A key finding of the present study is that both Chol-siSTAT3 polyplexes and Chol-DsiSTAT3 polyplexes maintain the suppression of STAT3 mRNA in primary 4T1 breast tumors less than 24 h after IV administration of a single equimolar dose [0.50 mg Chol-DsiSTAT3/kg or 0.41 mg Chol-siSTAT3/kg] (Figure 3B). Here, STAT3 is linked to breast neoplasm.