Bauhinia purprea agglutinin‐modified liposomes for human prostate cancer treatment

摘要

Bauhinia purprea agglutinin (BPA) is a well‐known lectin that recognizes galactosyl glycoproteins and glycolipids. In the present study, we firstly found that BPA bound to human prostate cancer specimens but not to normal prostate ones. Therefore, we sought to develop BPA‐PEG‐modified liposomes (BPA‐PEG‐LP) encapsulating anticancer drugs for the treatment of prostate cancer. We examined the tumor targetability of BPA‐PEG‐LP with human prostate cancer DU145 cells, and observed that fluorescently labeled BPA‐PEG‐LP dominantly associated with the cells via the interaction between liposome‐surface BPA and cell‐surface galactosyl molecules. We also observed that BPA‐ style="fixed-case">PEG‐ style="fixed-case">LP accumulated in the prostate cancer tissue after the i.v. injection to style="fixed-case">DU145 solid cancer‐bearing mice, and strongly bound to the cancer cells. In a therapeutic study, style="fixed-case">DU145 solid cancer‐bearing mice were i.v. injected thrice with style="fixed-case">BPA‐ style="fixed-case">PEG‐ style="fixed-case">LP encapsulating doxorubicin ( style="fixed-case">BPA‐ style="fixed-case">PEG‐ style="fixed-case">LPDOX, 2 mg/kg/day as the style="fixed-case">DOX dosage) or style="fixed-case">PEG‐modified liposomes encapsulating style="fixed-case">DOX ( style="fixed-case">PEG‐ style="fixed-case">LPDOX). As a result, style="fixed-case">BPA‐ style="fixed-case">PEG‐ style="fixed-case">LPDOX significantly suppressed the growth of the style="fixed-case">DU145 cancer cells, whereas style="fixed-case">PEG‐ style="fixed-case">LPDOX at the same dosage as style="fixed-case">DOX showed little anti‐cancer effect. The present study suggested that style="fixed-case">BPA‐ style="fixed-case">PEG‐ style="fixed-case">LP could be a useful drug carrier for the treatment of human prostate cancers.