ABSTRACT
BACKGROUND:Tumor stem cels not only initiate tumorigenesis, but also are involved in the invasion and metastasis of tumor cels. For tumor stem cels, to identify the specific cel surface marker has become a research hotspot. OBJECTIVE:To explore the clinical significance of cancer stem cel surface marker CD44 in gastric cancer invasion and lymph node metastasis. METHODS: CD44 protein expression in specimens of gastric cancer tissue was detected by the immunohistochemical SABC method. The relationship between CD44 protein expression and biological characteristics and prognosis of gastric cancer was detected using Pearsonχ2 test and Cox regression analysis. RESULTS AND CONCLUSION:Among 100 cases of gastric carcinoma, 59 cases (59%) were positive for CD44 protein expression. CD44 protein expression in normal gastric mucosa at above 5 cm from the edge of primary gastric cancer was negative. CD44 protein was widely expressed in tissues of gastric cancer, mainly expressed in the cel membrane, and a smal amount of expression in the cytoplasm. CD44 protein expression in gastric cancer tissue was not correlated with sex of the patients or age (P > 0.05), but was associated with tumor staging and lymph duct tissue infiltration, histological grade, and tumor size (P < 0.05). Deep tumor invasion, high histological grade, big diameter of tumor, and lymph node metastasis could lead to high positive CD44 protein expression. Positive expression of CD44 is an independent prognostic factor affecting postoperative survival (P < 0.05). The results show that the cancer stem cel surface markers CD44 in gastric carcinoma tissues is strongly associated with invasion of gastric carcinoma and lymph node metastasis. High expression of CD44 presents poor prognosis.