tbuckley/cabot-search huggingface dataset:
Gene silencing in MCF-7 breast cancer cells by RNA interference
Authors: Fan Yang, Paul Meltzer
Journal: Cancer Research (2004)

1622   RNA interference (RNAi) is a gene silencing mechanism that is mediated by short interfering double-stranded RNA molecules (siRNA). Introduction of chemically synthesized siRNA or siRNA-expressing DNA vector into mammalian cells can induce degradation of the cognate mRNA. The RNAi technique has become a powerful tool for exploring gene function. The goal of this study is to use RNAi to perturb the level of individual components of breast cancer signaling pathways and determine the effects of these manipulations on gene expression using cDNA microarrays. Signal transduction in breast cancer is mediated by numerous genes, but the downstream targets of various signaling proteins are difficult to identify. RNAi provides a potential solution to this problem. To investigate the functions of genes that are associated with breast cancer, synthetic siRNAs have been used in this study to knock down gene expression of an individual gene. We are initially focusing on genes related to signaling through steroid receptors. The genes targeted by siRNA include estrogen receptor alpha (ESR1) and genes that are co-expressed in ESR1 positive cells, such as GATA-3 and AIB1. We have demonstrated that MCF-7 cells can be efficiently transfected with siRNA by lipofection or electroporation. However, lipofection of siRNA induces a strong interferon response in MCF-7 cells, while electroporation does not. Inhibition of gene expression was confirmed both at the protein level (by western blotting) and the mRNA level (by cDNA microarray profiling). Expression profiling of GATA-3 siRNA transfected cells indicates that there are GATA-3 specific changes at the mRNA level. Those changes are not due to off-target silencing, since they are shared by two siRNAs targeting different regions of the GATA-3 mRNA. The list of genes affected by GATA-3 knock-down include several that are associated with cell growth and morphology. These results demonstrate that RNAi can induce gene-specific changes and can be used to investigate the consequences of gene knock-down. By cross-referencing this data to a comprehensive database of genes regulated by hormone and growth factor related pathways in MCF-7, we will be able to obtain a broad picture of the role of multiple genes that mediate the growth and differentiation of breast cancer cells.
Pulsatile Stretch in Coronary Arteries Elicits Release of Endothelium-Derived Hyperpolarizing Factor
Authors: RüdigerPopp, IngridFleming, RudiBusse
Journal: Circulation Research (1998)

Abstract—To date, the release of the endothelium-derived hyperpolarizing factor (EDHF) has been demonstrated only in response to receptor-dependent Ca2+-elevating agonists. Since endothelial cells in situ are continuously subjected to rhythmic distension, we investigated the effect of rhythmic stretch on the release of EDHF from isolated porcine coronary arteries. In the combined presence of diclofenac and NG-nitro-l-arginine (L-NNA), sinusoidal pressure oscillations (from 40 to 50 mm Hg, 4 minutes, 1.5 Hz) led to simultaneous oscillations in the external diameter of coronary artery segments, the amplitude of which were decreased by iberiotoxin and apamin and also by endothelial denudation. In order to directly demonstrate the release of EDHF, the intraluminal solution from endothelium-intact coronary segments exposed to pulsatile stretch was applied to detector rat aortic smooth muscle cells, the membrane potential of which was continuously measured using the patch-clamp technique. The hyperpolarization ...
Potential Role of Hepatocyte Growth Factor, a Novel Angiogenic Growth Factor, in Peripheral Arterial Disease
Authors: Shin-ichiro Hayashi, Ryuichi Morishita, Shigefumi Nakamura, Kei Yamamoto, Atsushi Moriguchi, Tomokazu Nagano, Mutsuo Taiji, Hiroshi Noguchi, Kunio Matsumoto, Toshikazu Nakamura, Jitsuo Higaki, Toshio Ogihara
Journal: Circulation (1999)

