摘要:
Transcription factors (TFs) are modulators of gene expression that are critically important in the establishment and progression of human cancers. In the current study, the activity profiles of TFs in a normal nasopharyngeal epithelial cell line and in nasopharyngeal carcinoma (NPC) cell lines were studied using oligonucleotide array-based TF assays. Compared to the normal epithelial cell line NP69, nine TFs in the non-meta static NPC cell line (6-10B) and eight TFs in a metastatic NPC cell line (5-8F) were upregulated. Among upregulated TFs, Sp1, AP2, and ATF/CREB families exhibited relatively high activities in NPC cell lines. Transcription levels of Sp1, ATF-1, ATF-2, AP2 alpha, AP2 gamma, and CREB I were higher in 5-8F cells than in 6-10B cells. In addition, higher expression of the Sp1 target genes MMP-9 and VEGF was observed in 5-8F cells. Sp1 silencing reduced VEGF and MMP-9 expression. Inhibition of Sp1 expression and activity in 5-8F cells by mithramycin resulted in downregulated expression and secretion of MMP-9 and VEGF, concomitant with inhibition of cell migration and invasion. These results suggest that dynamic changes in TF activities Occur in NPC cells and that these changes may play important roles in regulating the expression of-genes associated with the development and progression of NPC. J. Cell. Biochem. 109: 173-183, 2010. (C) 2009 Wiley-Liss, Inc.
作者机构:
[Dind D.-X.; Li G.-Y.; 胡南] Key Discipline Lab. for Natl. Def. for Biotech. in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, Hunan, China;Biology Institute, University of South China, Hengyang 421001, Hunan, China;[胡劲松; 殷杰; 吴彦琼; 刘俊] Key Discipline Lab. for Natl. Def. for Biotech. in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, Hunan, China, Biology Institute, University of South China, Hengyang 421001, Hunan, China
通讯机构:
[Wu, Y.-Q.] K;Key Discipline Lab. for Natl. Def. for Biotech. in Uranium Mining and Hydrometallurgy, University of South China, China
期刊:
JOURNAL OF CARDIOVASCULAR PHARMACOLOGY,2010年56(3):309-319 ISSN:0160-2446
通讯作者:
Tang, Chao-Ke
作者机构:
[Tan, Chun-Zhi; Tang, Chao-Ke; Liu, Xie-Hong; Yin, Kai; Tang, Ya-Ling; Mo, Zhong-Cheng; Jiang, Jin; Xiao, Ji; Cui, Li-Bao] Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Changsha, Hunan, Peoples R China.;[Liu, Xie-Hong] Changsha Med Univ, Changsha, Hunan, Peoples R China.;[Liao, Duan-Fang] Hunan Univ Chinese Med, Changsha, Hunan, Peoples R China.;[Tang, Chao-Ke] Univ S China, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Life Sci Res Ctr, Hengyang 421001, Peoples R China.
通讯机构:
[Tang, Chao-Ke] U;Univ S China, Inst Cardiovasc Res, Key Lab Atherosclerol Hunan Prov, Life Sci Res Ctr, Hengyang 421001, Peoples R China.
关键词:
ABCA1, D4-F, Cdc42/cAMP/PKA, atherosclerosis, reverse cholesterol transport
摘要:
Adenosine triphosphate-binding cassette transporter A1 (ABCA1) plays a crucial role in apolipoprotein A-I (apoA-I) binding activity and promotes cellular cholesterol efflux. ApoA-I mimetic peptide D4-F has reported to have the similar ability as apoA-I. However, the detailed mechanisms of ABCA1 regulation by D4-F are not understood. In the present study, we investigated the effects of D4-F on ABCA1 expression and ABCA1-dependent cholesterol efflux and examined the role of Cdc42/cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway on the regulation of ABCA1 by D4-F in THP-1 macrophage-derived foam cells. Results showed that D4-F stabilized ABCA1 protein and enhanced ABCA1-dependent cholesterol efflux but had no effect on ABCA1 messenger RNA expression. We also revealed that D4-F enhanced cAMP level and PKA activity and ABCA1 serine phosphorylation. Short interfering RNA of PKA led to reduction of ABCA1 serine phosphorylation and ABCA1-mediated cholesterol efflux compensated by D4-F. PKA-specific activation by PKA agonist enhanced the upregulation of ABCA1 serine phosphorylation and ABCA1-mediated cholesterol efflux by D4-F. However, ABCA1 expression did not change by treatment with PKA agonist or PKA-short interfering RNA. We found that secramine B of Cdc42 inhibitor reduced the cAMP level compensated by D4-F. These results provide evidence that D4-F enhances ABCA1 serine phosphorylation and ABCA1-dependent cholesterol efflux through Cdc42/cAMP/PKA pathway in THP-1 macrophage-derived foam cells.
摘要:
Atherosclerosis is characterized by a chronic inflammatory condition that involves numerous cellular and molecular inflammatory components. A wide array of inflammatory mediators, such as cytokines and proteins produced by macrophages and other cells, play a critical role in the development and progression of the disease. ATP-binding membrane cassette transporter A1 (ABCA1) is crucial for cellular cholesterol efflux and reverse cholesterol transport (RCT) and is also identified as an important target in antiatherosclerosis treatment. Evidence from several recent studies indicates that inflammation, along with other atherogenic-related mediators, plays distinct regulating roles in ABCA1 expression. Proatherogenic cytokines such as interferon (IFN)-γ and interleukin (IL)-1β have been shown to inhibit the expression of ABCA1, while antiatherogenic cytokines, including IL-10 and transforming growth factor (TGF)-β1, have been shown to promote the expression of ABCA1. Moreover, some cytokines such as tumor necrosis factor (TNF)-α seem to regulate ABCA1 expression in species-specific and dose-dependent manners. Inflammatory proteins such as C-reactive protein (CRP) and cyclooxygenase (COX)-2 are likely to inhibit ABCA1 expression during inflammation, and inflammation induced by lipopolysaccharide (LPS) was also found to block the expression of ABCA1. Interestingly, recent experiments revealed ABCA1 can function as an antiinflammatory receptor to suppress the expression of inflammatory factors, suggesting that ABCA1 may be the molecular basis for the interaction between inflammation and RCT. This review aims to summarize recent findings on the role of inflammatory cytokines, inflammatory proteins, inflammatory lipids, and the endotoxin-mediated inflammatory process in expression of ABCA1. Also covered is the current understanding of the function of ABCA1 in modulating the immune response and inflammation through its direct and indirect antiinflammatory mechanisms including lipid transport, high-density lipoprotein (HDL) formation and apoptosis.