- 學位論文
利用cRGD與短胜肽修飾之標靶微脂粒藥物對於乳癌之治療與評估
Evaluation of cRGD and peptide-modified targeted liposomal Doxorubicin for breast cancer treatment
摘要
摘要 標靶式微脂粒藥物釋放系統應用在治療癌症上一直是臨床上很有興趣之研究。本研究利用不同之標靶分子於載體表面進行修飾之設計概念，增進癌症化學治療藥物對癌細胞的專一性，提高患部藥物濃度，以降低藥物產生之全身性毒害。修飾使用的胜肽為cRGD 胜肽(arginine-glycine-aspartic acid)可與血管內皮細胞上之整合素做專一性的結合，另一胜肽為對乳癌細胞具專一性辨識之L1胜肽。實驗所使用之抗癌藥物為阿黴素(Doxorubicin)，是臨床上治療癌症常使用之藥物，經由螯合DNA抑制拓樸異構酶與產生自由基來毒殺癌細胞。將標靶分子插入包覆阿黴素之微脂粒表面，再進行體外細胞實驗與體內腫瘤小鼠給藥後觀察其治療效果。由實驗結果顯示，利用流式細胞儀與雷射共軛焦顯微鏡觀察得知，L1修飾之標靶藥物可促進乳癌細胞之胞吞；而cRGD(L2)修飾之標靶藥物因其特殊之結合蛋白專一性辨識也可增加人類內皮細胞之胞吞。利用細胞毒殺實驗觀察結果顯示，利用cRGD(L2)與L1修飾之抗癌藥物其細胞毒殺性在乳癌細胞或內皮細胞上均較未修飾之抗癌藥物高。而在動物實驗方面，於標靶微脂粒的組別中，給藥後在小鼠體重降低幅度較小，且在死亡率部分相對於Lipo-Dox組別較低，顯示標靶微脂粒針對腫瘤部位具有較好的專一性，因此有效地降低毒性，減少對其他組織之副作用。期望此篇研究能增進標靶微脂粒藥物的發展，進而利用於臨床醫學上。
並列摘要
Abstract Tumor targeting drug delivery system combined with liposomes is efficient intracellular delivery system, which may be a useful strategy for anti-tumor clinical therapy. This study aimed to use liposomal Doxorubicin (Lipo-Dox) modified with different ligands binding with the integrin receptors overexpressed on the breast cancer cells or tumor neovasculature endothelial cells. It administered to improve cancer chemotherapy by its specific binding ability decreasing the systemic nature poisoning. The cRGD (cyclic-rginine-glycine-aspartic acid) peptide is specific for tumor neovasculature endothelial cells and the peptide L1 is for breast cancer cells. In vitro experiments, as flow cytometry and confocal microscopy, demonstrated that L1-modified Lipo-Dox can facilitate breast cancer cells uptake; cRGD-modified Lipo-Dox can enhance Human Umbilical Vein Endothelial Cells (HUVEC) uptake via their integrin-mediated endocytosis. In Sulphorhodamine B assay (SRB) experiment revealed that cRGD-L1-modified Lipo-Dox has higher cytotoxicity on breast cancer cells or HUVEC than non-modified Lipo-Dox. In vivo experiments, tumor-bearing mice were prepared by inoculating MDA-MB-231 cells. When tumor volume reached ~100mm3, gave ligand-modified Lipo-Dox via tail vein injection respectively. These results suggest that ligand-modified Lipo-Dox group had effective retardation in the loss of body weight, and decreased mortality. And it also could decreased toxicity efficiently and reduced side effect for its specificity targeting to tumors. The expectation of this research is promoting the progress of tumor targeted drug delivery system, and further improving the clinical therapy.