Genome-wide CRISPR Screen Reveal Targets of Chiral Gold(I) Anticancer Compound in Mammalian Cells

Metal-based drugs, such as cisplatin and auranofin, are
used for
the treatment of cancer and rheumatoid arthritis, respectively. Auranofin
and other gold-derived compounds have been shown to possess anticancer,
anti-inflammatory, antimicrobial, and antiparasitic activity in preclinical
and clinical trials. Unlike platinum agents which are known to target
DNA, the target of gold is not well elucidated. To better understand
the targets and effects of gold agents in mammalian cells, we used
a targeted CRISPR (ToxCRISPR) screen in K562 cancer cells to identify
genes that modulate cellular sensitivity to gold. We synthesized a
novel chiral gold(I) compound, JHK-21, with potent anticancer activity.
Among the most sensitizing hits were proteins involved in mitochondrial
carriers, mitochondrial metabolism, and oxidative phosphorylation.
Further analysis revealed that JHK-21 induced inner mitochondria membrane
dysfunction and modulated ATP-binding cassette subfamily member C
(ABCC1) function in a manner distinct from auranofin. Characterizing
the therapeutic effects and toxicities of metallodrugs in mammalian
cells is of growing interest to guide future drug discovery, and cellular
and preclinical/clinical studies.

金属基药物如顺铂（cisplatin）与金诺芬（auranofin），分别被用于癌症与类风湿关节炎（rheumatoid arthritis）的治疗。金诺芬与其他金基化合物在临床前及临床试验中已被证实具备抗癌、抗炎、抗菌及抗寄生虫活性。与已知以DNA为作用靶点的铂类药物不同，金类药物的作用靶点尚未被充分阐明。为更好地阐明金类药物在哺乳动物细胞中的作用靶点与效应机制，本研究在K562癌细胞中开展了靶向CRISPR（ToxCRISPR）筛选，以鉴定可调控细胞对金类药物敏感性的基因。我们合成了一种具备强效抗癌活性的新型手性金(I)化合物JHK-21。在筛选得到的最具增敏作用的命中基因中，有一类蛋白参与线粒体载体运输、线粒体代谢及氧化磷酸化过程。进一步分析显示，JHK-21可诱导线粒体内膜功能障碍，并以与金诺芬不同的方式调控ATP结合盒亚家族C成员（ABCC1）的功能。对哺乳动物细胞中金基药物的治疗效应与毒性进行表征，可为未来的药物研发、细胞实验及临床前/临床试验提供指导，相关研究的关注度正日益提升。