P53 PROTEIN EXPRESSION IN SQUAMOCELLULAR CARCINOMAS OF THE LIP

Twenty-six cases of squamocellular carcinomas of the lip were immunost ained for P53 protein. Nuclear accumulation of p53 protein was observe d in 88% of the 26 carcinomas, in 64% of adjacent ''normal'' epitheliu m and in all four cases with adjacent atypical squamous epithelium. 93 % of the specimens (13/14) with p53 protein accumulation in ''normal'' epithelium demonstrated evidence of solar elastosis. UV radiation may induce p53 gene mutation as an early event in the neoplastic transfor mation.