Compared to the delivery of non-targeting double-stranded RNA of similar length and structure, ectopic miR-155 induced silencing of multiple immunosuppressive mediators, including Tgfb1 and Cd200. As expected, miR-155 also targeted crucial transcription factors involved in aberrant myeloid differentiation in tumor-bearing hosts, including Cepb/β and Socs1. Most importantly, miR-155 activity down-regulated Stat3 and, interestingly, Satb1, a master genomic organizer (37, 41). This evidence concerns the gene TGFB1 and neoplasm.