Proliferation of Androgen-refractory Prostate Cancer Cells Disruption of Androgen Receptor Function Inhibits

Prostate cancer cells depend on androgens and the androgen receptor (AR) for survival. However, after androgen ablation therapy, tumors relapse to an androgen-refractory state. To determine whether the androgen receptor is critical for proliferation of androgen-refractory prostate cancer cells, we disrupted the activity of the androgen receptor with an antibody and an AR mRNA hammerhead ribozyme in the following cell lines: LNCaP (androgen-sensitive), LNCaP-Rf and LNCaP-C4 (androgenrefractory), and DU-145 (androgen-insensitive). Microinjection of either antibody or ribozyme inhibited proliferation of androgen-refractory cells. These findings demonstrate that the AR is critical for proliferation of androgen-refractory cells, even in the absence of androgens.