R-spondin2(Rspo2)是蛋白质家族RSPOs成员之一,其可以通过富含亮氨酸重复序列的G蛋白偶联受体4/5(leucine-rich repeat-containing G protein-coupled receptor 4/5,LGR4/5)、细胞表面跨膜E3泛素连接酶ZNRF3/RNF43(zinc and ring finger...R-spondin2(Rspo2)是蛋白质家族RSPOs成员之一,其可以通过富含亮氨酸重复序列的G蛋白偶联受体4/5(leucine-rich repeat-containing G protein-coupled receptor 4/5,LGR4/5)、细胞表面跨膜E3泛素连接酶ZNRF3/RNF43(zinc and ring finger 3/ring finger protein 43)、硫酸乙酰肝素蛋白聚糖(heparan sulfate proteoglycans,HSPGs)和含GTP酶激活蛋白质1的IQ基序(IQ motif-containing GTPase-activating protein 1,IQGAP1)来调控Wnt/β连环蛋白(catenin)信号通路,Wnt/β-catenin信号通路是目前研究最广泛且与基础骨生物学直接相关的信号通路,该通路中任何一环节出现问题都可能对骨的调控产生影响。近年来研究发现,Rspo2可以通过Wnt/β-catenin对成骨细胞(osteoblast,OB)、破骨细胞(osteoclast,OC)和软骨细胞产生作用,并参与一些骨骼疾病如脊柱后纵韧带骨化(ossification of the posterior longitudinal ligament,OPLL)、骨关节炎(osteoarthritis,OA)和类风湿性关节炎(rheumatoid arthritis,RA)的发生发展,因此对Rspo2的研究可能会成为骨相关疾病新的治疗方向。本文结合最新研究进展,就Rspo2的结构和主要功能、Rspo2调控Wnt/β-catenin信号通路的相关机制及其对骨骼系统的影响作一综述,以期为骨相关疾病的防治提供新的思路和途径。展开更多
The R-spondin family of proteins are Wnt agonists, and the complete embryonic disruption of Rspo2 results in skeletal developmental defects that recapitulate the phenotype observed with Lrp5/6 deficiency. Previous wor...The R-spondin family of proteins are Wnt agonists, and the complete embryonic disruption of Rspo2 results in skeletal developmental defects that recapitulate the phenotype observed with Lrp5/6 deficiency. Previous work has shown that R-spondin-2(Rspo2, RSPO2) is both highly expressed in Wnt-stimulated pre-osteoblasts and its overexpression induces osteoblast differentiation in the same cells, supporting its putative role as a positive autocrine regulator of osteoblastogenesis. However, the role of Rspo2 in regulating osteoblastogenesis and bone formation in postnatal bone has not been explored. Here we show that limb-bud progenitor cells from Rspo2 knockout mice undergo reduced mineralization during osteoblastogenesis in vitro and have a corresponding alteration in their osteogenic gene expression profile. We also generated the first Rspo2 conditional knockout(Rspo2 floxed) mouse and disrupted Rspo2 expression in osteoblast-lineage cells by crossing to the Osteocalcin-Cre mouse line(OcnCre + Rspo2 ^(f/f)). Ocn-Cre + Rspo2 f/fmale and female mice at 1, 3, and 6 months were examined. Ocn-Cre + Rspo2 f/fmice are decreased in overall body size compared to their control littermates and have decreased bone mass. Histomorphometric analysis of1-month-old mice revealed a similar number of osteoblasts and mineralizing surface per bone surface with a simultaneous decrease in mineral apposition and bone formation rates. Consistent with this observation, serum osteocalcin in 3-month-old Ocn-Cre +Rspo2 f/fwas reduced, and bone marrow-mesenchymal stem cells from Ocn-Cre + Rspo2 f/fmice undergo less mineralization in vitro.Finally, gene expression analysis and immunohistochemistry of mature bone shows reduced beta-catenin signaling in Ocn-Cre +Rspo2 f/f. Overall, RSPO2 reduces osteoblastogenesis and mineralization, leading to reduced bone mass.展开更多
