[Overexpression of PTEN gene inhibits proliferation of bladder transitional carcinoma cell line EJ]

To evaluate the anticancer effects of exogenous human WT-PTEN overexpression on bladder transitional carcinoma cell line EJ.

The plasmid containing WT-PTEN or mutant PTEN was separately transfected into bladder transitional carcinoma cell line EJ, and the protein expression of PTEN in the EJ cells was detected by Western blot. Cell morphological changes were observed under the inverted microscope and transmission electron microscope. MTT test was used to assess the effect of PTEN on proliferation and anticancer effects for mitomycin and theraubicin. The change of bcl-2 expression in the cells was measured by Western blot. The empty plasmid was used as control.

Western blot analysis showed that EJ cells expressed high level of PTEN protein after transfection with WT-PTEN or mutant PTEN plasmid. Abnormal morphological changes of the cells were observed in WT-PTEN transfected groups. The growth of EJ cells treated with WT-PTEN was significantly inhibited by 40.1% and anticancer effects were enhanced by mitomycin and theraubicin, but the cells transfected with mutant PTEN plasmid did not show such similar biological behavior.

WT-PTEN gene transfection can suppress the in vitro growth and induce apoptosis of bladder transitional carcinoma cell line EJ cells. Mutant PTEN does not show similar biological behavior. Overexpression of WT-PTEN inhibits cancer cell proliferation by down-regulating bcl-2 expression in the cells.