摘要
目的:检测胃癌组织中吲哚胺2,3双加氧酶(indoleamine2,3-dioxygenase,IDO)、增殖细胞核抗原(PCNA)、T细胞表面标志CD3、CD4和CD25的表达状况,探讨其在肿瘤细胞增殖、转移和免疫逃逸中的作用。方法:采用免疫组化染色及免疫荧光染色检测胃癌组织中IDO、PCNA、T细胞表面标志CD3、CD4和CD25的表达,分析IDO表达在肿瘤细胞增殖、转移和免疫逃逸中的作用。结果:1)肿瘤细胞和单个核细胞表面表达IDO;胃癌肿瘤组织IDO的阳性表达率为73.33%,高于癌旁组织。肿瘤组织内IDO高表达与PCNA高表达显著相关,χ2=4.35,P<0.05。2)胃癌肿瘤组织内CD3阳性表达率为37.67%,低于癌旁对照组,χ2=4.45,P<0.05。3)胃癌组织中可见CD4+CD25+调节性T细胞(Treg)。4)胃癌患者中转移组IDO阳性表达率为86.36%,无转移组表达率为60.0%,转移组IDO阳性表达率高于无转移组,P=0.01。结论:胃癌细胞高表达IDO,能抑制T细胞活化、增殖和向肿瘤组织内的浸润,在肿瘤组织内造成免疫抑制,从而促进肿瘤的增殖和转移。肿瘤组织中CD4+CD25+Treg细胞参与IDO引发胃癌肿瘤免疫耐受的过程,发挥免疫抑制作用。
OBJECTIVE: To investigate the expression of IDO (indoleamine 2,3-dioxygenase) in gastric cancer, as well as its clinical significance. METHODS:Expressions of IDO, PCNA, CD3, CD4 and CD25 were detected by immunochemistry and immunofluorescence technique in gastric cancer. RESULTS: 1)The positive rate of IDO expression in GC cases (73.33%) was higher than that in Para cases (61.90%). IDO was detected in membrane on cancer cells and mononuclear cells. Moreover, the over expression of IDO in cancer tissue was relative with over expression of PCNA,Х^2 =4.35,P〈0.05. 2) The positive rates of CD3 expression in GC cases and Para cases were 37.67% and 66.67% respectively. There was a significant difference between the two groups, Х^2=4.45, P〈0.05. 3)CD4^+CD25^+ T cells were exanimated in gastric cancer. 4)The positive rates of IDO expression was 86.36% with lymph node metastasis of 30 cases gastric cancer, and 60.0% without lymph node metastasis (P = 0.01 ). CONCLUSIONS: Strong expression of IDO in gastric cancer can inhibit activation, proliferation and infiltration of T cells, which results in the environment of immunosuppression in cancer tissue and encourage proliferation and metastasis of cancer cells. CD4^+ CD25^+ T cells in cancer is related to the expression of IDO, which indicates Treg participates immune tolerance induced by IDO.
出处
《中华肿瘤防治杂志》
CAS
2008年第15期1155-1158,共4页
Chinese Journal of Cancer Prevention and Treatment
关键词
胃肿瘤
色氨酸加氧酶
肿瘤逃逸
gastric neoplasms
tryptophan oxygenase
tumor escape