Objective:Lymphatic endothelial cell(LEC)proliferation is essential for lymphangiogenesis.Hypoxia induces lymphangiogenesis,but it directly inhibits LEC proliferation and the underlying mechanisms have not been fully ...Objective:Lymphatic endothelial cell(LEC)proliferation is essential for lymphangiogenesis.Hypoxia induces lymphangiogenesis,but it directly inhibits LEC proliferation and the underlying mechanisms have not been fully understood.The aim of this study was to investigate the role of carcinoembryonic antigen-related cell adhesion molecule 1(CEACAM1)in hypoxia-repressed LEC proliferation.Methods:Human dermal lymphatic endothelial cells(HDLECs)were cultured under normoxic or hypoxic conditions,and cell proliferation was determined using MTT or CCK-8 assays.CEACAM1 expression was silenced by siRNA transfection.Activation of mitogen-activated protein kinases(MAPKs)was examined by Western blotting and blocked by specific inhibitors.Results:Under hypoxia,HDLECs proliferation was suppressed and CEACAM1 expression was downregulated.Silence of CEACAM1 in normoxia inhibited HDLECs proliferation and did not further decrease proliferation in HDLECs in response to hypoxia,suggesting that CEACAM1 may mediate hypoxia-induced inhibition of HDLECs proliferation.In addition,silence of CEACAM1 increased phosphorylation of MAPK molecules:extracellular signal-regulated kinase(ERK),p38 MAPK and Jun N-terminal kinase(JNK)in HDLECs.However,only inhibition of the JNK pathway rescued the reduction of HDLEC proliferation induced by CEACAM1 silence.Conclusion:Our results suggested that hypoxia downregulates CEACAM1 expression by activation of the JNK pathway,leading to inhibition of HDLEC proliferation.These findings may help to understand the mechanisms of LEC-specific response to hypoxia and develop novel therapies for pathological lymphangiogenesis.展开更多
The tumor microenvironment is a complex network of cells,extracellular matrix,and signaling molecules that plays a critical role in tumor progression and metastasis.Lymphatic and blood vessels are major routes for sol...The tumor microenvironment is a complex network of cells,extracellular matrix,and signaling molecules that plays a critical role in tumor progression and metastasis.Lymphatic and blood vessels are major routes for solid tumor metastasis and essential parts of tumor drainage conduits.However,recent studies have shown that lymphatic endothelial cells(LECs)and blood endothelial cells(BECs)also play multifaceted roles in the tumor microenvironment beyond their structural functions,particularly in hepatocellular carcinoma(HCC).This comprehensive review summarizes the diverse roles played by LECs and BECs in HCC,including their involvement in angiogenesis,immune modulation,lymphangiogenesis,and metastasis.By providing a detailed account of the complex interplay between LECs,BECs,and tumor cells,this review aims to shed light on future research directions regarding the immune regulatory function of LECs and potential therapeutic targets for HCC.展开更多
Gorham-Stout disease(GSD)is a sporadic chronic disease characterized by progressive bone dissolution,absorption,and disappearance along with lymphatic vessel infiltration in bone-marrow cavities.Although the osteolyti...Gorham-Stout disease(GSD)is a sporadic chronic disease characterized by progressive bone dissolution,absorption,and disappearance along with lymphatic vessel infiltration in bone-marrow cavities.Although the osteolytic mechanism of GSD has been widely studied,the cause of lymphatic hyperplasia in GSD is rarely investigated.In this study,by comparing the RNA expression profile of osteoclasts(OCs)with that of OC precursors(OCPs)by RNA sequencing,we identified a new factor,semaphorin 3A(Sema3A),which is an osteoprotective factor involved in the lymphatic expansion of GSD.Compared to OCPs,OCs enhanced the growth,migration,and tube formation of lymphatic endothelial cells(LECs),in which the expression of Sema3A is low compared to that in OCPs.In the presence of recombinant Sema3A,the growth,migration,and tube formation of LECs were inhibited,further confirming the inhibitory effect of Sema3A on LECs in vitro.Using an LEC-induced GSD mouse model,the effect of Sema3A was examined by injecting lentivirus-expressing Sema3A into the tibiae in vivo.We found that the overexpression of Sema3A in tibiae suppressed the expansion of LECs and alleviated bone loss,whereas the injection of lentivirus expressing Sema3A short hairpin RNA(shRNA)into the tibiae caused GSD-like phenotypes.Histological staining further demonstrated that OCs decreased and osteocalcin increased after Sema3A lentiviral treatment,compared with the control.Based on the above results,we propose that reduced Sema3A in OCs is one of the mechanisms contributing to the pathogeneses of GSD and that expressing Sema3A represents a new approach for the treatment of GSD.展开更多
