MicroRNAs in oral squamous cell carcinoma progression

Oral squamous cell carcinoma (OSCC) represents almost 90% of all oral cancers and remains a highly morbidity- and mortality-associated disease because of the late diagnosis and the lack of reliable prognostic factors. MicroRNAs (miRNAs), small non-coding RNAs that regulate gene expression post-transcriptionally, have been recognized as promising diagnostic and prognostic biomarkers because of their stability in tissues and body fluids. This review aims to compile the existing evidence on the most important miRNAs involved in OSCC, including miR-155-5p, miR-1246, miR-24, miR-200, miR-34, miR-21, and miR-31, focusing on their expression levels, molecular targets, and clinical significance. Aberrant miRNAs affect pivotal oncogenic pathways like PI3K/Akt, Wnt/β-catenin, epithelial-mesenchymal transition, p53 pathway, and hypoxia-inducible factor signaling, contributing to the progression of tumors and resistance to treatments. The clinical utility of miRNAs in early diagnosis, prognosis, prediction of treatment response, and monitoring of the disease is also discussed, as well as the existing challenges and future directions. The combination of multi-miRNA signatures with cutting-edge computational tools may provide a new avenue for the implementation of precision oncology in OSCC management.