Hypertrophic scar and keloid are a major medical problem,which may lead to disfigurement,growth restriction,and permanent loss of function,causing severe physical,psychological,and economic burdens.1 When skin injury ...Hypertrophic scar and keloid are a major medical problem,which may lead to disfigurement,growth restriction,and permanent loss of function,causing severe physical,psychological,and economic burdens.1 When skin injury occurs,the wound heals through a dynamic series of physiological events,including blood clotting,granulation tissue formation,re-epithelialization,and extracellular matrix remodeling.2 However,the newly formed extracellular matrix in a scar may never achieve the flexibility or strength of the original tissue.展开更多
Skin serves as the first-order protective barrier against the environment and any significant disruptions in skin integrity must be promptly restored.Despite significant advances in therapeutic strategies,effective ma...Skin serves as the first-order protective barrier against the environment and any significant disruptions in skin integrity must be promptly restored.Despite significant advances in therapeutic strategies,effective management of large chronic skin wounds remains a clinical challenge.Dermal fibroblasts are the primary cell type responsible for remodeling the extracellular matrix(ECM)in wound healing.Here,we investigated whether ECM derived from exogenous fibroblasts,in combination with keratinocytes,promoted scarless cutaneous wound healing.To overcome the limited lifespan of primary dermal fibroblasts,we established reversibly immortalized mouse dermal fibroblasts(imDFs),which were non-tumorigenic,expressed dermal fibroblast markers,and were responsive to TGF-β1 stimulation.The decellularized ECM prepared from both imDFs and primary dermal fi-broblasts shared similar expression profiles of extracellular matrix proteins and promoted the proliferation of keratinocyte(iKera)cells.The imDFs-derived ECM solicited no local immune response.While the ECM and to a lesser extent imDFs enhanced skin wound healing with excessive fibrosis,a combination of imDFs-derived ECM and iKera cells effectively promoted the re-epithelization and scarless healing of full-thickness skin wounds.These findings strongly suggest that dermal fibroblast-derived ECM,not fibroblasts themselves,may synergize with keratinocytes in regulating scarless healing and re-epithelialization of skin wounds.Given its low immu-nogenic nature,imDFs-derived ECM should be a valuable resource of skin-specific biomaterial for wound healing and skin tissue engineering.展开更多
Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs a...Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs are now known to play crucial roles in all organ systems.BMPs are important in embryogenesis and development,and also in maintenance of adult tissue homeostasis.Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects,highlighting the essential functions of BMPs.In this review,we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development.A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling.展开更多
Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polar...Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.展开更多
Effective bone regeneration through tissue engineering requires a combination of osteogenic progenitors,osteoinductive biofactors and biocompatible scaffold materials.Mesenchymal stem cells(MSCs)represent the most pro...Effective bone regeneration through tissue engineering requires a combination of osteogenic progenitors,osteoinductive biofactors and biocompatible scaffold materials.Mesenchymal stem cells(MSCs)represent the most promising seed cells for bone tissue engineering.As multipotent stem cells that can self-renew and differentiate into multiple lineages including bone and fat,MSCs can be isolated from numerous tissues and exhibit varied differentiation potential.To identify an optimal progenitor cell source for bone tissue engineering,we analyzed the proliferative activity and osteogenic potential of four commonly-used mouse MSC sources,including immortalized mouse embryonic fibroblasts(iMEF),immortalized mouse bone marrow stromal stem cells(imBMSC),immortalized mouse calvarial mesenchymal progenitors(iCAL),and immortalized mouse adipose-derived mesenchymal stem cells(iMAD).We found that iMAD exhibited highest osteogenic and adipogenic capabilities upon BMP9 stimulation in vitro,whereas iMAD and iCAL exhibited highest osteogenic capability in BMP9-induced ectopic osteogenesis and critical-sized calvarial defect repair.Transcriptomic analysis revealed that,while each MSC line regulated a distinct set of target genes upon BMP9 stimulation,all MSC lines underwent osteogenic differentiation by regulating osteogenesis-related signaling including Wnt,TGF-β,PI3K/AKT,MAPK,Hippo and JAK-STAT pathways.Collectively,our results demonstrate that adipose-derived MSCs represent optimal progenitor sources for cell-based bone tissue engineering.展开更多
