Left Ventricular Injection Research Articles

Bone-metastatic lung adenocarcinoma cells bearing CD74-ROS1 fusion interact with macrophages to promote their dissemination.

Approximately 40% of patients with lung adenocarcinoma (LUAD) often develop bone metastases during the course of their disease. However, scarcely any in vivo model of LUAD bone metastasis has been established, leading to a poor understanding of the mechanisms underlying LUAD bone metastasis. Here, we established a multiorgan metastasis model via the left ventricular injection of luciferase-labeled LUAD cells into nude mice and then screened out lung metastasis (LuM) and bone metastasis (BoM) cell subpopulations. BoM cells exhibited greater stemness and epithelial-mesenchymal transition (EMT) plasticity than LuM cells and initially colonized the bone and subsequently disseminated to distant organs after being reinjected into mice. Moreover, a CD74-ROS1 fusion mutation (C6; R34) was detected in BoM cells but not in LuM cells. Mechanistically, BoM cells bearing the CD74-ROS1 fusion highly secrete the C-C motif chemokine ligand 5 (CCL5) protein by activating STAT3 signaling, recruiting macrophages in tumor microenvironment and strongly inducing M2 polarization of macrophages. BoM cell-activated macrophages produce a high level of TGF-β1, thereby facilitating EMT and invasion of LUAD cells via TGF-β/SMAD2/3 signaling. Targeting the CD74-ROS1/CCL5 axis with Crizotinib (a ROS1 inhibitor) and Maraviroc (a CCL5 receptor inhibitor) in vivo strongly impeded bone metastasis and secondary metastasis of BoM cells. Our findings reveal the critical role of the CD74-ROS1/STAT3/CCL5 axis in the interaction between LUAD bone metastasis cells and macrophages for controlling LUAD cell dissemination, highlighting the significance of the bone microenvironment in LUAD bone metastasis and multiorgan secondary metastasis, and suggesting that targeting CD74-ROS1 and CCL5 is a promising therapeutic strategy for LUAD bone metastasis.

Outcomes in patients with aortic stenosis and severely reduced ejection fraction following surgical aortic valve replacement and transcatheter aortic valve replacement

BackgroundPatients with severe aortic stenosis (AS) and left ventricular (LV) dysfunction demonstrate improvement in left ventricular injection fraction (LVEF) after aortic valve replacement (AVR). The timing and magnitude of recovery in patients with very low LVEF (≤ 25%) in surgical or transcatheter AVR is not well studied.ObjectiveDetermine clinical outcomes following transcatheter aortic valve replacement (TAVR) and surgical aortic valve repair (SAVR) in the subset of patients with severely reduced EF ≤ 25%.MethodsSingle-center, retrospective study with primary endpoint of LVEF 1-week following either procedure. Secondary outcomes included 30-day mortality and delayed postprocedural LVEF. T-test was used to compare variables and linear regression was used to adjust differences among baseline variables.Results83 patients were enrolled (TAVR = 56 and SAVR = 27). TAVR patients were older at the time of procedure (TAVR 77.29 ± 8.69 vs. SAVR 65.41 ± 10.05, p < 0.001). One week post procedure, all patients had improved LVEF after both procedures (p < 0.001). There was no significant difference in LVEF between either group (TAVR 33.5 ± 11.77 vs. SAVR 35.3 ± 13.57, p = 0.60). Average LVEF continued to rise and increased by 101% at final follow-up (41.26 ± 13.70). 30-day mortality rates in SAVR and TAVR were similar (7.4% vs. 7.1%, p = 0.91).ConclusionPatients with severe AS and LVEF ≤ 25% have a significant recovery in post-procedural EF following AVR regardless of method. LVEF doubled at two years post-procedure. There was no significant difference in 30-day mortality or mean EF recovery between TAVR and SAVR.Trial registrationIndiana University institutional review board granted approval for above study numbered 15,322.

Pleckstrin homology and RhoGEF domain containing G4 (PLEKHG4) leads to the activation of RhoGTPases promoting the malignant phenotypes of thyroid cancer.

Thyroid cancer (TC) is one of the most common endocrine system cancers, and its incidence is elevating. There is an urgent need to develop a deeper understanding of TC pathogenesis and explore new therapeutic target for its treatment. This study aimed to investigate the effects of pleckstrin homology and RhoGEF domain containing G4 (PLEKHG4) on the progression of TC. Herein, 29 pairs of TC and adjacent tissues were used to assess the expression of PLEKHG4. A xenograft model of mouse was established by subcutaneously injected with TC cells. Lung metastasis model was established through left ventricular injection. The results revealed that PLEKHG4 was up-regulated in human TC tissues. PLEKHG4 level was correlated with clinicopathological parameters of TC patients. In vitro assays revealed that PLEKHG4 promoted TC cell proliferation, migration, invasion, and epithelial-mesenchymal transformation. Knockdown of PLEKHG4 led to the opposite effects, and the loss of PLEKHG4 enhanced the apoptosis ability and inhibited the stemness properties of TC cells. These findings were further confirmed by the in vivo growth and lung metastasis of TC tumor. Mechanistically, PLEKHG4 promoted the activation of RhoGTPases RhoA, Cdc42, and Rac1. The inhibitors of these RhoGTPases reversed the PLEKHG4-induced malignant phenotypes. Additionally, ubiquitin-conjugating enzyme E2O (UBE2O), a large E2 ubiquitin-conjugating enzyme acted as an ubiquitin enzyme of PLEKHG4, facilitated its ubiquitination and degradation. In conclusion, PLEKHG4, regulated by UBE2O, promoted the thyroid cancer progression via activating the RhoGTPases pathway. UBE2O/PLEKHG4/RhoGTPases axis is expected to be a novel a therapeutic target for TC treatment.

