Gastric Carcinoma Cell Lines Research Articles

Gold Nanoparticles Prepared with Phyllanthus emblica Fruit Extract and Bifidobacterium animalis subsp. lactis Can Induce Apoptosis via Mitochondrial Impairment with Inhibition of Autophagy in the Human Gastric Carcinoma Cell Line AGS.

(1) Background: Nanotechnology is being widely applied for anticancer strategies with few side effects. Nanoparticles (NPs) prepared from natural extracts are promising candidates for cancer treatment because of their unique physicochemical characteristics. This study aimed to prepare gold nanoparticles (AuNPs) from Phyllanthus emblica fruit extract (PEFE) using Bifidobacterium animalis subsp. lactis (B. lactis) and to evaluate their anticancer activity against the human gastric adenocarcinoma cell-line (AGS). (2) Methods: The safety of microbial biosynthesis AuNPs (PEFE-AuNPs) was assessed by evaluating the cytotoxicity. The anticancer activity of PEFE-AuNPs was investigated in AGS cells in terms of apoptosis and autophagy. (3) Results: PEFE-AuNPs exhibited significant cytotoxicity against AGS cells but not against normal cells. The apoptosis induced by PEFE-AuNPs in AGS cells was associated with PTEN-induced kinase 1 (PINK1)-Parkin mediated reduction of mitochondrial membrane potential and activation of intracellular signaling apoptosis pathways. The anticancer activity of PEFE-AuNPs was associated with induction of apoptosis through inhibition of autophagy, downregulation of LC3-II/LC3-I and Beclin-1 expression, and upregulation of p62 expression in AGS cells. (4) Conclusions: This study is the first to demonstrate the anticancer activity of PEFE-AuNPs against AGS cells. Our results provide a good starting point for the development of new anticancer products based on gold nanoparticles of P. emblica fruit extract.

Importance of Mevalonate Pathway Lipids on the Growth and Survival of Primary and Metastatic Gastric Carcinoma Cells.

PurposeThis preclinical study aims to determine the effect of drugs that alter isoprenoids and cholesterol metabolism in the homeostasis of gastric carcinoma cell lines in the search for new therapeutic targets for stomach cancer.Materials and MethodsPrimary (AGS) and metastatic (NCI-N87) gastric cancer cell lines were treated with simvastatin and terbinafine, two inhibitors of the mevalonate pathway, and avasimibe, an inhibitor of cholesterol esterification. Cell viability and growth were measured as well as cholesterol levels and the expression of the hydroxy methyl-glutaryl CoA reductase (HMGCR) and the LDL receptor (LDLR).ResultsPrimary and metastatic gastric carcinoma cells show different sensitivity to drugs that affect isoprenoid synthesis and the metabolism and uptake of cholesterol. Isoprenoids are involved in the growth and viability of both types of cells, but the role of free and esterified cholesterol for metastatic gastric cell survival is not as evident as for primary gastric cancer cells. Differential expression of LDLR due to mevalonate pathway inhibition suggests variations in the regulation of cholesterol uptake between primary and metastatic cancer cells.ConclusionThese results indicate that at least for primary gastric cancer, statins and avasimibe are promising candidates as potential novel antitumor drugs that target the metabolism of isoprenoids and cholesterol of gastric tumors.

Screening and identification of key genes in EBV-associated gastric carcinoma based on bioinformatics analysis

Epstein-Barr virus (EBV) infection is closely related to gastric carcinoma (GC). In this study, we identified a set of DEGs (different expression genes) between EBVaGC (EBV-associated gastric carcinoma) and EBVnGC (EBV-negative gastric carcinoma) through multiple bioinformatics analysis using the data from GEO (Gene Expression Omnibus) dataset GSE51575, and identified ten hub genes (CXCL10, C3, CXCL9, CXCL11, SST, ICAM1, CHRM2, NPY, GBP5 and GBP1). Therefore, we performed relevant survival analysis and immune infiltration analysis, then verified the mRNA expression in GC cell lines and TCGA database. CXCL11 was finally selected to be a potential biomarker for a better prognosis and tumor infiltrating. This may provide a new view about immune therapy for EBVaGC.

Proteasome Subunit Alpha Type 7 Promotes Proliferation and Metastasis of Gastric Cancer Through MAPK Signaling Pathway.

