Abstract:[Objective]To explore the effects of 5‐Aza‐2‐deoxycytidine (5‐Aza) on apoptosis ,autophagy and in‐sulin signal pathway in GC‐7901 cell line .[Methods]GC‐7901 cells were treated with 5 ,10 and 20μmol/L of 5‐Aza for 3 days .The expressions of autophagy‐related proteins LC3‐Ⅱ and LC3‐Ⅰwere detected by Western blot .And 10μmol/L5‐Aza was used for intervening GC‐7901 .Two groups of control and 5‐Aza were assigned .The expressions of insulin signaling axis associated proteins IGF‐1R and p‐IGF‐1R were detected by Western blot .And the expressions of IGF‐1R downstream signaling pathway related proteins PI3K ,p‐PI3K ,mTOR ,p‐mTOR were measured .Annexin V‐PI flow cytometry was used for detecting apoptotic cells .[Results]5‐Aza dose‐dependently decreased the level of LC3‐Ⅰand increased the level of LC3‐Ⅱ .And a significant increase in LC3‐Ⅱ/LC3‐Ⅰratio suggested that demethylating agent could significantly increase autophagy in gastric cancer cells .Cell autophagy and apoptosis could be induced by 5‐Aza .The expressions of phosphorylated insulin signaling pathway related proteins ,such as p‐IGF‐1R ,p‐PI3K and p‐mTOR ,significantly decreased .But it had no effect on total protein IGF‐1R ,PI3K or mTOR .[Conclusion]5‐Aza can induce cell autophagy and apoptosis and decrease the levels of phospho‐IGF‐1R , phospho‐PI3K and phospho‐mTOR proteins .However ,there is no effect on the total protein levels .