Establishment of a nude mouse model of pulmonary adenocarcinoma metastasis / 中国实验动物学报

ABSTRACT

Objective To establish an optimal animal model of pulmonary metastasis of human lung adenocarcino-ma, to serve further investigation of mechanism of lung adenocarcinoma metastasis.Methods Eleven nude mice aged 4-6 weeks were used in this study.Suspension of human lung adnocarcinoma A549 cells (0.1 mL, 107 cells/mL) was injec-ted into the tail vein in nude mice.From four weeks after inoculation, two nude mice were killed each time at 4, 5, 6 weeks after the tumor cell injection at random for examination.The remaining 3 mice were killed at the end of the experi-ment.At autopsy, the lung, brain, liver, kidney and other organs were removed, fixed in neutral buffered formalin and embedded in paraffin.Sections were cut and stained with hematoxylin-eosin, and examined by histopathology.The number of metastatic foci was counted.Results No mouse died after tumor cell inoculation.Serially euthanized mice revealed evi-dence of gradually increasing pulmonary metastases in the miceNo metastasis was found before 4 weeks after tumor cell in-oculation, the first histological metastases appeared at 5 weeks, gross metastatic foci were observed at 6 weeks, widely spread metastatic foci were observed at 7 weeks, and the remain 3 mice developed cachesia at 11, 13, and 14 weeks after tumor cell inoculation.Mediastinal lymph node metastases were found in the nude mice by 11 weeks after tumor cell inocu-lation.Conclusions We have successfully established a nude mouse model of pulmonary metastasis by injecting human lung adenocarcinoma A549 cells into the tail vein.