Cao Gao, Jiajia He, Jiemin Zhao, Xuefeng Ni, Yanjie Xu
{"title":"n6 -甲基腺苷修饰MEF2A通过PD-L1/SOX12轴减弱西妥昔单抗在结直肠癌中的敏感性。","authors":"Cao Gao, Jiajia He, Jiemin Zhao, Xuefeng Ni, Yanjie Xu","doi":"10.1038/s41420-025-02577-8","DOIUrl":null,"url":null,"abstract":"<p><p>Colorectal cancer (CRC) treatment is still a challenge due to chemoresistance. We explored MEF2A function and underlying mechanism on cetuximab sensitivity in CRC. In this study, cancer tissues and adjacent non-cancerous samples were harvested from CRC patients. Cell viability, proliferation and apoptosis in CRC cells were tested by CCK-8, EdU, colony formation, and flow cytometry assays. The binding of MEF2A on the PD-L1 promoter was validated using luciferase reporter assay, CHIP, and EMSA, while the relationship of PD-L1 and SOX12 mRNA, as well as RBM15/IGF2BP1 and MEF2A mRNA, was verified by RIP, RNA pull-down, or FISH combined with immunofluorescence. m6A modification level of MEF2A mRNA was assayed by MeRIP. The expressions of key genes and proteins, including MEF2A, PD-L1, SOX12, RBM15, IGF2BP1, apoptosis- and cell cycle-related proteins, were determined with RT-qPCR, western blot, or immunohistochemistry. In vivo function of MEF2A was validated by establishing a xenograft nude mice model. The results showed that MEF2A was increased in CRC cells and tissues, while it was higher in cetuximab-resistant CRC tissues. Silencing MEF2A improved the sensitivity of cetuximab in CRC cells and xenograft mice. MEF2A binds to PD-L1 promoter to transcriptionally upregulate PD-L1 expression. Increased cetuximab sensitivity was observed in PD-L1 knockout (KO) CRC cells. PD-L1 overexpression reversed the enhanced cetuximab sensitivity induced by MEF2A knockdown. PD-L1 binds to SOX12 mRNA to stabilize its expression. PD-L1 knockdown augmented cetuximab sensitivity, which was overturned by SOX12 overexpression. The m6A modification mediated by RBM15/IGF2BP1 upregulated MEF2A expression in cetuximab-resistant CRC tissues. In conclusion, m6A-modified MEF2A alleviated cetuximab sensitivity in CRC via PD-L1/SOX12 mRNA axis, indicating that MEF2A might function as a promising therapeutic target against cetuximab-resistant CRC.</p>","PeriodicalId":9735,"journal":{"name":"Cell Death Discovery","volume":"11 1","pages":"294"},"PeriodicalIF":7.0000,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12219012/pdf/","citationCount":"0","resultStr":"{\"title\":\"N6-methyladenosine modification of MEF2A weakens cetuximab sensitivity in colorectal cancer via PD-L1/SOX12 axis.\",\"authors\":\"Cao Gao, Jiajia He, Jiemin Zhao, Xuefeng Ni, Yanjie Xu\",\"doi\":\"10.1038/s41420-025-02577-8\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Colorectal cancer (CRC) treatment is still a challenge due to chemoresistance. We explored MEF2A function and underlying mechanism on cetuximab sensitivity in CRC. In this study, cancer tissues and adjacent non-cancerous samples were harvested from CRC patients. Cell viability, proliferation and apoptosis in CRC cells were tested by CCK-8, EdU, colony formation, and flow cytometry assays. The binding of MEF2A on the PD-L1 promoter was validated using luciferase reporter assay, CHIP, and EMSA, while the relationship of PD-L1 and SOX12 mRNA, as well as RBM15/IGF2BP1 and MEF2A mRNA, was verified by RIP, RNA pull-down, or FISH combined with immunofluorescence. m6A modification level of MEF2A mRNA was assayed by MeRIP. The expressions of key genes and proteins, including MEF2A, PD-L1, SOX12, RBM15, IGF2BP1, apoptosis- and cell cycle-related proteins, were determined with RT-qPCR, western blot, or immunohistochemistry. In vivo function of MEF2A was validated by establishing a xenograft nude mice model. The results showed that MEF2A was increased in CRC cells and tissues, while it was higher in cetuximab-resistant CRC tissues. Silencing MEF2A improved the sensitivity of cetuximab in CRC cells and xenograft mice. MEF2A binds to PD-L1 promoter to transcriptionally upregulate PD-L1 expression. Increased cetuximab sensitivity was observed in PD-L1 knockout (KO) CRC cells. PD-L1 overexpression reversed the enhanced cetuximab sensitivity induced by MEF2A knockdown. PD-L1 binds to SOX12 mRNA to stabilize its expression. PD-L1 knockdown augmented cetuximab sensitivity, which was overturned by SOX12 overexpression. The m6A modification mediated by RBM15/IGF2BP1 upregulated MEF2A expression in cetuximab-resistant CRC tissues. In conclusion, m6A-modified MEF2A alleviated cetuximab sensitivity in CRC via PD-L1/SOX12 mRNA axis, indicating that MEF2A might function as a promising therapeutic target against cetuximab-resistant CRC.