5-Methylcytosine in non-communicable and communicable diseases

Abstract

5-Methylcytosine (m₅C) has attracted increasing attention as an important epitranscriptomic modification that regulates RNA metabolism and diverse cellular processes. It is dynamically controlled by writer, eraser, and reader proteins that govern the life cycle of the methylated transcript. Studies have demonstrated that aberrant m₅C enzymatic dysregulation is linked to a wide range of human diseases, ranging from non-communicable diseases like cancer to communicable diseases like viral infections. Notably, m₅C regulatory enzymes may exert context-dependent dual roles, functioning either protectively or pathogenically within and across different disease settings. However, current research efforts remain largely confined to individual disease models, and a unified understanding of m₅C functions across pathologies remains lacking. Furthermore, clinical translation targeting m₅C modification remains limited, with most findings restricted to experimental studies. This review aims to provide a comprehensive overview of current knowledge on m₅C-mediated mechanisms across both communicable and non-communicable contexts and evaluate their potential as therapeutic targets.

Keywords

Epitranscriptomic / 5-Methylcytosine (m ₅C) / Cancer / Cardiovascular diseases / Chronic respiratory diseases / Virus infection

References

[1] Crick F. Central dogma of molecular biology. Nature 1970; 227(5258): 561-563. doi: 10.1038/227561a0.

[2] Boccaletto P, Stefaniak F, Ray A, Cappannini A, Mukherjee S, Purta E, et al. MODOMICS: A database of RNA modification pathways. 2021 update. Nucleic Acids Res 2022; 50(D1): D231-D235. doi: 10.1093/nar/gkab1083.

[3] Xiang Y, Laurent B, Hsu CH, Nachtergaele S, Lu Z, Sheng W, et al. RNA m₆A methylation regulates the ultraviolet-induced DNA damage response . Nature 2017; 543(7646): 573-576. doi: 10.1038/nature21671.

[4] Yang X, Yang Y, Sun BF, Chen YS, Xu JW, Lai WY, et al. 5-methylcytosine promotes mRNA export-NSUN2 as the methyltransferase and ALYREF as an m⁵C reader . Cell Res 2017; 27(5): 606-625. doi: 10.1038/cr.2017.55.

[5] Squires JE, Patel HR, Nousch M, Sibbritt T, Humphreys DT, Parker BJ, et al. Widespread occurrence of 5-methylcytosine in human coding and non-coding RNA. Nucleic Acids Res 2012; 40(11): 5023-5033. doi: 10.1093/nar/gks144.

[6] Chen X, Li A, Sun BF, Yang Y, Han YN, Yuan X, et al. 5-methylcytosine promotes pathogenesis of bladder cancer through stabilizing mRNAs. Nat Cell Biol 2019; 21(8): 978-990. doi: 10.1038/s41556-019-0361-y.

[7] Riquelme-Barrios S, Cusack SA, Rivera-Montero L, Vásquez-Camus L, Burdack K, Brameyer S, et al. Epitranscriptomic control of stress adaptations in Escherichia coli. Nucleic Acids Res 2026; 54(3). doi: 10.1093/nar/gkag042.

[8] Sun Z, Xue S, Zhang M, Xu H, Hu X, Chen S, et al. Aberrant NSUN2-mediated m₅C modification of H19 lncRNA is associated with poor differentiation of hepatocellular carcinoma. Oncogene 2020; 39(45): 6906-6919. doi: 10.1038/s41388-020-01475-w.

[9] Van Haute L, Dietmann S, Kremer L, Hussain S, Pearce SF, Powell CA, et al. Deficient methylation and formylation of mt-tRNAmet wobble cytosine in a patient carrying mutations in NSUN3. Nat Commun 2016; 7(1). doi: 10.1038/ncomms12039.

[10] Liu Y, Wu F, Liu K, Yu S, Wang C, Li X, et al. NSUN2 promotes cardiac hypertrophy by activating LARP1-GATA4 axis. Engineering 2025. doi: 10.1016/j.eng.2025.05.016.

[11] Ding S, Liu H, Liu L, Ma L, Chen Z, Zhu M, et al. Epigenetic addition of m₅C to HBV transcripts promotes viral replication and evasion of innate antiviral responses . Cell Death Dis 2024; 15(1): 39. doi: 10.1038/s41419-023-06412-9.

[12] Liu M, Guo G, Qian P, Mu J, Lu B, He X, et al. 5-methylcytosine modification by Plasmodium NSUN2 stabilizes mRNA and mediates the development of gametocytes. Proc Natl Acad Sci USA 2022; 119(9). doi: 10.1073/pnas.2110713119.

