关键词： 宫颈癌组织   激活的白激酶C受体1   IQ序列三磷酸鸟苷酶激活蛋白   病理特征   β-连环蛋白   相关性  

摘要： 目的:分析宫颈癌组织中激活的白激酶C受体1(RACK1)、IQ序列三磷酸鸟苷酶激活蛋白(IQGAPl)表达及与临床病理特征和β-连环蛋白(β-catenin)的相关性。方法:收集2018年1月-2020年12月本院行宫颈癌手术治疗的患者106例临床资料,采用实时荧光定量PCR(RT-PCR)和免疫组化技术检测RACK1、IQGAP1、β-catenin mRNA和蛋白表达,分析宫颈癌组织中RACK1、IQGAP1表达及与临床病理特征和β-catenin的相关性。结果:宫颈癌组织中RACK1 mRNA的相对表达量(0.27±0.11)低于癌旁组织(0.75±0.19),IQGAP1 mRNA(0.65±0.18)、β-catenin mRNA(0.61±0.21)高于癌旁组织(0.22±0.13、0.32±0.17),RACK1蛋白阳性率(18.9%)低于癌旁组织(63.2%),IQGAP1(76.4%)、β-catenin(68.9%)蛋白阳性率高于癌旁组织(28.3%、31.1%)(均P<0.05)。RACK1在高分化、TNM分期为I期、无淋巴结转移的宫颈癌组织中阳性率高于中低分化、TNM分期为II-III期、有淋巴结转移患者的组织,IQGAP1在中低分化、TNM分期为II-III期的宫颈癌组织中阳性率高于高分化、TNM分期为I期组织(均P<0.05)。宫颈癌中RACK1表达与β-catenin呈负相关(r=-0.405,P<0.05),IQGAP1表达与β-catenin呈显著正相关(r=0.346,P<0.05)。结论:宫颈癌组织RACK1低表达,IQGAP1高表达;RACK1蛋白表达异常可能与患者宫颈癌分化程度、TNM分期、淋巴结转移及β-catenin表达有关,IQGAP1蛋白表达异常可能与分化程度、TNM分期及β-catenin表达有关。

关键词： IQGAP1   EGF   EGFR   PD-L1   Cancer   IQGAP1   EGF   EGFR   PD-L1   Cancer  

摘要： IQ motif containing GTPase activating protein 1 (IQGAP1) is a scaffold protein to transduce multiple signals from the extracellular microenvironment. However, whether IQGAP1 mediates EGF-induced cancer progression has been not observed. In this research, we explored the immunological correlations of IQGAP1. IQGAP1 was upregulated in most cancer and related to poor prognosis in ovarian cancer. In addition, IQGAP1 was correlated with immune-related genes and tumor-infiltrating lymphocytes. IQGAP1 was a novel EGF-response gene, which was up-regulated by EGF. As the downstream of EGFR, IQGAP1 mediated EGF-induced proliferation, migration and invasion of tumor cells and was essential for EGF-induced PD-L1 expression as well. Mechanically, IQGAP1 interacted with STATs and mediated their phosphorylation. Furthermore, Curcumin inhibited EGFR/IQGAP1 axis to down-regulate PD-L1 and suppress cancer progression. To sum up, IQGAP1 responds to EGF stimulation and mediates EGF-induced phosphorylation of STATs, which is a novel promising target for blocking the EGFinduced cancer progression.

关键词： human Fas-associated factor 1(FAF1)   heat shock protein 70(Hsp70)   adherens junction   RhoA activation   IQGAP1   X-ray crystallography   FAF1–Hsp70 complex  

摘要： Fas-associated factor 1 (FAF1) is a scaffolding protein that plays multiple functions, and dysregulation of FAF1 is associated withmany types of diseases such as cancers. FAF1 contains multiple ubiquitin-related domains (UBA, UBL1, UBL2, UAS, and UBX), eachdomain interacting with a specific partner. In particular, the interaction of UBL1 with heat shock protein 70 (Hsp70) is associatedwith tumor formation, although the molecular understanding remains unknown. In this study, the structural analysis revealed thatHis160 of FAF1 is important for its interaction with Hsp70. The association of Hsp70 with FAF1 is required for the interaction withIQGAP1. FAF1 negatively regulates RhoA activation by FAF1–Hsp70 complex formation, which then interacts with IQGAP1. Thesesteps play a key role in maintaining the stability of cell-to-cell junction. We conclude that FAF1 plays a critical role in the structureand function of adherens junction during tissue homeostasis and morphogenesis by suppressing RhoA activation, which induces theactivation of Rho-associated protein kinase, phosphorylation of myosin light chain, formation of actin stress fiber, and disruptionof adherens junction. In addition, depletion of FAF1 increased collective invasion in a 3D spheroid cell culture. These results provideinsightinto how the FAF1–Hsp70 complex acts as a novelregulator ofthe adherens junction integrity. The complex can be a potentialtherapeutic target to inhibit tumorigenesis and metastasis.

