Small RNAs and tooth development: The role of microRNAs in tooth agenesis and impaction

Background/purpose: Tooth development, or odontogenesis, is a complex process in which several molecular pathways play a key role. Recently, microRNAs, a class of approximately 20-nucleotide small RNA molecules that regulate gene expression, have been implicated in the odontogenesis process. This study aimed to assess the role of miRNAs in odontogenesis anomalies, specifically agenesis and impaction. Materials and methods: We analyzed a manually curated list of 82 miRNAs associated with human odontogenesis, sourced from literature data. Employing two different approaches to validate findings, we conducted functional enrichment analysis to evaluate the cell pathways, diseases, and phenotypes enriched for those miRNAs. Results: Our findings indicate that the analyzed miRNAs regulate pathways linked to tooth anomalies, including the TGFꞵ and Wnt signaling pathways, and those governing the pluripotency of stem cells, known to mediate various cellular processes, and interconnected with odontogenesis-related pathways. Furthermore, the analysis disclosed several pathways associated with tumors, including small cell lung and gastric cancer. These results were confirmed also by diseases and phenotypes enrichment evaluation. Moreover, cell network analysis disclosed that miRNAs are embedded and interconnected in networks associated with dental diseases and cancer development, thus confirming the functional enrichment analyses. Conclusion: In summary, our results offer a quantitative measure of the potential involvement of miRNAs in regulating pathways crucial for developmental processes, notably odontogenesis, and provide results suggesting potential association with oncogenesis processes as well.