CircHAT1 regulates the proliferation and phenotype switch of vascular smooth muscle cells in lower extremity arteriosclerosis obliterans through targeting SFRS1.

This study aimed to decipher the mechanism of circular ribonucleic acids (circRNAs) in lower extremity arteriosclerosis obliterans (LEASO). First, bioinformatics analysis was performed for screening significantly down-regulated cardiac specific circRNA-circHAT1 in LEASO. The expression of circHAT1 in LEASO clinical samples was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression of splicing factor arginine/serine-rich 1 (SFRS1), α-smooth muscle actin (α-SMA), Calponin (CNN1), cyclin D1 (CNND1) and smooth muscle myosin heavy chain 11 (SMHC) in vascular smooth muscle cells (VSMCs) was detected by Western blotting. Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU) and Transwell assays were used to evaluate cell proliferation and migration, respectively. RNA immunoprecipitation (RNA-IP) and RNA pulldown verified the interaction between SFRS1 and circHAT1. By reanalyzing the dataset GSE77278, circHAT1 related to VSMC phenotype conversion was screened, and circHAT1 was found to be significantly reduced in peripheral blood mononuclear cells (PBMCs) of LEASO patients compared with healthy controls. Knockdown of circHAT1 significantly promoted the proliferation and migration of VSMC cells and decreased the expression levels of contractile markers. However, overexpression of circHAT1 induced the opposite cell phenotype and promoted the transformation of VSMCs from synthetic to contractile. Besides, overexpression of circHAT1 inhibited platelet-derived growth factor-BB (PDGF-BB)-induced phenotype switch of VSMC cells. Mechanistically, SFRS1 is a direct target of circHAT1 to mediate phenotype switch, proliferation and migration of VSMCs. Overall, circHAT1 regulates SFRS1 to inhibit the cell proliferation, migration and phenotype switch of VSMCs, suggesting that it may be a potential therapeutic target for LEASO.

Managing Emergent Surgery for Ruptured Abdominal Aortic Aneurysm during the COVID-19 Pandemic.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has become a global pandemic which may compromise the management of vascular emergencies. An uncompromised treatment for ruptured abdominal aortic aneurysm (rAAA) during such a health crisis represents a challenge. This study aimed to demonstrate the treatment outcomes of rAAA and the perioperative prevention of cross-infection under the COVID-19 pandemic. METHODS: In cases of rAAA during the pandemic, a perioperative workflow was applied to expedite coronavirus testing and avoid pre-operative delay, combined with a strategy for preventing cross-infection. Data of rAAA treated in 11 vascular centers between January-March 2020 collected retrospectively were compared to the corresponding period in 2018 and 2019. RESULTS: Eight, 12, and 14 rAAA patients were treated in 11 centers in January-March 2018, 2019, and 2020, respectively. An increased portion were treated at local hospitals with a comparable outcome compared with large centers in Guangzhou. With EVAR-first strategy, 85.7% patients with rAAA in 2020 underwent endovascular repair, similar to that in 2018 and 2019. The surgical outcomes during the pandemic were not inferior to that in 2018 and 2019. The average length of ICU stay was 1.8 ± 3.4 days in 2020, tending to be shorter than that in 2018 and 2019, whereas the length of hospital stay was similar among 3 years. The in-hospital mortality of 2018, 2019, and 2020 was 37.5%, 25.0%, and 14.3%, respectively. Three patients undergoing emergent surgeries were suspected of COVID-19, though turned out to be negative after surgery. CONCLUSIONS: Our experience for emergency management of rAAA and infection prevention for healthcare providers is effective in optimizing emergent surgical outcomes during the COVID-19 pandemic.

miR-21 regulates vascular smooth muscle cell function in arteriosclerosis obliterans of lower extremities through AKT and ERK1/2 pathways.

INTRODUCTION: Arteriosclerosis obliterans (ASO) is a disease that affects the lower extremities. The mechanism of ASO is associated with the proliferation and migration of vascular smooth muscle cells (VSMCs). miR-21 plays a key role in various biological processes of the cardiovascular system, associated with the proliferation, migration and apoptosis of VSMCs. It is unclear, however, if miR-21 is involved in the regulation of ASO. MATERIAL AND METHODS: Human aortic smooth muscle cells (HASMCs) were transfected with miR-21 mimics and co-treated with protein kinase B (AKT) or a mitogen-activated protein kinase (ERK) inhibitor. Expression levels of p-AKT or p-ERK were measured by western blot. Cell apoptosis was assessed using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay and visualized under a fluorescence microscope. Cell proliferation was monitored by bromodeoxyuridine (BrdU) labeling; cell migration and invasion were determined by the Transwell assay. RESULTS: miR-21 was upregulated in arteries of ASO, the pathogenesis of which involved the activation of p-AKT and p-ERK1/2. Inhibition of the AKT or ERK activity was consistent with the attenuation of the miR-21-induced HASMC migration and proliferation. HASMCs co-treated with miR-21 mimics and AKT or ERK inhibitor showed attenuation of the miR-21-induced high elongation ratio. CONCLUSIONS: We demonstrated that the expression of miR-21 in HASMCs could find potential application in cardiac therapy. Inhibition of the activity of AKT or ERK could attenuate miR-21-induced cell proliferation and migration as well as altering morphology of HASMCs. The present study aimed to indicate the potential roles of miR-21 in ASO processes, and the results provided a novel therapeutic approach for treating ASO and new targets for preventing ASO in earlier stages.

