The Role of CCN5 in Progression of Breast Cancer

描述(由申请人提供)： 乳腺癌是一种遗传异质性疾病，是西方女性中最常见的恶性疾病，仅次于非黑色素细胞皮肤癌。它攻击八分之一的女性(约12%)，影响到世界上几乎每个家庭，包括美国退伍军人人口。大约30%的确诊患者会发展为侵袭性疾病，最终是无法治愈的。因此，这是女性退伍军人的一个主要健康问题。虽然早期诊断的增加和新的治疗方案显著提高了BC的存活率，但晚期BC的治疗选择有限。这些方案无效的一个原因是它们不针对肿瘤微环境，而微环境在肿瘤进展中起着关键作用。因此，有必要从非侵入性微环境中了解BC进展的病因，并利用这种认识来设计有针对性的、基于分子的治疗方法。我们最近发现，基质细胞蛋白CCN5在非侵袭性BC细胞系和组织标本中的表达高于侵袭性BC细胞系和组织标本，并在体外发挥负调控作用。它可以防止上皮细胞 BC细胞间充质转化(EMT)过程。此外，初步研究表明，CCN5可能通过保护生物屏障(肌上皮层和基底膜)来抑制原位导管癌(DCIS)向侵袭性BC的转化，或者可能阻止或减少侵袭性BC细胞的生长，或者两者兼而有之，并可能使ER阴性的侵袭性BC细胞对激素治疗敏感。现在，我们建议建立上述前提，并通过异种移植模型、基因工程小鼠模型、基因操纵的人BC细胞系和基质细胞来揭示CCN5调控癌细胞向侵袭发展的机制。为了验证这一假设，我们提出了三个特定的目标：目标1：我们将确定CCN5是否能够通过保护肌上皮层或基底膜降解或两者兼而有之来阻止DCIS向浸润性导管癌的转变。为了验证这一点，条件击倒策略将用于MCFDCIS-导管内-异种移植模型(Mind模型)。目的2：探讨CCN5对BC肿瘤进展和生存的影响。为了验证这一点，我们将使用MMTV-neu/Tet-op-MMTV-CCN5(MNIC5)转基因小鼠模型来评估CCN5基因的获得在HER-2/neu驱动的乳腺肿瘤发生中的影响。目的3：我们将确定CCN5的获得是否使抗雌激素对BC的作用重新增敏。将使用体外和体内(异种移植和MNIC5小鼠模型)。我们将使用最先进的技术、我们开发的Tet-op-MMTV-CCN5小鼠模型以及我们多学科团队的独特集体专业知识来揭示CCN5途径在BC进展中的作用。意义：拟议的研究应该对CCN5信号在浸润性癌症微环境中的保护作用做出新的解释。此外，这项研究应该阐明CCN5的功能作用，同时揭示新的靶点和途径，这将有助于我们的研究目标，即寻找有效的治疗试剂来对抗乳腺癌，为美国退伍军人和其他绝经前和绝经后的患者带来改善预后。

DESCRIPTION (provided by applicant): Breast cancer (BC), a genetically heterogeneous disease, is the most commonly identified malignant disease in Western women after non-melanocytic skin cancer. It attacks one in eight women (~12%), impacting nearly every family worldwide, including the US Veterans population. Approximately 30% of those diagnosed will develop the invasive form of the disease, which is ultimately incurable. Therefore, it is a major health issue for women Veterans. Although increased early diagnosis and new therapeutic regimens have significantly improved BC survival, the therapeutic options for advanced stage BC are limited. One reason these regimens are not effective is that they do not target the tumor microenvironment, which plays critical roles in tumor progression. Thus, there is a need to understand the etiology of BC progression from a non- invasive microenvironment and to use this awareness for the design of a targeted, molecular based therapy. We recently discovered that the matricellular protein CCN5 is highly expressed in non-invasive BC cell lines and tissue samples, as compared to invasive ones and plays a negative regulator of plasticity in vitro. It prevents the epithelial to mesenchymal transition (EMT) process in BC cells. Furthermore, preliminary studies suggest that CCN5 may inhibit the transition of in situ ductal carcinoma (DCIS) to invasive BC through the protection of biological fences (myoepithelial layer and basement membrane), or may prevent or reduce the growth of aggressive BC cells or both and possibly make ER negative aggressive BC cells sensitive to hormone therapy. Now, we propose to establish the above premises and unravel the mechanisms of CCN5 in regulation of cancer cell progression to invasion using a xenograft model, genetically engineered mouse models, genetically manipulated human BC cell lines and stromal cells. To test this hypothesis, three specific aims are proposed: Aim 1: We will determine whether CCN5 is able to prevent DCIS to invasive ductal carcinoma transition by protecting the myoepithelial layer or basement membrane degradation or both. To test this, conditional knock- down strategies will be used in a MCFDCIS-intraductal-xenograft model (MIND model). Aim 2: We will determine the effect of CCN5 on tumor progression and survival in BC. To test this, we will use the MMTV-neu/Tet-op-MMTV-CCN5 (MNIC5) transgenic mouse model to evaluate the impact of CCN5 gains in HER-2/neu driven mammary tumorigenesis. Aim 3: We will determine whether the gain of CCN5 re-sensitizes antiestrogen's action on BC. Both in vitro and in vivo (xenografts and MNIC5 mouse model) will be used. We will use state-of-the art techniques, our development of a Tet-op-MMTV-CCN5 mouse model, and the unique collective expertise of our multi-disciplinary team to uncover the role of the CCN5 pathway in BC progression. Significance: The proposed studies should result in new explanations of the protective role of CCN5 signaling in microenvironment of invasive cancers. Moreover, this study should clarify the functional roles of CCN5, while revealing novel targets and pathways which will aid in our research goals of finding effective therapeutic reagents to battle breast cancer bringing an improved prognosis to US Veterans and other pre- and post- menopausal patients.