口腔扁平苔癬の悪性化に関する免疫組織学的検討

podoplanin

北海道歯学会

北海道歯学雑誌

Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease and considered to be a potentially premalignant disorder. The pathogenesis of OLP is unclear, but subepithelial inflammatory reaction induced by stimuli including mechanical stress or dental materials have been thought to cause apoptosis of epithelial cells. The mechanism of malignant transformation of OLP is also controversial. The objective of this study was to evaluate the risk factors and to elucidate the mechanism of malignant transfomation of OLP. The target was 54 patients who had been pathologically diagnosed with OLP at Hokkaido University Dental Hospital. We investigated clinical background factors including age, gender and region. Immunohistochemical experiments were performed with anti-CD3, anti-CD8, and anti- CD20 antibody for subepithelial lymphocytes, with anti-CD68 antibody for intraepithelial dendritic cells and anti-p53, Ki-67 and anti-podoplanin antibody for epithelial cells. 3 cases were malignantly transformed in 54 cases. In the clinical background factors, although there was no difference among age or gender, OLP on the tongue seemed to have malignant potential. Immunohistological studies revealed that there was no difference of CD20, CD8, CD3, CD68, p53, and Ki-67positive cells between control and transformed groups. On the other hand, podoplanin positive cells and their distribution were significantly correlated with a risk of malignant transformation (p<0.05). These results indicated that aberrantpodoplanin expression and distribution correlate with malignant transformation of OLP and analysis of podoplanin staining on OLP could be a useful tool to predict termination.