Elevated interstitial fluid pressure (IFP) in a tumor is a barrier to tumor accumulation of systemic delivery of nanocarriers. In this study, we investigated whether intravenous injection of type I collagenase (collagenase-1) reduced IFP in tumors and increased the accumulation and gene expression of cationic liposome/plasmid DNA complex (lipoplex) in tumors after intravenous injection into mice bearing mouse lung carcinoma LLC tumors. Collagenase-1 reduced the amount of type I collagen in the tumor, and significantly decreased IFP by 65% at 1h after injection. Therefore, collagenase-1 induced 1.5-fold higher accumulation and 2-fold higher gene expression of lipoplex in tumors after intravenous injection. These findings indicated that intravenous injection of collagenase-1 improved the accumulation of lipoplex by decreasing IFP in tumors. These results support the potential use of collagen digestion as a strategy to improve systemic gene delivery into tumors.
Collagenasi, suitable for release of rat epididymal adipocytes and hepatocytes (for methodology see Type II and Type IV), Type VIII, 0.5-5.0 FALGPA units/mg solid, ≥125 CDU/mg solid
Collagenasi, 0.2 μm filtered, suitable for release of physiologically active rat hepatocytes, Type IV-S, 0.5-5.0 FALGPA units/mg solid, ≥125 CDU/mg solid
Collagenasi, 0.2 μm filtered, suitable for release of physiologically active rat epididymal adipocytes, Type II-S, 0.5-5.0 FALGPA units/mg solid, ≥125 CDU/mg solid