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Backgrounds: Nei endonuclease VIII-like 3 (NEIL3), a novel tumor-related gene, was differentially expressed and involved in pathophysiological processes in multiple tumors. However, the potential biological functions and molecular mechanisms of NEIL3 in human clear cell renal cell carcinoma (ccRCC) have not been identified.Methods The expression pattern and prognostic value of NEIL3 in ccRCC patients were analyzed in multiple comprehensive databases and validated by qRT-PCR, western blotting analysis, immunohistochemistry, and tissue chips. The regulatory mechanisms were verified by the GSEA analysis, chromatin immunoprecipitation, dual-luciferase reporter gene, and immunofluorescence assay. The oncogenic effect of NEIL3 in ccRCC was confirmed by MTT assay, colony formation assay, tumorsphere assay, cell flow cytometry analysis, and xenograft tumor models.Results Nei endonuclease VIII-like 3 (NEIL3), a novel tumor-related gene, was highly expressed in ccRCC and positively correlated with adverse clinicopathological characteristics and worse prognosis. Mechanistically, we demonstrated that NEIL3 promoted cell proliferation and cell cycle progression in vitro and tumor growth in vivo. Furthermore, we found that NEIL3 overexpression activated the cyclin D1-Rb-E2F1 pathway. The E2F1 elevation then promoted the proliferation, cell cycle transition, and the NEIL3 expression, thus forming a feedback loop of the NEIL3-E2F1 axis to contribute to ccRCC progression. In addition, there was a positive correlation between NEIL3 and E2F1 expression in clinical specimens of ccRCC.Conclusion NEIL3 and cyclin D1-Rb-E2F1 pathway form a positive feedback loop and coordinately contribute to ccRCC progression. NEIL3 presents as a novel candidate for ccRCC diagnosis and treatment.

The aim of this study was to explore the role of ILK in an in vitro model of diabetic cardiomyopathy. We used 30 mmol/L high glucose to treat H9C2 cells to construct an in vitro model, knocked down the ILK expression level of H9C2 cells by small interference technology, and detected the activity of antioxidant enzymes and inflammatory factors in the supernatant. The expression levels of SOD1 and IL-1β were detected by immunofluorescence staining. The expression levels of the TLR4/MyD88/NF-κB signaling pathway and its downstream factors were detected by quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Compared with the control group, after high-glucose culture of H9C2 cells, the cell activity decreased, while the apoptosis rate increased, with the TLR4/MyD88/NF-κB signaling pathway activated, thereby inducing oxidative stress and inflammation. Compared with the high-glucose group, the HG+si-ILK group increased cell activity, decreased the apoptosis rate, and inhibited the excessive activation of the TLR4/MyD88/NF-κB signaling pathway, thereby improving oxidative stress and inflammation. Knockdown of ILK expression can protect H9C2 cells from reducing high glucose-induced inflammation, oxidative stress, and apoptosis by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

OBJECTIVE To determine the risk for pulmonary embolism (PE) and explore the relationship between the site of thrombosis and PE in patients with acute lower extremity deep vein thrombosis (DVT). METHODS 1585 hospitalized patients first diagnosed with acute lower extremity DVT were investigated retrospectively. The patients were divided into two groups: the non-PE group (Group 1) and the PE group (Group 2). Then, Group 2 was divided into two subgroups: asymptomatic pulmonary embolism (asPE, Group 2a) and symptomatic pulmonary embolism (sPE, Group 2b). Kaplan-Meier curves and logistic regression analysis were used to explore the relevant risk factors for PE. RESULTS Among 1585 patients, 458 patients suffered from PE, accounting for 28.9%. 102 (22.3%) of them had the typical clinical manifestations of PE and were defined as sPE, and the remaining 356 (77.7%) patients were classified as asPE. Patients with proximal lower extremity DVT were significantly more predominant in the PE group than in the non-PE group (92.8% vs. 86.2%, p

Related Article from Fluorescence Resonance Energy Transfer Biosensors for Cancer Detection and Evaluation of Drug Efficacy

