In contrast to the suppression of stably expressed LUC mRNA in 4T1-Luc tumors, we recently found that Chol-DsiRNA polyplexes targeting STAT3, a more widely expressed and therapeutically relevant mRNA, maintain suppression of STAT3 mRNA in primary 4T1 breast tumors less than 24 h after a single lower dose of Chol-DsiSTAT3 [0.5 mg/kg] that does not saturate the primary tumor [2]. This evidence concerns the gene STAT3 and breast neoplasm.