bluuebunny/crossref_metadata_2025 huggingface dataset:
Retrograde shear rate in formerly preeclamptic and healthy women before and after exercise training: relationship with endothelial function
Authors: Scholten Ralph R. , Spaanderman Marc E. A. , Green Daniel J. , Hopman Maria T. E. , Thijssen Dick H. J.
Published: June 2014

Blood flow patterns in conduit arteries characterized by high levels of retrograde shear stress can be detrimental for vascular health. In this study we examined whether retrograde shear rate and endothelial function are related in healthy and formerly preeclamptic (PE) women and whether this relationship is altered by exercise training. Formerly PE women (32 ± 4 yr, n = 20) and controls (32 ± 4 yr, n = 20), all 6–12 mo postpartum, performed 12-wk aerobic exercise training. We measured brachial artery shear rate (SR) and endothelial function by flow-mediated dilation (FMD, echo-Doppler). We additionally performed power spectral analysis of heart rate variability and calculated low-frequency/high-frequency (LF/HF) ratio. Antegrade SR was not different between groups, while retrograde SR was significantly higher and FMD% lower in PE women compared with controls (both P < 0.05). Retrograde shear correlated strongly with FMD% in PE women and controls ( P < 0.05). LF/HF ratio inversely correlated with brachial artery retrograde SR and FMD% (both P < 0.05) in PE women and controls. Exercise training reduced retrograde shear, improved FMD%, and reduced LF/HF ratios similarly in both groups (all P < 0.05). Training-induced changes in retrograde SR correlated with changes in FMD% and LF/HF ratio. A higher brachial artery retrograde SR relates to lower brachial artery endothelial function, in both controls and formerly PE women. Exercise training improves retrograde SR, while the magnitude of this change correlated strongly with improvements in FMD and reductions in LF/HF ratio. Therefore, the impact of PE and exercise training on endothelial health may, at least partly, be related to retrograde shear rate.
cIMP synthesized by sGC as a mediator of hypoxic contraction of coronary arteries
Authors: Chen Zhengju , Zhang Xu , Ying Lei , Dou Dou , Li Yanhui , Bai Yun , Liu Juan , Liu Limei , Feng Han , Yu Xiaoxing , Leung Susan Wai-Sum , Vanhoutte Paul M. , Gao Yuansheng
Published: June 2014

cGMP is considered the only mediator synthesized by soluble guanylyl cyclase (sGC) in response to nitric oxide (NO). However, purified sGC can synthesize several other cyclic nucleotides, including inosine 3′,5′-cyclic monophosphate (cIMP). The present study was designed to determine the role of cIMP in hypoxic contractions of isolated porcine coronary arteries. Vascular responses were examined by measuring isometric tension. Cyclic nucleotides were assayed by HPLC tandem mass spectroscopy. Rho kinase (ROCK) activity was determined by measuring the phosphorylation of myosin phosphatase target subunit 1 using Western blot analysis and an ELISA kit. The level of cIMP, but not that of cGMP, was elevated by hypoxia in arteries with, but not in those without, endothelium [except if treated with diethylenetriamine (DETA) NONOate]; the increases in cIMP were inhibited by the sGC inhibitor 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ). Hypoxia (Po2: 25–30 mmHg) augmented contractions of arteries with and without endothelium if treated with DETA NONOate; these hypoxic contractions were blocked by ODQ. In arteries without endothelium, hypoxic augmentation of contraction was also obtained with exogenous cIMP. In arteries with endothelium, hypoxic augmentation of contraction was further enhanced by inosine 5′-triphosphate, the precursor for cIMP. The augmentation of contraction caused by hypoxia or cIMP was accompanied by increased phosphorylation of myosin phosphatase target subunit 1 at Thr853, which was prevented by the ROCK inhibitor Y-27632. ROCK activity in the supernatant of isolated arteries was stimulated by cIMP in a concentration-dependent fashion. These results demonstrate that cIMP synthesized by sGC is the likely mediator of hypoxic augmentation of coronary vasoconstriction, in part by activating ROCK.
And the beat goes on: maintained cardiovascular function during aging in the longest-lived rodent, the naked mole-rat
Authors: Grimes Kelly M. , Reddy Anilkumar K. , Lindsey Merry L. , Buffenstein Rochelle
Published: June 2014

The naked mole-rat (NMR) is the longest-lived rodent known, with a maximum lifespan potential (MLSP) of >31 years. Despite such extreme longevity, these animals display attenuation of many age-associated diseases and functional changes until the last quartile of their MLSP. We questioned if such abilities would extend to cardiovascular function and structure in this species. To test this, we assessed cardiac functional reserve, ventricular morphology, and arterial stiffening in NMRs ranging from 2 to 24 years of age. Dobutamine echocardiography (3 μg/g ip) revealed no age-associated changes in left ventricular (LV) function either at baseline or with exercise-like stress. Baseline and dobutamine-induced LV pressure parameters also did not change. Thus the NMR, unlike other mammals, maintains cardiac reserve with age. NMRs showed no cardiac hypertrophy, evidenced by no increase in cardiomyocyte cross-sectional area or LV dimensions with age. Age-associated arterial stiffening does not occur since there are no changes in aortic blood pressures or pulse-wave velocity. Only LV interstitial collagen deposition increased 2.5-fold from young to old NMRs ( P < 0.01). However, its effect on LV diastolic function is likely minor since NMRs experience attenuated age-related increases in diastolic dysfunction in comparison with other species. Overall, these findings conform to the negligible senescence phenotype, as NMRs largely stave off cardiovascular changes for at least 75% of their MLSP. This suggests that using a comparative strategy to find factors that change with age in other mammals but not NMRs could provide novel targets to slow or prevent cardiovascular aging in humans.
Caloric restriction confers persistent anti-oxidative, pro-angiogenic, and anti-inflammatory effects and promotes anti-aging miRNA expression profile in cerebromicrovascular endothelial cells of aged rats
Authors: Csiszar Anna , Gautam Tripti , Sosnowska Danuta , Tarantini Stefano , Banki Eszter , Tucsek Zsuzsanna , Toth Peter , Losonczy Gyorgy , Koller Akos , Reglodi Dora , Giles Cory B. , Wren Jonathan D. , Sonntag William E. , Ungvari Zoltan
Published: June 2014

