Abstract
Liver cancer treatment with cisplatin is often hindered by drug resistance. This study aimed to identify key genes associated with cisplatin resistance in liver cancer and develop targeted inhibitors. Using genome-wide CRISPR-Cas9 screening, ATOX1 was identified as a critical gene for cisplatin resistance. ATOX1 was highly expressed in liver cancer tissues and associated with poor prognosis. Knockdown of ATOX1 in liver cancer cells enhanced cisplatin sensitivity in vitro and in vivo. Molecular dynamics simulation and virtual screening identified compound 8 as a potent ATOX1 inhibitor with high affinity (Kd = 12.5 μM) and exhibited synergistic effects with cisplatin on liver cancer cell growth. Mechanistically, compound 8 inhibits the activity of ATOX1, leading to intracellular copper accumulation. The elevated copper levels subsequently promote increased DNA methylation at the NOTCH1 promoter, resulting in suppression of the NOTCH1/HES1 signaling pathway and enhancing the sensitivity of liver cancer cells to cisplatin. In conclusion, ATOX1 is crucial for cisplatin resistance in liver cancer and linked to poor prognosis. Targeting ATOX1 with compound 8 may be a novel therapeutic strategy for overcoming cisplatin resistance.
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Data availability
The raw FASTQ files from the CRISPR/Cas9 library screen and RNA-seq have been deposited in the CNCB database (https://www.cncb.ac.cn/) under accession number PRJCA056149. All other raw data are provided in the Supplementary Data and are available from the corresponding author upon reasonable request.
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Acknowledgements
This research was financially supported by the National Natural Science Foundation of China (82560795, 82260535), Guizhou Provincial Science and Technology Projects General (ZK[2026]341). We would like to thank the Figdraw platform (https://www.figdraw.com/#/) for providing the original materials and authorization approval for the creation of the schematic diagrams for Figs. 1A and 5G. The authorization approval numbers are TWWYA9335b and UWPIIde6be, respectively.
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Dan Ma, Shi Zuo, Lei Tang, and Zhirui Zeng designed or supported the research and revised the manuscript. Chujiao Hu wrote the paper. Chujiao Hu, Huading Tai, Renguang Zhu, and Zhirui Zeng performed the research and analyzed the data. Chujiao Hu, Huading Tai, Renguang Zhu, Zhirui Zeng, Zhengyu Shu, and Guanghao Guo participated in animal experiments. All the authors have read and approved the final version of the manuscript.
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Hu, C., Tai, H., Zhu, R. et al. CRISPR-Cas9 screening identifies ATOX1-driven cisplatin resistance mechanisms in liver cancer and evaluates targeted inhibitor efficacy. Commun Biol (2026). https://doi.org/10.1038/s42003-026-09722-8
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DOI: https://doi.org/10.1038/s42003-026-09722-8
