Differential gene expression pattern in early gastric cancer by an integrative systematic approach

To elucidate the molecular basis of early gastric cancer (EGC), the genome-wideexpression pattern of cancer and normal tissues from 27 patients were analyzedby a microarray-based method. Using an integrative systematic bioinformatics approach,we classified the differentially expressed genes in EGC. Interestingly, the morehighly expressed genes in EGC exhibited the most significant correlation withcell migration and metastasis. This implies that, even at the early stage of gastriccancer, the molecular properties usually observed in late-stage cancer are alreadypresent. Furthermore, we have found a novel association between the expressionpattern and molecular pathways of EGC and estrogen receptor α (ERα)-negative breastcancer through cross-experimental analysis. These results provide new insightsinto the biological properties of EGC, as well as yielding useful basic data forthe study of molecular mechanisms of EGC carcinogenesis.