EGFR expression status associated with lymph node ratio

We have tried to identify molecules associated with lymph node ratio expression by microarray. Expression microarray data prioritized gene candidates according to average expression ratio and its frequency. Among these genes, we examined particular EGFR expression by immunohistochemistry (IHC) in 167 advanced gastric cancer. We compared tumor specimens with high LNR (n=4) with those with low one (n=4) at mRNA level by Affymetrix microarray (harboring 54,675 genes) in stage III gastric cancer. We then prioritized the expression data, and enriched genes correlated with LNR, and finally validated EGFR as such candidates in primary advanced gastric cancer who underwent standard treatment (n=167).