Efficacy and safety of intracoronary versus intravenous tirofiban in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention: A meta-analysis of randomized controlled trials

BackgroundEffective antiplatelet therapy is critical for patients with ST-segment elevation myocardial infarction (STEMI) and receiving primary percutaneous coronary interventions (PPCI). Intracoronary (IC) and intravenous (IV) administration of tirofiban are commonly used during the procedure of PPCI. However, which is the better administration route of tirofiban have not been fully evaluated. MethodsA comprehensive literature search of RCTs that comparing IC with IV tirofiban in STEMI patients undergoing PPCI was conducted, which were published as of May 7, 2022, in PubMed, Embase, Cochrane Library, Web of Science, Scopus and ClinicalTrials.gov. The primary efficacy endpoint was 30-day major adverse cardiovascular events (MACE) and the primary safety endpoint was in-hospital bleeding events. ResultsThis meta-analysis included 9 trials involving 1177 patients. IC tirofiban significantly reduced the incidence of 30-day MACE (RR 0.65, 95% CI: 0.44 to 0.95, P = 0.028) and improved the rate of the thrombolysis in myocardial infarction (TIMI) grade 3 flow in high-dose (25 μg/kg) group (RR = 1.13, 95% CI: 0.99–1.30, P = 0.001), in-hospital (WMD 2.03, 95% CI: 1.03 to 3.02, P < 0.001), and 6-month left ventricular injection fraction (LVEF) (WMD 6.01, 95% CI: 5.02 to 6.99, P < 0.001) compared with IV. There was no significant difference in the incidences of in-hospital bleeding events (RR 0.96, 95% CI: 0.67 to 1.38, P = 0.82) and thrombocytopenia (RR 0.63, 95% CI: 0.26 to 1.57, P = 0.32) between the two groups. ConclusionsIC tirofiban significantly improved the incidence of TIMI 3 in the high-dose group, in-hospital and 6-month LVEF, and reduced the 30-day MACE incidence without increasing the risk of bleeding compared with IV.

Congestive Heart Failure Patients’ Pulse Rate Progression and Time to Death at Debre Tabor Referral Hospital, Ethiopia

Background. Heart failure is a progressive condition marked by worsening symptoms such as shortness of breath, coughing, exhaustion and lethargy, fluid retention with swelling of the legs and abdomen, and a reduced ability to exercise. As a result, this study aims to use a joint model application to determine the joint risk factors of longitudinal change in pulse rate and time to death of congestive heart failure patients and their association admitted to a hospital. Methods. A retrospective study was undertaken on congestive heart failure patients admitted to the Debre Tabor Referral Hospital from January 2016 to December 2019. A statistical joint modeling strategy was employed to match the repeated biomarker pulse rate and a survival outcome at the same time. A total of 271 patients with congestive heart failure were chosen. Data were analyzed with R statistical software via joineRML. Results. According to the findings, the association between longitudinal changes in pulse rate and time to death in heart failure patients is statistically significant. Sex, residence, left ventricular injection fraction, New York Heart Association class, and diabetes mellitus were all found to be significant risk factors for congestive heart failure patients’ short survival time to death. Age, sex, residence, hypertension, left ventricular injection fraction, congestive heart failure, diabetes mellitus, tuberculosis, and etiology were all significant contributors in pulse rate progression. Conclusion. The computed association parameters revealed subject-specific values. The subject-specific linear time slope of PR measurement was positively related to the hazard rate of time to death of CHF patients in the study area. To reduce the risk level of CHF, health professionals, governmental organizations, and nongovernmental organizations must promote and allocate a suitable amount of budget for the treatment of CHF patients.

Abstract 6941: Cardiac Repair With Echocardiography-Guided Multiple Percutaneous Left Ventricular Intramyocardial Injection of Human Induced Pluripotent Stem Cell Derived Cardiomyocytes After Myocardial Infarction

