Role of RNA 5‑methylcytosine modification in cancer: Insights from coding and non‑coding RNAs (Review)

RNA modifications serve notable roles in various biological processes, with >170 identified modifications. These modifications increase the complexity of RNA species by influencing their tertiary structure, biogenesis, localization and function. The combination of high‑throughput detection technologies and corresponding analytical workflows provides a precise 5‑methylcytosine (m⁵C) landscape, helping to elucidate its biological functions. The m⁵C methylation occurs in coding and non‑coding RNAs and is dynamically regulated by related enzymes, including methyltransferases (writers), demethylases (erasers) and binding proteins (readers). m⁵C is involved in various physiological functions and regulates the progression of numerous types of tumors. Aberrant m⁵C RNA modifications contribute to the proliferation, migration and drug resistance of cancer cells, suggesting that targeting aberrant posttranscriptional modifications in cancer cells may hold promise as an efficient therapy for tumors. The present review systematically outlines the regulatory components of m⁵C modification, emphasizing their dynamic regulatory roles in RNA metabolism and function. The mechanisms by which m⁵C modification promotes tumor progression through the regulation of cancer cell proliferation, migration and drug resistance are summarized. The present review proposes that targeting abnormal m⁵C modifications could serve as a novel strategy for cancer treatment, offering new research directions in oncology.