Expression of Human Prostatic Acid Phosphatase Correlates with Androgen-stimulated Cell Proliferation in Prostate Cancer Cell Lines

Abstract

Androgen plays a critical role in regulating the growth and differentiation of normal prostate epithelia, as well as the initial growth of prostate cancer cells. Nevertheless, prostate carcinomas eventually become androgen-unresponsive, and the cancer is refractory to hormonal therapy. To gain insight into the mechanism involved in this hormone-refractory phenomenon, we have examined the potential role of the androgen receptor (AR) in that process. We have investigated the expression of AR and two prostate-specific androgen-responsive antigens, prostatic acid phosphatase (

Androgen signaling and post-transcriptional downregulation of Bcl-2 in androgen-unresponsive prostate cancer

“…LNCaP prostate cancer cells are androgen-responsive at low passage numbers but become androgen-unresponsive at high passage numbers. 11 Table 1 outlines the passage numbers and designations of the LNCaP cells used in this study.…”

c-Jun enhancement of androgen receptor transactivation is associated with prostate cancer cell proliferation

“…Additionally and perhaps more importantly, endogenous c-Jun is required for the proliferation of androgen-independent LNCaP cells. Utilizing LNCaP cells that were cultured to grow independent of androgens and thereby mimic the hormone-refractory stage of prostate cancer (Lin et al, 1998;Igawa et al, 2002), we have been able to block the growth of these cells, in either the absence or presence of androgens, by siRNA-mediated diminishing of endogenous c-Jun expression. As these cells exhibit c-Jun coactivation of AR-dependent transcription and we have evidence that their proliferation is dependent on AR-regulated gene expression (C Cai and L Shemshedini, unpublished results), it is likely that the proliferative role of endogenous c-Jun in androgen-independent LNCaP cells is mediated via its coactivation function on AR, irrespective of whether androgen is present or not.…”

“…c-Jun mediates the proliferation of androgen-independent LNCaP cells To determine the importance of c-Jun in androgenindependent LNCaP cells, we studied androgen-independent LNCaP cells that were established through continuous passage in culture (Lin et al, 1998;Igawa et al, 2002). These cells, C81, closely mimic hormonerefractory prostate cancer and thus proliferate in an androgen-unresponsive manner, whereas C33 are the parental androgen-dependent cells (Igawa et al, 2002).…”

Variations of Proline-Rich Kinase Pyk2 Expression Correlate with Prostate Cancer Progression

“…The role of testosterone in regulating the growth and differentiation of prostate cells is still unclear. Although testosterone is an essential factor for prostate gland development, it is not clear whether testosterone is a direct mitogen for prostate acinar cells (Griffiths et al, 1997;Lee et al, 1997;Lin et al, 1998;Ruijter et al, 1999).…”