背景与目的:结直肠癌的发生、发展涉及多个癌基因的激活和抑癌基因的失活,野生型R-脊椎蛋白3(R-spondin 3,RSPO3)在结直肠癌生长中的作用目前尚不清楚,本研究旨在探讨RSPO3对结直肠癌生长的影响并探索其潜在机制。方法:采用生物信息学分...背景与目的:结直肠癌的发生、发展涉及多个癌基因的激活和抑癌基因的失活,野生型R-脊椎蛋白3(R-spondin 3,RSPO3)在结直肠癌生长中的作用目前尚不清楚,本研究旨在探讨RSPO3对结直肠癌生长的影响并探索其潜在机制。方法:采用生物信息学分析RSPO3在结直肠癌及泛癌组织中的表达,分析结直肠癌中RSPO3表达与自然杀伤(natural killer,NK)细胞浸润、NK细胞激活分子表达的相关性。利用短发夹RNA(short hairpin RNA,shRNA)和慢病毒感染建立RSPO3敲减的SW480-RSPO3-KD细胞株、RSPO3过表达的HCT116-RSPO3-OE细胞株及相应的对照细胞株。采用细胞计数试剂盒-8(cell counting kit-8,CCK-8)检测体外各稳定转染细胞株的细胞增殖。采用流式细胞术分析各稳定转染细胞株的细胞周期、裸小鼠脾脏和移植瘤组织中NK细胞的比例。通过裸小鼠皮下移植瘤模型观察RSPO3敲减或过表达的结肠癌细胞在裸小鼠体内的生长。利用双荧光素酶报告基因系统检测RSPO3敲减或过表达对结肠癌Wnt基因转录活性的影响。结果:生物信息学分析显示,RSPO3在多种实体瘤肿瘤组织包括结直肠癌组织中的表达显著低于相应的癌旁组织。RSPO3敲减或过表达不影响体外SW480和HCT116结肠癌细胞的增殖(P>0.05)和细胞周期(P>0.05)。但在裸小鼠体内,与对照细胞相比,RSPO3敲减显著促进SW480细胞移植瘤的生长(260.2±162.4 vs 1311.7±570.1,P<0.05),而RSPO3过表达则显著抑制HCT116细胞移植瘤的生长(1549.0±241.2 vs 512.1±250.0,P<0.05)。流式细胞术分析发现,在荷移植瘤裸小鼠体内,RSPO3敲减显著减少了脾脏和移植瘤组织中NK细胞的比例(脾脏:6.42±0.94 vs 5.25±0.59,P=0.04;移植瘤:8.27±0.29 vs 6.48±1.48,P=0.04);而RSPO3过表达显著增加了脾脏和移植瘤组织中NK细胞的比例(脾脏:5.29±0.16 vs 7.02±0.49,P=0.01;移植瘤:6.39±0.39 vs 8.14±0.34,P<0.05)。癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据相关性分析显示,RSPO3表达与NK细胞表面标志物CD56(r=0.58,P<0.05)和CD16(r=0.64,P<0.05)的表达显著正相关,并与NK细胞激活标志物CD69(r=0.51,P<0.05)和KLRB1(r=0.37,P<0.05)的表达显著正相关。双荧光素酶报告基因实验结果显示,RSPO3敲减后Wnt荧光素酶活性下调(1.0±0.0 vs 0.45±0.09,P<0.05),而RSPO3过表达后Wnt荧光素酶活性上调(1.0±0.0 vs 1.75±0.14,P<0.05)。结论:RSPO3能在体内显著抑制结直肠癌移植瘤的生长,并能增加移植瘤组织中NK细胞浸润,RSPO3是一个潜在的结直肠癌的抑制基因。展开更多
R-spondins are secretory proteins localized in the endoplasmic reticulum and Golgi bodies and are processed through the secretory pathway.Among the R-spondin family,RSPO2 has emanated as a novel regulator of Wnt signa...R-spondins are secretory proteins localized in the endoplasmic reticulum and Golgi bodies and are processed through the secretory pathway.Among the R-spondin family,RSPO2 has emanated as a novel regulator of Wnt signaling,which has now been acknowledged in numerous in vitro and in vivo studies.Cancer is an abnormal growth of cells that proliferates and spreads uncontrollably due to the accumulation of genetic and epigenetic factors that constitutively activate Wnt signaling in various types of cancer.Colorectal cancer (CRC) begins when cells in the colon and rectum follow an indefinite pattern of division due to aberrant Wnt activation as one of the key hallmarks.Decades-long progress in research on R-spondins has demonstrated their oncogenic function in distinct cancer types,particularly CRC.As a critical regulator of the Wnt pathway,it modulates several phenotypes of cells,such as cell proliferation,invasion,migration,and cancer stem cell properties.Recently,RSPO mutations,gene rearrangements,fusions,copy number alterations,and altered gene expression have also been identified in a variety of cancers,including CRC.In this review,we addressed the recent updates regarding the recurrently altered R-spondins with special emphasis on the RSPO2 gene and its involvement in potentiating Wnt signaling in CRC.In addition to the compelling physiological and biological roles in cellular fate and regulation,we propose that RSPO2 would be valuable as a potential biomarker for prognostic,diagnostic,and therapeutic use in CRC.展开更多