Activation of NLRP3 Inflammasome Promotes Foam Cell Formation in Vascular Smooth Muscle Cells and Atherogenesis Via HMGB1.

Background This study aimed at investigating whether NLRP 3 (the Nod like receptor family, pyrin domain-containing 3 protein) inflammasome activation induced HMGB 1 (high mobility group box-1 protein) secretion and foam cell formation in human vascular smooth muscle cells ( VSMC s) and atherosclerosis in ApoE-/- mice. Methods and Results VSMC s or ApoE-/- mice were treated with lipopolysaccharides ( LPS ) and/or ATP or LPS and high-fat diet to induce NLRP 3 inflammasome activation. HMGB 1 distribution and foam cell formation in VSMC s were characterized. Liver X receptor α and ATP -binding cassette transporter expression were determined. The impact of NLRP 3 or receptor for advanced glycation end product silencing, ZYVAD - FMK (caspase-1 inhibitor), glycyrrhizin ( HMGB 1 inhibitor) or receptor for advanced glycation end product antagonist peptide on HMGB 1 secretion, foam cell formation, liver X receptor α and ATP -binding cassette transporter expression was examined. Expression level of HMGB 1 in human atherosclerosis obliterans arterial tissues was characterized. Our results found that NLRP 3 inflammasome activation promoted foam cell formation and HMGB 1 secretion in VSMC s. Extracellular HMGB 1 was a key signal molecule in inflammasome activation-mediated foam cell formation. Furthermore, inflammasome activation-induced HMGB 1 activity and foam cell formation were achieved by receptor for advanced glycation end product/liver X receptor α / ATP -binding cassette transporter glycyrrhizin. Experiments in vivo found glycyrrhizin significantly attenuated the LPS /high-fat diet-induced atherosclerosis and serum HMGB 1 levels in mice. Finally, levels of HMGB 1 and NLRP 3 were increased in tunica media adjacent to intima of atherosclerosis obliteran arteries. Conclusions Our results revealed that HMGB1 is a key downstream signal molecule of NLRP 3 inflammasome activation and plays an important role in VSMC s foam cell formation and atherogenesis by downregulating liver X receptor α and ATP -binding cassette transporter expression through receptor for advanced glycation end product.

MicroRNA-31 promotes arterial smooth muscle cell proliferation and migration by targeting mitofusin-2 in arteriosclerosis obliterans of the lower extremitie.

MicroRNA (miR)-31 serves a key role in various biological processes, including tumor development, angiogenesis and inflammation. Whether miR-31 is involved in the pathological processes of arteriosclerosis obliterans (ASO) remains to be elucidated, as does the mechanism of miR-31 regulation of arterial smooth muscle cells (ASMCs). In the present study, miR-31 expression was detected by reverse transcription-quantitative polymerase chain reaction and in situ hybridization, and was significantly upregulated in human ASO arterial walls compared with normal arterial walls (P<0.001). In addition, miR-31 proliferation was detected by Cell Counting Kit-8 and EdU assays; proliferation was significantly promoted in platelet-derived growth factor (PDGF)-BB-induced human ASMCs (HASMCs) (P<0.001). miR-31 migration was detected by transwell and wound closure assays, and was revealed to be promoted in PDGF-BB-induced HASMCs (P<0.001). Lastly, HASMCs were transfected with miR-31 mimics and inhibitors, and negative controls. A dual-luciferase reporter assay was performed to verify that mitofusin-2 (MFN2) was a direct target of miR-31 and that MFN2 expression was significantly downregulated by miR-31 at a post-transcriptional level in HASMCs as detected by western blotting (P<0.01). These findings suggest that miR-31 is able to promote the proliferation and migration of HASMCs, at least in part, by targeting MFN2. The results of the present study provide novel insight into the underlying mechanisms and roles of miR-31/MFN2 in the pathology of ASO, which may offer a potential therapeutic target for the treatment of ASO.

[Carotid artery stenosis treated with modified carotid endarterectomy: report of two cases].

OBJECTIVE: Based on standard carotid endarterectomy, we performed modified carotid endarterectomy in two cases of carotid artery stenosis by changing the direction of the carotid artery incision to avoid restenosis of the internal carotid artery without using a patch. The two patients recovered smoothly without any complications. Compared with eversion or patch endarterectomy, this modified carotid endarterectomy avoids restenosis of the carotid artery and shortens operation time.

