Role of Cancer Stem Cells in Malignant Progression of Ductal Carcinoma in Situ.

描述（由申请人提供）：我的具体目标是研究癌症干细胞及其微环境在人乳腺癌前病变（导管原位癌（DCIS））亚型恶性进展中的作用。目的是测试癌前细胞系、SUM 225（MCF10ATDCIS.com）和人DCIS亚型是否含有不同的癌症干细胞亚群，其表现出增加的自我更新潜力、静止和致瘤性的独特癌症干细胞特性。我的策略是使用荧光激活细胞分选（FACS）和已知的表面标记物来分离干/祖细胞和分化的亚群，并检查它们的癌症干细胞特性，包括：1）分别通过标准乳腺球测定和在Matrigel中的集落形成的体外自我更新和分化潜力，2）通过使用异种移植到小鼠脂肪垫的人源化基质中的新策略的体内长期和短期自我更新，3）通过生长速率和形成侵入性损伤的潜力的致瘤性，和4）通过长期标记保留研究的静止。此外，内皮细胞在建立癌症干细胞小生境微环境中的作用将通过体外共培养和体内共移植研究来检查。我的基本原理是，癌症干细胞和正常组织干细胞表达相似的表面标记，通过这些标记可以识别和表征它们。一旦确定了癌症干细胞，将努力确定其独特的基因谱。这些研究将为发现针对DCIS亚型的风险评估、预防复发和恶性进展的分子靶点提供基础。 我的长期职业目标是领导一个研究小组，专注于在转化研究环境中预防人类乳腺癌恶性进展。在获得博士学位之前，我担任了七年的学术和临床药理学家。以及细胞信号和小鼠乳腺干细胞生物学基础科学的博士后培训。职业发展奖是与贝勒医学院乳腺癌中心合作获得人类乳腺癌研究额外经验的绝佳机会。贝勒医学院拥有卓越的研究中心和设施，并为科学合作和教育提供了充足的机会。 相关性：乳腺癌前病变可能含有罕见的癌症干细胞群。癌症干细胞可能是不同类型的癌前病变所独有的，并且可以解释为什么有些患者会经历复发或发展为侵袭性癌症，而其他患者则不会。我的目标是研究癌症干细胞在癌前病变亚型侵袭性进展中的作用，并制定侵袭性乳腺癌风险评估和预防的个性化策略。

DESCRIPTION (provided by applicant): My specific aims are to examine the role of cancer stem cells and their niche microenvironment in malignant progression of subtypes of human breast premalignancy, ductal carcinoma in situ (DCIS). The objectives are to test whether premalignant cell lines, SUM225, MCF10ATDCIS.com, and subtypes of human DCIS contain distinct cancer stem cell subpopulations which exhibit unique cancer stem cell properties of increased self-renewal potential, quiescence, and tumorigenicity. My strategy is to use fluorescent activated cell sorting (FACS) and known surface markers to isolate stem/progenitor and differentiated subpopulations and to examine their cancer stem cell properties which include, 1) in vitro self-renewal and differentiation potential by standard mammosphere assay and colony formation in Matrigel, respectively, 2) in vivo long term and short term self-renewal by using a novel strategy of xenotransplantation into humanized stroma of mice fat pads, 3) tumorigenicity by growth rate and potential to form invasive lesions, and 4) quiescence by long term label retaining studies. Furthermore, the role of endothelial cells in establishing a cancer stem cell niche microenvironment will be examined by in vitro co-culture and in vivo co-transplantation studies. My rationale is that cancer stem cells and normal tissue stem cells express similar surface markers by which they may be identified and characterized. Once cancer stem cells are identified, efforts will be aimed at defining their unique gene profiles. These studies will provide a basis for discovery of molecular targets for risk assessment, prevention of recurrence, and malignant progression tailored to subtypes of DCIS. My long term career goal is to lead a research group focused towards prevention of human breast cancer malignant progression in a translational research environment. I served as an academic and clinical pharmacologist for seven years before obtaining a Ph.D. and post-doctoral training in basic sciences in cellular signaling and mouse mammary gland stem cell biology. The Career Development Award is an excellent opportunity to gain additional experience in research in human breast cancer in collaboration with the Breast Cancer Center at Baylor College of Medicine. Baylor College of Medicine houses exceptional research centers and facilities and provides an ample opportunity for scientific collaboration, and education. Relevance: Breast pre-cancer lesions may contain a rare population of cancer stem cells. Cancer stem cells may be unique to different types of pre-cancer lesions and may explain why some patients will experience recurrences or develop invasive cancers while others do not. My goal is to examine the role of cancer stem cells in invasive progression of subtypes of pre-cancer lesions and to develop individualized strategies for risk assessment and prevention of invasive breast cancer.