The Raf/MEK/extraceUular signal-regulated kinase （ERK） pathway has a pivotal role in facilitating cell proliferation, and its deregulated activation is a central signature of many epithelial cancers. However paradox...The Raf/MEK/extraceUular signal-regulated kinase （ERK） pathway has a pivotal role in facilitating cell proliferation, and its deregulated activation is a central signature of many epithelial cancers. However paradoxically, sustained activity of Raf/MEK/ERK can also result in growth arrest in many different cell types. This anti-proliferative Raf/MEK/ERK signaling also has physiological significance, as exemplified by its potential as a tumor suppressive mechanism. Therefore, significant questions include in which cell types and by what mechanisms this pathway can mediate such an opposing context of signaling. Particularly, our understating of the role of ERK1 and ERK2, the focal points of pathway signaling, in growth arrest signaling is still limited. This review discusses these aspects of Raf/MEK/ ERK-mediated growth arrest signaling.展开更多
BACKGROUND Hepatic stellate cell(HSC)hyperactivation is a central link in liver fibrosis development.HSCs perform aerobic glycolysis to provide energy for their activation.Focal adhesion kinase(FAK)promotes aerobic gl...BACKGROUND Hepatic stellate cell(HSC)hyperactivation is a central link in liver fibrosis development.HSCs perform aerobic glycolysis to provide energy for their activation.Focal adhesion kinase(FAK)promotes aerobic glycolysis in cancer cells or fibroblasts,while FAK-related non-kinase(FRNK)inhibits FAK phosphorylation and biological functions.AIM To elucidate the effect of FRNK on liver fibrosis at the level of aerobic glycolytic metabolism in HSCs.METHODS Mouse liver fibrosis models were established by administering CCl4,and the effect of FRNK on the degree of liver fibrosis in the model was evaluated.Transforming growth factor-β1 was used to activate LX-2 cells.Tyrosine phosphorylation at position 397(pY397-FAK)was detected to identify activated FAK,and the expression of the glycolysis-related proteins monocarboxylate transporter 1(MCT-1)and enolase1(ENO1)was assessed.Bioinformatics analysis was performed to predict putative binding sites for c-myc in the ENO1 promoter region,which were validated with chromatin immunoprecipitation(ChIP)and dual luciferase reporter assays.RESULTS The pY397-FAK level was increased in human fibrotic liver tissue.FRNK knockout promoted liver fibrosis in mouse models.It also increased the activation,migration,proliferation and aerobic glycolysis of primary hepatic stellate cells(pHSCs)but inhibited pHSC apoptosis.Nevertheless,opposite trends for these phenomena were observed after exogenous FRNK treatment in LX-2 cells.Mechanistically,the FAK/Ras/c-myc/ENO1 pathway promoted aerobic glycolysis,which was inhibited by exogenous FRNK.CONCLUSION FRNK inhibits aerobic glycolysis in HSCs by inhibiting the FAK/Ras/c-myc/ENO1 pathway,thereby improving liver fibrosis.FRNK might be a potential target for liver fibrosis treatment.展开更多
目的:研究黏着斑相关非激酶(focal adhesion kinase related non-kinase,FRNK)对人乳腺癌MCF-7细胞增殖的抑制作用及相关机制。方法:通过RT-PCR方法克隆目的基因FRNK,构建pcDNA3.1-FRNK重组质粒;经脂质体分别介导重组质粒(pcDNA3.1-FRNK...目的:研究黏着斑相关非激酶(focal adhesion kinase related non-kinase,FRNK)对人乳腺癌MCF-7细胞增殖的抑制作用及相关机制。方法:通过RT-PCR方法克隆目的基因FRNK,构建pcDNA3.1-FRNK重组质粒;经脂质体分别介导重组质粒(pcDNA3.1-FRNK)、阳性对照质粒(pcDNA3.1-GFP)和空质粒(pcDNA3.1)转染MCF-7细胞,以正常MCF-7细胞作为空白对照;通过检测转染后细胞FRNK蛋白的表达,并结合转染pcDNA3.1-GFP后细胞表达荧光的多寡来评估转染效率;采用MTT法研究转染后12、24、48和72h各时间点细胞的增殖情况;转染质粒48h后,采用流式细胞术分析MCF-7细胞周期,Westernblot法检测细胞核内NF-κBp65的表达。结果:pcDNA3.1-FRNK质粒可经脂质体介导高效转染MCF-7细胞,促进细胞FRNK的表达,FRNK表达量在转染后48h达高峰;转染pcDNA3.1-FRNK后,MCF-7细胞增殖趋缓,且这种抑制增殖呈一定的时间依赖性;转染FRNK基因后,S+G2/M期的细胞比例较正常细胞显著下降(P<0.05);转染pcDNA3.1-FRNK后MCF-7细胞核内NF-κBp65蛋白表达减少。结论:FRNK可抑制MCF-7细胞增殖,其抑制作用与下调NF-κBp65核易位相关。展开更多
Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulat...Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK.展开更多
目的:观察黄芩汤对溃疡性结肠炎大鼠白细胞介素-6(interleukin-6,IL-6)、非受体酪氨酸激酶(just another kinase,JAK)-信号转导蛋白及转录激活因子3(signal transducer and activator of transcription,STAT3)信号通路、高迁移率族蛋白1...目的:观察黄芩汤对溃疡性结肠炎大鼠白细胞介素-6(interleukin-6,IL-6)、非受体酪氨酸激酶(just another kinase,JAK)-信号转导蛋白及转录激活因子3(signal transducer and activator of transcription,STAT3)信号通路、高迁移率族蛋白1(high mobility group box-1 protein,HMGB1)表达的影响。方法:在60只健康SD雄性大鼠(SPF级)中随机选择45只,建立溃疡性结肠炎大鼠模型,将45只溃疡性结肠炎模型大鼠按照随机数字表法分为模型组、柳氮磺胺吡啶组和黄芩汤组,每组15只,未做处理的15只大鼠设为对照组。对照组和模型组大鼠给予生理盐水灌胃,柳氮磺胺吡啶组大鼠给予柳氮磺胺吡啶片混合液灌胃,黄芩汤组大鼠给予黄芩汤灌胃,各组大鼠灌胃均持续4周,早晚各1次。4周后,比较4组大鼠结肠病理切片,观察IL-6 mRNA、JAK mRNA、STAT3 mRNA及HMGB-1 mRNA的表达,IL-6、JAK、STAT3和HMGB-1蛋白表达和血清IL-6、JAK、STAT3和HMGB-1的含量。结果:与模型组大鼠比较,柳氮磺胺吡啶组和黄芩汤组大鼠病理切片显示炎症情况显著改善(P<0.05);与模型组大鼠比较,柳氮磺胺吡啶组和黄芩汤组大鼠IL-6 mRNA、JAK mRNA、STAT3mRNA及HMGB-1 mRNA,IL-6、JAK、STAT3和HMGB-1蛋白和血清IL-6、JAK、STAT3和HMGB-1的含量均明显降低(P<0.05),其中IL-6与JAK、STAT3呈高度正相关。结论:黄芩汤治疗溃疡性结肠炎的作用机制可能是通过抑制IL-6、JAK、STAT3信号通路的激活和HMGB-1的表达,降低炎性细胞因子的产生,减少炎症反应,从而改善肠道功能,恢复肠道结构。展开更多
Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor...Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor of trehalose in the biosynthetic pathway, is an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. In addition to the plant＇s own pathway for trehalose synthesis, formation of T6P or trehalose by pathogens can result in the reprogramming of plant metabolism and development. Developmental processes that are regulated by T6P range from embryo development to leaf senescence. Some of these processes are regulated in interaction with phytohormones, such as auxin. A key interacting factor of T6P signaling in response to the environment is the protein kinase sucrose non-fermenting related kinase-1 （SnRK1）, whose catalytic activity is inhibited by T6R SnRK1 is most likely involved in the adjustment of metabolism and growth in response to starvation. The transcription factor bZlP11 has recently been identified as a new player in the T6P/SnRK1 regulatory pathway. By inhibiting SnRK1, T6P promotes biosynthetic reactions. This regulation has important consequences for crop production, for example, in the developing wheat grain and during the growth of potato tubers.展开更多
文摘The Raf/MEK/extraceUular signal-regulated kinase （ERK） pathway has a pivotal role in facilitating cell proliferation, and its deregulated activation is a central signature of many epithelial cancers. However paradoxically, sustained activity of Raf/MEK/ERK can also result in growth arrest in many different cell types. This anti-proliferative Raf/MEK/ERK signaling also has physiological significance, as exemplified by its potential as a tumor suppressive mechanism. Therefore, significant questions include in which cell types and by what mechanisms this pathway can mediate such an opposing context of signaling. Particularly, our understating of the role of ERK1 and ERK2, the focal points of pathway signaling, in growth arrest signaling is still limited. This review discusses these aspects of Raf/MEK/ ERK-mediated growth arrest signaling.
