早期胃癌及癌旁组织P53及PCNA蛋白表达的意义

[目的]探讨抑癌基因蛋白P53及PCNA蛋白在早期胃癌发生中所起的作用。[方法]应用免疫组化技术检测28例早期胃癌及其癌旁组织的PCNA及抑癌基因蛋白P53的表达情况，采用t检验和70检验统计分析。[结果]（1）正常胃黏膜、肠上皮化生黏膜、异型增生病灶及早期胃癌的PCNA阳性细胞率分别为11．7％、20．3％、36．4％和49．2％，细胞增殖活性逐渐增高，各组间有显著差异（P〈0．05）；在异型增生黏膜中，随异型程度的增高，增殖活性也逐渐升高，轻度、中度、重度病变的PCNA阳性细胞率分别为29．4％、35．5％和43．2％，各组与癌灶的PCNA阳性细胞率（49．2％）相比有显著差异（P〈0．05）。（2）抑癌基因蛋白P53在轻度、中度、重度异型增生及早期胃癌中可见表达，阳性率分别为11.1％、14．3％、30．0％和42．4％，各组间相比无显著差异（P〉0．05）；而正常胃黏膜、肠上皮化生黏膜P53未见表达。（3）抑癌基因蛋白P53阳性表达的病例PCNA阳性细胞率明显高于P53阴性表达的病例（P〈0．05）。[结论]PCNA及抑癌基因蛋白P53在胃癌的发生中起重要的作用。

Significance of expression of P53 and PCNA proteins in primary gastric cancer and para-cancerous tissue

[Objective] To study tumour suppressor gene P53 protein and PCNA protein expression in primary gastric cancer and define whether they were associated with the stomach carcinogenesis.[Methods] This article examines P53 and PCNA protein expression in 28 cases of primary gastric cancers and para-cancerous tissue by immunohistochemistry.[Results](1)The percentages of PCNA-positive cells from normal(11.7%),intestinal metaplasia(20.3%) and dysphasia(36.4%) to early gastric cancer(49.2%) increases gradually,and the differences among them is very obvious(P<0.05);As to dysphasia,the proliferative activity from mild((29.4%)) and moderate(35.5%) to severe(43.2%) also increase gradually.There is apparent difference between each of them and primary cancer(P<0.05).(2) Positive staining of P53 protein only appears in the dysplasia and cancer.As to dysplasia,when the degree increases,positive staining of P53 protein also increases with it(mild,11.1%;moderate,14.3%;severe,30%);There is no apparent difference between severe dysplasia(30%) and cancer(42.4%)(P>0.05).(3)The proliferative activity of P53-positive cases is much higher than that of P53-negative cases.[Conclusion] Tumour suppressor gene P53 protein and PCNA take the important roles.