Laboratory of Clinical and Experimental Pathophysiology, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.
Int J Oncol. 2010 Mar;36(3):553-62. doi: 10.3892/ijo_00000529.
We investigated the effects of testosterone and the pure anti-androgen, bicalutamide, on DNA synthesis and cell cycle in androgen-sensitive or -insensitive human and mouse cell lines by 3H-thymidine incorporation, flow cytometry, RT-PCR and Western blotting. In androgen-dependent mouse SC-3 cells, testosterone induced DNA synthesis, shift of cell cycle distribution from G0/G1 to S/G2/M and expression of cyclin A. The induction was preceded by that of fibroblast growth factor 8 (FGF-8), and completely blocked by monoclonal antibody to FGF-8. Dihydrotestosterone (DHT) induced cyclin A expression in androgen-sensitive human prostate cancer cells, but not in androgen-independent cell lines. Bicalutamide almost completely inhibited these androgen-dependent effects both in LNCaP and SC-3 cells, but had no or limited effect on androgen-independent or FGF-8-induced DNA synthesis, and FGF-8 induced cyclin A expression. Interestingly, bicalutamide inhibited both DNA synthesis and the cyclin A expression in androgen-independent human cell lines in serum-free condition. A MEK1/2 inhibitor U0126 blocked both androgen- and rFGF-8-induced DNA synthesis. Overall, bicalutamide inhibits the cyclin A expression possibly by inhibiting FGF-8 mRNA expression and FGF-8 protein secretion but not by inhibiting FGF receptor (FGFR) signalling in androgen-dependent cell lines, and by other mechanisms in androgen-independent cell lines. The results suggest that combination with compounds such as FGFR signalling inhibitors may provide additional benefits to anti-androgens. It is also suggested that cyclin A could be a sensitive marker for androgen-induced cancer growth and for the growth inhibitory effects of anti-androgen.
我们通过 3H-胸腺嘧啶掺入、流式细胞术、RT-PCR 和 Western blot 研究了睾酮和纯抗雄激素比卡鲁胺对雄激素敏感或不敏感的人源和鼠源细胞系中 DNA 合成和细胞周期的影响。在雄激素依赖性的小鼠 SC-3 细胞中，睾酮诱导 DNA 合成，细胞周期从 G0/G1 期向 S/G2/M 期转移，并诱导细胞周期蛋白 A 的表达。这种诱导先于成纤维细胞生长因子 8（FGF-8）的诱导，且可被 FGF-8 的单克隆抗体完全阻断。二氢睾酮（DHT）可诱导雄激素敏感的人前列腺癌细胞中细胞周期蛋白 A 的表达，但不能诱导雄激素非依赖性细胞系的表达。比卡鲁胺几乎完全抑制 LNCaP 和 SC-3 细胞中这些依赖雄激素的作用，但对雄激素非依赖性或 FGF-8 诱导的 DNA 合成以及 FGF-8 诱导的细胞周期蛋白 A 表达无影响或影响有限。有趣的是，在无血清条件下，比卡鲁胺抑制雄激素非依赖性人源细胞系中的 DNA 合成和细胞周期蛋白 A 的表达。MEK1/2 抑制剂 U0126 阻断了雄激素和 rFGF-8 诱导的 DNA 合成。总的来说，比卡鲁胺通过抑制 FGF-8 mRNA 表达和 FGF-8 蛋白分泌抑制依赖雄激素的细胞系中细胞周期蛋白 A 的表达，而不是通过抑制 FGF 受体（FGFR）信号，在雄激素非依赖性细胞系中通过其他机制抑制细胞周期蛋白 A 的表达。这些结果表明，与 FGFR 信号抑制剂等化合物联合应用可能会为抗雄激素提供额外的益处。此外，细胞周期蛋白 A 可能是雄激素诱导的癌症生长和抗雄激素的生长抑制作用的敏感标志物。