[13] Tang R, Chen X, Shang X, Hu Y, Lu B, Du X, et al. m₅C methylation of mitochondrial RNA and non-coding RNA by NSUN3 is associated with variant gene expression and asexual blood-stage development in Plasmodium falciparum . Parasit Vectors 2025; 18(1): 121. doi: 10.1186/s13071-025-06746-7.

[14] Cantara WA, Crain PF, Rozenski J, McCloskey JA, Harris KA, Zhang X, et al. The RNA modification database, RNAMDB: 2011 update. Nucleic Acids Res 2010; 39(suppl_1): D195-D201. doi: 10.1093/nar/gkq1028.

[15] Hotchkiss RD. The quantitative separation of purines, pyrimidines, and nucleosides by paper chromatography. J Biol Chem 1948; 175(1): 315-332. doi: 10.1016/S0021-9258(18)57261-6.

[16] Desrosiers R, Friderici K, Rottman F. Identification of methylated nucleosides in messenger RNA from novikoff hepatoma cells. Proc Natl Acad Sci USA 1974; 71(10): 3971-3975. doi: 10.1073/pnas.71.10.3971.

[17] Schapira M. Structural chemistry of human RNA methyltransferases. ACS Chem Biol 2016; 11(3): 575-582. doi: 10.1021/acschembio.5b00781.

[18] Chen YS, Yang WL, Zhao YL, Yang YG. Dynamic transcriptomic m₅C and its regulatory role in RNA processing . Wiley Interdiscip Rev RNA 2021; 12(4): e1639. doi: 10.1002/wrna.1639.

[19] Liao H, Gaur A, McConie H, Shekar A, Wang K, Chang JT, et al. Human NOP2/NSUN1 regulates ribosome biogenesis through non-catalytic complex formation with box c/d snornps. Nucleic Acids Res 2022; 50(18): 10695-10716. doi: 10.1093/nar/gkac817.

[20] Fu L, Guerrero CR, Zhong N, Amato NJ, Liu Y, Liu S, et al. Tet-mediated formation of 5-hydroxymethylcytosine in RNA. J Am Chem Soc 2014; 136(33): 11582-11585. doi: 10.1021/ja505305z.

[21] Meng H, Miao H, Zhang Y, Chen T, Yuan L, Wan Y, et al. YBX1 promotes homologous recombination and resistance to platinum-induced stress in ovarian cancer by recognizing m⁵C modification . Cancer Lett 2024; 597. doi: 10.1016/j.canlet.2024.217064.

[22] Zhong L, Wu J, Zhou B, Kang J, Wang X, Ye F, et al. ALYREF recruits ELAVL1 to promote colorectal tumorigenesis via facilitating RNA m₅C recognition and nuclear export . NPJ Precis Oncol 2024; 8(1): 243. doi: 10.1038/s41698-024-00737-0.

[23] Guo J, Zou Z, Dou X, Zhao X, Wang Y, Wei L, et al. Zebrafish Mbd5 binds to RNA m₅C and regulates histone deubiquitylation and gene expression in development metabolism and behavior . Nucleic Acids Res 2024; 52(8): 4257-4275. doi: 10.1093/nar/gkae093.

[24] Zou Z, Dou X, Li Y, Zhang Z, Wang J, Gao B, et al. RNA m₅C oxidation by TET2 regulates chromatin state and leukaemogenesis . Nature 2024; 634(8035): 986-994. doi: 10.1038/s41586-024-07969-x.

[25] World Health Organization: WHO. Noncommunicable diseases. 2025. [Online] Available from: https://www.who.int/news-room/fact-sheets/detail/noncommunicable-diseases [Accessed on 23 Mar 2026].

[26] Cheng JX, Wood S, Tang D, Degenstein L, Joachimiak A, Stevens R. Overcoming venetoclax resistance in leukemia with AI-designed RNA epigenetic inhibitors. Blood 2023; 142. doi: 10.1182/blood-2023-178258.

[27] Li S, Liu Y, Wu X, Pan M, Zhao H, Hong Y, et al. The m₅C methyltransferase NSUN2 promotes progression of acute myeloid leukemia by regulating serine metabolism . Cell Rep 2025; 44(5). doi: 10.1016/j.celrep.2025.115661.

[28] Li Y, Xue M, Deng X, Dong L, Nguyen LXT, Ren L, et al. TET2-mediated mRNA demethylation regulates leukemia stem cell homing and self-renewal. Cell Stem Cell 2023; 30(8): 1072-1090. doi: 10.1016/j.stem.2023.07.001.

