SMAD-NIS-MSCs induced an 123I uptake of 6.8 ± 0.8% ID/g as visualized by [123I]NaI-scintigraphy and a tumor-absorbed dose of 28.2 mGy/MBq for 131I in a s.c. HuH7 xenograft mouse model. Here, SLC5A5 is linked to neoplasm.