[Effects of silent nucleostemin gene expression on apoptosis of HL-60 cells in vitro].

This study was aimed to explore whether the apoptosis of leukemia cells can be induced by targeting silencing nucleostemin gene in vitro. HL-60 cells were taken as the model, and were directly transfected with nucleostemin short hairpin RNA (NS-shRNA). Sequences unrelated with NS gene were taken as control. The blocking effect of NS-shRNA was detected by RT-PCR, the morphology changes in living cells were observed under inverted microscope, and the changes of cell shape and nucleus were detected by Wright-Giemsa staining. The amount of apoptotic cells were assayed by flow cytometer (FCM) and TUNEL technique, and the positive rate of apoptosis was determined meanwhile. The results showed that two NS-shRNA were synthesized in vitro, and the more effective one was selected to be transfected into HL-60 cells. The blocking rate of NS-mRNA reached to 74.94%. After transfection for 48 hours, Wright-Giemsa staining showed nuclear fragmentations and "apoptosis body" in cells. The apoptosis rate in transfected group detected by flow cytometry and TUNEL method were (25.32 +/- 3.06)% and (27.3 +/- 3.21)% respectively, but were only (3.12 +/- 0.38)% and (3.30 +/- 1.52)% in control group, the difference between the transfected group and the control group was significant (p < 0.01). It is concluded that the apoptosis of HL-60 leukemia cells can be induced by the silencing NS gene expression in vitro, which provides a theoretical basis for using NS gene as a candidate target gene in therapy of malignant tumor.