Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF pro...Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF proteins is important for their transcriptional activities and biological functions. One KLF family member with important roles in cell proliferation and tumorigenesis is KLF5. The function of KLF5 is tightly controlled by post-translational modifications, including SUMOylation, phosphorylation, and ubiquitination. Recent studies from our lab and others' have demonstrated that the tumor suppressor FBW7 is an essential E3 ubiquitin ligase that targets KLF5 for ubiquitination and degradation. KLF5 contains functional Cdc4 phospho-degrons(CPDs), which are required for its interaction with FBW7. Mutation of CPDs in KLF5 blocks the ubiquitination and degradation of KLF5 by FBW7. The protein kinase Glycogen synthase kinase 3β is involved in the phosphorylation of KLF5 CPDs. In both cancer cell lines and mousemodels, it has been shown that FBW7 regulates the expression of KLF5 target genes through the modulation of KLF5 stability. In this review, we summarize the current progress on delineating FBW7-mediated KLF5 ubiquitination and degradation.展开更多
Sp1/Krüppel样因子(Sp1-like and Krüppel-like factors,Sp1/KLFs)是一组与真核细胞转录调控密切相关的锌指蛋白。Sp1/KLFs的羧基末端高度保守,含有3个串联的Cys2His2锌指结构,用于结合DNA;其氨基末端在不同的家族成员间存在...Sp1/Krüppel样因子(Sp1-like and Krüppel-like factors,Sp1/KLFs)是一组与真核细胞转录调控密切相关的锌指蛋白。Sp1/KLFs的羧基末端高度保守,含有3个串联的Cys2His2锌指结构,用于结合DNA;其氨基末端在不同的家族成员间存在较大差异,主要是通过结合辅助因子发挥转录调控作用。Sp1/KLFs的表达具有组织、细胞分布以及发育时期的特异性,它们通过调控多种富含GC或CACCC的启动子的基因的表达,参与细胞增殖、分化、凋亡和肿瘤发生、发展等多种生理、病理过程。文章综述了Sp1/KLFs的结构特征、作用机制及生物学功能。展开更多
Background Pancreatic cancer is a lethal disease that is often diagnosed at an advanced stage.There is a lack of information to predict the prognosis of pancreatic cancer.Krüppel-like factor （KLF） 8 has been fo...Background Pancreatic cancer is a lethal disease that is often diagnosed at an advanced stage.There is a lack of information to predict the prognosis of pancreatic cancer.Krüppel-like factor （KLF） 8 has been found to be deregulated in multiple cancers,and its high expression was correlated with poor prognosis.However,so far,no information was reported about the expression of KLF8 in pancreatic cancer.In the present study,we investigated,possibly for the first time,the expression of KLF8 in pancreatic cancer samples and analyzed its correlation with clinical parameters and overall survival （OS） rate.Methods We used immunohistochemical staining to detect KLF8 in 68 samples from patients who underwent surgery and its correlation with the clinicopathological characteristics.We used Kaplan-Meier curve to analyze the relationship between KLF8 expression and the OS time.Univariate analysis was performed in addition to multivariate hazard models with clinicopathological features to assess KLF8 as an independent prognostic factor.Results KLF8 was present in the cytoplasm of pancreatic cancer cells and 52.9％ of the 68 cases had positive expression.KLF8 expression was not associated with sex,age,tumor location,lymph node stage,and metastasis stage,but was associated with tumor stage （P=0.04）.Kaplan-Meier method demonstrated that patients with negative expression of KLF8 had a better prognosis.In univariate and multivariate models,KLF8 was a significant predictor of OS in pancreatic cancer.Conclusion Our results revealed that KLF8 may be a potential prognostic factor for pancreatic cancer.展开更多