Objective: To investigate the cardiac repair potency with echocardiography-guided multiple percutaneous left ventricular intramyocardial injection of human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) after myocardial infarction. Methods: The surgically induced myocardial infarcted mice were randomly divided into three groups (8 in each) and were injected with echocardiography-guided percutaneous left ventricular infarcted border zone of one shot hiPSC-CMs (single dose, 10ul of 3x10 5 cells), medium, or repeated delivery of hiPSC-CMs at post-MI week 1 and 2 (multiple dose). The sham group of animals underwent all surgical procedures necessary for MI induction except for the ligation step. 4 weeks after the MI, heart function was measured by the transthoracic echocardiography. The engraftment size was evaluated through the detection of human specific cardiac troponin T. Infarcted size and collagen volume were calculated by sirius-red and fast green staining. Angiogenesis was evaluated by the staining of isolectin B4. Cardiac remodeling was evaluated by the cardiomyocyte minimal fiber diameter in the infarcted border zone. Apoptosis was detected via tunel staining in cardiomyocyte from the infarcted border zone. Results: No death was detected with echocardiography-guided percutaneous left ventricular intramyocardial injection. The number of hiPSC-CMs was about 9-fold higher in multiple dose group at week 4 compaired to single dose group. The multiple dose transplantation was associated with significant improvement in left ventricular function, infarct size, angiogenesis, cardiac remodeling, and cardiomyocyte apoptosis. Conclusions: Echocardiography-guided multiple percutaneous left ventricular intramyocardial injection is a feasible, satisfactory, repeatable, relatively less invasive and effective delivery method for cell therapy and the delivery of hiPSC-CMs indicate a novel therapy for myocardial infarction.

Cardiac Repair With Echocardiography-Guided Multiple Percutaneous Left Ventricular Intramyocardial Injection of hiPSC-CMs After Myocardial Infarction.

Objective: We investigated the potency of cardiac repair based on echocardiography-guided multiple percutaneous left ventricular intramyocardial injection of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) after myocardial infarction (MI).Methods: Mice with surgically induced MI were randomly divided into three groups (n = 8 in each group) and subjected to echocardiography-guided percutaneous left ventricular infarcted border injection of hiPSC-CMs (single dose; 10 μl 3 × 105 cells) or repeated injections of hiPSC-CMs at post-MI weeks 1 and 2 (multiple doses). The sham group of animals underwent all surgical procedures necessary for MI induction except for ligation. Then 4 weeks after MI, heart function was measured with transthoracic echocardiography. Engraftment was evaluated through the detection of human-specific cardiac troponin T. Infarct size and collagen volume were calculated with Sirius Red/Fast Green staining. Angiogenesis was evaluated with isolectin B4 staining. Cardiac remodeling was evaluated from the cardiomyocyte minimal fiber diameter in the infarcted border zone. Apoptosis was detected via TdT-mediated dUTP Nick-End Labeling (TUNEL) staining in cardiomyocytes from the infarcted border zone.Results: No mice died after echocardiography-guided percutaneous left ventricular intramyocardial injection. hiPSC-CMs were about nine-fold higher in the multiple-dose group at week 4 compared to the single-dose group. Multiple-dose transplantation was associated with significant improvement in left ventricular function, infarct size, angiogenesis, cardiac remodeling, and cardiomyocyte apoptosis.Conclusion: Echocardiography-guided multiple percutaneous left ventricular intramyocardial injection is a feasible, satisfactory, repeatable, relatively less invasive, and effective method of delivering cell therapy. The delivery of hiPSC-CMs indicates a novel therapy for MI.

Prospects of heart failure pharmacotherapy: the latest news about omecamtiv mecarbil

Over the past decades, an active scientific research has been continuing aimed on the search for medications that can increase myocardial contractility and improve the course of heart failure (HF). omecamtiv mecarbil, a drug from the group of cardiac myosin activators, heads the list of applicants for clinical use. By today, evidences have been collected for the ability of omecamtiv mecarbil to bind exclusively to the heads of cardiac myosin molecules without significantly affecting smooth or skeletal muscle myosin. omecamtiv mecarbil stabilizes pre‑step myosin conformation, enabling the greater number of its heads to participate in the working phase of systole.The article presents the results of several randomized clinical trials that studied the efficacy and safety of omecamtiv mecarbil in heart failure: ATOMIC‑AHF, COSMIC‑HF and GALACTIC‑HF. ATOMIC‑AHF showed a tendency to reduce the risk of developing supraventricular and ventricular arrhythmias in heart failure. COSMIC‑HF has proven the ability of omecamtiv mecarbil to improve the quality of life of patients with heart failure. GALACTIC‑HF may be a turning point in the medical treatment of heart failure. For the first time, clinical evidence of the ability of the selective cardiac myosin activator omecamtiv mecarbil to improve myocardial contractile function, reduce the severity of symptoms of heart failure and reduce the risk of cardiovascular death in patients with the reduced left ventricular injection friction was obtained. It is too early to draw final conclusions about the advisability of omecamtiv mecarbil administration for heart failure. The findings of new comparative randomized clinical trials, systemic reviews and meta‑analyses may possibly alter the standards of treatment of this pathology.

Echocardiography-guided percutaneous left ventricular intracavitary injection as a cell delivery approach in infarcted mice.

