Objective: To provide a reliable modeling method for studying the mechanism of lung cancer brain metastasis.
Method: 18 BALB/nude mice were randomly divided into two groups, orthotopic transplantation from the thoracic cavity, injection from the left ventricle, and inoculation in the logarithmic growth phase of human lung adenocarcinoma PC-9 cells. Vaccination (1 x 106/0.1 mL) of nude mice, kill any serious cash shortage. Nude mice were dissected, lung, brain, liver and kidney metastases were observed, pathological substances were collected, and HE staining was observed.
Results: Ortho-thoracic transplantation group: After 3 weeks, nude mice Nos. 4, 6, and 9 developed chest wall tumor nodules, which gradually increased, while the weight of nude mice Nos. 4 to 6 lost. Let me do it. . Cachexia gradually develops over the course of several weeks and progresses within 5-7 weeks. After opening the chest, extensive gray-white tumor nodules and mass formation were found in the chest cavity, multiple implants were found in the ribs, pleura and spine on both sides, and the lungs were eroded and compressed, pale and remodeled. HE staining showed that extensively transplanted tumors formed on the surface of the lung, which was clearly different from normal lung tissue. Only the sixth nude mouse had brain metastases. Left ventricular injection group: The nude mice began to lose weight at the 3rd week and gradually developed into cachexia. All the nude mice were sacrificed at the 4th week. After thoracotomy: Except for nude mice No. 11 and No. 18, there are 2-3 scattered tumors (about 1-3 mm in diameter) on the chest wall, and the rest of the thoracic visual field is normal. The lung tissue is transparent and there is no tumor formation. HE staining: There were multiple brain metastases of different sizes in 9 nude mice. In situ thoracic cavity implantation group: the brain metastasis rate was 11.1%, and the left ventricular injection group: the brain metastasis rate was 100%.
Conclusion: The method of establishing a lung cancer brain metastasis animal model by left ventricular injection guarantees a higher brain metastasis rate than the orthotopic chest transplantation method.