ABSTRACT
@#[摘 要] 目的:评价口服携带HPV16 E7 shRNA和IL-12基因的重组短双歧杆菌在小鼠体内抗宫颈癌移植瘤的效果。方法:将pMG36e-E7 shRNA、pMG36e-mIL-12D质粒分别转化短双歧杆菌,经筛选鉴定并扩增获得携带HPV16 E7 shRNA和IL-12 基因的重组短双歧杆菌。通过小鼠皮下宫颈癌细胞移植建立荷瘤小鼠模型。口服重组短双歧杆菌1、7 d后,检测小鼠主要器官(心、肝、脾、肺、肾)和肿瘤组织匀浆液或血清在PYG培养基中形成的菌落数量,评价短双歧杆菌的肿瘤靶向性,以小鼠体内肿瘤生长曲线评估重组短双歧杆菌的抗肿瘤效果,通过主要器官切片H-E染色和检测荷瘤小鼠血清相关细胞因子水平评价口服重组短双歧杆菌的安全性。结果:成功制备重组短双歧杆菌和宫颈癌TC-1细胞移植瘤小鼠。7 d后,移植瘤组织匀浆液和血清的菌落数量证实短双歧杆菌具有靶向体内瘤组织的定殖能力,口服重组短双歧杆菌明显抑制荷瘤小鼠的肿瘤生长(P<0.05或P<0.01),但联合使用携带HPV16 E7 shRNA和IL-12基因的重组双歧杆菌的肿瘤抑制率与单独使用的并无显著差异,治疗后未见对荷瘤小鼠主要器官的损伤和血清中IL-12及IFN-γ的水平明显变化。结论:短双歧杆菌可用作靶向肿瘤的治疗性基因分子递送载体,其对宫颈癌移植瘤的疗效明显且安全可控。
ABSTRACT
OBJECTIVE To prep are Legumain enzyme and mitochondrial double-stage targeted harmine (HM) liposome (KA@HM-LPS)and preliminary evaluate its pharmaceutical properties ,in vitro antitumor effect and biocompatibility. METHODS Firstly,the preparation and homogenization methods of KA@HM-LPS was screened ,and prepared liposomes were characterized. Secondly,the serum stability ,in vitro release rate ,hemolysis percentage of KA@HM-LPS and cell survival rate under KA@BLPS were determines respectively. Finally ,the cell surivival rate ,mitochondrial targeting and inhibitory effects on cell migration and invasion of KA@HM-LPS were determined. RESULTS KA@HM-LPS was prepared by the thin-film dispersion method ,with encapsulation efficiency of (90.50 ± 0.62)% . The extrusion moulding method was selected as homogenization method of KA@HM-LPS. The particle size ,polydispersity index ,and Zeta potential of KA@HM-LPS were (211.40±11.67)nm,0.316± 0.014 and(-14.20±0.49)mV,respectively. In 37 ℃,10% FBS,the particle size of KA@HM-LPS kept stable after 12 h. In vitro release curve of KA@HM-LPS in 20% plasma conformed to Weibull distribution and had the property of sustained release. When HM concentration was 160 μg/mL,the hemolysis percentage of KA@HM-LPS was (4.23±0.19)%,which was much lower than that of free HM ,with safety. When the mass concentration of KA@BLPS reaches 400 μg/mL,the survival rate of LO 2 cells was (94.40 ± 6.12)% ,and the biocompatibility was good. Cell test results in vitro showed that ,inhibitory effect of KA@HM-LPS on liver cancer cells with overexpression of Legumain enzyme (LGMN -SK-Hep-1) was significantly higher than that of normal liver cancer cells SK-Hep- 1; compared with SK-Hep-1,LGMN +-SK-Hep-1 cells had a higher uptake efficiency of the liposome ;KA@HM-LPS could significantly inhibit the migration and invasion of LGMN +- SK-Hep-1 cells. CONCLUSIONS KA@HM-LPS is prepared successfully ,which can effectively inhibit the migration and invasion of liver cancer cells with Legumain enzyme overexpression ,and improve the blood compatibility of HM.