RESUMO
Objective To observe the effects and study the underlying mechanism of siRNA targeting PARP1 on the proliferation of androgen independent prostate cancer PC3 cell line.Methods Three specific siRNA sequences targeting PARP1 were designed and synthesized.And two sequences which had better interfering effect on the expression of PARP1 were evaluated and selected through lipofectamine transfection,RT-PCR and Western Blot.The effect of PARP1 silencing on the proliferation of PC3 cells was observed with MTS assay and the levels of the phosphorylation of Akt and GSK3β were detected by Western Blot.Results Compared to the blank control group,the transfected group with the negative control sequence had no significant impact on the expression of PARP1,however the transfected group with siRNA-1706,-2003 or-2907 could significantly suppress the mRNA and protein expression of PARP1.The mRNA inhibition rate reached to(52.07 ± 4.65)％,(44.38 ± 9.15)％ and(22.05 ± 6.65)％,respectively;and the protein inhibition rate reached to(86.86 ± 4.94)％,(83.30 ± 7.18)％ and(63.05 ± 10.19)％,respectively.The siRNA-1706 and-2003 could significantly inhibit the proliferation of PC3 cells;the inhibition rate was(38.93 ± 3.87)％ and(34.93 ± 1.21)％.And they also could down-regulate the intracellular levels of phosphorylated Akt and GSK3β in PC3 cells.Conclusion PARP1-targeted siRNA can significantly suppress the expression of endogenous PARP1 and inhibit the proliferation of PC3 cells,which is related to the inhibition of Akt activity and the activation of GSK3 β.