Objective The vital pathogenesis of varicose veins includes remodeling of the extracellular matrix and decreased vascular tone. Prostaglandin E2 (PGE2), a small molecule substance and inflammatory medium that belongs to the arachidonic acid derivatives, has the capacity to influence the expression of metalloproteinase and the vascular tone of the venous wall. The purpose of the present study was to investigate the role of PGE2 in the development of varicose veins in lower limbs. Methods The collected venous specimens were analyzed using hematoxylin and eosin, Masson's trichrome, and immunohistochemical staining. Transforming growth factor (TGF)-β1, PGE2, CD31, and α-smooth muscle actin antibody were used to detect the expression and distribution of these proteins. The effect of PGE2 on the proliferation, migration, and tube formation capacity of human umbilical vein endothelial cells (HUVECs) was detected in vitro. The effect of TGF-β1 on the expression of PGE2 and matrix metalloproteinases (MMPs) was assessed using Western blotting. Quantitative reverse transcription polymerase chain reaction was used to evaluate the effect of PGE2 on the expression of nitric oxide synthase (NOS) and other genes. Results The expression of PGE2 and TGF-β1 in varicose veins was upregulated in the media tunica and intima tunica, and a strong positive correlation was found between PGE2 and TGF-β1 expression in both varicose veins (95% confidence interval, 0.5207-0.9582; R = 0.848; P = .0005) and normal veins (95% confidence interval, 0.2530-0.8532; R = 0.643; P = .003). PGE2 promoted the migration and tube formation ability of HUVECs. Moreover, PGE2 also upregulated the expression of MMP-1 and TGF-β1 in HUVECs and increased the mRNA level of inducible NOS. Conclusions PGE2 can affect the remodeling of the extracellular matrix and reduce the elasticity of the vascular walls by promoting the synthesis of TGF-β1 and MMP-1. PGE2 can also reduce the tension of the great saphenous vein by promoting the expression of inducible NOS, thus aggravating the blood stasis.

Background Adipose-derived mesenchymal stem cells (ADSC)-based therapy is an outstanding treatment strategy for ischaemic disease. However, the therapeutic efficacy of this strategy is not ideal due to the poor paracrine function and low survival rate of ADSCs in target regions. Platelet extracellular vesicles (PEVs) are nanoparticles derived from activated platelets that can participate in communication between cells. Accumulating evidence indicates that PEVs can regulate the biological functions of several cell lines. In the present study, we aimed to investigate whether PEVs can modulate the proangiogenic potential of ADSCs in vitro and in vivo. Methods PEVs were identified using scanning electron microscope (SEM), flow cytometry (FCM) and nanoparticle tracking analysis (NTA). The CCK8 assay was performed to detect proliferation of cells. Transwell and wound healing assays were performed to verify migration capacity of cells. AnnexinV-FITC/PI apoptosis kit and live/dead assay were performed to assess ADSCs apoptosis under Cocl2-induced hypoxia condition. The underlying mechanisms by which PEVs affected ADSCs were explored using real time-PCR(RT-PCR) and Western blot. In addition, matrigel plug assays were conducted and mouse hindlimb ischaemic models were established to investigate the proangiogenic potential of PEV-treated ADSCs in vivo. Results We demonstrated that ADSC could internalize PEVs, which lead to a series of biological reactions. In vitro, dose-dependent effects of PEVs on ADSC proliferation, migration and antiapoptotic capacity were observed. Western blotting results suggested that multiple proteins such as ERK, AKT, FAK, Src and PLCγ1 kinase may contribute to these changes. Furthermore, PEVs induced upregulation of several growth factors expression in ADSCs and amplified the proliferation, migration and tube formation of HUVECs induced by ADSC conditioned medium (CM). In in vivo experiments, compared with control ADSCs, the injection of PEV-treated ADSCs resulted in more vascularization in matrigel plugs, attenuated tissue degeneration and increased blood flow and capillary density in ischaemic hindlimb tissues. Conclusion Our data demonstrated that PEVs could enhance the proangiogenic potential of ADSCs in mouse hindlimb ischaemia. The major mechanisms of this effect included the promotion of ADSC proliferation, migration, anti-apoptosis ability and paracrine secretion.

Supplemental Digital Content is available in the text., In our previous studies, we found that T24 lung metastatic cancer cells showed high invasion and metastasis abilities and cancer stem cell characteristics compared with T24 primary cancer cells. By screening for the expression of CXC chemokines in both cell lines, we found that CXCL5 is highly expressed in T24-L cells. The aim of this study is to shed light on the relationship of CXCL5 with epithelial–mesenchymal transition (EMT) and cancer stem cells (CSCs). RNAi technology was used to decrease CXCL5 expression in the T24-L cell line, and the EMT and CSCs of the shCXCL5 group and the control group were compared. The CXCR2 inhibitor SB225002 was used to inhibit the receptor of CXCL5 to determine the effect of the CXCL5/CXCR2 axis. The knockdown of CXCL5 expression in T24-L cells reduced their EMT and CSC characteristics. RT-PCR and Western blot analyses revealed the downregulation of N-cadherin, Vimentin and CD44. In addition, when CD44 expression was knocked down, the EMT ability of the cells was also inhibited. This phenomenon was most pronounced when both CXCL5 and CD44 were knocked down. CXCL5 and CD44 can affect the EMT and stem cell capacity of T24-L cells through some interaction.