Alveolar macrophages(AMs)are self-maintained immune cells that play vital roles in lung homeostasis and immunity.Although reporter mice and culture systems have been established for studying macrophages,an accurate an...Alveolar macrophages(AMs)are self-maintained immune cells that play vital roles in lung homeostasis and immunity.Although reporter mice and culture systems have been established for studying macrophages,an accurate and specific reporter line for alveolar macrophage study is still not available.Here we reported a novel Rspo1-tdTomato gene reporter mouse line that could specifically label mouse AMs in a cell-intrinsic manner.Using this reporter system,we visualized the dynamics of alveolar macrophages intravitally under steady state and characterized the alveolar macrophage differentiation under in vitro condition.By performing ATAC-seq,we found that insertion of the tdTomato cassette in the Rspo1 locus increased the accessibility of a PPARE motif within the Rspo1 locus and revealed a potential regulation by key transcription factor PPAR-γfor alveolar macrophage differentiation in vitro and in vivo.Consistently,perturbation of PPAR-γby its agonist rosiglitazone or inhibitor GW9662 resulted in corresponding alteration of tdTomato expression in alveolar macrophages together with the transcription of PPAR-γdownstream target genes.Furthermore,global transcriptomic analyses of AMs from the wild type mice and the Rspo1-tdTomato mice showed comparable gene expression profiles,especially those AM-specific genes,confirming that the insertion of the tdTomato cassette in the Rspo1 locus does not impact the cell identity and biological function of AMs under normal condition.Taken together,our study provides an alternative tool for in vivo and in vitro labeling of alveolar macrophages with high specificity which could also be utilized as an indicator of PPAR-γactivity for future development of PPAR-γspecific targeting drugs.展开更多
文摘R-spondin2(Rspo2)是蛋白质家族RSPOs成员之一,其可以通过富含亮氨酸重复序列的G蛋白偶联受体4/5(leucine-rich repeat-containing G protein-coupled receptor 4/5,LGR4/5)、细胞表面跨膜E3泛素连接酶ZNRF3/RNF43(zinc and ring finger 3/ring finger protein 43)、硫酸乙酰肝素蛋白聚糖(heparan sulfate proteoglycans,HSPGs)和含GTP酶激活蛋白质1的IQ基序(IQ motif-containing GTPase-activating protein 1,IQGAP1)来调控Wnt/β连环蛋白(catenin)信号通路,Wnt/β-catenin信号通路是目前研究最广泛且与基础骨生物学直接相关的信号通路,该通路中任何一环节出现问题都可能对骨的调控产生影响。近年来研究发现,Rspo2可以通过Wnt/β-catenin对成骨细胞(osteoblast,OB)、破骨细胞(osteoclast,OC)和软骨细胞产生作用,并参与一些骨骼疾病如脊柱后纵韧带骨化(ossification of the posterior longitudinal ligament,OPLL)、骨关节炎(osteoarthritis,OA)和类风湿性关节炎(rheumatoid arthritis,RA)的发生发展,因此对Rspo2的研究可能会成为骨相关疾病新的治疗方向。本文结合最新研究进展,就Rspo2的结构和主要功能、Rspo2调控Wnt/β-catenin信号通路的相关机制及其对骨骼系统的影响作一综述,以期为骨相关疾病的防治提供新的思路和途径。
