Immunohistochemical staining of DEK protein in gastric cancer and normal mucosa. A: DEK is negative in normal gastric mucosa. B: DEK protein is strongly positive in the nucleus of gastric cancer cells with lymph node metastasis. C: DEK protein showed scattered staining pattern in gastric adenocarcinoma without metastasis. D: DEK is positive in invasive cancer cells around the nerve (arrow) in the serosal layer (Original magnification, ×200).