The limited sensitivity of Förster Resonance Energy Transfer (FRET) biosensors hinders their broader applications. Here, we develop an approach integrating high-throughput FRET sorting and next-generation sequencing (FRET-Seq) to identify sensitive biosensors with varying substrate sequences from large-scale libraries directly in mammalian cells, utilizing the design of self-activating FRET (saFRET) biosensor. The resulting biosensors of Fyn and ZAP70 kinases exhibit enhanced performance and enable the dynamic imaging of T-cell activation mediated by T cell receptor (TCR) or chimeric antigen receptor (CAR), revealing a highly organized ZAP70 subcellular activity pattern upon TCR but not CAR engagement. The ZAP70 biosensor elucidates the role of immunoreceptor tyrosine-based activation motif (ITAM) in affecting ZAP70 activation to regulate CAR functions. A saFRET biosensor-based high-throughput drug screening (saFRET-HTDS) assay further enables the identification of an FDA-approved cancer drug, Sunitinib, that can be repurposed to inhibit ZAP70 activity and autoimmune-disease-related T-cell activation., Existing Förster Resonance Energy Transfer (FRET) biosensors are often limited in their sensitivity. Here the authors report FRET-seq which they use to identify Fyn and ZAP70 kinase biosensors with enhanced performance, and use them to image T-cell activation and screen drugs.

Piezo1 belongs to mechano-activatable cation channels serving as biological force sensors. However, the molecular events downstream of Piezo1 activation remain unclear. In this study, we used biosensors based on fluorescence resonance energy transfer (FRET) to investigate the dynamic modes of Piezo1-mediated signaling and revealed a bimodal pattern of Piezo1-induced intracellular calcium signaling. Laser-induced shockwaves (LIS) and its associated shear stress can mechanically activate Piezo1 to induce transient intracellular calcium (Ca[i]) elevation, accompanied by an increase in FAK activity. Interestingly, multiple pulses of shockwave stimulation caused a more sustained calcium increase and a decrease of FAK activity. Similarly, tuning the degree of Piezo1 activation by titrating either the dosage of Piezo1 ligand Yoda1 or the expression level of Piezo1, produced a similar bimodal pattern of FAK responses. Specifically, a low degree of Piezo1 activation (transient mode) leads to a transient Ca[i] response with FAK activation, whereas a high degree of Piezo1 activation (sustained mode) causes a sustained Ca[i] response with FAK suppression. Further investigation revealed that SHP2 serves as an intermediate regulator mediating this bimodal pattern in Piezo1 sensing and signaling. These results suggest that the degrees of Piezo1 activation induced by both mechanical LIS and chemical ligand stimulation may determine downstream signaling characteristics.

Understanding the connection between the topology of a biochemical reaction network and its dynamical behavior is an important topic in systems biology. We proved a no-oscillation theorem for the transient dynamics of the linear signal transduction pathway, that is, there are no dynamical oscillations for each species if the considered system is a simple linear transduction chain equipped with an initial stimulation. In the nonlinear case, we showed that the no-oscillation property still holds for the starting and ending species, but oscillations generally exist in the dynamics of intermediate species. We also discussed different generalizations on the system setup. The established theorem will provide insights on the understanding of network motifs and the choice of mathematical models when dealing with biological data.

Therapeutic angiogenesis by transplantation of autologous/allogeneic adipose stem cells (ADSCs) is a potential method for the treatment of critical limb ischemia (CLI). However, the therapeutic efficiency is limited by poor viability, adhesion, migration and differentiation after cell transplantation into the target area. Astragaloside IV (AS-IV), one of the main active components of Astragalus, has been widely used in the treatment of ischemic diseases and can promote cell proliferation and angiogenesis. However, there is no report on the effect of AS-IV on ADSCs and its effect on hindlimb ischemia through cell transplantation.The purpose of this study was to elucidate that AS-IV pretreatment enhances the therapeutic effect of ADSC on critical limb ischemia, and to characterize the underlying molecular mechanisms.ADSCs were obtained and pretreated with the different concentration of AS-IV. In vitro, we analyzed the influence of AS-IV on ADSC proliferation, migration, angiogenesis and recruitment of human umbilical vein endothelial cells (HUVECs) and analyzed the relevant molecular mechanism. In vivo, we injected drug-pretreated ADSCs into a Matrigel or hindlimb ischemia model and evaluated the therapeutic effect by the laser Doppler perfusion index, immunofluorescence, and histopathology.In vitro experiments showed that AS-IV improved ADSC migration, angiogenesis and endothelial recruitment. The molecular mechanism may be related to the upregulation of CXC receptor 2 (CXCR2) to promote the phosphorylation of focal adhesion kinase (FAK). In vivo, Matrigel plug assay showed that ADSCs pretreated with AS-IV have stronger angiogenic potential. The laser Doppler perfusion index of the hindlimbs of mice in the ADSC/AS-IV group was significantly higher than the laser Doppler perfusion index of the hindlimbs of mice of the ADSC group and the control group, and the microvessel density was significantly increased.Our results demonstrate that AS-IV pretreatment of ADSC improves their therapeutic efficacy in ameliorating severe limb exclusion symptomology through CXCR2 induced FAK phosphorylation, which will bring new insights into the treatment of severe limb ischemia.

