An epigenetic link from CXCL12-CXCR4 axis through nuclear LASP-1 in breast cancer

乳腺癌中 CXCL12-CXCR4 轴通过核 LASP-1 的表观遗传联系

基本信息

批准号：
9204937
负责人：
Dayanidhi Raman
金额：
$ 19.77万
依托单位：
UNIVERSITY OF TOLEDO HEALTH SCI CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-12-01 至 2017-11-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9204937
关键词：
AMD3100 Agar Amino Acids Anchorage-Independent Growth Antibodies Area Binding Biochemical Biological Biological Assay Bone Resorption Breast Cancer Cell Breast Cancer Patient Breast Cancer cell line Breast cancer metastasis CXC Chemokines CXCL12 gene CXCR3 gene CXCR4 gene Cancer Etiology Cell Nucleus Cell membrane Cells Cessation of life Chemotaxis Complex Computer software Confocal Microscopy Cytoplasm Dentin Dominant-Negative Mutation E-Cadherin Embryonic Development Epigenetic Process Epithelial Estrogen Receptors Event Fructose-1,6-Bisphosphatase Goals Growth Histone H3 Histones IL8RA gene IL8RB gene In Situ In Vitro Individual Knock-out Label Ligation Light Link Lysine Lytic Metastatic Lesion MDA MB 231 Maps Mediating Mesenchymal Metastatic breast cancer Methylation Molecular Mutagenesis Neoplasm Metastasis Nuclear Nucleosomes Osteolytic Parnate Peptides Phenotype Play Primary Neoplasm Proteins Proteomics Recombinants Recruitment Activity Research Resistance Role SUM-159 Breast Cancer Cell Line Shapes Site Site-Directed Mutagenesis Snails Survival Rate Testing Transforming Growth Factor beta Transforming Growth Factors Woman bone cell motility chemokine chemokine receptor chemotherapeutic agent chromatin immunoprecipitation demethylation epigenome inhibitor/antagonist knock-down malignant breast neoplasm matrigel migration mortality mutant new therapeutic target novel parathyroid hormone-related protein programs promoter public health relevance slug small molecule inhibitor stemness transcription factor triple-negative invasive breast carcinoma tumor tumor microenvironment tumor progression

项目摘要

DESCRIPTION (provided by applicant): The goal of the proposed research is to investigate the role of CXCL12-driven nuclear LASP1 in modulation of epigenetic events in breast cancer. LASP-1 mediates cell migration, proliferation and survival in several breast cancer cell lines. Silencing of LASP-1 inhibits proliferation and migration by 45%. Previously, LASP-1 was demonstrated to directly interact with CXC chemokine receptors, CXCR1, CXCR2, CXCR3 and CXCR4 that play a key role in the tumor microenvironment facilitating breast cancer progression and metastasis. In particular, LASP-1 augmented CXCR2-mediated cell migration. Epigenetic alterations in breast cancer cells convert them into aggressive and metastatic phenotype. In this study, through proteomics, UHRF1 was discovered as a novel LASP-1 associating protein. Subsequently, DNMT1, G9a and Snail1 were also observed to associate with LASP-1. In particular, Snail1 was found to directly bind to LASP-1. The biological implication of this direct interaction is unclear. First, I propose to map the interaction sites between LASP-1 and Snail1 by mutational and biochemical approaches. I further propose to study the LASP1-Snail1 complex for its ability to modulate the E-cadherin promoter. Additionally, as Snail1 directly binds to lysine demethyalse1 (LSD1), LSD1 will be analyzed whether it associates with LASP1-Snail1 complex by biochemical studies. Functionally, I propose to perform a chromatin immunoprecipitation (ChIP) analysis for LASP-1, LSD1, and K4/9 methylation of histone H3 to see if LASP-1/LSD1 co-localize to regions with demethylated histones upon stimulation with CXCL12. Alternatively, recombinant LASP-1 will be mixed with purified LSD-1 and see if LASP-1 enhances in vitro demethylation activity on labeled histone H3 or nucleosome substrates. Additionally, non-silenced and LASP1-knock down basal- like breast cancer cells will be tested for their ability to facilitate bone resorption in a dentine disk assay. LASP1-Snail1 axis would become a novel drug target for small molecule inhibitors with the aim of prolonging the survival rate especially in triple-negative breast cancer patients. Novel inhibitors might be even more useful in cases of breast cancer that are resistant to current chemotherapeutic agents.

描述（由申请人提供）：拟议研究的目标是研究 CXCL12 驱动的核 LASP1 在调节乳腺癌表观遗传事件中的作用，LASP-1 介导多种乳腺癌细胞系的细胞迁移、增殖和存活。沉默 LASP-1 可抑制 45% 的增殖和迁移此前，LASP-1 被证明可直接与 CXC 趋化因子受体 CXCR1、CXCR2 相互作用。 CXCR3 和 CXCR4 在促进乳腺癌进展和转移的肿瘤微环境中发挥着关键作用，特别是，LASP-1 增强了乳腺癌细胞中 CXCR2 介导的细胞迁移，将其转化为侵袭性和转移性表型。通过蛋白质组学，发现UHRF1是一种新的LASP-1关联蛋白，随后，DNMT1、G9a和Snail1也被观察到与LASP-1关联。特别是，Snail1 被发现直接与 LASP-1 结合，这种直接相互作用的生物学意义尚不清楚。首先，我建议通过突变和生化方法来绘制 LASP-1 和 Snail1 之间的相互作用位点。 LASP1-Snail1 复合物能够额外调节 E-钙粘蛋白启动子，因为 Snail1 直接结合。对于赖氨酸脱甲基酶1 (LSD1)，将通过生化研究分析LSD1是否与LASP1-Snail1复合物结合。在功能上，我建议对组蛋白的LASP-1、LSD1和K4/9甲基化进行染色质免疫沉淀(ChIP)分析。 H3 观察 LASP-1/LSD1 在刺激后是否共定位于具有去甲基化组蛋白的区域或者，将重组 LASP-1 与纯化的 LSD-1 混合，看看 LASP-1 是否增强标记组蛋白 H3 或核小体底物的体外去甲基化活性，以及非沉默和 LASP1 敲低的基底细胞样乳腺癌。将在牙本质盘测定中测试细胞促进骨吸收的能力，以期成为小分子抑制剂的新药物靶标。延长生存率，特别是在三阴性乳腺癌患者中，新型抑制剂可能在对现有化疗药物耐药的乳腺癌病例中更有用。