Objective To investigate the effects of TEK receptor tyrosine kinase(Tie2)L914F mutation on the biological behavior of vascular endothelial cells and the changes of related signaling pathways in patients with venous malformations.Methods Gene sequen-cing was used to detect Tie2-L914F mutations in venous malformations.HE staining and immunohistochemical staining were used to de-tect the expression of platelet derived growth factor subunit B gene(PDGFB)and α-smooth muscle actin(α-SMA)in venous malfor-mations caused by the mutation.Lentivirus overexpressing Tie2-wild type(Tie2-WT),Tie2-L914F and Tie2-GFP(green fluorescent protein,GFP)infected human umbilical vein endothelial cells(HUVECs).Real-time fluorescence quantitative PCR was used to detect the expression level of Tie2 in endothelial cells expressing exogenous Tie2 and Flag-tagged protein Tie2 protein was detected by western blotting to verify transfection efficiency.The proliferation,apoptosis,migration and tube-forming ability of the cells were determined by CCK-8,flow cytometry,Transwell migration assay and Matrigel matrix gel tube-forming assay.Western blotting was used to detect the expression levels of Protein Kinase B(PKB/AKT),FOXO1 and their phosphorylation,and the expression level of PDGFB was detec-ted by ELISA.Results The number of patients with venous malformations with L914F mutations was about 33.3％.HE and immuno-histochemical staining showed that the expressions of PDGFB and α-SMA were significantly down-regulated in venous malformation tis-sues with Tie2-L914F mutation,and were positively correlated with the decrease in cell coverage of the tube wall.Compared with Tie2-WT endothelial cells,the apoptosis number of Tie2-L914F endothelial cells was significantly reduced,while the proliferation and mi-gration ability was significantly increased,and the tube-forming ability was significantly decreased.Western blotting and ELISA showed that the phosphorylation levels of AKT and FOXO1 downstream of Tie2 signaling pathway in endothelial cells expressing Tie2-L914F were significantly increased,and the expression level of PDGFB was significantly decreased.Conclusion In venous malformations,Tie2-L914F mutation may downregulate the expression of PDGFB through AKT signaling pathway,which affects the biological behavior of vascular endothelial cells.

OBJECTIVE: To investigate the differential efficacy and safety profiles of oral mucosa (OM) grafts compared with acellular dermal matrix (ADM) grafts in the surgical management of long-segment urethral strictures. METHODS: A retrospective cohort study was conducted involving 27 patients who underwent graft urethroplasty for long-segment urethral strictures in Peking University First Hospital, spanning from May 2010 to September 2023. The patient cohort comprised 14 individuals who received OM grafts and 13 who underwent ADM grafts. The participants were stratified into two groups based on the type of grafts material utilized during surgery. The demographic and clinical baseline characteristics included an average age of (43.3±14.0) years in the OM group and (54.2±15.9) years in the ADM group. The mean body mass index (BMI) for the respective groups were (24.7±4.3) kg/m² for OM and (25.4±4.8) kg/m² for ADM. Etiological differences were noted, with idiopathic causes predominantly in the OM cohort and lichen sclerosus in the ADM cohort. RESULTS: The surgical interventions were successfully executed for all the patients. The median stricture length was 4.5 (2.5, 9.0) cm for the OM group and 5.0 (2.0, 14.0) cm for the ADM group (P=0.555). The median operative duration was 160 (71, 221) min for the OM group and 134 (112, 274) min for the ADM group (P=0.065). The catheterization durations was 1.5 (1.0, 6.0) months for the OM group and 3.0 (1.0, 3.0) months for the ADM group. The median postoperative follow-up duration was 12.5 (1.0, 170.0) months for the OM group and 59.0 (3.0, 142.0) months for the ADM group. The surgical success rates were 50.00% in the OM group and 53.85% in the ADM group. No statistically significant differences were observed in postoperative quality of life (QoL) or international prostate symptom score (IPSS) at the final follow-up. The stricture-free survival rates did not differ significantly (HR=0.875, 95%CI: 0.507-1.511, P=0.6). In terms of safety, three patients in the OM group experienced sexual dysfunction, and two had oral complications, whereas the ADM group had one case of postoperative infection. CONCLUSION The findings suggest that ADM grafts are comparable to OM grafts in terms of efficacy and safety for the treatment of long-segment urethral strictures, including complex cases attributed to lichen sclerosus. However, given the small sample size of this study, the above conclusions may have certain limitations. Larger cohort studies will be needed in the future to further validate these findings.
Humans ; Urethral Stricture/surgery* ; Acellular Dermis ; Mouth Mucosa/transplantation* ; Retrospective Studies ; Middle Aged ; Male ; Adult ; Treatment Outcome ; Skin Transplantation/methods* ; Aged

Objective To investigate the effects of TEK receptor tyrosine kinase(Tie2)L914F mutation on the biological behavior of vascular endothelial cells and the changes of related signaling pathways in patients with venous malformations.Methods Gene sequen-cing was used to detect Tie2-L914F mutations in venous malformations.HE staining and immunohistochemical staining were used to de-tect the expression of platelet derived growth factor subunit B gene(PDGFB)and α-smooth muscle actin(α-SMA)in venous malfor-mations caused by the mutation.Lentivirus overexpressing Tie2-wild type(Tie2-WT),Tie2-L914F and Tie2-GFP(green fluorescent protein,GFP)infected human umbilical vein endothelial cells(HUVECs).Real-time fluorescence quantitative PCR was used to detect the expression level of Tie2 in endothelial cells expressing exogenous Tie2 and Flag-tagged protein Tie2 protein was detected by western blotting to verify transfection efficiency.The proliferation,apoptosis,migration and tube-forming ability of the cells were determined by CCK-8,flow cytometry,Transwell migration assay and Matrigel matrix gel tube-forming assay.Western blotting was used to detect the expression levels of Protein Kinase B(PKB/AKT),FOXO1 and their phosphorylation,and the expression level of PDGFB was detec-ted by ELISA.Results The number of patients with venous malformations with L914F mutations was about 33.3％.HE and immuno-histochemical staining showed that the expressions of PDGFB and α-SMA were significantly down-regulated in venous malformation tis-sues with Tie2-L914F mutation,and were positively correlated with the decrease in cell coverage of the tube wall.Compared with Tie2-WT endothelial cells,the apoptosis number of Tie2-L914F endothelial cells was significantly reduced,while the proliferation and mi-gration ability was significantly increased,and the tube-forming ability was significantly decreased.Western blotting and ELISA showed that the phosphorylation levels of AKT and FOXO1 downstream of Tie2 signaling pathway in endothelial cells expressing Tie2-L914F were significantly increased,and the expression level of PDGFB was significantly decreased.Conclusion In venous malformations,Tie2-L914F mutation may downregulate the expression of PDGFB through AKT signaling pathway,which affects the biological behavior of vascular endothelial cells.