These data show the superior activity of the MYC/KRAS chimeric siRNA formulation, which is likely more effective than coadministration of each single-targeting siRNA because of (a) its consistent uptake and targeting of both transcripts into each tumor cell (a pattern reflected in initial in vitro experiments; Figure 6B), (b) its improved potency via the additional 5′-dT overhangs (Figure 3C), and (c) its increased metabolic stability within the tumor (Figure 7B and Figure 8F). Here, KRAS is linked to neoplasm.