Therapeutic Effects of Paclitaxel-Loaded Hydroxyapatite-Alginate Beads: <i>In Vitro </i> and <i>In Vivo</i> Studies

Abstract

Several drug delivery carriers have reported on local delivery of paclitaxel (PTX), but their effects on intraosseous cancer model are not well known. This study was conducted to clarify the therapeutic effects of our newly developed PTX-loaded HAp-alginate composite beads. Cytotoxic activity was assessed on rat’s mammary adenocarcinoma by cell proliferation assay using WST-1 reagent. Antitumor activity was assessed by 8-week-old rat female Fischer 344 rats of metastatic spine cancer. Twenty-three rats were divided into 3 groups: Group 1 (n = 7) and Group 2 (n = 8) was treated with the PTX-loaded HAp-alginate beads using strontium ions and barium ions, respectively. Group 3 (n = 8) was administered with drug-free HAp-alginate beads. We checked disease-free time and survival time among 3 groups. The HAp-alginate beads containing 2.4wt% of PTX showed significant cytotoxic activity on CRL-1666 cells. The effects were decreased with time during 72 h. The animals treated with 2.4wt% of PTX-loaded HAp-alginate beads showed 40% increase in the disease-free time and 25% increase in survival time. Our studies suggest that newly developed HAp-alginate beads can be a candidate carrier of PTX to bone.