Down-regulated expression of CD44 variant 6 in oral squamous cell carcinomas and its relationship to regional lymph node metastasis.

The expression of the adhesion molecule CD44 variant 6 (CD44v6) was studied immunohistochemically on 38 oral squamous cell carcinomas (SCCs) and 10 biopsies of healthy oral mucosa. The relationship between the expression of CD44v6 and regional lymph node metastasis was also investigated. The expression of CD44v6 was apparently down-regulated in oral SCC, but not in normal oral mucosa. Carcinomas expressing lower levels of CD44v6 exhibited more frequent regional lymph node metastasis. The expression of CD44v6 showed no statistically significant relationship to the degree of differentiation, but tended to be down-regulated in poorly differentiated carcinoma. No significant relation was found between the expression of CD44v6 in primary and metastatic lesions.