The State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing, 210023, China.
Department of Biological Science, National University of Singapore, Singapore, 117543, Singapore.
Theranostics. 2018 Jun 6;8(13):3504-3516. doi: 10.7150/thno.24336. eCollection 2018.
Many plant-specialized metabolites have remedial properties and provide an endless chemical resource for drug discovery. However, most of these metabolites have promiscuous binding targets in mammalian cells and elicit a series of responses that collectively change the physiology of the cells. To explore the potential of these multi-functional and multi-targeted drugs, it is critical to understand the direct relationships between their key chemical features, the corresponding binding targets and the relevant biological effects, which is a prerequisite for future drug modification and optimization. We introduced and demonstrated a general workflow, called Comparative Profiling of Analog Targets (CPAT), to connect specific biological effects with defined chemical structures of drugs. Using resveratrol (RSV) as an example, we have synthesized and characterized a series of partial functional analogs of RSV. An analog (named RSVN) that specifically lost the inhibitory effect of RSV in cell migration was identified. The binding targets of RSVN and RSV was profiled and compared. Comparative profiling of the RSV and RSVN binding targets showed that, unlike RSV, RSVN failed to target specific components involved in DNA methylation (histone deacetylase 1 [HDAC1] and DNA methyltransferase 3 alpha [DNMT3a]), suggesting that RSV suppresses cell migration through epigenetic regulation. Indeed, RSV treatment recruited HDAC1 and DNMT3a to the promoter region of the focal adhesion kinase (FAK), a key factor involved in cell adhesion, enhanced the promoter methylation, and thus attenuated the protein expression. The inhibitory effect of RSV in cell migration was diminished once FAK expression was restored. Thus, the mechanism of RSV in inhibiting cell migration could be largely accounted to epigenetically control of FAK expression. Our results showed that even though RSV exhibits promiscuous binding, its inhibitory effect on cell migration can be mechanistically understood. First, the presence of 4'-hydroxystilbene within the RSV structure is essential for this activity. Second, it inhibits cell migration through epigenetically based downregulation of FAK expression. Taken together, we propose that CPAT might also be adapted to delineate the specific function of other natural products (NPs) that exhibit binding promiscuity.
许多植物特有的代谢产物具有治疗特性，为药物发现提供了无尽的化学资源。然而，这些代谢产物在哺乳动物细胞中有广泛的结合靶点，并引发一系列反应，这些反应共同改变了细胞的生理学。为了探索这些多功能、多靶点药物的潜力，了解它们关键化学特征、相应的结合靶点和相关生物学效应之间的直接关系至关重要，这是未来药物修饰和优化的前提。
我们介绍并演示了一种通用的工作流程，称为类似物靶标比较分析（CPAT），将特定的生物学效应与药物的特定化学结构联系起来。以白藜芦醇（RSV）为例，我们合成并表征了一系列 RSV 的部分功能类似物。鉴定出一种特定地失去 RSV 对细胞迁移抑制作用的类似物（命名为 RSVN）。对 RSVN 和 RSV 的结合靶点进行了分析和比较。
对 RSV 和 RSVN 结合靶点的比较分析表明，与 RSV 不同，RSVN 未能靶向特定的参与 DNA 甲基化的成分（组蛋白去乙酰化酶 1[HDAC1]和 DNA 甲基转移酶 3α[DNMT3a]），表明 RSV 通过表观遗传调控抑制细胞迁移。事实上，RSV 处理使 HDAC1 和 DNMT3a 募集到参与细胞黏附的关键因子粘着斑激酶（FAK）的启动子区域，增强了启动子的甲基化，从而减弱了蛋白表达。一旦恢复 FAK 的表达，RSV 抑制细胞迁移的作用就会减弱。因此，RSV 抑制细胞迁移的机制可以在很大程度上归因于 FAK 表达的表观遗传调控。
我们的结果表明，即使 RSV 表现出广泛的结合，但其对细胞迁移的抑制作用也可以从机制上得到理解。首先，RSV 结构中的 4'-羟基二苯乙烯是这种活性所必需的。其次，它通过表观遗传下调 FAK 表达来抑制细胞迁移。总之，我们提出 CPAT 也可能适用于描绘其他表现出结合混杂性的天然产物（NPs）的特定功能。
