To study the effect of AGTR1 on tumor growth and lymph node metastasis, we prepared two types of orthotopically implanted tumors, Balb/c-nu nude mice bearing MDA-MB-231 tumors and Balb/c mice bearing 4T1 tumors, and chose losartan, an AGTR1 antagonist, to block AGTR1. The gene discussed is AGTR1; the disease is neoplasm.