文摘目的探讨R-spondin3(RSPO3)在乳腺癌中的表达及预后价值。方法应用TIMER、癌症基因组图谱(The Cancer Genome Atlas,TCGA)、基因表达谱数据动态分析(gene expression profilling in-teractive analysis 2,GEPIA2)、人类蛋白质表达图谱(Human Protein Atlas,HPA)等数据库分析RSPO3在乳腺癌组织和癌周正常组织中的差异表达,并分析其表达水平与乳腺癌病理学参数之间的相关性;GEPIA2数据库探讨RSPO3转录本在乳腺癌中的表达及其结构特征;Kaplan-Meier Plotter绘制RSPO3与乳腺癌患者的预后生存曲线;运用基因本体论(gene ontology,GO)和京都基因与基因组百科全书(Kyoto encyclopedia of genes and genomes,KEGG)等对其进行基因功能富集分析和代谢通路分析;应用TIMER数据库分析RSPO3的表达水平与肿瘤微环境中免疫细胞浸润的相关性。结果RSPO3在乳腺癌中呈低表达,且其表达水平与乳腺癌患者的年龄、肿瘤最大径、分子分型相关,在乳腺癌中低表达的RSPO3与患者的预后不良相关;GO功能富集分析显示,RSPO3相互作用的基因主要富集于免疫细胞及其受体等参与的生物学过程;免疫细胞浸润分析结果显示,RSPO3在乳腺癌组织中的表达水平与CD8^(+)T细胞、CD4^(+)T细胞、CD4^(+)记忆T细胞、巨噬细胞、B细胞等的浸润水平呈正相关,而与调节性T细胞(Treg细胞)的浸润水平呈负相关;KEGG代谢通路分析显示,RSPO3可能参与Wnt/β-catenin通路。结论在乳腺癌中低表达的RSPO3与患者的不良预后相关,其可能通过抑制免疫细胞浸润及活化Wnt/β-catenin通路参与乳腺癌的进展。
基金supported by the National Institutes of Health (NIH) National Institute of Arthritis and Musculoskeletal Diseases (NIAMS)funding of the University of Pennsylvania Center for Musculoskeletal Disorders (PCMD) (P30AR069619)the University of Michigan Integrative Musculoskeletal Health Core Center (P30AR069620)+1 种基金supported by NIH NIAMS R01AR066028supported by NIH NIAMS F31AR065858
文摘The R-spondin family of proteins are Wnt agonists, and the complete embryonic disruption of Rspo2 results in skeletal developmental defects that recapitulate the phenotype observed with Lrp5/6 deficiency. Previous work has shown that R-spondin-2(Rspo2, RSPO2) is both highly expressed in Wnt-stimulated pre-osteoblasts and its overexpression induces osteoblast differentiation in the same cells, supporting its putative role as a positive autocrine regulator of osteoblastogenesis. However, the role of Rspo2 in regulating osteoblastogenesis and bone formation in postnatal bone has not been explored. Here we show that limb-bud progenitor cells from Rspo2 knockout mice undergo reduced mineralization during osteoblastogenesis in vitro and have a corresponding alteration in their osteogenic gene expression profile. We also generated the first Rspo2 conditional knockout(Rspo2 floxed) mouse and disrupted Rspo2 expression in osteoblast-lineage cells by crossing to the Osteocalcin-Cre mouse line(OcnCre + Rspo2 ^(f/f)). Ocn-Cre + Rspo2 f/fmale and female mice at 1, 3, and 6 months were examined. Ocn-Cre + Rspo2 f/fmice are decreased in overall body size compared to their control littermates and have decreased bone mass. Histomorphometric analysis of1-month-old mice revealed a similar number of osteoblasts and mineralizing surface per bone surface with a simultaneous decrease in mineral apposition and bone formation rates. Consistent with this observation, serum osteocalcin in 3-month-old Ocn-Cre +Rspo2 f/fwas reduced, and bone marrow-mesenchymal stem cells from Ocn-Cre + Rspo2 f/fmice undergo less mineralization in vitro.Finally, gene expression analysis and immunohistochemistry of mature bone shows reduced beta-catenin signaling in Ocn-Cre +Rspo2 f/f. Overall, RSPO2 reduces osteoblastogenesis and mineralization, leading to reduced bone mass.