[29] Qi Q, Zhong R, Huang Y, Tang Y, Zhang XW, Liu C, et al. The RNA m₅C methyltransferase NSUN2 promotes progression of hepatocellular carcinoma by enhancing PKM2-mediated glycolysis . Cell Death Dis 2025; 16(1): 82. doi: 10.1038/s41419-025-07414-5.

[30] Song D, An K, Zhai W, Feng L, Xu Y, Sun R, et al. NSUN2-mediated mRNA m₅C modification regulates the progression of hepatocellular carcinoma. GPB 2023; 21(4): 823-833. doi: 10.1016/j.gpb.2022.09.007.

[31] Zhang XW, Wu LY, Liu HR, Huang Y, Qi Q, Zhong R, et al. NSUN5 promotes progression and predicts poor prognosis in hepatocellular carcinoma. Oncol Lett 2022; 24(6): 439. doi: 10.3892/ol.2022.13559.

[32] Ortiz-Barahona V, Soler M, Davalos V, García-Prieto CA, Janin M, Setien F, et al. Epigenetic inactivation of the 5-methylcytosine RNA methyltransferase NSUN7 is associated with clinical outcome and therapeutic vulnerability in liver cancer. Mol Cancer 2023; 22(1): 83. doi: 10.1186/s12943-023-01785-z.

[33] Sun GF, Ding H. NOP2-mediated m₅C methylation of XPD is associated with hepatocellular carcinoma progression . Neoplasma 2023; 70(3). doi: 10.4149/neo_2023_230110N17.

[34] Wang Y, Wei J, Feng L, Li O, Huang L, Zhou S, et al. Aberrant m₅C hypermethylation mediates intrinsic resistance to gefitinib through NSUN2/YBX1/QSOX1 axis in EGFR-mutant non-small-cell lung cancer . Mol Cancer 2023; 22(1): 81. doi: 10.1186/s12943-023-01780-4.

[35] Jiang Y, Zhu P, Liu Z, Zhou Y. USP8 deubiquitylation-boosted NSUN4 potentiates lung squamous cell carcinoma progression by m⁵C methylation of DHCR24 . Cell Rep 2025; 44(8). doi: 10.1016/j.celrep.2025.116158.

[36] Lu Z, Liu B, Kong D, Zhou X, Pei D, Liu D. NSUN6 regulates NM23-H1 expression in an m₅C manner to affect epithelial-mesenchymal transition in lung cancer . Med Princ Pract 2024; 33(1): 56-65. doi: 10.1159/000535479.

[37] Tong R, Li Y, Wang J, Liu C, Liu Y, Li R, et al. NSUN2 knockdown promotes the ferroptosis of colorectal cancer cells via m₅C modification of SLC7A11 mRNA . Biochem Genet 2026; 64(1): 524-537. doi: 10.1007/s10528-025-11035-0.

[38] Yang L, Shi J, Zhong M, Sun P, Zhang X, Lian Z, et al. NXPH4 mediated by m₅C contributes to the malignant characteristics of colorectal cancer via inhibiting HIF1A degradation . Cell Mol Biol Lett 2024; 29(1): 111. doi: 10.1186/s11658-024-00630-5.

[39] Jiang Z, Li S, Han MJ, Hu GM, Cheng P. High expression of NSUN5 promotes cell proliferation via cell cycle regulation in colorectal cancer. Am J Transl Res 2020; 12(7): 3858-3870.

[40] Zhao L, Xie R, Li L, Lu X, Wang L, Wang H, et al. CASC19 stabilization by ALYREF via m₅C modification and its impact on SCD in colorectal cancer cell aggressiveness and stemness . Cell Biosci 2026; 16: 40. doi: 10.1186/s13578-026-01539-6.

[41] Mei L, Shen C, Miao R, Wang JZ, Cao MD, Zhang YS, et al. RNA methyltransferase NSUN2 promotes gastric cancer cell proliferation by repressing p57kip2 by an m⁵C-dependent manner. Cell Death Dis 2020; 11(4): 270. doi: 10.1038/s41419-020-2487-z.

[42] Wang N, Chen RX, Deng MH, Wei WS, Zhou ZH, Ning K, et al. m₅C-dependent cross-regulation between nuclear reader ALYREF and writer NSUN2 promotes urothelial bladder cancer malignancy through facilitating RABL6/TK1 mRNAs splicing and stabilization . Cell Death Dis 2023; 14(2): 139. doi: 10.1038/s41419-023-05661-y.

[43] Zhang X, An K, Ge X, Sun Y, Wei J, Ren W, et al. NSUN2/YBX1 promotes the progression of breast cancer by enhancing HGH1 mRNA stability through m⁵C methylation . Breast Cancer Res 2024; 26(1): 94. doi: 10.1186/s13058-024-01847-0.

