Heterogeneity of miRNAs in Salivary Gland Neoplasms: An Exploratory Pilot Study

Introduction MicroRNAs (miRNAs) are small RNAs that have been associated with tumourigenesis and tumour progression and that play an important role in the pathogenesis of salivary gland neoplasms. The aim of this study was to evaluate the global miRNA expression profile in a sample of salivary gland neoplasms. Methods Cases of pleomorphic adenoma ( n = 4), adenoid cystic carcinoma ( n = 4) and mucoepidermoid carcinoma ( n = 4) were studied by real‐time RT‐PCR. Results The main up‐regulated miRNAs were hsa‐miR‐373, hsa‐miR‐675, hsa‐miR‐508, hsa‐miR‐1290 and hsa‐miR−483‐3p, while hsa‐miR‐105 and hsa‐let‐7f‐1 were among the most down‐regulated miRNAs compared to the normal salivary gland. Hsa‐miR‐106b, hsa‐miR‐142‐5p, hsa‐miR‐622, hsa‐miR‐642, hsa‐miR‐574‐3p and hsa‐miR‐486 were significantly differentially expressed ( p < 0.05) when each neoplasm and normal glandular tissue were compared. Conclusion This study described the global molecular signature of miRNAs in benign and malignant salivary gland neoplasms and provided preliminary evidence of miRNA dysregulation, suggesting a potential association between specific miRNA signatures and molecular pathways implicated in tumour progression.