Proteasome subunit alpha type 7 (PSMA7) shows acarcinogenic effect on various human malignancies, but its role and regulatory mechanism in gastric carcinoma (GC) remain unclear. This study aimed to explore the role and mechanism of PSMA7 in GC. In this study, PSMA7 expressions in GC cells and tissues were detected, and relationships between PSMA7 and clinicopathological features were explored. Then, PSMA7 levels in human GC cells were intervened, and changes in cell biological behavior were observed in vitro and vivo. Key proteins and downstream factors of MAPK signaling pathway were detected after PSMA7 intervention. PSMA7 was upregulated in GC tissues and cell lines. PSMA7 overexpression was significantly associated with poor pTNM, cTNM stage, and high HP infection. PSMA7 can promote proliferation, invasion, and metastasis of GC cells in vitro and vivo. Furthermore, PSMA7 expression affected the phosphorylation level of JNK, P38, ERK and the expressions of their downstream factors Ap-1, c-myc, P53. PSMA7 can promote GC proliferation, invasion, and metastasis through MAPK signaling pathway in GC cells.

Membrane Filtration-Assisted Enzymatic Hydrolysis Affects the Biological Activity of Potato Juice.

The results of recently published studies indicate that potato juice is characterized by interesting biological activity that can be particularly useful in the case of gastrointestinal symptoms. Moreover, the studies also described the high nutritional value of its proteins. This article is a report on the impact of the enzymatic hydrolysis of proteins combined with membrane filtration. The obtained potato juice protein hydrolysate (PJPH) and its concentrate (cPJPH) were characterized in terms of their nutritional value and biological activity. The amino acid profile and scoring, the content of mineral compounds, and the antioxidant and in vitro cytotoxic activity were assessed. The study proved that the antioxidant activity of PJPH is higher than that of fresh potato juice, and the cytotoxicity against human gastric carcinoma cell line (Hs 746T), human colon cancer cell line (Caco-2), human colorectal adenocarcinoma cell line (HT-29), and human normal colon mucosa cell line (CCD 841 CoN) showed biological activity specifically targeted against cancer cells. Therefore, it can be concluded that the membrane filtration-assisted enzymatic hydrolysis of potato juice proteins may increase their biological activity and allow for potato juice to be used in the production of medicinal preparations.

An oncogenic lncRNA, GLCC1, promotes tumorigenesis in gastric carcinoma by enhancing the c-Myc/IGF2BP1 interaction.

Accumulating evidence has shown that long non-coding RNAs (lncRNAs) are vital regulators of the expression of various genes in multiple human diseases. The aim of this study was to investigate the role of glycolysis-associated lncRNA of colorectal cancer (GLCC1) in the progression of gastric carcinoma as well as the underlying mechanism. The expression levels of GLCC1 and c-Myc were determined in 47 pairs of gastric carcinoma tissues and cell lines using quantitative real-time polymerase chain reaction (qRT-PCR). Next, the functional roles of GLCC1 and c-Myc in the proliferation, apoptosis, migration, and invasion of gastric carcinoma cells (BGC823 and SGC7901 cells) were determined by siRNA-mediated knockdown of these molecules, and the cells were evaluated by Cell Counting Kit-8 (CCK-8), flow cytometry, and Transwell assays. In addition, RIP and RNA pull-down assays were used to examine the interaction between GLCC1 and c-Myc/IGF2BP1. Further mechanistic studies were conducted using western blotting. lncRNA GLCC1 and c-Myc were observed to be significantly increased in both gastric carcinoma tissues and cell lines. Knockdown of GLCC1 or c-Myc suppressed cell proliferation, migration, and invasion but promoted apoptosis in both the BGC823 and SGC7901 cell lines. Mechanistically, c-Myc was identified as a downstream regulator involved in the GLCC1-mediated biological effects in gastric carcinoma. The RNA pull-down and RIP assays further showed that the upregulation of lncRNA GLCC1 enhanced the interaction of the IGF2BP1 protein with c-Myc mRNA, thus promoting the stabilization of c-Myc mRNA. Altogether, we demonstrated that lncRNA GLCC1 modulates gastric cancer cell migration and invasion by enhancing the c-Myc/IGF2BP1 interaction, and lncRNA GLCC1 may serve as a potential therapeutic target for preventing the development and progression of human gastric carcinoma.

Inhibition of Glutamine Uptake Improves the Efficacy of Cetuximab on Gastric Cancer.