Cholangiocarcinoma(CCA) is a highly aggressive epithelial malignancy still carrying a dismal prognosis, owing to early lymph node metastatic dissemination and striking resistance to conventional chemotherapy. Although...Cholangiocarcinoma(CCA) is a highly aggressive epithelial malignancy still carrying a dismal prognosis, owing to early lymph node metastatic dissemination and striking resistance to conventional chemotherapy. Although mechanisms underpinning CCA progression are still a conundrum, it is now increasingly recognized that the desmoplastic microenvironment developing in conjunction with biliary carcinogenesis, recently renamed tumor reactive stroma(TRS), behaves as a paramount tumor-promoting driver. Indeed, once being recruited, activated and dangerously co-opted by neoplastic cells, the cellular components of the TRS(myofibroblasts, macrophages, endothelial cells and mesenchymal stem cells) continuously rekindle malignancy by secreting a huge variety of soluble factors(cyto/chemokines, growth factors, morphogens and proteinases). Furthermore, these factors are long-term stored within an abnormally remodeled extracellular matrix(ECM), which in turn can deleteriously mold cancer cell behavior. In this review, we will highlight evidence for the active role played by reactive stromal cells(as well as by the TRS-associated ECM) in CCA progression, including an overview of the most relevant TRS-derived signals possibly fueling CCA cell aggressiveness. Hopefully, a deeper knowledge of the paracrine communications reciprocally exchanged between cancer and stromal cells will steer the development of innovative, combinatorial therapies, which can finally hinder the progression of CCA, as well as of other cancer types with abundant TRS, such as pancreatic and breast carcinomas.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.81873473 and No.91939110)Academic Promotion Program of Shandong First Medical University(No.2019QL014)Shandong Taishan Scholarship(Ju Liu).
文摘Objective:Lymphatic endothelial cell(LEC)proliferation is essential for lymphangiogenesis.Hypoxia induces lymphangiogenesis,but it directly inhibits LEC proliferation and the underlying mechanisms have not been fully understood.The aim of this study was to investigate the role of carcinoembryonic antigen-related cell adhesion molecule 1(CEACAM1)in hypoxia-repressed LEC proliferation.Methods:Human dermal lymphatic endothelial cells(HDLECs)were cultured under normoxic or hypoxic conditions,and cell proliferation was determined using MTT or CCK-8 assays.CEACAM1 expression was silenced by siRNA transfection.Activation of mitogen-activated protein kinases(MAPKs)was examined by Western blotting and blocked by specific inhibitors.Results:Under hypoxia,HDLECs proliferation was suppressed and CEACAM1 expression was downregulated.Silence of CEACAM1 in normoxia inhibited HDLECs proliferation and did not further decrease proliferation in HDLECs in response to hypoxia,suggesting that CEACAM1 may mediate hypoxia-induced inhibition of HDLECs proliferation.In addition,silence of CEACAM1 increased phosphorylation of MAPK molecules:extracellular signal-regulated kinase(ERK),p38 MAPK and Jun N-terminal kinase(JNK)in HDLECs.However,only inhibition of the JNK pathway rescued the reduction of HDLEC proliferation induced by CEACAM1 silence.Conclusion:Our results suggested that hypoxia downregulates CEACAM1 expression by activation of the JNK pathway,leading to inhibition of HDLEC proliferation.These findings may help to understand the mechanisms of LEC-specific response to hypoxia and develop novel therapies for pathological lymphangiogenesis.
基金Supported by National Natural Science Foundation of China,No.81702923,and No.81971503Open Project of State Key Laboratory of Medical Immunology,No.NKLMI2023K03+1 种基金Shanghai Shen Kang Hospital Development Center Clinical Science and Technology Innovation Project,No.SHDC12020104Basic Medical Research Project of Naval Medical University,No.2022QN072.
