Krishnan Aruna V, Shinghal Rajesh, Raghavachari Nalini, Brooks James D, Peehl Donna M, Feldman David
Department of Medicine, Stanford University School of Medicine, Stanford, California 94305-5103, USA.
Prostate. 2004 May 15;59(3):243-51. doi: 10.1002/pros.20006.
1,25-dihydroxyvitamin D(3) [1,25(OH)2D3] exerts growth inhibitory, pro-differentiating, and pro-apoptotic effects on prostate cells. To better understand the molecular mechanisms underlying these actions, we employed cDNA microarrays to study 1,25(OH)2D3-regulated gene expression in the LNCaP human prostate cancer cells.
mRNA isolated from LNCaP cells treated with vehicle or 50 nM 1,25(OH)2D3 for various lengths of time were hybridized to microarrays carrying approximately 23,000 genes. Some of the putative target genes revealed by the microarray analysis were verified by real-time PCR assays.
1,25(OH)2D3 most substantially increased the expression of the insulin-like growth factor binding protein-3 (IGFBP-3) gene. Our analysis also revealed several novel 1,25(OH)2D3-responsive genes. Interestingly, some of the key genes regulated by 1,25(OH)2D3 are also androgen-responsive genes. 1,25(OH)2D3 also down-regulated genes that mediate androgen catabolism.
The putative 1,25(OH)2D3 target genes appear to be involved in a variety of cellular functions including growth regulation, differentiation, membrane transport, cell-cell and cell-matrix interactions, DNA repair, and inhibition of metastasis. The up-regulation of IGFBP-3 gene has been shown to be crucial in 1,25(OH)2D3-mediated inhibition of LNCaP cell growth. 1,25(OH)2D3 regulation of androgen-responsive genes as well as genes involved in androgen catabolism suggests that there are interactions between 1,25(OH)2D3 and androgen signaling pathways in LNCaP cells. Further studies on the role of these genes and others in mediating the anti-cancer effects of 1,25(OH)2D3 may lead to better approaches to the prevention and treatment of prostate cancer.
1,25 - 二羟基维生素D(3)[1,25(OH)2D3]对前列腺细胞具有生长抑制、促分化和促凋亡作用。为了更好地理解这些作用背后的分子机制，我们采用cDNA微阵列研究了1,25(OH)2D3对LNCaP人前列腺癌细胞中基因表达的调控。
从用载体或50 nM 1,25(OH)2D3处理不同时间长度的LNCaP细胞中分离出的mRNA与携带约23,000个基因的微阵列进行杂交。通过实时PCR分析验证了微阵列分析揭示的一些假定靶基因。
1,25(OH)2D3最显著地增加了胰岛素样生长因子结合蛋白-3(IGFBP - 3)基因的表达。我们的分析还揭示了几个新的1,25(OH)2D3反应性基因。有趣的是，一些受1,25(OH)2D3调控的关键基因也是雄激素反应性基因。1,25(OH)2D3还下调了介导雄激素分解代谢的基因。
假定的1,25(OH)2D3靶基因似乎参与多种细胞功能，包括生长调节、分化、膜转运、细胞间和细胞与基质相互作用、DNA修复以及转移抑制。IGFBP - 3基因的上调已被证明在1,25(OH)2D3介导的LNCaP细胞生长抑制中至关重要。1,25(OH)2D3对雄激素反应性基因以及参与雄激素分解代谢的基因的调控表明，LNCaP细胞中1,25(OH)2D3和雄激素信号通路之间存在相互作用。对这些基因及其他基因在介导1,25(OH)2D3抗癌作用中的作用进行进一步研究，可能会带来更好的前列腺癌预防和治疗方法。