目的:观察血小板源性生长因子BB(PDGF-BB)对血管平滑肌细胞(VSMCs)增殖及分化相关基因表达的影响,探讨其可能的机制。方法:分离体外培养的SD大鼠胸腹主动脉VSMCs,分为空白对照组和不同浓度PDGF-BB处理组。分别采用MTT法、流式细胞术和...目的:观察血小板源性生长因子BB(PDGF-BB)对血管平滑肌细胞(VSMCs)增殖及分化相关基因表达的影响,探讨其可能的机制。方法:分离体外培养的SD大鼠胸腹主动脉VSMCs,分为空白对照组和不同浓度PDGF-BB处理组。分别采用MTT法、流式细胞术和伤口愈合实验检测PDGF-BB对VSMCs增殖、细胞周期和迁移活性的影响;用W estern b lotting分析检测VSMCs表型标志物的表达;用免疫沉淀和免疫共沉淀分析检测Krüppel样因子4(KLF4)磷酸化及与其它转录因子的相互作用。结果:PDGF-BB促进VSMCs增殖和迁移;上调增殖相关蛋白PCNA的表达,下调增殖抑制蛋白p27、分化相关蛋白SM22α的表达。PDGF-BB诱导KLF4的表达和磷酸化,促进KLF4与NF-κB的相互作用,抑制KLF4与Sm ad3、HDAC2的结合。结论:PDGF-BB可能通过影响KLF4磷酸化及其与不同转录调节因子的相互作用而诱导VSMCs表型转化。展开更多
目的探讨乳腺癌组织中miRNA-92a、KLF4 mRNA的表达及与临床病理参数、预后的关系。方法选取2014年1月—2016年9月长沙市第一医院乳甲外科收治的124例乳腺癌患者。qRT-PCR检测癌组织和距离>5 cm的癌旁组织中miR-92a、KLF4 m RNA表达;P...目的探讨乳腺癌组织中miRNA-92a、KLF4 mRNA的表达及与临床病理参数、预后的关系。方法选取2014年1月—2016年9月长沙市第一医院乳甲外科收治的124例乳腺癌患者。qRT-PCR检测癌组织和距离>5 cm的癌旁组织中miR-92a、KLF4 m RNA表达;Pearson相关性分析乳腺癌组织中miR-92amRNA表达与KLF4 m RNA表达的相关性;绘制不同miR-92a、KLF4 mRNA表达乳腺癌患者的生存曲线;多因素Cox回归分析乳腺癌患者预后不良影响因素。结果癌组织miR-92a、KLF4 mRNA相对表达量高于癌旁组织(P<0.05)。Pearson相关性分析显示,乳腺癌组织中miR-92a与KLF4 mRNA表达呈正相关(r=0.612,P<0.05)。临床分期Ⅲ、Ⅳ期和有淋巴结转移患者的miR-92a、KLF4 mRNA表达水平高于临床分期Ⅰ、Ⅱ期和无淋巴结转移患者(P<0.05)。不同年龄、肿瘤直径、分化程度、雌激素受体、孕激素受体患者miR-92a、KLF4 mRNA相对表达量比较,差异无统计学意义(P>0.05)。miR-92a、KLF4 mRNA相对表达量高表达患者累积生存率低于低表达患者(P<0.05)。多因素Cox回归分析显示,临床分期Ⅲ、Ⅳ期[HR=3.716(95%CI:1.765,7.826)]、淋巴结转移[HR=3.021(95%CI:1.341,6.803)]、miR-92a≥1.627[HR=3.401(95%CI:1.358,8.515)]、KLF4 mRNA≥2.270[HR=2.059(95%CI:1.026,4.133)]是乳腺癌患者预后不良的危险因素(P<0.05)。结论乳腺癌组织中miR-92a、KLF4 m RNA高表达与临床分期、淋巴结转移有关,可能成为乳腺癌预后的标志物。展开更多
Krüppel样因子(Krüppel-like factors,KLFs)是一组与真核基因转录调控密切相关的锌指蛋白.KLFs高度保守的羧基末端含3个串联的Cys2His2型锌指结构,用于结合GC盒和CACCC盒等DNA序列.红细胞中特异表达的珠蛋白基因和许多红系调...Krüppel样因子(Krüppel-like factors,KLFs)是一组与真核基因转录调控密切相关的锌指蛋白.KLFs高度保守的羧基末端含3个串联的Cys2His2型锌指结构,用于结合GC盒和CACCC盒等DNA序列.红细胞中特异表达的珠蛋白基因和许多红系调控因子中都含有CACCC盒.已有研究发现,多个KLFs通过结合CACCC盒参与调控珠蛋白基因表达和红系分化,例如,KLF1通过结合β-珠蛋白启动子和位点控制区(locus control region,LCR),促进β-珠蛋白的表达、γ-向β-珠蛋白基因的转换和红系分化;KLF2、KLF11和KLF13分别促进ε-和γ-珠蛋白基因的表达;KLF4促进α-和γ-珠蛋白基因的表达;KLF3和KLF8则抑制ε-和γ-珠蛋白基因的表达.本文综述了KLFs调控珠蛋白基因表达和红系分化的研究进展.展开更多
基金Supported by Grants from National Basic Research Program of China,973 program,No.2010CB529704 and No.2012CB910404National Natural Science Foundation of China,No.30800587,No.30971521,and No.31171338+1 种基金the Science and Technology Commission of Shanghai Municipality,No.11DZ2260300a scholar of the Shanghai Rising-Star Program from Science and Technology Commission of Shanghai Municipality,No.09QA1401900 to Wang P
文摘Krüppel-like factor(KLF) family proteins are transcription factors that regulate numerous cellular functions, such as cell proliferation, differentiation, and cell death. Posttranslational modification of KLF proteins is important for their transcriptional activities and biological functions. One KLF family member with important roles in cell proliferation and tumorigenesis is KLF5. The function of KLF5 is tightly controlled by post-translational modifications, including SUMOylation, phosphorylation, and ubiquitination. Recent studies from our lab and others' have demonstrated that the tumor suppressor FBW7 is an essential E3 ubiquitin ligase that targets KLF5 for ubiquitination and degradation. KLF5 contains functional Cdc4 phospho-degrons(CPDs), which are required for its interaction with FBW7. Mutation of CPDs in KLF5 blocks the ubiquitination and degradation of KLF5 by FBW7. The protein kinase Glycogen synthase kinase 3β is involved in the phosphorylation of KLF5 CPDs. In both cancer cell lines and mousemodels, it has been shown that FBW7 regulates the expression of KLF5 target genes through the modulation of KLF5 stability. In this review, we summarize the current progress on delineating FBW7-mediated KLF5 ubiquitination and degradation.
