Effects of knocking-down nucleostemin gene on apoptosis of HL-60 cells in vitro

Objective. To explore whether the apoptosis of leukemia cells could be induced by knocking-down Nucleostemin (NS) gene in vitro. Methods. HL-60 cells were taken as a model, and was directly transfected with Nucleostemin specific short hairpin RNA (NS-shRNA). Sequences that unrelated with NS gene were taken as a control. The blocking effect of NS-shRNA was detected by Reverse Ttranscription PCR (RT-PCR), the morphology changes in culture state 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 in the meanwhile. Results. 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 up to 74.94%. 48 hours after transfection, nuclear fragmentations and " apoptosis bodies" showed in HL-60 cells, observed by Wright-Giemsa staining. The apoptosis rates in transfected groups 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, detected by FCM and Tunel technique. The difference between the treated group and the control group was significant (P< 0.01). Conclusion. The apoptosis of HL-60 leukemia cells can be induced by the silencing of NS gene in vitro, which means NS could be a candidate gene for the theoretical therapy principle of leukemia. [YUE Bao-hong, WANG Yuan-yuan, YU Li-na, FU Shu-zhen, ZHANG Qin-xian, KAN Quan-cheng. Effects of knocking-down Nucleostemin gene on apoptosis of HL-60 cells in vitro. Life Science Journal. 2011; 8(3): 290-294] (ISSN: 1097-8135). http://www.lifesciencesite.com.