In rodents, moderate caloric restriction (CR) without malnutrition exerts significant cerebrovascular protective effects, improving cortical microvascular density and endothelium-dependent vasodilation, but the underlying cellular mechanisms remain elusive. To elucidate the persisting effects of CR on cerebromicrovascular endothelial cells (CMVECs), primary CMVECs were isolated from young (3 mo old) and aged (24 mo old) ad libitum-fed and aged CR F344xBN rats. We found an age-related increase in cellular and mitochondrial oxidative stress, which is prevented by CR. Expression and transcriptional activity of Nrf2 are both significantly reduced in aged CMVECs, whereas CR prevents age-related Nrf2 dysfunction. Expression of miR-144 was upregulated in aged CMVECs, and overexpression of miR-144 significantly decreased expression of Nrf2 in cells derived from both young animals and aged CR rats. Overexpression of a miR-144 antagomir in aged CMVECs significantly decreases expression of miR-144 and upregulates Nrf2. We found that CR prevents age-related impairment of angiogenic processes, including cell proliferation, adhesion to collagen, and formation of capillary-like structures and inhibits apoptosis in CMVECs. CR also exerts significant anti-inflammatory effects, preventing age-related increases in the transcriptional activity of NF-κB and age-associated pro-inflammatory shift in the endothelial secretome. Characterization of CR-induced changes in miRNA expression suggests that they likely affect several critical functions in endothelial cell homeostasis. The predicted regulatory effects of CR-related differentially expressed miRNAs in aged CMVECs are consistent with the anti-aging endothelial effects of CR observed in vivo. Collectively, we find that CR confers persisting anti-oxidative, pro-angiogenic, and anti-inflammatory cellular effects, preserving a youthful phenotype in rat cerebromicrovascular endothelial cells, suggesting that through these effects CR may improve cerebrovascular function and prevent vascular cognitive impairment.
Direct and indirect protection of right ventricular function by estrogen in an experimental model of pulmonary arterial hypertension
Authors: Liu Aiping , Schreier David , Tian Lian , Eickhoff Jens C. , Wang Zhijie , Hacker Timothy A. , Chesler Naomi C.
Published: June 2014

Pulmonary arterial hypertension (PAH) results in right ventricular (RV) dysfunction and failure. Paradoxically, women are more frequently diagnosed with PAH but have better RV systolic function and survival rates than men. The mechanisms by which sex differences alter PAH outcomes remain unknown. Here, we sought to study the role of estrogen in RV functional remodeling in response to PAH. The SU5416-hypoxia (SuHx) mouse model of PAH was used. To study the role of estrogen, female mice were ovariectomized and then treated with estrogen or placebo. SuHx significantly increased RV afterload and resulted in RV hypertrophy. Estrogen treatment attenuated the increase in RV afterload compared with the untreated group (effective arterial elastance: 2.3 ± 0.1 mmHg/μl vs. 3.2 ± 0.3 mmHg/μl), and this was linked to preserved pulmonary arterial compliance (compliance: 0.013 ± 0.001 mm2/mmHg vs. 0.010 ± 0.001 mm2/mmHg; P < 0.05) and decreased distal muscularization. Despite lower RV afterload in the estrogen-treated SuHx group, RV contractility increased to a similar level as the placebo-treated SuHx group, suggesting an inotropic effect of estrogen on RV myocardium. Consequently, when compared with the placebo-treated SuHx group, estrogen improved RV ejection fraction and cardiac output (ejection fraction: 57 ± 2% vs. 44 ± 2% and cardiac output: 9.7 ± 0.4 ml/min vs. 7.6 ± 0.6 ml/min; P < 0.05). Our study demonstrates for the first time that estrogen protects RV function in the SuHx model of PAH in mice directly by stimulating RV contractility and indirectly by protecting against pulmonary vascular remodeling. These results underscore the therapeutic potential of estrogen in PAH.
Nuclear RhoA signaling regulates MRTF-dependent SMC-specific transcription
Authors: Staus Dean P. , Weise-Cross Laura , Mangum Kevin D. , Medlin Matt D. , Mangiante Lee , Taylor Joan M. , Mack Christopher P.
Published: June 2014

We have previously shown that RhoA-mediated actin polymerization stimulates smooth muscle cell (SMC)-specific transcription by regulating the nuclear localization of the myocardin-related transcription factors (MRTFs). On the basis of the recent demonstration that nuclear G-actin regulates MRTF nuclear export and observations from our laboratory and others that the RhoA effector, mDia2, shuttles between the nucleus and cytoplasm, we investigated whether nuclear RhoA signaling plays a role in regulating MRTF activity. We identified sequences that control mDia2 nuclear-cytoplasmic shuttling and used mDia2 variants to demonstrate that the ability of mDia2 to fully stimulate MRTF nuclear accumulation and SMC-specific gene transcription was dependent on its localization to the nucleus. To test whether RhoA signaling promotes nuclear actin polymerization, we established a fluorescence recovery after photobleaching (FRAP)-based assay to measure green fluorescent protein-actin diffusion in the nuclear compartment. Nuclear actin FRAP was delayed in cells expressing nuclear-targeted constitutively active mDia1 and mDia2 variants and in cells treated with the polymerization inducer, jasplakinolide. In contrast, FRAP was enhanced in cells expressing a nuclear-targeted variant of mDia that inhibits both mDia1 and mDia2. Treatment of 10T1/2 cells with sphingosine 1-phosphate induced RhoA activity in the nucleus and forced nuclear localization of RhoA or the Rho-specific guanine nucleotide exchange factor (GEF), leukemia-associated RhoGEF, enhanced the ability of these proteins to stimulate MRTF activity. Taken together, these data support the emerging idea that RhoA-dependent nuclear actin polymerization has important effects on transcription and nuclear structure.
Growth of alveoli during postnatal development in humans based on stereological estimation
Authors: Herring Matt J. , Putney Lei F. , Wyatt Gregory , Finkbeiner Walter E. , Hyde Dallas M.
Published: June 2014