The transcription factor Sox9 was first discovered in patients with campomelic dysplasia,a haploinsufficiency disorder with skeletal deformities caused by dysregulation of Sox9 expression during chondrogenesis.Since t...The transcription factor Sox9 was first discovered in patients with campomelic dysplasia,a haploinsufficiency disorder with skeletal deformities caused by dysregulation of Sox9 expression during chondrogenesis.Since then,its role as a cell fate determiner during embryonic development has been well characterized;Sox9 expression differentiates cells derived from all three germ layers into a large variety of specialized tissues and organs.However,recent data has shown that ectoderm-and endoderm-derived tissues continue to express Sox9 in mature organs and stem cell pools,suggesting its role in cell maintenance and specification during adult life.The versatility of Sox9 may be explained by a combination of posttranscriptional modifications,binding partners,and the tissue type in which it is expressed.Considering its importance during both development and adult life,it follows that dysregulation of Sox9 has been implicated in various congenital and acquired diseases,including fibrosis and cancer.This review provides a summary of the various roles of Sox9 in cell fate specification,stem cell biology,and related human diseases.Ultimately,understanding the mechanisms that regulate Sox9 will be crucial for developing effective therapies to treat disease caused by stem cell dysregulation or even reverse organ damage.展开更多
Cartilage injuries caused by arthritis or trauma pose formidable challenges for effective clinical management due to the limited intrinsic proliferative capability of chondrocytes.Autologous stem cell-based therapies ...Cartilage injuries caused by arthritis or trauma pose formidable challenges for effective clinical management due to the limited intrinsic proliferative capability of chondrocytes.Autologous stem cell-based therapies and transgene-enhanced cartilage tissue engineering may open new avenues for the treatment of cartilage injuries.Bone morphogenetic protein 2(BMP2)induces effective chondrogenesis of mesenchymal stem cells(MSCs)and can thus be explored as a potential therapeutic agent for cartilage defect repair.However,BMP2 also induces robust endochondral ossification.Although the precise mechanisms through which BMP2 governs the divergence of chondrogenesis and osteogenesis remain to be fully understood,blocking endochondral ossification during BMP2-induced cartilage formation may have practical significance for cartilage tissue engineering.Here,we investigate the role of Sox9-donwregulated Smad7 in BMP2-induced chondrogenic differentiation of MSCs.We find that overexpression of Sox9 leads to a decrease in BMP2-induced Smad7 expression in MSCs.Sox9 inhibits BMP2-induced expression of osteopontin while enhancing the expression of chondrogenic marker Col2a1 in MSCs.Forced expression of Sox9 in MSCs promotes BMP2-induced chondrogenesis and suppresses BMP2-induced endochondral ossification.Constitutive Smad7 expression inhibits BMP2-induced chondrogenesis in stem cell implantation assay.Mouse limb explant assay reveals that Sox9 expands BMP2-stimulated chondrocyte proliferating zone while Smad7 promotes BMP2-intitated hypertrophic zone of the growth plate.Cell cycle analysis indicates that Smad7 induces significant early apoptosis in BMP2-stimulated MSCs.Taken together,our results strongly suggest that Sox9 may facilitate BMP2-induced chondrogenesis by downregulating Smad7,which can be exploited for effective cartilage tissue engineering.展开更多
Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartila...Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue.Here,we review the current understanding of the most important biological regulators of chondrogenesis and their interactions,to provide insight into potential applications for cartilage tissue engineering.These include various signaling pathways,including fibroblast growth factors(FGFs),transforming growth factor b(TGF-b)/bone morphogenic proteins(BMPs),Wnt/b-catenin,Hedgehog,Notch,hypoxia,and angiogenic signaling pathways.Transcriptional and epigenetic regulation of chondrogenesis will also be discussed.Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.展开更多
Wnt signaling plays a major role in regulating cell proliferation and differentiation.The Wnt ligands are a family of 19 secreted glycoproteins that mediate their signaling effects via binding to Frizzled receptors an...Wnt signaling plays a major role in regulating cell proliferation and differentiation.The Wnt ligands are a family of 19 secreted glycoproteins that mediate their signaling effects via binding to Frizzled receptors and LRP5/6 coreceptors and transducing the signal either throughβ-catenin in the canonical pathway or through a series of other proteins in the nonca-nonical pathway.Many of the individual components of both canonical and noncanonical Wnt signaling have additional functions throughout the body,establishing the complex interplay between Wnt signaling and other signaling pathways.This crosstalk between Wnt signaling and other pathways gives Wnt signaling a vital role in many cellular and organ processes.Dys-regulation of this system has been implicated in many diseases affecting a wide array of organ systems,including cancer and embryological defects,and can even cause embryonic lethality.The complexity of this system and its interacting proteins have made Wnt signaling a target for many therapeutic treatments.However,both stimulatory and inhibitory treatments come with potential risks that need to be addressed.This review synthesized much of the current knowl-edge on the Wnt signaling pathway,beginning with the history of Wnt signaling.It thoroughly described the different variants of Wnt signaling,including canonical,noncanonical Wnt/PCP,and the noncanonical Wnt/Ca2+pathway.Further description involved each of its components and their involvement in other cellular processes.Finally,this review explained the various other pathways and processes that crosstalk with Wnt signaling.展开更多
基金supported in part by research grants from the Natural Science Foundation of China(No.82102696 to J.F.)the Chongqing Natural Science Foundation of China(No.2024NSCQ-MSX0073 to J.F.)+1 种基金the US National Institutes of Health(No.CA226303 to T.C.H.DE030480 to R.R.R.).
