Paclitaxel encapsulated in cationic lipid complexes (MBT-0206) impairs functional tumor vascular properties as detected by dynamic contrast enhanced magnetic resonance imaging.

Cationic lipid complexes have been shown to be bound and internalized selectively by angiogenic tumor endothelial cells after intravenous injection. Based on this phenomenon, the chemotherapeutic agent paclitaxel was encapsulated into these lipid complexes providing a vascular targeting agent (MBT-0206). As non-invasive imaging techniques are of critical importance for optimizing antivascular cancer treatment in the clinic, we have evaluated the antivascular effects of MBT-0206 in the A-MEL-3 solid tumor model using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI).Twenty-four hours after 3 intravenous applications of MBT-0206, tumors of treated animals demonstrated a significant decrease of intratumoral blood volume and an increase of vascular permeability in comparison to size matched control tumors. In contrast, animals treated with conventional paclitaxel given as Taxol® at equal drug dose did not show any significant differences in vascular parameters acquired by DCE-MRI in comparison to...