文摘R-spondins是包含凝血酶敏感蛋白1型重复序列[thrombospondin type 1 repeat(TSR-1)-containing proteins]的结构域家族,由四种分泌糖蛋白R-spondin 1-4组成。R-spondins通过富含亮氨酸的G蛋白偶联受体4/5/6(leucine-rish repeat-containing G-protein coupled receptor 4/5/6,LGR4/5/6)、细胞表面跨膜E3泛素连接酶ZNRF3[(zinc and ring finger 3)/RNF43(ring finger protein 43)]、硫酸乙酰肝素蛋白多糖(heparan sulfate proteoglycans,HSPGs)、包含GTPase激活蛋白1(IQ motif containing GTPase-activating protein 1,IQGAP1)来增强WNT/β-catenin信号通路,进而在人类胚胎发育、组织和器官稳定、干细胞自我更新等方面发挥作用。近年来研究发现R-spondins参与胚胎骨发育、成体骨形成和骨关节疾病的发生发展,对R-spondins的研究可能成为骨代谢疾病新的治疗方向。本文将对R-spondins增强WNT/β-catenin信号通路的相关机制及其对胚胎骨发育、成体骨形成、骨质疏松和骨关节炎相关疾病的影响做一综述。
文摘背景与目的:结直肠癌的发生、发展涉及多个癌基因的激活和抑癌基因的失活,野生型R-脊椎蛋白3(R-spondin 3,RSPO3)在结直肠癌生长中的作用目前尚不清楚,本研究旨在探讨RSPO3对结直肠癌生长的影响并探索其潜在机制。方法:采用生物信息学分析RSPO3在结直肠癌及泛癌组织中的表达,分析结直肠癌中RSPO3表达与自然杀伤(natural killer,NK)细胞浸润、NK细胞激活分子表达的相关性。利用短发夹RNA(short hairpin RNA,shRNA)和慢病毒感染建立RSPO3敲减的SW480-RSPO3-KD细胞株、RSPO3过表达的HCT116-RSPO3-OE细胞株及相应的对照细胞株。采用细胞计数试剂盒-8(cell counting kit-8,CCK-8)检测体外各稳定转染细胞株的细胞增殖。采用流式细胞术分析各稳定转染细胞株的细胞周期、裸小鼠脾脏和移植瘤组织中NK细胞的比例。通过裸小鼠皮下移植瘤模型观察RSPO3敲减或过表达的结肠癌细胞在裸小鼠体内的生长。利用双荧光素酶报告基因系统检测RSPO3敲减或过表达对结肠癌Wnt基因转录活性的影响。结果:生物信息学分析显示,RSPO3在多种实体瘤肿瘤组织包括结直肠癌组织中的表达显著低于相应的癌旁组织。RSPO3敲减或过表达不影响体外SW480和HCT116结肠癌细胞的增殖(P>0.05)和细胞周期(P>0.05)。但在裸小鼠体内,与对照细胞相比,RSPO3敲减显著促进SW480细胞移植瘤的生长(260.2±162.4 vs 1311.7±570.1,P<0.05),而RSPO3过表达则显著抑制HCT116细胞移植瘤的生长(1549.0±241.2 vs 512.1±250.0,P<0.05)。流式细胞术分析发现,在荷移植瘤裸小鼠体内,RSPO3敲减显著减少了脾脏和移植瘤组织中NK细胞的比例(脾脏:6.42±0.94 vs 5.25±0.59,P=0.04;移植瘤:8.27±0.29 vs 6.48±1.48,P=0.04);而RSPO3过表达显著增加了脾脏和移植瘤组织中NK细胞的比例(脾脏:5.29±0.16 vs 7.02±0.49,P=0.01;移植瘤:6.39±0.39 vs 8.14±0.34,P<0.05)。癌症基因组图谱(The Cancer Genome Atlas,TCGA)数据相关性分析显示,RSPO3表达与NK细胞表面标志物CD56(r=0.58,P<0.05)和CD16(r=0.64,P<0.05)的表达显著正相关,并与NK细胞激活标志物CD69(r=0.51,P<0.05)和KLRB1(r=0.37,P<0.05)的表达显著正相关。双荧光素酶报告基因实验结果显示,RSPO3敲减后Wnt荧光素酶活性下调(1.0±0.0 vs 0.45±0.09,P<0.05),而RSPO3过表达后Wnt荧光素酶活性上调(1.0±0.0 vs 1.75±0.14,P<0.05)。结论:RSPO3能在体内显著抑制结直肠癌移植瘤的生长,并能增加移植瘤组织中NK细胞浸润,RSPO3是一个潜在的结直肠癌的抑制基因。
文摘R-spondins are secretory proteins localized in the endoplasmic reticulum and Golgi bodies and are processed through the secretory pathway.Among the R-spondin family,RSPO2 has emanated as a novel regulator of Wnt signaling,which has now been acknowledged in numerous in vitro and in vivo studies.Cancer is an abnormal growth of cells that proliferates and spreads uncontrollably due to the accumulation of genetic and epigenetic factors that constitutively activate Wnt signaling in various types of cancer.Colorectal cancer (CRC) begins when cells in the colon and rectum follow an indefinite pattern of division due to aberrant Wnt activation as one of the key hallmarks.Decades-long progress in research on R-spondins has demonstrated their oncogenic function in distinct cancer types,particularly CRC.As a critical regulator of the Wnt pathway,it modulates several phenotypes of cells,such as