Expression of β-catenin in PanINs， IPMNs and PDAC / 中华胰腺病杂志

ABSTRACT

ObjectiveTo detect the expressions of β-catenin protein in different pancreatic tissues ( NP,PanINs,IPMNs and PDAC) and evaluate its significance during the carcinogenesis of PDAC.Methods The expression of β-catenin protein in 12 samples of normal pancreatic tissues,52 samples of IPMN (IPMA 20 foci,IPMB 13 foci,IPMC 19 foci),PanINs 118 foci (PanIN-1 73 foci,PanIN-2 29 foci,PanIN-3 16 foci),50 cases of PDAC was determined by using immunohistochemistry. The correlation between β-catenin expression and clinicopathologic characteristics of PDAC was analyzed. Results β-catenin was mainly expressed in cell membrane of NP,the quantity was 4.38 ± 2.11 ; in PanINs,PDAC and IPMN,β-catenin membrane expression was significantly decreased or absent,the β-catenin membrane expressions of PanIN-1,PanIN-2,PanIN-3,PDAC,IPMA,IPMB,IPMC were 5.22 ±2.21,2.24 ±2.31,1.44 ±1.37,2.71 ±2.08,4.85 ±2.28,4.15 ±2.51,2.68 ±2.75.The cytoplasm expression of PanIN-1 was 12.3％ (9/73),while the nuclear expression was 0 ; and the corresponding values were 34.5％ (10/29) and 3.4％ ( 1/29 ) in PanIN-2; 43.8％ (7/16) and 12.5％ (2/16) in PanIN-3; 44.0％ (22/50) and 10.0％ (5/50) in PDAC.The IHCS of β-catenin membrane expression decreased with the severe tissue atypia along the progressive multistage.The β-catenin membrane expression was significantly associated with tumor size,neural infiltration and lymphatic metastasis ( P ＜ 0.05 ).Ectopic cytoplasm expression was significantly associated with tumor size (P＜0.05 ). Ectopicnuclear expression was significantly associated with tumor differentiation (P＜0.01).The membrane or ectopic cytoplasm expression of β-catenin was significantly associated with postoperative survival.ConclusionsAbnormal Wnt/β-catenin signal activation induces decreased β-catenin membrane expression and increased ectopic expression,which is an important mechanism of pathogenesis and development of PDAC,and promotes the growth and metastasis of PDAC.The expression of β-catenin was associated with postoperative survival.