Identification of compound CA-5f as a novel late-stage autophagy inhibitor with potent anti-tumor effect against non-small cell lung cancer

作者：Lu Zhang, Pengfei Qiang, J. Yu, Yiming Miao, Zhiqiang Chen, Ju Qu, Qianbing Zhao, Zhuo Chen, Yachao Liu, Xin Yao, Bin Liu, Liuqing Cui, Hongjuan Jing, Gang‐Chun Sun · 发表于：Autophagy · 年份：2018 · DOI：10.1080/15548627.2018.1511503 · 被引用次数：78 · 研究领域：Autophagy in Disease and Therapy、Genomics, phytochemicals, and oxidative stress、Sirtuins and Resveratrol in Medicine

Currently, particular focus is placed on the implication of autophagy in a variety of human diseases, including cancer. Discovery of small-molecule modulators of autophagy as well as their potential use as anti-cancer therapeutic agents would be of great significance. To this end, a series of curcumin analogs previously synthesized in our laboratory were screened. Among these compounds, (3E,5E)-3-(3,4-dimethoxybenzylidene)-5-[(1H-indol-3-yl)methylene]-1-methylpiperidin-4-one (CA-5f) was identified as a potent late-stage macroautophagy/autophagy inhibitor via inhibiting autophagosome-lysosome fusion. We found that CA-5f neither impaired the hydrolytic function nor the quantity of lysosomes. Use of an isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomic screen in combination with bioinformatics analysis suggested that treatment of human umbilical vein endothelial cells (HUVECs) with CA-5f for 1 h suppressed the levels of cytoskeletal proteins and membrane traffic proteins. Subsequent studies showed that CA-5f exhibited strong cytotoxicity against A549 non-small cell lung cancer (NSCLC) cells, but low cytotoxicity to normal human umbilical vein endothelial cells (HUVECs), by increasing mitochondrial-derived reactive oxygen species (ROS) production. Moreover, CA-5f effectively suppressed the growth of A549 lung cancer xenograft as a single agent with an excellent tolerance in vivo. Results from western blot, immunofluorescence, and TdT-mediated dUTP nick en...