Alveolarization in humans and nonhuman primates begins during prenatal development. Advances in stereological counting techniques allow accurate assessment of alveolar number; however, these techniques have not been applied to the developing human lung. Based on the recent American Thoracic Society guidelines for stereology, lungs from human autopsies, ages 2 mo to 15 yr, were fractionated and isometric uniform randomly sampled to count the number of alveoli. The number of alveoli was compared with age, weight, and height as well as growth between right and left lungs. The number of alveoli in the human lung increased exponentially during the first 2 yr of life but continued to increase albeit at a reduced rate through adolescence. Alveolar numbers also correlated with the indirect radial alveolar count technique. Growth curves for human alveolarization were compared using historical data of nonhuman primates and rats. The alveolar growth rate in nonhuman primates was nearly identical to the human growth curve. Rats were significantly different, showing a more pronounced exponential growth during the first 20 days of life. This evidence indicates that the human lung may be more plastic than originally thought, with alveolarization occurring well into adolescence. The first 20 days of life in rats implies a growth curve that may relate more to prenatal growth in humans. The data suggest that nonhuman primates are a better laboratory model for studies of human postnatal lung growth than rats.
Reduced platelet-derived growth factor receptor expression is a primary feature of human bronchopulmonary dysplasia
Authors: Popova Antonia P. , Bentley J. Kelley , Cui Tracy X. , Richardson Michelle N. , Linn Marisa J. , Lei Jing , Chen Qiang , Goldsmith Adam M. , Pryhuber Gloria S. , Hershenson Marc B.
Published: June 2014

Animal studies have shown that platelet-derived growth factor (PDGF) signaling is required for normal alveolarization. Changes in PDGF receptor (PDGFR) expression in infants with bronchopulmonary dysplasia (BPD), a disease of hypoalveolarization, have not been examined. We hypothesized that PDGFR expression is reduced in neonatal lung mesenchymal stromal cells (MSCs) from infants who develop BPD. MSCs from tracheal aspirates of premature infants requiring mechanical ventilation in the first week of life were studied. MSC migration was assessed in a Boyden chamber. Human lung tissue was obtained from the University of Rochester Neonatal Lung Biorepository. Neonatal mice were exposed to air or 75% oxygen for 14 days. PDGFR expression was quantified by qPCR, immunoblotting, and stereology. MSCs were isolated from 25 neonates (mean gestational age 27.7 wk); 13 developed BPD and 12 did not. MSCs from infants who develop BPD showed lower PDGFR-α and PDGFR-β mRNA and protein expression and decreased migration to PDGF isoforms. Lungs from infants dying with BPD show thickened alveolar walls and paucity of PDGFR-α-positive cells in the dysmorphic alveolar septa. Similarly, lungs from hyperoxia-exposed neonatal mice showed lower expression of PDGFR-α and PDGFR-β, with significant reductions in the volume of PDGFR-α-positive alveolar tips. In conclusion, MSCs from infants who develop BPD hold stable alterations in PDGFR gene expression that favor hypoalveolarization. These data demonstrate that defective PDGFR signaling is a primary feature of human BPD.
Experimental Research into Technology of Abrasive Flow Machining Nonlinear Tube Runner
Authors: Li Junye , Yang Lifeng , Liu Weina , Zhang Xuechen , Sun Fengyu
Published: June 2014

In the fields of military and civil uses, some special passages exist in many major parts, such as non-linear tubes. The overall performance is usually decided by the surface quality. Abrasive flow machining (AFM) technology can effectively improve the surface quality of the parts. In order to discuss the mechanism and technology of abrasive flow machining nonlinear tube, the nozzle is picked up as the researching object, and the self-designed polishing liquid is employed to make research on the key technological parameters of abrasive flow machining linear tube. Technological parameters’ impact on surface quality of the parts through the nozzle surface topography and scanning electron microscopy (SEM) map is explored. It is experimentally confirmed that abrasive flow machining can significantly improve surface quality of nonlinear runner, and experimental results can provide technical reference to optimizing study of abrasive flow machining theory.
Dataset for Modelling Reaction Mechanisms Using Density Functional Theory: Mechanism of ortho‐Hydroxylation by High‐Valent Iron‐Oxo Species
Authors: Ansari Azaj , Rajaraman Gopalan
Published: June 2014

Modelling reaction mechanisms using density functional theory is one of the popular routes to underpin the course of a chemical reaction. Although numerous publications have come out in this area, the pitfall of modelling such reactions and explicitly publishing the entire data set (structures, energies, coordinates, spin densities, etc.) which lead to the conclusions are scarce. Here we have attempted to set a trend wherein all the computed data to underpin the reaction mechanism of ortho‐hydroxylation of aromatic compounds by high‐valent iron‐oxo complexes (FeIII–OOH, FeIV=O, and FeV=O) are collected. Since the structure, energetics and other details of the calculations can be employed in future to probe/understand the reactivity pattern of such species, establishing the data set is justified. Here by analysing the presented results we also discuss in brief the presented results.
Effects of Voltage-Gated K+Channel on Cell Proliferation in Multiple Myeloma
Authors: Wang Wei , Fan Yuying , Wang Shuye , Wang Lianjie , He Wanting , Zhang Qiu , Li Xiaoxia
Published: June 2014

