A preliminary microarray assay of the miRNA expression signatures in buccal mucosa of oral submucous fibrosis patients.

OBJECTIVES: The objectives of this study are threefold: First is to perform a preliminary microarray analysis of miRNA expression profile to filter out differentially expressed miRNA in oral submucous fibrosis, second is to perform a bioinformatics analysis to identify miRNA-specific predicted genes, and third to retrieve those miRNAs from literature and account for the findings of our investigations. METHODS: Buccal mucosa samples from three clinically evident OSF patients and three normal volunteers were collected. Agilent Human miRNA microarray experiments were carried out to analyze the miRNA expression profile in both OSF and normal tissues. To identify molecular pathways potentially altered by expression of miRNAs, DAVID software was used. This application performs an enrichment analysis of multiple miRNA target genes comparing each set of miRNA targets to known KEGG pathway. RESULTS: A total of 11 unique miRNAs were differentially expressed. The overexpressed miRNAs were hsa-miR-455-3p, hsa-miR-455-5p, and hsa-miR-623, and underexpressed miRNAs were hsa-miR-1290, hsa-miR-3180-3p, hsa-miR-4792, hsa-miR-509-3-5p, hsa-miR-5189, hsa-miR-610, hsa-miR-760, and hsa-miR-921. Six miRNAs namely miR-455, miR-760, miR-623, miR-610 and miR-509-3-5p were selected. CONCLUSION: This study shows that miRNA chip can be used for high-throughput screening of miRNA. Target prediction and annotation of the miRNAs demonstrated that the binding, metabolic process, molecular, and cellular process are the most common functions of the predicted targets of these newly identified miRNAs.

Primary intraosseous ACC of mandible of possible salivary origin: A rare clinical entity.

INTRODUCTION: Adenoid cystic carcinoma (ACC) is a malignant tumor mainly of salivary origin which is well known for its deceptively benign histologic appearance characterized by indolent, locally invasive growth with high propensity for local recurrence and distant metastasis. PRESENTATION OF CASE: An unusual case of a 23-year-old woman was reported in our hospital. After investigations, it showed that it is a second primary intraosseous lesion of mandible that occurred subsequently after ACC of parotid gland. After diagnosis was established, resection of tumor and reconstruction with a free fibula flap was performed. Ten months follow-up showed no signs of recurrence or metastasis. DISCUSSION: Among the salivary neoplasms, adenoid cystic carcinoma is very rare and intraosseous lesions are even rarer. We found a total of 26 cases of primary ACC of the mandible reported in the literature. Pain and swelling were the most frequent symptoms. CONCLUSION: This case illustrates two key facts. First, not all cystic lesions are necessarily metastatic or recurrence. Second is, even though the exact origin of this tumor is unknown, central salivary gland tumors should be considered in the differential diagnosis of cystic lytic lesions in the mandible.