PDF(Pubmed)
Abstract：
Macropinocytosis is a cellular process that enables cells to engulf extracellular material, such as nutrients, growth factors, and even whole cells. It is involved in several physiological functions as well as pathological conditions. In cancer cells, macropinocytosis plays a crucial role in promoting tumor growth and survival under nutrient-limited conditions. In particular KRAS mutations have been identified as main drivers of macropinocytosis in pancreatic, breast, and non-small cell lung cancers. We performed a high-content screening to identify inhibitors of macropinocytosis in pancreatic ductal adenocarcinoma (PDAC)-derived cells, aiming to prevent nutrient scavenging of PDAC tumors. The screening campaign was conducted in a well-known pancreatic KRAS-mutated cell line (MIAPaCa-2) cultured under nutrient deprivation and using FITC-dextran to precisely quantify macropinocytosis. We assembled a collection of 3584 small molecules, including drugs approved by the Food and Drug Administration (FDA), drug-like molecules against molecular targets, kinase-targeted compounds, and molecules designed to hamper protein-protein interactions. We identified 28 molecules that inhibited macropinocytosis, with potency ranging from 0.4 to 29.9 μM (EC50). A few of them interfered with other endocytic pathways, while 11 compounds did not and were therefore considered specific \"bona fide\" macropinocytosis inhibitors and further characterized. Four compounds (Ivermectin, Tyrphostin A9, LY2090314, and Pyrvinium Pamoate) selectively hampered nutrient scavenging in KRAS-mutated cancer cells. Their ability to impair albumin-dependent proliferation was replicated both in different 2D cell culture systems and 3D organotypic models. These findings provide a new set of compounds specifically targeting macropinocytosis, which could have therapeutic applications in cancer and infectious diseases.
摘要：
巨噬细胞增多是一个细胞过程，使细胞吞噬细胞外物质，如营养素，生长因子，甚至整个细胞。它涉及几种生理功能以及病理状况。在癌细胞中，在营养有限的条件下，巨噬细胞增多在促进肿瘤生长和存活中起着至关重要的作用。特别是KRAS突变已被确定为胰腺巨噬细胞增多的主要驱动因素，乳房,和非小细胞肺癌。我们进行了高含量筛选，以鉴定胰腺导管腺癌（PDAC）衍生细胞中巨细胞增多症的抑制剂，旨在防止PDAC肿瘤的营养清除。筛选活动是在众所周知的胰腺KRAS突变细胞系（MIAPaCa-2）中进行的，该细胞系在营养匮乏的情况下培养，并使用FITC-葡聚糖精确定量巨噬细胞吞噬。我们组装了3584个小分子，包括食品和药物管理局（FDA）批准的药物，针对分子靶标的药物样分子，激酶靶向化合物，和旨在阻碍蛋白质-蛋白质相互作用的分子。我们确定了28种抑制巨噬细胞增多的分子，效力范围为0.4至29.9μM（EC50）。其中一些干扰了其他内吞途径，而11种化合物没有，因此被认为是特异性的“真正的”巨细胞增生抑制剂，并进一步表征。四个化合物（伊维菌素，TyrphostinA9，LY2090314和PyrviniumPamate）选择性地阻碍了KRAS突变的癌细胞中的营养清除。它们削弱白蛋白依赖性增殖的能力在不同的2D细胞培养系统和3D器官型模型中都得到了复制。这些发现提供了一组专门针对巨噬细胞增多症的新化合物，可以在癌症和传染病中具有治疗性应用。
