Assessment of apoptosis mediated cell death induction by gemcitabine conjugated gelatin nanoparticles. (a) mRNA expression profile for transcription factors in the apoptotic pathway (n = 6, *p < 0.05; **p < 0.01; ***p < 0.001). (b) Western blot analysis for cleaved PARP, cleaved caspase 3 and β-actin protein expression in treated tumors. (c) TUNEL stained images of treated tumors indicating DNA fragmentation (brown stain). All images were acquired at 20× with scale bar of 50 μm.