Abstract: Objective To establish bone metastasis mouse models of human lung cancer cells injected into the heart under ultrasound guidance. Methods Under ultrasound guidance, human lung cancer A549 and NCI-H1299 cells were injected into the left ventricle of NOD/SCID and BALB/cnu/ nu mice respectively, and the success rate of animal model and the occurrence of bone metastasis were observed by combining with a variety of animal imaging methods such as in vivo imaging,X-ray and Micro-CT. HE staining was used to examine the tumor tissues and bone tissue damages.Results All the animals survived after lung cancer cells were injected into the heart under ultrasound guidance. In vivo imaging showed that luciferase was expressed in the bones of the central axis and limbs of mice. X-ray and Micro-CT reconstructed the three-dimensional bone of mice. There were obvious defects and destruction of bone and periosteum, and the normal bone morphology disappeared, with osteolytic changes. The imaging findings were consistent with the changes of neoplastic bone destruction. Gross necropsy showed that the axial bone and limb joints of the mice were enclosed by tumor tissues, and there were different degrees of bone metastases. Conclusion Ultrasound-guided intracardial injection of lung cancer cell bone metastasis model can effectively improve the success rate of modeling, more accurately simulate the biological characteristics of bone metastasis in clinical lung cancer patients, and provide tools for the study of lung cancer metastasis mechanism, anti-metastasis treatment, and individualized treatment.

Key words: Human lung cancer, Ultrasound;Intracardiac injection, Bone metastasis, Mouse model