Stem Cells in Normal Mammary Development and Cancer

描述（由申请人提供）：本研究的长期目标是阐明干细胞在正常乳腺发育和肿瘤发生中的作用。乳腺干细胞是一群自我更新的多能祖细胞，可产生乳腺特异性肺泡细胞、肌上皮细胞和管腔细胞。乳腺干细胞类似于癌细胞，具有自我更新的潜力。干细胞的长期自我更新潜力使这些细胞更容易积累突变，最终导致肿瘤。这项研究的假设是，正常乳腺干细胞的自我更新机制与癌细胞的自我更新机制相似。该提案的具体目标是找到用于识别和定位正常乳腺和乳腺肿瘤内干细胞的标记物，找到干细胞自我更新所必需的新基因和信号通路，并确定乳腺肿瘤中正常自我更新通路可能被破坏的机制。干细胞抗原-1（Sca-1）、Hoechst染色、罗丹明染色和乳腺癌耐药蛋白-1（BCRP-1）抗体的组合将用于富集自我更新、多能祖细胞群，并将干细胞定位在乳腺和肿瘤内。然后将通过消减杂交、微阵列分析和真实的时间PCR来研究癌症和正常干细胞，以发现额外的新的乳腺特异性干细胞标记物并阐明参与其自我更新的新基因。

DESCRIPTION (provided by applicant): The long-term objective of this research is to elucidate the role of stem cells in normal mammary gland development and tumorigenesis. Mammary stem cells are a population of self-renewing multipotent progenitor cells that can give rise to mammary specific alveolar, myoepithelial, and luminal cells. Mammary stem cells resemble cancer cells in their potential to self-renew for the life of an organism. The long-term self-renewal potential of stem cells makes these cells more susceptible to accumulating mutations that eventually give rise to tumors. The hypothesis of this research is that the mechanisms for self-renewal in normal mammary stem cells are similar to those employed by cancer cells. The specific aims of this proposal are to find markers for the identification and localization of stem cells within normal mammary gland and mammary tumors, to find novel genes and signaling pathways essential for the self-renewal of stem cells, and to determine the mechanism by which normal self-renewal pathways may be disrupted in mammary tumors. A combination of Stem Cell Antigen-1 (Sca-1), Hoechst staining, Rhodamine staining, and Breast Cancer Resistance Protein-1 (BCRP-1) antibody will be utilized to enrich for a population of self renewing, multipotent progenitors and to localize stem cells within the mammary gland and tumors. Cancer and normal stem cells will then be studied by subtractive hybridization, microarray analysis, and real time PCR to find additional novel mammary specific stem cell markers and to elucidate novel genes involved in their self-renewal.