In the field of cell therapy for heart disease, a new paradigm of repeated dosing of cells has recently emerged. However, the lack of a repeatable cell delivery method in preclinical studies in rodents is a major obstacle to investigating this paradigm. We have established and standardized a method of echocardiography-guided percutaneous left ventricular intracavitary injection (echo-guided LV injection) as a cell delivery approach in infarcted mice. Here, we describe the method in detail and address several important issues regarding it. First, by integrating anatomical and echocardiographic considerations, we have established strategies to determine a safe anatomical window for injection in infarcted mice. Second, we summarize our experience with this method (734 injections). The overall survival rate was 91.4%. Third, we examined the efficacy of this cell delivery approach. Compared with vehicle treatment, cardiac mesenchymal cells (CMCs) delivered via this method improved cardiac function assessed both echocardiographically and hemodynamically. Furthermore, repeated injections of CMCs via this method yielded greater cardiac function improvement than single-dose administration. Echo-guided LV injection is a feasible, reproducible, relatively less invasive and effective delivery method for cell therapy in murine models of heart disease. It is an important approach that could move the field of cell therapy forward, especially with regard to repeated cell administrations.

Catheter-based endomyocardial injection with real-time magnetic resonance imaging.

We tested the feasibility of targeted left ventricular (LV) mural injection using real-time MRI (rtMRI). A 1.5T MRI scanner was customized with a fast reconstruction engine, transfemoral guiding catheter-receiver coil (GCC), MRI-compatible needle, and tableside consoles. Commercial real-time imaging software was customized to facilitate catheter navigation and visualization of injections at 4 completely refreshed frames per second. The aorta was traversed and the left ventricular cavity was entered under direct rtMRI guidance. Pigs underwent multiple injections with dilute gadolinium-DTPA. All myocardial segments were readily accessed. The active GCC and the passive Stiletto needle injector were readily visualized. More than 50 endomyocardial injections were performed with the aid of rtMRI; 81% were successful with this first-generation prototype. Percutaneous endomyocardial drug delivery is feasible with the aid of rtMRI, which permits precise 3-dimensional localization of injection within the LV wall.

Canine prostatic cancer cell line (LuMa) with osteoblastic bone metastasis.

Osteoblastic bone metastasis represents the most common complication in men with prostate cancer (PCa). During progression and bone metastasis, PCa cells acquire properties similar to bone cells in a phenomenon called osteomimicry, which promotes their ability to metastasize, proliferate, and survive in the bone microenvironment. The mechanism of osteomimicry resulting in osteoblastic bone metastasis is unclear. We developed and characterized a novel canine prostatic cancer cell line (LuMa) that will be useful to investigate the relationship between osteoblastic bone metastasis and osteomimicry in PCa. The LuMa cell line was established from a primary prostate carcinoma of a 13-year old mixed breed castrated male dog. Cell proliferation and gene expression of LuMa were measured and compared to three other canine prostatic cancer cell lines (Probasco, Ace-1, and Leo) in vitro. The effect of LuMa cells on calvaria and murine preosteoblastic (MC3T3-E1) cells was measured by quantitative reverse-transcription polymerase chain reaction and alkaline phosphatase assay. LuMa cells were transduced with luciferase for monitoring in vivo tumor growth and metastasis using different inoculation routes (subcutaneous, intratibial [IT], and intracardiac [IC]). Xenograft tumors and metastases were evaluated using radiography and histopathology. After left ventricular injection, LuMa cells metastasized to bone, brain, and adrenal glands. IT injections induced tumors with intramedullary new bone formation. LuMa cells had the highest messenger RNA levels of osteomimicry genes (RUNX2, RANKL, and Osteopontin [OPN]), CD44, E-cadherin, and MYOF compared to Ace-1, Probasco, and Leo cells. LuMa cells induced growth in calvaria defects and modulated gene expression in MC3T3-E1 cells. LuMa is a novel canine PCa cell line with osteomimicry and stemness properties. LuMa cells induced osteoblastic bone formation in vitro and in vivo. LuMa PCa cells will serve as an excellent model for studying the mechanisms of osteomimicry and osteoblastic bone and brain metastasis in prostate cancer.

Shenmai Injection Improves Energy Metabolism in Patients With Heart Failure: A Randomized Controlled Trial.

BackgroundIn recent years, the application of Shenmai (SM) injection, a traditional Chinese medicine (TCM), to treat heart failure (HF) has been gradually accepted in China. However, whether SM improves energy metabolism in patients with HF has not been determined due to the lack of high-quality studies. We aimed to investigate the influence of SM on energy metabolism in patients with HF.MethodsThis single-blind, controlled study randomly assigned 120 eligible patients equally into three groups receiving SM, trimetazidine (TMZ), or control in addition to standard medical treatment for HF for 7 days. The primary endpoints were changes in free fatty acids (FFAs), glucose, lactic acid (LA), pyroracemic acid (pyruvate, PA) and branched chain amino acids (BCAAs) in serum. The secondary outcomes included the New York Heart Association (NYHA) functional classification, TCM syndrome score (TCM-s), left ventricular injection fraction (LVEF), left ventricular internal diastolic diameter (LVIDd), left ventricular internal dimension systole (LVIDs), and B-type natriuretic peptide (BNP).ResultsAfter treatment for 1 week, the NYHA functional classification, TCM-s, and BNP level gradually decreased in the patients in all three groups, but these metrics were significantly increased in the patients in the SM group compared with those in the patients in the TMZ and control groups (P < 0.05). Moreover, energy metabolism was improved in the NYHA III–IV patients in the SM group compared with those in the patients in the TMZ and control groups as evidenced by changes in the serum levels of FFA, LA, PA, and BCAA.ConclusionsIntegrative treatment with SM in addition to standard medical treatment for HF was associated with improved cardiac function compared to standard medical treatment alone. The benefit of SM in HF may be related to an improvement in energy metabolism, which seems to be more remarkable than that following treatment with TMZ.

