Expression pattern of the identified genes
To investigate whether the different experimental groups could be classified with significant genes, an unsupervised hierarchical clustering method was applied to the significant gene set (Fig. 2).
The normal group consisted of 4 tissues and showed significantly lower expression levels when compared with the tumor group. In Fig. 2, we investigated the classification availability of the identified genes in Data 2004, not in a combined dataset, because the two datasets have different expression scales.