Functional Analysis of the Chromatin Remodeling Factor SRCAP in Prostate Cells

描述(申请人提供)：前列腺癌在美国的发病率相当高，仍然是男性癌症死亡的第二大常见原因。因此，前列腺癌需要新的治疗策略。为了开发新的治疗方法，重要的是破译前列腺癌发生和发展所涉及的特定分子机制。有证据表明染色质重塑复合体蛋白的异常表达与肿瘤的发生发展有关。染色质结构的调节通常调节蛋白质获得DNA的能力，因此，在调节转录、复制和基因组稳定性等关键过程中起着重要作用。染色质重塑酶的突变加速细胞周期进程，在致癌转化中发挥作用，并使生长停滞通路失活。SNF2相关的CBP激活蛋白(SRCAP)是一种ATPase，它是一个大的多蛋白染色质重塑复合体的核心亚单位，并将组蛋白变异体H_2A.Z掺入核小体。组蛋白H_2A.Z对细胞活力至关重要，参与转录调控，并在细胞周期进程中发挥作用。我们的初步研究表明，SRCAP在前列腺癌细胞中具有促增殖作用。通过siRNA实验减少前列腺癌细胞中SRCAP的表达，导致细胞增殖减少。我们还观察到SRCAP调节六个关键的细胞周期控制基因的表达。这项提案中提出的主要假设是SRCAP促进前列腺癌细胞生长。其具体目的是：(1)确定SRCAP介导前列腺癌细胞增殖信号的机制。我们将进行细胞周期分析，并使用芯片序列分析确定前列腺癌细胞中全基因组的SRCAP和H2A.Z结合。(2)探讨SRCAP缺失对前列腺癌移植瘤模型生长的影响。我们提出了新的方向，涉及前列腺癌中SRCAP和H2A.Z之间的相互作用。这项研究有望揭示前列腺癌发生和发展的新机制。这项提案中概述的研究希望对SRCAP在前列腺癌细胞生物学中的功能作用提供洞察力。从这些研究中获得的信息可用于靶向抑制癌细胞增殖的新途径

DESCRIPTION (provided by applicant): The incidence of prostate cancer is quite high in the United States and continues to be the second most common cause of cancer death in men. Therefore, novel therapeutic strategies are needed for prostate cancer. In order to develop new treatment modalities, it is important to decipher the specific molecular mechanisms involved in prostate cancer development and progression. There is evidence implicating aberrant expression of chromatin remodeling complex proteins in cancer development. Regulation of chromatin structure often modulates the ability of proteins to access DNA, and therefore, is important in regulating key processes like transcription, replication and genome stability. Mutations in chromatin remodeling enzymes accelerate cell cycle progression, play a role in oncogenic transformation, and inactivate growth arrest pathways. The SNF2-related CBP activator protein (SRCAP) is an ATPase that is the core subunit of a large multiprotein chromatin remodeling complex and incorporates the histone variant H2A.Z into nucleosomes. Histone H2A.Z is essential for viability, is involved in transcriptional regulation and plays a role in cell cycle progression. Our preliminary studies indicate that SRCAP plays a pro-proliferative role in prostate cancer cells. Reduction of SRCAP expression in prostate carcinoma cells by siRNA experiments results in decreased cellular proliferation. We also observed that SRCAP regulates expression of six key cell cycle control genes. The major hypothesis addressed in this proposal is that SRCAP promotes prostate cancer cell growth. The specific aims are: (1) To determine the mechanisms by which SRCAP mediates proliferative signaling in prostate carcinoma cells. We will perform cell cycle analysis and determine genome-wide SRCAP and H2A.Z binding in prostate cancer cells using ChIP- seq analysis. (2) To assess the effects of SRCAP depletion on tumor growth in a prostate cancer xenograft tumor model. We propose novel directions that involve the interactions between SRCAP and H2A.Z in prostate cancer. This study has the promise of uncovering novel mechanism associated with prostate cancer incidence and progression. The studies outlined in this proposal hope to provide insight into the functional role of SRCAP in the biology of prostate cancer cells. Information obtained from these studies can be used to target novel pathways to inhibit cancer cell proliferation