cell proliferation,invasion,migration,and cancer stem cell properties.Recently,RSPO mutations,gene rearrangements,fusions,copy number alterations,and altered gene expression have also been identified in a variety of cancers,including CRC.In this review,we addressed the recent updates regarding the recurrently altered R-spondins with special emphasis on the RSPO2 gene and its involvement in potentiating Wnt signaling in CRC.In addition to the compelling physiological and biological roles in cellular fate and regulation,we propose that RSPO2 would be valuable as a potential biomarker for prognostic,diagnostic,and therapeutic use in CRC.
基金supported in part by the National Key Research and Development Program of China(2021YFA1301400)the National Natural Science Foundation of China(31930035,91942311,32061143028,32170895,82100575)+2 种基金China Postdoctoral Science Foundation(2021M692127,2022T150423)Shanghai Science and Technology Commission(20410714000,20JC1410100,22JC1402600,22ZR1480700,22QA1408000)Shanghai Frontiers Science Center of Cellular Homeostasis and Human Diseases.
文摘Alveolar macrophages(AMs)are self-maintained immune cells that play vital roles in lung homeostasis and immunity.Although reporter mice and culture systems have been established for studying macrophages,an accurate and specific reporter line for alveolar macrophage study is still not available.Here we reported a novel Rspo1-tdTomato gene reporter mouse line that could specifically label mouse AMs in a cell-intrinsic manner.Using this reporter system,we visualized the dynamics of alveolar macrophages intravitally under steady state and characterized the alveolar macrophage differentiation under in vitro condition.By performing ATAC-seq,we found that insertion of the tdTomato cassette in the Rspo1 locus increased the accessibility of a PPARE motif within the Rspo1 locus and revealed a potential regulation by key transcription factor PPAR-γfor alveolar macrophage differentiation in vitro and in vivo.Consistently,perturbation of PPAR-γby its agonist rosiglitazone or inhibitor GW9662 resulted in corresponding alteration of tdTomato expression in alveolar macrophages together with the transcription of PPAR-γdownstream target genes.Furthermore,global transcriptomic analyses of AMs from the wild type mice and the Rspo1-tdTomato mice showed comparable gene expression profiles,especially those AM-specific genes,confirming that the insertion of the tdTomato cassette in the Rspo1 locus does not impact the cell identity and biological function of AMs under normal condition.Taken together,our study provides an alternative tool for in vivo and in vitro labeling of alveolar macrophages with high specificity which could also be utilized as an indicator of PPAR-γactivity for future development of PPAR-γspecific targeting drugs.
