CENTROSOME HYPERTROPHY IN HUMAN BREAST TUMORS

描述：(改编自研究人员的摘要)中心体 在维持细胞极性中的作用，并通过 通过确定细胞周期的数量、极性和组织 间期和有丝分裂的纺锤体微管。中心体缺陷 组织和职能对该组织有深远的影响，包括 细胞极化特征丧失和染色体分离 在许多癌细胞中看到的异常。细胞周期检查点调控 中心体复制被认为是在P53的影响下进行的。 在初步研究中，他们仔细检查了 中心体在人类乳腺肿瘤中确定中心体异常 发生在这些细胞中。初步研究揭示了引人注目的和 乳腺肿瘤几种中心体性质的特征性变化 细胞包括：关键中心体蛋白的过度积累， 额外的中心粒，以及不适当的磷酸化状态 中心体蛋白。此外，他们还开发了一种新型微管 核试验用于评价乳腺肿瘤细胞中心体功能。他们的 初步研究进一步表明，乳腺肿瘤细胞显示 以不适当为特征的特定功能中心体异常 形成大的微管紫锥体的MTOCs的数量。因此，他们 建议：1)确定中心体的细胞周期调控机制 在正常乳腺上皮和乳腺肿瘤来源的细胞系中复制， 2)确定以下变更之间的功能关系 中心体结构与细胞极性的丧失和增加 乳腺癌中的染色体分离异常，以及3)到 系统地、定量地表征分子和结构 人乳腺组织中心体异常的标志物 增殖性和非增殖性纤维囊性疾病、LCIS、DCIS和 浸润性导管和小叶癌。 拟议的研究代表了一种新的方法来理解 细胞极性丧失和倾向增加的机制 在许多癌细胞中看到的染色体分离异常，以及 这些研究可能会为小说的发展提供新的目标 临床干预。

DESCRIPTION: (adapted from the investigator's abstract) The centrosome functions in maintenance of cell polarity and in progression through the cell cycle by determining the number, polarity, and organization of interphase and mitotic spindle microtubules. Defects in centrosome organization and function have profound consequences for the cell, including the characteristic loss of cell polarlity and chromosomal segregation abnormalities seen in many cancer cells. Cell cycle checkpoints regulating centrosome duplication are believed to operate under the influence of p53. In preliminary studies, they have performed a careful examination of centrosomes in human breast tumors to determine if centrosome abnormalities occur in these cells. The preliminary studies have revealed striking and characteristic changes in several centrosome properties in breast tumor cells including: excess accumulation of key centrosomal proteins, supernumerary centrioles, and inappropriate phosphorylation status of centrosome proteins. In addition, they have developed a novel microtubule nucleation assay to assess breast tumor cell centrosome function. Their preliminary studies further demonstrate that breast tumor cells show specific functional centrosome abnormalities characterized by inappropriate numbers of MTOCs that nucleate large microtubule asters. They, therefore, propose to: 1) determine the cell cycle control mechanism for centrosome duplication in normal breast epithelial and breast tumor derived cell lines, 2) to determine the functional relationship between alterations in centrosome structure and the loss of cell polarity and increase in chromosomal segregation abnormalities seen in breast carcinomas, and 3) to systematically and quantitatively characterize molecular and structural markers for centrosome abnormalities in human breast tissues from proliferating and nonproliferating fibrocystic disease, LCIS, DCIS, and invasive ductal and lobular carcinomas. The proposed studies represent a novel approach to understanding the mechanism of loss of both cell polarity and the increased propensity toward chromosomal segregation abnormalities seen in many carcinoma cells, and these studies may provide new targets useful in the development of novel clinical interventions.