Expression of CD44 according to Clinicopathologic Characteristics of Gastric Cancer / 이화의대지

OBJECTIVES: Cancer stem cells are defined as focal cluster of cells within a tumor that possess the capacity for self-renewal and differentiation into phenotypically heterogeneous cells. Cluster of differentiation 44 (CD44) is considered one of the gastric cancer stem cell markers. We aimed to investigate how the expression of CD44 varies according to the clinicopathologic characteristics in gastric cancer. METHODS: For this study, 157 patients who received an operation due to gastric cancer between May 1998 and December 2009 were selected. CD44 immunohistochemistry was reviewed using the semi-quantitative scoring of intensity and proportion. The sum of the intensity and proportion scores was calculated, and a score of 2 or less was deemed ‘CD44-negative’ and 3 or more as ‘CD44-positive.’ RESULTS: Among the final 143 subjects, 69 (48.3%) were CD44 positive. Older age, intestinal type gastric cancer, lymphatic invasion, and lymph node metastasis were significantly correlated with expression of CD44. In the multivariate analysis, older age was the only independent factor associated with CD44 expression (P=0.028). CD44 expression was correlated with overall survival, 5-year survival, and disease-free survival. In the multivariate analysis, older age, male gender, and lymphatic invasion were independent predictors of poor overall survival. Also, older age and lymphatic invasion were significant factors in 5-year survival, and lymphatic invasion was an independent factor of poor disease-free survival. CONCLUSION: Older age (≥60 years) was independently associated with CD44 expression in gastric cancer patients. Also, CD44 expression was correlated with poor prognosis in gastric cancer patients.

CD44 expression in patients with combined hepatocellular cholangiocarcinoma

PURPOSE: Combined hepatocellular cholangiocarcinoma (ChC) is a rare type of primary liver cancer, which is thought to have a poorer prognosis than hepatocellular carcinoma (HCC). Cancer stem cells are associated with tumorigenesis, tumor progression, recurrence, metastasis, and poor prognosis in several malignancies including HCC. The aim of this study was to investigate the expression pattern of cancer stem cell markers in ChC and HCC, and to evaluate whether this pattern correlated to patient prognosis. METHODS: Thirteen patients who underwent curative hepatic resection for ChC and 13 patients who underwent curative hepatic resection for HCC (matched control cases) were included. Immunohistochemical staining for cancer stem cell markers (cytokeratin [CK]7, CK19, C-kit, cluster of differentiation [CD] 44, CD133, and epithelial cell adhesion molecule) was performed and clinical outcomes were analyzed retrospectively. RESULTS: There was no significant difference in cancer stem cell marker expression between ChC and HCC. In ChC, the group that expressed CD44 showed earlier recurrence than the group that did not express CD44 (P = 0.040). CONCLUSION: The expression of cancer stem cell markers in ChC did not show a different pattern compared to that found in HCC. The expression of cancer stem cell marker CD44 was associated with poor prognosis in patients with ChC.