Expression of p57~(kip2) and cyclin D1 protein in esophageal cancer tissues and their significance

Purpose To investigate the expression and significance of p57kip2 in the esophageal cancer tissue,and the relationship with cyclin D1 protein.Methods Immunohistochemical SP method was used to detect the expression of p57kip2 and cyclin D1 protein in 50 cases of esophageal cancer tissue and 15 cases of normal esophageal tissue,the change of DNA content and cell cycle distribution were analyzed by flow cytometry(FCM).Results The percentage of p57kip2 postive-expression in esophageal cancer tissue was lower than that in normal tissue(P0.01).There was a significant correlation between the expression of p57kip2 protein and the tumor cell differentiation,the depth of invasion and the lymph node metastasis(P0.05);The percentage of cyclin D1 positive-expression in tumor tissue was higher than that in nomal tissue(P0.01),and there was a correlation between the expression of cyclin D1 and the depth of invasion,the lymph node metastasis(P0.05),but was not correlated with the tumor cell differentiation(P0.05).There was negative correlation berween expression of p57kip2 and cyclin D1(r=-0.429,P0.01).Flow cytometry(FCM) showed that the DNA content and heteroploid cell increased in the esophageal cancer.The percentage of cells in G0/G1 phase decreased but increased in S and G2/M phase,the proliferation index(PI)increased in esophageal cancer tissues than that in normal tissues.Conclusions The decreased expression of p57kip2 protein may related to carcino genesis and progress of esophageal cancer,and the combined detection of p57kip2 and cyclin D1 protein them may serve as useful prognostic markers for the esophageal cancer.