BREAST CANCER MOLECULAR CYTOGENETICS

该项目的目的是表征细胞遗传学的变化， 间期乳腺肿瘤细胞。 细胞遗传学分析得出了更好的 了解肿瘤DNA中的分子缺陷，是一个独立的 肿瘤行为的预后标志物，并将有助于确定染色体 特别感兴趣的区域用于进一步的分子分析。 本实用 通过分析中期染色体的经典细胞遗传学已经被 由于难以制备足够的肿瘤， 来自活检组织的中期细胞。 短期治疗后的肿瘤细胞分析 培养物对能够在细胞中增殖的二倍体细胞是选择性的， 限制培养条件。 现在的技术可用于间期肿瘤的细胞遗传学分析 一个细胞接一个细胞的 染色体拷贝数和主要结构 使用荧光原位杂交检测畸变， 染色体特异性DNA探针。 每个染色体的拷贝数将是 使用染色体特异性的着丝粒周围重复探针检测 1、7、11、133、16和17。 这些染色体是根据 他们可能参与了DNA畸变 特定于以下的探针库 低拷贝数序列排列在整个染色体上， “画”这些染色体，以检测易位或复制 主要的染色体区域。 作为染色体特异性的进一步探针， 我们的合作者开发了感兴趣的子区域，它们将 用于检测较小分子的扩增、缺失和易位 地区 类似的技术将被用来表征在多大程度上 细胞遗传学定义的肿瘤细胞亚群具有增殖性 优于其他亚群。 细胞增殖状态将是 通过溴脱氧尿苷的免疫荧光表征测定 与细胞遗传学表征同时掺入， 荧光原位杂交 双色和三色分析将 允许比较由染色体定义的群体之间的增殖 拷贝数或易位的存在。 肿瘤中染色体异常的异质性程度可以通过 用染色体特异性荧光原位杂交技术 probes. 细胞遗传异质性与遗传不稳定性有关， 从而影响肿瘤的发展和进展。 染色体分布 将使用组织中的原位杂交来确定异常 切片，并将与肿瘤结构和 DNA含量和抗原标记的分布。 在程序中 项目，细胞遗传学信息将与肿瘤病理学相关联， 临床随访和相关分子研究。

The aim of this project is to characterize cytogenetic changes present in interphase breast tumor cells. Cytogenetic analysis leads to a better understanding of molecular defects in tumor DNA, is an independent prognostic marker for tumor behavior, and will help to pinpoint chromosome regions of particular interest for further molecular analysis. The utility of classical cytogenetics by analysis of metaphase chromosomes has been limited in solid tumors due to the difficulty in preparing adequate tumor metaphases from biopsy tissue. Analysis of tumor cells after short term culture is selective for diploid cells capable of proliferating in restricted culture conditions. Techniques are now available for cytogenetic analysis of interphase tumor cells on a cell by cell basis. Chromosome copy number and major structural aberrations will be detected using fluorescence in situ hybridization with chromosome-specific DNA probes. Copy number of each chromosome will be detected using peri-centromeric repetitive probes specific for chromosomes 1, 7, 11, 133, 16, and 17. These chromosomes have been chosen based on their likely involvement in DNA aberrations. Probe libraries specific for low copy number sequences lining the entire chromosome will be used to "paint" these chromosomes in order to detect translocations or duplications of major chromosome regions. As further probes specific for chromosomal subregions of interest are developed by our collaborators, they will be used to detect amplifications, deletions, and translocations of smaller regions. Similar techniques will be used to characterize to what extent cytogenetically defined subpopulations of tumor cells have proliferative advantage over other subpopulations. Cell proliferative status will be determined by immunofluorescent characterization of bromodeoxyuridine incorporation simultaneously with cytogenetic characterization by fluorescence in situ hybridization. Two and three color analysis will allow comparison of proliferation between populations defined by chromosome copy number or the presence of translocations. The degree of heterogeneity of chromosome abnormalities in tumors can be defined using fluorescence in situ hybridization with chromosome specific probes. Cytogenetic heterogeneity is related to genetic instability and thus to tumor development and progression. The distribution of chromosome abnormalities will be determined using in situ hybridization in tissue sections, and will be compared to tumor architecture and to the distribution of DNA content and antigenic markers. Within the Program Project, cytogenetic information will be correlated with tumor pathology, clinical followup, and related molecular studies.