Identification of androgen-regulated genes in the prostate cancer cell line LNCaP by serial analysis of gene expression and proteomic analysis

A common therapy for nonorgan-confined prostate cancer involves androgen de privation. To develop a better understanding of the effect of androgen on p rostatic cells, we have analyzed gene expression changes induced by dihydro testosterone (DHT) in the androgen responsive prostate cancer line LNCaP, a t both RNA and protein levels. Changes at the RNA level induced by DHT were determined by means of serial analysis of gene expression (SAGE), and prot ein profiling was done by means of quantitative two-dimensional polyacrylam ide gel electrophoresis. Among 123371 transcripts analyzed, a total of 2884 4 distinct SAGE tags were identified representing 16570 genes. Some 351 gen es were significantly affected by DHT treatment at the RNA level (p < 0.05) , of which 147 were induced and 204 repressed by androgen. In two independe nt experiments, the integrated intensity of 32 protein spots increased and 12 decreased at least two-fold in response to androgen, out of a total of 1 031 protein spots analyzed. The change in intensity for most of the affecte d proteins identified could not be predicted based on the level of their co rresponding RNA. Our study provides a global assessment of genes regulated by DHT and suggests a need for profiling at both RNA and protein levels for a comprehensive evaluation of patterns of gene expression.