Effects of propranolol on glucose metabolism in hemangioma-derived endothelial cells.

Infantile hemangioma (IH) is the most common benign tumor in children. Propranolol is the first-line treatment for IH, but the underlying mechanism of propranolol treatment in IH is not completely understood. Integrated transcriptional and metabolic analyses were performed to investigate the metabolic changes in hemangioma-derived endothelial cells (HemECs) after propranolol treatment. The findings were then further validated through independent cell experiments using a Seahorse XFp analyzer, Western blotting, immunohistochemistry and mitochondrial functional assays. Thirty-four differentially expressed metabolites, including the glycolysis metabolites glucose 6-phosphate, fructose 6-phosphate and fructose 1,6-bisphosphate, were identified by targeted metabolomics. A KEGG pathway enrichment analysis showed that the disturbances in these metabolites were highly related to glucose metabolism-related pathways, including the pentose phosphate pathway, the Warburg effect, glycolysis and the citric acid cycle. Transcriptional analysis revealed that metabolism-related pathways, including glycine, serine and threonine metabolism, tyrosine metabolism, and glutathione metabolism, were highly enriched. Moreover, integration of the metabolomic and transcriptomic data revealed that glucose metabolism-related pathways, particularly glycolysis, were altered after propranolol treatment. Cell experiments demonstrated that HemECs exhibited higher levels of glycolysis than human umbilical vein ECs (HUVECs) and that propranolol suppressed glycolysis in HemECs. In conclusion, propranolol inhibited glucose metabolism in HemECs by suppressing glucose metabolic pathways, particularly glycolysis.

M2 Macrophage-Derived Exosomal lncRNA MIR4435-2HG Promotes Progression of Infantile Hemangiomas by Targeting HNRNPA1.

Purpose: Infantile hemangiomas (IHs) are commonly observed benign tumors that can cause serious complications. M2-polarized macrophages in IHs promote disease progression. In this study, we investigated the role of M2 macrophage-derived exosomal lncRNA MIR4435-2HG in IHs. Patients and Methods: Exosomes derived from M2 polarized macrophages were extracted. Next, using cell co-culture or transfection, we investigated whether M2 polarized macrophage-derived exosomes (M2-exos) can transport MIR4435-2HG to regulate the proliferation, migration, invasion, and angiogenesis of hemangioma-derived endothelial cells (HemECs). RNA-seq and RNA pull-down assays were performed to identify targets and regulatory pathways of MIR4435-2HG. We explored the possible mechanisms through which MIR4435-2HG regulates the biological function of HemECs. Results: M2-exos significantly enhanced the proliferation, migration, invasion, and angiogenesis of HemECs. Thus, HemECs uptake M2-exos and promote biological functions through the inclusion of MIR4435-2HG. RNA-seq and RNA pull-down experiments confirmed that MIR4435-2HG regulates of HNRNPA1 expression and directly binds to HNRNPA1, consequently affecting the NF-κB signal pathway. Conclusion: MIR4435-2HG of M2-exos promotes the progression of IHs and enhances the proliferation, migration, invasion, and angiogenesis of HemECs by directly binding to HNRNPA1. This study not only reveals the mechanism of interaction between M2 macrophages and HemECs, but also provides a promising therapeutic target for IHs.

Integrated nontargeted and targeted metabolomics analyses amino acids metabolism in infantile hemangioma.

Infantile hemangioma (IH) is the most common benign tumor in children. However, the exact pathogenesis of IH remains unclear. Integrated nontargeted and targeted metabolic analyses were performed to obtain insight into the possible pathogenic mechanism of IH. The results of nontargeted metabolic analysis showed that 216 and 128 differential metabolites (DMs) were identified between hemangioma-derived endothelial cells (HemECs) and HUVECs in positive-ion and negative-ion models, respectively. In both models, these DMs were predominantly enriched in pathways related to amino acid metabolism, including aminoacyl-tRNA biosynthesis and arginine and proline metabolism. Then, targeted metabolic analysis of amino acids was further performed to further clarify HemEC metabolism. A total of 22 amino acid metabolites were identified, among which only 16 metabolites, including glutamine, arginine and asparagine, were significantly differentially expressed between HemECs and HUVECs. These significant amino acids were significantly enriched in 10 metabolic pathways, including 'alanine, aspartate and glutamate metabolism', 'arginine biosynthesis', 'arginine and proline metabolism', and 'glycine, serine and threonine metabolism'. The results of our study revealed that amino acid metabolism is involved in IH. Key differential amino acid metabolites, including glutamine, asparagine and arginine, may play an important role in regulating HemEC metabolism.

Effects of the key glycolytic enzyme PFKFB3 on the proliferation, migration and apoptosis of hemangioma-derived endothelial cells / 中华皮肤科杂志

Objective:To investigate the effect of the key glycolysis enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) on the biological activity of hemangioma-derived endothelial cells (HemECs) .Methods:Totally, 4 proliferating infantile hemangioma (IH) tissues and 4 involuting IH tissues were collected. Primary HemECs were isolated from the proliferating IH tissues, and human umbilical vein endothelial cells (HUVECs) served as controls. Immunohistochemical study and Western blot analysis were performed to determine the expression of PFKFB3 in the IH tissues and HemECs, respectively. Cell counting kit-8 (CCK8) assay was conducted to evaluate the effect of PFK15 (a specific inhibitor of PFKFB3) at concentrations of 0 - 10 μmol/L on the proliferation of HemECs, and HemECs treated without PFKFB3 served as the control group. Some in vitro cultured HemECs were treated with 5 μmol/L PFK15, and served as a PFK15 intervention group, while HemECs treated without PFK15 served as a control group; then, the migratory ability of HemECs was assessed by Transwell assay, and the apoptosis level of HemECs was detected by flow cytometry. Comparisons between groups were performed by using t test or analysis of variance. Results:Immunohistochemical study showed that the positive rate of PFKFB3 was significantly higher in the proliferating IH tissues (74.34% ± 5.26%) than in the involuting IH tissues (41.46% ± 2.99%, t = 9.40, P < 0.001). Western blot analysis showed that the relative expression level of PFKFB3 was also significantly higher in HemECs (0.73 ± 0.05) than in HUVECs (0.45 ± 0.04, t = 8.50, P < 0.001). CCK8 assay revealed significantly decreased proliferative activity of HemECs in the 0.625-, 1.25-, 2.5-, 5-, and 10-μmol/L PFK15 groups compared with the control group (all P < 0.01). Compared with the control group, the PFK15 intervention group showed significantly decreased number of migratory HemECs (297 ± 15 vs. 422 ± 8, t = 12.59, P < 0.001), but significantly increased apoptosis rates of HemECs (6.69% ± 0.64% vs. 0.34% ± 0.07%, t = 17.07, P < 0.001) . Conclusion:The key glycolytic enzyme PFKFB3 was highly expressed in the proliferating IH tissues and HemECs, and the PFKFB3 inhibitor PFK15 could suppress the proliferation, migration, and increase the apoptosis of HemECs.