Gastric Cancer Cell Lines BGC-823 Research Articles

Design, synthesis, and evaluation of (1E,4E,6E)-1,7-diphenyl hepta-1,4,6-trien-3-one analogues-inspired o-methoxy phenyl group as potential anti–gastric cancer agents.

292 Background: Gastric cancer (GC) is a major global malignancy causing significant mortality. Most diagnoses occur at advanced stages. Current treatments involve surgery, chemotherapy, and targeted therapies. Targeted drugs face resistance and side effects. Curcumin, derived from Curcuma longa, shows promise against GC. Improved analogs addressing bioavailability have been developed. Some curcumin-based compounds with o-methoxy phenyl groups exhibit enhanced anticancer activity. We designed and synthesized (1E,4E,6E)-1,7-diphenyl hepta-1,4,6-trien-3-one analogs inspired by o-methoxy phenyl for anti-gastric cancer evaluation in vitro and in vivo. Methods: We designed and synthesized a series of analogs named (1E,4E,6E)-1,7-diphenyl hepta-1,4,6-trien-3-one analogues inspired by the o-methoxy phenyl group based on association theory. Anti-tumor activity was evaluated in vitro using gastric cancer cell lines BGC-823 and SGC-7901. Compound 2 was selected as a prime candidate based on its potency. Results: Compound 2 demonstrated potent anti-tumor effects in vitro by suppressing growth, migration, and invasion of SGC-7901 and BGC-823 cells. Impressively, it prompted cell cycle arrest at the G2/M phase and initiated apoptosis through Bax activation and caspase 3 inhibition. Moreover, in vivo trials on xenograft model nude mice validated the compound's substantial anti-gastric cancer potential while maintaining a favorable safety profile. Conclusions: A group of curcumin analogs exhibiting strong anti-gastric cancer activity was developed. The active compound 2 is capable of inhibiting the growth, colony formation, migration, and invasion of gastric cancer cells. It also arrests the cell cycle at the G2/M phase and stimulates the expression of apoptosis-related proteins, showcasing a powerful anti-gastric cancer effect in vitro. Furthermore, it demonstrates significant anti-gastric cancer activity in vivo while maintaining a favorable safety profile. Our research underscores the potential of (1E, 4E, 6E)-1,7-diphenylheptyl-1,4,6-trien-3-one analogs with o-methoxyphenyl in combatting tumors and highlights their promise as a secure anti-tumor candidate drug.

Forkhead Box M1 Regulates the Proliferation,Invasion,and Drug Resistance of Gastric Cancer Cells via circ_NOTCH1

Objective To investigate the impacts of forkhead box M1(FOXM1)on the proliferation,invasion,and drug resistance of gastric cancer cells by regulating the circular RNA circ_NOTCH1.Methods Western blotting and real-time quantitative PCR were performed to determine the expression of FOXM1 protein and circ_NOTCH1,respectively,in the gastric cancer tissue,para-carcinoma tissue,human normal gastric mucosa epithelial cell line GES-1 and gastric cancer cell lines MGC-803,HGC-27,and BGC-823.BGC-823 cells were classified into the following groups:control,short hairpin RNA FOXM1(sh-FOXM1)and negative control(sh-NC),small interfering RNA circ_NOTCH1(si-circ_NOTCH1)and negative control(si-NC),and sh-FOXM1+circ_NOTCH1 overexpression plasmid(sh-FOXM1+pcDNA-circ_NOTCH1)and sh-FOXM1+negative control(sh-FOXM1+pcDNA).CCK-8 assay and clone formation assay were employed to measure the cell proliferation,and Transwell assay to measure cell invasion.After treatment with 1.0 mg/L adriamycin for 48 h,the cell resistance in each group was analyzed.Western blotting was employed to determine the expression levels of FOXM1,proliferating cell nuclear antigen(PCNA),Bax,multi-drug resistance-associated protein 1(MRP1),and multi-drug resistance gene 1(MDR1).RNA pull-down and RNA immunoprecipitation were employed to examine the binding of circ_NOTCH1 to FOXM1 protein.Results Compared with those in the para-carcinoma tissue,the expression levels of FOXM1 protein and circ_NOTCH1 in the gastric cancer tissue were up-regulated(all P<0.001).Compared with GES-1 cells,MGC-803,HGC-27,and BGC-823 cells showed up-regulated expression levels of FOXM1 protein and circ_NOTCH1(all P<0.001).Compared with the control group and sh-NC group,the sh-FOXM1 group with down-regulated expression of FOXM1 protein and circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with the control group and the si-NC group,the si-circ_NOTCH1 group with down-regulated expression of circ_NOTCH1 showed decreased optical density value,clone formation rate,cell invasion number,and cell viability,down-regulated expression of PCNA,MRP1,and MDR1,and up-regulated expression of Bax protein in BGC-823 cells(all P<0.001).Compared with sh-FOXM1 group and sh-FOXM1+pcDNA group,the sh-FOXM1+pcDNA-circ_NOTCH1 group with up-regulated expression of circ_NOTCH1 showed increased optical density value,clone formation rate,cell invasion number,and cell viability,up-regulated expression of PCNA,MRP1,and MDR1,and down-regulated expression of Bax protein(all P<0.001).FOXM1 protein was able to interact with circ_NOTCH1.Conclusion Interference with FOXM1 may inhibit the proliferation,invasion,and drug resistance of gastric cancer cells by silencing circ_NOTCH1 expression.

