N7-Methylguanosine(m7G)modification occurs at the 5'cap of eukaryotic mRNA,as well as specific sites on tRNA and rRNA,and is widely present across various aspects of life.Aberrant m7Gmodification is involved in the dysregulation of gene expression and serves as a biomarker for multiple cancers,holding significant potential for applications in tumor diagnosis and therapy.This review summarizes the biological functions and regulatory mechanisms of m7G modification,as well as its potential clinical applications.It highlights the oncogenic roles of aberrant m7Gmodification and its association with prognosis,with a detailed discussion of the role and molecular mechanisms of abnormal m7G modification in regulating drug resistance in various cancers.