Treatment for advanced gastric cancer is challenging. Epidermal growth factor receptor (EGFR) contributes to the proliferation and development of gastric cancer (GC), and its overexpression is associated with unfavorable prognosis in GC. Cetuximab, a monoclonal antibody targeting EGFR, failed to improve the overall survival of gastric cancer patients indicated in phase III randomized trials. Glutamine is a vital nutrient for tumor growth and its metabolism contributes to therapeutic resistance, making glutamine uptake an attractive target for cancer treatment. The aim of the present study was to investigate whether intervention of glutamine uptake could improve the effect of cetuximab on GC. The results of MTT assay showed that by glutamine deprivation or inhibition of glutamine uptake, the viability of gastric carcinoma cells was inhibited more severely than that of human immortal gastric mucosa epithelial cells (GES-1). The expression of the key glutamine transporter alanine-serine-cysteine (ASC) transporter 2 (ASCT2; SLC1A5) was significantly higher in gastric carcinoma tissues and various gastric carcinoma cell lines than in normal gastric tissues and cells, as shown by immunohistochemistry and western blotting, while silencing ASCT2 significantly inhibited the viability and proliferation of gastric carcinoma cells. Consistent with previous studies, it was shown herein by MTT and EdU assays that cetuximab had a weak inhibitory effect on the cell viability of gastric carcinoma cells. However, inhibiting glutamine uptake by blockade of ASCT2 with l-γ-glutamyl-p-nitroanilide (GPNA) significantly enhanced the inhibitory effect of cetuximab on suppressing the proliferation of gastric cancer both in vitro and in vivo. Moreover, combining cetuximab and GPNA induced cell apoptosis considerably in gastric carcinoma cells, as shown by flow cytometry, and had a higher depressing effect on gastric cancer proliferation both in vitro and in vivo, as compared to either treatment alone. The present study suggested that inhibition of glutamine uptake may be a promising strategy for improving the inhibitory efficacy of cetuximab on advanced gastric cancer.

Platelet-derived growth factor-B signalling might promote epithelial-mesenchymal transition in gastric carcinoma cells through activation of the MAPK/ERK pathway.

IntroductionEpithelial-mesenchymal transition (EMT) is important in the metastasis of tumours and is triggered by several key growth factors, including platelet-derived growth factor-B (PDGF-B). But, whether PDGF-B signalling promotes EMT in gastric carcinoma cells is still unknown.Material and methodsWe established 2 gastric carcinoma cell lines (MKN28 and MKN45) to stably overexpress PDGF-B by lentiviral vectors, and expression of E-cadherin, N-cadherin, and ERK-1 were detected by western blot assay. Then, PDGF-B overexpression and normal MKN28 and MKN45 cells were cocultured with PDGFR-b positive fibroblast (hs738) and MAPK inhibitors were added; also, the expressions of ERK-1, E-cadherin, and N-cadherin were detected by western blot assay.ResultsAfter being cocultured with hs738 cells, expressions of ERK-1 and N-cadherin protein in PDGF-B overexpression MKN28 and MKN45 cells were much higher than normal MKN28 and MKN45 cells (p < 0.05), and those could be decreased by MAPK inhibitor. Also, expressions of E-cadherin protein in PDGF-B overexpression MKN28 and MKN45 cells were much lower than normal MKN28 and MKN45 cells (p < 0.05), and they could be increased by MAPK inhibitor.ConclusionsOur data indicate that PDGF-B signalling can induce EMT in gastric carcinoma cells. Thr tumour microenvironment is imperative in the process of PDGF-B signalling inducing EMT in gastric carcinoma cells. Also, activation of MAPK/ERK pathway, which is a downstream pathway of PDGF-B signalling, might participate in this process.

VRK1 promotes proliferation, migration, and invasion of gastric carcinoma cells by activating β-catenin.