关键词： IQGAP1   MMP2   Invasion   NF-kappa B  

摘要： Esophageal squamous cell carcinoma (ESCC) is one type of the most common malignancies, yet the overall survival rate is still not ideal. IQ motif containing GTPase activating protein 1 (IQGAP1) participates in cell biological functions of various tumors as an oncogene. However, the mechanisms of IQGAP1 affecting malignant development of ESCC are still unclear. In this study, the expression and correlation of IQGAP1 and MMP2 in esophageal cancer tissues were evaluated by online databases and immunohistochemistry. Stably transfected cell lines with IQGAP1 overexpression and knockdown were constructed. Cell growth, migration and invasion ability, the expression of MMP2 and NF-kappa B expression were examined in ESCC cells. Furthermore, the cellular malignant phenotypes of ESCC and MMP2 expression in IQGAP1 overexpressing cells after treatment with the NF-kappa B inhibitor pyrrolidinecarbodithioic acid (PDTC) or JSH-23 were detected. We found that the expression of IQGAP1 and MMP2 were up-regulated and positively correlated in ESCC tissues. IQGAP1 overexpression promoted the growth, migration and invasion of ESCC cells, and up-regulated the expression of MMP2, and increased the expression and the nuclear localization level of NF-kappa B. Treating with PDTC or JSH-23 reversed IQGAP1-mediated cell migration and invasion ability, as well as the expression of MMP2. In summary, IQGAP1 plays a tumor promotion role to regulate the migration and invasion of ESCC cells and the expression of MMP2 through upregulating NF-kappa B activity, supporting a promising therapeutic target against ESCC.

关键词： IQGAP1   sphingosine 1-phosphate receptor 3   bone marrow mesenchymal stromal cells   migration   liver fibrosis   Cdc42   Rac1   F-actin  

摘要： IQ motif-containing guanosine triphosphatase (GTPase)-activating protein 1 (IQGAP1) is a cytosolic scaffolding protein involved in cell migration. Our previous studies suggest sphingosine 1-phosphate (S1P) triggers bone marrow (BM) mesenchymal stromal cells (BMSCs) to damaged liver, thereby promoting liver fibrosis. However, the role of IQGAP1 in S1P-induced BMSC migration and liver fibrogenesis remains unclear. Chimeric mice of BM cell labeled by EGFP were used to build methionine-choline-deficient and high-fat (MCDHF)-diet-induced mouse liver fibrosis. IQGAP1 small interfering RNA (siRNA) was utilized to silence IQGAP1 in vivo. IQGAP1 expression is significantly elevated in MCDHF-diet-induced mouse fibrotic livers. Positive correlations are presented between IQGAP1 and fibrosis hallmarks expressions in human and mouse fibrotic livers. In vitro, depressing IQGAP1 expression blocks S1P-induced motility and cytoskeleton remodeling of BMSCs. S1P facilitates IQGAP1 aggregating to plasma membrane via S1P receptor 3 (S1PR(3)) and Cdc42/Rac1. In addition, IQGAP1 binds to Cdc42/Rac1, regulating S1P-induced activation of Cdc42/Rac1 and mediating BMSC migration in concert. In vivo, silencing IQGAP1 reduces the recruitment of BMSCs to impaired liver and effectively alleviates liver fibrosis induced by MCDHF diet. Together, silencing IQGAP1 relieves liver fibrosis by blocking BMSC migration, providing an effective therapeutic strategy for liver fibrosis.

