Comparative proteomic analysis for the detection of biomarkers in pancreatic ductal adenocarcinomas

Abstract

Aims: To search for novel potential protein biomarkers for the early detection and better intervention of PDAC.

Methods: Eight pairs of matched PDAC and non-cancerous pancreas tissues were profiled with 2-DE, differentially expressed proteins were identified by MS. Expression patterns of TBX4 and HSP60 were studied with immunohistochemistry using tissue microarrays.

Results: A total of 48 differentially expressed proteins were identified, of them, 30 proteins were novel potential biomarkers. Immunohistochemistry showed that TBX4 expression could be seen in both centroacinar cells and small ducts in normal pancreas and tumor cells in 5/5(100%) well differentiated, 35/38(92.1%) moderately differentiated, and 11/18(61.1%) poorly differentiated PDAC tissues with different staining intensity, however, in normal acinar cells and tumor cells in the other 3/38(7.9%) moderately differentiated and 7/18(38.9%) poorly differentiated PDAC tissues, there was no visible TBX4 expression, the expression difference of TBX4 between moderately differentiated and poorly differentiated PDAC tissues was found to be statistically significant (P <0.01). In addition, there was obvious morphology difference between TBX4 negatively stained and positively stained tumor cells which suggest different celluar origins. Strong expression of HSP60 could be seen in both acinar cells and small ducts in normal pancreas tissues and tumor cells in PDAC tissues except for islets and tumor stoma and no correlation was found between HSP60 expression and differentiation of PDAC tissues.

Conclusions: We identified 30 novel potential biomarkers differentially expressed in PDAC tissues and found that TBX4 may be a differentiation related protein, its prognostic value for PDAC deserve further study.