PD64-08 LYSOSOMAL PROTEIN TRANSMEMBRANE 5 MEDIATES LUNG-SPECIFIC METASTASIS OF RENAL CANCER BY REGULATING BMP/SMAD1 PATHWAY

You have accessJournal of UrologyKidney Cancer: Basic Research & Pathophysiology III (PD64)1 Apr 2020PD64-08 LYSOSOMAL PROTEIN TRANSMEMBRANE 5 MEDIATES LUNG-SPECIFIC METASTASIS OF RENAL CANCER BY REGULATING BMP/SMAD1 PATHWAY Bo Jiang*, Wei Chen, Xiaozhi Zhao, and Hongqian Guo Bo Jiang*Bo Jiang* More articles by this author , Wei ChenWei Chen More articles by this author , Xiaozhi ZhaoXiaozhi Zhao More articles by this author , and Hongqian GuoHongqian Guo More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000000981.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Despite progression in cancer control and survival, metastases are still diagnosed in a notable proportion of renal cancer (RCC) patients with a significant tendency to lung. Lung metastasis seriously affects the prognosis of patients and the current clinical drugs fail to achieve satisfactory therapeutic effects. It is urgent to develop new drugs based on the molecular theory of lung metastasis of RCC for better personalized treatment. However, the research on the mechanism of lung-specific metastasis of RCC is still blank. METHODS: Left ventricular injection of luci-labeled murine RCC cells (Renca-Luci) was used to establish the multiple organ metastasis model of RCC, metastases were measured by in vivo imaging system, then metastatic tumor cells in lung and other organs were primarily cultured. After verification, metastatic cells from lung (LuM), brain (BrM) and bone (BoM) along with untreated parental Renca cells were sent for high-throughput RNA-seq analysis. Sphere formation assay and subcutaneous tumor formation assay were conducted to test the stemness of RCC cells. In addition, we further evaluated the effect of lysosomal inhibitor (chloroquine) on the regulation of the BMP/SMAD1 pathway by LAPTM5, and attempted to explore its application prospect of anti-pulmonary metastasis. RESULTS: LuM, BrM, BoM and parental Renca-Luci cells were re-injected into left ventricular of mice, LuM cells showed greater ability to invade the lungs than other cells. LAPTM5 revealed significantly higher mRNA level according to the RNA-seq data and further validated by western-blotting assay at protein level. Overexpression of LAPTM5 in Renca and 786-O cells facilitated the formation of pulmonary metastases in mice, conversely, down-regulation of LAPTM5 in Renca cells significantly reduced lung metastatic lesions. Meanwhile, the ability to invade the brain and bone of Renca-Luci cells was not significantly affected which suggested that LAPTM5 mediates lung-specific metastasis of RCC. BMP/SMAD1 signal suppressed cancer stem cell behavior and was responsible for tumor cell dormancy in the lungs, we provided evidence that LAPTM5 inhibited phosphorylation of smad1 of RCC cells after stimulated with recombinant BMP4 and thereby enhancing the self-renewal capability of RCC cells, the inhibitory effect disappeared after chloroquine treatment. CONCLUSIONS: Our results unraveled that LAPTM5 mediates lung-specific metastasis of RCC by inhibiting BMP/SMAD1 pathway and represents therapeutic targets for RCC. Source of Funding: This work was supported by grants from the National Natural Science Foundation of China (81502203, 81772710), the National Natural Science Foundation of Jiangsu Province (BK20150097), the Project of Invigorating Health Care through Science, Technology and Education Jiangsu Provincial Key Medical Discipline (ZDXKB201601 4), the “Summit of the Six Top Talents” Program of Jiangsu Province (SWYY-084), Postdoctoral Scientific Research Project of China (2017M621729) and the Postdoctoral Research Foundation of Jiangsu Province (1701021B), Nanjing Medical Science and technique Development Foundation (QRX17139). © 2020 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 203Issue Supplement 4April 2020Page: e1303-e1303 Advertisement Copyright & Permissions© 2020 by American Urological Association Education and Research, Inc.MetricsAuthor Information Bo Jiang* More articles by this author Wei Chen More articles by this author Xiaozhi Zhao More articles by this author Hongqian Guo More articles by this author Expand All Advertisement PDF downloadLoading ...