[44] Liu X, Wei Q, Yang C, Zhao H, Xu J, Mobet Y, et al. RNA m₅C modification upregulates E2F1 expression in a manner dependent on YBX1 phase separation and promotes tumor progression in ovarian cancer . Exp Mol Med 2024; 56(3): 600-615. doi: 10.1038/s12276-024-01184-4.

[45] Janin M, Ortiz-Barahona V, de Moura MC, Martínez-Cardús A, Llinàs-Arias P, Soler M, et al. Epigenetic loss of RNA-methyltransferase NSUN5 in glioma targets ribosomes to drive a stress adaptive translational program. Acta Neuropathol 2019; 138(6): 1053-1074. doi: 10.1007/s00401-019-02062-4.

[46] Yang R, Liang X, Wang H, Guo M, Shen H, Shi Y, et al. The RNA methyltransferase NSUN6 suppresses pancreatic cancer development by regulating cell proliferation. EBioMedicine 2021; 63. doi: 10.1016/j.ebiom.2020.103195.

[47] Liu Z, Feng R, Xu Y, Liu M, Wang H, Lu Y, et al. Identification of m₅C RNA modification-related gene signature for predicting prognosis and immune microenvironment-related characteristics of heart failure . Hereditas 2025; 162(1): 83. doi: 10.1186/s41065-025-00454-z.

[48] Huang Z, Pan J, Wang H, Du X, Xu Y, Wang Z, et al. Prognostic significance and tumor immune microenvironment heterogenicity of m₅C RNA methylation regulators in triple-negative breast cancer . Front Cell Dev Biol 2021; 9. doi: 10.3389/fcell.2021.657547.

[49] Geng Q, Wei Q, Shen Z, Zheng Y, Wang L, Xue W, et al. Comprehensive analysis of the prognostic value and immune infiltrates of the three-m₅C signature in colon carcinoma . Cancer Manag Res 2021; 13: 7989-8002. doi: 10.2147/CMAR.S331549.

[50] Chen B, Deng Y, Hong Y, Fan L, Zhai X, Hu H, et al. Metabolic recoding of NSUN2‐mediated m₅C modification promotes the progression of colorectal cancer via the NSUN2/YBX1/m₅C‐ENO1 positive feedback loop . Adv Sci 2024; 11(28). doi: 10.1002/advs.202309840.

[51] Chen T, Xu ZG, Luo J, Manne RK, Wang Z, Hsu CC, et al. NSUN2 is a glucose sensor suppressing cGAS/STING to maintain tumorigenesis and immunotherapy resistance. Cell Metab 2023; 35(10): 1782-1798. doi: 10.1016/j.cmet.2023.07.009.

[52] Chen B, Hong Y, Zhai X, Deng Y, Hu H, Tian S, et al. m₆A and m₅C modification of GPX4 facilitates anticancer immunity via STING activation . Cell Death Dis 2023; 14(12): 809. doi: 10.1038/s41419-023-06241-w.

[53] Li F, Liu T, Dong Y, Gao Q, Lu R, Deng Z. 5-methylcytosine RNA modification and its roles in cancer and cancer chemotherapy resistance. J Transl Med 2025; 23(1): 390. doi: 10.1186/s12967-025-06217-8.

[54] Hou X, Dong Q, Hao J, Liu M, Ning J, Tao M, et al. NSUN2-mediated m₅C modification drives alternative splicing reprogramming and promotes multidrug resistance in anaplastic thyroid cancer through the NSUN2/SRSF6/UAP1 signaling axis . Theranostics 2025; 15(7): 2757-2777. doi: 10.7150/thno.104713.

[55] Shao D, Liu C, Wang Y, Lin J, Cheng X, Han P, et al. DNMT1 determines osteosarcoma cell resistance to apoptosis by associatively modulating DNA and mRNA cytosine‐5 methylation. FASEB J 2023; 37(12). doi: 10.1096/fj.202301306R.

[56] Al-Ajlouni YA, Al Ta’ani O, Shamaileh G, Nagi Y, Tanashat M, Al-Bitar F, et al. The burden of cardiovascular diseases in Jordan: A longitudinal analysis from the global burden of disease study, 1990-2019. BMC Public Health 2024; 24(1): 879. doi: 10.1186/s12889-024-18316-0.

[57] Murakami Y, Wei FY, Kawamura Y, Horiguchi H, Kadomatsu T, Miyata K, et al. NSUN3-mediated mitochondrial tRNA 5-formylcytidine modification is essential for embryonic development and respiratory complexes in mice. Commun Biol 2023; 6(1): 307. doi: 10.1038/s42003-023-04680-x.

