Clinical significance of breast cancer anti-estrogen drug resistance protein 1 expression in serum and tissues of esophageal squamous cell cancer

Abstract

Objective To determine clinical significance of breast eancer anti-estrogen drug resistance protein 1 (BCAR1) expression in sera and tissues of esophageal squamous cell cancer (ESCC).Methods Between Feb.2010 and Jan.2011,serum BCAR1 levels in 46 cases of ESCC and 25 healthy volunteers from our department were detected by using enzyme linked immunosorbent assay (ELISA).A total of 106 ESCC samples and their adjacent normal tissues from our department obtained between Feb.2004 and July 2006 were investigated for BCAR1 protein expression by using tissue microassay (TMA) and immunohistochemistry (IHC).Results The serum BCAR1 levels were significantly higher in ESCC group than in normal control group (P ＜0.01 ).The serum BCAR1 levels in advanced ESCC group were significantly higher than in early ESCC group and normal control group ( P ＜ 0.01 ).The serum BCAR1 levels were decreased after removal of ESCC. BCAR1 protein was strongly expressed in 97％ of ESCC samples ( 103/106),while weekly expressed in 15％ of adjacent normal tissues (16/106) ( P ＜ 0.001 ).There was a significant correlation between BCAR1 positive expression and differentiation (P ＜0.05 ),however,there was no correlation between BCAR1 positive expression and age,gender,lymph node metastasis,depth of invasion and TNM stage ( P ＞ 0.05 ).Survival analysis revealed that BCAR1 low expression was in favor of survival time in comparison with BCAR1 high expression ( P ＜ 0.01 ). BCAR1 expression and lymph node metastasis were independent prognosis indictor by COX regression analysis.Conclusion BCAR1 protein expression is significantly higher in sera and tissues of ESCC than normal control group,and has a correlation with progression,therapeutic efficacy,differentiation and prognosis of ESCC.BCAR1 protein might be used as a new tumor marker for diagnosis and prognosis of ESCC. Key words: Breast cancer anti-estrogen drug resistance protein 1; Esophageal squamous cell carcinoma; Tissue microassay