Abstract:

Objective    To explore the effect of lentiviral vector-mediated siRNA on c-myc gene expression in Jiyoye cells by using the RNAi technique in vitro. Methods     Three interference sequences c-myc-1, c-myc-2 and c-myc-3 and the negative control c-myc-neg that targeted human c-myc mRNA were designed and synthesized. After annealing, all the fragments were cloned into the pLVX vector，which were transfected into human leukemia Jiyoye cells by lentivirus and were cultured for 72 hours. The cells were divided into five groups: the blank control group(untransfected), the c-myc-neg group, the c-myc-1 group, the c-myc-2 group and the c-myc-3 group. After 72 hours, the transfection rate in each group was determined by flow cytometry. Expressions of the c-myc mRNA and c-Myc protein were detected by Real-time PCR and Western blot. Results    PLVX-c-myc-neg, PLVX-c-myc-1, PLVX-c-myc-2 and PLVX-c-myc-3 were constructed. C-myc mRNA and protein expression levels in the three groups respectively transfected with c-myc-1, c-myc-2 and c-myc-3 were significantly down-regulated -compared with the negative control group transfected with c-myc neg(P<0.05). The c-myc-3 group decreased most significantly compared with the c-myc-1 group and the c-myc-2 group (P<0.05). There was no significant difference between the untransfected group and the negative control group (P>0.05). Conclusion     The successfully constructed shRNA expression vector for the cmyc gene suppresses expression of cmyc in Jiyoye cells, which might provide an experimental basis for further study of the role of cmyc gene silencing in targeting treatment of leukemia and lymphoma.

Key words: Genes, myc; Small interfering RNA; Small hairpin RNA; Jiyoye cells；RNA interference