Anti-proliferation effects of interferon-gamma on gastric cancer cells.

IFN-gamma plays an indirect anti-cancer role through the immune system but may have direct negative effects on cancer cells. It regulates the viability of gastric cancer cells, so we examined whether it affects their proliferation and how that might be brought about. We exposed AGS, HGC-27 and GES-1 gastric cancer cell lines to IFN-gamma and found significantly reduced colony formation ability. Flow cytometry revealed no effect of IFN-gamma on apoptosis of cell lines and no effect on cell aging as assessed by beta-gal staining. Microarray assay revealed that IFN-gamma changed the mRNA expression of genes related to the cell cycle and cell proliferation and migration, as well as chemokines and chemokine receptors, and immunity-related genes. Finally, flow cytometry revealed that IFN-gamma arrested the cells in the G1/S phase. IFN-gamma may slow proliferation of some gastric cancer cells by affecting the cell cycle to play a negative role in the development of gastric cancer.