Genetically-encoded biosensors based on FRET have been widely used to dynamically monitor the activity of protein tyrosine kinases (PTKs) in living cell with high spatiotemporal resolution. However, the limitation in sensitivity, specificity, and dynamic range of FRET biosensors have hindered their broader applications. Here, we introduced a systematic platform, FRET-Seq, which integrates high-throughput FRET sorting and next-generation sequencing, to identify FRET biosensors with better performance from large-scale libraries directly in mammalian cells.

Chronic limb threat ischemia is associated with cardiovascular events, resulting in high amputation, morbidity and mortality rates. This study aims to accomplish a comprehensive summary of randomized controlled trials and single-center trials related to drug-coated balloons (DCBs) in the treatment of below-the-knee (BTK) artery disease, and to provide a recommendation for the application of DCBs in BTK artery disease.Five electronic databases were used to retrieve relevant articles on the safety and effectiveness of DCBs in the treatment of BTK artery disease. A random-effects model was applied to calculate the standard mean deviation, odds ratio (OR) and their 95% of confidence interval (CI).As of April 8, 2021, a total of 241 articles were retrieved, but only 13 articles were finally included for meta-analysis. The 12 mo follow-up study found that major adverse events , all-cause mortality, major amputation ,and target lesion revascularization had no statistically significant difference between the DCBs group and the control group (target lesion revascularization: OR = 0.68, 95% CI: 0.36, 1.31; all-cause mortality: OR = 1.30, 95% CI: 0.69, 2.46; major amputation: OR = 1.34, 95% CI: 0.64, 2.79; target lesion revascularization: OR = 0.72, 95% CI: 0.35, 1.45).The meta-analysis results of randomized controlled trials focusing on comparing DCBs and other treatments suggest that DCBs do not have significant advantages in the treatment of BTK artery disease when compare with percutaneous transluminal angioplasty (PTA), but better than control intervention except PTA in both safety and efficacy end points. However, the results of meta-analysis of single-arm trial reported DCBs in treating BTK artery lesions are significantly improved compared with the meta-analysis concentrating on PTA.

To investigate serum neutrophil gelatinase-associated lipocalin (sNGAL) and urine neutrophil gelatinase-associated lipocalin (uNGAL) as early predictors of contrast-associated acute kidney injury(contrast-induced nephropathy)following endovascular aortic repair for abdominal aortic aneurysm. Prospective cohort study. Subjects included 202 consecutive patients with abdominal aortic aneurysm diagnosed between February 2016 and October 2018. We divided the patients into 2 groups: contrast-induced nephropathy (CIN) (n = 26) and non-CIN (n = 176). We assessed correlations between sNGAL and uNGAL concentrations and standard renal markers at baseline, 6, 24, and 48 hours post-procedure. We constructed conventional receiver operating characteristic (ROC) curves and calculated the area under the curve to assess SCr, eGFR, sNGAL, and uNGAL performance. We derived biomarker cutoff levels from ROC analysis results to maximize sensitivity and specificity values. The CIN incidence within our cohort was 12.9%. sNGAL levels correlated significantly with SCr and eGFR at baseline, 6, and 24 hours post-contrast medium exposure. Similarly, uNGAL levels correlated with SCr and estimated glomerular filtration rate (eGFR) at baseline, 6, and 24 hours post-exposure. sNGAL and uNGAL were significantly elevated as early as 6 hours post-endotherapy in the CIN group; there were only minor changes in the non-CIN group. SCr was also significantly elevated in the CIN group, but not until 48 hours post-catheterization. Both sNGAL and uNGAL may be more accurate than SCr and eGFR as early biomarkers of CIN in patients with abdominal aortic aneurysm undergoing endovascular therapy.

Background Peptide probes can be applied for biomarker targeting to improve the diagnostic accuracy. Cluster of differentiation 44 (CD44) is up-regulated in gastric cancer (GC). Among all the variants of CD44, CD44v6 is reported the most promising biomarker for GC. The purpose of this study was generating and identification a peptide ligand specific to CD44v6. Methods A 12-mer phage peptide library was screened on CD44v overexpressed HEK-293 cells with an improved subtractive method. Five candidate sequences emerged. Candidate phages were selected using enzyme-linked immunosorbent assay and competitive inhibition assays. Then the sequence (designated ELT) was chosen for further study. Its binding affinity and specificity were verified on recombinant protein, GC cells, GC tissues and xenograft models based on BALB/c-nu/nu mice using dissociation constant calculation, immunofluorescence, immunohistochemistry and in vivo imaging separately. Results The dissociation constant of ELT with recombinant protein was 611.2 nM. ELT stained CD44v overexpressed HEK-293 but not the cell expressing wild-type CD44s. On GC cell lines, ELT co-stained with anti-CD44v6 antibody. ELT binding on tumor tissues significantly increased compared with that of paracancer tissues, also showed a linear positive correlation with CD44v6 expression. ELT specifically accumulated in tumor and eliminated in short time in vivo. Conclusions ELT can target GC in vitro and in vivo via CD44v6, indicating its potential to serve as a probe for GC targeting diagnosis and therapy.

