水溶性紫杉醇前药的制备及抗肿瘤活性的研究

Preparation of anti-cancer water-soluble paclitaxel prodrug and its anti-cancer effect

目的紫杉醇是具有良好抗肿瘤疗效的化学药物,由于紫杉醇本身化学结构复杂,难溶于水,在一定程度上限制了紫杉醇药物在临床上的广泛应用,因此改善紫杉醇水溶性是解决紫杉醇药物不足的关键问题。方法本实验选用水溶性叶酸配体作为"导向基团",谷氨酸为连接叶酸和紫杉醇的Linker,氨基PEG(MW:350)为药物增溶剂和稳定剂,制备水溶性叶酸-PEG-谷氨酸-紫杉醇前药。用LC-MS鉴定前药的化学结构,通过对前药溶解性及释药动力学曲线的测定,确定前药的理化性质。用MTT实验分析并对比紫杉醇原药与前药在不同肿瘤细胞(MCF-7、MDA-MB-231、A549)和正常细胞HELF(人胚肺成纤维细胞)中的毒性和药效作用。用荧光标记法直观观察紫杉醇前药在肿瘤细胞和组织中的靶向性。结果实验结果证明已成功合成叶酸-PEG-谷氨酸-紫杉醇前药,并具有较好的溶解性和原药释放动力学曲线,细胞实验表明在叶酸受体-配体作用的介导下,叶酸-PEG-谷氨酸-紫杉醇前药靶向叶酸受体高表达的肿瘤细胞,减少对叶酸受体低表达正常细胞的毒副作用。结论叶酸-PEG-谷氨酸-紫杉醇前药具有良好的抗肿瘤活性。

Aim Paclitaxel（ PTX） has shown an effect against human cancer. However, serious drawbacks hamper PTX clinical use. Overcoming paclitaxel limitations is one of the best approaches to enhance water solubility. Methods In this study,water-soluble paclitaxel prodrug was prepared,folic acid-polyethylene glycol-glutamic-paclitaxel（ FA-PEG-Glu-PTX） composed of folic acid（ FA,target）,amino acids（ Glu,linker）,and polyethylene glycol（ PEG） in order to improve the solubilization and stability. The chemical structure and physicochemical property of prodrug were measured by LC-MS,solubility,drug release rate to evaluate the antitumor activity and cytotoxicity of FAPEG-Glu-PTX. MTT assays were conducted on MDAMB-231,MCF-7,A549 and HELF cell lines. FAPEG-Glu-PTX prodrugs were labeled with 5 amino fluorescence visible fluorescent dye（ 5AF） for fluorescence microscopy. Results The successful conjugation of FA-PEG-Glu-PTX was confirmed by LC-MS,and had better water solubility,release rate curve. In vitro studies indicated that foliate receptor（ FR-α） mediated uptake of PTX-conjugated multi-small molecules carriers induced highly targeting ability,and antitumor activity,as well as reduced side toxicity effects of PTX.Conclusion FA-PEG-Glu-PTX has a good antitumor activity.