Vaccinia-related kinase 1 (VRK1) is a member of the VRK subfamily belonging to the casein kinase superfamily, and it regulates the proliferation and survival of cells both in normal and malignant tissues. A variety of transcription factors including c-Jun can also be specifically phosphorylated and stimulated by VRK1. However, the regulatory mechanism of VRK1 in gastric carcinoma (GC) remains unclear. This research aimed to determine the function of VRK1 during tumor progression in GC. The mRNA and protein expression of the VRK1 and other genes were evaluated in GC cell lines using real-time RT-PCR and western blotting. Cell proliferation was analyzed using the cell count kit-8 (CCK-8) assay, and cell migration and invasion were monitored by the Transwell assay. The downregulated genes in shVRK1 cells compared with shCtrl were assessed using RNA-seq. The interactions of VRK1 with β-catenin or c-Jun were detected by co-IP. We found that VRK1 was overexpressed in gastric cancer cells, conversely, knockdown of VRK1 inhibits GC cells' proliferation, migration, and invasion. Moreover, VRK1 might regulate the expression of β-catenin (CTNNB1) at the transcriptional level by phosphorylating c-Jun, the transcriptional factor of β-catenin. VRK1 changes the subcellular location and decreases the nuclear aggregation of c-Jun by phosphorylating the Ser243 site. To conclude, VRK1 can affect migration and invasion by regulating the expression of β-catenin at the transcriptional level in GC cells.

Extracellular Acidity-mediated Expression of cPLA2γ Confers Resistance in Gastric Cancer Cells.

Extracellular acidity, a characteristic of solid tumors, has been proposed to be a critical factor for aggravating tumor malignancy and conferring resistance to therapeutics. Recently, acidity has been implicated in inflammatory responses, which are mediated through active lipid metabolites in various human tissues. In the present study, we investigated whether acidity can affect lipid-mediated signaling, and found that phospholipase A2 (PLA2) activity increased at acidic pH in SNU601 and AGS gastric carcinoma cell lines. To identify the PLA2 isoform that is responsible for the acidity-induced activity, we assessed mRNA levels of cPLA2 isotypes through real-time qPCR, and protein levels through immunoblot assay in cells cultured in acidic medium. It was found that acidic pH conditions markedly elevated the PLA2γ expression. A gene interference study using specific siRNA of cPLA2γ suggested that expression of cPLA2γ in acidic culture conditions may be associated with protection of cancer cells in acidic environment, as shown by cell viability and clonogenic assays. In addition, expression of cPLA2γ appeared to confer cell resistance to anticancer drugs under acidic pH conditions. Acidity-induced cPLA2γ expression may exert protective effects by imparting resistance to the gastric cancer cells under acidic environment.

TTC36 inactivation induce malignant properties via Wnt-β-catenin pathway in gastric carcinoma.

Objective: Tetratricopeptide repeat (TRP)-mediated cofactor proteins are involved in a wide range of cancers. TTC36 is little studied member of TRP subfamily. This study aimed to investigate the role of TTC36 in human gastric carcinoma (GC) and explore the potential underlying mechanisms.Methods: The analysis of TTC36 differential expression in GC was conducted using data from TCGA and a human tissue microarray. And effects of TTC36 expression on the prognosis of patients with gastric carcinoma were analyzed using the data from the GEO database. Lentivirus was transfected into the cell lines of AGS and BGC823 to construct overexpression and knocked down TTC36 cell model respectively. The effect of TTC36 expression on the growth, apoptosis and cell cycle of cells was explored in vitro. Downstream molecules were detected by western blotting. GSEA predicted signal pathway and related proteins were then detected.Results: TTC36 expression in human GC tissues was found significantly lower than that in adjacent normal tissues and closely related to clinical prognosis. The overexpression of TTC36 notably inhibited tumor progression, cell cycle G1/S transfer and increased apoptosis in AGS cells. Conversely, the opposite effects were observed when TTC36 was suppressed in BGC823 cells. The expression of cleaved caspase3, Survivin, cyclin D1 and c-Myc were consistent with the phenotype in TTC36 operated GC cell lines. Intriguingly, GSEA analysis predicted Wnt-β-catenin pathway involved in TTC36 induced effects in GC cells, expression of β-catenin and downstream molecules such as TCF4, c-jun and pAKT were found negative related to TTC36 expression in GC cells. Notably, treatment with the Wnt/β-catenin inhibitor XAV939 dramatically attenuated the effects of TTC36 in GC cells.Conclusion: These results signify a critical role for TTC36 as a tumor suppressor in gastric carcinoma via regulating Wnt-β-catenin pathway.

SATB1-Mediated Upregulation of the Oncogenic Receptor Tyrosine Kinase HER3 Antagonizes MET Inhibition in Gastric Cancer Cells.

