Microarray analysis reveals potential target genes of NF-kappaB2/p52 in LNCaP prostate cancer cells

Our previous studies showed that NF-kappaB2/p52 is involved in the castration-resistant growth of the androgen-sensitive LNCaP prostate cancer cells. The role of NF-kappaB2/p52 in lymphomagenesis has been studied extensively, but its target genes in other cancers remain unknown. In order to identify genes potentially regulated by p52 in prostate cancer cells, we performed a genome-wide microarray analysis of genes differentially up- or down-regulated by the overexpression of p52 by adenoviral-mediated gene delivery in LNCaP cells.

Total RNAs from vector control-infected and Adeno-p52-infected LNCaP cells were used to prepare cDNAs, which were hybridized to the Whole Genome Human 44k Microarray chips (Agilent Technologies). Data analysis was performed using GeneSpring and Ingenuity Pathway Analysis software. Validation of microarray results was performed by real-time quantitative RT-PCR and Western blot analyses.

Expression of approximately 130 genes was differentially upregulated by >5-fold, whereas approximately 60 genes were differentially downregulated by >2-fold in p52-expressing LNCaP cells. Pathway analysis revealed that the upregulated genes belong to functional categories like cell growth and proliferation, cellular movement, cell-to-cell signaling and interaction, cancer, cell cycle, etc., whereas the downregulated genes were represented by functional categories like cell movement, antigen presentation, and cell death. Six of the top upregulated genes including annexin A2, PLAU, RND3, Twist2, VEGFC, and CXCL1 were validated by real-time PCR and Western blot analysis.

This study provides a comprehensive analysis of genes potentially regulated by NF-kappaB2/p52 in the LNCaP prostate cancer cell line and provides a rationale for the induction of castration-resistant growth by p52 in LNCaP cells.