胃癌及癌前病变P—糖蛋白的表达及意义

目的：研究胃癌及癌前病变组织中P－糖蛋白（P－glycoprotein,P-gp)的表达。方法：用免疫组化S－P法对65例胃癌，20例萎缩性胃炎伴肠上皮化生，18例不典型增生和10例正常胃粘膜中P－gp的表达进行检测。结果；20例胃癌（30．8％），3例萎缩性胃炎伴肠上皮化生（15．0％），3例不典型增生（16．7％）和1例正常胃粘膜（10．0％）呈阳性表达，胃癌与正常胃粘膜中P－gp的表达有显著性差异（P＜0．05）。胃癌中淋巴结转移及癌细胞浸润浆膜、浆膜外者P－gp表达率明显高于无淋巴结转移及浆膜内浸润者。结论：P－糖蛋白的表达与胃癌原发性耐药的产生有关，且对胃癌细胞的浸润、淋巴结转移可能有促进作用。

AN IMMUNOHISTOCHEMICALSTUDY ON THE EXPRESSION OF P-GLYCOPROTEIN IN GASTRIC CANCER AND PRECANCEROUS LESION

Objective:To investigate the expression of P-glycoprotein (P-gp) in gastric cancer and precancerous lesions.Methods:The expression of P-gp was investigated immunonistochemmically in the tissue speciments of 65 patients with gastric carcinoma,20 patients with atrophic gastritis and supcrvcnicnt intcstinal mctaplasia,18 paticnts with atypical hycrplasia of gastricmucosa and 10 normal persons.Results:The positive immunoreactivity for P-gp was detected in 20 samples of gastric carcinoma,3 samplcs of atrophic gastritis and supervennient intestind metaplasia 3 samples of atypical hyerplaia of gastric mucosa.The positive expression of P-gp in gastrci carcinoma and normal gastric mucosa were significantly different ( P <0.05).In patient with lymph node metastasis,P-gp positive rates were significantly higher than those in patiets without lymph node metastasis.The P-gp positive rates in the carcinoma with serous coat involvement were signifcantly higher than those in carcinoma with serous coat involvment were signifacantly higher than those in carcinoma without serous coat involvement.Conclusions:The expression of P-gp indicates there is primary drug resistance in gastric carcinoma.P-gp expression is a tardive event in the promotion and progression of gastric carcinoma.It maybe has the effect to motivate the diffusional transference and metastasis of gastric carcinoma.