Evaluation of TAZ expression and its effect on tumor invasion and metastasis in human glioma

Objective: To evaluate the expression of TAZ and its role in tumor invasion and metastasis in human glioma. Methods: The expression of TAZ protein was measured in 48 samples of surgically resected human glioma and 13 samples of normal brain tissues using immunohistochemisny. TAZ was knocked down by a retrovirus mediated TAZ shRNA in a glioma cell line, SNB19. Transwell cell migration and invasion assays were used to determine migration and invasion of SNB19 cells. Results: The positive expression rate of TAZ protein in glioma tissues was significantly higher than that in normal brain tissues (79.2% vs. 15.4%, P<0.001). Furthermore, clinical analysis suggested that the positive expression rate of TAZ protein in poorly differentiated tumor tissues was significantly higher as compared with that in well differentiated tissues (96.0% vs. 60.9%, P<0.01). TAZ was significantly knocked down by TAZ shRNA (P<0.001), and TAZ knockdown significantly reduced cell migration and invasion (P<0.01, respectively) in SNB19 cells. Conclusions: TAZ protein overexpression is observed in human glioma and its elevated expression is significantly correlated with poor differentiation. TAZ knockdown prominently reduces cell migration and invasion in SNB19 cells, suggesting that TAZ may play a key role in the initiation and progression of human glioma.