Abstract

Multi-target inhibitors are currently trending in the pharmaceutical research, as they possess increased efficacy and reduced toxicity. In this study multi-target inhibitors for breast cancer are explored from a curated list of natural products, i.e. 4,670 phytochemicals belonging to 360 medicinal plants. In-silico screening of phytochemicals using SeeSAR and AutoDock Vina resulted in identification of Stearyl Palmitate as a potential drug molecule that inhibits three drug targets, i.e. HER-2, MEK-1 and PARP-1 proteins. Molecular Dynamics Simulation for 100 ns each for these three protein-ligand complexes using Desmond, Maestro platform also confirmed the prediction of multi-target inhibition by Stearyl Palmitate. Further in-vitro MTT assay demonstrated that Stearyl Palmitate has a significant IC₅₀ value of 40 µM against MCF-7 cells and >1000 µM against L929 cells. This confirmed that Stearyl Palmitate is having selective cytotoxicity towards breast cancer cells in comparison to non-cancerous cells. Fluorescence staining and flow cytometry analysis confirmed that, Stearyl Palmitate is inducing apoptosis in MCF-7 cells at IC₅₀ concentration. Finally, in-vivo efficacy and toxicity studies were performed using zebrafishes (Danio rerio). It was observed that the fishes treated with IC₅₀ concentration of Stearyl Palmitate demonstrated 2x folds reduction in tumour size, while double dose resulted in 4x folds reduction in tumour size. Stearyl Palmitate did not demonstrate any toxicity or side effects in the zebrafishes. It is concluded that, Stearyl Palmitate, a phytochemical reported to be present in Althea officinalis is a potential anti-breast cancer agent, with ability to inhibit multiple targets such as HER-2, MEK-1 and PARP-2 proteins.

Communicated by Ramaswamy H. Sarma

摘要

多靶点抑制剂目前是药物研究的趋势，因为它们具有更高的功效和更低的毒性。在这项研究中，从一系列天然产物（即属于 360 种药用植物的 4,670 种植物化学物质）中探索乳腺癌的多靶点抑制剂。使用 SeeSAR 和 AutoDock Vina 对植物化学物质进行计算机筛选，结果发现硬脂酰棕榈酸酯是一种潜在的药物分子，可抑制三种药物靶标，即 HER-2、MEK-1 和 PARP-1 蛋白。使用 Desmond、Maestro 平台对这三种蛋白质-配体复合物进行 100 ns 的分子动力学模拟，也证实了硬脂酰棕榈酸酯多靶点抑制的预测。进一步的体外 MTT 测定表明，硬脂酰棕榈酸酯对 MCF-7 细胞具有 40 µM 的显着 IC _{50值，对 L929 细胞具有 >1000 µM 的 IC 50 值。}这证实了与非癌细胞相比，硬脂基棕榈酸酯对乳腺癌细胞具有选择性细胞毒性。荧光染色和流式细胞仪分析证实，硬脂酰棕榈酸酯在IC ₅₀浓度下可诱导MCF-7细胞凋亡。最后，使用斑马鱼（ Danio rerio ）进行体内功效和毒性研究。据观察，用IC ₅₀浓度的棕榈酸硬脂酯处理的鱼表现出肿瘤大小减少了2倍，而双倍剂量导致肿瘤大小减少了4倍。棕榈酸硬脂酯没有在斑马鱼中表现出任何毒性或副作用。结论是，硬脂酰棕榈酸酯（据报道存在于木槿花中的一种植物化学物质）是一种潜在的抗乳腺癌药物，能够抑制多种靶标，例如 HER-2、MEK-1 和 PARP-2 蛋白。

拉马斯瓦米·萨尔马 (Ramaswamy H. Sarma) 通讯