SLC5A5 and neoplasm: 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.