Objective. To study the effects and underlying mechanisms of voltage-gated K+channels on the proliferation of multiple myeloma cells.Methods. RPMI-8226 MM cell line was used for the experiments. Voltage-gated K+currents and the resting potential were recorded by whole-cell patch-clamp technique. RT-PCR detected Kv channel mRNA expression. Cell viability was analyzed with MTT assay. Cell counting system was employed to monitor cell proliferation. DNA contents and cell volume were analyzed by flow cytometry.Results. Currents recorded in RPMI-8226 cells were confirmed to be voltage-gated K+channels. A high level of Kv1.3 mRNA was detected but no Kv3.1 mRNA was detected in RPMI-8226 cells. Voltage-gated K+channel blocker 4-aminopyridine (4-AP) (2 mM) depolarized the resting potential from −42 ± 1.7 mV to −31.8 ± 2.8 mV(P<0.01). The results of MTT assay showed that there was no significant cytotoxicity to RPMI-8226 cells when the 4-AP concentration was lower than 4 mM. 4-AP arrested cell cycle in G0/G1 phase. Cells were synchronized at the G1/S boundary by treatment of aphidicolin and released from the blockage by replacing the medium with normal culture medium or with culture medium containing 2 mM 4-AP. 4-AP produced no significant inhibitory effect on cell cycle compared with control cells(P>0.05).Conclusions. In RPMI-8226, voltage-gated K+channels are involved in proliferation and cell cycle progression its influence on the resting potential and cell volume may be responsible for this process; the inhibitory effect of the voltage-gated K+channel blocker on RPMI-8226 cell proliferation is a phase-specific event.
A Distributed Task Allocation Strategy for Collaborative Applications in Cluster-Based Wireless Sensor Networks
Authors: Wang Feng , Han Guangjie , Jiang Jinfang , Qiu Hao
Published: June 2014

Balancing energy consumption and prolonging network lifetime have been hot topics in energy limited wireless sensor networks (WSNs). It is generally known that multiple sensor nodes collaborating with each other to perform tasks are an important means of energy balancing. In addition, a reasonable task allocation strategy is also an efficient method for task performing and energy saving. Furthermore, in order to save energy consumption, many WSNs are organized into clusters. Therefore, in this paper, we propose a distributed task allocation strategy for collaborative applications (DTAC) in cluster-based WSNs. In DTAC, the service abilities of sensor nodes are first evaluated and then the sensor nodes are classified into different ranking domains. Based on the service abilities of cluster members, the service ability of each cluster is calculated. A complex task can be first allocated to several clusters, and then scheduled on collaborative cluster members. Simulation results demonstrate that, compared with current related works, DTAC is much more efficient for complex task processing in terms of reducing energy consumption, shortening execution time, and balancing network loads.
A Case of Primary Subglottic Malignant Melanoma with a Successful Surgical Treatment
Authors: Ahmad Shahzad , Abdelghany Mahmoud , Goldblatt Curtis , Stark Owen , Masciotra Nicholas
Published: June 2014

Primary subglottic malignant melanoma is a very rare and underdiagnosed neoplasm. We are reporting a case of primary malignant melanoma of subglottic mucosa in a 78-year-old woman who presented to our hospital with shortness of breath and hoarseness of voice. Laryngoscopy and excisional biopsy along with immunoreactivity to S-100 and human melanoma black-45 (HMB-45) confirmed the diagnosis. The patient was treated with laryngectomy followed by radiotherapy. Five years following surgical treatment, she continues to be asymptomatic. To our knowledge, there is only one reported case of primary malignant melanoma of subglottic mucosa in the medical literatures.
An Inducible Hepatocellular Carcinoma Model for Preclinical Evaluation of Antiangiogenic Therapy in Adult Mice
Authors: Runge Anja , Hu Junhao , Wieland Matthias , Bergeest Jan-Philip , Mogler Carolin , Neumann André , Géraud Cyrill , Arnold Bernd , Rohr Karl , Komljenovic Dorde , Schirmacher Peter , Goerdt Sergij , Augustin Hellmut G.
Published: June 2014

The limited availability of experimental tumor models that faithfully mimic the progression of human tumors and their response to therapy remains a major bottleneck to the clinical translation and application of novel therapeutic principles. To address this challenge in hepatocellular carcinoma (HCC), one of the deadliest and most common cancers in the world, we developed and validated an inducible model of hepatocarcinogenesis in adult mice. Tumorigenesis was triggered by intravenous adenoviral delivery of Cre recombinase in transgenic mice expressing the hepatocyte-specific albumin promoter, a loxP-flanked stop cassette, and the SV40 large T-antigen (iAST). Cre recombinase–mediated excision of the stop cassette led to a transient viral hepatitis and resulted in multinodular tumorigenesis within 5 to 8 weeks. Tumor nodules with histologic characteristics of human HCC established a functional vasculature by cooption, remodeling, and angiogenic expansion of the preexisting sinusoidal liver vasculature with increasing signs of vascular immaturity during tumor progression. Treatment of mice with sorafenib rapidly resulted in the induction of vascular regression, inhibition of tumor growth, and enhanced overall survival. Vascular regression was characterized by loss of endothelial cells leaving behind avascular type IV collagen–positive empty sleeves with remaining pericytes. Sorafenib treatment led to transcriptional changes of Igf1, Id1, and cMet over time, which may reflect the emergence of potential escape mechanisms. Taken together, our results established the iAST model of inducible hepatocarcinogenesis as a robust and versatile preclinical model to study HCC progression and validate novel therapies. Cancer Res; 74(15); 4157–69. ©2014 AACR.
Transient Ablation of Regulatory T cells Improves Antitumor Immunity in Colitis-Associated Colon Cancer
Authors: Pastille Eva , Bardini Katrin , Fleissner Diana , Adamczyk Alexandra , Frede Annika , Wadwa Munisch , von Smolinski Dorthe , Kasper Stefan , Sparwasser Tim , Gruber Achim D. , Schuler Martin , Sakaguchi Shimon , Roers Axel , Müller Werner , Hansen Wiebke , Buer Jan , Westendorf Astrid M.
Published: June 2014

