Previous reports highlighted the use of different promoters for breast cancer virotherapy such as hTERT [35,37,62,68,69,70,71], MDR [72], mucin-1 (MUC1) [51,73], hypoxia-responsive [71,74,75], estrogen-responsive [61,71,75], surviving [76], L-plastin [77], and Cyclooxygenase-2 (Cox-2) [72]. This evidence concerns the gene MUC1 and breast cancer.