摘要： IQGAP1 is a multidomain scaffold protein that coordinates the direction and impact of multiple signaling pathways by scaffolding its various binding partners. However, the spatial and temporal resolution of IQGAP1 scaffolding remains unclear. Here, we use fluorescence imaging and correlation methods that allow for real-time live-cell changes in IQGAP1 localization and complex formation during signaling. We find that IQGAP1 and PIPKI gamma interact on both the plasma membrane and in cytosol. Epidermal growth factor (EGF) stimulation, which can initiate cytoskeletal changes, drives the movement of the cytosolic pool toward the plasma membrane to promote cytoskeletal changes. We also observe that a significant population of cytosolic IQGAP1-PIPKI gamma complexes localize to early endosomes, and in some instances form aggregated clusters which become highly mobile upon EGF stimulation. Our imaging studies show that PIPKI gamma and PI3K bind simultaneously to IQGAP1, which may accelerate conversion of PI4P to PI(3,4,5)P-3 that is required for cytoskeletal changes. Additionally, we find that IQGAP1 is responsible for PIPKI gamma association with two proteins associated with cytoskeletal changes, talin and Cdc42, during EGF stimulation. These results directly show that IQGAP1 provides a physical link between phosphoinositides (through PIPKI gamma), focal adhesion formation (through talin), and cytoskeletal reorganization (through Cdc42) upon EGF stimulation. Taken together, our results support the importance of IQGAP1 in regulating cell migration by linking phosphoinositide lipid signaling with cytoskeletal reorganization.

关键词： fibrosis   foreign body response   inflammation   mechanotransduction  

摘要： The aim of this study was to further elucidate the molecular mechanisms that mediate pathologic foreign body response (FBR) to biomedical implants. The longevity of biomedical implants is limited by the FBR, which leads to implant failure and patient morbidity. Since the specific molecular mechanisms underlying fibrotic responses to biomedical implants have yet to be fully described, there are currently no targeted approaches to reduce pathologic FBR. We utilized proteomics analysis of human FBR samples to identify potential molecular targets for therapeutic inhibition of FBR. We then employed a murine model of FBR to further evaluate the role of this potential target. We performed histological and immunohistochemical analysis on the murine FBR capsule tissue, as well as single-cell RNA sequencing (scRNA-seq) on cells isolated from the capsules. We identified IQ motif containing GTPase activating protein 1 (IQGAP1) as the most promising of several targets, serving as a central molecular mediator in human and murine FBR compared to control subcutaneous tissue. IQGAP1-deficient mice displayed a significantly reduced FBR compared to wild-type mice as evidenced by lower levels of collagen deposition and maturity. Our scRNA-seq analysis revealed that decreasing IQGAP1 resulted in diminished transcription of mechanotransduction, inflammation, and fibrosis-related genes, which was confirmed on the protein level with immunofluorescent staining. The deficiency of IQGAP1 significantly attenuates FBR by deactivating downstream mechanotransduction signaling, inflammation, and fibrotic pathways. IQGAP1 may be a promising target for rational therapeutic design to mitigate pathologic FBR around biomedical implants.

关键词： AmotL2   IQGAP1   and FKBP51   angiogenesis   glioblastoma stem cells   scaffold proteins   stem cell niche   stemness   tumor heterogeneity   tumor immune infiltrate   tumor microenvironment  

摘要： Glioma stem cells (GSCs) live in a continuous process of stemness reprogramming to achieve specific cell commitment within the so-called GSC niches, specifically located in periarteriolar regions. In this review, we analyze the expression levels, cellular and subcellular location, and role of three scaffold proteins (IQGAP1, FKBP51, and AmotL2) in GSC niches. Scaffold proteins contribute to cell differentiation, migration, and angiogenesis in glioblastoma. It could be of diagnostic interest for establishing stages, for therapeutic targets, and for improving glioblastoma prognosis, which is still at the experimental level.

