良恶性胃黏膜中p21^(ras)、表皮生长因子受体和p53蛋白的表达及意义

Expression of p21^(ras),epidermal growth factor receptor and p53 protein in benign and malignant gastric mucosa.

目的研究p21ras、表皮生长因子受体(EGFR)和p53突变蛋白在良恶性胃黏膜组织中的表达及其对胃癌早期诊断的意义。方法应用免疫组织化学方法对31例胃癌、49例癌前病变、21例萎缩性胃炎和28例正常胃黏膜组织中的p21ras、EGFR和p53突变蛋白的表达进行检测。结果31例胃癌组中,p21ras、EGFR和p53突变蛋白的阳性表达率分别为64.5%、54.8%和32.3%;49例癌前病变组中,p21ras、EGFR和p53突变蛋白的阳性表达率分别为59.2%、53.1%和22.4%;癌前病变组和胃癌组间3种基因蛋白的阳性表达率差异均无显著性(均为P>0.05),但均显著高于正常胃黏膜组(P<0.05或P<0.01)。结论胃癌和癌前病变胃黏膜组织中存在多种基因的表达异常,检测胃黏膜中p21ras、EGFR和p53蛋白对胃癌早期诊断的意义不大。

Objective To investigate the expression of p21^ras, epidermal growth factor receptor （EGFR） and p53 in benign and malignant gastric mucosa and their significance for the early diagnosis of gastric cancer. Methods The expression of p21^ras, EGFR and p53 in 31 stomach cancers ,49 precancerous lesions ,21 atrophic gastritis and 28 normal gastric mucosa were studied using immunohistochemical staining. Results The positive rate of p21^ras ,EGFR and p53 in gastric cancer was 64.5% ,54.8% and 32.3% respectively. The positive rate of p21^ras, EGFR and p53 in precancerous lesions were 59.2% ,53. 1% and 22. 4%, respectively. There was no significant difference in three proteins expression between stomach cancer and precancerous lesions （ P 〉 0.05 ） but their levels were higher than those of normal gastric mucosa （ P 〈 0.05 or 0.01 ）. Conclusion Many gene abnormalities are present in gastric cancers and precancerous lesions. The expression of p21^ras ,EGFR and p53 protein in gastric mucosa may not be useful markers for diagnosis of early gastric cancer.