Bcl-2 and androgen receptor gene expression in androgen-independent subclone derived from mouse androgen-dependent cells.
We investigated bcl-2 and androgen receptor (AR) expression in an androgen-independent subline derived from mouse androgen-dependent mammary carcinoma cells. The androgen-independent SCAI cells were subcloned by cultivating androgen-dependent SC2G cells in serum-free, androgen-free conditions. The growth of the SCAI cells was not affected by testosterone. Western blot analysis showed greater expression of Bcl-2 protein in SCAI cells than in SC2G cells. A four-day culture with 4 microM antisense oligonucleotide complementary to mouse bcl-2 significantly decreased the viability of SCAI cells, when compared with sense control. The amount of the AR-mRNA expression in SCAI cells was slightly weaker. Direct sequence analysis showed no mutations in the AR of either androgen-dependent or -independent cells. These data indicate that the increased expression of Bcl-2 protein plays an important role in acquiring tolerance for the testosterone ablation, although it is not related to AR gene alteration.
Department of Urology, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. ohigashi@sc.itc.keio.ac.jp
Takashi
T
Ohigashi
Munehisa
M
Ueno
Shoichi
S
Nonaka
Nobuhiro
N
Deguchi
Masaru
M
Murai
D000728:Androgens / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000235:genetics*; D015153:Blotting, Western; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D019254:Genes, bcl-2 / Q000235:genetics*; D015674:Mammary Neoplasms, Animal / Q000503:physiopathology*; D051379:Mice; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis; D011944:Receptors, Androgen / Q000096:biosynthesis / Q000235:genetics*; D013739:Testosterone / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D000728:Androgens; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D011944:Receptors, Androgen; D013739:Testosterone