Project description:The first is transcriptional profiling of siRNA-mediated knockdown of IQGAP3 in human gastric cancer cell line AGS, NUGC3, and Hs746T comparing with non-target siRNA transfected AGS, NUGC3, and Hs746T as a control. The aim of this experiment was to evaluate the functions of IQGAP3 in three different gastric cancer cell lines in vitro. The second is bulk RNA-sequence from subcutaneous tumors, which were injected NUGC3 shIQGAP3 knockdown cells and NUGC shContorl cells into immunodeficient mice (NSG mice). The aim is to evaluate the difference of transcriptional profiling in human cancer cells and mouse stromal cells of shIQGAP3 knockdown tumors compared to shContorol tumors.
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.