[Effect of vascular endothelial growth factor antisense oligonucleotide on human leukemic cell line HL-60]

This study was aimed to investigate expression of vascular endothelial growth factor mRNA (VEGF mRNA) and its relationship with leukemic cell apoptosis after VEGF antisense oligonucleotide (VEGF ASODN) transferred into HL-60 cells. The phosphorothiate VEGF ODN was transferred into HL-60 cells in vitro by using cation poly mediated method, the inhibitory rate of cell proliferation was assayed by MTT, expression of VEGF mRNA was measured by RT-PCR, cell apoptosis was detected by cell morphology observation, DNA agarose gel electrophoresis and flow cytometer (FCM). The results showed that difference of the inhibitory rate of cell proliferation and the relative expression of VEGF mRNA between ASODN group and MSODN or control groups under the same condition (p < 0.05) was statistic significant, but no significant difference (p > 0.05) was found between MSODN and control. The number of clusters of cells in ASODN group decreased; the morphology features of apoptotic cells involved cell shrinking, more granulation in cytoplasm, nuclear contracting and many fragments of cells. In MSODN and control groups, however, cells were plump and clear, and grow healthly. The result of electrophoresis revealed DNA ladder in ASODN group, while only one band of DNA in control groups. The rate of cell apoptosis was 19.46% in ASODN group with a significant difference as compared with MSODN groups and control (p < 0.05). The rate of HL-60 cell apoptosis in combination of VEGF ASODN with VP16 was significantly higher than that in VP16 alone (p < 0.05) and showed time- and dose- dependence. It is concluded that VEGF ASODN can down-regulate expression of VEGF mRNA of HL-60 cells, induces the apoptosis, inhibits the proliferation of HL-60 cells and enhances VP16-induced apoptosis in HL-60 cells, the VEGF ASODN in combination with VP16 shows additive effect.