[Effect of PML(NLS-) gene mediated by recobinant adenovirus vector on emodin-induced apoptosis of HL-60 cells].

ABSTRACT

OBJECTIVE: To determine the effect and mechanism of action of PML(NLS-) gene on emodin-induced apoptosis of human HL-60 cells. METHODS: HL-60 cells were infected with recombinant adenovirus Ad-PML (NLS-) and Ad-KZ, respectively. The PML(NLS-) gene was detected by Real-time PCR(RT-PCR) and Western blot. The proliferation level of the HL-60 cells was determined by MTT method. The HL-60 cells were treated with 60 micromol/L emodin for 72 h and then analyzed by flow cytometry for their cell cycle and apoptosis rate. The transcription levels of apoptosis-related BCL-2, BAX and C-MYC genes were determined by RT-PCR. The translation levels of those genes were determined by Western blot. RESULTS: Compared with normal controls and the HL-60 cells infected with Ad-KZ, the mRNA and protein expression levels of PML(NLS-) gene increased significantly in the HL-60 cells infected with Ad-PML( NLS-). Increased proliferation levels of the Ad-PML (NLS-) infected HL-60 cells were observed in those treated with 60 pmol/L emodin, which showed decreased percentage of cells at Gx phase, increased percentage of cells at S phase, and decreased emodin-induced apoptosis. The levels of mRNA transcription and protein expression of BAX gene decreased, while those of BCL-2 and C-MYC genes increased significantly. CONCLUSION: The over-expression of PML(NLS-) gene might promote the proliferation and arrest the apoptosis of HL-60 cells by up-regulating the expressions of BCL-2 and C-MYC genes and down-regulating the expression of BAX gene.