Expression of three S100A calcium-binding proteins in human gastric cancer and non-cancerous mucosa as detected by QRT-PCR / 解放军医学杂志

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.