RGS1 serves as an antitumor target to inhibit proliferation of NICN87-DR cells and tumor growth in the gastric cancer mouse model.

Gastric cancer is becoming the 4th leading cause of cancer-associated death worldwide. The purpose of this study was to investigate the role of RGS1 in gastric cancer in vitro and in vivo. Proliferation, migration, invasion, and colony formation of NCIN87 cells and drug-resistant NCIN87 cells (NCIN87-DR) were determined. Cell apoptosis and cell cycle were examined using a flow cytometry assay. RGS1 gene knock-down vector (pLVshshRGS1) and Xenograft tumor mouse model was generated. RGS1 and epithelial-mesenchymal transition (EMT) associated markers, including E-cadherin (E-cad), N-cadherin (N-cad), Slug, and Vimentin were detected using a western blotting assay. Tumor size of Xenograft tumor mouse was measured and Ki67 expression was detected using the immunohistochemical assay. NCIN87-DR cells demonstrated significantly lower proliferation, migration, and invasion compared to those of NCIN87 cells (p < 0.05). NCIN87-DR cells showed obvious early apoptosis and displayed obvious alterations for the cell cycle. NCIN87-DR cells exhibited predominantly higher RGS1 expression than that in NCIN87 cells (p < 0.01). E-cad expression was markedly decreased (p < 0.01) and N-cad (p < 0.05), Slug (p < 0.01), Vimentin (p < 0.05) expressions were significantly increased in NCIN87-DR cells than those in NCIN87 cells. RGS1 gene silence remarkably reduced NCIN87-DR proliferation compared to that in NCIN87-DR cells without treatment (p < 0.01). RGS1 gene-silenced NCIN87-DR cell immunization predominantly inhibited tumor growth in Xenograft tumor mouse than that without RGS1 silence (p < 0.05). RGS1 gene-silenced NCIN87-DR cell immunization significantly downregulated Ki67 expression in tumor tissues compared with that without RGS1 silence. In conclusion, RGS1 gene silence reduced the proliferation of NCIN87-DR cells in vitro and inhibited tumor growth in vivo. Therefore, RGS1 served as an antitumor target for the gastric cancer treatment.