(A) Mice bearing subcutaneous pancreatic (CAPAN-2) tumors were injected once a week for 6 weeks with saline, Dox (2mg/kg) alone and Dox followed 24h later by MN-siBIRC5 (10mg/kg Fe; 250nmoles/kg siBIRC5). The mean ± standard error of the mean (SEM) of the relative tumor volumes is shown at the indicated time points (n = 3, two-tailed Student t-test; P<0.05). Tumor growth was significantly inhibited in the Dox-MN-siBIRC5 treatment group relative to the other groups. (B) Detection of caspase-3 activity in tumor lysates. Excised tumors were analyzed by caspase-3 enzyme assay. Data are represented as ± S.D. (n=8, two-tailed Student’s t-test, **P<0.0005). Caspase-3 activation was significantly higher in the Dox-MN-siBIRC5 treatment group relative to PBS. (C) Detection of cleaved PARP in tumor tissue sections by immunofluorescence. Nuclei stained with (DAPI, Blue) and cleaved PARP immunostained (Texas red, Red) were visualized by fluorescence microscopy. PARP cleavage was most prominent in the Dox-MN-siBIRC5 treatment group.