Regulation of Growth of Gastric Cancer Cells and Sensitivity to Cisplatin by Modulation of DNA Binding Inhibitor or Differentiation Protein Expression

Objective: To determine the role of DNA-binding inhibitors and differentiation protein in the regulation of gastric-cancer cell growth and sensitivity to cisplatin. Methods: An ID1 protein (ID1)-expression vector was constructed for gene transfection. Western blot, methylthiazol tetrazolium (MTT) assay, and flow cytometric testing were used in gastric-cancer cells to assess ID1 expression, cell viability, and distribution of cell-cycle stages, respectively. Results: ID1 complementary DNA (cDNA) and small hairpin RNA (shRNA) effectively induced and reduced ID1 expression, respectively, in gastric cancer cells. Knockdown of ID1 expression suppressed tumor-cell viability and reduced colony formation, whereas overexpression of ID1 increased colony formation. Further, we found that ID1 overexpression antagonized the effects of cisplatin-induced apoptosis in gastric-cancer cells. Conclusion: The data from the current study demonstrate the role of ID1 in inducing gastric cancer-cell proliferation and colony formation, which suggests that ID1 may be a novel target for gastric-cancer treatment.