Development of a novel orthotopic transplantation model of human small cell lung cancer metastasis.

由于小细胞肺癌（SCLC）是一种具有高度转移活性的侵袭性癌症，揭示SCLC转移的分子基础对于改善SCLC治疗具有重要意义。在本研究中，我们建立了一种新的SCLC原位转移的体内模型，并利用该模型研究了转移的分子机制。我们发现在我们的模型中使用的细胞同时表达HGF及其受体c-MET，并且条件培养基增强了细胞的运动性。这些数据表明，在我们的模型中存在HGF/MET自分泌环，就像在SCLC患者中一样。此外，我们通过体内选择周期建立了具有更高转移活性的细胞的新亚克隆，并成功地利用该亚克隆改进了我们的模型。

Because small cell lung cancer (SCLC) is an aggressive cancer with highly metastatic activity, it is important to reveal the molecular basis of the SCLC metastasis for improvement of SCLC therapeutics. In this study, we developed a new in vivo orthotopic model for SCLC metastasis and investigated the molecular mechanism of metastasis using the model. We found that cells used in our model expressed both HGF and its receptor c-MET, and that condition medium of the cells enhanced motility of them. These data suggest the existence of an HGF/MET autocrine loop in our model as in SCLC patients.Moreover, we established a new subclone of the cells with higher metastatitic activity through in vivo selection cycles, and successfully improved our model using this subclone.