Enhanced Efficiency of Thermally Targeted Taxanes Delivery in a Human Xenograft Model of Gastric Cancer

Since successful chemotherapy with taxanes requires an improvement in their therapeutic index, especially by the reduction in unwanted systemic toxicity of either drug or adjuvants, we have investigated and are reporting results from an investigation of the use of a novel polymeric thermosensitive micellar delivery system for docetaxel and paclitaxel. Here we reported a novel metastable thermosensitive polymeric micelle for docetaxel and paclitaxel delivery [poly(N-isopropylacrylamide-co-acrylamide)-b-poly(DL-lactide), Poly(IPAAm-co-AAm)-b-PDLLA]. Previous in vitro efficacy studies indicated that, with hyperthermia, docetaxel-loaded micelles showed stronger cytotoxicity to different tumor cell lines than conventional docetaxel formulation while exhibiting slighter toxicity to normal cells. Present in vivo studies indicated that at the same dose level of docetaxel (paclitaxel), hyperthermia greatly enhanced the antitumor effect of micellar docetaxel (paclitaxel) in human gastric BGC mouse xenograft model by showing an extraordinary tumor volume and weight growth percentage inhibition of more than 80%. Meanwhile, acute toxicity tests features the lower LD50 of the combination of hyperthermia and micellar docetaxel (paclitaxel) compared to that of the control group. The present results suggest that poly(IPAAm-co-AAm)-b-PDLLA micelles could be a clinically useful chemotherapeutic formulation and merit further research to evaluate the feasibility of clinical application.