Expressive levels of MUC1 and MUC5AC and their clinicopathologic significances in the benign and malignant lesions of gallbladder

Abstract

This article is intended to make a study on the expressive levels of mucin core proteins (MUC1 and MUC5AC) and detect their clinicopathologic significances in the benign and malignant lesions of gallbladder. EnVision immunohistochemical method for determining the expressions of MUC1 and MUC5AC was used in routinely paraffin-embedded sections of surgically resected specimens from gallbladder adenocarcinoma (n = 108), peritumoral tissues (n = 46), adenoma (n = 15), and chronic cholecystitis (n = 35). The positive rate of MUC1 expression was significantly higher in gallbladder adenocarcinoma than that in peritumoral tissues (χ(2) = 16.49, P < 0.01), adenoma (χ(2) = 7.40, P < 0.01), and chronic cholecystitis (χ(2) = 28.57, P < 0.01), while the positive rate of MUC5AC expression was significantly lower in gallbladder adenocarcinoma than that in peritumoral tissues (χ(2) = 12.83, P < 0.01), adenoma (χ(2) = 4.22, P < 0.05), and chronic cholecystitis (χ(2) = 20.25, P < 0.01). The positive cases of MUC1 and the negative ones of MUC5AC in the benign lesions showed moderate- or severe-dysplasia of gallbladder epithelium. The positive rates of MUC1 were significantly lower in gallbladder adenocarcinomas with maximal diameter of mass <2 cm, no metastasis of lymph node, and no invasiveness of regional tissues (P < 0.05 or P < 0.01) than those in gallbladder adenocarcinomas with maximal diameter of mass >2 cm, metastasis of lymph node, and invasiveness of regional tissues (P < 0.05 or P < 0.01). However, the positive rates of MUC5AC were significantly higher in the highly differentiated adenocarcinoma with maximal diameter of mass <2 cm than those in the low-differentiated adenocarcinoma with maximal diameter of mass ≥2 cm. Univariate Kaplan-Meier analysis showed that increased expression of MUC1 (P = 0.064) or decreased expression of MUC5AC (P = 0.017) was associated with decreased overall survival. Multivariate Cox regression analysis showed that decreased expression of MUC5AC (P = 0.008) was an independent prognostic predictor to gallbladder adenocarcinoma. The expression of MUC1 and MUC5AC might be closely related to the carcinogenesis, clinical biological behaviors, and prognosis of gallbladder adenocarcinoma.