FEULGEN HYDROLYSIS PROFILES AND ACID-LABILE DNA IN ORAL SQUAMOUS-CELLCARCINOMA

The full Feulgen hydrolysis profiles of healthy and malignant oral epi thelial cells were compared by measuring the staining density of nucle i using microdensitometry after varying hydrolysis times, Malignant nu clei contained significantly increased levels of acid-labile DNA. The relative amounts of the rapidly hydrolysable fraction were compared af ter 5 min hydrolysis for exfoliating epithelial cells from healthy ora l mucosa, healing chronic ulcers and squamous cell carcinomas. Althoug h the latter exhibited a wide range of values, analysis of variance sh owed significant differences (P< 0.05) between healthy control and ulc er groups compared to oral carcinoma, The relative proportion of highl y acid-labile DNA in malignant nuclei showed a significant positive co rrelation with mitotic score (P < 0.01) but no significant correlation with nuclear area, It was concluded that since the susceptibility of DNA to acid hydrolysis probably reflects functional differences in nuc lear activity between cells, estimation of the highly acid-labile frac tion may have diagnostic and/or prognostic value.