GENOMIC INSTABILITY & CLONALITY IN TUMOR PROGRESSION

本建议可分为三个部分。 第一个， 直接延伸我们以前的工作基因组不稳定性， 肿瘤进展。 我们测量了自发性的 突变和转移性癌细胞核型变化的产生 和非转移性细胞，但不能证明在 单元格类型之间的任一参数。 但由于 我们选择的参数可能是有限的（点突变）或 从广义（细胞遗传学变化）来看，我们选择了 同源重排（HR）作为确定是否 转移性和非转移性的HR存在显著差异 细胞可以被检测到。 本提案的第二部分将我们的兴趣扩展到 发展到克隆优势的问题， 进展的，即转移性细胞的发展。 最近的报告 已经表明（在小鼠模型中）， 单个克隆不仅支配原发性肿瘤，而且支配 转移 我们将使用分子技术来解决这个问题 并确定克隆优势是否是一个特征 人类肿瘤 因为我们相信克隆的机制 显性的发生与基因组的不稳定性有关（请参见正文）， 这些分析建立了基因组之间的合理联系， 不稳定和进步。 这个问题也将在 在乳头状瘤转化为 癌 本建议的第三部分涉及我们的假设， 肿瘤进展有两种类型，即所见的经典型 在结肠癌（1型）和加速型（2型）中， 这在大多数其他肿瘤中也会发生。 我们选择了未知的主要 作为典型的2型肿瘤 进步者 这些研究旨在定义2型肿瘤 使用核型分析来确定独特的染色体 这些肿瘤的变化。 我们还计划使用 包含在前两个部分，以研究 1型和2型进展者之间的差异。 因此，我们建议继续我们先前的工作 及其利用分子遗传技术扩展到新领域 评估基因组不稳定性和肿瘤进展。

This proposal can be divided into three sections. The first, is direct extension of our previous work on genomic instability in tumor progression. We had measured the rate of spontaneous mutation and of the generation of karyotypic changes in metastatic and non-metastatic cells but could not demonstrate a difference in either parameter between the cell types. However, because the parameters we chose may have been to finite (point mutations) or to broad (cytogenetic changes), we have chosen to look at homologous rearrangements (HR) as a means of determining if significant differences in HR for metastatic and non-metastatic cells can be detected. The second section of this proposal extends our interest in progression to the issue of clonal dominance in relationship to the development of progressed, i.e. metastatic cells. Recent reports have indicated (in a murine model) that as tumors become metastatic a single clone dominates not only the primary tumor, but also the metastases. We will use molecular techniques to address this issue in human tumors and determine whether clonal dominance is a feature of human neoplasia. Since we believe the mechanism by which clonal dominance occurs relates to genomic instability (please see text), these analyses establish a reasonable link between genomic instability and progression. This issue will also be analyzed in a carcinogenesis model during the conversion of papillomas to carcinomas. The third section of this proposal deals with our hypothesis that tumor progression is of two types, namely the classic form as seen in colon carcinoma (Type 1) and the accelerated form, (Type 2), which occurs in most other tumors. We have chosen unknown primary tumors as being the quintessential example of a Type 2 tumor progressor. These studies are aimed at defining Type 2 tumors using karyotypic analyses in an effort to define unique chromosomal changes in these tumors. We also plan to use the approaches contained in the first two sections to study the relationship between Type 1 and Type 2 progressors. We are, therefore, proposing a continuation of our earlier work and Its extension to newer areas using molecular genetic techniques to assess genomic instability and tumor progression.