Screening of inhibitors of SIRT1 and SIRT2 for the prevention of neuroblastoma

筛选用于预防神经母细胞瘤的 SIRT1 和 SIRT2 抑制剂

• 批准号: 7871554
• 负责人: Tao Liu
• 金额: $ 5.4万
• 依托单位: UNIVERSITY OF NEW SOUTH WALES
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-01 至 2012-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7871554
• 关键词: Animal Cancer Model; Apoptosis; Cause of Death; Cells; Child; Clinical; CpG Islands; Deacetylation; Dose; Gene Expression; Genetic Transcription; Goals; Growth; Histone Deacetylase; Histone Deacetylation; MYC gene; Malignant Neoplasms; Mediating; Methods; Methylation; Mitogen-Activated Protein Kinases; N-Myc Protein; Neuroblastoma; Oncogene Proteins; Outcome; Phosphorylation; Play; Prevention; Prevention strategy; Protein Kinase; Protein Kinase Protein Phosphorylation; Repression; Research; Research Design; Role; Screening procedure; Serine; Signal Transduction; Solid Neoplasm; Transgenic Mice; Tumor Suppressor Proteins; Ubiquitination; cell growth; comparative efficacy; early childhood; extracellular; gene repression; inhibitor/antagonist; multicatalytic endopeptidase complex; neuroblast; promoter; protein degradation; small molecule; tumor initiation

DESCRIPTION (provided by applicant): Background: Neuroblastoma is the commonest solid tumour in early childhood. Neuroblastoma due to N-Myc oncogene amplification represents a more aggressive subtype with a worse clinical outcome. N-Myc protein is stabilized when phosphorylated at Serine 62 by extracellular signal-regulated protein kinase (ERK). The class III histone deacetylase SIRT1 induces histone deacetylation, promoter CpG island methylation, transcriptional repression, and deacetylation of tumour suppressor proteins. By blocking apoptosis and promoting cell growth, SIRT1 may play a critical role in tumour initiation and progression. Much less is known about the role of SIRT2 in cancer. Aristoforin, cambinol and tenovin-6, which are small molecule inhibitors of both SIRT1 and SIRT2, have shown promising anti-cancer effects in various animal models of cancer. We have found that N-Myc induces SIRT1 and SIRT2 over-expression in neuroblastoma cells, that SIRT1 and SIRT2 block proteasome-mediated N-Myc protein degradation, and that repression of SIRT1 or SIRT2 induces cell growth arrest. The SIRT1/SIRT2 inhibitor cambinol promotes N-Myc protein degradation and induces dose-dependant cell growth arrest. Moreover, SIRT1 and SIRT2 repress gene transcription of mitogen-activated protein kinase phosphotase 3 (MKP3), which dephosphorylates and inactivates ERK. Aims: (1) To demonstrate that SIRT1 and SIRT2 stabilize N-Myc protein by repressing MKP3 expression and modulating N-Myc protein phosphorylation; (2) To compare the efficacy of SIRT1/SIRT2 inhibitors in promoting N-Myc protein degradation and blocking proliferation and/or survival of neuroblastoma and pre-cancer neuroblast cells; (3) To identify the SIRT1/SIRT2 inhibitor of the best choice for prevention of neuroblastoma. Research design and methods: (i) Do SIRT1 and SIRT2 block N-Myc oncoprotein degradation by blocking N-Myc oncoprotein ubiquitination? (ii) Do SIRT1 and SIRT2 stabilize N-Myc oncoprotein by repressing MKP3 gene transcription, enhancing ERK phosphorylation, and consequently inducing N-Myc protein phosphorylation at Serine 62? (iii) Do SIRT1/SIRT2 inhibitors reactivate MKP3 gene expression, dephosphorylate ERK, promote N-Myc protein degradation, and induce growth arrest and/or apoptosis in neuroblastoma cells? (iv) Do SIRT1/SIRT2 inhibitors reactivate MKP3 gene expression, dephosphorylate ERK, promote N-Myc protein degradation, and induce growth arrest and/or apoptosis in pre-cancer neuroblasts from N-Myc transgenic mice? (v) To examine and compare the efficacy of SIRT1/SIRT2 inhibitors in the prevention of neuroblastoma in N- Myc transgenic mice.

描述（由申请人提供）： 背景：神经母细胞瘤是幼儿期最常见的实体瘤。 N-Myc 癌基因扩增引起的神经母细胞瘤是一种更具侵袭性的亚型，临床结果更差。 N-Myc 蛋白在丝氨酸 62 被细胞外信号调节蛋白激酶 (ERK) 磷酸化后会保持稳定。 III 类组蛋白脱乙酰酶 SIRT1 诱导组蛋白脱乙酰化、启动子 CpG 岛甲基化、转录抑制和肿瘤抑制蛋白的脱乙酰化。通过阻止细胞凋亡和促进细胞生长，SIRT1 可能在肿瘤的发生和进展中发挥关键作用。人们对 SIRT2 在癌症中的作用知之甚少。 Aristoforin、cambinol 和 tenovin-6 是 SIRT1 和 SIRT2 的小分子抑制剂，在各种癌症动物模型中显示出良好的抗癌作用。 我们发现 N-Myc 诱导神经母细胞瘤细胞中 SIRT1 和 SIRT2 过度表达，SIRT1 和 SIRT2 阻断蛋白酶体介导的 N-Myc 蛋白降解，并且 SIRT1 或 SIRT2 的抑制诱导细胞生长停滞。 SIRT1/SIRT2 抑制剂 Cambinol 可促进 N-Myc 蛋白降解并诱导剂量依赖性细胞生长停滞。此外，SIRT1 和 SIRT2 抑制丝裂原激活蛋白激酶磷酸酶 3 (MKP3) 的基因转录，从而使 ERK 去磷酸化和失活。目的：（1）证明SIRT1和SIRT2通过抑制MKP3表达和调节N-Myc蛋白磷酸化来稳定N-Myc蛋白； （2）比较SIRT1/SIRT2抑制剂促进N-Myc蛋白降解和阻断神经母细胞瘤和癌前神经母细胞增殖和/或存活的功效； (3)寻找预防神经母细胞瘤的最佳选择SIRT1/SIRT2抑制剂。研究设计和方法： (i) SIRT1 和 SIRT2 是否通过阻断 N-Myc 癌蛋白泛素化来阻断 N-Myc 癌蛋白降解？ (ii) SIRT1 和 SIRT2 是否通过抑制 MKP3 基因转录、增强 ERK 磷酸化并最终诱导 N-Myc 蛋白丝氨酸 62 磷酸化来稳定 N-Myc 癌蛋白？ (iii) SIRT1/SIRT2 抑制剂是否会重新激活 MKP3 基因表达、使 ERK 去磷酸化、促进 N-Myc 蛋白降解并诱导神经母细胞瘤细胞生长停滞和/或凋亡？ (iv) SIRT1/SIRT2 抑制剂是否会重新激活 N-Myc 转基因小鼠的癌前神经母细胞中的 MKP3 基因表达、使 ERK 去磷酸化、促进 N-Myc 蛋白降解并诱导生长停滞和/或凋亡？ (v)检查并比较SIRT1/SIRT2抑制剂在预防N-Myc转基因小鼠中神经母细胞瘤中的功效。