The vital pathogenesis of varicose veins includes remodeling of the extracellular matrix and decreased vascular tone. Prostaglandin EThe collected venous specimens were analyzed using hematoxylin and eosin, Masson's trichrome, and immunohistochemical staining. Transforming growth factor (TGF)-β1, PGEThe expression of PGEPGE

Previous studies with various Src family kinase biosensors showed that the nuclear kinase activities are much suppressed compared to those in the cytosol, suggesting that these kinases are regulated differently in the nucleus and in the cytosol. In this study, using Fyn as an example, we first engineered a Fyn biosensor with a light-inducible nuclear localization signal to demonstrate that the Fyn kinase activity is significantly lower in the nucleus than in the cytosol. To understand how different equilibrium states between Fyn and the corresponding phosphatases are maintained in the cytosol and nucleus, we further engineered a Fyn kinase domain with light-inducible nuclear localization signal. The results revealed that the Fyn kinase can be actively transported into the nucleus upon light activation and upregulate the biosensor signals in the nucleus. Our results suggest that there is limited transport or diffusion of Fyn kinase between the cytosol and nucleus in the cells, which is important for the maintenance of different equilibrium states of Fyn in situ.

Advanced glycation end products (AGEs) induce vascular smooth muscle cells (VSMCs) contractile-synthetic phenotypic conversion which plays roles in aggravated atherosclerosis in diabetes. Matrine has been proved to suppress AGEs-induced phenotypic conversion which is governed by Notch pathway. Endoplasmic reticulum stress was associated with Notch pathway. Cultured human coronary smooth muscle cells (HCSMCs) were incubated with AGE-BSA at 0, 5 and 10 μmol/l. Specific siRNA was used to silence Protein kinase RNA-like ER kinase (PERK). Matrine at 0, 0.5 and 1.0 mmol/l were used to pre-treat the cells. Immunofluorescent staining of Smooth muscle myosin heavy chain 11 (MYH11) and smooth muscle α-actin 2 (ACTA2) were used to identify the contractile phenotype of HCSMCs. Protein phosphorylation and expression levels were evaluated by Western Blotting. AGE-BSA exposure facilitated the contractile-synthetic phenotypic conversion of HCSMCs in a concentration-dependent manner. AGE-BSA exposure increased expression levels of glucose-regulated protein 78 (GRP78), Delta-like 4 (Dll4), Notch intracellular domain (NICD1), Hes family basic helix-loop-helix (bHLH) transcriptional factor 1 (HES1), as well as the phosphorylation level of PERK. Specific perk-siRNA transfection dramatically lowered PERK phosphorylation and resulted in down-regulation of Dll4, NICD1 and HES1 in HCSMCs exposed to AGE-BSA. Pre-treatment of matrine suppressed AGE-BSA-induced phenotypic conversion of HCSMCs in a concentration-dependent manner. Moreover, matrine pre-treatment reduced expression level of GRP78, NICD1, HES1 and the phosphrylation level of PERK in AGE-BSA-exposed HCSMCs in a concentration-dependent manner. These results suggested that matrine suppressed AGE-BSA-induced HCSMCs phenotypic conversion via attenuating ER stress PERK signaling-dependent Dll4- Notch pathway activation.

Purpose To compare outcomes of patients who received simultaneous tributary endovenous laser ablation (EVLA) or foam sclerotherapy (FS) with EVLA of the great saphenous vein (GSV) trunk. Methods and Materials This study recruited 418 patients (542 legs) with diagnosed varicose veins. Patients in the EVLA/FS group (255 patients, 327 legs) received concomitant FS for the tributaries with truncal lasering. For the EVLA-alone group (163 patients, 215 legs), tributaries (8W) were ablated with EVLA in addition to the GSV trunk (14W). Complications, Aberdeen Varicose Vein Questionnaire (AVVQ), EuroQol Group 5-Dimension Self-Report Questionnaire (EQ-5D), numerical rating scale (NRS) scores, and condition of residual varicosities were assessed at 3 days, 4 weeks, and 6 months after procedure. All residual varicosities were identified and treated with a staged FS at 6 months. Results Except for ecchymosis, incidence of other complications was not significantly different between both groups at 6 months. Pain NRS scores of the EVLA/FS group were remarkably elevated at 4 weeks and then, at 6 months, declined to a level similar to the EVLA-alone group. The EVLA/FS group exhibited more significant improvement in both AVVQ and EQ-5D scales than the EVLA group at 6 months, while exhibiting poor improvement at 4 weeks. The EVLA/FS group had a significantly lower rate of residual varicosities than the EVLA group, thus reducing the need for the staged FS. Conclusions These results confirm the feasibility and safety of simultaneous tributary EVLA and FS. In addition, they indicate better early quality-of-life improvement and a reduced reoperation rate of simultaneously combined truncal EVLA and tributary FS.