文摘Hypertrophic scar and keloid are a major medical problem,which may lead to disfigurement,growth restriction,and permanent loss of function,causing severe physical,psychological,and economic burdens.1 When skin injury occurs,the wound heals through a dynamic series of physiological events,including blood clotting,granulation tissue formation,re-epithelialization,and extracellular matrix remodeling.2 However,the newly formed extracellular matrix in a scar may never achieve the flexibility or strength of the original tissue.
基金supported in part by research grants from the Natural Science Foundation of China(82102696,JF)Chongqing Nat-ural Science Foundation(2024NSCQ-MSX0073,JF)+3 种基金the National Institutes of Health(CA226303 to TCH,and DE030480 to RRR)supported in part by The University of Chicago Comprehensive Cancer Center Support Grant(P30CA014599)the National Center for Advancing Translational Sciences of the National Institutes of Health through Grant Number UL1 TR000430supported by the Mabel Green Myers Research Endowment Fund and The University of Chicago Orthopaedics Alumni Fund.
文摘Skin serves as the first-order protective barrier against the environment and any significant disruptions in skin integrity must be promptly restored.Despite significant advances in therapeutic strategies,effective management of large chronic skin wounds remains a clinical challenge.Dermal fibroblasts are the primary cell type responsible for remodeling the extracellular matrix(ECM)in wound healing.Here,we investigated whether ECM derived from exogenous fibroblasts,in combination with keratinocytes,promoted scarless cutaneous wound healing.To overcome the limited lifespan of primary dermal fibroblasts,we established reversibly immortalized mouse dermal fibroblasts(imDFs),which were non-tumorigenic,expressed dermal fibroblast markers,and were responsive to TGF-β1 stimulation.The decellularized ECM prepared from both imDFs and primary dermal fi-broblasts shared similar expression profiles of extracellular matrix proteins and promoted the proliferation of keratinocyte(iKera)cells.The imDFs-derived ECM solicited no local immune response.While the ECM and to a lesser extent imDFs enhanced skin wound healing with excessive fibrosis,a combination of imDFs-derived ECM and iKera cells effectively promoted the re-epithelization and scarless healing of full-thickness skin wounds.These findings strongly suggest that dermal fibroblast-derived ECM,not fibroblasts themselves,may synergize with keratinocytes in regulating scarless healing and re-epithelialization of skin wounds.Given its low immu-nogenic nature,imDFs-derived ECM should be a valuable resource of skin-specific biomaterial for wound healing and skin tissue engineering.
基金The reported work was in part supported by research grants from the National Institutes of Health(AR50142 and AR054381 to RCH and HHL)RW,JG,and OI were recipients of the Pritzker Summer Research Fellowship funded through a NIH T-35 training grant(NIDDK).AH was a recipient of the Urban Leadership Fellowship from Miami University.
文摘Bone Morphogenetic Proteins(BMPs)are a group of signaling molecules that belongs to the Transforming Growth Factor-b(TGF-b)superfamily of proteins.Initially discovered for their ability to induce bone formation,BMPs are now known to play crucial roles in all organ systems.BMPs are important in embryogenesis and development,and also in maintenance of adult tissue homeostasis.Mouse knockout models of various components of the BMP signaling pathway result in embryonic lethality or marked defects,highlighting the essential functions of BMPs.In this review,we first outline the basic aspects of BMP signaling and then focus on genetically manipulated mouse knockout models that have helped elucidate the role of BMPs in development.A significant portion of this review is devoted to the prominent human pathologies associated with dysregulated BMP signaling.
基金The authors’research efforts were supported in part by research grants from the NIH(AT004418 to TCH)the 973 Program of Ministry of Science and Technology(MOST)of China(#2011CB707900 to TCH)+1 种基金the Scoliosis Research Society(to MJL),MKM was a recipient of Howard Hughes Medical Institute Medical Research FellowshipCS was a recipient of the Pritzker Summer Research Fellowship funded through a NIH T-35 training grant(NIDDK).