关键词： 垂体腺瘤   侵袭性   circ-IQGAP1   circ-ZNF79   JAK2   STAT3  

摘要： 目的:本研究基于垂体腺瘤高通量测序结果,筛选侵袭性垂体腺瘤相关基因circ-IQGAP1、circ-ZNF79,检测circ-IQGAP1、circ-ZNF79及肿瘤热门通路蛋白JAK2、STAT3在垂体腺瘤中的表达情况,剖析目的基因与JAK2/STAT3通路对垂体腺瘤侵袭性的影响,探索与垂体腺瘤侵袭性生物学行为相关的潜在生物标志物,为寻找有助于垂体腺瘤早期诊断、治疗及预后评估的新方法做一些有益的工作。方法:本课题自2020年06月至2021年03月期间于河北大学附属医院神经外科收集共计27例因无功能性垂体腺瘤(根据术前实验室检查及术后病理结果诊断)行神经内镜辅助下经鼻-蝶入路垂体腺瘤切除术的患者的垂体腺瘤组织样本(黄豆大小)。根据术前影像学检查提示,27例垂体腺瘤患者中有侵袭性垂体腺瘤患者12例,非侵袭性垂体腺瘤患者15例,采用随机数字法各纳入8例进行研究,若后期经总RNA质检不合格,再随机从剩余样本中增补。所有患者术前均未行相关手术、放化疗等其它治疗。按照垂体腺瘤的侵袭性与否,将所取的16例垂体腺瘤组织样本进行分组,其中8例侵袭性垂体腺瘤样本作为侵袭组(实验组),8例非侵袭性垂体腺瘤样本作为非侵袭组(对照组)。采用实时荧光定量PCR法(RT-PCR)检测circ-IQGAP1、circ-ZNF79在实验组和对照组垂体腺瘤组织中的相对表达情况,免疫组织化学染色方法(IHC)检测通路蛋白JAK2、STAT3在实验组和对照组垂体腺瘤组织中的相对表达情况。整理数据结果并进行统计学处理,分析目的基因、蛋白在实验组和对照组中表达的差异性,得出结论,上述研究方案经过河北大学附属医院伦理委员会批准实施。结果:1.侵袭组中circ-IQGAP1相对表达水平(0.96±0.51)显著低于非侵袭性组(2.12±0.72),(P<0.05)。2.侵袭组中circ-ZNF79相对表达水平(3.19±0.87)显著高于非侵袭组(1.34±0.71),(P<0.05)。3.侵袭性垂体腺瘤组织样本中JAK2高表达4例,表达率为50.0%;非侵袭性垂体腺瘤组织样本中JAK2高表达1例,表达率为12.5%。两组样本表达强度存在差异,侵袭性组比非侵袭性组表达强度显著增强(Z=-4.424 P<0.05)。4.侵袭性垂体腺瘤组织样本中STAT3高表达3例,表达率为37.5%;非侵袭性垂体腺瘤组织样本中STAT3高表达1例,表达率为12.5%。两组样本表达强度存在差异,侵袭性组比非侵袭性组表达强度显著增强(Z=-3.682 P<0.05)。5.在垂体腺瘤中,随着JAK2的表达水平上调,STAT3也随之上调。JAK2与ATAT3两者表达呈正相关(r=0.313 P<0.001),差异有统计学意义。结论:***-IQGAP1、circ-ZNF79、JAK2及STAT3在侵袭性垂体腺瘤和非侵袭性垂体腺瘤中均有表达。***-IQGAP1在侵袭性垂体腺瘤中相对表达水平显著低于非侵袭性垂体腺瘤,因此circ-IQGAP1可能抑制了垂体腺瘤侵袭性行为的发生。***-ZNF79在侵袭性垂体腺瘤中相对表达水平显著高于非侵袭性垂体腺瘤,因此circ-ZNF79可能促进了垂体腺瘤侵袭性行为的发生。4.与非侵袭性垂体腺瘤相比,JAK2、STAT3在侵袭性垂体腺瘤中表达强度明显增强,且表达水平呈正相关,因此JAK2/STAT3信号通路的激活可能促进了垂体腺瘤侵袭性行为的发生。

