Anthrax Toxin Receptor as a marker and target of breast cancer stem cells

炭疽毒素受体作为乳腺癌干细胞的标记和靶标

基本信息

批准号：
8113776
负责人：
Harikrishna Nakshatri
金额：
$ 20.1万
依托单位：
INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-03-17 至 2013-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8113776
关键词：
Affinity Archives Basal Cell Binding Biological Assay Biological Markers Breast Breast Cancer Cell CD44 gene Cancer cell line Cancerous Cell division Cell surface Cells Cleaved cell Collagen Data Set Disease Drug resistance Dyes Endothelial Cells Epithelial Epithelial Cells Estrogen Antagonists Extracellular Domain Future Gene Expression Genes Heterogeneity Immunohistochemistry In Vitro Ligands Malignant Neoplasms Mammary Neoplasms Mammary gland Matrix Metalloproteinases Measures Mediating Molecular Profiling NOD/SCID mouse Neoplasm Metastasis Nodal Normal Cell Nuclear Nuclear Receptors Outcome PKH 26 Pathway interactions Patients Pharmaceutical Preparations Phenotype Phosphorylation Play Property Radiation Recurrence Reporting Resistance Role Signal Transduction Solid Neoplasm Stem cells TACSTD2 gene Testing Tumorigenicity Up-Regulation Urokinase aldehyde dehydrogenase 1 aldehyde dehydrogenases anthrax lethal factor anthrax protective factor anthrax toxin anthrax toxin receptors base cancer cell cancer stem cell cell transformation cell type chemotherapy cohort conventional therapy cytotoxic docetaxel epithelial to mesenchymal transition hormone therapy in vivo inhibitor/antagonist lipoprotein receptor-related protein 6 malignant breast neoplasm multicatalytic endopeptidase complex mutant neoplastic cell overexpression progenitor radiation resistance response self-renewal small hairpin RNA small molecule stem stemness stromelysin 3 therapeutic target therapy development tumor v-src Oncogenes

项目摘要

DESCRIPTION (provided by applicant): Breast cancer cells with the cell surface marker expression profile of CD44? or expressing higher levels of aldehyde dehydrogenase 1 are described as cancer stem cells (CSCs). Recent studies have identified additional markers that can further distinguish multiple subpopulations of CD44? cells that are resistant to radiation or chemotherapy. For example, CD44? cells retaining higher levels of the dye PKH26 after cell division or with lower proteosome activity are resistant to radiation. CD44? cells expressing mammosphere-enriched genes are resistant to anti-estrogen and chemotherapies. Despite this enormous progress, very few CSC markers are direct therapeutic targets. Therefore, further refining of CD44? cells based on additional markers is essential to characterize and target intrinsically drug-resistant or metastasis-prone cancer cells. Our studies have identified a subpopulation of CD44? cells enriched for the expression of anthrax toxin receptor 1 (ANTXR1). ANTXR1 was also elevated in primary breast epithelial cells with stem cell phenotype compared to luminal progenitor or mature cells. Only a subpopulation of breast cancer cells in primary breast cancer expresses ANTXR1. Activation of ANTXR1 through its natural ligand C5A increased Wnt activity as measured by phosphorylation of GSK3 and increased mammosphere formation. Based on these observations, we hypothesize that ANTXR1 is a functional marker of CSCs/drug-resistant cancer cells that controls self-renewal of CSCs through Wnt pathway. Two aims are proposed: 1) Disrupt ANTXR1 signaling in normal and cancerous breast epithelial cells and investigate stemness and sensitivity to chemotherapy. 2) Investigate whether ANTXR1-positive cells are enriched for Wnt activity in breast cancers and whether co- expression of ANTXR1 and Wnt pathway molecules in cancer cells is associated with disease parameters. For the first aim, we will use ANTXR1 antagonists such as mutant anthrax protective antigen with high affinity for ANTXR1 or soluble extracellular domain of ANTXR1 to investigate the effects on mammosphere forming ability, self-renewal and sensitivity to the chemotherapeutic drug docetaxel both in vitro and in vivo. In the second aim, we will determine ANTXR1, phospho-LRP6 (Wnt receptor) and nuclear 2-catenin expression by immunohistochemistry in primary breast cancers and correlate the expression with breast cancer subtypes, nodal status, grade, and the Oncotype DX recurrence score. Results of this study will have a significant impact in predicting response to conventional therapy as well as developing therapies against drug-resistant breast cancer. Prior studies on ANTXR1 in cancer were focused mainly on tumor-associated endothelial cells. This study will delineate its function in cancer cells in the context of CSC hypothesis as well as Wnt pathway modulation in cancer cells. Based on the results, future R01 type proposals will be developed, which will focus on small molecules that bind to ANTXR1:LRP6 and inhibit Wnt signaling in cancer cells. PUBLIC HEALTH RELEVANCE: This proposal will determine the role of anthrax toxin receptor 1 (ANTXR1) in breast cancer stem cells. ANTXR1 is expressed at a higher level in breast cancer stem cells compared to mature cells and may control the function of Wnt pathway in cancer stem cells. Inhibitors of ANTXR1, such as mutant protective antigen of anthrax or soluble ANTXR1 may inhibit ANTXR1 activity and sensitize cancer stem cells to chemotherapy.

