Wnt信号通路靶基因GS mRNA及蛋白在胃癌中的表达

Expression and biological role of DKK1 in human esophageal cancer

AIM: To investigate the expression of dikkopf-1 (DKK1) in esophageal carcinoma tissue and four esophageal carcinoma cell lines and to explore the impact of DKK1 overexpression on cell cycle and invasion in EC9706 cell line.

METHODS: The expression of DKK1 in esophageal carcinoma tissues was detected by immunohistochemistry, and the distribution of DKK1 in esophageal carcinoma cell line TE13 was observed by immunofluorescence. Western blot was used to investigate the expression of DKK1 in esophageal carcinoma tissues and matched normal esophageal tissues, as well as in four esophageal carcinoma cell lines. A eukaryotic expression vector of DKK1 was constructed and transfected into EC9706 cells to evaluate the impact of DKK1 overexpression on cell cycle by flow cytometry and on cell invasion by Boyden chamber assay.

RESULTS: DKK1 was highly expressed in esophageal carcinoma tissues and mainly distributed in the cytoplasm of TE13 cells. The expression of DKK1 protein in carcinoma was obviously higher than that in matched normal esophageal tissue. Differential expression of DKK1 was observed in four esophageal carcinoma cell lines. Overexpression of DKK1 in EC9706 cells decreased the percentage of cells in G0/G1 phase and increased the percentage of cells in sphase and the number of cells penetrating through the membrane of Boyden chamber (252 ± 6.71 vs 99.18 ± 3.02; 252 ± 6.71 vs 112.33 ± 3.21, all P < 0.01).

CONCLUSION: DKK1 is overexpressed in esophageal carcinoma. Overexpression of DKK1 in EC9706 cells remarkably promoted cell invasion and progression from G1 phase to S phase.