Genome-wide and Specific Gene Expression Study of Osteogenic Cells

骨质疏松症是一个主要的公共健康问题，特别是在女性中。骨质疏松症的主要特点是骨矿含量低。 密度(BMD)。女性的骨密度比男性低得多。一些BMD基因/基因组区域具有性别特异性。 更年期与快速的骨质流失有关。 骨髓间充质干细胞(BMMSCs)和外周血单核细胞(PBM)是 成骨细胞(骨形成细胞)和破骨细胞(骨吸收细胞)。 该项目的目标是确定在骨髓间充质干细胞和 低骨密度与高骨密度的女性和绝经状态改变的女性的PBM。这样的基因预计会是 对女性骨密度变异和女性总体健康具有重要意义。 我们对PBM的初步功能基因组研究表明，HDC和RUNX1(没有被广泛研究的 Runx2)基因在确定人类骨密度方面起着重要作用。 项目2建立在这一激动人心的线索之上，以筛选更大和更强大的骨髓间充质干细胞和 3BMS以确认和扩展我们的初步研究，并全面筛选可能对 骨密度。这个项目有两个内在相关的方面或阶段；阶段2中的研究是为了举例说明功能 在完成第一阶段和项目1和3的研究之后进行的研究。 阶段1(初级)：全基因组基因差异表达(WGGDE)研究。 假说：女性BMMSCs和PBM中mRNA表达谱的变化是其发病机制的基础 女性BMD变异，与更年期有关。 具体目标：确定在女性BMMSCs和PBM中差异表达的基因：1)高表达与低表达 BMD；2)绝经前后，从而识别与女性BMD和绝经相关的基因。 我们将招募80名其他方面健康的女性和80名年龄匹配的其他方面健康的男性，年龄在50-55岁之间，分层 不协调的骨密度值和绝经状态(女性)。我们将进行骨髓抽吸，并获得 外周血样。分离骨髓间充质干细胞和外周血干细胞，提取总RNA。微阵列图谱分析 实验和分析将在女性身上进行，以寻找40,000个已知的人类基因和EST。差异化的 表达的基因将通过实时RT-PCR对女性样本进行验证。这些在女性身上被证实的基因将 对男性样本进行实时RT-PCR检测，以检测其性别特异性。 STAGE2(次级)：候选基因分子机制的功能研究。作为一个探索者 例如，我们将介绍并进行深入的功能研究，以剖析HDC和HDC RUNX1基因调控骨密度。我们推测HDC和RUNX1基因对破骨细胞很重要 分化和/或骨吸收和HDC是RLJNX1基因调节BMD的介质。 结果，与项目1和项目3的结果一起，将有力而有效地识别基因和 它们对女性骨质疏松症有一些作用。 确定人类BMD变异的基因，特别是对女性来说，对于深入了解 骨质疏松风险的基本分子机制，2)发现新的治疗途径和靶点 治疗；3)识别遗传易感个体(通过设计诊断DMA芯片)，以便未来的预防措施 干预措施可以针对并基于个人的特定基因类型。

Osteoporosis is a major public health problem, especially in women. It is mainly characterized by low bone mineral density (BMD). Women have much lower BMD than men. Some BMD genes/genomic regions are sex-specific. Menopause is associated with rapid bone loss. Bone marrow mesenchymal stem cells (BMMSCs) and peripheral blood monocytes (PBMs), are precursors for osteoblasts (bone formation cells) and osteoclasts (bone resorption cells), respectively. The GOAL of this project is to identify genes that are differentially expressed (at mRNA levels) in BMMSCs and PBMs in females with low vs. high BMD and with menopausal status changes. Such genes are expected to be important for variation of female BMD and women health in general. Our preliminary functional genomic studies of PBMs suggested HDC and RUNX1 (NOT the extensively studied RUNX2) genes to be important in determining BMD in humans. Project 2 is built upon this stimulating lead to screen much larger and more powerful samples of both BMMSCs and 3BMs to confirm and extend our preliminary studies and to comprehensively screen genes potentially important for BMD. This project has two inherently related aspects or stages; research in Stage 2 is for exemplifying functional studies to follow the completion of research in Stage 1 and in Projects 1 and 3. STAGE1 (Primary): Whole genome gene differential expression (WGGDE) study. Hypothesis: Changes in the mRNA expression profiles in female BMMSCs and PBMs underlie mechanisms of female BMD variation and are associated with menopause. Specific Goals: To identify genes differentially expressed in BMMSCs and PBMs in women: 1) with high vs. low BMD; 2) before and after menopause, and thus identify genes associated with female BMD and menopause. We will recruit 80 otherwise healthy females and 80 age-matched otherwise healthy males aged 50-55, stratified by discordant BMD values and menopausal status (for females). We will perform bone marrow aspiration and obtain peripheral blood samples. BMMSCs and PBMs will be isolated and total RNA extracted. Microarray profiling experiments and analyses will be performed on females for >40,000 known human genes and ESTs. Differentially expressed genes will be verified by real-time RT-PCR with female samples. These verified genes in females will be examined by real-time RT-PCR with male samples to examine their sex-specificity. STAGE2 (Secondary): Functional studies of molecular mechanisms of candidate genes. As an exploratory example, we will present and perform in-depth functional studies to dissect the mechanisms through which HDC and RUNX1 genes regulate BMD. We hypothesize that HDC and RUNX1 genes are important for osteoclast differentiation and/or bone resorption and HDC is a mediator for RLJNX1 gene in regulating BMD. The results, together with those from Projects 1 and Project 3, will powerfully and efficiently identify genes and some of their functions for female osteoporosis. Identifying genes for human BMD variation, especially for women, is important for 1) gaining insights into the fundamental molecular mechanisms of risk to osteoporosis, 2) discovering new pathways and targets for therapeutic cures; 3) identifying genetically susceptible individuals (by designing diagnostic DMA chip), so that future preventions and interventions can be targeted to and based on individuals' specific genotypes.