基金the National Natural Science Foundation of China,No.81860115,No.82060116 and No.81960118the Science and Technology Support Project of Guizhou Province,No.[2021]094.
文摘BACKGROUND Hepatic stellate cell(HSC)hyperactivation is a central link in liver fibrosis development.HSCs perform aerobic glycolysis to provide energy for their activation.Focal adhesion kinase(FAK)promotes aerobic glycolysis in cancer cells or fibroblasts,while FAK-related non-kinase(FRNK)inhibits FAK phosphorylation and biological functions.AIM To elucidate the effect of FRNK on liver fibrosis at the level of aerobic glycolytic metabolism in HSCs.METHODS Mouse liver fibrosis models were established by administering CCl4,and the effect of FRNK on the degree of liver fibrosis in the model was evaluated.Transforming growth factor-β1 was used to activate LX-2 cells.Tyrosine phosphorylation at position 397(pY397-FAK)was detected to identify activated FAK,and the expression of the glycolysis-related proteins monocarboxylate transporter 1(MCT-1)and enolase1(ENO1)was assessed.Bioinformatics analysis was performed to predict putative binding sites for c-myc in the ENO1 promoter region,which were validated with chromatin immunoprecipitation(ChIP)and dual luciferase reporter assays.RESULTS The pY397-FAK level was increased in human fibrotic liver tissue.FRNK knockout promoted liver fibrosis in mouse models.It also increased the activation,migration,proliferation and aerobic glycolysis of primary hepatic stellate cells(pHSCs)but inhibited pHSC apoptosis.Nevertheless,opposite trends for these phenomena were observed after exogenous FRNK treatment in LX-2 cells.Mechanistically,the FAK/Ras/c-myc/ENO1 pathway promoted aerobic glycolysis,which was inhibited by exogenous FRNK.CONCLUSION FRNK inhibits aerobic glycolysis in HSCs by inhibiting the FAK/Ras/c-myc/ENO1 pathway,thereby improving liver fibrosis.FRNK might be a potential target for liver fibrosis treatment.
文摘目的:研究黏着斑相关非激酶(focal adhesion kinase related non-kinase,FRNK)对人乳腺癌MCF-7细胞增殖的抑制作用及相关机制。方法:通过RT-PCR方法克隆目的基因FRNK,构建pcDNA3.1-FRNK重组质粒;经脂质体分别介导重组质粒(pcDNA3.1-FRNK)、阳性对照质粒(pcDNA3.1-GFP)和空质粒(pcDNA3.1)转染MCF-7细胞,以正常MCF-7细胞作为空白对照;通过检测转染后细胞FRNK蛋白的表达,并结合转染pcDNA3.1-GFP后细胞表达荧光的多寡来评估转染效率;采用MTT法研究转染后12、24、48和72h各时间点细胞的增殖情况;转染质粒48h后,采用流式细胞术分析MCF-7细胞周期,Westernblot法检测细胞核内NF-κBp65的表达。结果:pcDNA3.1-FRNK质粒可经脂质体介导高效转染MCF-7细胞,促进细胞FRNK的表达,FRNK表达量在转染后48h达高峰;转染pcDNA3.1-FRNK后,MCF-7细胞增殖趋缓,且这种抑制增殖呈一定的时间依赖性;转染FRNK基因后,S+G2/M期的细胞比例较正常细胞显著下降(P<0.05);转染pcDNA3.1-FRNK后MCF-7细胞核内NF-κBp65蛋白表达减少。结论:FRNK可抑制MCF-7细胞增殖,其抑制作用与下调NF-κBp65核易位相关。
基金Supported by the National Natural Science Foundation of China(30700822)
文摘Proline-rich tyrosine kinase 2 (Pyk2) is a nonreceptor protein tyrosine kinase,which is also known as Ca2 +-dependent tyrosine kinase or related adhesion focal tyrosine kinase.Pyk2 activation exerts a critical regulatory mechanism for various physiological processes including cytoskeleton function,regulation of cell growth and death,modulation of ion channels and multiple signaling events.However,mechanisms underlying the functional diversity of Pyk2 are not clear.A Pyk2 isoform that encodes only part of the C-terminal domain of Pyk2,named as PRNK (Pyk2-related non-kinase),acts as a dominant-negative inhibitor of Pyk2-dependent signaling by displacing Pyk2 from focal adhesions.Research on functional PRNK probably provides new potential inhibitory tool targeting Pyk2 and makes it possible to explore more of Pyk2 pathological mechanism.PRNK is a promising candidate targeting Pyk2 modulation.This review focuses on the functional investigation of Pyk2 and its structure and localization,including recent research with inhibitory strategies targeting Pyk2 by the method of PRNK.
