Nuclear expression of S100A4 is associated with lymph node metastasis in gastric carcinoma

OBJECTIVE: To investigate the intracellular localization of S100A4 in gastric carcinoma cells and the relationship between S100A4 expression status and lymph node metastasis of gastric carcinoma. METHODS: Western blotting analysis was performed to locate the expression of S100A4 protein in sub-fraction components of frozen tissues. S100A4 protein expression was also determined by immunohistochemical method in 131 samples of gastric cancer and 20 samples of matched metastatic lymph nodes. RESULTS: Thirty-two of 131 (24.4%) gastric carcinoma showed positive S100A4 nuclear expression and 50/131 (38.2%) carcinoma showed positive cytoplasmic expression. In 32 samples with positive S100A4 nuclear expression, 30 (93.8%) carcinomas had positive lymph node metastases. S100A4 nuclear expression level was higher in gastric carcinoma with lymph node metastasis (29.1%) than that without lymph node metastasis (7.1%) (P=0.016). CONCLUSION: Nuclear expression of S100A4 is associated with lymph node metastasis of gastric carcinoma.