Expression of 8-oxodG in Oral Leukoplakia / 沈阳医学院学报

ABSTRACT

Objective:To study the expression of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in oral leukoplakia for clarifying the role of oxidative DNA damage in the development of oral leukoplakia. Methods:Immunofluorescence labeling method was used to examine the expression of 8-oxodG,a marker of oxidative DNA damage,and the expression of tumor suppressor gene, P53 protein in oral epithelium of normal oral mucosa and biopsy specimens of leukoplakia. Results:In specimens of oral leukoplakia, HE staining showed infiltration of inflammatory cells, hyperkeratosis and epithelial dysplasia. Immunofluorescence labeling study demonstrated that the accumulation of 8-oxodG apparently increased in the oral epithelium of patients with leukoplakia,whereas little or no immunoreactivity was observed in normal oral mucosa. Expression of P53 protein was also observed in oral epithelium of patients with oral leukoplakia. The immunoreactivity of 8-oxodG and P53 was stronger in patients with oral leukoplakia than that in normal oral mucosa (P<0.01) . Moreover,the immunoreactivity increased with the development of disease (r=0.773, P<0.01) . Conclusions:The oxidative DNA damage contributes to the development of oral leukoplakia. 8-oxodG may be a risk predictive marker for oral leukoplakia.