人胰腺癌PANC-1细胞裸鼠移植瘤模型建立及其用于观察载siRNA纳米微粒体内效应的研究

 目的：探讨建立人胰腺癌PANC-1裸鼠移植瘤模型的最佳实验方法，并应用该模型进行载基因纳米微粒体内效应的研究。方法：将不同数量PANC-1细胞悬液接种于BALB/c (nu/nu)小鼠右侧背部皮下，当肿瘤体积达100 mm3时尾静脉注射siRNACY5.5纳米复合物进行活体荧光成像。此外，于尾静脉注射负载siRNAKras纳米复合物，蛋白印迹及免疫组织化学染色法观察肿瘤组织Kras蛋白表达水平。结果：1×107 cells/300 μL 接种成瘤率达100%，成瘤时间＜2周。荧光呈像及组织学检查显示载siRNA纳米微粒可靶向聚集在肿瘤组织发挥体内基因沉默效应。结论:本研究报道的人胰腺癌裸鼠移植瘤模型建立方法成瘤率达100%，成瘤时间短，是研究药物示踪和观察疗效的理想模型。

Establishment of human pancreatic tumor xenograft mouse model for evaluating tumor-homing and gene-silencing effects of siRNA-loading nanoparticles

AIM：To establish an effective and rapid method to develop transplanted subcutaneous pancreatic carcinoma by inducing PANC-1 cells into nude mice, and then use this mouse model to evaluate the tumor-homing and gene-silencing effects of siRNA-loading nanoparticles in vivo. METHODS：Different numbers of PANC-1 cells in 100 μL or 300 μL PBS were inoculated subcutaneously into the right flank of BALB/c (nu/nu) mice. When the tumor volume reached 100 mm3, siRNACY5.5 nanoparticles were injected through the mouse tail vein to perform in vivo imaging assay. Besides, the mice were randomly divided into 3 treatment groups treated with PBS, scrambled control RNA nanoparticles and siKras nanoparticles, respectively. The protein expression of Kras was detected by Western blotting and immunohistochemical staining. RESULTS：After inoculated with 1×107 PANC-1 cells in 300 μL PBS, all mice developed tumors within 2 weeks. The in vivo results showed that siRNA-loading nanoparticles accumulated in the tumor tissues and exerted gene silencing effect. CONCLUSION:In the present study, an effective and rapid method was established for PANC-1 cells to induce transplanted subcutaneous pancreatic carcinoma in nude mice within 2 weeks, which is suitable for in vivo imaging and treatment evaluations as a reproducible and reliable way for the further experiments.