The Role of HEF1 in Ovarian Cancer Development, Progression, and Metastasis

描述（由申请人提供）：HEF1/NEDD9/Cas-L（HEF1）是一种分子支架蛋白，介导来自间期粘着斑和有丝分裂中心体的细胞信号传导。在过去的两年中，HEF1表达的改变已被证明在癌症转移中起重要作用。HEF1的表达增加已被证明可诱导胶质母细胞瘤的侵袭，并促进人类和小鼠中的黑色素瘤和肺癌转移。HEF1表达的扰动也与乳腺癌转移有关。 超过70%的上皮性卵巢癌（EOC）病例在晚期被诊断出来，此时疾病已扩散（转移）到卵巢以外。虽然卵巢癌患者在手术减积和化疗后最初反应良好，但大多数患者会复发并最终死于转移性疾病。最近的研究表明，HEF1通常在晚期浆液性EOC中过表达，浆液性EOC是最常见的EOC类型。重要的是，由HEF1激活的几种致癌蛋白也被证明在EOC中被激活或过表达。其中包括粘着斑激酶（FAK）、Src和信号转导和转录激活因子3（STAT3）。卵巢癌中HEF1过表达与FAK、Src和STAT3激活的相关性尚未确定。 该提案的目标是了解HEF1过表达影响卵巢癌发展、进展和转移的细胞机制，并最终验证HEF1和HEF1激活的信号通路作为卵巢癌患者治疗干预的靶点。 这项建议有三个目的。在目标1中，我们将使用诱导型HEF1/Hef1表达构建体和RNA干扰（RNAi）策略来确定内源性人HEF1或鼠Hef1在人和鼠卵巢癌细胞系中的强制表达或缺失的影响。该目的还将研究HEF1在调节STAT3激活和STAT3介导的迁移和侵袭中的作用。在目标2中，我们将使用体内小鼠模型系统来确定EOC发展、进展和转移中肿瘤细胞和/或肿瘤微环境中Hef1表达的特定要求。在目标3中，我们将全面评估HEF1及其与细胞迁移和侵袭相关的关键结合配偶体（例如，FAK、pFAK、Src、pSrc、STAT3和pSTAT3）。使用人EOC组织微阵列，我们将确定这些蛋白质在正常卵巢以及在每种组织学亚型的边界、早期和晚期肿瘤（例如，浆液性、类浆液性、粘液性和透明细胞癌），并将这些模式与包括病理学、治疗和结果的临床数据相关联。 公共卫生相关性：HEF1蛋白表达的变化与乳腺癌、脑癌、皮肤癌和肺癌的转移有关。HEF1过表达也已在卵巢癌中检测到，卵巢癌是一种高度转移性疾病。这项工作将明确HEF1过表达和致癌信号通路激活在卵巢癌中的作用。这些研究可能揭示了HEF1调控的几个重要分子通路，这些通路可用于卵巢癌患者的靶向治疗。

DESCRIPTION (provided by applicant): HEF1/NEDD9/Cas-L (HEF1) is a molecular scaffolding protein that mediates cellular signaling from focal adhesions during interphase and at centrosomes during mitosis. Over the past two years, alterations in expression of HEF1 have been shown to play a significant role in cancer metastasis. Increased expression of HEF1 has been shown to induce invasion in glioblastoma and promote melanoma and lung carcinoma metastasis in humans and mice. Perturbations of HEF1 expression have also been linked to breast cancer metastasis. More than 70% of cases of epithelial ovarian cancer (EOC) are diagnosed at advanced stage, when disease has spread (metastasized) beyond the ovary. While ovarian cancer patients often initially respond well after surgical debulking and chemotherapy, most suffer disease recurrence and ultimately succumb to metastatic disease. Recent studies have shown that HEF1 is commonly overexpressed in advanced stage serous EOC, the most common type of EOC. Importantly, several oncogenic proteins that are activated by HEF1 have also been shown to be activated or overexpressed in EOC. Among these are focal adhesion kinase (FAK), Src and signal transducer and activator of transcription 3 (STAT3). An association of HEF1 overexpression to activation of FAK, Src and STAT3 in ovarian cancer has not yet been established. The goal of this proposal is to understand the cellular mechanisms by which HEF1 overexpression influences ovarian carcinoma development, progression and metastasis and ultimately to validate HEF1 and the signaling pathways activated by HEF1 as targets for therapeutic intervention in ovarian cancer patients. This proposal has three aims. In Aim 1 we will use inducible HEF1/Hef1 expression constructs and RNA interference (RNAi) strategies to determine the effects of enforced expression or depletion of endogenous human HEF1 or murine Hef1 in human and murine ovarian carcinoma cell lines. This aim will also investigate the role of HEF1 in regulation of STAT3 activation and STAT3-mediated migration and invasion. In Aim 2, we will use in vivo mouse model systems to determine the specific requirement(s) of Hef1 expression in tumor cells and/or the tumor microenvironment in EOC development, progression and metastasis. In Aim 3, we will comprehensively evaluate HEF1 and its critical binding partners relevant to cell migration and invasion (e.g., FAK, pFAK, Src, pSrc, STAT3 and pSTAT3) in primary human ovarian tumors. Using human EOC tissue microarrays, we will determine the patterns and relationship of expression of these proteins in normal ovaries as well as in borderline, early and late stage tumors of each histologic subtype (e.g., serous, endometrioid, mucinous and clear cell cancers) and correlate these patterns with clinical data including pathology, treatment and outcome. PUBLIC HEALTH RELEVANCE: Changes in HEF1 protein expression have been linked to metastasis of breast, brain, skin and lung cancers. HEF1 overexpression has also been detected in ovarian cancer, a highly metastatic disease. The proposed work will define the role of HEF1 overexpression and activation of oncogenic signaling pathways in ovarian cancer. These studies may reveal several important molecular pathways regulated by HEF1 that can be targeted for treatment of ovarian cancer patients.