Substantial data from preclinical studies have revealed the biphasic effects of statins on cardiovascular angiogenesis. Although some have reported the anti‐angiogenic potential of statins in malignant tumors, the underlying mechanism remains poorly understood. The aim of this study is to elucidate the mechanism by which simvastatin, a member of the statin family, inhibits tumor angiogenesis. Simvastatin significantly suppressed tumor cell‐conditioned medium‐induced angiogenic promotion in vitro, and resulted in dose‐dependent anti‐angiogenesis in vivo. Further genetic silencing of hypoxia‐inducible factor‐1α (HIF‐1α) reduced vascular endothelial growth factor and fibroblast growth factor‐2 expressions in 4T1 cells and correspondingly ameliorated HUVEC proliferation facilitated by tumor cell‐conditioned medium. Additionally, simvastatin induced angiogenic inhibition through a mechanism of post‐transcriptional downregulation of HIF‐1α by increasing the phosphorylation level of AMP kinase. These results were further validated by the fact that 5‐aminoimidazole‐4‐carboxamide ribonucleotide reduced HIF‐1α protein levels and ameliorated the angiogenic ability of endothelial cells in vitro and in vivo. Critically, inhibition of AMPK phosphorylation by compound C almost completely abrogated simvastatin‐induced anti‐angiogenesis, which was accompanied by the reduction of protein levels of HIF‐1α and its downstream pro‐angiogenic factors. These findings reveal the mechanism by which simvastatin induces tumor anti‐angiogenesis, and therefore identifies the target that explains the beneficial effects of statins on malignant tumors.

// Weiming Li 1, * , Huan Jia 2, * , Jichang Wang 1 , Hao Guan 1 , Yan Li 1 , Dan Zhang 3 , Yanan Tang 1 , Thomas D. Wang 4 , Shaoying Lu 1 1 Department of Vascular Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi Province, 710061, P.R.China 2 Department of General Surgery, The First Affiliated Hospital of Xi’an Medical University, Xi’an, Shaanxi Province, 710077, P.R.China 3 Department of Gastroenterology, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi Province, 710061, P.R.China 4 Division of Gastroenterology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI 48109, USA * Co-first authors, These authors contributed equally to this work Correspondence to: Shaoying Lu, email: robertlu@mail.xjtu.edu.cn Keywords: RP-1, CD44, gastric cancer, diagnosis, prognosis Received: September 22, 2016 Accepted: March 09, 2017 Published: March 16, 2017 ABSTRACT Early diagnosis and evaluation of prognosis are both crucial for preventing poor prognosis of patients with gastric cancer (GC), a leading cause of cancer-related deaths worldwide. Cluster of differentiation 44 (CD44), an indicator of cancer stem cells, can be specifically targeted by molecular probes and detected in tissues of GC in a large quantity. In current study we found that RP-1, a specific peptide binding to CD44 protein, exhibited the potentials of specific binding to CD44 high-expressing cancer cells both in vitro and in vivo , and the capacity of predicting prognosis of human GC in a microarray assay. Results showed that RP-1 was characterized by high affinity, sensitivity and specificity, and low toxicity, suggesting RP-1 could be an ideal bio-probe for accessory diagnosis of GC. Further immunohistochemical studies and statistical analysis of tissue microarray of human GC demonstrated similar sensitivity and specificity of RP-1 with the monoclonal anti-CD44 antibody in the diagnosis of GC, and even proved that positive RP-1 could be an independent risk factor. Therefore, this study suggests RP-1 has the potentials of binding to CD44 protein expressed on the membrane of GC cells, and demonstrates the feasibility and reliability of its further application in molecular diagnosis and prognostic prediction of GC.

A new biosensor was engineered to visualize Lck kinase preactivation and regulation in live T cells., Lck plays crucial roles in TCR signaling. We developed a new and sensitive FRET biosensor (ZapLck) to visualize Lck kinase activity with high spatiotemporal resolutions in live cells. ZapLck revealed that 62% of Lck signal was preactivated in T-cells. In Lck-deficient JCam T-cells, Lck preactivation was abolished, which can be restored to 51% by reconstitution with wild-type Lck (LckWT) but not a putatively inactive mutant LckY394F. LckWT also showed a stronger basal Lck-Lck interaction and a slower diffusion rate than LckY394F. Interestingly, aggregation of TCR receptors by antibodies in JCam cells led to a strong activation of reconstituted LckY394F similar to LckWT. Both activated LckY394F and LckWT diffused more slowly and displayed increased Lck-Lck interaction at a similar level. Therefore, these results suggest that a phosphorylatable Y394 is necessary for the basal-level interaction and preactivation of LckWT, while antibody-induced TCR aggregation can trigger the full activation of LckY394F.

