Purpose: The aim of this study was to identify proteins associated with gastric cancer lymph node metastasis and explore the clinicopathological significance of these proteins.
Methods: Gastric cancer tissues were obtained from 24 patients with high or low lymph node metastatic potential. Total cellular proteins were separated by two-dimensional gel electrophoresis (2-DE), analyzed by MALDI/TOF-TOF MS, and identified by a database search. Expression of 14-3-3β and profilin-1 was then immunohistochemically verified in paraffin-embedded gastric cancer tissues from 128 patients and analyzed by multivariate logistic regression models, Kaplan-Meier curves, and Cox proportional hazard models.
Results: A total of 26 differentially expressed proteins were identified, 20 of which were overexpressed and 6 of which were underexpressed. 14-3-3β and profilin-1 were upregulated in gastric cancer tissues with and without lymph node metastasis, respectively. Expression of 14-3-3β protein was associated, but profilin-1 expression was inversely associated with gastric cancer lymph node metastasis. Multivariate analysis showed that overexpression of 14-3-3β and reduced expression of profilin-1 were independent risk factors for gastric cancer lymph node metastasis, while 14-3-3β overexpression was an independent prognostic factor for gastric cancer patients.
Conclusions: The current study identified 26 differentially expressed proteins. Further studies showed that both 14-3-3β and profilin-1 protein may be useful biomarkers for prediction of gastric cancer lymph node metastasis and that expression of 14-3-3β was a prognostic marker for gastric cancer patients.