CD44 & Stem Cell Marker (Nanog) in Head and Neck Cancer

描述（由申请人提供）： 摘要头颈部鳞状细胞癌（HNSCC）患者的生存率<50%，其中约90%的癌症非常具有侵袭性并迅速侵入周围组织。晚期HNSCC的晚期检测和治疗选择不足都导致这种致命疾病的预后不良。因此，非常需要鉴定调节HNSCC发展、肿瘤进展和对化学治疗的反应的细胞和分子信号传导组分。越来越多的证据表明，HNSCC细胞过表达某种CD 44亚型[CD 44 v3-透明质酸（HA）受体]，HA-CD 44 v3相互作用促进肿瘤细胞迁移和侵袭所需的肌动蛋白激活剂（N-WASP）介导的细胞骨架功能。干细胞标志物Nanog最初被描述为参与Stat-3信号传导和胚胎干细胞（ES）功能的重要转录因子。我们目前的结果表明，CD 44 v3，Nanog和Stat-3一起似乎赋予HNSCC细胞的恶性特性。最近，microRNA-21（miR-21）也被证明与HNSCC进展的发病机制密切相关。因此，本提案的主要目标是研究由HA/CD 44 v3介导的N-WASP激活的Nanog是否在调节HNSCC进展所需的Stat-3特异性转录活性和致癌miR-21表达/功能中发挥作用。 具体来说，我们假设HA介导的CD 44 v3与N-WASP的相互作用促进细胞骨架活化和Nanog-Stat-3信号传导，导致miR-21产生。这些信号相互作用一起导致肿瘤细胞特异性行为（例如，肿瘤细胞生长、迁移/侵袭、存活和化学抗性）和HNSCC进展。为了解决这一假设，我们计划追求以下三个具体目标：目标1：使用HNSCC细胞培养物阐明新鉴定的HA介导的CD 44 v3与细胞骨架激活剂N-WASP的相互作用及其在调节Nanog-Stat-3信号传导、miR-21产生和由此产生的下游致癌事件中的作用;目标2：使用含有人HNSCC细胞异种移植物的体内小鼠模型研究HA/CD 44 v3与Nanog/Stat-3信号传导和miR-21产生/功能的相互作用对HNSCC进展的影响;以及目的3：分析人类患者HNSCC组织（原发性肿瘤和淋巴结转移瘤）中CD 44 v3、Nanog和关键致癌信号分子沿着miR-21的共表达。将采用各种互补技术来研究HA/CD 44 v3介导的N-WASP与Nanog-Stat-3通路和miR-21表达/功能的相互作用。特别是，该提案中描述的新的信号干扰策略（使用CD 44/Nanog/Stat-3 RNAi和特异性抗miR-21抑制剂）应该揭示，化疗结合抑制CD 44，Nanog，Stat-3和miR-21可以显着提高当前药物治疗的疗效。此外，这些拟议的研究将允许评估共表达的CD 44 v3、Nanog和各种信号传导分子与miR-21（在HNSCC患者样本中）结合作为人HNSCC进展的肿瘤标志物，以及作为潜在的诊断和预后辅助手段。显然，这个拟议的项目具有重要的临床潜力，为退伍军人HNSCC患者开发重要的新治疗方法，使这项工作与VA患者护理使命高度相关。 公共卫生相关性： 近年来，HNSCC被认为是退伍军人人群中非常常见的恶性肿瘤，其危险因素包括吸烟和饮酒。我们提出的项目解决了HA/CD 44 v3亚型-Nanog相互作用和miR-21产生/功能在调节HNSCC行为中的潜在作用（例如，肿瘤细胞迁移、生长、存活和多药耐药性）应该对这种知之甚少的疾病产生有价值的见解。因此，该拟定项目对于HNSCC退伍军人患者的治疗具有潜在的重要临床实用性;因此，它与VA患者护理使命高度相关。

DESCRIPTION (provided by applicant): ABSTRACT Patients with head and neck squamous cell carcinoma (HNSCC) have a survival rate of <50% with approximately 90% of these cancers being very aggressive and rapidly invading the surrounding tissues. Both late detection and inadequate treatment options for advanced HNSCC contribute to the poor prognosis of this deadly disease. Therefore, there is a great need to identify the cellular and molecular signaling components that regulate HNSCC development, tumor progression, and the response to chemotherapeutic treatment. Accumulating evidence indicates that HNSCC cells overexpress a certain CD44 isoform [CD44v3-a hyaluronan (HA) receptor] and that HA-CD44v3 interaction promotes actin activator (N-WASP)-mediated cytoskeleton functions required for tumor cell migration and invasion. The stem cell marker, Nanog, was initially described as an important transcription factor involved in Stat-3 signaling and embryonic stem (ES) cell functions. Our current results indicate that CD44v3, Nanog and Stat-3 together appear to confer the malignant properties of HNSCC cells. Recently, microRNA-21 (miR-21) is also shown to be closely associated with the pathogenesis of HNSCC progression. Therefore, the main goal of this proposal is to investigate whether Nanog, activated by HA/CD44v3-mediated N-WASP, plays a role in