Objective      To investigate the inhibitory effect of wild-type phosphatase and tensin homolog deleted on chromosome ten (PTEN) gene on the growth and invasion of human glioblastoma cell line U251.       Methods      Recombinant plasmid pEGFP-PTEN containing wild-type PTEN gene segment was transferred into U251 cells by liposome transfection technique

and the transfection was identified by Western blotting. Cell growth was analyzed by MTT assay

and cell cycle and apoptosis were examined by flow cytometry. The protein levels of matrix metalloproteinase-2 (MMP-2)

matrix metalloproteinase-9 (MMP-9)

tissue inhibitor of met

alloproteinase-1 (TIMP-1) and tissue inhibitor of metalloproteinase-2 (TIMP-2) were detected by immunohistochemical method.       Results      The recombinant plasmid pEGFP-PTEN was successfully transferred into U251 cells

and PTEN protein expression was detected. Compared with those of the control group and empty vector group

the rate of cell growth inhibition decreased to 52.46%. The cell cycle was arrested at G

1

/S phase. The expression levels of MMP-2 and MMP-9 decreased significantly in the transfection group

while those of TIMP-1 and TIMP-2 significantly increased and were negatively correlated with the expression levels of MMP-2 and MMP-9 (r=-0.506

P0.05).        Conclusion      PTEN gene transfection can inhibit the growth of human glioblastoma U251 cell line

induce cell apoptosis

and inhibit cell invasion by downregulating MMPs and upregulating TIMPs.