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61.
目的观察趋化因子CCL22对肺癌SBC-5细胞迁移和侵袭能力的影响。方法取肺癌细胞系SBC-5细胞,RPMI-1640培养基培养,5%CO2培养箱孵育,清洗消化后传代培养。予100ng/m L的CCL22诱导肺癌SBC-5细胞,设Control组、CCL22组(100ng/m L)、MIX组(CCL22 100ng/m L+蛋白激酶抑制剂U0126 10μmol),观察细胞迁移及侵袭能力的变化;加入蛋白激酶抑制剂(U0126)后细胞迁移及侵袭能力的变化。结果 CCL22诱导肺癌SBC-5细胞后,CCL22组细胞迁移距离(351.9±16.4)μm,明显大于Control组的(112.6±27.2)μm和MIX组的(145.1±29.6)μm(P0.05),MIX组和Control组比较差异无统计学意义(P0.05)。CCL22组平均侵袭细胞数(505.5±66.3)个,显著高于Control组的(199.2±32.8)个和MIX组的(95.7±19.1)个(P0.05),MIX组明显低于Control组(P0.05)。结论趋化因子CCL22可在体外诱导肺癌SBC-5细胞迁移和侵袭,而蛋白激酶抑制剂(U0126)可抑制CCL22诱导肺癌细胞的迁移及侵袭。 相似文献
62.
Miao-Yun Long Hong-Hao Li Xin-Zhi Pen Ming-Qing Huang Ding-Yuan Luo Pei-Shun Wang 《The Kaohsiung journal of medical sciences》2014,30(5):224-228
This study investigated the expression and role of chemokine receptor-4 (CXCR4) in bone marrow mesenchymal stem cells (BMSCs) from experimental rats with abdominal aortic aneurysms (AAA) for migration of BMSCs. Sprague–Dawley rats were divided into an experimental group and control group (n = 18 each). AAA was induced with 0.75 M solution infiltrate for 30 minutes, after which the abdomen was rinsed and closed. Saline was used in place of CaCl2 in the control group. CD34 and CD29 were detected by flow cytometry, the gene and protein expression of CXCR4 were detected by real-time polymerase chain reaction and western blot, respectively. The migration of BMSCs with stromal-derived factor-1 was detected by Transwell chamber. CD34 expression was negative and CD29 expression was positive. The gene and protein expression of CXCR4 were significantly higher in experimental group than them in control group (p < 0.05), the migration ability of BMSCs from the experimental group was significantly higher than that from the control group (p < 0.05). Stromal-derived factor -1/CXCR4 can enhance the migration of BMSCs in vitro in a rat AAA model. 相似文献
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Tingfang Yi Bo Zhai Yonghao Yu Yoshikawa Kiyotsugu Thomas Raschle Manuel Etzkorn Hee-Chan Seo Michal Nagiec Rafael E. Luna Ellis L. Reinherz John Blenis Steven P. Gygi Gerhard Wagner 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(21):E2182-E2190
Breast cancer is the leading cause of cancer-related mortality in women worldwide, with an estimated 1.7 million new cases and 522,000 deaths around the world in 2012 alone. Cancer stem cells (CSCs) are essential for tumor reoccurrence and metastasis which is the major source of cancer lethality. G protein-coupled receptor chemokine (C-X-C motif) receptor 4 (CXCR4) is critical for tumor metastasis. However, stromal cell-derived factor 1 (SDF-1)/CXCR4–mediated signaling pathways in breast CSCs are largely unknown. Using isotope reductive dimethylation and large-scale MS-based quantitative phosphoproteome analysis, we examined protein phosphorylation induced by SDF-1/CXCR4 signaling in breast CSCs. We quantified more than 11,000 phosphorylation sites in 2,500 phosphoproteins. Of these phosphosites, 87% were statistically unchanged in abundance in response to SDF-1/CXCR4 stimulation. In contrast, 545 phosphosites in 266 phosphoproteins were significantly increased, whereas 113 phosphosites in 74 phosphoproteins were significantly decreased. SDF-1/CXCR4 increases phosphorylation in 60 cell migration- and invasion-related proteins, of them 43 (>70%) phosphoproteins are unrecognized. In addition, SDF-1/CXCR4 upregulates the phosphorylation of 44 previously uncharacterized kinases, 8 phosphatases, and 1 endogenous phosphatase inhibitor. Using computational approaches, we performed system-based analyses examining SDF-1/CXCR4–mediated phosphoproteome, including construction of kinase–substrate network and feedback regulation loops downstream of SDF-1/CXCR4 signaling in breast CSCs. We identified a previously unidentified SDF-1/CXCR4-PKA-MAP2K2-ERK signaling pathway and demonstrated the feedback regulation on MEK, ERK1/2, δ-catenin, and PPP1Cα in SDF-1/CXCR4 signaling in breast CSCs. This study gives a system-wide view of phosphorylation events downstream of SDF-1/CXCR4 signaling in breast CSCs, providing a resource for the study of CSC-targeted cancer therapy.Breast cancer is the most common cancer in women, with an estimated 1.7 million new cases and 522,000 deaths around the world in 2012 alone. Tumor metastasis is the major source of cancer lethality. Cancer stem cells (CSCs) are small-percentage subpopulation within tumors, which are essential for tumor reoccurrence and metastasis (1). G protein-coupled receptor CXCR4 is critical for tumor growth and metastasis and plays important roles in CSC migration, invasion, and proliferation (2). Chemokine stromal cell-derived factor 1 (SDF-1) (CXCL-12) binds to chemokine (C-X-C motif) receptor 4 (CXCR4) and induces SDF-1/CXCR4 signaling. SDF-1 or CXCR4 knockout mice are embryonic lethal. SDF-1 and CXCR4 are vital for tumor angiogenesis and metastasis (3). The large-scale signal transduction and the feedback regulation downstream of SDF-1/CXCR4 