Annexin A2 expression in human esophageal squamous cell carcinoma and correlation with invasion and metastasis

Abstract

Objective To explore Annexin A2 expression in human esophageal squamous cell carcinoma (ESCC) and investigate the correlation of Annexin A2 expression with invasion and metastasis of human ESCC. Methods From 2000 to 2008, specimens of Xinjiang medical University First Affiliated Hospital were collected. Pathologically confirmed ESCC surgical specimens were set as experimental group, and the corresponding tumor adjacent tissues located more than 5 cm far from ESCC center were set as control group. 22 fresh and 175 paraffin-embeded ESCC specimens with corresponding adjacent tissues were randomly collected as study samples. With qRT-PCR, Western-blot and immunohistochemistry, the expression of Annexin A2 were detected at the mRNA and protein level. The correlation between Annexin A2 expression and clinicopathological parameters was analyzed. Results In 22 pairs of fresh ESCC and corresponding tumor adjacent tissues, the expression of Annexin A2 at mRNA level was significantly higher in tumor adjacent tissues (0. 06 ± 0. 06) than that in ESCC (0. 02 ±0. 02) (P＜0.05 ). Annexin A2 expression at protein level was also significantly higher in tumor adjacent tissues (0.95±0. 42) than ESCC (0.81±0. 36) (P＜0.05). In 175 paraffin-embeded ESCC specimens and corresponding adjacent tissues, the positive rate of Annexin A2 protein expression was 82. 3% (144/175) of the ESCC samples, which was lower than corresponding tumor adjacent tissues 92. 0% (161/175)(P＜0. 05). In addition, Annexin A2 expression was correlated with lymphoid node metastasis (P＜0.05) and pathological differentiation in patients with ESCC (P＜0.05). However, there was no apparent correlation with gross type (P＞0. 05). Conclusion The low expression of Annexin A2 in ESCC maybe played a potential role in the carcinogenesis, invasion and metastasis. Key words: Esophageal neoplasms; Neoplasms, squamous cell; Annexin A2; Neoplasms invasion; Neoplasms metastasis