关键词： IQGAP1   脓毒症   PI3K/Akt信号通路   THP-1   CLP  

摘要： 背景:脓毒症(sepsis)是临床常见急危重症之一,死亡率高,尽管近年来脓毒症的综合治疗已取得重要进展,但病死率仍高达30%-70%。对脓毒症的防治及机制研究在不断进展,但脓毒症的防治至今仍是世界性的难题,是临床急需解决的问题。磷脂酰肌醇-3-激酶/蛋白激酶B(Phosphatidylinositol 3 kinase/Protein kinase B,PI3K/Akt)是一条经典信号通路,其在脓毒症的发生发展中发挥着重要作用,如参与调控炎症因子的表达及免疫调节。先前研究表明,PI3K/Akt信号通路参与脓毒症关键炎症因子的表达,许多研究也表明,抑制PI3K/Akt信号通路能减轻炎症反应。在对前人的研究总结中,我们发现一个问题:PI3K/Akt被激活是从病原体感染细胞到胞内信号转导、炎症因子释放这整个过程中的相对较晚的事件,而对信号通路下游分子的追逐难以把握炎症反应始动机制及防治的靶点,此时可能干预效果差。因此,寻找处于上游即炎症反应早期的激活因素至关重要。含有IQ基序的三磷酸鸟苷酶激活蛋白-1(IQ motif containing GTPase activating protein 1,IQGAP1)是一种支架蛋白,它参与多种信号通路。2016年一项关于癌细胞的研究表明,IQGAP1参与PI3K/Akt信号通路中关键前体的合成,并详细演绎IQGAP1支架蛋白的特性,通过结合组成具有协调性的多酶复合体,把I型磷脂酰肌醇磷酸激酶(Phosphatidylinositol phosphokinase type I,PIPKI)和PI3K依次安放到相近的功能位依次合成磷脂酰肌醇-4,5-二磷酸(phosphatidylinosito-4,5-bisphosphate,PIP2)和磷脂酰肌醇-3,4,5-三磷酸(Phosphatidylinositol-3,4,5-triphosphate,PIP3),并激活Akt。然而,其对炎症状态下PI3K/Akt信号传导途径的作用和对炎症因子释放的影响尚不清楚。方法:1.应用LPS刺激THP-1细胞,Western blot技术检测0h、2h、4h、6h、12h、24h IQGAP1的表达,PI3K/Akt信号通路关键蛋白的活化,以及炎症因子肿瘤坏死因2.子-α、白介素-1β和IL-6的表达水平。3.应用IQGAP1的短发夹核糖核酸慢病毒转染THP-1细胞,并用RT-PCR检测IQGAP1m RNA转录水平、Western blot检测IQGAP1蛋白表达以鉴定转染效果,观察沉默IQGAP1表达对LPS刺激THP-1细胞PI3K/Akt信号通路蛋白分子表达、活化以及炎症因子TNF-α、IL-1β和IL-6表达的影响。4.为证实PI3K/Akt信号通路对炎症反应的调控作用,应用PI3K抑制剂LY294002及Akt抑制剂MK2206分别抑制PI3K/Akt信号通路并验证效果后观察TNF-α、IL-1β和IL-6表达水平的变化。5.雄性C57小鼠随机分为假手术组(Shams组,开腹后仅游离暴露盲肠后还纳关腹)、脓毒症组(CLP组,开腹后游离盲肠,采用CLP法构造脓毒症模型小鼠)、溶剂注射对照组(Vehicle组,使用PBS鼠尾静脉注射)和慢病毒鼠尾静脉注射治疗组(LV 10μL、LV 30μL、LV 50μL)。于术后24h处死各组小鼠并收集血清和肝脏组织。采用HE染色观察肝脏病理损伤情况;Elisa法检测血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)和炎症因子水平;RT-q PCR检测肝脏组织中炎症因子基因表达水平;Western blot检测各组动物PI3K/Akt通路表达情况;免疫组化法观察肝脏组织中髓过氧化物酶(Myeloperoxidase,MPO)、IL-6、IL-1β表达情况。6.使用F4/80标记小鼠肝脏巨噬细胞,观察各组动物术后24h肝脏巨噬细胞浸润情况,并使用Western blot检测各组动物凋亡相关蛋白表达情况;使用CD31/Tunel免疫荧光染色共标观察各组动物内皮细胞调亡情况。结果:1.与对照组相比,LPS刺激THP-1细胞TNF-α、IL-1β和IL-6分泌增加。2.慢病毒转染IQGAP1m RNA及IQGAP1蛋白表达显著下降;沉默IQGAP1表达后,与LPS组相比,LPS刺激的THP-1细胞中PI3K/Akt信号通路关键蛋白表达下降,TNF-α、IL-1β和IL-6水平显著降低。***3K抑制剂LY294002或Akt抑制剂MK2206抑制TNF-α、IL-1β和IL-6的产生。产生TNF-α、IL-1β和IL-6的重要信号通路PI3K/Akt受IQGAP1的影响:沉默IQGAP1的表达有效抑制LPS刺激的THP-1细胞中PI3K和Akt的磷酸化,从而抑制TN