Background —Although hepatocyte growth factor (HGF), a novel angiogenic growth factor, plays an important role in angiogenesis, regulation of local HGF production under hypoxia has not yet been clarified in vascular smooth muscle cells (VSMC) and endothelial cells (EC). Thus, we have studied the role of HGF in hypoxia-induced endothelial injury and the regulation of local vascular HGF expression in response to hypoxia. Methods and Results —HGF attenuated hypoxia-induced endothelial cell death. Importantly, hypoxic treatment of EC resulted in a significant decrease in local HGF production according to the severity of hypoxia and increased VEGF. Similarly, hypoxia significantly decreased in mRNA and protein of HGF and increased VEGF production in VSMC. In organ culture system, local HGF production was also significantly decreased by hypoxia ( P &lt;0.01). Downregulation of HGF by hypoxia is due to a significant decrease in cAMP, as hypoxic treatment decreased cAMP, a stimulator of HGF. Although active TGF-β, a suppressor of HGF, was increased at 72 hours after hypoxic treatment, treatment of anti-TGF-β antibody did not attenuate decreased HGF production. Finally, rHGF was intra-arterially administered into unilateral hind limb ischemia rabbits, to evaluate in vivo angiogenic activity. Of importance, a single intra-arterial administration of rHGF reduced severe necrosis due to ischemia in rabbit muscle, accompanied by a significant increase in angiographic score ( P &lt;0.01). Conclusions —Overall, these data demonstrated that hypoxic treatment of vascular cells significantly downregulated HGF production due to decreased cAMP, suggesting their potential roles in the pathophysiology of ischemic diseases. Moreover, administration of rHGF induced therapeutic angiogenesis, accompanied by improvement of necrotic changes in the ischemic hind limb model, as cytokine supplement therapy for peripheral arterial disease.
Abstract 18632: The Potent, Selective Cardiac Acetylcholine-Activated Potassium Current Inhibitor XEN-R0706 Prolongs Human Atrial Action Potential Duration
Authors: James Milnes, Simone Loose, Claire Poulet, Stephan Kuenzel, Said El-Haou, Claire Jackson, Raymond Tang, David Madge, John Ford, Ursula Ravens
Journal: Circulation (2013)

Aim: In the heart Kir3.1/3.4 conducts the acetylcholine-activated potassium current IKACh. Increased vagal-tone and constitutive-activation of IKACh are believed to be contributing factors to the substrate of atrial fibrillation (AF) in man. This study set out to characterise the novel drug XEN-R0706 and investigate its effect on human atrial IKACh and action potential duration (APD). Method: Ion channel pharmacology was investigated in whole-cell patch-clamp studies using either HEK293 or CHO cells expressing the ion channel gene of interest (~20°C) or isolated human atrial myocytes (37 °C). Action potentials were recorded (1Hz, 37 °C) from human atrial myocytes isolated from right atrial appendage obtained from consenting patients in sinus rhythm. The study was approved by the university ethics committee and complied with the declaration of Helsinki. Results: XEN-R0706 potently inhibited recombinant Kir3.1/3.4 (IC50 =30 nM, nH =0.7 ± 0.1) and had nominal effect on other cardiac channels displaying over 100-fold selectivity over hERG (IC50 3.3 μM, nH = 0.98 ± 0.1) and &gt;300-fold selectivity over Nav1.5, Cav1.2, Kir2.1, Kir6.2/SUR2A (IC50 &gt;&gt; 10 μM for each). In human right atrial cardiomyocytes, carbachol (CCh, 10 μM) activated IKACh from 6.8 ± 0.76 pA/pF to a maximum of 9.7 ± 0.9 pA/pF which quickly desensitized to 8.8 ± 0.8 pA/pF within 20 s (n=24). This current was completely inhibited by XEN-R0706 (0.3 - 3 μM) whereas basal IK1 was not affected. XEN-R0706 completely reversed the CCh-shortened APD in isolated atrial cardiomyocytes, i.e. mean APD90 values were: control 186.3 ± 20.3 ms, CCh (2 μM) 111.7 ± 11.1 ms (P&lt;0.05 vs control), CCh plus XEN-R0706 (1 μM) 168.2 ± 19.4 ms (P&lt;0.05 vs CCh, n=5). Conclusion: This is the first report of the effect of a potent, small-molecule inhibitor of IKACh on the human atrial APD. The selective IKACh inhibitor XEN-R0706 prolonged the CCh-shortened atrial APD90. Selective IKACh inhibitors have the potential to be new, safe and effective anti-arrhythmic therapies for the treatment of AF.
Abstract 40: The role of pressure-driven flow in invasion and chemoresistance of cancer cells in an engineered breast tumor model
Authors: Allison K. Simi, Andreas P. Kourouklis, Alexandra S. Piotrowski-Daspit, Joe Tien, Celeste M. Nelson
Journal: Cancer Research (2018)

