[Screening of differentially expressed proteins from human esophageal cancer and esophageal tissues by two-dimensional difference gel electrophoresis and mass spectrometry].

OBJECTIVE

To establish two-dimensional electrophoresis profiles from human esophageal cancer tissue and paired normal esophageal tissue and identify differentially expressed proteins to identify the molecular markers for early-stage diagnosis.

METHODS

The total proteins of human esophageal cancer tissue and paired normal esophageal tissue were separated by immobilized pH gradient-based two-dimensional gel electrophoresis (2-DE). The 6 differentially expressed proteins were analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The peptide mass fingerprintings (PMF) were identified by database searching. Six differentially expressed proteins were validated by RT-PCR.

RESULTS

The well-resolved, reproducible 2-DE patterns of esophageal cancer tissue and esophageal normal tissue were established. Using MALDI-TOF-MS technology, 6 differential protein spots were identified. Among them, the expressions of squamous cell carcinoma antigen 1 (SCCA1b), KRT4 and annexin A1 were downregulated and triosephosphate isomerase (TPI1), heat shock protein 27 (HSP27) and manganese superoxide dismutase (MnSOD) were upregulated in esophageal cancer tissues.

CONCLUSION

The identification of differential expressed proteins in human esophageal cancer and normal tissue will be helpful for screening the biomarker for early-stage diagnosis.