Expressive levels of MK-1 antigen and regenerating gene IV and its clinicopathological significance in the benign and malignant lesions of gallbladder

Abstract

Objective To study the expression levels of MK-1 antigen and regenerating gene Ⅳ (RegⅣ) and their clinicopathological significance in the benign and malignant lesions of gallbladder.Methods EnVisionTM immunohistochemical method for determining the expression of MK-1 and RegⅣ was used in routinely paraffin-embedded sections of surgically resected specimens from gallbladder adenocarcinoma ( n =108 ), peritumoral tissues ( n =46), adenomatous polyp ( n =15 ), and chronic cholecystitis (n =35). Results The positive rate of MK-1 or RegⅣ expression was significantly higher in gallbladder adenocarcinoma than that in peritumoral tissues (x2MK-1 =18.76, P ＜ 0. 01 ;x2RegⅣ =9.92, P ＜ 0. 01 ),adenomatous polyp (x2MK-1 =9. 49, P ＜ 0. 01 ;x2RegⅣ =8.59, P ＜ 0. 01 ) and chronic cholecystitis (x2MK-1 =24. 11,P ＜0. 01;x2RegⅣ =19. 24,P ＜ 0. 01 ). The positive cases of MK-1 and/or RegⅣ in the benign lesions showed moderate-or severe-atypical hyperplasia of gallbladder epithelia. The positive rate of MK-1 was significantly higher in the cases of well-differentiated adenocarcinoma, no-metastasis of lymph node,and no-invasiveness of regional tissues than that in the cases of low-differentiated adenocarcinoma, metastasis of lymph node, and invasiveness of regional tissues in gallbladder adenocarcinoma ( P ＜ 0. 05 or P ＜0. 01 ). The positive rate of RegⅣ was significantly lower in the cases of well-differentiated adenocarcinoma,no-metastasis of lymph node, and no-invasiveness of regional tissues than those in the cases of low-differentiated adenocarcinoma, metastasis of lymph node, and invasiveness of regional tissues in gallbladder adenocarcinoma (P ＜0. 05 or P ＜0. 01 ). Unitivariate Kaplan-Meier analysis revealed that the decreased expression of MK-1 (P ＜0. 01 ) or increased expression of RegⅣ (P ＜0. 01 ) was associated with decreased overall survival. Multivariate Cox regression analysis demonstrated that the decreased expression of MK-1 (P ＜ 0. 05 )and/or increased expression of RegⅣ (P ＜0. 01 ) was an independent bad-prognostic predictor in gallbladder adenocarcinoma. Conclusion The expression of MK-1 and/or RegⅣ might be closely related to the carcinogenesis, clinical biological behaviors, and prognosis of gallbladder adenocarcinoma. Key words: Gallbladder neoplasms; MK-1 ; Regenerating gene Ⅳ