Abstract Collapsed blood or lymphatic vessels in the tumor microenvironment often cause fluid buildup, leading to heterogeneous flow throughout the tissue. Here, we used a three-dimensional (3D) engineered tumor model to investigate how fluid flow specifically influences invasion and chemoresistance of breast cancer cells. To mimic breast tumors, we cultured aggregates of MDA-MB-231 human breast cancer cells embedded in 3D collagen channels. Collagen channels were flanked on the ends by two media reservoirs. By changing the relative heights of media in the reservoirs, we controlled the pressure-induced flow experienced by the tumor cell aggregate. We found that the direction of flow through the collagen channel determined the invasive phenotype of the engineered tumor. These analyses will be repeated with the addition of chemotherapy drugs taxol or 5-fluorouracil in the media to determine the effect of fluid flow on chemotherapeutic response. Our engineered tumor model provides insight into how physical forces influence the invasive phenotype of cancer cells. Citation Format: Allison K. Simi, Andreas P. Kourouklis, Alexandra S. Piotrowski-Daspit, Joe Tien, Celeste M. Nelson. The role of pressure-driven flow in invasion and chemoresistance of cancer cells in an engineered breast tumor model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 40.
Abstract IA19: Directing blood cancer therapy with mitochondrial BH3 profiling
Authors: Anthony G. Letai
Journal: Clinical Cancer Research (2017)

Abstract Connecting the right drugs to the right tumor is the fundamental job of cancer precision medicine. While there is a tendency to equate precision medicine with genomics, we are surrounded by examples where very effective modern targets are deployed effectively in disease without genomic guidance. One example is in chronic lymphocytic leukemia (CLL) where there have been several recent FDA approvals for drugs targeting CD20, PI3K, BTK, and BCL-2. Combinations of these highly active agents will likely dramatically alter practice, yet their discovery and assignment to CLL was not guided by genomics, as CLL generally lacks genetic alterations in any of these pathways. Instead, use in CLL was guided by the identification of vulnerabilities that had more to do with lineage than with genetics. In this talk, I will describe how my laboratory is using a probe of apoptotic signaling at the mitochondrion to identify drugs that provoke apoptotic signaling in cancer cells. This approach, called “BH3 profiling,” has so far been effective in guiding clinical trials of the BCL-2 inhibitor venetoclax in CLL and acute myelogenous leukemia. I will describe how we can deploy this tool as a predictive biomarker or as a discovery tool to directly identify drug vulnerabilities of cancer cells. Citation Format: Anthony G. Letai. Directing blood cancer therapy with mitochondrial BH3 profiling [abstract]. In: Proceedings of the Second AACR Conference on Hematologic Malignancies: Translating Discoveries to Novel Therapies; May 6-9, 2017; Boston, MA. Philadelphia (PA): AACR; Clin Cancer Res 2017;23(24_Suppl):Abstract nr IA19.
Abstract 18365: Bioengineered Silk Conduits Are Effective for Small Diameter Revascularization
Authors: ElysseFilipe, MiguelSantos, JuichienHung, JelenaRnjak-Kovacina, Martin KNg, Steven GWise
Journal: Circulation (2016)

