Abstract: Objective: To examine the effect of sodium selenite on growth of SGC-7901 cells. Methods: The growth curve of SGC-7901 cells was measured by using cell culture and SRB experiment; effects of sodium selenite on SGC-7901 cell colony- forming and cell mitotic index were examined by using the relative tests; effect of sodium selenite on SGC-7901 cell growth cycle was measured by using flow cytometry; and sodium selenite-induced SGC-7901 cell apoptosis was examined by electron microscope, TUNEL staining and flow cytometry. Results: In the curve sodium selenite significantly inhibited respectively the SGC-7901 cell growth, colony-forming and mitotic index dose dependently. Flow cytometry detection showed that, after 24 hours, sodium selenite reduced the percentage of G1 phase cells but increased the percentage of S phase cells in cell cycle (p< 0.05 compared with control group). Electron microscope detection showed nucleus pycnosis, and crescent-shaped chromatic agglutination stiching closed to karyotheca with karyotheca distortion. DNA histogram showed a typical apoptosis peak as hyodiplod. TUNEL staining showed that apoptosis index was between 10.4% and 33.4%. Conclusion: Sodium selenite had an inhibitory effect on SGC-7901 cell growth with dose-effect relationship. The inhibition of S phase cell proliferation and induction of cell apoptosis might underlie the mechanism of the inhibitory effect of sodium selenite on SGC-7901 cell growth.

Key words: SGC-7901 cell, sodium selenite, mitotic index, cell cycle, cell apoptosis