Association of β-catenin expression with clinicopathological characteristics and prognosis of patients with pancreatic ductal adenocarcinoma / 肿瘤研究与临床

ABSTRACT

Objective:To investigate the expression level of β-catenin and its relationship with clinicopathology and prognosis of patients with pancreatic ductal adenocarcinoma (PDAC).Methods:Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression of β-catenin mRNA in primary pancreatic cancer cell line and pancreatic ductal epithelial cell line HPDE6-C7 of the healthy. The data of 45 patients with PDAC confirmed by pathology at Xinjiang Medical University Cancer Hospital from June 2012 to December 2013 were retrospectively analyzed. Immunohistochemical method was used to detect the expression level of β-catenin in cancer tissues and adjacent tissues, and the correlation of β-catenin with pathological characteristics of patients with PDAC was analyzed. Cox proportional hazard model was performed to make univariate and multivariate analysis on the influencing factors of overall survival (OS).Results:The relative expression of β-catenin mRNA in primary pancreatic cancer cells was higher than that in HPDE6-C7 cell line [(3.83±0.83) vs. (1.00±0.03)], and the difference was statistically significant ( t = 3.45, P = 0.003). The high expression rate of β-catenin protein in PDAC tissues was higher than that in para-cancer tissues [68.9% (31/45) vs. 28.9% (14/45)], and the difference was statistically significant ( χ2 = 7.50, P = 0.005). The high expression rate of β-catenin protein in PDAC patients with different tumor diameter and TNM staging had statistically significant differences ( P = 0.026, P = 0.036). The median OS time of 45 patients was 22.5 months, and that of high expression of β-catenin protein group in 31 patients was 19 months, that of low expression of β-catenin group in 14 patients was 29 months, and the difference was statistically significant ( P = 0.009). Univariate Cox analysis showed that preoperative carbohydrate antigen199 (CA199) level, tumor diameter, tumor differentiation degree and the expression level of β-catenin protein were influencing factors of OS of patients with PDAC. Multivariate Cox analysis showed that preoperative CA199 ( OR = 9.883, 95% CI 2.815-34.689, P < 0.001), tumor diameter ( OR = 6.117, 95% CI 1.578-24.179, P = 0.009), tumor differentiation degree ( OR = 3.834, 95% CI 1.158-12.697, P = 0.028), the expression level of β-catenin protein ( OR = 0.139, 95% CI 0.045-0.430, P = 0.001) were independent affecting factors of OS of patients with PADC. Conclusions:β-catenin is abnormally highly expressed in PDAC which is correlated with the disease progression of patients and may be a new indicator and therapeutic target of prognosis for PDAC patients.