</p>\",\"PeriodicalId\":9735,\"journal\":{\"name\":\"Cell Death Discovery\",\"volume\":\"11 1\",\"pages\":\"294\"},\"PeriodicalIF\":7.0000,\"publicationDate\":\"2025-07-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12219012/pdf/\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Cell Death Discovery\",\"FirstCategoryId\":\"3\",\"ListUrlMain\":\"https://doi.org/10.1038/s41420-025-02577-8\",\"RegionNum\":2,\"RegionCategory\":\"生物学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CELL BIOLOGY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cell Death Discovery","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1038/s41420-025-02577-8","RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CELL BIOLOGY","Score":null,"Total":0}
N6-methyladenosine modification of MEF2A weakens cetuximab sensitivity in colorectal cancer via PD-L1/SOX12 axis.
Colorectal cancer (CRC) treatment is still a challenge due to chemoresistance. We explored MEF2A function and underlying mechanism on cetuximab sensitivity in CRC. In this study, cancer tissues and adjacent non-cancerous samples were harvested from CRC patients. Cell viability, proliferation and apoptosis in CRC cells were tested by CCK-8, EdU, colony formation, and flow cytometry assays. The binding of MEF2A on the PD-L1 promoter was validated using luciferase reporter assay, CHIP, and EMSA, while the relationship of PD-L1 and SOX12 mRNA, as well as RBM15/IGF2BP1 and MEF2A mRNA, was verified by RIP, RNA pull-down, or FISH combined with immunofluorescence. m6A modification level of MEF2A mRNA was assayed by MeRIP. The expressions of key genes and proteins, including MEF2A, PD-L1, SOX12, RBM15, IGF2BP1, apoptosis- and cell cycle-related proteins, were determined with RT-qPCR, western blot, or immunohistochemistry. In vivo function of MEF2A was validated by establishing a xenograft nude mice model. The results showed that MEF2A was increased in CRC cells and tissues, while it was higher in cetuximab-resistant CRC tissues. Silencing MEF2A improved the sensitivity of cetuximab in CRC cells and xenograft mice. MEF2A binds to PD-L1 promoter to transcriptionally upregulate PD-L1 expression. Increased cetuximab sensitivity was observed in PD-L1 knockout (KO) CRC cells. PD-L1 overexpression reversed the enhanced cetuximab sensitivity induced by MEF2A knockdown. PD-L1 binds to SOX12 mRNA to stabilize its expression. PD-L1 knockdown augmented cetuximab sensitivity, which was overturned by SOX12 overexpression. The m6A modification mediated by RBM15/IGF2BP1 upregulated MEF2A expression in cetuximab-resistant CRC tissues. In conclusion, m6A-modified MEF2A alleviated cetuximab sensitivity in CRC via PD-L1/SOX12 mRNA axis, indicating that MEF2A might function as a promising therapeutic target against cetuximab-resistant CRC.
期刊介绍:
Cell Death Discovery is a multidisciplinary, international, online-only, open access journal, dedicated to publishing research at the intersection of medicine with biochemistry, pharmacology, immunology, cell biology and cell death, provided it is scientifically sound. The unrestricted access to research findings in Cell Death Discovery will foster a dynamic and highly productive dialogue between basic scientists and clinicians, as well as researchers in industry with a focus on cancer, neurobiology and inflammation research. As an official journal of the Cell Death Differentiation Association (ADMC), Cell Death Discovery will build upon the success of Cell Death & Differentiation and Cell Death & Disease in publishing important peer-reviewed original research, timely reviews and editorial commentary.
Cell Death Discovery is committed to increasing the reproducibility of research. To this end, in conjunction with its sister journals Cell Death & Differentiation and Cell Death & Disease, Cell Death Discovery provides a unique forum for scientists as well as clinicians and members of the pharmaceutical and biotechnical industry. It is committed to the rapid publication of high quality original papers that relate to these subjects, together with topical, usually solicited, reviews, editorial correspondence and occasional commentaries on controversial and scientifically informative issues.