Abstract
We will report a targeting and an anti-cancer effect of a lipid vesicle, to which Euchuma Serra Agglutinin (ESA) immobilized, to human colon cancer cell (Colo201) in mouse xenopathic model. The lipid vesicles were mainly composed of Span80 (sorbitan monooleate). First, the specific binding between the lipid vesicle and the cancer cell was studied for the application of the vesicle to DDS. It was preliminary confirmed that the vesicle flew smoothly in superior artery of a rabbit. As a targeting ligand (combined with the vesicle) at a Colo201, Euchuma Serra Agglutinin (ESA) was chosen. The ESA is a new lectin derived from a marine red alga and specifically combines with mannose-rich carbohydrate-chain, which often exists on the surface of cancer cells abundantly. ESA was found to specifically combine with many cancer cells, especially to colon adenocarcinoma (Colo201) and induce an apoptosis to the cancer cell. Secondly, the in vivo experiments toward to colon cancer therapy were carried out administrating the ESA-immobilized vesicles into nude mice in which human colon cancer-cell Colo201 had been implanted. Preliminary autoradiogram experiments showed the free ESA selectively accumulated in the tumor of the mice. Then, we prepared either ESA-immobilized vesicle or the vesicle entrapping anti-tumor drug (Taxotere) for using colon-cancer xenopathic model in nude mouse. Autoradiograms also showed the ESA-immobilized vesicles were specifically accumulated into the tumor rather than the other organ. The most effective anti-tumor effect was observed in using the ESA-immobilized vesicle entrapping Taxotere.