Butyrate Inhibits Gastric Cancer Cells by Inducing Mitochondriamediated Apoptosis.

Gastric cancer (GC) remains a common cause of cancer death in East Asia. Current treatment strategies for GC, including medical and surgical interventions, are suboptimal. Butyrate, a short-chain fatty acid produced by the intestinal flora, has been reported to be able to inhibit gastric carcinogenesis. This study aimed to investigate the effects of butyrate on human GC and its underlying mechanisms. Human GC cell lines BGC-823 and SGC-7901, human GC tissues and adjacent normal tissues were used for this study. Cell proliferation was assessed using CCK-8 and EdU staining. TUNEL fluorescence and Annexin V/PI staining were adopted for qualitative and quantitative evaluation of cell apoptosis, respectively. Reactive oxygen species (ROS) assay was performed to analyse mitochondrial function. Real-time q-PCR and western blot were carried out to examine the expression of apoptosis-related genes and the synthesis of apoptosis-related proteins. The association between G protein-coupled receptor 109a (GPR109a) and GC prognosis was analyzed using data from The Cancer Genome Atlas (TCGA). CCK-8 and EdU staining confirmed inhibitory activities of butyrate against human GC cells. Annexin V/PI staining and TUNEL fluorescence microscopy showed that butyrate promoted GC cell apoptosis. No difference in the expression of GPR109a was found between GC tissues and adjacent normal tissues, and no direct association between GPR109a and GC prognosis was discovered, suggesting that GPR109a may not be a key factor mediating the apoptosis of GC cells. Butyrate increased the synthesis of caspase 9 and decreased BCL-2, the well-known effector and regulator of mitochondria-mediated apoptosis, and significantly induced mitochondrial ROS. Collectively, our results suggest that butyrate is able to inhibit the proliferation of GC cells and induce GC apoptosis, possibly via a mitochondrial pathway.

Ginsenoside induces apoptosis, autophagy and cell cycle arrest in gastric cancer cells by regulation of reactive oxygen species and activation of MAPK pathway

Purpose: To study the influence of ginsenoside on apoptosis, cell cycle and autophagy in gastric carcinoma (GC), and its effect on reactive oxygen species (ROS) levels and the mitogen-activated protein kinase (MAPK) pathway. &#x0D; Methods: Human gastric cancer cell line BGC-823 was randomly divided into the following groups: control, 100 μM ginsenoside (Rg5), 150 μM Rg5, and 200 μM Rg5 groups. Western blot assay was used to determine the expressions of autophagy-associated protein 12 (Atg12), Beclin-1, lc3b II, cycle-related protein, phosphated mitotic cyclin 25 homologous protein C (p-cdc25c), cyclin B1, and MAPK signaling pathway-related proteins. &#x0D; Results: There was significantly higher apoptosis in Rg5-treated BGC-823 cells than in untreated cells. Relative protein levels of Beclin-1, Atg5, Atg12, and lc3b II in BGC-823 cells in Rg5 groups were significantly and concentration-dependently up-regulated, relative to the corresponding expression levels in untreated cells. There were markedly up-regulated proteins of p-cdc25c, cyclin B1 and p-cdc2 in Rg5-exposed BGC-823 cells than in untreated cells, while CDC2 protein expression was significantly and concentration-dependently lower than that of control group (p &lt; 0.05). Rg5 treatment resulted in marked and concentration-dependent increases in ROS levels in BGC-823 cells, relative to control cells (p &lt; 0.05), whereas the expression levels of p-p38, p-JNK and p-ERK were significantly higher in Rg5-exposed cells than in unexposed cells (p &lt; 0.05). &#x0D; Conclusion: Ginsenoside induces apoptosis, autophagy and cycle interruption in GC cells by regulating ROS production and activating MAPK pathway. Therefore, ginsenoside may be a promising agent for the management of gastric cancer. However, there is a need to conduct in vivo studies on the compound.

