Elucidating the tumor suppressive effects of the sirtuin, SIRT1, in triple-negative breast cancer

阐明沉默调节蛋白 SIRT1 在三阴性乳腺癌中的肿瘤抑制作用

• 批准号: 10155077
• 负责人: James Mullmann
• 金额: $ 4.25万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-05 至 2025-09-04
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10155077
• 关键词: 3' Untranslated Regions; 3-Dimensional; Aggressive behavior; Antigens; Antisense Oligonucleotides; Binding; Binding Sites; Biological Assay; Breast Cancer Cell; Breast Cancer Model; Breast Cancer Patient; Breast Cancer cell line; Breast Epithelial Cells; Cell Line; Cell Survival; Cells; DNA Binding; Development; Disease; Down-Regulation; Enzymes; Family; Frequencies; Generations; Genetic Transcription; Hormonal; Human; Hydrolase; Link; Malignant Neoplasms; Measures; Mediating; Messenger RNA; Metastatic Neoplasm to the Lung; MicroRNAs; Modality; Modeling; Modification; Molecular; Mouse Mammary Tumor Virus; Mus; Mutate; Nature; Neoplasm Metastasis; Normal tissue morphology; Nuclear; Nucleic Acid Regulatory Sequences; Oncogenes; Pathway interactions; Patients; Pharmacology; Phenotype; Play; Polyoma Virus Middle T Staining Method; Production; Prognosis; Proteins; Proton Pump; Regulation; Research; Role; Running; SIRT1 gene; Secretory Vesicles; Sirtuins; Small RNA; System; Therapeutic; Time; Tissue-Specific Gene Expression; Training; Transcript; Transcriptional Regulation; Tumor Suppressor Proteins; Work; aggressive breast cancer; angiogenesis; breast cancer progression; cancer type; chromatin immunoprecipitation; exosome; experience; extracellular vesicles; in vivo; insight; malignant breast neoplasm; mouse model; novel; novel therapeutic intervention; overexpression; prevent; promoter; protein expression; small hairpin RNA; transcription factor; transcriptome sequencing; treatment strategy; triple-negative invasive breast carcinoma; tumor; tumor growth; tumor microenvironment; tumor progression; tumorigenesis; vacuolar H+-ATPase

Project Summary- Triple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer (BC), evades hormonal treatment modalities, and patients with TNBC experience high rates of metastasis and have a poor prognosis. Therefore, there is a critical need to find better approaches to treat TNBC. Sirtuin 1 (SIRT1) represents an interesting target in this regard, as SIRT1 has been shown to be implicated in cancer as a tumor suppressor, and in fact, SIRT1 mRNA and protein are significantly downregulated in TNBC. Previous work has shown that decreasing SIRT1 in human TNBC cells promotes the generation of a secretome containing soluble hydrolases and a large number of exosomes, a specific class of extracellular vesicles, with unique cargo. Furthermore, the hydrolases and exosomes produced by TNBC cells depleted of SIRT1 were shown to promote the aggressive phenotype of TNBC cells by promoting cell survival, invasive activity, and metastasis. Thus, it is important to determine whether decreasing SIRT1 expression or activity in vivo in mouse models of breast cancer promotes tumorigenesis and metastasis. Additionally, the mechanism for decreased expression of SIRT1 in TNBC is largely unknown, and a better understanding of SIRT1 regulation will uncover changes in cancer-promoting pathways that make TNBC so aggressive. In this proposal, the effects of decreased SIRT1 expression or activity on tumorigenesis and metastasis will be elucidated (Aim 1), and the transcriptional and post-transcriptional regulatory factors that decrease SIRT1 expression in TNBC will be identified (Aim 2). In Aim 1, three distinct, yet complementary, mouse models of breast cancer will be used to determine the effects of altered SIRT1 expression or pharmacologic modulation of SIRT1 activity on cancer progression in the tumor microenvironment, including tumor growth, invasiveness, and angiogenesis, as well as rate of metastasis. In Aim 2, precision nuclear run-on RNA sequencing (PRO-Seq) and small RNA sequencing will be performed to elucidate transcriptional and post-transcriptional regulators of SIRT1, respectively. For this aim, a system of three human BC cell lines with varying levels of SIRT1 expression will be used. Changes in transcriptional regulation and microRNA expression with PRO-Seq and small RNA-Seq, respectively, will be determined by comparing across these three cell lines. Due to the highly aggressive nature of and difficulty to treat TNBC, it is imperative to develop new therapeutic strategies that slow tumorigenesis and metastasis. Through the outlined six-year training plan in Drs. Richard Cerione and Robert Weiss’s labs, which have expertise in elucidating underlying molecular mechanisms and their effects in vivo through mouse models, by determining the effects of low SIRT1 levels in mouse models of BC and the regulatory factors that mediate this downregulation, this proposal holds promise for clarifying the role of SIRT1 as a tumor suppressor in TNBC.

项目摘要三阴性乳腺癌（TNBC），最具侵略性的乳腺癌亚型（BC）， 逃避马or的治疗方式，TNBC患者的转移率很高，并且具有 预后不佳。因此，迫切需要寻找更好的方法来治疗TNBC。 Sirtuin 1（SIRT1） 在这方面代表一个有趣的目标，因为已经证明SIRT1在癌症中实施 肿瘤抑制剂，实际上，在TNBC中，SIRT1 mRNA和蛋白质显着下调。以前的 工作表明，人类TNBC细胞中的SIRT1降低会促进分泌组的产生 包含固体水解酶和大量外泌体，一类特定的细胞外蔬菜，带有 独特的货物。此外，由SIRT1耗尽的TNBC细胞产生的水解酶和外泌体为 通过促进细胞存活，侵入性活性和 转移。这是重要的是确定在体内降低SIRT1表达或活性是在 乳腺癌的小鼠模型促进肿瘤发生和转移。另外，机制 SIRT1在TNBC中的表达降低在很大程度上是未知的，并且更好地理解了SIRT1调节 将发现促成TNBC如此侵略性的癌症促进途径的变化。在此提案中， SIRT1表达或活性降低对肿瘤发生和转移的影响将被阐明（AIM 1），，， 以及降低TNBC中SIRT1表达的转录和转录后调节因子 将被识别（AIM 2）。在AIM 1中，将是三种不同但完整的乳腺癌的小鼠模型 用于确定SIRT1表达改变或SIRT1活性的药物调制的影响 肿瘤微环境中的癌症进展，包括肿瘤生长，侵入性和血管生成， 以及转移速率。在AIM 2中，精密核跑步RNA测序（Pro-Seq）和小RNA 将进行测序以阐明SIRT1的转录和转录后调节剂 分别。为此，一个具有不同级别SIRT1表达水平的人类BC细胞系的系统将 被使用。使用Pro-Seq和小RNA-Seq的转录调控和microRNA表达的变化， 将分别通过在这三个细胞系之间进行比较来确定。由于高度侵略性 必须治疗TNBC的性质，必须制定新的治疗策略来缓慢 肿瘤发生和转移。通过概述的DRS概述的六年培训计划。理查德·塞里昂（Richard Cerione）和罗伯特（Robert） 魏斯的实验室，这些实验室在阐明潜在的分子机制及其在体内的影响方面具有专业知识 通过鼠标模型，通过确定低sirt1水平在bc和bc的鼠标模型中的影响 调解这种下调的监管因素，该提案有望阐明 SIRT1作为TNBC中的肿瘤抑制剂。