Regulatory T cells (Treg) are supportive to cancer development in most tissues, but their role in colitis-associated colon cancer (CAC) remains unclear. In this study, we investigated the role of CD4+Foxp3+ Treg in a mouse model of CAC and in patients with colon cancer. These Treg were increased strongly in number in a mouse model of CAC and in the peripheral blood of patients with colon cancer, exhibiting an activated phenotype as defined by elevated expression of GARP, CD103, CTLA-4, and IL10, along with an increased suppressive effect on the proliferation and Th1 cytokine expression of CD4+CD25− responder T cells ex vivo. Transient ablation of CD4+Foxp3+ Treg during tumor development in the CAC model suppressed tumor outgrowth and distribution, accompanied by an increased number of CD8+IFNγ/granzyme B-producing effector T cells. Conversely, inactivation of IL10 in Treg did not elevate the antitumor response but instead further boosted tumor development. Our results establish a tumor-promoting function for Treg during CAC formation, but they also suggest that a selective, transient ablation of Treg can evoke antitumor responses, with implications for immunotherapeutic interventions in patients with CAC. Cancer Res; 74(16); 4258–69. ©2014 AACR.
A Regulatory Loop Involving miR-22, Sp1, and c-Myc Modulates CD147 Expression in Breast Cancer Invasion and Metastasis
Authors: Kong Ling-Min , Liao Cheng-Gong , Zhang Yang , Xu Jing , Li Yu , Huang Wan , Zhang Yi , Bian Huijie , Chen Zhi-Nan
Published: June 2014

Breast cancer is the most common cancer in women for which the metastatic process is still poorly understood. CD147 is upregulated in breast cancer and has been associated with tumor progression, but little is known about its regulatory mechanisms. In this study, we demonstrated that CD147 was overexpressed in breast cancer tissues and cell lines, and the high expression correlated with tumor invasion and metastasis. We also found that the transcription factors Sp1 and c-Myc could bind to the CD147 promoter and enhance its expression. The CD147 mRNA has a 748-bp 3′-untranslated region (UTR) with many miRNA target sites, suggesting possible regulation by miRNAs. We discovered that miR-22 repressed CD147 expression by directly targeting the CD147 3′UTR. We also determined that miR-22 could indirectly participate in CD147 modulation by downregulating Sp1 expression. miR-22 could form an autoregulatory loop with Sp1, which repressed miR-22 transcription by binding to the miR-22 promoter. Together with the c-Myc–mediated inhibition of miR-22 expression, our investigation identified a miR-22/Sp1/c-Myc network that regulates CD147 gene transcription. In addition, miR-22 overexpression suppressed breast cancer cell invasion, metastasis, and proliferation by targeting CD147 in vitro and in vivo. Furthermore, we found that miR-22 was significantly downregulated in breast cancer tissues and that its expression was inversely correlated with the tumor–node–metastasis stage and lymphatic metastasis in patients. Our study provides the first evidence that an miR-22/Sp1/c-Myc network regulates CD147 upregulation in breast cancer and that miR-22 represses breast cancer invasive and metastatic capacities. Cancer Res; 74(14); 3764–78. ©2014 AACR.
Hippo Coactivator YAP1 Upregulates SOX9 and Endows Esophageal Cancer Cells with Stem-like Properties
Authors: Song Shumei , Ajani Jaffer A. , Honjo Soichiro , Maru Dipen M. , Chen Qiongrong , Scott Ailing W. , Heallen Todd R. , Xiao Lianchun , Hofstetter Wayne L. , Weston Brian , Lee Jeffrey H. , Wadhwa Roopma , Sudo Kazuki , Stroehlein John R. , Martin James F. , Hung Mien-Chie , Johnson Randy L.
Published: June 2014

Cancer stem cells (CSC) are purported to initiate and maintain tumor growth. Deregulation of normal stem cell signaling may lead to the generation of CSCs; however, the molecular determinants of this process remain poorly understood. Here we show that the transcriptional coactivator YAP1 is a major determinant of CSC properties in nontransformed cells and in esophageal cancer cells by direct upregulation of SOX9. YAP1 regulates the transcription of SOX9 through a conserved TEAD binding site in the SOX9 promoter. Expression of exogenous YAP1 in vitro or inhibition of its upstream negative regulators in vivo results in elevated SOX9 expression accompanied by the acquisition of CSC properties. Conversely, shRNA-mediated knockdown of YAP1 or SOX9 in transformed cells attenuates CSC phenotypes in vitro and tumorigenicity in vivo. The small-molecule inhibitor of YAP1, verteporfin, significantly blocks CSC properties in cells with high YAP1 and a high proportion of ALDH1+. Our findings identify YAP1-driven SOX9 expression as a critical event in the acquisition of CSC properties, suggesting that YAP1 inhibition may offer an effective means of therapeutically targeting the CSC population. Cancer Res; 74(15); 4170–82. ©2014 AACR.
Molecular Pathways: The Basis for Rational Combination Using MEK Inhibitors in KRAS-Mutant Cancers
Authors: Okumura Shunsuke , Jänne Pasi A.
Published: June 2014