Interaction of tumor cells and astrocytes promotes breast cancer brain metastases through TGF-\u03b22/ANGPTL4 axes

Metastatic outcomes depend on the interactions of metastatic cells with a specific organ microenvironment. Our previous studies have shown that triple-negative breast cancer (TNBC) MDA-MB-231 cells passaged in astrocyte-conditioned medium (ACM) show proclivity to form brain metastases, but the underlying mechanism is unknown. The combination of microarray analysis, qPCR, and ELISA assay were carried out to demonstrate the ACM-induced expression of angiopoietin-like 4 (ANGPTL4) in TNBC cells. A stable ANGPTL4-knockdown MDA-MB-231 cell line was generated by ANGPTL4 short-hairpin RNA (shRNA) and inoculated into mice via left ventricular injection to evaluate the role of ANGPTL4 in brain metastasis formation. The approaches of siRNA, neutralizing antibodies, inhibitors, and immunoprecipitation were used to demonstrate the involved signaling molecules. We first found that ACM-conditioned TNBC cells upregulated the expression of ANGPTL4, a secreted glycoprotein whose effect on tumor progression is known to be tumor microenvironment- and tumor-type dependent. Knockdown of ANGPTL4 in TNBC MDA-MB-231 cells with shRNA decreased ACM-induced tumor cell metastatic growth in the brain and attributed to survival in a mouse model. Furthermore, we identified that astrocytes produced transforming growth factor-beta 2 (TGF-β2), which in part is responsible for upregulation of ANGPTL4 expression in TNBC through induction of SMAD signaling. Moreover, we identified that tumor cells communicate with astrocytes, where tumor cell-derived interleukin-1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) increased the expression of TGF-β2 in astrocytes. Collectively, these findings indicate that the invading TNBC cells interact with astrocytes in the brain microenvironment that facilitates brain metastases of TNBC cells through a TGF-β2/ANGPTL4 axis. This provides groundwork to target ANGPTL4 as a treatment for breast cancer brain metastases.

Direct implantations of erythropoietin and autologous EPCs in critical limb ischemia (CLI) area restored CLI area blood flow and rescued remote AMI-induced LV dysfunction

BackgroundThis study tested the hypothesis that intramuscular injections of erythropoietin (EPO) and endothelial progenitor cells (EPC) to critical limb ischemia (CLI; primary treatment site) could also improve heart function in rat after acute myocardial infarction (AMI; remote ischemic organ). MethodAdult-male SD rats (n = 40) were equally categorized into group 1 (sham-operated control), group 2 (CLI-AMI), group 3 [CLI-AMI + EPO (10 mg/kg)], group 4 [CLI-AMI + EPCs (1.2 × 106)] and group 5 (CLI-AMI + EPCs + EPO). ResultsBy day 21 (end of study period), 2-D echo and Laser doppler showed that left-ventricular injection fraction (LVEF) and the ratio of ischemic to normal blood flow were highest in group 1, lowest in group 2, significantly higher in group 5 than in groups 3 and 4, but not different in the latter two groups (all p < 0.0001). Flow cytometry and ELISA demonstrated that circulating angiogenesis factors were significantly progressively increased from groups 1 to 5 (all p < 0.001). The number of small vessels and protein (CD31/eNOS)/cellular (vWF) expressions reflecting integrity of endothelium exhibited an identical pattern to LVEF whereas protein (VEGF/SDF-1α)/cellular (VEGF) expressions were significantly progressively increased from groups 1 to 5 in quadriceps and heart tissues (all p < 0.0001). Protein expressions of apoptotic (Bax/caspase-3/PARP)/inflammatory (MMP-9) and microscopic findings of ischemic/fibrotic/collagen-deposition areas and DNA-damage marker (γ-H2AX+) were lowest in group 1 and significantly progressively decreased from groups 2 to 5 in quadriceps and heart tissues (all p < 0.0001). ConclusionsDirect injection of EPO-EPC into CLI effectively restored blood flow in the CLI area and also preserved remote heart function.

TLR9-HIF-1α-VEGF Axis Is Essential for HMGB1-Mediate Post-Myocardial Infarction Tissue Repair

Background: Toll-like receptor 9 (TLR9) as an essential part of the innate immune system plays a vital role in regulating cardiomyocyte survival and wound healing. During hypoxia, High Mobility Group Box 1 (HMGB1) is rapidly released extracellularly and translocates from the nucleus to bind with cytoplasmic TLR9. However, the mechanism by which TLR9 interacts with HMGB1 and regulates myocardial damage remains unclear. Our current study investigated the effects of TLR9 and HMGB1 on experimental MI. Methods: Experimental MI was induced by left anterior descending (LAD) ligation in wild type (WT) or TLR9 knockout (TLR9KO)mice, to delineate the functional effects of TLR9 on cardiac healing, apoptosis, angiogenesis. Left ventricular injection of recombination human HMGB1(rhHMGB1)was performed to explore the mechanism of TLR9 and HMGB1 in MI. Findings: The survival rate of TLR9KO mice with a higher rate of cardiac rupture was significantly lower than that in WT mice after 28-days postoperation. The effect of TLR9 knockout on insufficient wound healing in experimental MI is caused by a diminished number of myofibroblasts and defective matrix synthetic capability. Moreover, the increased myocardial apoptotic cells and decreased angiogenic capacity were found in TLR9 knockout mice after MI. The results showed contrary in rhHMGB1 (Recombinant Human High Mobility Group Box 1) treated WT mice and similarity after applying rhHMGB1 in TLR9KO mice. Interpretation: Our study demonstrates that TLR9 is essential for the repair of infarcted myocardium and interaction of HMGB1 and TLR9 is involved in the survival and wound healing of myocardial cells after myocardial infarction. Funding Statement: This work was supported by grants from the National Natural Science Foundation of China (No: 81470402, 81800216, 81700218, 81770399 and 81700254), the Key Project of the National Natural Science Foundation (No. 81530012) and the Fundamental Research Funds for the Central Universities (No. 2042017kf0085, 2042018kf1032 and 2042015kf0073). Declaration of Interests: The authors declare: None. Ethics Approval Statement: All human heart samples are dedicated for research purposes only, approved by the Renmin Hospital of Wuhan University Review Board, according to the Helsinki Declaration. All animal care and experimental procedures were approved by the Animal Care and Use Committee of Renmin Hospital of Wuhan University (approval no. 2016005) in accordance with the guidelines for the Care and Use of Laboratory Animals published by the United States National Institutes of Health (NIH).

