METTL1/WDR4-mediated m7G Hypermethylation of SCLT1 mRNA Promotes Gefitinib Resistance in Non-small Cell Lung Cancer

Zhou, S.; Wang, Y.; Wei, J.; An, K.; Shi, Y.; Zhang, X.; Wang, H.; Feng, L.; He, L.; Zhang, Y.; Ren, T.; Li, O.; Yang, Y.-G.; Kan, Q.; Tian, X.

doi:10.1101/2025.03.26.645570

bioRxiv · 10.1101/2025.03.26.645570

METTL1/WDR4-mediated m7G Hypermethylation of SCLT1 mRNA Promotes Gefitinib Resistance in Non-small Cell Lung Cancer

Zhou, S.·Wang, Y.·Wei, J.·An, K.·Shi, Y.·Zhang, X.·Wang, H.·Feng, L.·He, L.·Zhang, Y.·Ren, T.·Li, O.·Yang, Y.-G.·Kan, Q.·Tian, X.

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Abstract

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have produced durable complete responses, but the eventual development of acquired resistance presents a huge challenge in the treatment of non-small cell lung cancer (NSCLC). N7-methylguanosine (m7G), a prevalent post-transcriptional modification within RNA, play regulatory roles in RNA stability, expression dynamics, and functional diversity. Despite these insights, the contribution of m7G methylation to EGFR-TKIs resistance remains poorly characterized. Here, we identified substantial upregulation of mRNA internal m7G modifications and their associated methyltransferase complex composed of methyltransferase-like 1 (METTL1) /WD repeat domain 4 (WDR4) were significantly elevated in NSCLC specimens, correlating with therapeutic resistance. Functional assays confirmed that METTL1/WDR4 enhances gefitinib resistance in both cellular and animal models via the internal RNA m7G methyltransferase activity in NSCLC. Mechanistically, m7G MeRIP-seq coupled with RNA-seq identified sodium channel and clathrin linker 1 (SCLT1) as the m7G target of METTL1/WDR4. METTL1/WDR4 knockdown may result in a decrease in both the demethylation level and mRNA stability of the SCLT1 transcript, while overexpression of wild-type METTL1, but not its catalytically inactive mutant, rescues mRNA stability. METTL1/WDR4-mediated m7G modification of SCLT1 regulates gefitinib resistance by activating the NF-{kappa}B signaling. These results establish aberrant mRNA internal m7G modification as a novel resistance mechanism and propose therapeutic targeting of the METTL1/WDR4-SCLT1-NF-{kappa}B axis cascade to overcome EGFR-TKIs resistance.

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Zhou, S., Wang, Y., Wei, J., An, K., Shi, Y., Zhang, X., Wang, H., Feng, L., He, L., Zhang, Y., Ren, T., Li, O., Yang, Y.-G., Kan, Q., Tian, X.. 2025-03-27. METTL1/WDR4-mediated m7G Hypermethylation of SCLT1 mRNA Promotes Gefitinib Resistance in Non-small Cell Lung Cancer. https://doi.org/10.1101/2025.03.26.645570

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