Role of N7-methylguanosine in gastrointestinal tumors: Molecular mechanisms and therapeutic targets.

N7-methylguanosine (mG), a widely prevalent post-transcriptional modification of RNA, exhibits significant regulatory changes across diverse RNA molecules, thereby affecting essential RNA metabolic processes. Aberrant levels of mG modification have been increasingly linked to a broad spectrum of diseases, influencing oncogene expression and contributing to pathological mechanisms. The relationship between mG modification and the initiation and progression of various tumor types is intricate and multifaceted. Moreover, current evidence suggests that mG may play a role in regulating processes within immune cells, thereby implicating it in immune-related pathologies, including cancer. The targeted manipulation of mG and its regulatory pathways holds significant promise for advancements in immunotherapy, potentially enhancing the modulation of immune responses and overcoming drug resistance. In gastrointestinal (GI) tumors, where immune evasion and therapy resistance are prominent challenges, understanding the role of mG becomes particularly critical. This comprehensive review systematically examines the current body of research on mG within the context of GI tumors, offering a detailed analysis of its dysregulated patterns in both malignant and immune cells. The molecular mechanisms underlying tumorigenesis mediated by mG epigenetics are summarized, and therapeutic strategies aiming at targeting mG modifications are discussed. Additionally, this review provides insights into potential future directions in the fields of diagnosis and prognosis.