BWS AND EMBRYONAL TUMOR SUPPRESSOR GENES ON 11P15

描述：(改编自调查人员的摘要)申请人的 实验室在11p15上发现了几种基因变化 提示该区域在肾母细胞瘤和其他肿瘤中起着关键作用 胚胎性癌症。其中包括11p15的杂合性缺失(LOH)； 11p15与Beckwith-Wiedemann综合征(BWS)的遗传连锁 导致胎儿过度生长和易患多种疾病 胚胎性肿瘤，包括WT和横纹肌肉瘤； 印迹(LOI)，一种新的引起双等位基因改变的基因改变 通常由单个亲本等位基因表达的基因的表达。 为了定位BWS基因，申请人进行了分子克隆 来自BWS的7个生殖系平衡染色体排列断裂点 病人。令人惊讶的是，这些断点发生在两个不同的区域 被4Mb隔开的11p15。申请者还开发了一部小说 用于定位和隔离肿瘤的通用遗传互补策略 抑制基因，使用亚染色体可转移片段(STF) 可以被引入任何哺乳动物细胞。申请人已提出申请 这一策略分离了导致体外生长停滞的区域 横纹肌肉瘤细胞。这个区域与更多的端粒BW重叠 断点群集。这些结果表明，11p15上的多个基因 参与了胚胎肿瘤的发病机制。申请人是 现在正在识别更端粒的BWS断点簇中的基因。 其中之一是p57Kip2，这是一种新近发现的细胞周期蛋白依赖性激酶 第二个是可能与核小体有关的新基因 集合。 申请者将继续分离两个BWS生殖系中的基因 他们克隆的染色体重排断点簇。他 将使用他们的新的STF遗传互补方法来 确定是否存在第二个胚胎肿瘤抑制基因 11p15与更着丝粒的BWS断点群相对应。 酵母人工染色体将直接转移到肿瘤中 细胞，以便进一步界定包含这些基因的区域。 BWS和胚胎肿瘤候选基因的变化也将是 已确认身份。最后，申请人将确定正常的功能 这些基因，包括它们的组织和细胞定位，它们的 基因表达的发育模式及其对基因表达的影响 正常细胞和肿瘤细胞，以及基因改变的后果 体外和体内。这些研究应该会为我们提供新的见解 在单个大的染色体区域中的多个基因改变导致 会发展成胚胎肿瘤。

DESCRIPTION: (adapted from the investigator's abstract) The applicant's laboratory has discovered several genetic alterations on 11p15 that suggest a crucial role for this region in Wilms tumor (WT) and other embryonal cancers. These include loss of heterozygosity (LOH) of 11p15; genetic linkage to 11p15 of Beckwith-Wiedemann syndrome (BWS), which causes fetal overgrowth and predisposition to a wide variety of embryonal tumors, including WT and rhabdomyosarcoma; and loss of imprinting (LOI), a novel class of genetic alteration causing biallelic expression of genes normally expressed from a single parental allele. In order to localize a BWS gene, the applicant has molecularly cloned 7 germline balanced chromosomal arrangement breakpoints from BWS patients. Surprisingly, these breakpoints occur in two separate regions of 11p15 separated by 4 Mb. The applicant has also developed a novel general genetic complementation strategy to localize and isolate tumor suppressor genes, using subchromosomal transferable fragments (STFs) that can be introduced into any mammalian cell. The applicant has applied this strategy to isolate a region that causes in vitro growth arrest of rhabdomyosarcoma cells. This region overlaps the more telomeric BWS breakpoint cluster. These results suggest that multiple genes on 11p15 are involved in the pathogenesis of embryonal tumors. The applicant is now identifying genes within the more telomeric BWS breakpoint cluster. One of these is p57KIP2, a recently identified cyclin-dependent kinase inhibitor, and a second is a novel gene likely involved in nucleosome assembly. The applicant will continue to isolate genes within the two BWS germline chromosomal rearrangement breakpoint clusters that they have cloned. He will use their novel genetic complementation approach of STFs to determine whether there is a second embryonal tumor suppressor gene on 11p15 corresponding to the more centromeric group of BWS breakpoints. Yeast artificial chromosomes will be transferred directly into tumor cells, in order to further delimit the regions harboring these genes. Alterations in candidate genes in BWS and embryonal tumors will be also identified. Finally, the applicant will determine the normal function of these genes, including their tissue and cellular localization, their developmental pattern of expression, the effect of their expression on normal and tumor cells, and the consequences of gene alteration both in vitro and in vivo. These studies should provide novel insights into how multiple genetic alterations in a single large chromosomal domain give rise to embryonal tumors.