. The effect of RPS15a knockdown was examined using CCK-8 assay, cell scratch test, colony formation assay, and flow cytometry. Finally, in nude mice, a tumorigenicity test was performed, and the tumor volume and weight were measured. RESULTS: RPS15a expression in tumor tissue was significantly greater than that in the adjacent normal tissue of gastric cancer patients. After RPS15a silencing, the BGC823 cell proliferation rate decreased significantly; most cells were arrested in the G0/G1 phase, cell growth was inhibited, and the migration rate was decreased. Colony formation assay showed that the number and size of clones in the RPS15a-silenced cells were fewer and smaller, compared to control cells. The nude mouse tumorigenicity test showed that RPS15a silencing had an inhibitory effect on tumor volume and mice weight. CONCLUSION: The present study found RPS15a expression to be higher in gastric tumors and its silencing in gastric cancer cells to inhibit the proliferation, growth, and migration thereof. Accordingly, RPS15a may be considered as a potential therapeutic target in gastric cancer.

CRA(Crosolic Acid) isolated from Actinidia valvata Dunn.Radix induces apoptosis of human gastric cancer cell line BGC823 in vitro via down-regulation of the NF-κB pathway.

A natural ursolic compound, 2α,3ß-dihydroxy-urs-12-en-28-oic acid (corosolic acid, CRA) was isolated from the root of Actinidia valvata Dunn. (A. valvata Radix). Since a large number of triterpenoid compound has marked anticancer effects toward various types of cancer cell lines in vitro, this study was carried out to investigate the anticancer effect of CRA in human gastric cancer cell line BGC823 cells and the underlying apoptotic mechanism of CRA was examined in BGC823 cell lines. The results showed that CRA significantly suppressed the viability of BGC823 cells in a concentration- and time-dependent manner. CRA also significantly increased the sub G1 population by cell cycle analysis in a concentration dependent manner. Exposure to CRA decreased p65, bcl-2, Fas, smac mRNA and protein expression, and increased IκBα, bax, survivin mRNA and protein expression. Results of immunofluorescence staining and EMSA further indicated CRA induced apoptosis by inhibiting nuclear translocation of nuclear factor NF-κB subunit p65. Consistently overall, our findings suggest that CRA induces apoptosis via inhibition of NF-κB (p65) expression level and activation of IκBα in BGC cells as a potent anticancer candidate for gastric cancer treatment.

Inhibition of annonaceous acetogenins on cell activities of human gastric cancer cells in vitro / 中草药

Objective To study the effect of annonaceous acetogenins (ACGs) on human gastric cancer cells in vitro. Methods After ACGs were administered to gastric cancer cells in vitro, the cell viability, cell adhesion ability and cell migration ability were assessed by MTT assay, adhesion assay and wound-healing assay, respectively. Results ACGs inhibited the cell viability, adhesion ability and migration ability in a dose-dependent manner in gastric cancer cells. Conclusion ACGs could inhibit cell activities of human gastric cancer cells in viro, and will be developed as a promising anticancer candidate and used in gastric cancer.

Dihydroartemisinin enhances antitumor effect of 5-fluorouracil against gastric cancer by down-regulating SIRT1 expression / 中国病理生理杂志

AIM:To investigate the effect of dihydroartemisinin ( DHA) adjuvant treatment on enhancing the antitumor effect of 5-fluorouracil (5-FU) against gastric cancer .METHODS:The gastric cancer BGC-823 cells were di-vided into control group , DHA group, 5-FU group, 5-FU+DHA group and 5-FU+DHA+SIRT1 plasmid group.The via-bility of BGC-823 cells treated with DHA and 5-FU was measured by MTT assay .The expression of SIRT1 and NADPH ox-idase, activation of caspase-9 and caspase-3, and phosphorylation of ASK1 and JNK in the BGC-823 cells treated with DHA and 5-FU were determined by Western blot .The production of ROS and the apoptosis of the BGC-823 cells treated with DHA and 5-FU were analyzed by flow cytometry .RESULTS:Dihydroartemisinin significantly inhibited the expression of SIRT1 and increased NADPH oxidase protein level (P<0.05).DHA increased the sensitivity of BGC-823 cells to 5-FU, thus decreasing the IC50 of 5-FU to the gastric cancer cells.However, transfection with SIRT1 plasmid decreased the cytotoxicity of DHA and 5-FU co-treatment to the BGC-823 cells.DHA promoted the production of ROS and phosphoryla-tion of ASK1 and JNK induced by 5-FU in the BGC-823 cells ( P<0.05 ) .However , ROS scavenger N-acetylcysteine ( NAC) or JNK specific inhibitor SP600125 inhibited the cell death and activation of caspase-9 and caspase-3 induced by DHA and 5-FU co-treatment (P<0.05).In addition, NAC significantly inhibited the phosphorylation of JNK in the BGC-823 cells co-treated with DHA and 5-FU.However, treatment with SP600125 did not influence the ROS production in the BGC-823 cells, indicating that JNK was the downstream target of ROS pathway .CONCLUSION: Combination of DHA with 5-FU induces caspase-dependent apoptosis in gastric cancer cells through the SIRT 1/NADPH oxidase/ROS/JNK sig-naling pathway .