Retraction.

Retraction: "Curcumin derivative L6H4 inhibits proliferation and invasion of gastric cancer cell line BGC-823," by Jianfeng Mu, Xiaodong Wang, Lihua Dong, and Pengda Sun, J Cell Biochem. 2019; 1011-1017: The above article, published online on September 22, 2018, in Wiley Online Library (https://doi.org/10.1002/jcb.27542) has been retracted by agreement between the authors, the journal's Editor in Chief, Prof. Dr. Christian Behl, and Wiley Periodicals LLC. The retraction has been agreed following an investigation based on allegations raised by a third party, and a request for correction by the authors. A detailed investigation revealed several flaws and inconsistencies between the results presented and experimental methods. Additionally, duplications were found in Figures 2A,Cand 4B. As a consequence, the editors consider the conclusions of this article to be invalid.

GM-CSF-miRNA-Jak2/Stat3 Signaling Mediates Chemotherapy-Induced Cancer Cell Stemness in Gastric Cancer.

Chemotherapy serves as the first choice in clinic to treat advanced gastric cancer. However, emerging evidence indicated the induction of drug resistance and cancer stem cells occasionally by chemotherapy, which seriously limit the therapeutic effects, but the regulatory mechanism remains unclear. Here we treated two human gastric cancer cell lines SGC7901 and BGC823 with 5-Fluorouracil (5-Fu) or Cisplatin (DDP) in vitro. The survived cells showed significant increase of drug resistance, cell stemness and cytokine GM-CSF expression and secretion. As such, GM-CSF was applied to stimulate gastric cancer cells, followed by the subpopulation of CD133 + CSC analysis, sphere formation assay and stemness genes expression analysis. As a result, CSCs showed induction by GM-CSF treatment. A gastric cancer animal model further indicated that the gastric cancer cells significantly promoted tumor growth after GM-CSF treatment in vivo. High-throughput miRNA and mRNA sequencing analyses identified a subset of miRNAs and mRNAs under regulation of both 5-Fu and GM-CSF in gastric cancer cells, including upregulation of miR-877-3p and downregulation of SOCS2. Targeted overexpression or knockdown of miR-877-3p in gastric cancer cells revealed the oncogenic function of miR-877-3p in regulating gastric cancer by suppressing target gene SOCS2. Jak2/Stat3 signaling pathway, as a downstream target of SOCS2, showed activation in vitro and in vivo after treatment with miR-877-3p or GM-CSF. Our findings not only revealed a novel mechanism through which chemotherapy induced CSCs in gastric cancer via GM-CSF-miRNA-Jak2/Stat3 signaling, but also provided an experimental evidence for appropriate dose reduction of adjuvant chemotherapy in treatment of cancer patients.

LSD1 inhibitors from the roots of Pueraria lobata

One new 6a,11a-dehydropterocarpan derivative, 6-O-methyl-anhydrotuberosin (1), one new 6a-hydroxypterocarpan, (6aR,11aR,11bR)-hydroxytuberosone (7), and seven known compounds including two 6a,11a-dehydropterocarpans (2 and 4), two coumestans (3 and 5), one isoflavonoid (6) and two other phenolic compounds (8 and 9) were isolated from the roots of Pueraria lobata. The structures of the isolated compounds were elucidated with spectroscopic and spectrometric methods (1 D and 2DNMR, HRESIMS). Compounds 1, 2, 4–5 showed potent LSD1 inhibitory activities with IC50 values ranging from 1.73 to 4.99 μM. Furthermore, compound 2 showed potent cytotoxicity against gastric cancer cell lines MGC-803 and BGC-823, and lung cancer cell lines H1299 and H460.