文摘Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.
基金by research grants from the Natural Science Foundation of China(82102696 to JF)the Chongqing Bayu Young Scholar Award(JF),the 2019 Chongqing Support Program for Entrepreneurship and Innovation(No.cx2019113 to JF)+4 种基金the 2019 Funding for Postdoctoral Research(Chongqing Human Resources and Social Security Bureau No.298 to JF)the National Institutes of Health(CA226303 to TCH,and DE030480 to RRR)supported by the Medical Scientist Training Program of the National Institutes of Health(T32 GM007281)supported in part by The University of Chicago Cancer Center Support Grant(P30CA014599)the National Center for Advancing Translational Sciences of the National Institutes of Health through Grant Number UL1TR002389-07.
文摘Effective bone regeneration through tissue engineering requires a combination of osteogenic progenitors,osteoinductive biofactors and biocompatible scaffold materials.Mesenchymal stem cells(MSCs)represent the most promising seed cells for bone tissue engineering.As multipotent stem cells that can self-renew and differentiate into multiple lineages including bone and fat,MSCs can be isolated from numerous tissues and exhibit varied differentiation potential.To identify an optimal progenitor cell source for bone tissue engineering,we analyzed the proliferative activity and osteogenic potential of four commonly-used mouse MSC sources,including immortalized mouse embryonic fibroblasts(iMEF),immortalized mouse bone marrow stromal stem cells(imBMSC),immortalized mouse calvarial mesenchymal progenitors(iCAL),and immortalized mouse adipose-derived mesenchymal stem cells(iMAD).We found that iMAD exhibited highest osteogenic and adipogenic capabilities upon BMP9 stimulation in vitro,whereas iMAD and iCAL exhibited highest osteogenic capability in BMP9-induced ectopic osteogenesis and critical-sized calvarial defect repair.Transcriptomic analysis revealed that,while each MSC line regulated a distinct set of target genes upon BMP9 stimulation,all MSC lines underwent osteogenic differentiation by regulating osteogenesis-related signaling including Wnt,TGF-β,PI3K/AKT,MAPK,Hippo and JAK-STAT pathways.Collectively,our results demonstrate that adipose-derived MSCs represent optimal progenitor sources for cell-based bone tissue engineering.
基金supported in part by the research grant from the National Institutes of Health(AR50142 to RCH)supported in part by The University of Chicago Core Facility Subsidy grant from the National Center for Advancing Translational Sciences(NCATS)of the National Institutes of Health through Grant UL1 TR000430.SD was a recipient of The University of Chicago Pritzker Fellowship and AOA Carolyn L.Kuckein Fellowship.
文摘The transcription factor Sox9 was first discovered in patients with campomelic dysplasia,a haploinsufficiency disorder with skeletal deformities caused by dysregulation of Sox9 expression during chondrogenesis.Since then,its role as a cell fate determiner during embryonic development has been well characterized;Sox9 expression differentiates cells derived from all three germ layers into a large variety of specialized tissues and organs.However,recent data has shown that ectoderm-and endoderm-derived tissues continue to express Sox9 in mature organs and stem cell pools,suggesting its role in cell maintenance and specification during adult life.The versatility of Sox9 may be explained by a combination of posttranscriptional modifications,binding partners,and the tissue type in which it is expressed.Considering its importance during both development and adult life,it follows that dysregulation of Sox9 has been implicated in various congenital and acquired diseases,including fibrosis and cancer.This review provides a summary of the various roles of Sox9 in cell fate specification,stem cell biology,and related human diseases.Ultimately,understanding the mechanisms that regulate Sox9 will be crucial for developing effective therapies to treat disease caused by stem cell dysregulation or even reverse organ damage.
基金The reported work was supported in part by research grants from the Natural Sciences Foundation of China(#81572142 and#81371972 to WH)the National Institutes of Health(AT004418 to TCH)+4 种基金the U.S.Department of Defense(OR130096 to JMW)the Scoliosis Research Society(TCH and MJL)the 973 Program of the Ministry of Science and Technology of China(#2011CB707906 to TCH)The reported work was also supported in part by The University of Chicago Cancer Center Support Grant(P30CA014599)the National Center for Advancing Translational Sciences of the National Institutes of Health through Grant Number UL1 TR000430.