[58] Ghanbarian H, Wagner N, Polo B, Baudouy D, Kiani J, Michiels JF, et al. Dnmt2/Trdmt1 as mediator of RNA polymerase II transcriptional activity in cardiac growth. PLoS One 2016; 11(6). doi: 10.1371/journal.pone.0156953.

[59] Wang Y, Zan Y, Huang Y, Peng X, Ma S, Ren J, et al. NSUN2 alleviates doxorubicin-induced myocardial injury through Nrf2-mediated antioxidant stress. Cell Death Discov 2023; 9(1): 43. doi: 10.1038/s41420-022-01294-w.

[60] BoRanyi B, Lv X, Xiao D. NSUN2 inhibits NCOA4 expression to alleviate ferroptosis and inflammation in sepsis-induced myocardial injury in a m⁵C manner. J Cardiothorac Surg 2025; 20(1): 315. doi: 10.1186/s13019-025-03554-z.

[61] Hao Y, Li B, Tian W, Yin F, Liu W. The m₅C reader ALYREF regulates cardiac remodeling post-myocardial infarction by modulating extracellular matrix protein synthesis in cardiac fibroblasts . Biochim Biophys Acta Mol Cell Res 2025; 1872(7). doi: 10.1016/j.bbamcr.2025.120011.

[62] Hua J, Yu L, Xiong W, Ying R, Duan Q, Zhu J, et al. ALYREF inhibits ferroptosis in vascular endothelial cells and improves atherosclerosis by epigenetic modification of CISD1. Clin Epigenetics 2025; 17(1): 151. doi: 10.1186/s13148-025-01955-4.

[63] Luo Y, Feng J, Xu Q, Wang W, Wang X. NSUN2 deficiency protects endothelium from inflammation via mRNA methylation of ICAM-1. Circ Res 2016; 118(6): 944-956. doi: 10.1161/circresaha.115.307674.

[64] Zhao H, Kong Y, Ding P, Yang L, Li N. The role of 5-methylcytosine regulator-related genes in diagnostic and immune regulatory functions in atherosclerosis. Front Immunol 2025; 16. doi: 10.3389/fimmu.2025.1636323.

[65] Liu JC, Wang WJ, Zhang TT, Yang QC, Dilimulati H, An ST. TET3‐mediated m₅C modification of CCAT2 accelerates cardiac microvascular endothelial cell damage in acute coronary syndrome . Kaohsiung J Med Sci 2025; 42(5). doi: 10.1002/kjm2.70128.

[66] Pisano A, Cerbelli B, Perli E, Pelullo M, Bargelli V, Preziuso C, et al. Impaired mitochondrial biogenesis is a common feature to myocardial hypertrophy and end-stage ischemic heart failure. Cardiovasc Pathol 2016; 25(2): 103-112. doi: 10.1016/j.carpath.2015.09.009.

[67] Metodiev MD, Spåhr H, Loguercio Polosa P, Meharg C, Becker C, Altmueller J, et al. NSUN4 is a dual function mitochondrial protein required for both methylation of 12S rRNA and coordination of mitoribosomal assembly. PLoS Genet 2014; 10(2). doi: 10.1371/journal.pgen.1004110.

[68] Sun Z, Li N, Huang M, Li Y, Wang C, Qu Z, et al. Myofibroblast specific knockdown of NSUN2 suppresses cardiac fibrosis post-myocardial infarction. J Mol Cell Cardiol 2025; 209: 27-36. doi: 10.1016/j.yjmcc.2025.09.009.

[69] Varma E, Burghaus J, Schwarzl T, Sekaran T, Gupta P, Górska AA, et al. Translational control of YBX1 expression regulates cardiac function in response to pressure overload in vivo. Basic Res Cardiol 2023; 118(1): 25. doi: 10.1007/s00395-023-00996-1.

[70] Zhai Y, Zhu C, Zhu T, Song W, Tang Y, Jiang L, et al. Global, regional, and national burden of chronic respiratory diseases, 1990-2021 and predictions to 2035: Analysis of data from the global burden of disease study 2021. Ann Med 2025; 57(1). doi: 10.1080/07853890.2025.2530225.

[71] Wu F, Zhao J. NSUN2 knockdown alleviates asthma progression by inhibiting Hnrnpk expression through decreased 5-methylcytosine. J Inflamm Res 2025; 18: 11401-11413. doi: 10.2147/JIR.S531754.

[72] Han X, Liu H, Zhang Z, Yang W, Wu C, Liu X, et al. Epitranscriptomic 5-methylcytosine profile in PM 2.5-induced mouse pulmonary fibrosis. Genom Proteom Bioinform 2020; 18(1): 41-51. doi: 10.1016/j.gpb.2019.11.005.

