高通量筛选溴结构域蛋白4的选择性多肽抑制剂及其在抗癌和蛋白检测方面的应用

Bromodomain, as the “reader” of the lysine acetylation in histone proteins and also as one of the most important molecular mechanisms in epigenetics, are linked to the regulation of gene expression and function and are also relevant to the progress of many diseases. Among Bromodomain families, BRD4 has been proved to be one of potential and very important drug targets for drug research and developments. BRD4 inhibitors can be used to treat different kinds of diseases including cancer and inflammation. However, the obvious and common limitations for current small molecule based non-peptide inhibitors include lack of selectivity and inhibition activity, which can be further improved. To answer these scientific questions, based on the natural advantages of peptide in terms of binding selectivity and also our previous relevant studies in this research area, we will perform the studies as below: (1) By using the high-throughput screening technologies (One-Bead-One-Compound (OBOC) and microarray), identify peptide inhibitors against BRD4 with good selectivity and high binding against BRD4 and obtain the improved and selective peptide amino acid sequences; (2) Further explore and investigate the anti-cancer activities (such as Lung cancer and breast cancer etc.) with good lead peptide inhibitors candidates; (3) Design , synthesize and apply these selective peptide-derived environmental responsive bioprobes for protein capturing and detection agents for BRD4.

组蛋白的赖氨酸乙酰化的“阅读器”—溴结构域蛋白(Bromodomain)，是表观遗传学中重要的分子机制之一，调控基因的表达与功能，与多种疾病发生、发展密切相关。在溴结构域蛋白家族中, BRD4已经被作为一种重要的药物靶标，其抑制剂可被发展用来治疗各种疾病 (包括癌症和炎症等)。现有的BRD4小分子抑制剂共同的弱点是不能很好区分BRD4和它的同源蛋白，选择性较差，以及抑制剂的抗癌活性有待改进。为了获得更佳选择性和活性的BRD4 抑制剂，基于多肽展现的选择性优势和申请人的前期工作基础，本项目拟开展: (1)运用高通量筛选方法 (OBOC 和微阵列), 筛选出高选择性和高亲和力结合BRD4的多肽抑制剂和优化选择性多肽的氨基酸序列; (2)进一步探索先导多肽抑制剂的抗癌活性 (如肺癌和乳腺癌等); (3)基于这些选择性多肽设计合成相应的生物探针应用于BRD4蛋白捕获和灵敏检测。

为实现靶向治疗，减少癌症病人在治疗阶段的不良反应，本研究针对相关肿瘤靶点进行高通量多肽药物筛选，期望研发灵敏的诊断试剂盒用于癌症的早期诊断或者研发出更有效和更专一的抗癌药物用于癌症疾病的治疗。组蛋白乙酰化赖氨酸的“阅读器”—溴结构域蛋白(Bromodomains)，是表观遗传学中重要的分子机制之一，调控基因的表达与功能，与多种疾病发生、发展密切相关。在溴结构域蛋白家族中，BRD4作为一种重要的药物靶标，已被证实与多种肿瘤与炎症的发病机制相关，且在肿瘤细胞内高表达。研究证实针对BRD4的抑制剂，可被发展用来治疗各种疾病(包括癌症和炎症等)。因此本研究期望开发出靶向BRD4蛋白具有抗癌活性的多肽序列。. 本研究采用OBOC（One-Bead-One-Compound，一珠一化合物）筛选方法，设计多肽序列库。通过高通量筛选技术针对BRD4（Bromodomain-4）蛋白进行靶向乙酰化先导多肽筛选，并对乙酰化先导多肽及其相应探针在抗癌和蛋白检测中的应用进行研究。. 本研究完成了组合多肽库的构建，并通过OBOC高通量筛选方法筛选出特异性靶向BRD4蛋白的先导多肽抑制剂，从中发现了具有抗癌活性的序列，有望发展成具有抗癌潜能的多肽类药物。