Background Cellular Repressor of E1A-stimu-lated gene(CREG) is widely expressed in adult tissues such as the brain,heart,lung,liver,intestine and kidney in mice.It is not known whether tissue CREG is decreased in the ...Background Cellular Repressor of E1A-stimu-lated gene(CREG) is widely expressed in adult tissues such as the brain,heart,lung,liver,intestine and kidney in mice.It is not known whether tissue CREG is decreased in the common setting of myocardial infarction which may lead to heart failure.We studied the expression and protein localization of CREG and its main receptor(IFR2R) in a mouse model of myocardial infarction.Methods Male mice were randomized to proximal left anterior descending ligation.The animals were killed on day 1,3,7,14,and 28 after ligation to examine gene expression and protein production of CREG and IGF2R from the infarct,peri-infarct,and contralateral zones of infarcted heart.Results There was decreased CREG mRNA production throughout the myocardium at dav 1,and the expression gradually increased at day 28 after myocardial infarction.The decreased expression of this glycoprotein was not confined strictly to the infarct or peri-infarct zones but also expressed by cardiac myocytes within the myocardium in the contralateral normal zone.Levels of CREG protein in the infarct and peri-infarct zones declined to 1/3- to 1/2-fold of normal levels and declined to 1/2- to 2/3- fold in the contralateral zone.Finally,the expression of the IGF2R mRNA transcripts was downregulated at day 3 and 7 after ligation in the infarct and peri-infarct zones,suggesting that the signal transduction pathways necessary for CREG in the heart remain intact as CREG biosynthesis decreases. Conclusions CREG is constantly present in a model of large myocardial infarction and is decreased at the early stage within the myocardium.The decreased expression of this glycoprotein is not only confined strictly to the infarct or periinfarct zone but also is expressed by cardiac myocytes within the myocardium contralateral to the infarct.Therefore CREG production decreased due to myocardial stress response to injury.展开更多
目的探讨人转录活化因子阿尔法又称富含嘌呤成份(或元件)结合蛋白(human transcriptional activator alpha,also named as purine-rich element binding protein alpha,Purα)对早期生长反应蛋白-1(Egr-1)基因表达的调控作用。方法利用...目的探讨人转录活化因子阿尔法又称富含嘌呤成份(或元件)结合蛋白(human transcriptional activator alpha,also named as purine-rich element binding protein alpha,Purα)对早期生长反应蛋白-1(Egr-1)基因表达的调控作用。方法利用PCR技术从U87MG细胞基因组DNA中扩增Egr-1基因启动子近5’端约700bp的DNA片段,将扩增的DNA片段克隆到萤火虫荧光素酶报告基因载体p GL3-Basic的相应酶切位点,构建成含有Egr-1启动子的萤火虫荧光素酶报告基因载体(p GL3-Basic-Egr-1)并通过酶切和测序进行鉴定。通过萤火虫荧光素酶实验对p GL3-Basic-Egr-1启动子的活性进行测定并检测Purα蛋白对p GL3-Basic-Egr-1启动子活性的作用。通过q PCR和Western blot实验检测Purα蛋白在转录和翻译水平对Egr-1基因表达的调控作用。结果通过序列测定和酶切分析证实所构建的含Egr-1基因启动子的报告载体与实验设计完全一致,萤火虫荧光素酶分析实验证实所构建的p GL3-Basic-Egr-1启动子序列正确并具有活性,Purα蛋白可以抑制p GL3-Basic-Egr-1启动子的活性,过表达Purα可以在转录和翻译水平下调Egr-1基因的表达。结论 Purα蛋白具有下调Egr-1基因表达的作用。展开更多
AIM: To observe the growth suppression effect of exogenous introduction of early growth response gene-1 (Egr-1 gene) on esophageal carcinoma tissue as well as on esophageal carcinoma cell line Eca109 and to explore th...AIM: To observe the growth suppression effect of exogenous introduction of early growth response gene-1 (Egr-1 gene) on esophageal carcinoma tissue as well as on esophageal carcinoma cell line Eca109 and to explore the potential application of Egr-1 gene in gene therapy of tumor. METHODS: Eukaryotic expression vector of PCMV-Egr-1 plasmid was introduced into Eca109 cell line which expressed no Egr-1 protein originally with lipofectamine transfection method. The introduction and expression of PCMV-Egr-1 plasmid into Eca109 cell line was confirmed by G418 selection culture, PCR amplification of neogene contained in the vector, Western blot analysis and immunocytochemical analysis. The cell growth curve, soft agar colony formation rate and tumorigenicity in SCID mice were examined to demonstrate the growth suppression effect of exogenous Egr-1 