文摘Cartilage injuries caused by arthritis or trauma pose formidable challenges for effective clinical management due to the limited intrinsic proliferative capability of chondrocytes.Autologous stem cell-based therapies and transgene-enhanced cartilage tissue engineering may open new avenues for the treatment of cartilage injuries.Bone morphogenetic protein 2(BMP2)induces effective chondrogenesis of mesenchymal stem cells(MSCs)and can thus be explored as a potential therapeutic agent for cartilage defect repair.However,BMP2 also induces robust endochondral ossification.Although the precise mechanisms through which BMP2 governs the divergence of chondrogenesis and osteogenesis remain to be fully understood,blocking endochondral ossification during BMP2-induced cartilage formation may have practical significance for cartilage tissue engineering.Here,we investigate the role of Sox9-donwregulated Smad7 in BMP2-induced chondrogenic differentiation of MSCs.We find that overexpression of Sox9 leads to a decrease in BMP2-induced Smad7 expression in MSCs.Sox9 inhibits BMP2-induced expression of osteopontin while enhancing the expression of chondrogenic marker Col2a1 in MSCs.Forced expression of Sox9 in MSCs promotes BMP2-induced chondrogenesis and suppresses BMP2-induced endochondral ossification.Constitutive Smad7 expression inhibits BMP2-induced chondrogenesis in stem cell implantation assay.Mouse limb explant assay reveals that Sox9 expands BMP2-stimulated chondrocyte proliferating zone while Smad7 promotes BMP2-intitated hypertrophic zone of the growth plate.Cell cycle analysis indicates that Smad7 induces significant early apoptosis in BMP2-stimulated MSCs.Taken together,our results strongly suggest that Sox9 may facilitate BMP2-induced chondrogenesis by downregulating Smad7,which can be exploited for effective cartilage tissue engineering.
基金The authors’ laboratories were supported in part byresearch grants from the National Institutes of Health(AR50142, AR054381, and AT004418 to RCH, HHL, and TCH)and Scoliosis Research Society (MJL)JDG and VT were recipientsof the Pritzker Summer Research Fellowship fundedthrough a NIH T-35 training grant (NIDDK)MKM was arecipient of Howard Hughes Medical Institute MedicalResearch Fellowship.
文摘Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue.Here,we review the current understanding of the most important biological regulators of chondrogenesis and their interactions,to provide insight into potential applications for cartilage tissue engineering.These include various signaling pathways,including fibroblast growth factors(FGFs),transforming growth factor b(TGF-b)/bone morphogenic proteins(BMPs),Wnt/b-catenin,Hedgehog,Notch,hypoxia,and angiogenic signaling pathways.Transcriptional and epigenetic regulation of chondrogenesis will also be discussed.Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.
基金supported in part by research grants from the National Institutes of Health(No.CA226303 to TCH and No.DE030480 to RRR)the American Shoulder and Elbow Surgeons PJI Research Grant(LLS).JF was supported in part by research grants from the Natural Science Foundation of China(No.82102696)+4 种基金the 2019 Science and Technology Research Plan Project of Chongqing Education Commission(China)(No.KJQN201900410)the 2019 Funding for Postdoctoral Research(Chongqing Human Resources and Social Security Bureau No.298)WW was supported by the Medical Scientist Training Program of the National Institutes of Health(No.T32 GM007281)This project was also supported in partby The University of Chicago Cancer Center Support Grant(No.P30CA014599)the National Center for Advancing Translational Sciences(NCATS)of the National Institutes of Health through Grant Number 5UL1TR002389.
文摘Wnt signaling plays a major role in regulating cell proliferation and differentiation.The Wnt ligands are a family of 19 secreted glycoproteins that mediate their signaling effects via binding to Frizzled receptors and LRP5/6 coreceptors and transducing the signal either throughβ-catenin in the canonical pathway or through a series of other proteins in the nonca-nonical pathway.Many of the individual components of both canonical and noncanonical Wnt signaling have additional functions throughout the body,establishing the complex interplay between Wnt signaling and other signaling pathways.This crosstalk between Wnt signaling and other pathways gives Wnt signaling a vital role in many cellular and organ processes.Dys-regulation of this system has been implicated in many diseases affecting a wide array of organ systems,including cancer and embryological defects,and can even cause embryonic lethality.The complexity of this system and its interacting proteins have made Wnt signaling a target for many therapeutic treatments.However,both stimulatory and inhibitory treatments come with potential risks that need to be addressed.This review synthesized much of the current knowl-edge on the Wnt signaling pathway,beginning with the history of Wnt signaling.It thoroughly described the different variants of Wnt signaling,including canonical,noncanonical Wnt/PCP,and the noncanonical Wnt/Ca2+pathway.Further description involved each of its components and their involvement in other cellular processes.Finally,this review explained the various other pathways and processes that crosstalk with Wnt signaling.
