Leslie Dan Faculty of Pharmacy, University of Toronto, 144 College Street, Toronto, Ontario, M5S 3M2, Canada.
Pharm Res. 2009 Oct;26(10):2343-57. doi: 10.1007/s11095-009-9951-x. Epub 2009 Aug 15.
This work focused on the characterization and in vitro/in vivo evaluation of an alginate/chitosan microsphere (ACMS) formulation of glucose oxidase (GOX) for the locoregional delivery of reactive oxygen species for the treatment of solid tumors.
The GOX distribution and ACMS composition were determined by confocal laser scanning microscopy and X-ray photoelectron spectroscopy. The mechanism of GOX loading and GOX-polymer interactions were examined with Fourier transform infrared spectroscopy and differential scanning calorimetry. In vitro cytotoxicity and in vivo efficacy of GOX-encapsulated ACMS (ACMS-GOX) were evaluated in EMT6 breast cancer cells and solid tumors.
GOX was loaded into calcium alginate (CaAlg) gel beads via electrostatic interaction and the CaAlg-GOX-chitosan complexation likely stabilized GOX. Higher concentrations of GOX near the surface of ACMS were detected. GOX retained its integrity upon adsorption to CaAlg gel beads during the coating and after release from ACMS. ACMS-GOX exhibited cytotoxicity to the breast cancer cells in vitro and their efficacy increased with increasing incubation time. Intratumorally delivered ACMS-GOX significantly delayed tumor growth with much lower general toxicity than free GOX.
The results suggest that the ACMS-GOX formulation has the potential for the intratumoral delivery of therapeutic proteins to treat solid tumors.
本研究专注于海藻酸钠/壳聚糖微球（ACMS）载葡萄糖氧化酶（GOX）制剂的特性及其在局部递送活性氧以治疗实体瘤方面的体外/体内评价。
通过共聚焦激光扫描显微镜和 X 射线光电子能谱测定 GOX 的分布和 ACMS 的组成。采用傅里叶变换红外光谱和差示扫描量热法研究了 GOX 的加载机制和 GOX-聚合物相互作用。在 EMT6 乳腺癌细胞和实体瘤中评价了载 GOX 的 ACMS（ACMS-GOX）的体外细胞毒性和体内疗效。
GOX 通过静电相互作用加载到海藻酸钠（CaAlg）凝胶珠中，而 CaAlg-GOX-壳聚糖的复合可能稳定了 GOX。在 ACMS 的表面附近检测到更高浓度的 GOX。GOX 在包衣过程中吸附到 CaAlg 凝胶珠上以及从 ACMS 释放后保持完整。ACMS-GOX 在体外对乳腺癌细胞具有细胞毒性，其疗效随孵育时间的增加而增加。瘤内递送的 ACMS-GOX 显著延缓了肿瘤生长，其全身毒性明显低于游离 GOX。
结果表明，ACMS-GOX 制剂具有将治疗性蛋白递送至实体瘤以治疗实体瘤的潜力。
