体内连续筛选法建立可视化乳腺癌肝转移裸鼠模型

目的 建立整体可视化原位乳腺癌肝转移模型,实时观察乳腺癌发展、转移的规律,为研究乳腺癌肝转移的机制以及治疗提供一种更好的动物模型.方法 利用pEGFP-N1表达质粒转染乳腺癌高转移亚系MDA-MB-231细胞,经稳定筛选后建立稳定表达绿色荧光蛋白(EGFP)的乳腺癌细胞株pEGFP-MDA-MB-231细胞.利用pEGFP-MDA-MB-231癌细胞株通过体内连续传代,建立乳腺癌高肝转移模型,并借助整体荧光成像系统采集、分析乳腺癌细胞发出的荧光信号,实时观察乳腺癌细胞在裸鼠原位生长及肝转移情况.结果 乳腺癌细胞pEGFP-MDA-MB-231稳定、高效表达EGFP,通过体内连续筛选法建立乳腺癌原位接种模型后,第1代、第2代、第3代原位接种模型的肝转移率分别为20%、80%、100%.并通过常规病理学方法验证了可视化模型的可靠性.结论 利用稳定转染的乳腺癌pEGFP-MDA-MB-231细胞通过裸鼠体内连续筛选可以建立高效、相对特异性的整体可视化原位乳腺癌肝转移模型,为研究乳腺癌肝转移的机制及治疗提供一种更可靠有效的实验模型.

Establishment of a whole-body visualization model of breast cancer with high hepatic metastatic potential in nude mice through serial passage in vivo

OBJECTIVE: To establish a whole-body visualization model of breast cancer with high hepatic metastatic potential in nude mice and observe the development and metastasis of breast cancer by real-time imaging. METHODS: pEGFP-N1 plasmid was transfected into human breast cancer cell line MDA-MB-231 to obtain pEGFP-MDA-MB-231 cells that emitted fluorescence. pEGFP-MDA-MB-231 cells were inoculated orthotopically in BALB/C nude mice and cultured in vivo through serial passage, thereby establishing the mouse model bearing tumors with high hepatic metastasis potential. The fluorescence emitted from the tumors was quantitatively detected and imaged with a fluorescence stereo microscope for real-time visualization of the tumor growth and metastasis. RESULTS: The transfected breast cancer cells stably and efficiently expressed EGFP. After inoculation of the transfected cells in nude mice, 20% of the first-generation cells showed hepatic metastasis, and the rate increased to 80% among the second-generation and up to 100% among the third-generation cells. The reliability of this visualization model was validated with conventional pathological methods. CONCLUSION: The whole-body visualization model bearing breast cancer with high hepatic metastasis potential provides a reliable means for studying the mechanisms of hepatic tumor metastasis, and can be instrumental in the exploration of novel means for breast cancer treatment.