Mutations in RAS oncogenes are frequently observed in human cancers, and the mutations result in activation of the RAS–RAF–MEK–ERK pathway, leading to cell proliferation and survival. The pathway is, therefore, a potent therapeutic target in the RAS-mutant cancers. MEK inhibitors can specifically block the pathway and are one of the key types of drugs for the treatment of the RAS-mutant cancers. As RAS proteins activate other downstream signaling proteins in addition to the RAS–RAF–MEK–ERK pathway, combination therapeutic approaches with MEK inhibitors are also being evaluated. Moreover, MEK inhibitors can arrest cancer cells in G1 phase and repress prosurvival Bcl2 family proteins such as MCL1 and BCL2/BCLXL, and increase expression of Bim, a proapoptotic BH3-only family protein. This mechanism may explain the efficacy of the combination of MEK inhibitors with cytotoxic agents or other targeted inhibitors. A better understanding of the pathway will help us with development of rational combinations for the treatment of the RAS-mutant cancers. Clin Cancer Res; 20(16); 4193–9. ©2014 AACR.
Essential Role of Aldehyde Dehydrogenase 1A3 for the Maintenance of Non–Small Cell Lung Cancer Stem Cells Is Associated with the STAT3 Pathway
Authors: Shao Chunli , Sullivan James P. , Girard Luc , Augustyn Alexander , Yenerall Paul , Rodriguez-Canales Jaime , Liu Hui , Behrens Carmen , Shay Jerry W. , Wistuba Ignacio I. , Minna John D.
Published: June 2014

Purpose: Lung cancer stem cells (CSC) with elevated aldehyde dehydrogenase (ALDH) activity are self-renewing, clonogenic, and tumorigenic. The purpose of our study is to elucidate the mechanisms by which lung CSCs are regulated.

Experimental Design: A genome-wide gene expression analysis was performed to identify genes differentially expressed in the ALDH+ versus ALDH− cells. RT-PCR, Western blot analysis, and Aldefluor assay were used to validate identified genes. To explore the function in CSCs, we manipulated their expression followed by colony and tumor formation assays.

Results: We identified a subset of genes that were differentially expressed in common in ALDH+ cells, among which ALDH1A3 was the most upregulated gene in ALDH+ versus ALDH− cells. shRNA-mediated knockdown of ALDH1A3 in non–small cell lung cancer (NSCLC) resulted in a dramatic reduction in ALDH activity, clonogenicity, and tumorigenicity, indicating that ALDH1A3 is required for tumorigenic properties. In contrast, overexpression of ALDH1A3 by itself it was not sufficient to increase tumorigenicity. The ALDH+ cells also expressed more activated STAT3 than ALDH− cells. Inhibition of STAT3 or its activator EZH2 genetically or pharmacologically diminished the level of ALDH+ cells and clonogenicity. Unexpectedly, ALDH1A3 was highly expressed in female, never smokers, well-differentiated tumors, or adenocarcinoma. ALDH1A3 low expression was associated with poor overall survival.

Conclusions: Our data show that ALDH1A3 is the predominant ALDH isozyme responsible for ALDH activity and tumorigenicity in most NSCLCs, and that inhibiting either ALDH1A3 or the STAT3 pathway are potential therapeutic strategies to eliminate the ALDH+ subpopulation in NSCLCs. Clin Cancer Res; 20(15); 4154–66. ©2014 AACR.
Polymorphisms of Asparaginase Pathway and Asparaginase-Related Complications in Children with Acute Lymphoblastic Leukemia
Authors: Ben Tanfous Mohsen , Sharif-Askari Bahram , Ceppi Francesco , Laaribi Haithem , Gagné Vincent , Rousseau Julie , Labuda Malgorzata , Silverman Lewis B. , Sallan Stephen E. , Neuberg Donna , Kutok Jeffery L. , Sinnett Daniel , Laverdière Caroline , Krajinovic Maja
Published: June 2014

Purpose: Asparaginase (ASNase) is a standard and critical component in the therapy of childhood acute lymphoblastic leukemia (ALL), but it is also associated with several toxicities.

Experimental design: We recently reported the results of an association study between ASNase pathway genes and event-free survival (EFS) in childhood patients with ALL. The same polymorphisms were interrogated here in relation to allergies, pancreatitis, and thrombotic events following treatment with E. coli ASNase.

Results: Among patients of the discovery group, allergies, and pancreatitis were more frequent in individuals who are homozygous for the triple-repeat allele (3R) of the asparagine synthetase (ASNS) gene, resulting in remarkably higher risk of these toxicities associated with 3R3R genotype [OR for allergies, 14.6; 95% confidence interval (CI), 3.6–58.7; P < 0.0005 and OR for pancreatitis, 8.6; 95% CI, 2.0–37.3; P = 0.01]. In contrast, the ASNS haplotype *1 harboring double-repeat (2R) allele had protective effect against these adverse reactions (P ≤ 0.01). The same haplotype was previously reported to confer reduction in EFS. The risk effect of 3R3R genotype was not replicated in the validation cohort, whereas the protective effect of haplotype *1 against allergies was maintained (P ≤ 0.002). Analysis with additional polymorphisms in ASNS locus in lymphoblastoid cell lines showed that haplotype *1 is diversified in several subtypes of which one was associated with reduced in vitro sensitivity to ASNase (rs10486009, P = 0.01) possibly explaining an association seen in clinical setting.

Conclusions: This finding might have implication for treatment individualization in ALL and other cancers using asparagine depletion strategies. Clin Cancer Res; 21(2); 329–34. ©2014 AACR.

See related commentary by Avramis, p. 230
Inhibition of Tumor-Derived Prostaglandin-E2 Blocks the Induction of Myeloid-Derived Suppressor Cells and Recovers Natural Killer Cell Activity
Authors: Mao Yumeng , Sarhan Dhifaf , Steven André , Seliger Barbara , Kiessling Rolf , Lundqvist Andreas
Published: June 2014

Purpose: Increased frequencies of myeloid-derived suppressor cells (MDSC) correlate with poor prognosis in patients with cancers. Tumor-derived prostaglandin-E2 (PGE2) plays an important role in inducing MDSCs. However, the detailed mechanisms of this induction remain unknown. To develop targeted therapies for MDSCs, we sought to investigate the molecular basis of PGE2-regulated accumulation of MDSCs and their functional consequence on natural killer (NK) cell activity.

