As a next step, to reduce potential non-tumor side effects by enhancing tumor-selective NIS expression, we studied the potential use of the tumor stroma-induced CCL5 (RANTES) gene promoter, which allowed a robust tumoral iodine accumulation in experimental tumors in mice leading to significantly reduced tumor growth and prolonged survival of the experimental animals after 131I and 188Re treatment 35. Here, CCL5 is linked to neoplasm.