良恶性胃黏膜中p21ras、表皮生长因子受体和p53蛋白的表达及意义

目的研究p21^ras、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p21^ras、EGFR和p53突变蛋白的表达进行检测。结果31例胃癌组中,p21^ras、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,p21^ras、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p21^ras、EGFR和p53蛋白对胃癌早期诊断的意义不大。

Expression of p21ras,epidermal growth factor receptor and p53 protein in benign and malignant gastric mucosa

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.