Objective To investigate the effect of interleukin-6(IL-6)on the human growth hormone(hGH)gene expression in a rat somatotropic pituitary cell line MtT/S.Methods The plasmids containing various lengths of hGH gene 5&#...Objective To investigate the effect of interleukin-6(IL-6)on the human growth hormone(hGH)gene expression in a rat somatotropic pituitary cell line MtT/S.Methods The plasmids containing various lengths of hGH gene 5'-promoter fragments were constructed.Stably transfected MtT/S cells were created by cotransfecting the above plasmids and pcDNA3.1(+)with DMRIE-C transfection reagent.After the administration of these cells with IL-6 and/or various inhibitors of signaling transduction pathways,the luciferase activities in MtT/S cells lysis were assayed to demonstrate the effects of IL-6 on hGH gene promoter activity and possibly involved mechanism.Results The 103 U/mL IL-6 stimulated GH secretion and synthesis,and promoted the 5'-promoter activity of GH gene in stably transfected MtT/SGL cells with the action of 1.69 times above the control.Among inhibitors of signaling transduction pathways,mitogen-activated protein kinase kinase(MAPKK/MEK)inhibitor PD98059(40 μmol/L)and p38 mitogen-activated protein kinase(MAPK)inhibitor SB203580(5 μmol/L)completely blocked the stimulatory effect of IL-6.Western blot analysis further confirmed the activation of phosphorylated MEK and p38 MAPK in MtT/SGL cells.Neither over-expression of Pit-1 nor inhibition of Pit-1 expression affected IL-6 induction of hGH promoter activity.A series of deletion constructs of hGH promoter were created to identify the DNA sequence that mediated the effect of IL-6.The results showed that the stimulatory effect of IL-6 was abolished following deletion of the-196 to-132 bp fragment.Conclusions IL-6 promotes GH secretion and synthesis by rat MtT/S somatotroph cells.The stimulatory effect of IL-6 on hGH gene promoter appears to require the activation of MEK and p38 MAPK,and a fragment of promoter sequence that spans the-196 to-132 bp of the gene,but may be unlinked with Pit-1 protein.展开更多
生长停滞特异性蛋白6(growth arrest specific protein 6,GAS6)在肿瘤发生发展中发挥重要作用,其信号转导参与细胞增殖、黏附与迁移,但它在子宫内膜异位症(endometriosis, EMs)的相关功能及分子机制尚不明确。本研究从GEO数据库检索并...生长停滞特异性蛋白6(growth arrest specific protein 6,GAS6)在肿瘤发生发展中发挥重要作用,其信号转导参与细胞增殖、黏附与迁移,但它在子宫内膜异位症(endometriosis, EMs)的相关功能及分子机制尚不明确。本研究从GEO数据库检索并下载子宫内膜异位症相关转录物组数据集,并对其进行GEO在线分析,筛选差异表达基因并进行GO聚类和KEGG通路富集分析。利用10例无内异症且无明确疾病妇女的在位子宫内膜,以及11例卵巢巧克力囊肿病人异位子宫内膜,对3个以上数据集共有的差异基因的mRNA水平进行实时荧光定量PCR验证。在子宫内膜异位症临床样本中,采用免疫组化、实时荧光定量PCR验证关键调控因子GAS6及上皮间充质转化(epithelial mesenchymal transition, EMT)标记基因的表达水平,并利用免疫荧光对GAS6和E-钙黏着蛋白(E-cadherin)进行共标。研究发现:从4个转录物组数据集中共筛选出47个差异表达基因,其主要富集于细胞迁移等过程以及MAPK、PI3K-AKT、紧密连接等相关信号通路。3个以上数据集所共有的9个差异基因在子宫内膜异位症病人中的mRNA水平均符合生物信息学分析的结果。GAS6在子宫内膜异位症病人异位内膜中的表达水平高于对照组(P<0.05),并且子宫内膜异位症病人的内膜组织中存在EMT现象,EMT的标志物E-钙黏着蛋白表达水平下调(P<0.05)、波形蛋白(vimentin)表达水平上调(P<0.01)。在GAS6高表达的子宫内膜异位症患者异位子宫内膜腺上皮细胞中,E-cadherin显示低表达,提示GAS6可能在子宫内膜异位症中介导EMT过程。综上所述,本研究初步揭示GAS6在子宫内膜异位症病人中高表达,及其可能介导EMT过程参与子宫内膜异位症的发生与发展,为子宫内膜异位症的临床治疗提供潜在靶标。展开更多
