METTL16 S-glutathionylation-triggered RNA m6A modification of IGF2BP3 inhibits CFTR expression and promotes chemoresistance in colorectal cancer

  • Acta Pharmacol Sin. 2026 May 20. doi: 10.1038/s41401-026-01821-w.
Lu Xu  #  1  2  3 ,  Yan Ma  #  1 ,  Wang Yao  1 ,  Ya-Ju Qiu  1 ,  Chao Xu  1  3  4  5 ,  Fang-Yue Xu  1  6 ,  Zhi-Miao Zou  1  7 ,  Wu-Min Dai  1  7 ,  Wan-Gang Gong  1 ,  De-Ning Ma  1 ,  Xiao-Wan Chen  1  8 ,  Wen-Kai Ye  1  6 ,  Yi-Yun Huang  1  6 ,  Hai-Tao Chen  1  3  4  5 ,  Lue Hong  1  9 ,  Jia-Ping Mo  1 ,  Jian-Guo Feng  1  7 ,  En-Yan Yu  1 ,  Wei Chen  10  11  12 ,  Yu-Hua Zhang  13  14 ,  Qing-Hua Yao  15  16  17  18  19 ,  Xia Li  20  21  22  23
Affiliations
  • 1. Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, 310022, China.
  • 2. State Key Laboratory of Quality Research in Chinese Medicine & Faculty of Chinese Medicine, Macau University of Science and Technology, Macao, 999078, China.
  • 3. Department of Oncology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Xinhua Hospital of Zhejiang Province, Hangzhou, 310005, China.
  • 4. Key Laboratory for Research on the Pathogenesis of 'Inflammation-Cancer Transformation' in Intestinal Diseases, Hangzhou, 310005, China.
  • 5. Zhejiang Engineering Research Center of Intelligent Equipment of Chronic Chinese and Western Medicine, Hangzhou, 310005, China.
  • 6. The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China.
  • 7. Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, 310022, China.
  • 8. Postgraduate Training Base Alliance of Wenzhou Medical University (Zhejiang Cancer Hospital), Hangzhou, 310022, China.
  • 9. The First School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China.
  • 10. Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, 310022, China. [email protected].
  • 11. Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, 310022, China. [email protected].
  • 12. Postgraduate Training Base Alliance of Wenzhou Medical University (Zhejiang Cancer Hospital), Hangzhou, 310022, China. [email protected].
  • 13. Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, 310022, China. [email protected].
  • 14. The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China. [email protected].
  • 15. Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, 310022, China. [email protected].
  • 16. State Key Laboratory of Quality Research in Chinese Medicine & Faculty of Chinese Medicine, Macau University of Science and Technology, Macao, 999078, China. [email protected].
  • 17. Department of Oncology, The Second Affiliated Hospital of Zhejiang Chinese Medical University, Xinhua Hospital of Zhejiang Province, Hangzhou, 310005, China. [email protected].
  • 18. Key Laboratory for Research on the Pathogenesis of 'Inflammation-Cancer Transformation' in Intestinal Diseases, Hangzhou, 310005, China. [email protected].
  • 19. Zhejiang Engineering Research Center of Intelligent Equipment of Chronic Chinese and Western Medicine, Hangzhou, 310005, China. [email protected].
  • 20. Zhejiang Cancer Hospital, Hangzhou Institute of Medicine (HIM), Chinese Academy of Sciences, Hangzhou, 310022, China. [email protected].
  • 21. The Second School of Clinical Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, China. [email protected].
  • 22. Zhejiang Cancer Research Institute, Zhejiang Cancer Hospital, Hangzhou, 310022, China. [email protected].
  • 23. Postgraduate Training Base Alliance of Wenzhou Medical University (Zhejiang Cancer Hospital), Hangzhou, 310022, China. [email protected].
  • # Contributed equally.
PMID: 42162313 DOI: 10.1038/s41401-026-01821-w
Abstract

5-Fluorouracil (5-FU) resistance in colorectal Cancer (CRC) involves oxidative stress mechanisms, but the role of epitranscriptomic regulation remains unclear. This study investigates how oxidative post-translational modifications of the N6-methyladenosine (m6A) methyltransferase METTL16 contribute to 5-FU resistance. Parental (HCT8, HCT15) and 5-FU-resistant CRC cells were compared using redox proteomics, m6A-seq, RNA-seq, and functional assays. METTL16 S-glutathionylation was assessed via streptavidin pulldown and mass spectrometry. IGF2BP3's role was validated through knockdown/overexpression, patient-derived organoids (PDOs), and xenograft models. Clinical relevance was evaluated in 112 CRC patient tissues and data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Drug synergy was tested using isoliquiritigenin (ISO) combined with 5-FU. Resistant cells exhibited elevated global protein S-glutathionylation and reduced m6A RNA methylation. METTL16 underwent site-specific S-glutathionylation at Cys548, leading to its degradation and subsequent m6A loss. Integrative omics identified IGF2BP3 as a key METTL16 target: reduced m6A on IGF2BP3 mRNA enhanced its nuclear export, splicing, and overexpression. IGF2BP3 knockdown sensitized resistant cells to 5-FU in vitro and in vivo, while overexpression conferred resistance. Mechanistically, IGF2BP3 destabilized CFTR mRNA (an ABC transporter), reducing 5-FU uptake. Clinically, high IGF2BP3 correlated with poor survival and 5-FU resistance in CRC patients. Targeting IGF2BP3 with ISO synergized with 5-FU, overcoming resistance in cells and xenografts. Oxidative stress-induced METTL16 S-glutathionylation drives 5-FU resistance by reducing m6A modification, enabling IGF2BP3 overexpression and CFTR suppression. IGF2BP3 is a biomarker of clinical resistance, and its targeting with ISO represents a promising combinatorial strategy to restore 5-FU efficacy in CRC.

Keywords
CFTR; IGF2BP3; METTL16; S-glutathionylation; colorectal cancer; isoliquiritigenin.
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