Cancer and Cell Lineages From Hair Follicle Stem Cells

描述(申请人提供)：在皮肤的两阶段模型中 致癌，一种致癌物质的单一亚致癌暴露(启动) 和随后的慢性再生性表皮足够的增生 大小(促进)可诱发良性肿瘤和恶性肿瘤。肿瘤 启动被认为是将一些角质形成细胞转化为潜伏的。 肿瘤细胞；促进引起肿瘤改变的表达。这个 潜伏的肿瘤细胞的身份长期以来一直是个谜。引人入胜 有证据表明，滤泡角蛋白15(K15)表达 角质形成细胞是皮肤的多潜能前体细胞，是靶细胞。 细胞在两阶段癌变中的作用。我们的目标是检验这一假设，并 以确定这些细胞是否具有干细胞的其他特征。至 为此，我们开发了两种新颖而令人兴奋的方法。我们的特定 目标如下。1.鉴定、分离、鉴定干细胞 利用K15启动子序列表达K15活细胞的特性 在转基因小鼠中表达绿色荧光蛋白。2.确定是否 表达K15的细胞是皮肤的多潜能祖细胞 通过采用细胞特异的和时间上可诱导的策略 命运映射K15表达细胞，从而使血统分析成为可能 成年转基因小鼠皮肤上皮细胞替代。3. 确定表达K15的细胞是否是肿瘤潜伏细胞 使用特定目标2的命运映射策略来识别致癌物暴露的皮肤 在K15表达细胞中瞬时诱导重组酶 肿瘤的起源，从而跟随肿瘤的发展从假定的 祖先。骨髓干细胞的鉴定和物理分离 毛囊开启健康相关研究之门意义重大 包括：基因治疗，干细胞在毛发生长和伤口中的作用 修复、修复致癌物-DNA加合物、鉴定干细胞 调控基因，以及干细胞自我更新的操作。此外，我们的 可诱导谱系分析的新策略在K15以外的应用 启动子或甚至其他角蛋白启动子。该方法适用于任何 由任何器官系统中的任何祖细胞表达的启动子，从而使 对发育过程中大量血统关系的探索 在生物学和癌症研究方面。

DESCRIPTION (provided by applicant): In the two-stage model of cutaneous carcinogenesis, a single subtumorigenic exposure to a carcinogen (initiation) and subsequent chronic regenerative epidermal hyperplasia of sufficient magnitude (promotion) can induce benign and malignant neoplasms. Tumor initiation is thought to convert some of the keratinocytes into latent neoplastic cells; promotion elicits expression of the neoplastic change. The identity of the latent neoplastic cell has long been a mystery. Compelling evidence has led to the hypothesis that follicular keratin 15 (K 15)-expressing keratinocytes are the cutaneous multipotential progenitors and are the target cells in two-stage carcinogenesis. Our objective is to test this hypothesis and to determine whether these cells have other characteristics of stem cells. To this end, we have developed two novel and exciting approaches. Our specific aims are as follows. 1. Identify isolate, and determine the stem cell properties of live K15-expressing cells by using the K15 promoter sequence to express green fluorescent protein in transgenic mice. 2. Determine whether K15-expressing cells are the multipotential progenitors of the cutaneous epithelium by employing a cell specific and temporally inducible strategy for fate mapping the K15-expressing cells, thereby enabling the lineage analysis of cellular replacement in the cutaneous epithelium of adult transgenic mice. 3. Determine whether the K15-expressing cells are the latent neoplastic cells in carcinogen-exposed skin by using the fate mapping strategy of Specific Aim 2 to induce the recombinase transiently in the K15-expressing cells at the time of tumor initiation, thus following the development of tumors from the presumptive progenitors. Identification and physical isolation of the stem cells in the hair follicles opens the door to health-related research of great significance including: gene therapy, the role of the stem cells in hair growth and wound healing, repair of carcinogen-DNA adducts, identification of stem cell regulatory genes, and manipulation of stem cell self-renewal. Furthermore, our novel strategy for inducible lineage analysis has applications beyond the K15 promoter or even other keratin promoters. The method will work with any promoter expressed by any progenitor cell in any organ system, thus enabling the exploration of a vast number of lineage relationships in developmental biology and in cancer research.