Project description:Gastric cancer is a highly immunogenic malignancy. Immune tolerance facilitated by myeloid-derived suppressor cells (MDSCs) has been implicated in gastric cancer resistance mechanisms. The potential role of APE1 in regulating gastric cancer metastasis by targeting MDSCs remains uncertain. In this study, the plasmid Plxpsp-mGM-CSF was used to induce high expression of granulocyte-macrophage colony-stimulating factor (GM-CSF) in GES-1 cells. For tumor transplantation experiments, AGS, AGS+GM-CSF and AGS+GM-CSF-siAPE1 cell lines were established by transfection, followed by subcutaneous implantation of tumor cells. MDSCs, Treg cells, IgG, CD3 and CD8 levels were assessed. Transfection with siAPE1 significantly inhibited tumor growth compared to the AGS+GM-CSF group. APE1 gene knockdown modulated the immune system in gastric cancer mice, characterized by a decrease in MDSCs and an increase in Treg cells, IgG, CD3 and CD8. In addition, APE1 gene knockdown resulted in decreased levels of pro-MDSC cytokines (HGF, CCL5, IL-6, CCL12). Furthermore, APE1 gene knockdown inhibited proliferation, migration and invasion of AGS and MKN45 cells. AGS-GM-CSF cell transplantation increased MDSC levels and accelerated tumor growth, whereas APE1 knockdown reduced MDSC levels, inhibited tumor growth and attenuated inflammatory infiltration in gastric cancer tissues.
Project description:We performed RNA-Seq to confirm the changes in expression of genes in the relevant pathway in human gastric cancer cells (AGS cells) and AGS cells cocultured with macrophages (RAW264.7 cells). In the gene ontology enrichment analysis of the 160 genes that were increased in AGS cells cocultured with RAW264.7 cells, pathways related to immune response, cell adhesion, and cytokine response were enriched.
Project description:In order to better understand the relationship between NOTCH1 gene and immunity in gastric adenocarcinoma cells, we performed the silent interference of NOTCH1 gene on three gastric adenocarcinoma cell lines AGS, MKN-45 and MGC-803. We extracted the total RNA from the interfered and untreated blank control cells, and performed lncRNA library construction and sequencing. The results of bioinformatics analysis showed that the silencing of NOTCH1 gene in gastric adenocarcinoma cells activated several immune-related signal transduction pathways, including T cell receptors, chemokines, JAK-STAT, Toll-like receptors, ECM receptors and other signals. Conduction pathway. These results confirm that NOTCH1 may down-regulate the immune response of gastric adenocarcinoma.
Project description:Ornithogalum is one of the therapeutic formulation used in homeopathic treatments. It is specifically used in the treatment for gastric and duodenal ulcerations. Towards understanding the anticancer mechanism, we investigated the genome-wide mRNA changes upon treating AGS Gastric Cancer cells with Ornithogalum. We observed that totally 707 genes were significantly regulated upon Ornithogalum Treatment, among them 246 genes were upregulated and 461 genes were downregulated. The results provide insight into molecular implication and gene level expression of AGS upon treatment with Ornithogalum. Total RNA was isolated from AGS gastric cancer cells treated with 0.01% of ornithogalum and ethanol control and profiled using Affymetrix Human Gene 1.0 ST Array (HuGene-1_0-st).
Project description:Stable knockdown of NET1, a RhoGEF, was achieved in AGS Gastric Cancer cells. This gene is known to be overexpressed in the disease. Knockdown was achieved using lentiviral shRNA particles. Gene expression was compared between knockdown and scrambled shRNA treated control cells. Cells were treated with and without LPA, a known activator of RhoA.
Project description:Gastric cancer is one of the most common cancers worldwide. Epstein-Barr virus-associated gastric cancer accounts for approximately 10% of all gastric cancers. EBV expresses its own proteins and miRNAs (BART miRNAs) and regulates host gene expression. In this study, we examined the effect of EBV infection on host mRNA expression. Differential gene expression was analyzed between EBV-negative human gastric cancer cell line AGS and EBV-positive human gastric cancer cell line AGS-EBV.
Project description:Background Mitogen-activated protein kinase 1 (MAPK1) has independent functions of phosphorylating histones as a kinase and directly binding the promoter regions of genes to regulate gene expression as a transcription factor. Previous studies identified elevated expression of MAPK1 in human gastric cancer, which is associated with its role as a kinase, facilitating gastric cancer cell migration and invasion. However, being a transcription factor, how MAPK1 binds its target genes and whether it modulated related gene expressions in gastric cancer remains unclear. Results Here, we integrated biochemical assays (protein interactions and chromatin immunoprecipitation (ChIP)), cellular analysis assays (cell proliferation and migration), RNA sequencing, ChIP sequencing, and clinical analysis to investigate the potential genomic recognition patterns of MAPK1 in a human gastric adenocarcinoma cell-line (AGS) and to uncover its regulatory effect on gastric cancer progression. We confirmed that MAPK1 promotes AGS cells invasion and migration by regulating the target genes in controversial directions, up-regulating seven target genes (KRT13, KRT6A, KRT81, MYH15, STARD4, SYTL4, and TMEM267) and down-regulating one gene (FGG). Among them, five genes (FGG, MYH15, STARD4, SYTL4, and TMEM267) were first associated with cancer procession, while the other three (KRT81, KRT6A, and KRT13) have been previously confirmed to be related to cancer metastasis and migration. Conclusion Our data showed that MAPK1 binds to the promoter regions of these target genes to control their transcription, hence encouraging AGS cell motility and invasion. Our research broadened the understanding of the regulatory roles of MAPK1, enriched the knowledge of transcription factors, and provided novel candidates for cancer therapeutics.