Background Vascular maturity and functionality are closely associated with tumor progression and chemosensitivity. The antidiabetic agent metformin has shown its ability to inhibit tumor angiogenesis in metastatic breast cancer models. However, it remains unclear if or how metformin remodels the abnormal vasculature of metastatic breast cancer, while inhibiting angiogenesis. Methods Metastatic breast cancer models were constructed to compare microvessel density (MVD), vascular maturity and function, lung metastasis and chemosensitivity in metformin-treated or untreated mice. Protein array assay and transcriptome sequencing were performed for genetic screening. Lentiviral shRNA-PDGF-B transfection was used for observing the contribution of PDGF-B knockdown to metformin’s vascular effects. Results Metastatic breast cancers were characterized by an excessively angiogenic, immature and morphologically abnormal vasculature. Compared to control, metformin significantly reduced MVD, leakage and hypoxia, and increased vascular mural cells coverage and perfusion, namely, “vessel normalization”. Metformin at human blood concentrations had no direct effect on the migration and proliferation of cancer cells. Based on that, reduced lung metastasis of the primary tumor and improved chemosensitization by metformin were assumed to be mediated via metformin’s vascular effects. Further results of genetic screening and in vivo experiments showed that the downregulation of platelet-derived growth factor B (PDGF-B) greatly contributed to the metformin-induced vessel normalization. Conclusions These findings provide pre-clinical evidences for the vascular mechanism of metformin-induced metastasis inhibition and the chemosensitization of metastatic breast cancers. Electronic supplementary material The online version of this article (10.1186/s13046-019-1211-2) contains supplementary material, which is available to authorized users.

Fyn kinase plays crucial roles in hematology and T cell signaling; however, there are currently limited tools to visualize the dynamic Fyn activity in live cells. Here we developed and characterized a highly sensitive Fyn biosensor based on fluorescence resonance energy transfer (FRET) to monitor Fyn kinase activity in live cells. Our results show that Fyn kinase activity can be induced in both mouse embryonic fibroblasts (MEFs) and T cells by ligand engagement. Two different motifs were further introduced to target the biosensor at the cellular membrane microdomains in MEFs, revealing that the Fyn-tagged biosensor had 70% greater response to growth factor stimulation than the Lyn-tagged version. This suggests that the plasma membrane microdomains can be categorized into different functional subdomains. Further experiments show that while the membrane accessibility is necessary for Fyn activation, the localization of Fyn outside of its microdomains causes its hyperactivity, indicating that membrane microdomains provide a suppressive microenvironment for Fyn regulation in MEFs. Interestingly, a relatively high Fyn activity can be observed at perinuclear regions, further supporting the notion that the membrane microenvironment has a significant impact on the local molecular functions. Our work hence highlights a novel Fyn FRET biosensor for live cell imaging and its application in revealing an intricate submembrane regulation of Fyn in live MEFs.

CD44, especially the isoforms with variable exons (CD44v), is a promising biomarker for the detection of cancer. To develop a CD44v-specific probe, we screened a 7-mer phage peptide library against the CD44v3-v10 protein using an improved subtractive method. The consensus sequences with the highest frequency (designated CV-1) emerged after four rounds of panning. The binding affinity and specificity of the CV-1 phage and the synthesized peptide for the region of CD44 encoded by the variable exons were confirmed using enzyme-linked immunosorbent assay and competitive inhibition assays. Furthermore, the binding of the CV-1 probe to gastric cancer cells and tissues was validated using immunofluorescence and immunohistochemistry assays. CV-1 sensitively and specifically bound to CD44v on cancer cells and tissues. Thus, CV-1 has the potential to serve as a promising probe for cancer molecular imaging and target therapy.

This paper presents a observer-based fault estimation method for a class of singularly perturbed systems subjected to parameter uncertainties and time-delay in state and disturbance signal with finite energy. To solve the estimation problem involving actuator fault and sensor fault for the uncertain disturbed singularly perturbed systems with time-delay, the problem we studied is firstly transformed into a standard \begin{document}$ H_\infty $\end{document} control problem, in which the performance index \begin{document}$ \gamma $\end{document} represents the attenuation of finite energy disturbance. By adopting Lyapunov function with the \begin{document}$ \varepsilon $\end{document} -dependence, a sufficient condition can be derived which enables the designed observer to estimate different kinds of fault signals stably and accurately, and the result obtained by dealing with small perturbation parameter in this way is less conservative. A novel multi-objective optimization scheme is then proposed to optimal disturbance attenuation index \begin{document}$ \gamma $\end{document} and system stable upper bound \begin{document}$ \varepsilon^* $\end{document} , in this case, the designed observer can estimate the fault signals better in the presence of interference when the systems guarantee maximum stability bound. In the end, the validity and correctness of proposed scheme is verified by comparing the error between the estimated faults and the actual faults.

