We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly ...We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.展开更多
Background Aberrant epithelial repair has been observed in chronic rhinosinusitis （CRS） patients; however, the mechanism of epithelial cell repair regulation is unclear. Epidermal growth factor （EGF） plays an impo...Background Aberrant epithelial repair has been observed in chronic rhinosinusitis （CRS） patients; however, the mechanism of epithelial cell repair regulation is unclear. Epidermal growth factor （EGF） plays an important role in regulating epithelial cell repair in lower airway and may be a critical factor in the remodeling processes of CRS. The objective of our research is to evaluate the differences between CRS and normal subjects and between chronic rhinosinusitis without nasal poiys （CRSsNP） and chronic rhinosinusitis with nasal polys （CRSwNP） in the regulation of EGF pathways and the regulating proliferative position of classic Ras/Raf/MEK/ERK pathways. Methods We evaluated the proliferation rates of ethmoidal mucosal cells before and after stimulation with EGF, epidermal growth factor receptor （EGFR） kinase inhibitor AG1478, and extracellular signal-regulated kinase 1/2 （ERKI/2）inhibitor PD98059 using MTT assays. We also analyzed the sinonasal epithelial cells collected from control subjects and patients with CRS subtypes CRSsNP and CRSwNP for the expression of ERK1/2, phosphorylated ERK1/2, P21, P15, and P27 using western blotting analyses. Results The proliferation rates of sinonasal epithelial cells before and after EGF stimulation were lower in CRS patients than in the controls. AG1478 or PD98059 inhibitor treatment of control epithelial cells did not result in a significant difference in proliferation. Although, AG1478 and PD98059,inhibited the proliferation of CRS cells, the degree of proliferation inhibition was markedly different in CRSsNP. AG1478 suppressed the proliferation of CRSwNP epithelial cells, whereas PD98059 had no effect. The ratio of ERK1/2 phosphorylation in CRS cells was lower than that of the control cells. Cyclin-dependent kinase inhibitors were highly expressed in CRS cells compared with that of control cells. ERK1/2 and P27 showed differential expression in CRSsNP and CRSwNP. Conclusions Differences existed in EGF pathways in CRS patients and normal subjects as well as in CRSsNP and CRSwNP. Classical Ras/Raf/MEK/ERK pathway may assume absolute superiority in control cells. Ras/Raf/MEK/ERK classical pathway and other pathways might be active at the same time to stimulate epithelial cell proliferation in CRSsNP. The function of Ras/Raf/MEK/ERK classical pathway was weaker in CRSwNP than in CRSsNP and when the classical pathway was blocked in CRSwNP, some other pathway could have completely compensated the proliferation induced by the Ras/Raf/MEK/ERK pathway.展开更多
10号染色体同源丢失性磷酸酶与张力蛋白(phosphatase and tensin homology deleted on chromosome ten,PTEN)基因在子宫内膜癌中的严重丢失,是探讨子宫内膜癌发病机制的研究热点。PTEN基因通过影响下游磷脂酰肌醇3激酶/蛋白激酶B(phosph...10号染色体同源丢失性磷酸酶与张力蛋白(phosphatase and tensin homology deleted on chromosome ten,PTEN)基因在子宫内膜癌中的严重丢失,是探讨子宫内膜癌发病机制的研究热点。PTEN基因通过影响下游磷脂酰肌醇3激酶/蛋白激酶B(phosphatidylinositol 3-kinase/protein kinase B,PI3K/Akt)/哺乳动物雷帕霉素靶向(mammalian target of rapamycin,mTOR)、黏着斑激酶(focal adhesion kinase,FAK)和丝裂原激活蛋白激酶(mitogen-activated protein kinase,MAPK)这3条信号途径来调节细胞的生长、增殖、凋亡以及血管生长等,该基因发生丢失或突变均可导致肿瘤的发生。本文就PTEN基因和表皮生长因子受体(epidermal growth factor receptor,EGFR)信号通路及其下游信号通路的联系与子宫内膜癌发生发展研究的最新进展进行综述,为子宫内膜癌的基因诊断和治疗提供理论参考。展开更多
基金grants fromthe Chinese Academy of Sciences (No. KJ951-BI608), the National Natural Sciences FOundation ofChina (No. 39625007 and
文摘We reported in this manuscript that TGF-beta1 induces apoptosis in AML12 murine hepatocytes, which is associated with the activation of p38 MAPK signaling pathway. SB202190, a specific inhibitor of p38 MAPK, strongly inhibited the TGF-beta1-induced apoptosis and PAI-1 promoter activity. Treatment of cells with TGF-beta1 activates p38. Furthermore, over-expression of dominant negative mutant p38 also reduced the TGF-beta1-induced apoptosis. The data indicate that the activation of p38 is involved in TGF-beta1-mediated gene expression and apoptosis.
文摘Background Aberrant epithelial repair has been observed in chronic rhinosinusitis （CRS） patients; however, the mechanism of epithelial cell repair regulation is unclear. Epidermal growth factor （EGF） plays an important role in regulating epithelial cell repair in lower airway and may be a critical factor in the remodeling processes of CRS. The objective of our research is to evaluate the differences between CRS and normal subjects and between chronic rhinosinusitis without nasal poiys （CRSsNP） and chronic rhinosinusitis with nasal polys （CRSwNP） in the regulation of EGF pathways and the regulating proliferative position of classic Ras/Raf/MEK/ERK pathways. Methods We evaluated the proliferation rates of ethmoidal mucosal cells before and after stimulation with EGF, epidermal growth factor receptor （EGFR） kinase inhibitor AG1478, and extracellular signal-regulated kinase 1/2 （ERKI/2）inhibitor PD98059 using MTT assays. We also analyzed the sinonasal epithelial cells collected from control subjects and patients with CRS subtypes CRSsNP and CRSwNP for the expression of ERK1/2, phosphorylated ERK1/2, P21, P15, and P27 using western blotting analyses. Results The proliferation rates of sinonasal epithelial cells before and after EGF stimulation were lower in CRS patients than in the controls. AG1478 or PD98059 inhibitor treatment of control epithelial cells did not result in a significant difference in proliferation. Although, AG1478 and PD98059,inhibited the proliferation of CRS cells, the degree of proliferation inhibition was markedly different in CRSsNP. AG1478 suppressed the proliferation of CRSwNP epithelial cells, whereas PD98059 had no effect. The ratio of ERK1/2 phosphorylation in CRS cells was lower than that of the control cells. Cyclin-dependent kinase inhibitors were highly expressed in CRS cells compared with that of control cells. ERK1/2 and P27 showed differential expression in CRSsNP and CRSwNP. Conclusions Differences existed in EGF pathways in CRS patients and normal subjects as well as in CRSsNP and CRSwNP. Classical Ras/Raf/MEK/ERK pathway may assume absolute superiority in control cells. Ras/Raf/MEK/ERK classical pathway and other pathways might be active at the same time to stimulate epithelial cell proliferation in CRSsNP. The function of Ras/Raf/MEK/ERK classical pathway was weaker in CRSwNP than in CRSsNP and when the classical pathway was blocked in CRSwNP, some other pathway could have completely compensated the proliferation induced by the Ras/Raf/MEK/ERK pathway.
