Bioactive Materials Key Lab of Ministry of Education, Department of Biochemistry and Molecular Biology, College of Life Sciences, Nankai University, Tianjin, China.
Prostate. 2010 Feb 15;70(3):317-32. doi: 10.1002/pros.21066.
Stromal smooth muscle cells (SMCs) play an important role in the pathogenesis and clinical symptom of benign prostatic hyperplasia. We had reported that estrogen enhances the phenotype of SMC in cultured prostate stromal cells (PRSCs). Here we further investigate the mechanism by which estrogen affects the differentiation of PRSCs.
Primary cultured PRSCs were stimulated with E2 or BSA-E2. The mRNA level of SMC-specific genes, smoothelin, and SM-MHC were measured by qRT-PCR. The SM-MHC protein was measured by Western blot. The mRNA and protein levels of TGF-beta1 were measured by qRT-PCR and ELISA. The MAPK inhibitor PD98059, the estrogen receptor antagonist ICI182,780 and neutralizing antibody to TGF-beta1 were used to reveal the mechanism of estrogen effect.
E2 and BSA-E2 significantly up-regulate the expression of SMC-specific genes in PRSCs. Both forms of estrogen could increase the expression of TGF-beta1, which can be blocked by pre-treating with PD98059. Moreover, PD98059 and TGF-beta1 neutralizing antibody could abrogate the effect of BSA-E2 on cell differentiation. However, they could only inhibit part of E2-induced SMC phenotype enhancement. ICI182,780 could partially suppress the pro-differentiation effect of E2 but had no influence on the effect of BSA-E2. Combined treatment with ICI182,780 and PD98059 can completely abrogate the effect of E2.
Estrogen could promote the expression of TGF-beta1 in PRSCs through nongenomic activation of MAPK pathway, and in turn enhance the SMC phenotype. Besides for this nongenomic effect, estrogen can also enhance the SMC phenotype through classical genomic action.
基质平滑肌细胞（SMCs）在良性前列腺增生的发病机制和临床症状中起重要作用。我们曾报道过雌激素增强培养的前列腺基质细胞（PRSCs）中 SMC 的表型。在这里，我们进一步研究了雌激素影响 PRSCs 分化的机制。
用 E2 或 BSA-E2 刺激原代培养的 PRSCs。通过 qRT-PCR 测量 SMC 特异性基因 smoothelin 和 SM-MHC 的 mRNA 水平。通过 Western blot 测量 SM-MHC 蛋白。通过 qRT-PCR 和 ELISA 测量 TGF-β1 的 mRNA 和蛋白水平。使用 MAPK 抑制剂 PD98059、雌激素受体拮抗剂 ICI182780 和 TGF-β1 中和抗体来揭示雌激素作用的机制。
E2 和 BSA-E2 显著上调 PRSCs 中 SMC 特异性基因的表达。两种形式的雌激素均可增加 TGF-β1 的表达，而 PD98059 预处理可阻断该表达。此外，PD98059 和 TGF-β1 中和抗体可消除 BSA-E2 对细胞分化的影响。然而，它们只能抑制部分 E2 诱导的 SMC 表型增强。ICI182780 可部分抑制 E2 的促分化作用，但对 BSA-E2 无影响。ICI182780 和 PD98059 的联合治疗可完全消除 E2 的作用。
雌激素可通过 MAPK 途径的非基因组激活促进 PRSCs 中 TGF-β1 的表达，并进而增强 SMC 表型。除了这种非基因组作用外，雌激素还可以通过经典的基因组作用增强 SMC 表型。