MET-amplified gastric cancer cells are extremely sensitive to MET inhibition in vitro, whereas clinical efficacy of MET inhibitors is disappointing. The compensatory activation of other oncogenic growth factor receptors may serve as an underlying mechanism of resistance. In this study, we analyzed the role of HER receptors, in particular HER3 and its ligand heregulin, in this respect. This also included the chromatin-organizer protein SATB1, as an established regulator of HER expression in other tumor entities. In a panel of MET-amplified gastric carcinoma cell lines, cell growth under anchorage-dependent and independent conditions was studied upon inhibitor treatment or siRNA-mediated knockdown. Expression analyses were performed using RT-qPCR, FACS, and immunoblots. Signal transduction was monitored via antibody arrays and immunoblots. As expected, MET inhibition led to a growth arrest and inhibition of MAPK signaling. Strikingly, however, this was accompanied by a rapid and profound upregulation of the oncogenic receptor HER3. This finding was determined as functionally relevant, since HER3 activation by HRG led to partial MET inhibitor resistance, and MAPK/Akt signaling was even found enhanced upon HRG+MET inhibitor treatment compared to HRG alone. SATB1 was identified as mediator of HER3 upregulation. Concomitantly, SATB1 knockdown prevented upregulation of HER3, thus abrogating the HRG-promoted rescue from MET inhibition. Taken together, our results introduce the combined HER3/MET inhibition as strategy to overcome resistance towards MET inhibitors.

Expression of MAP9 in Epstein–Barr virus-associated gastric carcinoma

Epstein–Barr virus (EBV)-associated gastric carcinoma (GC) comprises approximately 9% of all cases of GC. EBV-associated GC (EBVaGC) has characteristic clinicopathological features for a favorable prognosis. Microtubule-associated protein 9 (MAP9) is a cell cycle-associated gene required for bipolar spindle assembly, mitosis progression, and cytokinesis. Nevertheless, to date, there have been no reports on MAP9 function in EBVaGC. In this study, we demonstrated that the mRNA and protein levels of MAP9 were up-regulated in EBV-positive gastric carcinoma cell lines. The positive rate of MAP9 expression in EBVaGC tissues was shown to be significantly higher than that in EBV-negative gastric carcinoma (EBVnGC) tissues. Additionally, the expression of MAP9 was partly increased in EBVnGC cell lines by interfering with DNA methyltransferase 1 (DNMT1) or treated with 5-aza-2′-deoxycytidine. Thus, EBV may regulate MAP9 expression by modifying the methylation of MAP9 CpG islands through DNMT1. By inhibiting the expression of MAP9 with small interfere sequence in the EBV-positive GC cell line GT38 and overexpressing MAP9 in the EBV-negative GC cell line AGS, we demonstrated that MAP9 inhibited the growth and induced apoptosis of EBVaGC cells significantly. In conclusion, our study demonstrated that EBV can up-regulate the expression of MAP9 in EBVaGC, and the methylation of MAP9 CpG islands influences this regulation. And MAP9 acts as a tumor suppressor in the development of EBVaGC.

Pyruvate Kinase M2 Knockdown Suppresses Migration, Invasion, and Epithelial-Mesenchymal Transition of Gastric Carcinoma via Hypoxia-Inducible Factor Alpha/B-Cell Lymphoma 6 Pathway.

Gastric carcinoma is a common malignant cancer. Pyruvate kinase M2 (PKM2) is highly expressed in cancers, including gastric carcinoma. However, its function and molecular mechanism in gastric carcinoma remains unclear. Here, we aimed to explore the function and the underlying mechanism of PKM2 on malignant phenotypes in gastric carcinoma. In this study, the mRNA levels and protein levels of PKM2 in gastric carcinoma cell lines and normal gastric mucosa epithelial cell lines were detected using quantitative real-time PCR and western blot, respectively. PKM2 was downregulated by siRNA transfection. HIF-1α or BCL-6 was upregulated by corresponding overexpression plasmid. Cell viability was detected using CCK-8 assay. Cell invasion and migration were determined using transwell assay. Higher expression of PKM2 was observed in human gastric carcinoma cell lines MKN-45 and SGC-7901 than in the normal gastric mucosa epithelial cell line GES-1. PKM2 knockdown suppressed cancer cell invasion and migration and inhibited the epithelial-mesenchymal transition (EMT) phenotype by inhibiting E-cadherin and promoting vimentin and N-cadherin expression. Also, we observed that PKM2 knockdown suppressed the hypoxia-inducible factor alpha (HIF-1α) and B-cell lymphoma 6 (BCL-6) signaling pathway. HIF-1α overexpression reversed the function of PKM2 silencing on cell invasion, migration, EMT, and BCL-6 expression. BCL-6 overexpression also reversed the function of PKM2 silencing on cell invasion, migration, and EMT but did not affect HIF-1α expression. Taken together, data from our study suggest that PKM2 knockdown impeded cell migration, invasion, and EMT of gastric carcinoma cells via the HIF-1α/BCL-6 pathway.

