In former studies, we tested polyplexes with an EGFR-specific targeting peptide (GE11) as NIS gene delivery vehicles in a subcutaneous HuH7 xenograft tumor model [15] as well as in orthotopic pancreatic ductal adenocarcinoma [29], which resulted in high tumor-specific NIS-mediated iodide accumulation. Here, SLC5A5 is linked to neoplasm.