[73] Jiang X, Cheng X, Wan Q. NSUN2 knockdown ameliorates hepatic glucose and lipid metabolism disorders in type 2 diabetes mellitus through the inhibition of ACSL6 m⁵C methylation . Lipids Health Dis 2025; 24(1): 236. doi: 10.1186/s12944-025-02652-0.

[74] Wang R, Qu J, Chen M, Han T, Liu Z, Wang H. NSUN2 knockdown inhibits macrophage infiltration in diabetic nephropathy via reducing N₅-methylcytosine methylation of SOCS1 . Int Urol Nephrol 2025; 57(2): 643-653. doi: 10.1007/s11255-024-04214-2.

[75] Ma XH, Hu ZY, Wang YK, Ma Y, Liu GP, Liu XQ. TET 2 deficiency exacerbates podocyte injury and mitophagy disorder in diabetic nephropathy by regulating m⁵C methylation of BCA3 . FASEB J 2025; 39(19). doi: 10.1096/fj.202500946R.

[76] Wang R, Xue W, Kan F, Zhang H, Wang D, Wang L, et al. NSUN2 affects diabetic retinopathy progression by regulating MUC1 expression through RNA m⁵C methylation . J Transl Med 2024; 22(1): 476. doi: 10.1186/s12967-024-05287-4.

[77] Li H, Boulougoura A, Endo Y, Tsokos GC. Abnormalities of T cells in systemic lupus erythematosus: New insights in pathogenesis and therapeutic strategies. J Autoimmun 2022; 132. doi: 10.1016/j.jaut.2022.102870.

[78] Ren B, He K, Wei N, Liu S, Cui X, Yang X, et al. Nanoparticle‐delivered siRNA targeting NSUN4 relieves systemic lupus erythematosus through declining mitophagy‐mediated CD8⁺ T cell exhaustion . MedComm 2025; 6(8): e70311. doi: 10.1002/mco2.70311.

[79] Huang Y, Xu P, Liao F, Ca H, Wang X, Wang X, et al. Fat mass and obesity-associated protein inhibit the pathology of rheumatoid arthritis through the NSUN2/SFRP1/WNT/β-catenin signal axis. J Pharm Pharmacol 2024; 76(3): 283-294. doi: 10.1093/jpp/rgae003.

[80] He C, Zhang J, Deli G, Zhao K, Liu L, Lai B, et al. NSUN2 aggravates M1 macrophage polarization in arthritis progression through m₅C modification of CCL2 . Mol Immunol 2026; 190: 45-55. doi: 10.1016/j.molimm.2025.12.015.

[81] Shao M, Li C, Li J, Chen R, Wang Y, Su J, et al. NSUN2 promotes PM2.5-induced epithelial-mesenchymal transition through methylating chitinase 3-like-1 mRNA. J Hazard Mater 2025; 495. doi: 10.1016/j.jhazmat.2025.138883.

[82] Wu J, Li X, Kong D, Zheng X, Du W, Zhang Y, et al. Exploring the importance of m₅C in the diagnosis and subtype classification of COPD using the GEO database . Gene 2024; 895. doi: 10.1016/j.gene.2023.147987.

[83] Huang T, Zhou HF. A novel 5‐methylcytosine‐and immune‐related prognostic signature is a potential marker of idiopathic pulmonary fibrosis. Comput Math Methods Med 2022; 2022(1). doi: 10.1155/2022/1685384.

[84] Cerf ME. Beta cell dysfunction and insulin resistance. Front Endocrinol 2013; 4. doi: 10.3389/fendo.2013.00037.

[85] Song Y, Jiang Y, Shi L, He C, Zhang W, Xu Z, et al. Comprehensive analysis of key m⁵C modification-related genes in type 2 diabetes . Front Genet 2022; 13. doi: 10.3389/fgene.2022.1015879.

[86] Zhang D, Hua W, Sun F, Wen C, Cheong LY, Xie R, et al. The changes in global burden of autoimmune diseases two years after the Covid-19 pandemic: A trend analysis based on the global burden of disease study 2021. J Transl Autoimmun 2025; 10. doi: 10.1016/j.jtauto.2025.100289.

[87] Guo G, Wang H, Shi X, Ye L, Yan K, Chen Z, et al. Disease activity-associated alteration of mRNA m₅C methylation in CD4 + T cells of systemic lupus erythematosus . Front Cell Dev Biol 2020; 8. doi: 10.3389/fcell.2020.00430.

[88] Kong W, Biswas A, Zhou D, Fiches G, Fujinaga K, Santoso N, et al. Nucleolar protein NOP2/NSUN1 suppresses HIV-1 transcription and promotes viral latency by competing with Tat for TAR binding and methylation. PLoS Pathog 2020; 16(3). doi: 10.1371/journal.ppat.1008430.