regulating Stat-3-specific transcriptional activities and oncogenic miR-21 expression/function required for HNSCC progression. Specifically, we hypothesize that the HA-mediated CD44v3 interaction with N-WASP promotes cytoskeleton activation and Nanog-Stat-3 signaling leading to miR-21 production. Together these signaling interactions result in tumor cell-specific behaviors (e.g., tumor cell growth, migration/invasion, survival and chemoresistance) and HNSCC progression. To address this hypothesis, we plan to pursue the following three specific aims: Aim 1: To elucidate the newly identified HA-mediated CD44v3 interaction with the cytoskeleton activator, N-WASP and its role in regulating Nanog-Stat-3 signaling, miR-21 production, and the resulting downstream oncogenic events using HNSCC cell cultures; Aim 2: To investigate HA/CD44v3 interaction with Nanog/Stat-3 signaling and miR-21 production/function on HNSCC progression using an in vivo mouse model containing xenografts of human HNSCC cells; and Aim 3: To analyze the co-expression of CD44v3, Nanog and key oncogenic signaling molecules along with miR-21 production in human patient HNSCC tissues (primary tumors and lymph node metastases). A variety of complementary techniques will be employed to investigate HA/CD44v3-mediated N-WASP interaction with the Nanog-Stat-3 pathway and miR-21 expression/functions. In particular, the new signaling perturbation strategies (using CD44/Nanog/Stat-3 RNAi, and a specific anti-miR-21 inhibitor) described in this proposal should reveal that chemotherapy combined with the suppression of CD44, Nanog, Stat-3 and miR-21 can significantly improve the efficacy of current drug treatments. Moreover, these proposed studies will allow the evaluation of co-expressed CD44v3, Nanog and various signaling molecules in conjunction with miR-21 (in HNSCC patient samples) as tumor markers for human HNSCC progression, and as potential diagnostic and prognostic aids. Clearly, this proposed project has important clinical potential for the development of important new treatment approaches for Veteran patients with HNSCC, making this work highly relevant to the VA patient care mission. PUBLIC HEALTH RELEVANCE: PROJECT NARRATIVE In recent years, HNSCC has been recognized as a very common malignancy in the Veteran population, with risk factors including tobacco and alcohol usage. Our proposed project addressing the potential role for HA/CD44v3 isoform-Nanog interactions and miR-21 production/function in regulating HNSCC behaviors (e.g., tumor cell migration, growth, survival and multidrug resistance) should yield valuable insights into this poorly understood disease. Thus, this proposed project has potentially important clinical utility for the treatment of Veteran patients with HNSCC; and therefore, it is highly relevant to the VA patient care mission.