This study evaluates the therapeutic effects of autologous dendritic cells co-cultured with cytokine-induced killer cells (DC-CIK) combined with S-1 ((Tegafur, Gimeracil, and Oteracil Potassium) and oxaliplatin adjuvant chemotherapy in locally advanced unresectable or metastaticgastric cancer. Half of participants will receive DC-CIK combined with S-1 and oxaliplatin adjuvant chemotherapy,while the other half will receive S-1 and oxaliplatin adjuvant chemotherapy served as controls.