Background and Objective: DJ-1, a suppressor of PTEN, promotes metastasis of different tumors, but its function and mechanisms in glioma metastasis remain unclear. This study aimed to investigate the effect of the DJ-1 protein on the migration and invasion of human glioma cells, and to explore potential mechanisms. Methods: The eukaryotic expression vector pEGFP/DJ-1 and small interfering RNA (siRNA) were constructed and transfected into human glioma SWO-38 cells. The expression of DJ-1 and PTEN in SWO-38 cells were detected by Western blot. Cell migration and invasion were detected by transwell assay. Results: After transfection of pEGFP/DJ-1, the expression of DJ-1 (1.28 ± 0.15 vs. 0.89 ± 0.04, P < 0.05) and focal adhesion kinase (FAK) phosphorylation (0.76 ± 0.12 vs. 0.51 ± 0.04, P < 0.05) were increased, whereas the expression of PTEN (0.74 ± 0.2 vs. 1.04 ± 0.14, P < 0.05) was suppressed. After transfection of DJ-1 siRNA, both DJ-1 (0.33 ± 0.04 vs. 0.88 ± 0.06, P < 0.05) and p-FAK levels (0.33 ± 0.01 vs. 0.44 ± 0.05, P < 0.05) were decreased, but PTEN expression (1.1 ± 0.06 vs. 0.81 ± 0.12, P < 0.05) was increased. Transwell assay data showed that pEGFP/DJ-1 transfection promoted SWO-38 cell migration (57.2 ± 6.50 vs. 40.4 ± 5.0, P < 0.05) and invasion (54.6 ± 4.9 vs. 27 ± 6.7, P < 0.05), whereas DJ-1 siRNA transfection inhibited SWO-38 cells migration (54.4 ± 6.9 vs. 73.4 ± 7.6, P < 0.05) and invasion (44.6 ± 5.8 vs. 69.2 ± 9.2, P < 0.05). Conclusion: Over-expression of DJ-1 promotes SWO-38 cell migration and invasion possibly through the DJ-1 and the PTEN/FAK pathway.
Mao Fang Xue-Yun Zhong Bin Du Chen-Li Lin Feng Luo Li-Juan Tang Juan Chen
The tumor stem cell theory supposed that tumor stem cells are the origin of tumor abnormal proliferation,invasion,metastasis,drug resistance and recurrence.As the theory is put forward,it redefines the functions of classic stem cells in tumorigenesis.It is a great event for recent studies on glioma initiating cells as brain tumor stem cells were identified and isolated successfully.A lot of evidence from experiments in vivo and in vitro demonstrates that brain tumor stem cells might play an important role in glioma tumorigenesis.In this review,we discuss the relationship between tumor stem cells and tumorigenesis,and the research on the correlation between brain tumor stem cells and glioma genesis.