描述（由申请人提供）：具有CD44细胞表面标志物表达谱的乳腺癌细胞？或表达较高水平的乙醛脱氢酶 1 被描述为癌症干细胞 (CSC)。最近的研究已经确定了额外的标记，可以进一步区分 CD44 的多个亚群？对放射或化疗有抵抗力的细胞。例如CD44？细胞分裂后保留较高水平的染料 PKH26 或具有较低蛋白体活性的细胞对辐射具有抵抗力。 CD44？表达富含乳腺球的基因的细胞对抗雌激素和化疗具有抵抗力。尽管取得了巨大进展，但很少有 CSC 标志物是直接治疗靶点。因此，进一步精制CD44？基于额外标记的细胞对于表征和靶向本质上耐药或易于转移的癌细胞至关重要。我们的研究已经确定了 CD44 的一个亚群？细胞富含炭疽毒素受体 1 (ANTXR1) 的表达。与管腔祖细胞或成熟细胞相比，具有干细胞表型的原代乳腺上皮细胞中的 ANTXR1 也升高。原发性乳腺癌中只有一部分乳腺癌细胞表达 ANTXR1。通过其天然配体 C5A 激活 ANTXR1 会增加 Wnt 活性（通过 GSK3 磷酸化和增加乳腺球形成来测量）。基于这些观察，我们假设 ANTXR1 是 CSCs/耐药癌细胞的功能标志物，通过 Wnt 途径控制 CSCs 的自我更新。提出了两个目标：1) 破坏正常和癌性乳腺上皮细胞中的 ANTXR1 信号传导，并研究干性和对化疗的敏感性。 2) 研究乳腺癌中 ANTXR1 阳性细胞的 Wnt 活性是否富集，以及癌细胞中 ANTXR1 和 Wnt 通路分子的共表达是否与疾病参数相关。第一个目标，我们将使用ANTXR1拮抗剂，例如对ANTXR1具有高亲和力的突变型炭疽保护性抗原或ANTXR1的可溶性胞外结构域，在体外和体外研究对乳腺球形成能力、自我更新和对化疗药物多西紫杉醇敏感性的影响。体内。在第二个目标中，我们将通过免疫组织化学测定原发性乳腺癌中 ANTXR1、磷酸化 LRP6（Wnt 受体）和核 2-catenin 的表达，并将表达与乳腺癌亚型、淋巴结状态、分级和 Oncotype DX 复发评分相关联。这项研究的结果将对预测传统疗法的反应以及开发针对耐药乳腺癌的疗法产生重大影响。先前关于 ANTXR1 在癌症中的研究主要集中在肿瘤相关的内皮细胞。这项研究将在 CSC 假说以及癌细胞中 Wnt 通路调节的背景下描述其在癌细胞中的功能。根据这些结果，未来将开发 R01 型提案，重点关注与 ANTXR1:LRP6 结合并抑制癌细胞中 Wnt 信号传导的小分子。公共健康相关性：该提案将确定炭疽毒素受体 1 (ANTXR1) 在乳腺癌干细胞中的作用。与成熟细胞相比，ANTXR1 在乳腺癌干细胞中的表达水平较高，并且可能控制癌症干细胞中 Wnt 通路的功能。 ANTXR1 抑制剂，例如炭疽突变保护性抗原或可溶性 ANTXR1，可能会抑制 ANTXR1 活性并使癌症干细胞对化疗敏感。