Abstract: 【Abstract】: Objective: Doxycycline on gastric cancer cell line BGC-823 proliferation and Notch1,MMP-9 expression, in order to provide a new new anticancer drugs. Method: Respectively 0, 5, 10, 20, 40 μg/mL final concentration of doxycycline effects on human gastric cancer cell line BGC-823.Cell proliferation was detected was detected by MTT degree; flow cytometry cell cycle distribution; Western Blot detection Notch1, MMP-9 protein expression. Results: Doxycycline can inhibit the proliferation of human gastric cancer cells line BGC-823, and the effect of drug dose and time-dependent（P＜0.01）; doxycycline alter gastric cancer cell line BGC-823 cycle distribution, with increasing concentration, S the proportion of lower phase（P＜0.01）; as the concentration increase, Notch1 expression enhancement, MMP-9 expression decreased （P＜0.01）. Conclusion: Doxycyclinecan inhibit gastric cancer cell line BGC-823 proliferation, Notch1 up as one of the possible mechanisms.

Key words: gastric cancer cells, doxycycline, Notch1, MMP-9, cell proliferation, cell cycle