Review of MicroRNA Deregulation in Oral Cancer. Part I

OBJECTIVES: Oral cancer is the sixth most common malignancy worldwide. Cancer development and progression requires inactivation of tumour suppressor genes and activation of proto-oncogenes. Expression of these genes is in part dependant on RNA and microRNA based mechanisms. MicroRNAs are essential regulators of diverse cellular processes including proliferation, differentiation, apoptosis, survival, motility, invasion and morphogenesis. Several microRNAs have been found to be aberrantly expressed in various cancers including oral cancer. The purpose of this article was to review the literature related to microRNA deregulation in the head and neck/oral cavity cancers. MATERIAL AND METHODS: A comprehensive review of the available literature from 2000 to 2011 relevant to microRNA deregulation in oral cancer was undertaken using PubMed, Medline, Scholar Google and Scopus. Keywords for the search were: microRNA and oral cancer, microRNA and squamous cell carcinoma, microRNA deregulation. Only full length articles in the English language were included. Strengths and limitations of each study are presented in this review. RESULTS: Several studies were identified that investigated microRNA alternations in the head and neck/oral cavity cancers. Significant progress has been made in identification of microRNA deregulation in these cancers. It has been evident that several microRNAs were found to be deregulated specifically in oral cavity cancers. Among these, several microRNAs have been functionally validated and their potential target genes have been identified. CONCLUSIONS: These findings on microRNA deregulation in cancer further enhance our understanding of the disease progression, response to treatment and may assist with future development of targeted therapy.