Mir-22-3p Inhibits Arterial Smooth Muscle Cell Proliferation and Migration and Neointimal Hyperplasia by Targeting HMGB1 in Arteriosclerosis Obliterans.

BACKGROUND: Aberrant vascular smooth muscle cell (VSMC) proliferation and migration contribute to the development of vascular pathologies, such as atherosclerosis and post-angioplasty restenosis. The aim of this study was to determine whether miR-22-3p plays a role in regulating human artery vascular smooth muscle cell (HASMC) function and neointima formation. METHODS: Quantitative real-time PCR (qRT-PCR) and fluorescence in situ hybridization (FISH) were used to detect miR-22-3p expression in human arteries. Cell Counting Kit-8 (CCK-8) and EdU assays were performed to assess cell proliferation, and transwell and wound closure assays were performed to assess cell migration. Moreover, luciferase reporter assays were performed to identify the target genes of miR-22-3p. Finally, a rat carotid artery balloon-injury model was used to determine the role of miR-22-3p in neointima formation. RESULTS: MiR-22-3p expression was downregulated in arteriosclerosis obliterans (ASO) arteries compared with normal arteries, as well as in platelet-derived growth factor-BB (PDGF-BB)-stimulated HASMCs compared with control cells. MiR-22-3p overexpression had anti-proliferative and anti-migratory effects and dual-luciferase assay showed that high mobility group box-1 (HMGB1) is a direct target of miR-22-3p in HASMCs. Furthermore, miR-22-3p expression was negatively correlated with HMGB1 expression in ASO tissue specimens. Finally, LV-miR-22-3p-mediated miR-22-3p upregulation significantly suppressed neointimal hyperplasia specifically by reducing HMGB1 expression in vivo. CONCLUSIONS: Our results indicate that miR-22-3p is a key molecule in regulating HASMC proliferation and migration by targeting HMGB1 and that miR-22-3p and HMGB1 may be therapeutic targets in the treatment of human ASO.

HMOX-1 inhibits TGF-ß-induced epithelial-mesenchymal transition in the MCF-7 breast cancer cell line.

Epithelial­mesenchymal transition (EMT) is a key mechanism underlying metastatic breast cancer. Reactive oxygen species (ROS) play an important role in EMT. Heme oxygenase­1 (HMOX­1) can reduce oxidative stress. However, the effect of HMOX­1 on the EMT process in breast cancer cells is unknown. We treated the MCF­7 breast cancer cell line with the HMOX­1 inducer hemin and observed that hemin induced HMOX­1 expression and inhibited migration, invasion and ROS generation in transforming growth factor­ß (TGF­ß)­treated MCF­7 cells using quantitative RT­qPCR, western blotting, wound­healing and cell invasion assays as well as fluorescent probe DCFDA. Hemin inhibited TGF­ß­induced EMT in the MCF­7 cells, whereas HMOX­1 siRNA attenuated the suppressive effect of hemin as determined by the expression and cellular distribution of selected EMT markers. In summary, our results revealed that hemin treatment increased HMOX­1 expression and inhibited TGF­ß­induced EMT in MCF­7 cells.

The role of vascular epithelial growth factor receptor-tyrosine kinase inhibitors in the treatment of advanced breast cancer: a meta-analysis of 12 randomized controlled trials.

AIM: To perform a systematic review and meta-analysis of randomized controlled trials to determine the efficacy and toxicity of approved vascular epithelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKIs) in advanced breast cancer. METHODS: A comprehensive literature search for studies published up to August 2013 was performed. The endpoints were overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and grade 3 or 4 adverse event (AEs). The pooled hazard ratio (HR) or relative risk (RR), and 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials. RESULTS: Twelve randomized controlled trials involved 3256 patients were ultimately identified. The intention to treatment (ITT) analysis demonstrated that VEGFR-TKI therapy significantly improved ORR (RR 1.14, 95% CI: 1.03-1.28, p = 0.016), but it did not translate into benefits in PFS (HR 0.99, 95% CI: 0.81-1.22, p = 0.93) and OS (HR 1.11, 95% CI 0.99-1.24, p = 0.084) when compared to non-VEGFR-TKI therapy. Additionally, a higher incidence of grade 3 or 4 anemia, neutropenia, thrombocytopenia, diarrhea, hand-foot syndrome and fatigue was observed in VEGFR-TKI-based therapy. CONCLUSIONS: The VEGFR-TKI-based therapy offered a significant improvement in ORR in patients with advanced breast cancer but did not benefit PFS and OS. With present available data from randomized clinical trials, we were still unable to clearly set the role of VEGFR-TKIs in the treatment of metastatic breast cancer (MBC).