Effect of lentivirus-mediated peroxiredoxins 6 gene silencing on the phenotype of human gastric cancer BGC-823 cells.

Peroxiredoxins (PRDX6) regulates the occurrence and progression of cancer. The aim of this study is to investigate the effect of PRDX6 knockdown on the biological behavior of human gastric cancer cell line BGC-823 cells. Research article. The differential expression of PRDX6 in gastric cancer and normal gastric tissues was tested by immunohistochemistry. Ribonucleic acid plasmid of PRDX6 gene was packaged using a lentivirus, and BGC-823 cells were transfected with the lentivirus to obtain a BGC-823 cell line in which the expression of PRDX6 was stably silenced. The proliferation activity of BGC-823 cells was detected using the cell counting kit-8 method. The effect of PRDX6 on the migration and invasion of BGC-823 cells was evaluated using the scratch test and Transwell assay, and the expression of related proteins was detected by western blot. The expression of PRDX6 in gastric cancer was significantly increased (P < 0.05). Compared with those in the untransfected and negative control groups. The proliferation, migration, and invasion of gastric cancer BGC-823 cells were significantly inhibited, and the apoptotic rates were significantly increased in the lentivirus-transfected (short hairpin-PRDX6) group. Western blot analysis showed that the expression of Bax protein increased, whereas that of proliferating cell nuclear antigen, Bcl-2, PI3K, phospho (p-Akt), and phosphorylated-mammalian target of rapamycin (mTOR) decreased significantly compared with that in WT and vector groups (P < 0.05). The knockdown of PRDX6 gene expression in BGC-823 cells can inhibit the proliferation, migration, and invasion of gastric cancer cells and promote apoptosis, thereby affecting gastric cancer cells.

Effects of long-chain noncoding RNA Linc00673 overexpression on proliferation and apoptosis of gastric cancer cell line MGC-803

Objective: To investigate the effects of long-chain noncoding RNA Linc00673 overexpression on proliferation and apoptosis of gastric cancer cells and its mechanisms. Methods: The recombinant lentivirus expressing plasmid pLVX-Linc00673 and the control empty plasmid pLVX-NC were packaged and amplified in 293T cells, and the recombinant lentivirus was transfected into gastric cancer cell line MGC-803 to establish a cell line stably overexpressing Linc00673. The expression of Linc00673 gene was detected by real-time fluorescence quantitative PCR. The growth and proliferation of cells were observed by MTT assay and clone formation assay. Cell cycle and apoptosis were detected by flow cytometry. The expressions of cell cycle related regulatory genes were detected by qPCR. The expressions of key molecules in the PI3K/Akt signaling pathway and tumor proliferation related proteins were detected by Western blot. Results: The expressions of Linc00673 in gastric cancer cell line MGC-803, BGC-823 and AGS were significantly higher than that in normal gastric mucosa cell line GES-1 (P＜0.05). MGC-803 cell line with stable overexpression of LINC00673 was established, and the expression level of LincC00673 was 200 times higher than that of the control empty carrier group. Overexpression of Linc00673 promoted proliferation of MGC-803 cells (P＜0.05) and clone formation (P＜0.05), inhibited cell apoptosis and affected the G1→S phase progression of cell cycle (P＜0.01). Overexpression of Linc00673 could affect the expressions of cell cycle regulatory gene CCNG2, P19 and CDK1 in MGC-803. Western blot showed that Linc00673 overexpression not only promoted the expressions of the key molecule pAkt in PI3K / Akt signaling pathway and its downstream target NF-κ B and Bcl-2 protein, but also up regulated the expressions of tumor related factors β-catenin and EZH2 proteins. Conclusion: Overexpression of Linc00673 may promote proliferation and inhibit apoptosis of MGC-803 cells through PI3K/Akt signaling pathway.

