LAUSR

Objective To examine the CD146/METCAM expression on keratinocytes in normal oral mucosa (NOM), oral lichen planus (OLP), oral epithelial dysplasia (OED), and oral squamous cell carcinoma (OSCC). Subjects and methods Immunohistochemical examination of CD146 was performed on 80 specimens, divided into 20 cases from each group. The number of CD146 + keratinocytes was quantitatively assessed together with the staining intensity. Results The mean percentage of CD146 + keratinocytes was 19.04±15.32, 59.40±24.48, 60.04±28.87, and 22.13±21.03 in NOM, OLP, OED, and OSCC, respectively. The mean percentages of CD146 + keratinocytes in OLP and OED were significantly higher than those of NOM and OSCC ( p ≤0.001). Most OED (55%) and OLP (60%) showed strong and moderate staining intensity, respectively, while NOM (50%) and OSCC (45%) predominantly expressed CD146 at mild intensity. Conclusions This is the first study to examine CD146 expression in OLP and OED. CD146 is upregulated in OLP and OED but downregulated in OSCC. The alteration in CD146 may be involved in the immunoregulatory response of OLP and the early event of oral carcinogenesis. The loss of this protein may underlie the progression of OED into invasive OSCC. Clinical relevance Overexpression of CD146 protein may play a role in the pathophysiology of OLP and OED.