Alteration of PTEN gene expression affects the migration of human airway smooth muscle cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in human airway smooth muscle cell (HASMC) migration and related signaling pathway after interference with PTEN gene expression.</p><p><b>METHOD</b>HASMCs were infected with an adenovirus vector and RNA interference vector of human PTEN gene to establish the cell model with PTEN gene over-expression (Ad-GFP-PTEN-HASMC) and one with PTEN gene silencing (Ad-shPTEN-HASMC), using Ad-GFP-infected and a blank cells as the negative controls and LY294002 as the positive control. Fluorescence microscopy and flow cytometric analysis were used to evaluate the transfection efficiency, and Western blotting was performed to examine the expression of PTEN and the activation of AKT and ERK1/2 signal pathway. Transwell assay and wound healing assay were used to assess the migration of HASMCs.</p><p><b>RESULTS</b>The adenovirus over-expression vector and RNA interference vector significantly affected the expression of human PTEN gene. Up-regulation of PTEN gene resulted in a slow-down of the HASMC migration, an inhibition of PI3K/AKT signal pathway at the protein level but no changes in Ras-Raf-MEK1/2-ERK1/2 signal pathway. Down-regulated PTEN gene expression, however, was not associated with an enhancement of HASMC migration, but activated PI3K/AKT signal pathway and inhibited Ras-Raf-MEK1/2-ERK1/2 signal pathway.</p><p><b>CONCLUSION</b>Upregulation of PTEN gene can effectively inhibit airway smooth muscle cell migration, the effect of which is probably mediated by the PI3K/AKT pathway.</p>

Effect of recombinant adenovirus carrying PTEN gene on the proliferation of human airway smooth muscle cells in vitro and the mechanisms / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effect of exogenous phophatase and tensin homolog deleted on chromosone 10 (PTEN) gene transfer via recombinant adenoviruses on the proliferation of human airway smooth muscle cells (HASMCs) in vitro and investigate the possible mechanisms.</p><p><b>METHODS</b>With a recombinant adenovirus vector containing PTEN (Ad-PTEN) constructed using the pAdxsi system, PTEN gene was transiently transfected into HASMCs and the transfection efficiency was determined by fluorescence microscope. RT-PCR and Western blotting were performed to detect the expression of PTEN mRNA and protein in the infected cells. MTS/PMS assay was used to analyze the proliferation of HASMCs, and the cell cycle changes of the transfected cells were evaluated by flow cytometry with PI staining. The expression levels of Akt and p-A kt proteins were detected by Western blotting, and P21 mRNA expression determined by RT-PCR.</p><p><b>RESULTS</b>The recombinant adenovirus Ad-PTEN showed a wild-type PTEN gene transfer efficiency of 98% at the multiplicity of infection (MOI) of 100. RT-PCR and Western blotting showed that infection with the recombinant adenovirus resulted in PTEN overexpression in the HASMCs, causing also increased ratio of G(0)/G(1) cells and proliferation inhibition of the ASMCs. The overexpression of PTEN significantly decreased the expression level of p-Akt but increased P21 mRNA expression.</p><p><b>CONCLUSION</b>The recombinant adenovirus containing PTEN can be successfully transfected into HASMCs cultured in vitro, resulting in PTEN overexpression at both the mRNA and protein levels. PTEN overexpression can efficiently inhibit the proliferation of HASMCs possibly through the PI3K/PKB/AKt and P21 pathways.</p>