MODEL TO SEQUENTIALLY ANALYZE THE METASTATIC CASCADE

人和动物实体瘤的转移性播散需要 成功完成连续的步骤。 除了增长， 在原发性病变中，细胞必须渗透，在运输过程中存活， 可能需要穿过淋巴结，在靶器官中停滞， 如肺或肝，外渗/建立在目标的实质中 器官，并复制以形成临床上显著的转移性结节。 我们建议开发的模型将由小鼠的亚群组成， 具有可选择的耐药标记的乳腺肿瘤， 监测转移性播散的动力学和途径。 的 酶法铺板后集落形成肿瘤细胞的回收 在选择性培养基中分散的组织提供了高度灵敏的方法， 以定量方式检测隐匿性转移。 通过选择一个 进入细胞的视觉标记（大肠杆菌B-半乳糖苷酶基因），休眠 也可以检测非克隆形成细胞。 一组通过不同途径转移的转移性亚群 (i.e.血行和淋巴途径）至不同部位（即肝脏 和/或肺）和非转移性亚群 在转移性序列中，将被导出和表征。 几 已经获得并部分表征了变体， 说明了这种方法的潜力。 这些变体留置权是 易于在细胞培养物中维持，易于从 液氮，是高度致瘤性的，并且相对于 致瘤性、转移性和药物标记物特性。 这个模型最终将允许人们精确地确定特定的 肿瘤进展的特定阶段的宿主免疫机制， 在转移过程中扩散。

Metastatic dissemination of solid tumors in man and animals requires the successful completion of sequential steps. In addition to growth of the primary lesion, cells must intravasate, survive the transport process which may require the transversal of lymph nodes, arrest in a target organ such as the lung or liver, extravasate/establish in the parenchyma of the target organ, and replicate to form clinically significant metastatic nodules. the model we propose to develop will consist of subpopulations of a mouse mammary tumor which have selectable drug resistance markers that allow us to monitor the kinetics and route of metastatic dissemination. The recovery of colony forming tumor cells after plating enzymatically dispersed tissues in selective media provides a highly sensitive method to detect occult metastases in a quantitative manner. By transfecting a visual marker into the cells (E.coli B-galactosidase gene), dormant nonclonogenic cells may also be detected. A panel of metastatic subpopulations which metastasize via different routes (i.e. hematogenous and lymphatic routes) to different sites (i.e. liver and/or lung) and nonmetastatic subpopulations which fail at different steps in the metastatic sequence are to be derived and characterized. Several variants have already been obtained and partially characterized, illustrating the potential of this approach. These variant liens are easily maintained in cell culture, are readily sorted and recovered from liquid nitrogen, are highly tumorigenic, and are stable with respect to tumorigenic, metastatic, and drug marker properties. This model will ultimately allow one to pinpoint the effect of specific host immune mechanisms on specific stages of tumor progression and dissemination during metastasis.