GAP43, a novel metastasis promoter in non-small cell lung cancer

BackgroundBrain metastasis is an extremely serious sequela with a dismal prognosis in non-small cell lung cancer (NSCLC). The present study aimed to identify novel biomarkers and potential therapeutic targets for brain metastases of NSCLC.MethodsWe performed high-throughput Luminex assays to profile the transcriptional levels of 36 genes in 70 operable NSCLC patients, among whom 37 developed brain metastases as the first relapse within 3 years after surgery. The Cox proportional hazards regression model was used to evaluate the association between genes and brain metastases. Wound healing assay and transwell assay was carried out to estimate the function of target gene in vitro. And left ventricular injection on nude mice was used to evaluate the effect of target gene in vivo.ResultsGrowth-associated protein 43 (GAP43) was found to be related to brain metastasis. Multivariate Cox regression analysis showed that NSCLC patients with elevated GAP43 had a 3.29-fold increase in the risk for brain metastasis compared with those with low levels (95% confidence interval: 1.55–7.00; P = 0.002). Kaplan–Meier survival curves revealed that GAP43 was also associated with overall survival. Analysis of a cohort of 1926 NSCLC patients showed similar results: patients with high levels of GAP43 had worse progression-free and overall survival rates. Furthermore, in vitro experiments showed that GAP43 facilitated cell migration. Animal studies demonstrated that GAP43-silenced NSCLC cells were less likely to metastasize to the brain and bone than control cells. Immunofluorescence and F-actin/G-actin in vivo assays indicated that GAP43 knockdown triggered depolymerization of the F-actin cytoskeleton. Rho GTPase activation assays showed that Rac1 was deactivated after GAP43 was silenced.ConclusionsOur findings suggest that GAP43 is an independent predictor of NSCLC brain metastasis and that it may facilitate metastasis by regulating the Rac1/F-actin pathway.

Maximum Arterial Contrast Concentrations With Computed Tomography and Left Ventriculography: Implications for Contrast Nephrotoxicity Risk

Contrast nephropathy occurs more frequently after cardiac angiography, which usually includes left ventriculography via direct left ventricular injection, than after contrast-enhanced computed tomography (CT), despite the usually higher intravenous contrast dose used for CT. To determine whether maximum renal arterial contrast concentration is higher after left ventriculography, we assessed this parameter for both procedures. Contrast concentration in abdominal aortic blood during contrast-enhanced CT was measured by performing CT densitometry of aortic blood before contrast, and in the arterial phase, in 100 adults undergoing abdominal CT. Densities were converted to contrast concentrations by scanning water phantoms containing 20 graded concentrations of contrast and comparing their densities to patient data. Because it was impossible to perform CT densitometry during cardiac angiography, aortic contrast concentrations were calculated from standard contrast doses and injection rates with the range of clinically encountered cardiac output rates, assuming ultimate steady state for blood/contrast mixing and normal data distribution. Maximum aortic (and hence renal arterial) concentrations were significantly higher (range, 6.68%-15.90%) after ventriculography than after CT (1.22%-5.80%). Because ventricular injection times are much shorter than published initial-appearance-to-maximum-concentration times after intravenous administration, the rate of change of contrast concentration is also higher after ventriculography than after CT. Higher maximum renal arterial contrast concentration may be responsible for the greater risk of nephropathy after cardiac angiography than after doses for CT. The faster rate of change of renal arterial contrast concentration after ventriculography may also increase the likelihood of renal toxicity. Maximum renal arterial contrast concentration, and/or the rapidity of change of this parameter, may be partly responsible for the risk of nephropathy. Controlling these factors might permit reduction of nephropathy risk; they also suggest avenues of research into the pathophysiology of contrast nephropathy.

