胃癌组织中PTEN和p53基因的表达

THE EXPRESSION OF PTEN AND p53 GENE IN TISSUE OF GASTRIC CANCER

①目的 探讨抑癌基因PTEN和p5 3在胃癌组织中的表达及其与胃癌发生发展、临床病理特征之间的关系。②方法 应用免疫组织化学链霉亲和素方法 (SABC) ,检测PTEN和突变型p5 3基因在 6 5例胃癌组织、2 6例不典型增生胃黏膜、10例浅表性胃炎和 30例正常胃黏膜组织中的表达。③结果 胃癌组织中PTEN、突变型p5 3基因的阳性表达率分别为 4 8%、6 5 % ,不典型增生胃黏膜中PTEN、突变型p5 3基因的阳性表达率为 85 %、31% ,突变型p5 3基因在正常胃黏膜和浅表性胃炎组织中不表达 ,PTEN基因在正常胃黏膜和浅表性胃炎组织中全部呈阳性表达。胃癌组织中PTEN基因、p5 3基因的表达与其在正常胃黏膜组织、不典型增生胃黏膜、浅表性胃炎组织中的表达差别有显著性 (uc=2 .6 1～ 4 .5 2 ,P <0 .0 5 ) ;随临床分期、胃癌分化程度降低、浸润深度加深、淋巴结的转移 ,突变型p5 3基因的阳性表达率逐渐上升 (χ2 =4 .388～ 8.76 4 ,P <0 .0 5 ) ,PTEN基因的阳性表达率逐渐降低 (χ2 =5 .4 91～ 8.0 2 0 ,P <0 .0 5 ) ;PTEN基因表达阳性的胃癌组织中突变型p5 3基因的阳性表达率显著低于PTEN基因表达阴性的胃癌组织 (χ2 =9.81,P <0 .0 5 )。④结论 PTEN和p5 3基因的异常表达与胃癌的发生有关 ;PTEN和p5

Objective\ To study the expression of cancer suppressing genes, PTEN and p53, in gastric cancer and their relationship with the occurrence and clinicopathological features of the disease.\ Methods\ The expression of PTEN and mutant type p53 gene was detected by immunohistochemistry SABC method in 65 specimens of gastric cancer, 26 of atypical hyperplasia of gastric mucosa, 10 of superficial gastritis and 30 of normal gastric mucosa.\ Results\ The positive rates of expression of PTEN and mutant type p53 gene in gastric cancer were 48% and 65%, respectively, those in atypical hyperplasia of gastric mucosa were 85% and 31%, respectively. Mutant type p53 gene did not express in normal gastric mucosa and superficial gastritis. PTEN gene expressed in all specimens of gastric mucosa and superficial gastritis. The difference of PTEN gene expression was significant between cancer and normal gastric mucosa ( u c=2.61-4.52,P <0.05). The positive rates of mutant type p53 increased with advanced clinical staging, poor differentiation, deep invasion and lymph node metastasis( χ 2=4.388-8.764, P <0.05),while for PTEN gene, the positive rate decreased( χ 2=5.491-8.020,P <0.05). The expression of PTEN gene inversely correlated with the expression of mutant type p53 gene.\ Conclusion\ The abnormal expression of PTEN and p53 gene is related to tumorigenesis, they can be used as a parameter for the judgement of biological behavior of the cancer. PTEN and p53 gene play synergistic action in the occurrence and development of gastric cancer.