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.

Inclusion Criteria:

1. Age>18y;
2. ECOG physical status 0-1;
3. The histologic diagnosis of stomach/gastroesophageal junction adenocarcinoma;
4. According to the RECIST 1.1 standard with measurable or evaluable lesion;
5. Accept swallow oral drug;
6. WBC≧4.0×10^9/L;ALC≧0.8×10^9/L;ANC≧1.5×10^9/L;PLT≧100×10^9/L;ALT,AST≦2.5 times of the normal limit;ALP≦2.5 times of the normal limit;TBIL﹤1.5 times of the normal limit;SCr﹤1 times of the normal limit;ALB≧30g/L;
7. The expected survival time of more than 3 months;
8. good compliance;
9. Provide written informed consent.

Exclusion Criteria:

1. Vital organs (heart,liver,kidney) function is serious dysfunction;
2. Patients received organ transplantation;
3. Patients with other malignant tumors or have occurred brain metastasis;
4. Patients with history of autoimmune disease;
5. Patients in pregnancy or breast-feeding period(women of child-bearing age need to check pregnancy test);
6. Patients with acute infection disease or in chronic active stage;
7. Patients with clear history of drug allergy or belong to allergic constitution;
8. Patients received chemotherapy,radiation therapy, immunosuppressive drugs (cyclosporine A,etc.) or other immune treatment in 4 weeks;
9. Patients received other clinical trials in 4 weeks.