Regulation of tissue factor expression by anti-oncogene PTEN in human neuroblastoma cell line

Objective To explore the role of PTEN gene in the regulation of tissue factor(TF)ex- pression in human neuroblastoma cells.Methods Expression of PTEN or TF was determined by Western blotting.Transcription of TF was examined by RT-PCR.PTEN gene expressing vector pCMV-PTEN was transfected with Lipofectamine2000.Phosphorylation of AKT was inhibited by LY294002 and then examined by Western blotting.Results Human neuroblastoma cell line SK-N-SH was PTEN-positive and expressed low level TF,whereas an other neuroblastoma cell line SK-N-MC was PTEN-negative but expressed high level TF.TF level was downregulated in SK-N-MC cells by enforced expression of PTEN in a dose dependent man- ner.Inhibition of TF was achieved along with inactivation of AKT.Furthermore treatment with PI3K/AKT in- hibitor LY294002 also resulted in decrease of TF expression in a dose-dependent manner.Conclusion Ex- pression of TF is inhibited by PTEN gene via inactivating PI3K/AKT pathway,loss of PTEN might be the ex- planation of abberant high-level TF in human neuroblastoma.It may be at least one of the mechanisms by which loss of PTEN expression confers to cancer progression.