comparative study of expression of smad3 in oral lichen planus and normal oral mucosa

oral lichen planus (olp) is a chronic inflammatory disease of the oral mucosa which is considered by the world health organization (who) as a premalignant condition. one step in malignant development is so called epithelial mesenchymal transition (emt), a process whereby epithelial cells acquire mesenchymal characteristics. a factor known to induce emt is the transforming growth factor-β (tgf-β), which uses the smad proteins as mediators for its signaling. the aim of this study was to compare the expression of smad 3 in oral lichen planus and normal oral mucosa. this descriptive analytic study was performed on 30 patients with olp (21 women and 9 men with mean age of 45.23± 2.44 years) and 20 normal oral mucosa (14 women and 6 men with mean age of 46.95± 2.21 years). the samples were studied by immunohistochemical staining. data were analyzed with paired t-test and wilcoxon test by spss software. expression of smad3 in olp samples and normal oral mucosa was different. this difference was statistically significant (p< 0.001). the apparently higher expression of smad 3 in oral lichen planus compared to normal oral mucosa might help to discuss its higher potential for malignant transition.