ABSTRACT
Objective To verify the authors' previous cDNA micro-array results and to further investigate the moleculer mechanisms of gastric cancer. Methods Quantitative real-time RT-PCR was employed to detect the expressions of three S100A calcium-binding genes in 22 fresh surgical samples of gastric tumor tissue and non-cancerous mucosa from the same patients. Results The transcription level of S100A2 in primary cancer lesion was elevated in 80% of samples when compared with matching non-neoplastic mucosa (P=0.018) and the average up-regulation level was 10.78 fold. 55% of cancer lesions showed higher transcription level of S100A4 than their adjacent non-neoplastic mucosa, the average up-regulation level was 2.31 fold. S100A6 transcription level was higher in 74% (P=0.01) of primary cancer lesion with an 2.25 fold up-regulation than the adjacent non-neoplastic mucosa. After rectified by ?_2-microglobulin, the relative expression levels of S100A2, S100A4 and S100A6 were 2.83?10~ -4 , 6.44?10~ -2 and 0.41, respectively. According to the Spearman correlation coefficient analysis there were significant positive correlations between S100A2 and S100A4, and S100A2 and S1006 (P value were 0.00 and 0.017, respectively). Conclusion The changes in S100A2 and S100A6 genes may be an early event in a majority of gastric cancer patients, while S100A4 may be associated with the infiltration of gastric cancer. Further study on the three genes might be helpful for understanding the nature of gastric carcinoma.
ABSTRACT
Objective To study the expression of APE/Ref-1 in gastric cancer. Methods Detection of APE/Ref-1 protein was performed with gastric cancer tissue microarray (TMA) by IHC in gastric cancer, non-neoplastic mucosa and lymph node with metastasis. Results The positive rates of APE/Ref-1 in cytoblast in non-neoplastic mucosa, tumor tissue, and metastatic lymph nodes were 96.6%, 97.1% and 98.9%, respectively, while the positive rates in cytoplasm were 71.8%, 21.4% and 10.0%, respectively and in both cytoblast and cytoplasm were 71.4%, 21.4% and 10.0%, respectively. Compared to non-neoplastic mucosa, tumor lesion had lower APE/Ref-1 expression in cytoblast and cytoplasm. In 35.9% of patients it was decreased slightly and in 11.2% of them it was decreased markedly in cytoblast (P
ABSTRACT
Objective To study the expression of S100A4 in gastric cancer and normal gastric tissue, and analyze its correlation with the clinico-pathological features and prognosis of gastric cancer. Methods Real-time quantitative reverse transcription PCR (real time qRT-PCR) was used to detect the S100A4 expression in 20 fresh surgical samples of gastric cancer and normal gastric tissue as controls. The microarray of gastric cancer tissue was established for the analysis of the S100A4 expression immunohistochemically in 208 gastric cancer tissue and isogeneic normal gastric mucosa and lymph node with metastasis. Results The S100A4 expression was increased in 55% (11/20) of gastric cancer samples with an average of 2.31 fold up-regulation of that of the normal mucosa. Patients with lymph node metastasis showed a higher percentage of elevated S100A4 transcription than those without metastasis (P=0.024). As displayed by immunohistochemistry, the positive rate of S100A4 in non-neoplastic mucosa, primary tumor and lymph node with metastasis was 9.4%, 28.1% and 32.2%, respectively (P≤0.01). A higher percentage of elevated S100A4 expression was shown in patients in advanced stage than in patients in early stage (P=0.004). In primary tumor lesions, the S100A4 expression correlated significantly with the depth of invasion (P=0.003) and poorer prognosis (P=0.034). S100A4 expression in lymph node with metastasis was also associated with poor outcome (P=0.002). Multifactorial Cox's regression analysis showed that TNM stage (P=0.029) and the expression levels of S100A4 (P=0.024) in lymph node were independent influence factors for prognosis. Conclusions Expression of S100A4 may be a late event which is associated with the progression and prognosis of gastric cancer. The analysis of S100A4 expression in lymph-node metastasis is helpful in judging the prognosis of gastric cancer.