Oral lichen planus （OLP） is a chronic inflammatory disorder and premalignantlesion, of which the mechanisms are still obscure. In the present study, the expression levels of miR-96/182/183 cluster, miR-203, miR-375, and miR-769-5p in both tissues and exfoliative cells of OLP patients as well as healthy volunteers were detected, differentially expressed miRNAs were identified and their correlation with OLP was evaluated by a biplot method. Experimental results show that miR-203 is significantly up-regulated in patient lesion tissues in comparison to volunteer mucosa tissues. Moreover, the contra- dictory insignificant expression changes of miR-203 as well as miR-96/182/183 cluster in comparisons of exfoliative cell samples suggest that different cell compositions in OLP lesion have distinct miRNA regulation, which accords with the histological heterogeneity of OLP. Finally, biplot analyses indicate the expression of miR-203 and miR-96/182/183 cluster are positively correlated in patient lesions. These results provide miR-203 as a molecular indicator of heterogeneity of OLP, and also a potential diagnostic biomarker or therapeutic target that deserves further studies.
