Development of experimental system to analyze the involvement of bone marrow during lung metastasis

骨肉瘤患者的预后取决于肺转移。近年来，骨髓在肿瘤转移发生中的作用逐渐被阐明。在本研究中，我们首次报道了间充质干细胞成骨分化过程中细胞运动和运动方式的变化机制——骨肉瘤的起源。接下来，我们比较了高转移性小鼠骨肉瘤细胞系lm8与亲代Dunn细胞之间的肺转移能力。小鼠骨髓中均未发现LM8和Dunn，但两种细胞系在外渗（侵入肺内皮细胞）这一步骤中存在显著差异。因此，我们报道了小鼠骨肉瘤建立肺转移的侵袭性能力的参与。

Prognosis of patients suffering osteosarcoma depends on lung metastasis. Recently the role of bone marrow in the establishment of metastasis shed lights. In this study, we firstly reported the mechanism of change in the cellular motility and motile mode during the osteoblastic differentiation of mesenchymal stem cells-origin of osteosarcoma. Next, we compared the ability of lung metastasis between highly metastatic mouse osteosarcoma cell line, LM8-establisged in our laboratory, and parental Dunn cells. Neither LM8 nor Dunn found in the mouse bone marrow, while striking difference exist during the step of extravasation (invasion onto the endothelial cells of lung) between two cell lines. We thus reported the involvements of invasive ability to establish lung metastasis in mouse osteosarcoma.