[89] Courtney DG, Tsai K, Bogerd HP, Kennedy EM, Law BA, Emery A, et al. Epitranscriptomic addition of m₅C to HIV-1 transcripts regulates viral gene expression . Cell Host Microbe 2019; 26(2): 217-227. doi: 10.1016/j.chom.2019.07.005.

[90] Feng J, Xu T, He M, Li J, Yao P, Ma C, et al. NSUN2-mediated m₅C modification of HBV RNA positively regulates HBV replication . PLoS Pathog 2023; 19(12). doi: 10.1371/journal.ppat.1011808.

[91] Li ZL, Xie Y, Xie Y, Chen H, Zhou X, Liu M, et al. HCV 5-methylcytosine enhances viral RNA replication through interaction with m⁵C reader YBX1 . ACS Chem Biol 2024; 19(7): 1648-1660. doi: 10.1021/acschembio.4c00322.

[92] Eckwahl M, Xu R, Michalkiewicz J, Zhang W, Patel P, Cai Z, et al. 5-methylcytosine RNA modifications promote retrovirus replication in an ALYREF reader protein-dependent manner. J Virol 2020; 94(13). doi: 10.1128/jvi.00544-20.

[93] Wang H, Feng J, Fu Z, Xu T, Liu J, Yang S, et al. Epitranscriptomic m₅C methylation of SARS-CoV-2 RNA regulates viral replication and the virulence of progeny viruses in the new infection . Sci Adv 2024; 10(32). doi: 10.1126/sciadv.adn9519.

[94] Yang YP, Wang CH, Sun JR, Chien Y, Chien CS, Chiou GY, et al. Epitranscriptomic modulation of TET2 inhibition suppressed SARS-CoV-2 infection and blocked viral nucleocapsid protein in induced-pluripotent-stem-cell-derived cardiomyocyte screening models. Biomater Res 2025; 29. doi: 10.34133/bmr.0229.

[95] Hu J, Jiang S, You W, Hao R, Li J, Gong S, et al. NSUN2-dependent 5-methylcytosine modification regulates Influenza A virus gene expression and genomic packaging. bioRxiv [Preprint]. November 26, 2025. doi: 10.1101/2025.11.26.690652.

[96] Tang R, Fan Y, Lu B, Jiang Q, Cheng X, Zhang Z, et al. The RNA m₅C methyltransferase NSUN1 modulates human malaria gene expression during intraerythrocytic development . Front Cell Infect Microbiol 2024; 14. doi: 10.3389/fcimb.2024.1474229.

[97] Bezerra AM, Leite AB, de Souza Reis CR, de Lemos Padilha Pitta JL, Maran SR, Moretti NS, et al. Impact on the Leishmania mexicana transcriptome due to knockout of genes encoding orthologs of methyltransferases involved in m₁A and m₅C mRNA modifications . Parasit Vectors 2025; 18(1): 315. doi: 10.1186/s13071-025-06969-8.

[98] Estibariz I, Overmann A, Ailloud F, Krebes J, Josenhans C, Suerbaum S. The core genome m₅C methyltransferase JHP1050 (M.Hpy99III) plays an important role in orchestrating gene expression in Helicobacter pylori. Nucleic Acids Res 2019; 47(5): 2336-2348. doi: 10.1093/nar/gky1307.

[99] Abdullah MF, Yee KS, Zainal N, AbuBakar S, Ling CK. Role of the epitranscriptome in viral infections: Beneficial or detrimental? Mem Inst Oswaldo Cruz 2025; 120. doi: 10.1590/0074-02760250055.

[100] Hao H, Chen Z, Zhang F, Huang Y, Luo F, Zuo L, et al. NSUN2‑mediated epitranscriptomic and ubiquitin modulation of Nipah virus matrix protein reveals a dual-targeting antiviral strategy. Protein Cell 2026; 17(7): 644-661. doi: 10.1093/procel/pwag003.

[101] Dev RR, Ganji R, Singh SP, Mahalingam S, Banerjee S, Khosla S. Cytosine methylation by DNMT2 facilitates stability and survival of HIV-1 RNA in the host cell during infection. Biochem J 2017; 474(12): 2009-2026. doi: 10.1042/BCJ20170258.

[102] Bhattacharya T, Yan L, Crawford JM, Zaher H, Newton ILG, Hardy RW. Differential viral RNA methylation contributes to pathogen blocking in Wolbachia-colonized arthropods. PLoS Pathog 2022; 18(3). doi: 10.1371/journal.ppat.1010393.

