Expression and clinical significance of BRCA1 in human esophageal squamous cell carcinoma

Objective To investigate the expression of BRCA1 in esophageal squamous cell carcinoma （ESCC） tissues and evaluate its correlation with clinicopathological features as well as the prognosis of ESCC patients. Methods The expression of BRCA1 was detected by immunohistochemistry （IHC） in 201 specimens of T3 stage ESCC tissues and corresponding adjacent normal tissues using tissue microarray. The correlation between BRCA1 expression and clinicopathological features of ESCC was determined by chi-square analysis. The cumulative survival rate was analyzed by Kaplan-Meier method. Results The positive rate of BRCA1 expression in ESCC tissues was significantly higher than that in adjacent normal tissues [ 88.6% （ 178/201 ） vs. 36.8% （74/201）, P 〈 0.001 ]. There was a significant correlation between the expression of BRCA1 and lymph node metastasis. In the tumors with positive lymph nodes, strong positive expression of BRCA1 was found in 45.0% （49/109） , while only 19.6% （18/92） in tumors without lymph node metastasis, showing a significant difference （ P 〈 0. 001 ）. A close relationship was also found between the expression of BRCA1 and gross typing of tumors （P 〈 0.05）. The expression of BRCA1 was not significantly correlated with gender, age, tumor location, differentiation, and tumor thrombus （ P 〉 0.05 ）. The results of Kaplan-Meier analysis indicated that ESCC patients with a higher positive rate of BRCA1 expression have a poorer prognosis （ P 〈 0.05 ）. Conclusions The expression of BRCA1 is related to the occurrence and development of esophageal carcinoma. BRCA1 protein may serve as a new potential biomarker in estimating the biological behavior of ESCC. Key words: Breast cancer susceptibility gene l;  Esophageal neoplasms;  Neoplasms, squamous cell ;  Lymph nodes ;  Neoplasms metastasis ;  Prognosis