In peritoneal dissemination and subcutaneous tumor models, the SART3/CD40L+GM-CSF-loaded polyplex micelles were predominantly distributed to DCs in the lymph nodes, spleen, and liver after i.p. administration, inhibited the growth and metastasis of subcutaneous tumors, and prolonged the survival of mice with peritoneal dissemination of cancer cells. The gene discussed is CD40LG; the disease is cancer.