[103] Zhang G, Hussain M, O’Neill SL, Asgari S. Wolbachia uses a host microRNA to regulate transcripts of a methyltransferase, contributing to dengue virus inhibition in Aedes aegypti. Proc Natl Acad Sci USA 2013; 110(25): 10276-10281. doi: 10.1073/pnas.1303603110.

[104] Henry BA, Kanarek JP, Kotter A, Helm M, Lee N. 5-methylcytosine modification of an Epstein-Barr virus noncoding RNA decreases its stability. RNA 2020; 26(8): 1038-1048. doi: 10.1261/rna.075275.120.

[105] Zhang Y, Zhang LS, Dai Q, Chen P, Lu M, Kairis EL, et al. 5-methylcytosine (m₅C) RNA modification controls the innate immune response to virus infection by regulating type I interferons . Proc Natl Acad Sci USA 2022; 119(42). doi: 10.1073/pnas.2123338119.

[106] Wang H, Feng J, Zeng C, Liu J, Fu Z, Wang D, et al. NSUN2-mediated m₅C methylation of IRF3 mRNA negatively regulates type I interferon responses during various viral infections . Emerg Microbes Infect 2023; 12(1). doi: 10.1080/22221751.2023.2178238.

[107] Belete D, Amare A, Andualem T, Kasew D, Biset S. Prevalence of intestinal parasitic infections and associated factors among presumptive pulmonary tuberculosis patients at Debre Tabor Referral hospital, South Gondar, northwest Ethiopia: A cross‐sectional study. J Parasitol Res 2024; 2024(1). doi: 10.1155/2024/8993666.

[108] Pisciotta A, Sampino AM, Presentato A, Galardini M, Manteca A, Alduina R. The DNA cytosine methylome revealed two methylation motifs in the upstream regions of genes related to morphological and physiological differentiation in Streptomyces coelicolor A(3)2 M145. Sci Rep 2023; 13(1): 7038. doi: 10.1038/s41598-023-34075-1.

[109] Gu XR, Gustafsson C, Ku J, Yu M, Santi DV. Identification of the 16S rRNA m⁵C967 methyltransferase from Escherichia coli . Biochemistry 1999; 38(13): 4053-4057. doi: 10.1021/bi982364y.

[110] Demirci H, Larsen LH, Hansen T, Rasmussen A, Cadambi A, Gregory ST, et al. Multi-site-specific 16s rRNA methyltransferase Rsmf from Thermus thermophilus. RNA 2010; 16(8): 1584-1596. doi: 10.1261/rna.2088310.

[111] Yin H, Huang Z, Niu S, Ming L, Jiang H, Gu L, et al. 5-methylcytosine (m₅C) modification in peripheral blood immune cells is a novel non-invasive biomarker for colorectal cancer diagnosis . Front Immunol 2022; 13. doi: 10.3389/fimmu.2022.967921.

[112] Huang M, Ming L, Jiang H, Jiang P, Jiang X, Yin H, et al. Diagnostic value of aberrant decreased 5-methylcytosine RNA modification in leukocytes for non-small cell lung cancer. J Cancer 2023; 14(12): 2198-2208. doi: 10.7150/jca.85681.

[113] STORM Therapeutics: Storm therapeutics presented interim phase 1 clinical data on its METTL3 RNA methyltransferase inhibitor STC-15 at ASCO 2024. STORM Therapeutics. [Online]. Available from: https://www.stormtherapeutics.com/news/press-releases/storm-therapeutics-presented-interim-phase-1-clinical-data-on-its-mettl3-rna-methyltransferase-inhibitor-stc-15-at-asco-2024/ [Accessed on 15 Apr 2026].

[114] Ye W, Zhao Y, Zhou Y, Huang J, He X, Ma Z, et al. NSUN2-mediated cytosine-5 methylation of FSP1 protects acute myeloid leukemia cells from ferroptosis. Mol Cancer 2025; 24(1): 201. doi: 10.1186/s12943-025-02394-8.

[115] Tang Z, Zhang N, Chen S, Fang J, Tang X, Lou Y, et al. Bipyridine derivatives as NOP2/sun RNA methyltransferase 3 inhibitors for the treatment of colorectal cancer. J Med Chem 2024; 67(15): 13446-13473. doi: 10.1021/acs.jmedchem.4c01323.

[116] Zhang T, Zhao F, Li J, Sun X, Zhang X, Wang H, et al. Programmable RNA 5-methylcytosine (m₅C) modification of cellular RNAs by dCasRx conjugated methyltransferase and demethylase . Nucleic Acids Res 2024; 52(6): 2776-2791. doi: 10.1093/nar/gkae110.