To achieve tissue specificity, we previously used JCPyV VLPs to deliver tissue-specific promoters to specifically express a gene of interest in a particular cell; these promoters included the lung cancer-specific SPB promoter17,18, prostate cancer-specific PSA promoter19, and MUC1 promoter, which is overexpressed in bladder cancer16. The gene discussed is SFTPB; the disease is prostate carcinoma.