Calmodulin Regulates Fas-Mediated Apoptosis: A Target for Cancer Therapy

钙调蛋白调节 Fas 介导的细胞凋亡：癌症治疗的目标

• 批准号: 8195547
• 负责人: Jay M. McDonald
• 金额: --
• 依托单位: BIRMINGHAM VA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-10-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8195547
• 关键词: Alzheimer' s Disease; Animal Model; Apoptosis; Apoptotic; Binding; Biochemical; CASP8 gene; CD95 Antigens; Calcium; Calmodulin; Cancer Diagnostics; Cell Death; Cells; Cessation of life; Characteristics; Chelating Agents; Cholangiocarcinoma; Complex; Cultured Cells; Defect; Development; Diabetes Mellitus; Diagnosis; Diagnostic tests; Disease; Early Diagnosis; Egtazic Acid; Extrahepatic Bile Ducts; Fas Signaling Pathway; Goals; Health; Hepatic; Hepatobiliary; Human; In Vitro; Lead; Malignant Neoplasms; Mediating; Mediator of activation protein; Mus; Nude Mice; Operative Surgical Procedures; Osteoporosis; Pathogenesis; Pathway interactions; Patient Care; Patients; Play; Population; Prevention therapy; Protein Binding; Proteins; Proto-Oncogene Proteins c-akt; Receptor Signaling; Recruitment Activity; Regulation; Resistance; Role; Sampling; Signal Pathway; Signal Transduction; Testing; Therapeutic Agents; Time; Tissue Sample; Translating; Tumor Necrosis Factor Ligand Superfamily Member 6; United States; Veterans; Xenograft Model; Xenograft procedure; advanced disease; biliary tract; cancer cell; cancer therapy; chemotherapeutic agent; cholangiocyte; intrahepatic; novel; novel strategies; overexpression; protein complex; receptor; therapeutic target; tumor; tumorigenesis

6. Project Summary/Abstract. Cholangiocarcinoma is a highly malignant tumor that arises from cholangiocytes of the intra- and extra-hepatic biliary system. Studies from our group and others have found that modulating cell death/apoptosis pathways provide potential novel avenues for cholangiocarcinoma therapy. Downregulating the death receptor (Fas) and upregulating Fas Ligand in cholangiocarcinoma cells protect cells from apoptosis and enhance their tumorigenesis in mice. Further, several anti-apoptotic mediators in the Fas signaling pathways, including protein kinase B/AKT and FLICE like Inhibitory Protein (FLIP) are upregulated in cholangiocarcinoma cells, which render the cancer cells more resistant to apoptosis and divert Fas-induced signaling to survival and proliferative pathways. With human cholangiocarcinoma samples we demonstrated that the expression of Fas is associated with tumor differentiation. We have found that antagonists of calmodulin (CaM) induce apoptosis of cholangiocarcinoma cells via a mechanism related to the Fas-mediated apoptosis pathways and inhibit tumorigenesis in mice. Mechanistic studies further identified Ca2+-dependent direct binding between CaM and Fas, which is regulated upon Fas-activation. In addition, CaM is recruited into the Fas-activated death inducing signaling complex (DISC). A CaM antagonist and a calcium chelator inhibit recruitment of CaM into the Fas-induced DISC and block the recruitment of FADD into the DISC, suggesting that CaM/Fas binding contributes to Fas-activated DISC formation. Recently, we found that CaM binds to FLIP, another DISC protein that is elevated in cholangiocarcinoma cells and activates survival signals upon Fas activation. Therefore, we hypothesize that CaM is a critical regulator of the Fas- death receptor signaling pathway and represents a potential therapeutic target for cholangiocarcinoma. In this application, we will continue pursuing our long-term goal of understanding the Fas death receptor signaling pathways in the pathogenesis of cholangiocarcinoma by focusing on determining the role of CaM in regulating the Fas-activated DISC and the function of CaM/Fas and CaM/FLIP binding in regulating proliferation and apoptosis of cholangiocarcinoma in culture and tumorigenesis in animal models. The Specific Aims are: 1) characterize the function of CaM in regulating Fas signaling pathways in cholangiocarcinoma cells; and 2) characterize the role of the CaM/Fas/FLIP interaction in regulating cholangiocarcinoma tumorigenesis in mice. The present studies will define the fundamental mechanisms by which CaM regulates signaling through the Fas pathway, thus facilitating further studies to translate these findings into strategies and therapies for patient care. Considering that cancer is one of the important health problems in the Veteran's population, our studies will lead to improvement of the health of veterans.

6。项目摘要/摘要。胆管癌是一种高度恶性肿瘤，由 内部和肝外胆道系统的胆管细胞。我们小组和其他人的研究发现 调节细胞死亡/凋亡途径为胆管癌提供了潜在的新途径 治疗。下调胆管癌细胞中的死亡受体（FAS）和上调FAS配体 保护细胞免受细胞凋亡的影响，并增强其在小鼠中的肿瘤发生。此外，几种抗凋亡 FAS信号通路中的介质，包括蛋白激酶B/AKT和抗抑制蛋白 （翻转）在胆管癌细胞中上调，这使癌细胞对凋亡具有更耐药性 并将FAS诱导的信号转移为存活和增殖途径。与人胆管癌 样品我们证明了Fas的表达与肿瘤分化有关。我们找到了 钙调蛋白（CAM）的拮抗剂通过与 FAS介导的凋亡途径并抑制小鼠的肿瘤发生。机械研究进一步确定了 Ca2+依赖性直接结合在CAM和FAS之间，在FAS激活时受到调节。此外， CAM被招募到FAS激活的死亡诱导信号传导复合物（DISC）中。凸轮对手和 钙螯合剂抑制CAM募集到FAS诱导的光盘中，并阻止FADD的募集 椎间盘表明CAM/FAS的结合有助于FAS激活的椎间盘形成。最近，我们发现 凸轮与Flip结合，Flip是另一个在胆管癌细胞中升高并激活的椎间盘蛋白 FAS激活后的生存信号。因此，我们假设CAM是FAS-的关键调节剂 死亡受体信号通路，代表了潜在的治疗靶点 胆管癌。在此应用中，我们将继续追求我们理解的长期目标 FAS死亡受体信号通路在胆管癌的发病机理中通过重点确定 CAM在调节FAS激活的椎间盘以及CAM/FAS和CAM/FLIP结合的功能中的作用 调节胆管癌在动物模型中的培养和肿瘤发生中的增殖和凋亡。 具体目的是：1）表征CAM在调节FAS信号通路中的功能 胆管癌细胞； 2）表征CAM/FAS/FLIP相互作用在调节中的作用 小鼠的胆管癌肿瘤发生。本研究将定义基本机制 CAM通过FAS途径调节信号传导，从而促进进一步的研究以翻译这些 发现患者护理的策略和疗法。考虑到癌症是重要的健康之一 退伍军人人口的问题，我们的研究将导致退伍军人健康的改善。