The dramatic reorganization of chromatin during mitosis is perhaps one of the most fundamental of all cell processes. It remains unclear how epigenetic histone modifications, despite their crucial roles in regulating chromatin architectures, are dynamically coordinated with chromatin reorganization in controlling this process. We have developed and characterized biosensors with high sensitivity and specificity based on fluorescence resonance energy transfer (FRET). These biosensors were incorporated into nucleosomes to visualize histone H3 Lys-9 trimethylation (H3K9me3) and histone H3 Ser-10 phosphorylation (H3S10p) simultaneously in the same live cell. We observed an anticorrelated coupling in time between H3K9me3 and H3S10p in a single live cell during mitosis. A transient increase of H3S10p during mitosis is accompanied by a decrease of H3K9me3 that recovers before the restoration of H3S10p upon mitotic exit. We further showed that H3S10p is causatively critical for the decrease of H3K9me3 and the consequent reduction of heterochromatin structure, leading to the subsequent global chromatin reorganization and nuclear envelope dissolution as a cell enters mitosis. These results suggest a tight coupling of H3S10p and H3K9me3 dynamics in the regulation of heterochromatin dissolution before a global chromatin reorganization during mitosis.

Background and study aims: To demonstrate the clinical use of a multimodal endoscope with a targeted fluorescently labeled peptide for quantitative detection of Barrett’s neoplasia. Patients and methods: We studied 50 patients with Barrett’s esophagus using a prototype multimodal endoscope with a fluorescently labeled peptide. Co-registered fluorescence and reflectance images were converted to ratios to correct for differences in distance and geometry over the image field of view. The ratio images were segmented using a unique threshold that maximized the variance between high and low intensities to localize regions of high grade dysplasia (HGD) and esophageal adenocarcinoma (EAC). Results: Early neoplasia (HGD and EAC) was identified with 94 % specificity and 96 % positive predictive value at a threshold of 1.49. The mean results for HGD and EAC were significantly greater than those for squamous/Barrett’s esophagus and low grade dysplasia by one-way analysis of variance (ANOVA). The receiver operator characteristic curve for detection of early neoplasia had an area under the curve of 0.884. No adverse events associated with the endoscope or peptide were found. Conclusion: A multimodal endoscope can quantify fluorescence images from targeted peptides to localize early Barrett’s neoplasia. (ClinicalTrials.gov number NCT01630798.)

Protein-based biosensors or activators have been engineered to visualize molecular signals or manipulate cellular functions. Here we integrate these two functionalities into one protein molecule, an integrated sensing and activating protein (iSNAP). A prototype that can detect tyrosine phosphorylation and immediately activate auto-inhibited Shp2 phosphatase, Shp2-iSNAP, is designed through modular assembly. When Shp2-iSNAP is fused to the SIRPα receptor which typically transduces anti-phagocytic signals from the ‘don’t eat me’ CD47 ligand through negative Shp1 signaling, the engineered macrophages not only allow visualization of SIRPα phosphorylation upon CD47 engagement but also rewire the CD47-SIRPα axis into the positive Shp2 signaling, which enhances phagocytosis of opsonized tumor cells. A second SIRPα Syk-iSNAP with redesigned sensor and activator modules can likewise rewire the CD47-SIRPα axis to the pro-phagocytic Syk kinase activation. Thus, our approach can be extended to execute a broad range of sensing and automated reprogramming actions for directed therapeutics., Protein-based biosensors have been engineered to interrogate cellular signaling and manipulate function. Here the authors demonstrate iSNAP, a tool to detect tyrosine phosphorylation and activate desired protein enzymes allowing the control of phagocytosis in macrophages.

For the constant linear system and a given quadratic performance index, study the optimal guaranteed cost analysis and control problems based on the linear matrix inequality (LMI) method. Through some lemmas, the conditions of the guaranteed cost state feedback control are converted into a problem of LMI solvability. By solving the LMI, the guaranteed cost controller parameters can be obtained. In turn, give an optimization algorithm with LMI constraints, to obtain optimal guaranteed cost control law. The results can be implemented by the Matlab, and the curve of control and state can be simulated by the Simulink. Finally, two numerical examples are used to verify the feasibility and the correctness of the result.

Increasing evidence confirms that aberrant miRNA expression contributes to breast cancer (BC) development and progression. However, the roles of different miRNAs in BC remain to be explored. In the present study, we demonstrated that miR-1297 expression was increased in BC tissues and cell lines. Our clinical analysis revealed that the upregulated miR-1297 expression was significantly correlated with poor prognostic features including advanced TNM stage and larger tumor size. Moreover, we found that miR-1297 was a novel independent prognostic marker for predicting 5-year survival of BC patients. The ectopic overexpression of miR-1297 promoted cell proliferation, cell cycle progression and inhibited apoptosis while miR-1297 knockdown reversed the effect. In addition, miR-1297 modulated PTEN by directly binding to its 3'-UTR, resulting in activation of AKT signaling. In clinical samples of BC, miR-1297 inversely correlated with PTEN, which was downregulated in BC. Alternation of PTEN expression or AKT inhibitor at least partially abolished the biological effects of miR-1297 on BC cells. In conclusion, our results indicated that miR-1297 functioned as an oncogene in regulating the proliferation, cell cycle and apoptosis of BC via targeting PTEN/PI3K/AKT signaling, and may represent a novel potential therapeutic target and prognostic marker for BC.