CCNI2 promotes the progression of human gastric cancer through HDGF

BackgroundGastric cancer is a highly aggressive malignant tumor with heterogeneity and is still a global health problem. The present study aimed to investigate the role of Cyclin I-like (CCNI2) in the regulation of phenotype and tumorigenesis, as well as its underlying mechanisms.MethodThe expression profile of CCNI2 in gastric cancer was determined based on The Cancer Genome Atlas (TCGA) database and immunohistochemical staining. The effects of altered CCNI2 expression on the biological phenotypes such as proliferation, clone formation, apoptosis and migration of gastric cancer cell lines BGC-823 and SGC-7901 were investigated. Mice xenograft models were established to reveal the role of CCNI2 knockdown on tumorigenesis. The potential mechanism of CCNI2 regulating gastric cancer was preliminarily determined by RNA sequencing.ResultCCNI2 was abundantly expressed in gastric cancer and was positively correlated with pathological stage. Knockdown of CCNI2 slowed down the malignant progression of gastric cancer by inhibiting tumor cell proliferation, increasing the susceptibility to apoptosis and suppressing migration. Moreover, downregulation of CCNI2 attenuated the ability of gastric cancer cells to form tumors in mice. Additionally, there was an interaction between CCNI2 and transcription factor hepatoma-derived growth factor (HDGF) in SGC-7901 cells. Knockdown of CCNI2 alleviated the promoting effects of HDGF overexpression in gastric cancer cells.ConclusionsCCNI2 promoted the progression of human gastric cancer through HDGF, which drew further interest regarding its clinical application as a potential therapeutic target.

Endogenous NO-releasing Carbon Nanodots for Tumor-specific Gas Therapy

Carbon nanodots based on L-arginine (L-Arg) were developed for enhanced nitric oxide (NO) gas therapy for cancer. The L-Arg-based carbon nanodots (Arg-dots) produced high levels of NO in the tumor environment rich in endogenous H2O2. In vitro cell experiments revealed that the Arg-dots could kill tumor cells (including human breast cancer cell line MCF-7, female gastric cancer cell line BGC-823, male lung cancer cell line A549, and female leukemic cell line K562) but did not affect the activity of normal cells (human normal lung epithelial cell line BEAS-2B). The Arg-dots produced twice the amount of NO for an equivalent amount of L-Arg. Theoretical calculations showed that the carbonization structure of the Arg-dots promoted significantly more electrons toward the guanidinium groups of L-Arg and boosted the adsorption of H2O2 molecules. In vitro and in vivo investigations confirmed that the Arg-dots reduced the multidrug resistance (MDR) effect of the tumor cells (MCF-7/ADR cells) and produced a combined antitumor efficacy with traditional chemotherapeutic drugs (adriamycin [ADR]). The fluorescence property (quantum yield, 6.88%) allows the Arg-dots to be used as a suitable fluorescent probe for fluorescence imaging of tumor cells. The ultra-small size of the Arg-dots (diameter: ca. 2.5 nm) enables them not only to penetrate deep tumors and provide enhanced antitumor activity but also to be removed through kidney filtration and have a renal clearance property. Statement of significanceNitric oxide (NO), which serves as a biological messenger, can be used in gas therapy for cancer. The development of a safe and efficient NO cancer therapy is, however, challenging because of the low NO release amount and poor tumor specificity of most NO donors. Many efforts have been made to overcome these drawbacks, but solving both these limitations through a single approach has been seldom achieved. In the present work, carbon nanodots (Arg-dots) from L-arginine were used for gas therapy of cancer. The Arg-dots produced NO in the H2O2-rich tumor environment. Theoretical calculations were consistent with the mechanism of enhanced NO release amount. The Arg-dots also reduced the multidrug resistance effect in cancer chemotherapy. In vivo and in vitro toxicity assessments confirmed that the Arg-dots have excellent biosafety.

Molecular Mechanism of 73HOXC-AS1-Activated Wntβ-Catenin Signaling and eIF4AIII in Promoting Progression of Gastric Cancer.