MiR-142 suppresses progression of gastric carcinoma via directly targeting LRP8

Recently, the role of miRNA-142 (miR-142) in tumor development has attracted extensive attention. The aim of this study was to investigate the impact of miR-142 and its potential target low-density lipoprotein receptor (LDLR)-related protein 8 (LRP8) on the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of gastric carcinoma (GC). Gene and protein expressions were detected using RT-qPCR and Western blotting, respectively. The biological behaviors of GC cell lines were determined by CCK-8, flow cytometry and Transwell assays, respectively. The interaction between miR-142 and LRP8 was confirmed with dual luciferase reporter assay. Xenograft nude mouse model was used to observe tumor growth. Here, miR-142 expression was markedly reduced in GC tissues and cells, and was negatively correlated with lymph node metastasis and poor prognosis in patients with GC. Stable miR-142 overexpression was sufficient to inhibit cell proliferation, migration and invasion in vitro and reduce tumor growth in vivo, accompanied by increased expression of the epithelial marker and reduced levels of mesenchymal markers. Mechanistically, the 3'-untranslated regions (3'-UTR) of LRP8 was a direct target of miR-142. Restoration of LRP8 attenuated the inhibitory effect of miR-142 on GC cells, whereas inhibition of LRP8 caused the opposite outcomes. In conclusion, our findings suggest that miR-142 plays a significant role in suppressing progression of GC by targeting LRP8, and miR-142 may be useful for the development of novel targeted therapies.

Formononetin exhibits anticancer activity in gastric carcinoma cell and regulating miR-542-5p.

Formononetin exhibits anti-neoplastic activities in specific types of cancers, such as colon carcinoma and breast cancer. Nevertheless, its role in suppressing gastric carcinoma (GC) growth and metastatic-associated phenotypes has not been fully understood. Here, we demonstrated that formononetin decreased the viability of GC cell line SGC-7901 and MGC-803. Furthermore, formononetin suppressed the migration and invasion abilities of GC cells. Consistent with the results in vitro, the anticancer effect of formononetin was verified using xenograft model. The expression of microRNA-542-5p (miR-542-5p), acted as an oncogene in many cancers, was identified to be upregulated in GC. Importantly, miR-542-5p might involve in formononetin exhibits anticancer activity in GC cells. Taken together, these results indicate that formononetin inhibits the growth and aggressiveness of GC cells in vitro and in vivo.

Allicin suppresses growth and metastasis of gastric carcinoma: the key role of microRNA-383-5p-mediated inhibition of ERBB4 signaling.

Allicin is a natural product suppressing the progression of gastric carcinoma (GC). In the current study, the mechanism underlying the anti-GC effect of allicin was explored by focusing on the role of miR-383-5p/ERBB4 signaling. Two GC cell lines were treated with allicin and the effects on viability, apoptosis, migration, invasion, and miR-383-5p/ERBB4 activity in the cells were assessed. The interaction between allicin and miR-383-5p was further explored by inhibiting the miR-383-5p level. Allicin suppressed cell viability and induced apoptosis in both GC cell lines. The compound also inhibited migration and invasion of GC cells, which was associated with the up-regulation miR-383-5p and down-regulation of ERBB4. The inhibition of miR-383-5p by specific inhibitor blocked the anti-GC effect of allicin. Our results demonstrated that allicin contributed to the suppressed growth and metastasis potentials in GC cell lines. The effect was accompanied by an increased level of miR-383-5p and subsequent inhibition of ERBB4.

Ursolic Acid Protects Against Proliferation and Inflammatory Response in LPS-Treated Gastric Tumour Model and Cells by Inhibiting NLRP3 Inflammasome Activation.