文摘The tumor microenvironment is a complex network of cells,extracellular matrix,and signaling molecules that plays a critical role in tumor progression and metastasis.Lymphatic and blood vessels are major routes for solid tumor metastasis and essential parts of tumor drainage conduits.However,recent studies have shown that lymphatic endothelial cells(LECs)and blood endothelial cells(BECs)also play multifaceted roles in the tumor microenvironment beyond their structural functions,particularly in hepatocellular carcinoma(HCC).This comprehensive review summarizes the diverse roles played by LECs and BECs in HCC,including their involvement in angiogenesis,immune modulation,lymphangiogenesis,and metastasis.By providing a detailed account of the complex interplay between LECs,BECs,and tumor cells,this review aims to shed light on future research directions regarding the immune regulatory function of LECs and potential therapeutic targets for HCC.
基金supported by the National Natural Science Foundation of China(No.81974321)the Discipline Innovation and Talent Introduction Program to Universities from Ministry of Education of China(Project 111)+3 种基金the Tackling Project for Science and Technology of Xinxiang City(No.GG2019003)the Natural Science Foundation of Henan Province of China(No.212300410173)the State Administration of Traditional Chinese Medicine Young Qi Huang Scholar,and the Innovation Team Project of Scientific Research of Traditional Chinese Medicine of Shanghai Health Committee(No.2022CX001)China.
文摘Gorham-Stout disease(GSD)is a sporadic chronic disease characterized by progressive bone dissolution,absorption,and disappearance along with lymphatic vessel infiltration in bone-marrow cavities.Although the osteolytic mechanism of GSD has been widely studied,the cause of lymphatic hyperplasia in GSD is rarely investigated.In this study,by comparing the RNA expression profile of osteoclasts(OCs)with that of OC precursors(OCPs)by RNA sequencing,we identified a new factor,semaphorin 3A(Sema3A),which is an osteoprotective factor involved in the lymphatic expansion of GSD.Compared to OCPs,OCs enhanced the growth,migration,and tube formation of lymphatic endothelial cells(LECs),in which the expression of Sema3A is low compared to that in OCPs.In the presence of recombinant Sema3A,the growth,migration,and tube formation of LECs were inhibited,further confirming the inhibitory effect of Sema3A on LECs in vitro.Using an LEC-induced GSD mouse model,the effect of Sema3A was examined by injecting lentivirus-expressing Sema3A into the tibiae in vivo.We found that the overexpression of Sema3A in tibiae suppressed the expansion of LECs and alleviated bone loss,whereas the injection of lentivirus expressing Sema3A short hairpin RNA(shRNA)into the tibiae caused GSD-like phenotypes.Histological staining further demonstrated that OCs decreased and osteocalcin increased after Sema3A lentiviral treatment,compared with the control.Based on the above results,we propose that reduced Sema3A in OCs is one of the mechanisms contributing to the pathogeneses of GSD and that expressing Sema3A represents a new approach for the treatment of GSD.
文摘Cholangiocarcinoma(CCA) is a highly aggressive epithelial malignancy still carrying a dismal prognosis, owing to early lymph node metastatic dissemination and striking resistance to conventional chemotherapy. Although mechanisms underpinning CCA progression are still a conundrum, it is now increasingly recognized that the desmoplastic microenvironment developing in conjunction with biliary carcinogenesis, recently renamed tumor reactive stroma(TRS), behaves as a paramount tumor-promoting driver. Indeed, once being recruited, activated and dangerously co-opted by neoplastic cells, the cellular components of the TRS(myofibroblasts, macrophages, endothelial cells and mesenchymal stem cells) continuously rekindle malignancy by secreting a huge variety of soluble factors(cyto/chemokines, growth factors, morphogens and proteinases). Furthermore, these factors are long-term stored within an abnormally remodeled extracellular matrix(ECM), which in turn can deleteriously mold cancer cell behavior. In this review, we will highlight evidence for the active role played by reactive stromal cells(as well as by the TRS-associated ECM) in CCA progression, including an overview of the most relevant TRS-derived signals possibly fueling CCA cell aggressiveness. Hopefully, a deeper knowledge of the paracrine communications reciprocally exchanged between cancer and stromal cells will steer the development of innovative, combinatorial therapies, which can finally hinder the progression of CCA, as well as of other cancer types with abundant TRS, such as pancreatic and breast carcinomas.