文摘Objective To investigate the effect of interleukin-6(IL-6)on the human growth hormone(hGH)gene expression in a rat somatotropic pituitary cell line MtT/S.Methods The plasmids containing various lengths of hGH gene 5'-promoter fragments were constructed.Stably transfected MtT/S cells were created by cotransfecting the above plasmids and pcDNA3.1(+)with DMRIE-C transfection reagent.After the administration of these cells with IL-6 and/or various inhibitors of signaling transduction pathways,the luciferase activities in MtT/S cells lysis were assayed to demonstrate the effects of IL-6 on hGH gene promoter activity and possibly involved mechanism.Results The 103 U/mL IL-6 stimulated GH secretion and synthesis,and promoted the 5'-promoter activity of GH gene in stably transfected MtT/SGL cells with the action of 1.69 times above the control.Among inhibitors of signaling transduction pathways,mitogen-activated protein kinase kinase(MAPKK/MEK)inhibitor PD98059(40 μmol/L)and p38 mitogen-activated protein kinase(MAPK)inhibitor SB203580(5 μmol/L)completely blocked the stimulatory effect of IL-6.Western blot analysis further confirmed the activation of phosphorylated MEK and p38 MAPK in MtT/SGL cells.Neither over-expression of Pit-1 nor inhibition of Pit-1 expression affected IL-6 induction of hGH promoter activity.A series of deletion constructs of hGH promoter were created to identify the DNA sequence that mediated the effect of IL-6.The results showed that the stimulatory effect of IL-6 was abolished following deletion of the-196 to-132 bp fragment.Conclusions IL-6 promotes GH secretion and synthesis by rat MtT/S somatotroph cells.The stimulatory effect of IL-6 on hGH gene promoter appears to require the activation of MEK and p38 MAPK,and a fragment of promoter sequence that spans the-196 to-132 bp of the gene,but may be unlinked with Pit-1 protein.
文摘生长停滞特异性蛋白6(growth arrest specific protein 6,GAS6)在肿瘤发生发展中发挥重要作用,其信号转导参与细胞增殖、黏附与迁移,但它在子宫内膜异位症(endometriosis, EMs)的相关功能及分子机制尚不明确。本研究从GEO数据库检索并下载子宫内膜异位症相关转录物组数据集,并对其进行GEO在线分析,筛选差异表达基因并进行GO聚类和KEGG通路富集分析。利用10例无内异症且无明确疾病妇女的在位子宫内膜,以及11例卵巢巧克力囊肿病人异位子宫内膜,对3个以上数据集共有的差异基因的mRNA水平进行实时荧光定量PCR验证。在子宫内膜异位症临床样本中,采用免疫组化、实时荧光定量PCR验证关键调控因子GAS6及上皮间充质转化(epithelial mesenchymal transition, EMT)标记基因的表达水平,并利用免疫荧光对GAS6和E-钙黏着蛋白(E-cadherin)进行共标。研究发现:从4个转录物组数据集中共筛选出47个差异表达基因,其主要富集于细胞迁移等过程以及MAPK、PI3K-AKT、紧密连接等相关信号通路。3个以上数据集所共有的9个差异基因在子宫内膜异位症病人中的mRNA水平均符合生物信息学分析的结果。GAS6在子宫内膜异位症病人异位内膜中的表达水平高于对照组(P<0.05),并且子宫内膜异位症病人的内膜组织中存在EMT现象,EMT的标志物E-钙黏着蛋白表达水平下调(P<0.05)、波形蛋白(vimentin)表达水平上调(P<0.01)。在GAS6高表达的子宫内膜异位症患者异位子宫内膜腺上皮细胞中,E-cadherin显示低表达,提示GAS6可能在子宫内膜异位症中介导EMT过程。综上所述,本研究初步揭示GAS6在子宫内膜异位症病人中高表达,及其可能介导EMT过程参与子宫内膜异位症的发生与发展,为子宫内膜异位症的临床治疗提供潜在靶标。
