[Expression of PTEN gene in human glioma cell lines U251 and SHG-44 and its effect on cell proliferation].

Background & Objective: Mutation or deletion of PTEN gene is related to a variety of tumors. PTEN gene abnormality is closely related to the tumorigenesis of glioma. This study aimed to investigate the expression of PTEN gene in human glioma cell lines U251 and SHG-44, and explore its effect on cell proliferation.
Methods: The expression of PTEN gene in U251 and SHG-44 cells was detected by reverse transcription-polymerase chain reaction (RT-PCR). The recombinant eukaryotic expression vector containing wild-type PTEN gene was transfected into U251 and SHG-44 cells by cation polymex. The stably transfected cells were selected by G418 and amplified. Cell morphology was observed under microscope. The effect of PTEN gene on cell proliferation was assessed. The expression of PTEN protein and glial fibrillary acidic protein (GFAP) were detected by Western blot and immunohistochemistry.
Results: Point mutation and deletion of PTEN mRNA were observed respectively in U251 and SHG-44 cells. The proliferation rates of U251 and SHG-44 cells were inhibited by 39.1% and 27.8% of control at 7 days after transfection. The expression of PTEN and GFAP were both increased. The stably transfected U251 cells differentiated toward astrocytes, but SHG-44 cells had no obvious morphologic changes.
Conclusion: Restoring expression of wild-type PTEN could induce differentiation of glioma cells differently.