Imiquimod inhibits the growth of SGC‑7901 cells in vitro through induction of autophagy and apoptosis.

Imiquimod, the most prominent Toll‑like receptor 7 agonist, has direct anti‑tumor activity and can induce autophagy and apoptosis in various types of human cancer. The aim of the present study was to examine the anti‑tumor effects of imiquimod and their underlying mechanisms in SGC‑7901 cells. Imiquimod exerted an inhibitory effect on cell proliferation in a dose‑ and time‑dependent manner as indicated by an MTT assay. Imiquimod induced autophagy as well as apoptosis, while simultaneous treatment with 3‑methyladenine (3-MA), an autophagy inhibitor, decreased the toxicity of imiquimod. Furthermore, blocking of autophagy by 3‑MA exerted an inhibitory effect on imiquimod-induced apoptosis, which indicated that autophagy can function as a mechanism which, upon activation, directly leads to apoptosis and cell death of SGC‑7901 cells. The results of the present study suggested that imiquimod has potent direct activity against gastric cancer cells by inducing autophagy and apoptosis.