Of particular interest was periostin (POSTN), which was found to have a significantly higher expression in DDR2-expressing NOFs co-cultured with ES2 tumor cells (NOF siCTRL + ES2) compared to DDR2-depleted NOFs co-cultured with tumor cells (NOF siDDR2 + ES2) (Fold change = 2.0, p = 0.03) (Figure 2A). This evidence concerns the gene DDR2 and neoplasm.