Over-expressed Fas improves the apoptosis of malignant T-cells in vitro and vivo.

Fas play a critical role in T-cell apoptosis by functioning as a major cell-surface death receptor. To explore a potential method that can improve the sensitivity to Fas-mediated apoptosis in malignant precursor T-cells. Fas gene was stable transfected into Jurkat cells to establish a new cell line named Jurkat-Fas with over-expressed Fas. RT-PCR, real-time RT-PCR, flow cytometry, and confocal microscopy assay were performed to detect the Fas level of mRNA and protein in the two cell lines. The sensitivities to Fas-mediated apoptosis of the two cell lines were evaluated by flow cytometry with Alexa Fluor 488 annexin V/PI staining in vitro. Tumor xenograft models were prepared with Jurkat and Jurkat-Fas cells for in vivo study. Fas mRNA and protein levels in Jurkat-Fas cell line were higher than that in Jurkat cell line. Compared to Jurkat cells, apoptosis rates of Jurkat-Fas cells were remarkably higher in vitro, and the tumor growth of Jurkat-Fas cells in nude mice was significantly inhibited in vivo. Stable over-expression of extrinsic Fas gene can significantly ameliorate the sensitivity to Fas-mediated apoptosis in human malignant T-cell, which indicates a novel strategy to improve therapeutic effects on precursor T-cell malignancy.