Loss of Endothelial CXCR7 Impairs Vascular Homeostasis and Cardiac Remodeling After Myocardial Infarction

Background: Genome-wide association studies identified the association of the CXCL12 genetic locus (which encodes the chemokine CXCL12, also known as stromal cell–derived factor 1) with coronary artery disease and myocardial infarction (MI). Unlike CXCR4, the classic receptor for CXCL12, the function of CXCR7 (the most recently identified receptor) in vascular responses to injury and in MI remains unclear. Methods: Tissue expression of CXCR7 was examined in arteries from mice and humans. Mice that harbored floxed CXCR7 and Cdh5 -promoter driven CreERT2 were treated with tamoxifen to induce endothelium-restricted deletion of CXCR7. The resulting conditional knockout mice and littermate controls were studied for arterial response to angioplasty wire injury and cardiac response to coronary artery ligation. The role of CXCR7 in endothelial cell proliferation and angiogenesis was determined in vitro with cells from mice and humans. The effects of adenoviral delivery of CXCR7 gene and pharmacological activation of CXCR7 were evaluated in mice subjected to MI. Results: Injured arteries from both humans and mice exhibited endothelial CXCR7 expression. Conditional endothelial CXCR7 deletion promoted neointimal formation without altering plasma lipid levels after endothelial injury and exacerbated heart functional impairment after MI, with increased both mortality and infarct sizes. Mechanistically, the exacerbated responses in vascular and cardiac remodeling are attributable to the key role of CXCR7 in promoting endothelial proliferation and angiogenesis. Impressively, the impaired post-MI cardiac remodeling occurred with elevated levels of CXCL12, which was previously thought to mediate cardiac protection by exclusively engaging its cognate receptor, CXCR4. In addition, both CXCR7 gene delivery via left ventricular injection and treatment with a CXCR7 agonist offered cardiac protection after MI. Conclusions: CXCR7 represents a novel regulator of vascular homeostasis that functions in the endothelial compartment with sufficient capacity to affect cardiac function and remodeling after MI. Activation of CXCR7 may have therapeutic potential for clinical restenosis after percutaneous coronary intervention and for heart remodeling after MI.

Procalcitonin Impairs Endothelial Cell Function and Viability.

Procalcitonin is used as a diagnostic tool for the identification and risk stratification of septic patients. Procalcitonin plasma concentrations tightly correlate with the severity of the ongoing inflammatory reaction and can rise up to 10,000-fold. Impairment of endothelial cell function plays an important role in the pathogenesis of hypotension and disturbed organ perfusion during sepsis. We investigated the possible effects of procalcitonin itself on endothelial cell function and viability. Human endothelial cells were exposed to 0.01 to 100 ng/mL procalcitonin and investigated for endothelial permeability using transwells, migration in a scratch wound assay and new capillary formation on extracellular matrix in vitro. Tumor necrosis factor-α and vascular endothelial growth factor served as positive controls. Procalcitonin's impact on the response of endothelial cells toward ischemia was investigated in vivo in the murine model of unilateral femoral artery ligation. Procalcitonin-exposed endothelial cells were subjected to immunoblot for the investigation of vascular endothelial-cadherin expression and angiogenic signaling pathways. Flow cytometry was used for the detection of inflammatory activation and viability, and genomic analysis was performed. Data are presented as difference in means and 95% confidence intervals; statistical analyses were performed using analysis of variance/Bonferroni, and P values are reported as adjusted for multiple comparisons (Padjust). Tumor necrosis factor-α and 0.1 ng/mL procalcitonin induced endothelial barrier disruption after incubation of endothelial monolayers for 6 hours (-2.53 [-4.16 to -0.89], P = .0008 and -2.09 [-3.73 to -0.45], Padjust = .0064 compared with vehicle-treated control, respectively). Procalcitonin beginning at concentrations of 0.02 ng/mL reduced endothelial cell migration (0.26 [0.06 to 0.47], Padjust = .0069) and new capillary formation in vitro (0.47 [0.28 to 0.66], Padjust < .0001) contrasting the proangiogenic action of vascular endothelial growth factor. Left ventricular injection of procalcitonin in mice on postoperative day 1, 3, and 5 after induction of ischemia impaired new capillary formation and recovery of hindlimb perfusion in vivo (number of capillaries/mm in the ischemic leg of vehicle-treated versus procalcitonin-treated mice, 852.6 [383.4-1322], Padjust = .0002). Twenty-four-hour incubation with procalcitonin reduced the expression of vascular endothelial-cadherin at 100 ng/mL (0.39 [0.06-0.71], Padjust = .0167) and induced endothelial cell death (apoptosis, -5.4 [-10.67 to -0.13], Padjust = .0431). No alteration in the expression of intercellular adhesion molecule-1, vascular cell adhesion molecule-1 or extracellular signal-regulated kinase 1/2, and AKT signaling pathways was observed. Genomic analysis revealed regulation of a variety of genes involved in inflammation, angiogenesis, and cell growth. This study found that procalcitonin itself impaired several aspects of endothelial cell function. Procalcitonin-induced loss of endothelial barrier function may contribute to capillary leakage and therapy-refractory hypotension during sepsis. Anti-angiogenic properties of procalcitonin at low concentrations could also identify procalcitonin as a mediator of vascular disease associated with the metabolic syndrome. Future studies are needed to further test procalcitonin as a potential therapeutic target for preserving vascular dysfunction during acute and chronic inflammatory disorders.