University of Southern California/Norris Comprehensive Cancer Center, Keck School of Medicine, Los Angeles, CA 90033, USA.
Prostate. 2011 Jun 1;71(8):892-8. doi: 10.1002/pros.21305. Epub 2010 Nov 17.
Recent data has shown that prostate cancer (PCA) cells are capable of producing testosterone directly from cholesterol, which may contribute to the development of castration resistance. While up-regulation of steroidogenic enzymes has been previously described during castration-resistant prostate cancer (CRPC) progression, regulation of this process is poorly defined. These data examine the role of luteinizing hormone (LH) in the regulation of steroidogenic machinery in PCA cells.
PCA cell lines LNCaP, C4-2B, and 22RV1 were exposed to LH. Gene expression was quantified using real-time PCR and protein expression was characterized with standard Western blot analysis. Steroid analysis was performed using radioimmunoassay (RIA). Cell viability was measured using an MTS viability assay.
Androgen-sensitive (LNCaP) and -independent PCA cells (C4-2B and 22RV1) express both mRNA and protein for LH and LH receptor (LHR). Exposure of these cells to LH for 4 hr increased the expression of several steroidogenic genes. Exposure for 10 days resulted in the increase of additional genes. At both time points, the upregulation of these genes was dose-dependent. This was mirrored by an increase in the expression of several key steroidogenic enzymes, including StAR, CYB5B, CYP11A, and 3βHSD. LH stimulated the production of progesterone and testosterone in LNCaP cells as measured by RIA. We have also demonstrated that treatment of LNCaP cells with LH enhanced their viability.
Our data show that LH-mediated activation of LHR significantly up-regulates the expression of genes and enzymes required for steroidogenesis and increases steroid production in PCA cells.
最近的数据表明，前列腺癌 (PCA) 细胞能够直接从胆固醇中产生睾酮，这可能有助于去势抵抗的发展。虽然在去势抵抗性前列腺癌 (CRPC) 进展过程中已经描述了甾体生成酶的上调，但对这一过程的调控知之甚少。这些数据研究了促黄体生成素 (LH) 在调节 PCA 细胞甾体生成机制中的作用。
将 PCA 细胞系 LNCaP、C4-2B 和 22RV1 暴露于 LH 中。使用实时 PCR 定量基因表达，并用标准 Western blot 分析来描述蛋白表达。使用放射免疫测定 (RIA) 进行类固醇分析。使用 MTS 活力测定法测量细胞活力。
雄激素敏感 (LNCaP) 和非依赖雄激素的 PCA 细胞 (C4-2B 和 22RV1) 均表达 LH 和 LH 受体 (LHR) 的 mRNA 和蛋白。将这些细胞暴露于 LH 4 小时可增加几种甾体生成基因的表达。暴露 10 天可导致更多基因的增加。在这两个时间点，这些基因的上调都是剂量依赖性的。这与几种关键甾体生成酶（包括 StAR、CYB5B、CYP11A 和 3βHSD）的表达增加相吻合。LH 通过 RIA 刺激 LNCaP 细胞产生孕激素和睾酮。我们还证明，用 LH 处理 LNCaP 细胞可增强其活力。
我们的数据表明，LH 介导的 LHR 激活显著上调了甾体生成所需的基因和酶的表达，并增加了 PCA 细胞中的类固醇生成。
