Prolonged androgen deprivation leads to downregulation of androgen receptor and prostate-specific membrane antigen in prostate cancer cells

Abstract

Emergence of androgen-independent cancer cells during androgen deprivation therapy presents a significant challenge to successful treatment outcomes in prostate cancer. Elucidating the role of androgen deprivation in the transition from an androgen-dependent to an androgen-independent state may enable the development of more effective therapeutic strategies against prostate cancer. Herein, we describe an in vitro model for assessing the effects of continuous androgen-deprivation on prostate cancer cells (LNCaP) with respect to the expression of two prostate-specific markers: the androgen receptor (AR) and prostate-specific membrane antigen (PSMA). Compared with androgen-containing normal growth medium, androgen-deprived medium apparently induced the concomitant downregulation of AR and PSMA over time. Decreased protein levels were confirmed by fluorescence imaging, western blotting and enzymatic activity studies. In contrast to the current understanding of AR and PSMA in prostate cancer progression, our data demonstrated that androgen-deprivation induced a decrease in AR and PSMA levels in androgen-sensitive LNCaP cells, which may be associated with the development of more aggressive disease-state following androgen deprivation therapy.