动物造模 z-bio 2022-05-25 475

　　OBJECTIVE: To dynamically monitor tumor growth in nude mice after orthotopic liver cancer modeling and to compare it with pathology, so as to determine the appropriate period of intervention therapy.

　　Methods: HepG2 cells were injected subcutaneously into nude mice, and after tumor formation, they were cut into 1 mm3 tissue blocks and implanted into the liver of 15 nude mice. Ultrasound and magnetic resonance imaging were performed on 5 nude mice at the 4th, 6th, and 8th weeks after modeling. The tumor length and diameter were measured, nude mice were sacrificed after anesthesia, the liver tumor formation was observed by dissection, the tumor length and diameter were measured, and the specimens were sent to pathology.

　　Results: The tumor formation rate of liver cancer in nude mice was 80%. The tumors were all single with clear boundaries. The detection rate of ultrasound was 75%, and the detection rate of MRI was 100%. The average length of the tumor was 4 mm at 4 weeks, and 7 mm at 6 weeks. The average length diameter at 8 weeks was 11 mm. Wilcoxon rank sum test, ultrasound and anatomy comparison, P=0.0059, MRI and anatomy comparison, P=0.208. Monitoring at 4 and 6 weeks showed that liver cancer was uniformly hypoechoic on ultrasound; T2WI showed clear boundary The pathological manifestations of tumor cells are dense, large nuclei, and obvious atypia. On 8 weeks of monitoring, the ultrasonographic manifestations are inhomogeneous and hypoechoic; T2WI is irregular high signal, with cluttered center and uneven distribution. The pathological manifestations are: Necrosis inside the tumor.

　　Conclusion: The tumor formation rate of in situ liver cancer in nude mice modeled by tissue block is high. Imaging features are related to pathological manifestations. MRI is an effective imaging method to monitor tumor growth throughout the whole process. 1mm3 tumor block inoculated in nude mice liver, 4 to 6 weeks may be optimal time for intervention.