文摘Sp1/Krüppel样因子(Sp1-like and Krüppel-like factors,Sp1/KLFs)是一组与真核细胞转录调控密切相关的锌指蛋白。Sp1/KLFs的羧基末端高度保守,含有3个串联的Cys2His2锌指结构,用于结合DNA;其氨基末端在不同的家族成员间存在较大差异,主要是通过结合辅助因子发挥转录调控作用。Sp1/KLFs的表达具有组织、细胞分布以及发育时期的特异性,它们通过调控多种富含GC或CACCC的启动子的基因的表达,参与细胞增殖、分化、凋亡和肿瘤发生、发展等多种生理、病理过程。文章综述了Sp1/KLFs的结构特征、作用机制及生物学功能。
基金This study was supported by the National Natural Science Foundation of China，China Health Industry Research and Special Fund
文摘Background Pancreatic cancer is a lethal disease that is often diagnosed at an advanced stage.There is a lack of information to predict the prognosis of pancreatic cancer.Krüppel-like factor （KLF） 8 has been found to be deregulated in multiple cancers,and its high expression was correlated with poor prognosis.However,so far,no information was reported about the expression of KLF8 in pancreatic cancer.In the present study,we investigated,possibly for the first time,the expression of KLF8 in pancreatic cancer samples and analyzed its correlation with clinical parameters and overall survival （OS） rate.Methods We used immunohistochemical staining to detect KLF8 in 68 samples from patients who underwent surgery and its correlation with the clinicopathological characteristics.We used Kaplan-Meier curve to analyze the relationship between KLF8 expression and the OS time.Univariate analysis was performed in addition to multivariate hazard models with clinicopathological features to assess KLF8 as an independent prognostic factor.Results KLF8 was present in the cytoplasm of pancreatic cancer cells and 52.9％ of the 68 cases had positive expression.KLF8 expression was not associated with sex,age,tumor location,lymph node stage,and metastasis stage,but was associated with tumor stage （P=0.04）.Kaplan-Meier method demonstrated that patients with negative expression of KLF8 had a better prognosis.In univariate and multivariate models,KLF8 was a significant predictor of OS in pancreatic cancer.Conclusion Our results revealed that KLF8 may be a potential prognostic factor for pancreatic cancer.
文摘目的:观察血小板源性生长因子BB(PDGF-BB)对血管平滑肌细胞(VSMCs)增殖及分化相关基因表达的影响,探讨其可能的机制。方法:分离体外培养的SD大鼠胸腹主动脉VSMCs,分为空白对照组和不同浓度PDGF-BB处理组。分别采用MTT法、流式细胞术和伤口愈合实验检测PDGF-BB对VSMCs增殖、细胞周期和迁移活性的影响;用W estern b lotting分析检测VSMCs表型标志物的表达;用免疫沉淀和免疫共沉淀分析检测Krüppel样因子4(KLF4)磷酸化及与其它转录因子的相互作用。结果:PDGF-BB促进VSMCs增殖和迁移;上调增殖相关蛋白PCNA的表达,下调增殖抑制蛋白p27、分化相关蛋白SM22α的表达。PDGF-BB诱导KLF4的表达和磷酸化,促进KLF4与NF-κB的相互作用,抑制KLF4与Sm ad3、HDAC2的结合。结论:PDGF-BB可能通过影响KLF4磷酸化及其与不同转录调节因子的相互作用而诱导VSMCs表型转化。
文摘Krüppel样因子(Krüppel-like factors,KLFs)是一组与真核基因转录调控密切相关的锌指蛋白.KLFs高度保守的羧基末端含3个串联的Cys2His2型锌指结构,用于结合GC盒和CACCC盒等DNA序列.红细胞中特异表达的珠蛋白基因和许多红系调控因子中都含有CACCC盒.已有研究发现,多个KLFs通过结合CACCC盒参与调控珠蛋白基因表达和红系分化,例如,KLF1通过结合β-珠蛋白启动子和位点控制区(locus control region,LCR),促进β-珠蛋白的表达、γ-向β-珠蛋白基因的转换和红系分化;KLF2、KLF11和KLF13分别促进ε-和γ-珠蛋白基因的表达;KLF4促进α-和γ-珠蛋白基因的表达;KLF3和KLF8则抑制ε-和γ-珠蛋白基因的表达.本文综述了KLFs调控珠蛋白基因表达和红系分化的研究进展.