文摘目的:观察黄芩汤对溃疡性结肠炎大鼠白细胞介素-6(interleukin-6,IL-6)、非受体酪氨酸激酶(just another kinase,JAK)-信号转导蛋白及转录激活因子3(signal transducer and activator of transcription,STAT3)信号通路、高迁移率族蛋白1(high mobility group box-1 protein,HMGB1)表达的影响。方法:在60只健康SD雄性大鼠(SPF级)中随机选择45只,建立溃疡性结肠炎大鼠模型,将45只溃疡性结肠炎模型大鼠按照随机数字表法分为模型组、柳氮磺胺吡啶组和黄芩汤组,每组15只,未做处理的15只大鼠设为对照组。对照组和模型组大鼠给予生理盐水灌胃,柳氮磺胺吡啶组大鼠给予柳氮磺胺吡啶片混合液灌胃,黄芩汤组大鼠给予黄芩汤灌胃,各组大鼠灌胃均持续4周,早晚各1次。4周后,比较4组大鼠结肠病理切片,观察IL-6 mRNA、JAK mRNA、STAT3 mRNA及HMGB-1 mRNA的表达,IL-6、JAK、STAT3和HMGB-1蛋白表达和血清IL-6、JAK、STAT3和HMGB-1的含量。结果:与模型组大鼠比较,柳氮磺胺吡啶组和黄芩汤组大鼠病理切片显示炎症情况显著改善(P<0.05);与模型组大鼠比较,柳氮磺胺吡啶组和黄芩汤组大鼠IL-6 mRNA、JAK mRNA、STAT3mRNA及HMGB-1 mRNA,IL-6、JAK、STAT3和HMGB-1蛋白和血清IL-6、JAK、STAT3和HMGB-1的含量均明显降低(P<0.05),其中IL-6与JAK、STAT3呈高度正相关。结论:黄芩汤治疗溃疡性结肠炎的作用机制可能是通过抑制IL-6、JAK、STAT3信号通路的激活和HMGB-1的表达,降低炎性细胞因子的产生,减少炎症反应,从而改善肠道功能,恢复肠道结构。
文摘Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor of trehalose in the biosynthetic pathway, is an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. In addition to the plant＇s own pathway for trehalose synthesis, formation of T6P or trehalose by pathogens can result in the reprogramming of plant metabolism and development. Developmental processes that are regulated by T6P range from embryo development to leaf senescence. Some of these processes are regulated in interaction with phytohormones, such as auxin. A key interacting factor of T6P signaling in response to the environment is the protein kinase sucrose non-fermenting related kinase-1 （SnRK1）, whose catalytic activity is inhibited by T6R SnRK1 is most likely involved in the adjustment of metabolism and growth in response to starvation. The transcription factor bZlP11 has recently been identified as a new player in the T6P/SnRK1 regulatory pathway. By inhibiting SnRK1, T6P promotes biosynthetic reactions. This regulation has important consequences for crop production, for example, in the developing wheat grain and during the growth of potato tubers.
