Expression of Bcl-2 protein in human laryngeal keratoses.

Strong Bcl-2 immunostaining was detected in 2 of 21 samples of human laryngeal keratoses, one of which contained neither p53 gene mutation nor human papillomavirus sequences nor significant levels of p53 protein. The other 19 samples including 6 cases with moderate or strong p53 staining were Bcl-2-unreactive or had minimal Bcl-2 reactivity similar to that observed in normal samples. Minimal Bcl-2 staining in 5 samples with moderate or severe dysplasia was only seen in the adjacent nondysplastic area. Our study shows that (1) some laryngeal keratoses strongly express Bcl-2 protein, (2) Bcl-2 expression does not appear to be dependent on p53, and (3) moderate or severe dysplasias may occur despite a decline in Bcl-2 expression.