CD44 and metastatic malignant neoplasm: Immunohistochemical (IHC) analysis was used to detect the expression of candidate stem cell markers Oct4, Sox2, Gli1, CD44, CD133, and potential stemness-related signaling pathway molecules p-AKT and p-ERK in samples from 101 primary lesions of gastric cancer and 72 distant metastatic cancer tissues, of which 21 gastric cancer primary lesions and their paired distant metastasis tissues were included.