RESUMEN
BACKGROUND & OBJECTIVE: Our recent study on proteomics for esophageal cancer has indicated the importance of Annexin II as a promising protein to distinguish esophageal cancer patients from healthy subjects. This study was to detect the expression of Annexin II in esophageal squamous cell carcinoma (ESCC) and adjacent tissues, and to explore the role of Annexin II in ESCC pathogenesis and mechanisms. METHODS: The expression of Annexin I in 33 specimens of ESCC and adjacent tissues from Linzhou, a high-incidence area for esophageal cancer in Henan province, was detected by ABC immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Annexin II protein was expressed in 90.6% normal esophageal epithelium and decreased with ESCC progression. In carcinoma in situ (CIS), 50.0% foci lost Annexin II protein expression. The expression of Annexin II protein was increased in well differentiated SCC and decreased with loss of differentiation of SCC. In poorly differentiated SCC, 45.4% foci lost Annexin II protein expression. However, RT-PCR did not detect differential expression of Annexin II mRNA between normal esophageal epithelium and CIS. CONCLUSIONS: Elevated or reduced expression of Annexin II may be correlated to reverse or progression of carcinogenesis respectively, and Annexin II may be another candidate biomarker for screening of high-risk subjects and early diagnosis of SCC.