Expressions and clinical significance of P-gp,GST-π and TopoII in colorectal cancer

OBJECTIVE:To study the clinical significance of P-glycoprotein(P-gp),glutathione-S-trannsferaseπ(GST-π)and DNA topoisomerase Ⅱ(TopoⅡ)expressions in colorectal carcinoma tissue.METHODS:The expressions of P-gp,GST-π and TopoⅡ in 84 cases of colorectal carcinoma and 20 cases of normal tissues were detected by SP immunohistochemical technique,and its correlation with clinical pathologic characteristics of carcinoma was explored.RESULTS:The expression rates of P-gp(71.4%,60/84)and GST-π(75%,63/84)in colorectal carcinoma were all higher than those in normal tissues(χ2 was 6.91 and 3.14,P0.05),while the expression rate of TopoⅡ(45.3%,38/84)in colorectal carcinoma was lower,χ2=0.382,P0.05.The expression of P-gp was associated with clinical stage of tumor.The expression rate of P-gp on high clinical stage was 86.7%(39/45)and higher than that of low clinial stage(65.5%,19/29),χ2=5.28,P0.05.The expression rates of P-gp and GST-π were 87.5%,80.7%,54.5% and 87.5%,82.5%,54.5% in well-differentiated adencarcinoma,moderately differentiated adencarcinoma and poorly differentiated adenocarcinoma respectively.The expression arets of Topo Ⅱ were 37.5%,45.6% and 63.6%.The expression rates of P-gp(87.5%,80.7% and 54.5%)and GST-π(87.5%,82.5% and 54.5%)in group with lymph metastasis were significantly higher than those in group without lymph node metastasis(37.5%,45.6% and 63.6%),P0.05.CONCLUSIONS:P-gp,GST-π,and TopoⅡ play important roles in the primary MDR of colorectal carcinoma.The determination of P-gp,GST-π and TopoⅡ may be useful for the estimation of prognosis and the establishment of chemical therapy regimen in colorectal carcinoma.