Androgen Stimulates Matrix Metalloproteinase-2 Expression in Human Prostate Cancer

Xinbo Liao, J. Brantley Thrasher, Jill Pelling, Jeffery Holzbeierlein, Qing-Xiang Amy Sang, Benyi Li
2003 Endocrinology  
Prostate growth and differentiation is androgen dependent, and increased expression of matrix metalloproteinase 2 (MMP-2) has been found in more aggressive prostate cancers. As part of our efforts to elucidate the mechanisms responsible for prostate cancer progression, we evaluated the MMP-2 expression after androgen stimulation in human prostate cancer LNCaP and LAPC-4 cells, which express a functional androgen receptor. Treatment of the cells with a synthetic androgen R1881 resulted in an
more » ... ease of pro-MMP-2 expression assessed by Western blot and gelatinolytic zymography in both cell lines. R1881-stimulated pro-MMP-2 expression occurred in a dose-dependent manner, which was completely abrogated in the presence of the nonsteroid androgen antagonist bicalutamide. In accordance with the protein expression, MMP-2 promoter activity was also increased by R1881 in a cell-based luciferase reporter assay. However, R1881 treatment did not significantly affect either the pro-MMP-9 expres-sion or its promoter activity. Although we observed an appearance of active form of MMP-2, its activator MT1-MMP was not changed after R1881 treatment. Pretreatment of the cells with inhibitors of RNA transcription, actinomycin D, or protein translation, cycloheximide, significantly suppressed R1881-induced pro-MMP-2 expression in LNCaP cells, indicating that androgen stimulates pro-MMP-2 gene expression. In addition, phosphatidylinositol 3-kinase inhibitor, LY294002 or wortmannin, strongly inhibited R1881-induced pro-MMP-2 expression. Finally, R1881-enhanced LNCaP cell migration was clearly suppressed by LY294002 or the MMP-2 inhibitor OA-Hy in an in vitro migration assay. In conclusion, our data demonstrated that androgen stimulates pro-MMP-2 expression in LNCaP cells via phosphatidylinositol 3-kinasedependent androgen receptor transactivation. (Endocrinology 144: 1656 -1663, 2003) P ROSTATE CANCER IS the second most frequently diagnosed cancer in men after skin cancer in the United States and is second only to lung and bronchus cancer in the frequency of mortality (1). Since the seminal work of Huggins and Hodges in 1941 (2), it has been widely accepted that prostate growth and differentiation is androgen dependent. As a result of this insight, medical treatment for metastatic prostate cancer has relied heavily on androgen ablation. However, most patients treated by androgen ablation ultimately relapse to more aggressive androgen-refractory prostate cancer with no means to cure (reviewed in Ref. 3). The matrix metalloproteinase (MMP) family is comprised of secreted and membrane-associated zinc-dependent endopeptidases that can selectively degrade extracellular matrix (ECM) protein and nonmatrix proteins. Currently, up to 25 members of the MMP family have been reported, and the broad range of their substrates conveys a pivotal role for the MMP involvement in normal physiological processes and pathological states including tumor metastasis and angiogenesis (reviewed in Ref. 4). MMP-2, also called gelatinase A, is produced as a latent form (pro-MMP-2), and the activation process is mediated at least partially by MT1-MMP on the cell surface (5). It has been shown that MMP-2 is secreted by the human prostate gland, both in vivo and in vitro, and higher expression levels of MMP-2 are associated with increasing Gleason score, tumor metastasis, and aggressive behavior of prostate cancer (Refs. 6 and 7 and reviewed in Ref. 8). To understand the role of the androgen receptors (ARs) in prostate cancer development and progression, it is important first to determine the AR signaling cascades and the genes that are regulated by AR. In view of the evidence for the association of MMP-2 expression and prostate cancer behavior, we evaluated the expression of pro-MMP-2 after androgen treatment in human prostate cancer LNCaP and LAPC-4 cells, which express a functional AR. Materials and Methods Cell culture and reagents
doi:10.1210/en.2002-0157 pmid:12697668 fatcat:m2harqlu2bc7zp5jkbjwx37ywy