Anti-proliferative and apoptotic effects of S1, a tetrandrine derivative, in human gastric cancer BGC-823 cells.

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the mRNA and protein expression levels in mitochondrial pathway. S1 significantly reduced cell viability and induced a G2/M phase arrest and apoptosis in dose- and time-dependent manner. Further studies showed that S1 increased mRNA and protein expression of Bax and the Bax/Bcl-2 ratio. Moreover, S1 decreased the protein expression of procaspase-9 and procaspase-3, suggesting that the induction of apoptosis may be related to the alteration of the ratio of Bax/Bcl-2 and the activation of caspases. These findings suggested that S1 merits further investigation as a novel therapeutic agent for the treatment of human gastric cancer.

Anti-proliferative and apoptotic effects of S1, a tetrandrine derivative, in human gastric cancer BGC-823 cells / 中国天然药物

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the mRNA and protein expression levels in mitochondrial pathway. S1 significantly reduced cell viability and induced a G2/M phase arrest and apoptosis in dose- and time-dependent manner. Further studies showed that S1 increased mRNA and protein expression of Bax and the Bax/Bcl-2 ratio. Moreover, S1 decreased the protein expression of procaspase-9 and procaspase-3, suggesting that the induction of apoptosis may be related to the alteration of the ratio of Bax/Bcl-2 and the activation of caspases. These findings suggested that S1 merits further investigation as a novel therapeutic agent for the treatment of human gastric cancer.

Role of mimic of manganese superoxide dismutase in proliferation and apoptosis of gastric carcinoma BGC-823 cells in vitro and in vivo.

The aim of this study was to investigate the anti-cancer effect and mechanism of mimic of manganese superoxide dismutase (MnSODm) in gastric carcinoma cells in vitro and in vivo. The MTT was used to measure cytotoxicity of the MnSODm. The appearance of apoptotic BGC-823 cells was detected by flow cytometry analysis. Apoptosis proteins, caspase family and Bcl-2 family were viewed by Western blotting. The phosphoinositide 3 kinase (PI3K)/Akt signaling pathway and the NF-κB pathway were also examined. PI3K inhibitor LY294002 was used to examine the involvement of the PI3K/Akt signaling pathway in this apoptosis-inducing effect. BGC-823 cell xenograft serious combined immunodeficiency disease mice were used for the in vivo study. The result showed that MnSODm could induce growth arrest and apoptosis of BGC-823 cells in vitro and in vivo. Further analysis demonstrated the involvement of activation of caspase cascade in MnSODm induced apoptosis. The expression of anti-apoptotic Bcl-2 was decreased, whereas the expression of pro-apoptotic Bax protein was increased. The main mechanisms on MnSODm-induced apoptosis were related to the inhibition of PI3K expression, which inactivated the phosphorylation of Akt involving the prevention of NF-κB phosphorylation and nuclear translocation. This phenomenon could be inhibited by the PI3K inhibitor LY294002. We demonstrated that the mechanisms of MnSODm inhibited the BGC-823 cell proliferation in vitro primarily are related to the induced apoptosis, which appears to be regulated by the PI3K/Akt pathway involving the prevention of NF-κB nuclear translocation, and then triggering the activation of the caspase cascades. Moreover, the anticancer effect in vivo on BGC-823 cells xenografted mice was also due to MnSODm-mediated apoptosis.

Anti-proliferation Effect of Carvacrol on Human Gastric Cancer Cells / 中国药师

Objective:To investigate the anti-proliferation effect of carvacrol on human gastric cancer cell BGC-823 and explore the molecular mechanism. Methods:The proliferation of BGC-823 cells was evaluated by MTT assay. Flow cytometry was used to ana-lyze the cell apoptosis after exposed to carvacrol. Transwell assay was used to analyze the effect of carvacrol on cell metastasis. Quanti-tative realtime-PCR was used to detect the expression of MMP-9 and TIMP-1. The expression of caspase-9 and PARP,and the activa-tion of ERK and P38 were detected by Western blot. Results:The incubation with carvacrol resulted in a significant inhibition of BGC-823 cell proliferation. After the treatment with carvacrol,the apoptotic rate was significantly increased( 0 μmol · L-1 vs 10 μmol · L-1 ,P<0. 000 1;0 μmol·L-1 vs 20 μmol·L-1 ,P<0. 000 1;0 μmol·L-1 vs 40 μmol·L-1 ,P<0. 000 1;0 μmol·L-1 vs 80μmol·L-1 ,P<0. 000 1)and the invasion ability was decreased(0 μmol·L-1 vs 80 μmol·L-1 ,P<0. 000 1). The expression of caspase-9(0 μmol·L-1 vs 80 μmol·L-1,P<0. 000 1)and TIMP-1 was increased(P<0. 000 1),PRAP fragment occurred(P<0. 000 1)and P38 signaling pathway was activated in the carvacrol treated group,while the expression of MMP-9 activity of ERK signa-ling pathway was inhibited(P<0.000 1). Conclusion:Carvacrol can inhibit cell growth and invasion,and induce cell apoptosis, which is closely related to MAPK signaling pathway.