Aberrations of the tumor suppressor p53 gene and p53 protein in solar keratosis in human skin.

Aberrations of the p53 gene in 27 solar keratoses were examined by the polymerase chain reaction and single-strand conformation polymorphism and DNA sequencing analyses. In a series of Japanese patients, eight of 27 cases (30%) of solar keratosis showed structural abnormalities of the p53 gene. Six of eight aberrations of p53 gene were determined to be single nucleotide substitutions, and five of these were located at a dipyrimidine site. In solar keratosis, noticeable mutations were C to T in three cases, and one each of C to A and T to C nucleotide changes. p53 protein was detected immunohistochemically in the nuclei of six of 27 cases (22%) of solar keratosis. Nuclear staining for p53 protein was only significantly correlated with the presence of missense mutation of p53 gene (p < 0.01). Aberrations of the p53 gene in solar keratosis may be a marker to predict early cancerous lesions.