Role of DJ-1-induced PTEN down-regulation in migration and invasion of human glioma cells

Abstract

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.