基于双模态光学成像策略建立原位膀胱癌动物模型

Stable, reliable and reproducible orthotopic animal models are critical, as they provide an opportunity for studying the mechanism of pathogenesis, and allow for research and development of novel therapeutic agents. Traditional animal models are yet unsatisfactory for these models lack the ability to intuitively and dynamically observe the growth and metastasis of cancer in vivo. Therefore, new animal models are necessary to facilitate the detection of growth and metastasis of bladder cancer. In the present study, a bimodal imaging strategy will be developed, which is a very important tool to investigate the growth and metastasis of bladder cancer. We will construct the recombinant lentivirus carrying the firefly luciferase gene(Fluc) and red fluorescent gene(RFP) and to transfect the recombinant lentivirus into human bladder cancer KU-7 cell line(KU-7-Fluc-RFP), so as to observe the expression levels of these two genes. we established and observed subcutaneous and orthotopic xenografts in nude mice by in vivo bioluminescence and fluorescence imaging, which was verified by our post-mortem histological analysis. We propose a model that allows the use of image analysis software to accurately measure the growth and response of orthotopically implanted dual-labeled human bladder cancer cells to intravesical drug treatment. For this purpose, we used doxorubicin (Dox), an anthracycline antibiotic commonly used in maintenance therapy for bladder cancer. This mouse orthotopic bladder model may serves as a powerful and objective tool proving to be more sensitive than histology. Additionally, using this method allows the investigator to conduct more labor-effective and cost-effective experiments with minimal investment which requiring precise objective quantitative analysis of tumor size.

原位膀胱癌动物模型是模拟膀胱癌自然生长状态及进行膀胱腔内灌注治疗研究的必要工具。传统模型由于不能对活体肿瘤的生长过程进行动态描述，因而无法精确评价药物疗效。基于双模态光学成像策略，本研究拟建立一种新的膀胱癌模型系统。构建表达荧光素酶/红色荧光蛋白双报告基因的慢病毒载体，体外转染人膀胱癌KU-7细胞株，建立Fluc/RFP双标的膀胱癌细胞株KU-7-Fluc-RFP。将KU-7-Fluc-RFP细胞种植于裸鼠皮下，评价细胞在体成瘤特性及光学成像灵敏性；将KU-7-Fluc-RFP细胞悬液经膀胱灌注，种植于裸鼠的膀胱腔内，建立原位膀胱癌模型。以Xenogen IVIS200小动物活体成像系统进行生物发光成像与荧光成像，实时观察肿瘤生长及进展。以表阿霉素膀胱灌注治疗，观察在体肿瘤对药物治疗的反应。这一模型系统有望实现生物发光成像与荧光成像的优化组合，可以为新型药物的筛选和鉴定提供可靠的研究平台。

原位膀胱癌动物模型是模拟膀胱癌自然生长状态及进行膀胱腔内灌注治疗研究的必要工具。传统模型由于不能对活体肿瘤的生长过程进行动态描述，因而无法精确评价药物疗效。基于双模态光学成像策略，本研究建立了一种新的膀胱癌模型系统。构建表达绿色荧光蛋白/红色荧光蛋白双报告基因的慢病毒载体，体外转染人膀胱癌T24细胞株，建立GFP/RFP 双标的膀胱癌细胞株(T24 DUAL)。将T24 DUAL细胞种植于裸鼠皮下，评价细胞在体成瘤特性及光学成像灵敏性；将T24 DUAL细胞悬液经膀胱灌注，种植于裸鼠的膀胱腔内，建立原位膀胱癌模型。以Xenogen IVIS200 小动物活体成像系统进行荧光成像，实时观察肿瘤生长及进展。以吉西他滨、表阿霉素膀胱灌注治疗，观察在体肿瘤对药物治疗的反应。这一模型系统实现了双荧光蛋白膀胱癌细胞中的表达，有助于今后研究膀胱肿瘤细胞核-细胞质的动力学相互作用，在亚细胞水平观察肿瘤细胞对药物治疗的反应，可以为新型药物的筛选和鉴定提供可靠的研究平台。