牙龈癌PTEN基因启动子区甲基化状态与鳞癌分级的分析研究

Relationship between the Methylation Status of PTEN Gene Promoter Region and the Differentiation of Squamous Cell Carcinoma of Gingiva

探讨第10号染色体丢失性的磷酸酶——张力蛋白同源基因(PTEN)启动子甲基化水平和蛋白表达水平与牙龈癌癌症细胞分化程度的关系。用甲基化特异性PCR法检测牙龈癌组织中PTEN基因启动子甲基化的状态,免疫组化法检测石蜡组织中PTEN的蛋白表达情况。结果牙龈癌组织中发生PTEN基因甲基化的频率为56.67%,其中高分化组甲基化频率为20%,中分化组为50%,低分化组为100%,组间差异具有统计学意义(P<0.05),PTEN甲基化频率与其细胞分化程度密切相关。说明牙龈癌中PTEN基因可出现启动子甲基化,且低分化组牙龈癌PTEN甲基化频率更高,同时细胞内PTEN蛋白表达显著下调甚至缺失,为牙龈癌的靶向治疗提供线索。

To investigate the relationship between the promoter methylation level of PTEN gene promoter region combined the protein expression level and the degree of differentiation of gingival carcinoma,methylation specific PCR method was applied to detect the methylation status of PTEN gene promoter region and the expression of PTEN protein in paraffin was detected by immunohistochemistry. The frequency of methylation in PTEN gene promoter region was 56. 67% in gingival carcinoma tussues,of which high differentiation group methylation frequency was 20%,the middle differentiation group was 50%,and low differentiation group was 100%,the difference between groups was statistically significant（ P〈 0. 05）. PTEN gene methylation frequency was closely related to the grade of gingival carcinoma. It is conclused that tissues of gingival carcinoma appeared promoter methylation of PTEN gene,meanwhile poorly differentiated groups of gingival carcinoma showed higher frequency of PTEN gene methylation,also intracellular PTEN protein expression was significantly downregulated or absent. The study provided clues for targeted therapy of carcinoma of gingiva of the target.