BackgroundInflammation is considered as one of the hallmarks of cancer development and progression. Ursolic acid (UA) showed strong effects as an anti-inflammatory and antioxidant. However, the anti-cancer effects of ursolic acid require further study.MethodsThis study aimed to investigate the role of ursolic acid in a lipopolysaccharide (LPS)-treated gastric tumour mouse model and in a human gastric carcinoma cell line (BGC-823 cells). This study also aimed to confirm whether ursolic acid can protect against proliferation and the inflammatory response induced by LPS, by inhibiting the activation of the NLRP3 inflammasome via the NF-κB pathway.ResultsThe present study demonstrated that ursolic acid significantly attenuated LPS-treated proliferation in a gastric tumour mouse model and the human gastric carcinoma BGC-823 cell line, reduced the expression of the NLRP3 inflammasome and suppressed the release of pro-inflammatory cytokines. In addition, ursolic acid inhibited the LPS-induced activation of NF-κB. Furthermore, the NF-κB pathway regulated the activation of the NLRP3 inflammasome.ConclusionIn conclusion, these results demonstrated that ursolic acid could suppress proliferation and the inflammatory response in an LPS-induced mouse gastric tumour model and human BGC-823 cells by inhibiting the activation of the NLRP3 inflammasome via the NF-κB pathway. This indicates that ursolic acid can be a potential therapeutic agent for the treatment of gastric cancer.

Niclosamide exerts anti-tumor activity through generation of reactive oxygen species and by suppression of Wnt/ β-catenin signaling axis in HGC-27, MKN-74 human gastric cancer cells

Introduction Gastric carcinoma (GC) remains a therapeutic challenge despite having many potent drugs to treat. Various studies emphasized the role of dysregulated Wnt/β-catenin pathway in cancer. In the present study, we examined the anti-cancer effect of Niclosamide and its effect on the dysregulated β-catenin pathway in human gastric carcinoma cell lines. Methods Cytotoxicity of compound to gastric cancer cell line was assessed by MTT cell viability assay, cell cycle analysis, and apoptosis assay was done using standard kits of Muse™ Cell Analyser. Reactive oxygen species (ROS) generation and mitochondrial membrane potential were analyzed by 2′,7′-Dichlorodihydrofluorescein diacetate (DCFDA) and tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining respectively. Protein expression studies were carried out by standard western blotting protocols. Results Niclosamide treatment resulted in a dose-dependent inhibition of viability of the gastric carcinoma cell-lines induced cell cycle arrest in the G0/G1 phase and strongly induced apoptosis in a concentration-dependent manner by downregulating Cyclin-D1 and CDK4 levels, critical proteins required for G1-S phase progression. DCFDA and JC-1 staining results indicated that Niclosamide enhanced intracellular ROS generation and disrupted mitochondrial membrane potential. Furthermore, niclosamide treatment decreased the expression of NF-KB, Bcl-2 and increased the expression of Bax protein. Niclosamide treatment significantly decreased the β-catenin mediated transcriptional activity and down-regulated β-catenin levels and its downstream proteins cyclinD1, CDK-4, and c-myc expression and also impeded Akt phosphorylation, a common internode in the Wnt and Akt/mTOR signaling in HGC-27 cells. Conclusion This study demonstrated that Niclosamide might become a promising therapeutic agent for the management of gastric cancer and further warrants its clinical trials in gastric cancer patients.

Sex Chromosomes Are Severely Disrupted in Gastric Cancer Cell Lines.

Sex has not received enough attention as an important biological variable in basic research, even though the sex of cells often affects cell proliferation, differentiation, apoptosis, and response to stimulation. Knowing and considering the sex of cells used in basic research is essential as preclinical and clinical studies are planned based on basic research results. Cell lines derived from tumor have been widely used for proof-of-concept experiments. However, cell lines may have limitations in testing the effect of sex on cell level, as chromosomal abnormality is the single most characteristic feature of tumor. To examine the status of sex chromosomes in a cell line, 12 commercially available gastric carcinoma (GC) cell lines were analyzed using several different methods. Loss of Y chromosome (LOY) accompanied with X chromosome duplication was found in three (SNU-484, KATO III, and MKN-1) out of the six male-derived cell lines, while one cell line (SNU-638) showed at least partial deletion in the Y chromosome. Two (SNU-5 and MKN-28) out of six female-derived cell lines showed a loss of one X chromosome, while SNU-620 gained one extra copy of the X chromosome, resulting in an XXX karyotype. We found that simple polymerase chain reaction (PCR)-based sex determination gives a clue for LOY for male-derived cells, but it does not provide detailed information for the gain or loss of the X chromosome. Our results suggest that carefully examining the sex chromosome status of cell lines is necessary before using them to test the effect of sex on cell level.