A stent film of paclitaxel presenting extreme accumulation of paclitaxel in tumor tissue and excellent antitumor efficacy after implantation beneath the subcutaneous tumor xenograft in mice.

Anti-tumor drug/stent combinations play a dual role of stent and local chemotherapy to cancer. Herein, a series of paclitaxel (PTX) loaded polylactic acid (PLA) stent films were studied on drug release characteristics and in vivo antitumor effects. The film was implanted beneath and released drug towards the subcutaneous PC-3 tumor xenograft in mice, which consisted of a PTX-loaded layer and a drug-free backing layer. The concentrations of PTX were 103-104 times higher than those in normal 20 tissue or organs in 26 days after implantation of the 50% PTX/20% PEG-loaded film, indicating an extreme accumulation of PTX in tumor tissue. The tumor volumes kept unchanged for the initial 10 days after implantation of the PTX-loaded films and then increased slightly, implying tumor growth was remarkably inhibited. Moreover, the results showed that the drug release can be effectively modulated by addition of PEG in the drug-loaded layer, present an unidirectional way by adding a backing layer, and the drug films could arrest PC-3 prostate cancer cells in G2/M phase and induce apoptosis after 300 days of drug release. With the advantages of prolonged drug release and long-term effectiveness, the films have great potential for anti-tumor treatment by local administration.