Three isoforms of annexin I are preferentially expressed in normal esophageal epithelia but down-regulated in XXXX .

@entity1 @entity5 @entity189 @entity1721 @entity418
The development and progression of @entity1 @entity5 are believed to be due to the alterations of multiple genes or/and their protein products. For identifying the proteins associated with @entity418 , we analysed the protein profiles of 24 pairs of @entity1721 /matched adjacent normal epithelia. Microdissection of routinely unstained frozen sections was performed to purify cancerous and epithelial cells. The protein expression profiles were obtained by two-dimensional electrophoresis. Selected proteins dysregulated in @entity5 were identified by MALDI-TOF-MS. Three isoforms of annexin I were detected in normal esophageal mucosa and down-regulated in @entity1721 . RT-PCR analysis showed annexin I mRNA levels were significantly reduced in 17 out of 24 @entity189 . Immunohistochemistry demonstrated that annexin I appeared strong positive in all normal epithelia layers except basal cells. In @entity5 tissues, decreased expression of annexin I was observed in 12 out of 16 well differentiated @entity5 , 16 out of 17 moderately differentiated @entity5 , and 3 out of 3 poorly differentiated @entity5 as compared with the corresponding normal esophageal epithelia. There was a significant correlation between annexin I expression and the status of @entity5 differentiation. Well differentiated @entity5 presented stronger immunohistochemical reaction than moderately and poorly differentiated @entity5 . These data suggested that there existed three different isoforms of annexin I in normal esophageal epithelia, which may be the results of post-translational modification. Down-expression of three annexin I isoforms was a frequent event in esophageal carcinogenesis.