gene on Eca109 cell line. The Egr-1 mRNA and Egr-1 protein were also detected in 50 surgical specimens of esophageal carcinoma by in situ hybridization and immunohistochemistry. RESULTS: Exogenous Egr-1 gene was introduced successfully into Eca109 cell line and expressed Egr-1 protein stably. The transfected Eca109 cell line grew more slowly than control Eca109 as shown by cell growth curves, the soft agar colony formation rate (4.0% vs 6.9%, P 【 0.01) and the average growth rate of tumor in SCID mice (35.5 +/- 7.6 vs 65.8 +/- 7.6, P 【 0.05). The expression level of Egr-1 mRNA and protein significantly increased in dysplastic epithelia adjacent to cancer rather than in cancer tissues (65.8% vs 20.0% by ISH and 57.9% vs 0.01). CONCLUSION: Exogenous Egr-1 gene shows the strong effect of growth inhibition in Eca109 cell line. Egr-1 in the cancer tissue shows down-regulated expression that supports the inhibited function of Egr-1 in cancer growth and suggests Egr-1 may have an important role in gene therapy of esophageal carcinoma.展开更多
OBJECTIVE: To clarify the role of these cyclins in human gastric cancer. METHODS: 38 gastric cancer patients, 29 first degree relatives of gastric cancer patients, as well as 18 healthy subjects were included. The mRN...OBJECTIVE: To clarify the role of these cyclins in human gastric cancer. METHODS: 38 gastric cancer patients, 29 first degree relatives of gastric cancer patients, as well as 18 healthy subjects were included. The mRNA expression of cyclins D1, D2, D3 and E in gastric biopsies was evaluated by RT-PCR analysis using specific primers. Histomorphological features such as intestinal metaplasia, atrophy, H. pylori infection and severity of gastritis were determined by the updated Sydney System. RESULTS: Significant mRNA overexpression was found for cyclins D2, D3 and E compared with healthy normal specimen, but cyclin D1 expression was not different between tumor and normal tissues. In addition, cyclin D2 and D3 overexpression was significantly more frequent in first degree relatives than in healthy controls (P展开更多
文摘Background Cellular Repressor of E1A-stimu-lated gene(CREG) is widely expressed in adult tissues such as the brain,heart,lung,liver,intestine and kidney in mice.It is not known whether tissue CREG is decreased in the common setting of myocardial infarction which may lead to heart failure.We studied the expression and protein localization of CREG and its main receptor(IFR2R) in a mouse model of myocardial infarction.Methods Male mice were randomized to proximal left anterior descending ligation.The animals were killed on day 1,3,7,14,and 28 after ligation to examine gene expression and protein production of CREG and IGF2R from the infarct,peri-infarct,and contralateral zones of infarcted heart.Results There was decreased CREG mRNA production throughout the myocardium at dav 1,and the expression gradually increased at day 28 after myocardial infarction.The decreased expression of this glycoprotein was not confined strictly to the infarct or peri-infarct zones but also expressed by cardiac myocytes within the myocardium in the contralateral normal zone.Levels of CREG protein in the infarct and peri-infarct zones declined to 1/3- to 1/2-fold of normal levels and declined to 1/2- to 2/3- fold in the contralateral zone.Finally,the expression of the IGF2R mRNA transcripts was downregulated at day 3 and 7 after ligation in the infarct and peri-infarct zones,suggesting that the signal transduction pathways necessary for CREG in the heart remain intact as CREG biosynthesis decreases. Conclusions CREG is constantly present in a model of large myocardial infarction and is decreased at the early stage within the myocardium.The decreased expression of this glycoprotein is not only confined strictly to the infarct or periinfarct zone but also is expressed by cardiac myocytes within the myocardium contralateral to the infarct.Therefore CREG production decreased due to myocardial stress response to injury.