Objective This study is aimed at exploring the regulatory mechanism of 73HOXC-AS1 overexpression plasmid-activated Wntβ-catenin classic signaling pathway and eukaryotic initiation factor 4A (eIF4AIII) expression increased by lentivirus-eIF4AIII-RNAi (44682-1) (LV-eIF4AIII-RNAi (44682-1)). Methods Focusing on the occurrence and progression of gastric cancer, the human gastric cancer cell line BGC823 (University Experimental Center) was taken as the research object and was transfected after subculture. According to the different ways of transfection, the cells were divided into the P1 group (LV-eIF4AIII-RNAi (44682-1) overexpressed plasmid), the P2 group (pcDNA-HOXC-AS1 overexpressed plasmid), the P3 group (LV-eIF4AIII-RNAi (44682-1) + pcDNA-HOXC-AS1), and the P4 group (no transfection, control group). Cell proliferation was detected by CCK-8 (Cell Counting Kit-8) assay, Western blotting was adopted to detect Wnt3a and P-GSK3β proteins, Transwell assay was adopted to detect the ability of cell migration and invasion, and cell cycle and apoptosis were detected by flow cytometry. Results The results show that the protein expression levels of Wnt3a and P-GSK3β (glycogen synthase kinase-3β) in the P1 and P4 groups were lower than those in the P2 and P3 groups (P < 0.05). The cell activity and clone number of BGC823 in the P3 group were higher than those in the P1, P2, and P4 groups (P < 0.05). The apoptosis rate of BGC823 cells in the P3 group was significantly higher than those in the P1, P2, and P4 groups (P < 0.05). The proportion of BGC823 cells in the P3 group at the S phase was significantly higher than those in the P1, P2, and P4 groups, while the proportion in the G2 phase was significantly lower than those in the P1, P2, and P4 groups (P < 0.05). The number of migrating and invading BGC823 cells in the P3 group was significantly higher than those in the P1, P2, and P4 groups, while the number of migrating BGC823 cells in the P4 group was significantly lower than those in the P1 and P2 groups (P < 0.05). Conclusion The 73HOXC-AS1 overexpression plasmid-activated Wntβ-catenin classic signaling pathway and eIF4AIII expression increased by LV-eIF4AIII-RNAi (44682-1) could act together on BGC823 cells to improve cell proliferation activity, migration, and invasion; inhibit cell apoptosis; and prevent cells from entering the S phase.

Monobenzone, a Novel and Potent KDM1A Inhibitor, Suppresses Migration of Gastric Cancer Cells.

Lysine-specific demethylase1 (KDM1A) is generally highly expressed in various cancer tissues, and promotes the initiation and development of cancers via diverse cellular signaling pathways. Therefore, KDM1A is a promising drug target in many cancers, and it is crucial to find effective KDM1A inhibitors, while none of them has entered into market. With the help of compound library, monobenzone, a local depigmentor using as a treating over-pigmentation in clinic, was characterized as an effective KDM1A inhibitor (IC50 = 0.4507 μM), which may competitively inhibit KDM1A reversibly. Further cellular study confirmed that monobenzone could inhibit the proliferation of gastric cancer cell lines MGC-803 and BGC-823 with IC50 as 7.82 ± 0.55 μM and 6.99 ± 0.51 μM, respectively, and erase the substrate of KDM1A, H3K4me1/2 and H3K9 me2, and inhibit the migration of gastric cancer cell by reversing epithelial–mesenchymal transition (EMT). As the structure of monobenzone is very simple and small, this study provides a novel backbone for the further optimization of KDM1A inhibitor and gives monobenzone potential new application.

Knockdown of Gastrin Promotes Apoptosis of Gastric Cancer Cells by Decreasing ROS Generation.

Overexpressed gastrin is reported to promote oncogenesis and development of gastric cancer by inhibiting apoptosis of cancer cells; however, the underlying mechanism remains unclear. Our study is aimed at revealing the mechanism underlying the effect of gastrin on apoptosis of gastric cancer cells. Gastrin-interfering cell line was constructed by stably transfecting gastrin-specific pshRNA plasmid to gastric cancer cell line BGC-823. Then, differentially expressed proteins between untreated BGC-823 and gastrin-interfering BGC-823 cell lines were detected by the iTRAQ technique. GO and KEGG analysis was used to analyze the differentially expressed genes that code these differentially expressed proteins. The Annexin V-FITC staining assay was used to detect gastric cancer cell apoptosis. The DCFH-DA fluorescent probe staining assay was used to measure intracellular ROS. Mitochondrial membrane potential was detected by flow cytometry. Western blot was used to analyze the mitochondria respiratory chain proteins and apoptosis-related proteins. A total of 107 differentially expressed proteins were identified by iTRAQ. GO and KEGG analysis showed that proteins coded by the corresponding differentially expressed genes were mainly enriched in the mitochondrial oxidative respiratory chain, and the expression of three proteins (COX17, COX5B, ATP5J) was upregulated. The three proteins with higher scores were verified by Western blot. The apoptosis rate of the gastrin knockdown cancer cell was significantly increased; meanwhile, gastrin knockdown leads to increase of membrane potential and decrease of intracellular ROS production. Additionally, Bax was significantly increased, whereas NF-κB-p65 and Bcl-2 were downregulated after knockdown of gastrin. Concomitantly, pretreatment with NAC reversed the effect of gastrin on the Bax and Bcl-2 expression. Gastrin promotes the production of ROS from mitochondria, activates NF-κB, and inhibits apoptosis via modulating the expression level of Bcl-2 and Bax.

