Regulation of Ovarian Carcinoma Proteinases

描述(申请人提供)：上皮性卵巢癌(EOC)是美国女性癌症死亡的第五大原因，也是妇科恶性肿瘤的主要死亡原因，每年导致15,500人死亡。大多数妇女被诊断为播散性转移性疾病；因此，30年来，卵巢癌的死亡率并没有明显下降。EOC通过剥离原发肿瘤中的单个细胞和多细胞聚集体(MCAS)而转移，这些MCAS在悬液中存活，粘连在腹膜内(IP)，经历局部侵袭到富含胶原的间皮下基质，并增殖以锚定继发性病变。调控EOC转移成功的因素和控制从自由漂浮细胞到威胁生命的腹膜锚定转移灶的转变的因素尚不清楚。上一期的研究强调了1整合素介导的与IP胶原的黏附在膜系胶原酶MT1-MMP4(MMP14)的表达和功能中的作用。这些机制研究产生了关于细胞质尾部磷酸化在调节MT1-MMP膜动力学中的作用的令人兴奋的新数据，发现了MT1-MMP在细胞-细胞贴壁形成MCA中的作用，鉴定了一组参与转移的受整合素信号调节的基因产物，并证明了E-钙粘素动力学和连环蛋白调节的转录是在整合素参与的下游调控的。在目前的提案中，我们将继续解决粘连和蛋白分解之间的功能联系调节卵巢癌转移的假设。Aim 1的研究将使用一组体外和体内分析来评估MT1-MMP细胞质尾巴的翻译后调节如何有助于转移成功，并利用这些分析对EoC IP转移中的关键事件进行机械建模。目标2将评估黏附介导的整合素连接激酶(ILK)激活在EOC转移中的作用。目标3提出的实验将检验整合素对连环蛋白靶基因和上皮/间充质转化的调节作用。EoC IP扩散不同于大多数其他实体肿瘤的血源性转移，因此带来了一系列不同的治疗挑战。在分子水平上了解卵巢癌肿瘤细胞是如何转移的，对于开发抑制IP扩散的新疗法是必要的，从而提高成千上万患有卵巢癌的妇女的存活率。 公共卫生相关性：准确反映上皮性卵巢癌(EOC)转移能力的模型的开发是一个显著的科学挑战，因为EOC的转移机制涉及一种新的多细胞聚集体(MCAS)作为锚定非锚定的、耐化疗的球体脱落到腔(腹膜腔)中。在这个独特的利基环境中，从自由漂浮的大脑中动脉到威胁生命的腹膜锚定转移灶转变过程中发生的分子事件知之甚少。了解这一转变将使针对适当的多细胞群体的腹膜内治疗的新方法成为可能。

DESCRIPTION (provided by applicant): Epithelial ovarian cancer (EOC) is the fifth leading cause of cancer death among US women and the major cause of death from gynecologic malignancy, causing >15,500 mortalities/year. Most women are diagnosed with disseminated metastatic disease; as such the mortality rate from EOC has not been reduced appreciably in 30 years. EOC metastasizes via exfoliation of single cells and multicellular aggregates (MCAs) from the primary tumor that survive in suspension, adhere intra-peritoneally (ip), undergo localized invasion into the interstitial collagen-rich sub-mesothelial matrix and proliferate to anchor secondary lesions. The factors that regulate EOC metastatic success and control the transition from free-floating cells to life-threatening peritoneally anchored metastatic lesion are unknown. Studies in the previous funding period highlighted the role of ¿1 integrin-mediated adhesion to ip collagen in expression and function of the membrane-tethered collagenase MT1-MMP (MMP-14). These mechanistic studies generated exciting new data on the function of cytoplasmic tail phosphorylation in regulation of MT1-MMP membrane dynamics, discovered a role for MT1-MMP in MCA formation from cell-cell adherent sheets, identified a panel of gene products involved in metastasis that are regulated by integrin signaling, and demonstrated that E-cadherin dynamics and ¿-catenin-regulated transcription are modulated downstream of integrin engagement. In the current proposal, we will continue to address the hypothesis that a functional link between adhesion and proteolysis regulates ovarian cancer metastasis. Studies in Aim 1 will evaluate how post-translational regulation of the MT1-MMP cytoplasmic tail contributes to metastatic success using a panel of in vitro and in vivo assays with which to mechanistically model key events in EOC ip metastasis. The role of adhesion-mediated integrin linked kinase (ILK) activation in EOC metastasis will be evaluated in Aim 2. Experiments proposed in Aim 3 will examine integrin regulation of ¿-catenin target genes and epithelial/mesenchymal transition. EOC ip dissemination is distinct from that of most other solid tumors that metastasize hematogenously and thereby presents a distinct set of therapeutic challenges. A molecular level understanding of how EOC tumor cells metastasize is necessary for the development of novel therapies to inhibit ip spread and thereby improve the survival of thousands of women with EOC. PUBLIC HEALTH RELEVANCE: Development of models that accurately reflect the metastatic competence of epithelial ovarian cancer (EOC) represents a remarkable scientific challenge, because the EOC metastatic mechanism involves a novel shedding of multi-cellular aggregates (MCAs) into a cavity (peritoneal cavity) as anchorage-independent, chemotherapy-resistant spheroids. In this unique niche, molecular events that occur during the transition from free-floating MCA to life-threatening peritoneally anchored metastatic lesion are poorly understood. Understanding this transition will enable novel means of targeting intraperitoneal therapies to appropriate multicellular populations.