可视化人结直肠癌细胞裸鼠直肠原位移植淋巴转移模型的建立

A visualized lymphatic metastasis model of human colorectal cancer cell developed in nude mouse by rectal orthotopic implantation

目的建立可以动态观察直肠癌生长及淋巴转移的原位移植模型,初步探讨活体成像系统观察直肠癌生长和转移的可行性。方法采用裸鼠直肠黏膜下注射红色荧光蛋白标记的人结直肠腺癌细胞HCT 116建立原位移植模型,借助活体成像系统在不同时间点采集荧光信号图像,实时观察癌细胞在裸鼠直肠的生长和转移情况,应用病理学方法对原位移植淋巴转移模型进行验证。结果50只可视化裸鼠直肠原位移植淋巴结转移均成功构建。在原位移植后2~7周,所有裸鼠在活体成像系统中观察到了肿瘤荧光蛋白表达。原位移植后随着时间的延长,移植瘤体积的增大,积分光密度值逐渐增大。裸鼠直肠系膜根部淋巴结转移、主动脉旁淋巴结转移、肝转移和肺转移成时间依赖性增长。组织学检查与依靠淋巴结表达荧光蛋白来判断转移情况的结果一致。结论可视化裸鼠直肠原位移植及淋巴转移模型技术可靠可行。活体成像系统对可视化裸鼠直肠原位移植瘤生长进行实时、无创及动态观测和淋巴转移的观察简便有效。

Objectives To develop an orthotopic xenografts model that can dynamically observe the growth of rectal cancer and lymphatic metastasis,and to preliminarily explore the feasibility of monitoring the growth and metastasis of rectal cancer by in vivo imaging system.Methods An orthotopic xenografts model was developed in nude mouse by rectal submucosal injection of red fluorescent protein-labeled human colorectal adenocarcinoma cell line HCT 116.Then,the fluorescence signal from cancer cells was collected at different time points by means of in vivo imaging system,and the growth and metastasis of cancer cells in the rectum of nude mice was observed in real time.Finally,the model was evaluated by pathology.Results Fifty visualized nude mouse models of orthotopic implantation and lymphatic metastasis were successfully constructed.At 2-7 weeks after implantation,the fluorescent protein of tumor were observed in all nude mouse with in vivo imaging system.After the orthotopic implantation,the volume of the transplanted tumor grew with the extension of time,and the integrated density expanded gradually.The number of caudal mesenteric lymph node metastases,para-aortic lymph node metastases,liver metastases and lung metastases increased timedependent.The results of histological study was consistent with depending on lymph nodes to express fluorescent proteins to determine metastasis.Conclusions It is reliable and feasible to visualize the orthotopic implantation and lymphatic metastasis model of nude mice.The in vivo imaging system is simple and effective for real-time,non-invasive and dynamic observation of the growth of orthotopic xenografts and lymphatic metastasis in nude mice.