Zinc Finger Protein CTCF Regulates Extracellular Matrix (ECM)-Related Gene Expression Associated With the Wnt Signaling Pathway in Gastric Cancer.

Gastric cancer (GC), a leading cause of cancer-related death, is a heterogeneous disease. We aim to describe clinically relevant molecular classifications of GC that incorporate heterogeneity and provide useful clinical information. We combined different gene expression datasets and filtered a 7-gene signature related to the extracellular matrix (ECM), which also exhibited significant prognostic value in GC patients. Interestingly, putative CCCTC-binding factor (CTCF) regulatory elements were identified within the promoters of these ECM-related genes and were confirmed by chromatin immunoprecipitation sequencing (ChIP-Seq). CTCF binding sites also overlapped with histone activation markers, indicating direct regulation. In addition, CTCF was also correlated with the Wnt signaling pathway. A comparison of human GC cell lines with high or low expression of ECM-related genes revealed different levels of tumor aggressiveness, suggesting the cancer development-promoting functions of ECM-related genes. Furthermore, CTCF regulated COL1A1 and COLA31 expression in vitro. Silencing CTCF or COL1A1/COL1A3 markedly inhibited cell growth and migration in the metastatic GC cell line BGC823. Collectively, this ECM-related 7-gene signature provides a novel insight for survival prediction among GC patients. The zinc finger protein CTCF regulates ECM-related genes, thereby promoting GC cell growth and migration.

The inhibitory effect of human DEFA5 in growth of gastric cancer by targeting BMI1.

Defensins, a class of small cysteine‐rich cationic polypeptides across cellular life, are identified as antimicrobial compounds that display direct antimicrobial and immune signaling activities that are involved in the host defense. In addition to their roles in the innate immune system, accumulating studies have reported that some members of defensins are expressed and involved in some cancer cells, such as colon cancer, colorectal cancer, lung cancer and renal cell carcinomas. However, the roles of α‐Defensin 5 (DEFA5) in tumorigenesis and development remain unknown. In the present study, bioinformatics analysis and quantitative PCR results showed that the expression level of DEFA5 was dramatically downregulated in human gastric cancer. Overexpression of human DEFA5 in gastric cancer cell lines SGC7901 and BGC823 effectively diminished cell proliferation and reduced the colony forming ability. Moreover, DEFA5 overexpression induced cell cycle arrest by significantly increasing the number of G1‐phase cells. Consistently, in vivo tumor formation experiments in nude mice showed the suppression of the tumor growth by DEFA5 overexpression, suggesting an inhibitory effect of DEFA5 in gastric cancer. Mechanistically, DEFA5 directly binds to BMI1, which subsequently decreased its binding at the CDKN2a locus and upregulated the expression of 2 cyclin‐dependent kinase inhibitors, p16 and p19. Taken together, we concluded that DEFA5 showed an inhibitory effect in gastric cancer cell growth and may serve as a potential tumor suppressor in gastric cancer.

CD133+/CD166+ human gastric adenocarcinoma cells present the properties of neoplastic stem cells and emerge more malignant features

AimsThe recurrence and metastasis of gastric cancer has always been an important factor affecting the prognosis of gastric cancer. Cancer stem cells can promote the recurrence and growth of gastric cancer. The identification and isolation of gastric cancer stem cells contribute to the origin, progress and treatment strategy of gastric cancer. The aim of this study was to identify and isolate gastric cancer stem cells, and provide targets for the treatment of gastric cancer. MethodsMagnetic-activated cell sorting was used to isolate CD133+/CD166+ cell populations from human gastric adenocarcinoma cell lines (BGC-823 and SGC-7901). Sphere formation, cell proliferation, resistance to chemotherapy, colony formation, migration invasion and tumorigenicity in vivo of these cell populations were evaluated. Moreover, RT-qPCR and Western blot were used to investigate the expression level of the stem cell markers Nanog, Sox2, Oct-4, and c-Myc. ResultsCD133+/CD166+ cell subpopulations presented more malignant features than CD133-/CD166-, CD133-/CD166+, CD133+/CD166- cell populations and parental cells. Moreover, the mRNA and protein expression level of Oct-4 and c-Myc were higher in CD133+/CD166+ cells than in parental cells or other cell populations. ConclusionThe CD133+/CD166+ populations of human gastric cancer cell lines BGC-823 and SGC-7901 have cancer stem cell characteristics.

