Open AccessDual androgen‐response elements mediate androgen regulation of MMP‐2 expression in prostate cancer cells
Author(s) -
Li BenYi,
Liao XinBo,
Fujito Atsuya,
Thrasher J. Brantley,
Shen FangYun,
Xu PingYi
Publication year - 2007
Publication title -
asian journal of andrology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.701
H-Index - 74
eISSN - 1745-7262
pISSN - 1008-682X
DOI - 10.1111/j.1745-7262.2007.00226.x
Subject(s) - chromatin immunoprecipitation , androgen receptor , androgen , biology , promoter , microbiology and biotechnology , prostate cancer , electrophoretic mobility shift assay , bicalutamide , reporter gene , luciferase , transcription factor , gene expression , chemistry , cancer research , gene , endocrinology , transfection , genetics , cancer , hormone
Aim : To characterize the matrix metalloproteinases (MMP)‐2 promoter and to identify androgen response elements (AREs) involved in androgen‐induced MMP‐2 expression. Methods : MMP‐2 mRNA levels was determined by reverse transcription‐polymerase chain reaction (RT‐PCR). MMP‐2 promoter‐driven luciferase assays were used to determine the fragments responsible for androgen‐induced activity. Chromatin‐immunoprecipitation assay and electrophoretic mobility shift assays (EMSA) were used to verify the identified AREs in the MMP‐2 promoter. Results : Androgen significantly induced MMP‐2 expression at the mRNA level, which was blocked by the androgen antagonist bicalutamide. Deletion of a region encompassing base pairs ‐1591 to ‐1259 (relative to the start codon) of the MMP‐2 promoter led to a significant loss of androgen‐induced reporter activity. Additional deletion of the 5′‐region up to ‐562 bp further reduced the androgen‐induced MMP‐2 promoter activity. Sequence analysis of these two regions revealed two putative ARE motifs. Introducing mutations in the putative ARE motifs by site‐directed mutagenesis approach resulted in a dramatic loss of androgen‐induced MMP‐2 promoter activity, indicating that the putative ARE motifs are required for androgen‐stimulated MMP‐2 expression. Most importantly, the androgen receptor (AR) interacted with both motif‐containing promoter regions in vivo in a chromatin immunoprecipitation assay after androgen treatment. Furthermore, the AR specifically bound to the wild‐type but not mutated ARE motifs‐containing probes in an in vitro EMSA assay. Conclusion : Two ARE motifs were identified to be responsible for androgen‐induced MMP‐2 expression in prostate cancer cells. Edited by Prof. Chawnshang Chang