Objective       To design and synthesize siRNA sequences targeting androgen receptor (AR)

and to screen effective sequences by transfecting C4-2 cells.       Methods       Three pairs of siRNA sequences targeting AR were designed and synthesized according to the cDNA of AR

and were transfected into androgen-independent prostate carcinoma C4-2 cells to determine an optimal concentration. Experimental groups comprised of siRNAⅠ

siRNAⅡ

and siRNAⅢ

negative control

blank control and unrelated control. RT-PCR and Western blotting were applied to detect mRNA and protein expression of AR

respectively. Cell growth activity and the most effective siRNA sequence were evaluated based on cell growth curves by CCK-8 analysis.       Results       Cell growth activities of C4-2 cells transfected with different concentrations of AR siRNA (20 nmol/L

50 nmol/L

100 nmol/L and 200 nmol/L

respectively) were suppressed

and 100 nmol/L was the optimum concentration of AR siRNA (P0.05). Compared with those of the control groups

mRNA and protein levels of AR decreased significantly

and C4-2 cell growth activity was suppressed significantly in the groups of C4-2 cells transfected with AR siRNA (P0.05). The inhibitory effect of AR siRNAⅠ was the most significant than that of the others.       Conclusion       The newly designed AR siRNA can inhibit C4-2 cell proliferation by silencing AR expression.