Experimental Design: The effects of PGE2 in inducing phenotypic, signaling, and functional alternations on monocytes were analyzed in vitro. Suppression of NK-cell activity by PGE2-treated monocytes was compared with that of freshly isolated CD14+HLA-DRlow/− monocytic MDSCs (moMDSC) from patients with melanoma. In addition, to explore the in vivo relevance of targeting PGE2 to reduce MDSC-mediated suppression of NK cells, we established a murine model, where tumor cells were disabled from cyclooxygenase-2 (COX-2) production.

Results: Patient-derived moMDSCs inhibited NK-cell activity through the production of TGFβ. In vitro, binding of PGE2 to EP2 and EP4 receptors on monocytes activated the p38MAPK/ERK pathway and resulted in elevated secretion of TGFβ. Similar to moMDSCs, PGE2-treated monocytes potently suppressed NK-cell activity through production of TGFβ. Furthermore, silencing COX-2 in murine 4T1 tumor cells reduced the accumulation of CD11b+Gr1+ MDSCs in the spleen, resulting in concomitant improved in vivo clearance of NK-cell sensitive YAC-1 cells.

Conclusions: Our results reveal an indispensable role of tumor-derived PGE2 in inducing MDSCs and suggest a favorable outcome of combining COX-2–targeted therapy and adoptive NK-cell transfer in patients with cancer. Clin Cancer Res; 20(15); 4096–106. ©2014 AACR.
Physical Activity, Obesity, Weight Change, and Risk of Atrial Fibrillation
Authors: Huxley Rachel R. , Misialek Jeffrey R. , Agarwal Sunil K. , Loehr Laura R. , Soliman Elsayed Z. , Chen Lin Y. , Alonso Alvaro
Published: June 2014

Background—

Physical activity (PA) has previously been suggested to attenuate the risk of atrial fibrillation (AF) conferred by excess body weight and weight gain. We prospectively examined the relationship between body size, weight change, and level of PA in a biracial cohort of middle-aged men and women.

Methods and Results—

Baseline characteristics on risk factor levels were obtained on 14 219 participants from the Atherosclerosis Risk in Communities Study. AF incidence was ascertained from 1987 to 2009. Adjusted Cox proportional hazards models were used to estimate the associations between body mass index, waist circumference, relative weight change, and PA level with incident AF. During follow-up, there were 1775 cases of incident AF. Body mass index and waist circumference were positively associated with AF as was weight loss/gain of >5% initial body weight. An ideal level of PA had a small protective effect on AF risk and partially attenuated the risk of AF associated with excess weight in men but not women: compared with men with a normal body mass index, the risk of AF in obese men with an ideal, intermediate, and poor level of PA at baseline was increased by 37%, 129%, and 156% (
P
interaction
=0.04). During follow-up, PA did not modify the association between weight gain and risk of AF.

Conclusions—

Obesity and extreme weight change are risk factors for incident AF, whereas being physically active is associated with a small reduction in risk. In men only, being physically active offset some, but not all, of the risk incurred with excess body weight.
Long-Term Follow-Up Shows Excellent Transmural Atrial Lead Performance in Patients With Complex Congenital Heart Disease
Authors: Williams Matthew R. , Shepard Suzanne M. , Boramanand Nicole K. , Lamberti John J. , Perry James C.
Published: June 2014

Background—

Many patients with congenital heart disease require permanent pacing for rhythm management but cannot undergo transvenous lead placement. In others, epicardial scarring prohibits adequate sensing and pacing thresholds using epicardial leads. This study describes long-term lead performance using a transmural atrial (epicardial to endocardial) pacing approach in patients with congenital heart disease.

Methods and Results—

For transmural atrial (TMA) lead access, a bipolar, steroid-eluting transvenous lead was placed from the epicardium via purse-string incision or atriotomy and affixed to atrial endocardium. Records were reviewed for patient data and acute and long-term lead performance for TMA leads placed 1998 to 2004. Forty-two of 48 TMA leads remain active at last follow-up. Two leads fractured, 4 were functional at >5-year follow-up but no longer active. Freedom from lead failure 98% (95% confidence interval, 86%–100%) at mean follow-up 7.8 years. TMA leads gave excellent sensing and pacing characteristics at implant and chronically. Median acute and chronic sensing thresholds were 3 and 2.8 mV, respectively; median acute and chronic pacing thresholds at 0.5 ms were 0.9 and 0.7 V, respectively. TMA leads performed similarly in Fontan patients. Overdrive pacing for intra-atrial re-entrant tachycardia was successful in 7 of 8 patients. One patient with high baseline risk died of stroke 7 years after implant. No lead-associated thrombi were observed.

Conclusions—

TMA pacing leads had excellent longevity, initial, and chronic functional properties and provide an alternative to epicardial leads in patients with congenital heart disease. Patients who cannot receive transvenous leads, have epicardial scarring or have intra-atrial re-entrant tachycardia could benefit most from routine use of this technique.
Impact of Empiric Nesiritide or Milrinone Infusion on Early Postoperative Recovery After Fontan Surgery
Authors: Costello John M. , Dunbar-Masterson Carolyn , Allan Catherine K. , Gauvreau Kimberlee , Newburger Jane W. , McGowan Francis X. , Wessel David L. , Mayer John E. , Salvin Joshua W. , Dionne Roger E. , Laussen Peter C.
Published: June 2014

Background—

We sought to determine whether empirical nesiritide or milrinone would improve the early postoperative course after Fontan surgery. We hypothesized that compared with milrinone or placebo, patients assigned to receive nesiritide would have improved early postoperative outcomes.

