Facial cutaneo-mucosal venous malformations can develop independently of mutation of TEK gene but may be associated with excessive expression of Src and p-Src

Effect and mechanism of apelin on lipopolysaccharide induced acute pulmonary vascular endothelial barrier dysfunction

Vascular endothelial barrier dysfunction is the most prominent manifestation and important cause of mortality in infectious acute lung injury (ALI). Exogenous apelin is effective in ameliorating lipopolysaccharide (LPS)-induced inflammatory response in ALI lungs, reducing exudation of lung tissue and decreasing mortality. This study set out to investigate the association between apelin and Friend leukemia integration-1 (Fli-1) in the prevention and treatment of ALI, and to elucidate the molecular mechanism by which apelin protects the permeability of the vascular endothelial barrier. At the vivo functional level, lung wet/dry weight ratio was used to detect whole lung permeability, evans blue assay and dual fluorescent protein tracking assay were used to detect lung vascular endothelial permeability, HE staining to observe the inflammatory status of lung tissue, and immunofluorescence staining for VE-cadherin expression levels in blood vessels. The changes in inflammatory factors in bronchoalveolar lavage fluid (BALF) were detected by ELASA. Western blot was used to detect the expression level of proteins. qRT-PCR was performed to detect changes in mRNA expression of Fli-1 and adherent junction-related proteins. The correlation analysis of Fli-1 with vascular endothelial permeability and SRC showed that Fli-1 participated in the process of ALI. After preventive and therapeutic treatment of ALI mice with exogenous apelin, Fli-1, APJ, VE-cadherin, phosphorylated-VE-cadherin (p-VE-cadherin) and β-catenin were up-regulated, while SRC, phosphorylated-SRC (p-SRC), VEGF and VEGF-R were down-regulated, which indicated that the stability of vascular endothelial barrier was enhanced. With the use of Fli-1 inhibitor irinotecan, the protective effect of apelin was weakened in various functional indexes, genes and proteins. The lung was maintained at the level of the injury. Our research shows that Fli-1 is involved in the LPS-induced ALI process. The molecular mechanism for apelin in preventing endothelial barrier dysfunction in ALI is through up-regulating Fli-1, thus regulating adherens junction-related proteins, and finally recovering the endothelial barrier function.

Anticancer Activity of Leonurus sibiricus L.: Possible Involvement of Intrinsic Apoptotic Pathway

Liver cancer is the most common cause of mortality in men and women. The aim of this study was to evaluate the methanolic extract of aerial parts of Leonurus sibiricus L (LS) for its anticancer activity on HCC cell lines. Human HCC cell lines, Huh-7 and HSC-T6 were used for cytotoxicity assay, determination of ROS and gene expression analysis (p53, Bcl-2, Bax, caspase-3, caspase-8, and caspase-9). Western blotting was used to assess ERK, AKT, and Caspase-3 activation. HPLC-MS analysis was also performed to determine the phytochemicals present in LS-M extract. LS-M extract has increased the expression of proapoptotic genes, including p53, Bax, and caspase-9 and down-regulated the activation of ERK and Akt. The caspase-3 activity as well as the ROS generation were significantly increased in a dose-dependent manner compared to control. The carotenoids, lutein and beta carotene present in LS-M extract exhibited anticancer activity. In overall, the methanolic extract of LS induces apoptosis in Huh-7 as well as in HSC-T6 cells possibly involving a ROS-mediated mitochondrial signaling pathway.

MET somatic activating mutations are responsible for lymphovenous malformation and can be identified using cell-free DNA next generation sequencing liquid biopsy

OBJECTIVE

Germline mutations of either the endothelial cell-specific tyrosine kinase receptor TIE2 or the glomulin (GLMN) gene are responsible for rare inherited venous malformations. Both genes affect the hepatocyte growth factor receptor c-Met, inducing vascular smooth muscle cell migration. Germline mutations of hepatocyte growth factor are responsible for lymphatic malformations, leading to lymphedema. The molecular alteration leading to the abnormal mixed vascular anomaly defined as lymphovenous malformation has remained unknown.

METHODS

A group of 4 patients with lymphovenous malformations were selected. Plasma was obtained from both peripheral and efferent vein samples at the vascular malformation site for cell-free DNA extraction. When possible, we analyzed tissue biopsy samples from the vascular lesion.

RESULTS

We have demonstrated that in all four patients, an activating MET mutation was present. In three of the four patients, the same pathogenic activating mutation, T1010I, was identified. The mutation was found at the tissue level for the patient with tissue samples available, confirming its causative role in the lymphovenous malformations.

CONCLUSIONS

In the present study, we have demonstrated that cell-free DNA next generation sequencing liquid biopsy is able to identify the MET mutations in affected tissues. Although a wider cohort of patients is necessary to confirm its causative role in lymphovenous malformations, these data suggest that lymphovenous malformations could result from postzygotic somatic mutations in genes that are key regulators of lymphatic development. The noninvasiveness of the method avoids any risk of bleeding and can be easily performed in children. We are confident that the present pioneering results have provided a viable alternative in the future for lymphovenous malformation diagnosis, allowing for subsequent therapy tailored to the genetic defect.