signaling in breast CSCs are unknown but critical to understanding the cellular physiology of breast tumor regrowth and metastasis.Protein phosphorylation and dephosphorylation are essential for cellular signal processing (4). Dynamic regulation of reversible, site-specific protein phosphorylation is critical to the signaling networks that regulate CSC self-renewal, differentiation, and metastasis. Protein-reversible phosphorylation has been extensively analyzed in examining one or a few protein phosphorylation events that affect CSC signaling (1). However, the phosphoproteome composed by protein kinase-driven and phosphatase-regulated signaling networks largely controls CSC fate. Therefore, large-scale analysis of differentially regulated protein phosphorylation is central to understanding complex cellular events, such as CSC maintenance and dissemination.To unveil the signal transduction downstream of SDF-1/CXCR4 signaling in CSCs, in this study we have carried out isotope reductive dimethylation and large-scale liquid chromatography tandem mass spectrometry (LC-MS/MS)-based phosphoproteomic profiling and quantification in human breast CSCs upon SDF-1/CXCR4 stimulation. The phosphorylation events presented here include SDF-1/CXCR4–mediated phosphorylation sites in several key kinases and phosphatases, and several important signaling pathways in breast CSCs. 相似文献
65.
《Expert Review of Clinical Immunology》2013,9(5):523-534
Graft-versus-host disease (GVHD) remains a significant complication that greatly enhances morbidity and mortality associated with hematopoietic stem cell transplantation. Key immunoregulatory molecules have been implicated in the pathogenesis of GVHD, but the mechanisms by which these molecules affect the incidence and severity of GVHD have not been fully elucidated. The effects of genetic polymorphisms in immunoregulatory molecules, including cytokines, costimulatory and adhesion molecules, pharmacogenes and growth factors, have been shown to play a central role in GVHD. The results of these polymorphism studies contribute to the identification of predictive risk factors for GVHD based on individual polymorphism makeup. This review summarizes investigations of genetic polymorphisms in immunoregulatory molecules significantly associated with GVHD over the last 5 years. 相似文献
66.
《Expert Review of Clinical Immunology》2013,9(3):343-349
The fields of regulatory T (Treg) cells and chemokines/chemokine receptors have progressed rapidly in the last few years. Treg cells, especially CD4+CD25+ Treg cells, play a critical role in maintaining self-tolerance and immune homeostasis. Chemokines and chemokine receptors are crucial for lymphoid development, homing and immunological regulation. This review will discuss the biological effects of chemokines and chemokine receptors on regulating the migration and development of CD4+CD25+ Treg cells, and the potential clinical implications of these findings when considering chemokine receptors as therapeutic targets. 相似文献
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检测不同临床阶段Graves病(GD)患者和正常对照者血清CXC趋化因子配体10(CXCL10),发现GD未治疗组及复发组高于GD缓解组及正常对照组(P<0.01),且前2组间差异也有统计学意义(P<0.01),后2组间差异无统计学意义(P>0.05).血清CXCL10与FT3、FT4水平呈正相关,与TSH水平呈负相关(均P<0.01).多元线性回归分析显示:CXCL10是影响FT3、FT4、TSH水平的危险因素(P<0.01). 相似文献
69.
Fujiwara A Kobayashi H Masuya M Maruyama M Nakamura S Ibata H Fujimoto H Ohnishi M Urawa M Naito M Takagi T Kobayashi T Gabazza EC Takei Y Taguchi O 《Respirology (Carlton, Vic.)》2012,17(4):693-698
Background and objective: Interstitial lung diseases (ILD) are characterized by progressive interstitial pulmonary fibrosis and a decline in lung function. Fibrocytes are bone marrow‐derived mesenchymal progenitor cells that may play a role in the pathogenesis of pulmonary fibrosis. Circulating fibrocyte numbers have been correlated with the prognosis of patients with idiopathic pulmonary fibrosis. The aim of the present study was to evaluate the relationship between circulating fibrocytes, and parameters of disease activity and progression in several groups of patients with ILD. Methods: The study population comprised 41 patients with ILD and seven healthy control subjects. Circulating CD45+ collagen‐I+ fibrocytes were evaluated by flow cytometry. Results: The number of circulating fibrocytes was significantly increased in all patients with ILD and particularly in patients with idiopathic interstitial pneumonitis and interstitial pneumonitis associated with collagen vascular disease as compared with healthy control subjects. The numbers of circulating fibrocytes were significantly correlated with pulmonary function test parameters and with serum levels of sialylated carbohydrate antigen, a marker of disease activity. Temporal changes in circulating fibrocyte numbers were evaluated in two patients, and the results suggested that these changes correlated with the activity of ILD. Conclusions: The results from this study provide further evidence for the role of circulating fibrocytes in fibrotic lung diseases. 相似文献
70.