双功能RGD-R8修饰阿霉素脂质体的制备及其体外评价

Preparation of bifunctional RGD-R8 peptide modified doxorubicin liposome and in vitro evaluation

目的制备串联的RGD-R8肽修饰阿霉素(DOX)脂质体(RGD-R8-LP-DOX),对其理化性质进行表征,并研究脂质体与乳腺癌MCF-7细胞的亲和力和增殖抑制作用。方法采用薄膜分散法制备RGD-R8-LP-DOX,研究脂质体的形态、粒径、电位以及包封率;定量细胞摄取实验研究乳腺癌MCF-7细胞对RGD-R8-LP的摄取效率以及对脂质体摄取的影响因素。定性共聚焦实验观察肿瘤细胞对脂质体的摄取。MTT实验研究RGD-R8-LP-DOX对乳腺癌MCF-7细胞的细胞毒性。结果 RGD-R8-LP-DOX的粒径为(115.8±11.5)nm,电位为(23.45±4.68)mV,阿霉素的包封率为95.6%。细胞摄取实验结果显示,RGD-R8-LP在4 h摄取效率是2 h的1.75倍,差异有统计学意义(P<0.05);MCF-7细胞在与脂质体共同孵育4 h后对RGD-R8-LP的摄取效率分别是R8-LP、RGD-LP和LP的2.1倍、2.9倍和3.8倍,差异有统计学意义(P<0.01);RGD-R8-LP-DOX与乳腺癌MCF-7细胞孵育24 h后的存活率是48 h的1.8倍,差异有统计学意义(P<0.05);在给药48 h后,R8-LP-DOX、RGD-LP-DOX和LP-DOX的细胞存活率分别是RGD-R8-LP-DOX组的1.6倍、1.8倍和2.4倍,差异有统计学意义(P<0.01)。结论整合素受体特异性配体RGD和细胞穿膜肽R8串联的RGD-R8肽修饰阿霉素脂质体能够有效穿透肿瘤细胞膜进入肿瘤细胞,是一种潜在高效的乳腺癌给药系统。

Objective To prepare RGD-R8 modified doxorubicin liposome（ RGD-R8-LP-DOX） and to study its activity on breast cancer MCF-7 cells.Methods RGD-R8-LP-DOX was prepared by film-ultrasonic dispersion method.The appearance,particle size,Zeta potential,and entrapment efficiency were evaluated.The cellular uptake of RGD-R8-LP by MCF-7 cells in vitro was used to evaluate the targeting efficiency.The anti-proliferation efficiency of RGD-R8-LP-DOX was evaluated by MTT assay.Results The particle diameter of the liposome was 115.8 ± 11.5 nm with the Zeta potential of 23.45 ± 4.68 mV.The entrapment efficiency of DOX was 95.6%.The RGD-R8-LP uptaking rate by MCF-7 cells at 4 h was 1.75 times higher than that at 2 h（ P〈0.05）.The RGD-R8-LP uptaking rate by MCF-7 cells was 2.1,2.9 and 3.8 times higher than that of R8-LP,RGD-LP and LP,respectively（ P〈0.01）.The cell viability of MCF-7 cells treated by RGD-R8-LPDOX for 24 h was 1.8 times higher than that for 48 h（ P〈0.05）.MTT assay demonstrated that after 48 h treatment,the cell viability of MCF-7 cells treated by R8-LP-DOX,RGD-LP-DOX and LP-DOX were 1.6,1.8and 2.4 times higher than that of RGD-R8-LP-DOX（ P〈0.01）,respectively.Conclusion RGD-R8-LPDOX might serve as a promising breast cancer delivery system of antitumor drugs.