C-mannosylation is a post-translational modification that occurs intracellularly in the endoplasmic reticulum.In humans,biosynthesis of C-mannosylation in proteins containing thrombospondin type 1 repeat is catalyzed ...C-mannosylation is a post-translational modification that occurs intracellularly in the endoplasmic reticulum.In humans,biosynthesis of C-mannosylation in proteins containing thrombospondin type 1 repeat is catalyzed by the DPY19 family;nonetheless,biological functions of protein C-mannosylation are not yet fully understood,especially in tumor progression.Vasculogenic mimicry(VM)is the formation of fluid-conducting channels by highly invasive and genetically deregulated tumor cells,enabling the tumors to form matrix-embedded vasculogenic structures,containing plasma and blood cells to meet the metabolic demands of rapidly growing tumors.In this study,we focused on DPY19L3,a C-mannosyltransferase,and aimed to unravel its role in VM.Knockout of DPY19L3 inhibited the formation of VM in HT1080 human fibrosarcoma cells.Re-expression of wild-type DPY19L3 recovered VM formation;however,DPY19L3 isoform2,an enzymatic activity-defect mutant,did not restore it,suggesting that the C-mannosyltransferase activity of DPY19L3 is crucial to its function.Furthermore,the knockdown of DPY19L3 in MDA-MB-231 breast cancer cells hindered its network formation ability.Altogether,our findings suggest that DPY19L3 is required for VM formation and stipulate the relevance of C-mannosylation in oncogenesis.展开更多
文摘C-mannosylation is a post-translational modification that occurs intracellularly in the endoplasmic reticulum.In humans,biosynthesis of C-mannosylation in proteins containing thrombospondin type 1 repeat is catalyzed by the DPY19 family;nonetheless,biological functions of protein C-mannosylation are not yet fully understood,especially in tumor progression.Vasculogenic mimicry(VM)is the formation of fluid-conducting channels by highly invasive and genetically deregulated tumor cells,enabling the tumors to form matrix-embedded vasculogenic structures,containing plasma and blood cells to meet the metabolic demands of rapidly growing tumors.In this study,we focused on DPY19L3,a C-mannosyltransferase,and aimed to unravel its role in VM.Knockout of DPY19L3 inhibited the formation of VM in HT1080 human fibrosarcoma cells.Re-expression of wild-type DPY19L3 recovered VM formation;however,DPY19L3 isoform2,an enzymatic activity-defect mutant,did not restore it,suggesting that the C-mannosyltransferase activity of DPY19L3 is crucial to its function.Furthermore,the knockdown of DPY19L3 in MDA-MB-231 breast cancer cells hindered its network formation ability.Altogether,our findings suggest that DPY19L3 is required for VM formation and stipulate the relevance of C-mannosylation in oncogenesis.