STAT3 and neoplasm: Han et al. (2009) modified an oncolytic adenovirus to inhibit STAT3 by inserting a 770 bp antisense fragment of STAT3 into the ADP locus of Ad5/dE1A, previously generated with a deletion of amino acids 121–129 in E1A. They evaluated the resulting virus, M4, for its ability to inhibit metastasis in an orthotopic model of gastric cancer established using explanted MKN-45 xenograft tumor fragments (Huang et al., 2008).