[Study of FN1 and ZNF438 gene expression negatively regulated by androgen receptor in androgen-independent LNCaP cells].

Objective: To verify whether FN1 and ZNF438 are the androgen receptor(AR) target genes in LNCaP-AI cells and investigate the effects of AR exerts on FN1 and ZNF438 gene expression.
Methods: ChIP-PCR and agarose gel electrophoresis were performed to verify the fact that AR acted on FN1 and ZNF438 gene. Subsequently, LNCaP-AI cells were treated with dihydrotestosterone(DHT)and lentivirus transfection to down-regulate AR expression. The expression of FN1 and ZNF438 gene in mRNA and protein levels were analyzed by RT-qPCR and Western blot.
Results: FN1 and ZNF438 gene enrichment of AR-ChIP group were 7.274±0.290 and 6.843±0.078, significantly higher than the IgG-ChIP group of 1.004±0.113 and 1.000±0.014 (t(FN1)=34.91, t(ZNF438)=128.377, P<0.05). Differences were statistical significance. After DHT stimulation, the expression of FN1 and ZNF438 gene in mRNA and protein levels were 0.434±0.050 and 0.069±0.042, significantly lower than the control group of 1.000±0.016 and 1.025±0.277 (t(FN1)=18.532, t(ZNF438)=5.905, P<0.05). Differences were statistical significance. Moreover, after AR down-regulation, the expression of FN1 and ZNF438 gene in mRNA and protein levels were 17.579±4.415 and 1.895±0.424, significantly higher than the control group of 1.028±0.445 and 1.041±0.190 (t(FN1)=6.461, t(ZNF438)=3.184, P<0.05). Differences were statistical significance.
Conclusions: FN1 and ZNF438 gene are AR negatively regulated target genes in LNCaP-AI cells. The study might provide a new sight to further explore the mechanism of LNCaP-AI cells grow in androgen-depleted conditions.