结直肠癌组织谷胱甘肽-S-转移酶π的表达和其血浆水平的关系

Expression of Glutathione-S-transferase π in colorectal carcinoma and the relation with its plasma levels

目的:探讨结直肠癌中谷胱甘肽S转移酶π(GlutathioneStransferaseπ,GSTπ)的表达和血浆GSTπ的水平,并对两者进行比较。方法:我们对48例结直肠癌(17例患者手术前进行过化疗,其中9例行1次化疗,8例行2次以上化疗),21例结直肠息肉患者和18例正常对照者进行研究。应用免疫组化方法检测标本组织的GSTπ表达情况,用酶联免疫吸附法(ELISA)测定血浆中的GSTπ水平。结果:GSTπ在结直肠癌组织的阳性表达率为6458%(31/48),比正常对照组和结直肠腺瘤组GSTπ阳性表达明显增高,P<005。GSTπ的表达与性别、年龄、肿瘤位置、肿瘤大小、淋巴结转移、分化程度、局部浸润深度、远处转移、Duke′s分期、CEA和预后均无关。从正常对照组到结直肠腺瘤组再到结直肠癌组,血浆中的GSTπ水平呈现递增的趋势。辅助化疗后,结直肠癌组的血浆GSTπ水平明显下降,P<005。检测结直肠癌GSTπ时,免疫组化和ELISA两种方法间有相关关系(MantelHaenszelχ2=6475,P=0011)。结论:结直肠癌中GSTπ表达增加,应用免疫组化和ELISA方法都可以有效检测。

OBJECTIVE:To elucidate the expression of GST-π in colorectal carcinoma and the relation with plasma GST-π levels. METHODS:All cases were obtained from the general surgery department of Shandong Provincial Hospital. Their clinical records and surgical pathology reports were collected.The immunohistochemical staining was performed in 48 cases of colorectal carcinoma as well as 21 of colorectal adenoma and 18 of normal control specimens, by using antibodies to GST-π. Plasma GST-π levels were measured by the enzyme-linked immunosorbent assay (ELISA) method. Statistical analyses were performed with SPSS 11.0 for Windows. RESULTS:The positive percentage of GST-π in colorectal carcinoma was higher than that of colorectal adenomas and the normal controls. No relation was estabilshed between GST-π and clinicopathological features.The levels of GST-π in blood plasma increased in turn from normal controls to colorectal adenomas to colorectal carcinoma. The plasma GST-π levels in postchemothrapy lower than those in prechemothrapy for colorectal carcinoma. There was a significant correlation between the expression and levels of GST-π with the immunohistochemical staining and ELISA. (Mantel-Haenzel χ2=6.475,P=0.011).CONCLUSION:The expression of GST-π increased in colorectal carcinoma immunohistochemical staining and ELISA can measure the levels of GST-π,but plasma GST-π with ELISA method can be an index of monitoring chemotherapy effect. Chin J Cancer Prev Treat,2005,12(2):95-98