Methods and Results—

In a single-center, randomized, double-blinded, placebo-controlled, multi-arm parallel-group clinical trial, patients undergoing primary Fontan surgery were assigned to receive nesiritide, milrinone, or placebo. A loading dose of study drug was administered on cardiopulmonary bypass followed by a continuous infusion for ≥12 hours and ≤5 days after cardiac intensive care unit admission. The primary outcome was days alive and out of the hospital within 30 days of surgery. Secondary outcomes included measures of cardiovascular function, renal function, resource use, and adverse events. Among 106 enrolled subjects, 35, 36, and 35 were randomized to the nesiritide, milrinone, and placebo groups, respectively, and all were analyzed based on intention to treat. Demographics, patient characteristics, and operative factors were similar among treatment groups. No significant treatment group differences were found for median days alive and out of the hospital within 30 days of surgery (nesiritide, 20 [minimum to maximum, 0–24]; milrinone, 18 [0–23]; placebo, 20 [0–23];
P
=0.38). Treatment groups did not significantly differ in cardiac index, arrhythmias, peak lactate, inotropic scores, urine output, duration of mechanical ventilation, intensive care or chest tube drainage, or adverse events.

Conclusions—

Compared with placebo, empirical perioperative nesiritide or milrinone infusions are not associated with improved early clinical outcomes after Fontan surgery.

Clinical Trial Registration—

URL:
http://www.clinicaltrials.gov
. Unique identifier: NCT00543309.
Coronary Artery Disease Detected by Coronary Computed Tomographic Angiography Is Associated With Intensification of Preventive Medical Therapy and Lower Low-Density Lipoprotein Cholesterol
Authors: Hulten Edward , Bittencourt Marcio Sommer , Singh Avinainder , O’Leary Daniel , Christman Mitalee P. , Osmani Wafa , Abbara Suhny , Steigner Michael L. , Truong Quynh A. , Nasir Khurram , Rybicki Frank F. , Klein Josh , Hainer Jon , Brady Thomas J. , Hoffmann Udo , Ghoshhajra Brian B. , Hachamovitch Rory , Di Carli Marcelo F. , Blankstein Ron
Published: June 2014

Background—

Coronary computed tomographic angiography (CCTA) is an accurate test for the identification of coronary artery disease (CAD), yet the impact of CCTA results on subsequent medical therapy and risk factors has not been widely reported.

Methods and Results—

We identified consecutive patients aged >18 years without prior CAD who underwent CCTA from 2004 to 2011 and had complete data on medications before and after CCTA. CCTA results were categorized as no CAD, <50% stenosis, and ≥50% stenosis. Based on the number of involved segments, extent of disease was categorized as nonextensive (≤4 segments) or extensive CAD (>4 segments). Electronic medical records and patient interviews were reviewed blinded to CCTA findings to assess initiation of aspirin and intensification of lipid-lowering therapies. Survival analysis was performed to evaluate intensification of lipid therapy as a predictor of cardiovascular death or nonfatal myocardial infarction. Among 2839 patients with mean follow-up of 3.6 years, the odds of physician intensification of lipid-lowering therapy significantly increased for those with nonobstructive CAD (odds ratio, 3.6; 95% confidence interval, 2.9–4.9;
P
<0.001) and obstructive CAD (odds ratio, 5.6; 95% confidence interval, 4.3–7.3;
P
<0.001). Low-density lipoprotein cholesterol levels declined significantly in association with intensification of lipid-lowering therapy after CCTA in all patient subgroups. In a hypothesis-generating analysis, among patients with nonobstructive but extensive CAD, statin use after CCTA was associated with a reduction in cardiovascular death or myocardial infarction (hazards ratio, 0.18; 95% confidence interval, 0.05–0.66;
P
=0.01).

Conclusions—

Abnormal CCTA findings are associated with downstream intensification in statin and aspirin therapy. In particular, CCTA may lead to increased use of prognostically beneficial therapies in patients identified as having extensive, nonobstructive CAD.
Characterization of a Resident Population of Adventitial Macrophage Progenitor Cells in Postnatal Vasculature
Authors: Psaltis Peter J. , Puranik Amrutesh S. , Spoon Daniel B. , Chue Colin D. , Hoffman Scott J. , Witt Tyra A. , Delacroix Sinny , Kleppe Laurel S. , Mueske Cheryl S. , Pan Shuchong , Gulati Rajiv , Simari Robert D.
Published: June 2014

Rationale
:

Macrophages regulate blood vessel structure and function in health and disease. The origins of tissue macrophages are diverse, with evidence for local production and circulatory renewal.

Objective
:

We identified a vascular adventitial population containing macrophage progenitor cells and investigated their origins and fate.

Methods and Results
:

Single-cell disaggregates from adult C57BL/6 mice were prepared from different tissues and tested for their capacity to form hematopoietic colony-forming units. Aorta showed a unique predilection for generating macrophage colony-forming units. Aortic macrophage colony-forming unit progenitors coexpressed stem cell antigen-1 and CD45 and were adventitially located, where they were the predominant source of proliferating cells in the aortic wall. Aortic Sca-1
+
CD45
+
cells were transcriptionally and phenotypically distinct from neighboring cells lacking stem cell antigen-1 or CD45 and contained a proliferative (Ki67
+
) Lin
−
c-Kit
+
CD135
−
CD115
+
CX
3
CR1
+
Ly6C
+
CD11b
−
subpopulation, consistent with the immunophenotypic profile of macrophage progenitors. Adoptive transfer studies revealed that Sca-1
+
CD45
+
adventitial macrophage progenitor cells were not replenished via the circulation from bone marrow or spleen, nor was their prevalence diminished by depletion of monocytes or macrophages by liposomal clodronate treatment or genetic deficiency of macrophage colony-stimulating factor. Rather adventitial macrophage progenitor cells were upregulated in hyperlipidemic
ApoE
−/−
and
LDL-R
−/−
mice, with adventitial transfer experiments demonstrating their durable contribution to macrophage progeny particularly in the adventitia, and to a lesser extent the atheroma, of atherosclerotic carotid arteries.

Conclusions
:

The discovery and characterization of resident vascular adventitial macrophage progenitor cells provides new insight into adventitial biology and its participation in atherosclerosis and provokes consideration of the broader existence of local macrophage progenitors in other tissues.