文摘目的探讨人转录活化因子阿尔法又称富含嘌呤成份(或元件)结合蛋白(human transcriptional activator alpha,also named as purine-rich element binding protein alpha,Purα)对早期生长反应蛋白-1(Egr-1)基因表达的调控作用。方法利用PCR技术从U87MG细胞基因组DNA中扩增Egr-1基因启动子近5’端约700bp的DNA片段,将扩增的DNA片段克隆到萤火虫荧光素酶报告基因载体p GL3-Basic的相应酶切位点,构建成含有Egr-1启动子的萤火虫荧光素酶报告基因载体(p GL3-Basic-Egr-1)并通过酶切和测序进行鉴定。通过萤火虫荧光素酶实验对p GL3-Basic-Egr-1启动子的活性进行测定并检测Purα蛋白对p GL3-Basic-Egr-1启动子活性的作用。通过q PCR和Western blot实验检测Purα蛋白在转录和翻译水平对Egr-1基因表达的调控作用。结果通过序列测定和酶切分析证实所构建的含Egr-1基因启动子的报告载体与实验设计完全一致,萤火虫荧光素酶分析实验证实所构建的p GL3-Basic-Egr-1启动子序列正确并具有活性,Purα蛋白可以抑制p GL3-Basic-Egr-1启动子的活性,过表达Purα可以在转录和翻译水平下调Egr-1基因的表达。结论 Purα蛋白具有下调Egr-1基因表达的作用。
基金Supported by the National Natural Science Foundation of China,No.39670298.
文摘AIM: To observe the growth suppression effect of exogenous introduction of early growth response gene-1 (Egr-1 gene) on esophageal carcinoma tissue as well as on esophageal carcinoma cell line Eca109 and to explore the potential application of Egr-1 gene in gene therapy of tumor. METHODS: Eukaryotic expression vector of PCMV-Egr-1 plasmid was introduced into Eca109 cell line which expressed no Egr-1 protein originally with lipofectamine transfection method. The introduction and expression of PCMV-Egr-1 plasmid into Eca109 cell line was confirmed by G418 selection culture, PCR amplification of neogene contained in the vector, Western blot analysis and immunocytochemical analysis. The cell growth curve, soft agar colony formation rate and tumorigenicity in SCID mice were examined to demonstrate the growth suppression effect of exogenous Egr-1 gene on Eca109 cell line. The Egr-1 mRNA and Egr-1 protein were also detected in 50 surgical specimens of esophageal carcinoma by in situ hybridization and immunohistochemistry. RESULTS: Exogenous Egr-1 gene was introduced successfully into Eca109 cell line and expressed Egr-1 protein stably. The transfected Eca109 cell line grew more slowly than control Eca109 as shown by cell growth curves, the soft agar colony formation rate (4.0% vs 6.9%, P 【 0.01) and the average growth rate of tumor in SCID mice (35.5 +/- 7.6 vs 65.8 +/- 7.6, P 【 0.05). The expression level of Egr-1 mRNA and protein significantly increased in dysplastic epithelia adjacent to cancer rather than in cancer tissues (65.8% vs 20.0% by ISH and 57.9% vs 0.01). CONCLUSION: Exogenous Egr-1 gene shows the strong effect of growth inhibition in Eca109 cell line. Egr-1 in the cancer tissue shows down-regulated expression that supports the inhibited function of Egr-1 in cancer growth and suggests Egr-1 may have an important role in gene therapy of esophageal carcinoma.
文摘OBJECTIVE: To clarify the role of these cyclins in human gastric cancer. METHODS: 38 gastric cancer patients, 29 first degree relatives of gastric cancer patients, as well as 18 healthy subjects were included. The mRNA expression of cyclins D1, D2, D3 and E in gastric biopsies was evaluated by RT-PCR analysis using specific primers. Histomorphological features such as intestinal metaplasia, atrophy, H. pylori infection and severity of gastritis were determined by the updated Sydney System. RESULTS: Significant mRNA overexpression was found for cyclins D2, D3 and E compared with healthy normal specimen, but cyclin D1 expression was not different between tumor and normal tissues. In addition, cyclin D2 and D3 overexpression was significantly more frequent in first degree relatives than in healthy controls (P
