EXPRESSION OF CD44S, CD44V5, CD44V6 AND CD44V7-8 IN BETEL QUID CHEWING-ASSOCIATED ORAL PREMALIGNANT LESIONS AND SQUAMOUS-CELL CARCINOMAS INTAIWAN

Aberrant expression of the cell surface adhesion molecule CD34 and its variant forms has been Shown to be associated with the invasive and m etastatic potential of cancer cells, and with poor prognosis in severa l types of cancers. Expression of CD34 standard (CD44s) and variant (C D44v) forms in oral squamous cell carcinoma (SCC), epithelial dysplasi a (ED), epithelial hyperkeratosis (EH) and normal buccal mucosa (NBM) have been examined using antibodies to CD44s, CD44v5, CD44v6 and CD44v 7-8. Positive CD44s, CD44v5, CD44v6 and CD44v7-8 staining was detected in all the specimens from NBM, EH and ED. Positive staining of CD44s, CD44v5, CD44v6 or CD44v7-8 was detected in 55 (88.7%), 48 (77.4%), 59 (95.2%) and 22 (35.5%) of the 61 SCC specimens, respectively. The pos itive staining of CD44v7-8 in oral SCC was significantly less than tha t in NBM (P<0.01). No significant correlation was found between CD44v7 -8 expression and daily or total consumption of betel quids or cigaret tes by the SCC patients. The 5-year survival rate for patients with CD 44v7-8-positive tumours was significantly higher than that for the CD4 4v7-8-negative group (P<0.03). These results indicate that loss of CD4 4v7-8 expression may be a valuable factor for determining prognosis in oral SCC patients.