Effect of antiangiogenic therapy on luciferase activity in a cytomegalovirus- or HSP70promoter-transfected M21 tumor model

We investigated the effect of targeted gene therapy on heat shock protein 70 expression (Hsp7O) and protein production (HSP7O) in a melanoma tumor model (M21; M21-L). M21 and M21-L cells transfected with a plasmid containing the Hsp7O (Hspa1b) or the cytomegalovirus (CMV) promoter and the luciferase reporter gene were injected into mice; the resulting tumors grew to a size of 650 mm3. Mice were intravenously treated with an Arg-Gly-Asp peptide-nanoparticle/Raf-1 kinase inhibitor protein complex [RGD-NP/RAF(-)] or with a nanoparticle control. Bioluminescence imaging was performed at 12, 24, 48, and 72 h after the treatment cycle. Western blot analysis of HSP7O protein was performed to monitor protein expression. In accordance with bEotuminescent maging, western blot analysis showed a peak n HSP7O production at 24 h after the injection of the RGD-NP/RAF(-) complex in the M21 tumors; however, no HSP7O protein induction was seen in the M21-L tumors. Thus, targeted antiangiogenic therapy can induce Hsp7O expression and HSP7O protein in melanoma tumors.