VSNL1 Promotes Gastric Cancer Cell Proliferation and Migration by Regulating P2X3/P2Y2 Receptors and Is a Clinical Indicator of Poor Prognosis in Gastric Cancer Patients.

Purpose The aim of this study was to investigate the role of Visinin Like 1 (VSNL1) in the proliferation and migration of gastric cancer (GC) cells as well as its clinical prognostic significance. Methods To this end, we evaluated VSNL1 expression in GC tissues and cell lines by real-time PCR and immunohistochemistry. To further explore the effects of VSNL1, a lentiviral vector expressing a short hairpin RNA (shRNA) against VSNL1 was constructed and transduced into the GC cell lines BGC-823 and SGC-7901. The interference efficiency of VSNL1-shRNA was determined by western blot. The effects of VSNL1 on the migration and invasion of GC cells as well as the expression of P2X3/P2Y2 were explored using MTS, colony formation, migration, and western blot assays. Results VSNL1 mRNA and protein levels were increased in GC tissues and cell lines. Furthermore, VSNL1 expression was positively correlated with Lauren's classification, lymph node metastasis, distant metastasis, TNM stage, and prognosis. VSNL1 expression was inversely correlated with the 5-year survival rate of GC patients. VSNL1 expression was markedly reduced in cells transduced with lentivirus expressing shRNA against VSNL1, and inhibiting VSNL1 expression significantly suppressed cell growth, migration, and colony formation and reduced the expression of P2X3/P2Y2. Conclusion VSNL1 may promote the proliferation and migration of GC cells by regulating P2X3 and P2Y2 expression. VSNL1 plays important roles in GC development and metastasis and may be correlated with patient prognosis.

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

Ethno-pharmacological relevanceA natural ursolic compound, 2β,3β,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 methodsCell 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. ResultsIn 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. ConclusionsTUA 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.

6,12-Diphenyl-3, 9-diazatetraasterane-1, 5, 7, 11-tetracarboxylate Inhibits Proliferation, Migration and Promotes Apoptosis in Ovarian Cancer Cells.

6,12-Diphenyl-3,9-diazatetraasterane-1, 5, 7, 11-tetracarboxylate (DDTC) has been synthesized by the photodimerization of 4-phenyl-1,4-dihydropyridine-3,5-dicarboxylate. The potential of theercvantitumor activity and mechanism were investigated in vitro using MTT assay in human lung cancer cell line A549, ovarian cancer cell lines SKOV3 and A2780, breast cancer cell line MCF-7, gastric cancer cell line BGC-823, colon cancer cell line HT29, prostate cancer cell line DU145, and liver cancer cell line SMMC7721. The results show that DDTC can inhibit the growth of ovarian cancer SKOV3 and A2780 cells. The best IC50 value is approximately 5.29 ± 0.38 and 4.29 ± 0.39 μM, respectively. DDTC induced the cell cycle arrest in the G2 phase by flow cytometric analysis. The migration and invasion of ovarian cancer SKOV3 and A2780 cells were inhibited by DDTC. DDTC could increase the expression protein level of E-cadherin in A2780 cells and ascend the expression protein and mRNA levels of E-cadherin in SKOV3 cells. DDTC could also decrease the protein and mRNA expression of EMT (epithelial-to-mesenchymal transition) markers of N-cadherin and Vimentin. mRNA and protein expression level of checkpoint kinase 1 (Chk1) were significantly increased and expressions of cyclin-dependent kinase (CDK1) and cell division cycle 25a (Cdc25a) were decreased in the SKOV3 and A2780 cell lines. Moreover, DDTC induced apoptosis by the cleavage and activation of caspase 3 and caspase 9.