Introduction: Currently available synthetic graft materials (ePTFE and Dacron) are inadequate for use for coronary artery bypass surgery, with uniform failure within 12 months. Silk fibroin is a versatile natural polymer with remarkable mechanical properties and tuneable biodegradation that is well tolerated in vivo. Small diameter silk grafts were engineered using electrospinning to obtain a woven mesh of silk nanofibers. Methods: Our silk materials are uniquely electrospun and subsequently cross-linked using water only, enhancing their biocompatibility. Following optimisation of mechanical properties and endothelialization, silk grafts and ePTFE controls were implanted into the abdominal aorta of rats with explant time points of 3, 6, 12 and 24 weeks (n=4). Results: In vitro, silk scaffolds enhanced endothelial cell proliferation ~ 5-fold, from day 1 to 6, significantly greater than ePTFE controls (p<0.01, n=14). Silk conduits demonstrated comparable elasticity to rat aorta (5.4±1.6MPa vs 2.1±1.0MPa, n=...
Abstract IA13: Systems approach to drug development
Authors: Gordon B. Mills
Journal: Clinical Cancer Research (2018)

Abstract One of the key lessons of the last century of cancer therapy is that combination therapy is, in most cases, necessary, particularly in advanced disease and complex epithelial tumors, to increase tumor control. However, as we have matured in the era of precision oncology which includes small-molecule targeted therapeutics and immuno-oncology agents, while response to targeted therapies are relatively frequent, durable responses are rare and in contrast responses to immuno-oncology agents are less frequent but are commonly durable and can approximate cures. It is thus clear that rational combination therapy approaches not only within a single modality but across different therapy approaches such as targeted and immunotherapy will be necessary to fulfill the promise of precision medicine. Indeed, in terms of the emerging fields of target therapy and immuno-oncology, we are at the end of the beginning. A number of monotherapies have demonstrated remarkable activity. However, only a portion of patients with our best biomarkers respond and responses are in general short for monotherapy with targeted therapies. Responses to immuno-oncology monotherapy and even initial attempts at combination therapy are extremely exciting in that although only subpopulations of patients still benefit, responses can be remarkably durable, approximating cures. Given the intrinsic heterogeneity of tumors as well as the many mechanisms underlying resistance to targeted and immunotherapy, the limited benefit from monotherapy is to be expected. The short term of response to therapy for most patients is due to a major degree to the almost inevitable emergence of resistance. We have used PARP inhibitors as an effective emerging therapy to explore genomic and adaptive mechanisms of resistance. Importantly, the tumor as well as the tumor ecosystem adapts to the stress induced by targeted or immunotherapy agents. These adaptive responses, which can be observed in tissue culture, animal models, and patient samples, offer therapeutic opportunities that can be targeted to increase the fraction of patients who will benefit as well as the depth and duration of responses. Based on this paradigm, we have identified a series of unexpected mechanisms of resistance to PARP inhibitors and have developed rational combination therapies to interdict emerging resistance. Based on these preclinical studies, we have promoted a number of therapies to clinical trials and have demonstrated exciting preliminary responses. Citation Format: Gordon B. Mills. Systems approach to drug development. [abstract]. In: Proceedings of the AACR Conference: Addressing Critical Questions in Ovarian Cancer Research and Treatment; Oct 1-4, 2017; Pittsburgh, PA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(15_Suppl):Abstract nr IA13.
Cilostazol Reduces Angiographic Restenosis After Endovascular Therapy for Femoropopliteal Lesions in the Sufficient Treatment of Peripheral Intervention by Cilostazol Study
Authors: OsamuIida, HiroyoshiYokoi, YoshimitsuSoga, NaotoInoue, KenjiSuzuki, YoshiakiYokoi, DaizoKawasaki, KanZen, KazushiUrasawa, YoshiakiShintani, AkiraMiyamoto, KeisukeHirano, YusukeMiyashita, TaketsuguTsuchiya, NorihikoShinozaki, MasatoNakamura, TakaakiIsshiki, ToshimitsuHamasaki, ShinsukeNanto
Journal: Circulation (2013)

Background—It remains unclear whether cilostazol, which has been shown to improve the clinical outcomes of endovascular therapy for femoropopliteal lesions, also reduces angiographic restenosis. Methods and Results—The Sufficient Treatment of Peripheral Intervention by Cilostazol (STOP-IC) study investigated whether cilostazol reduces the 12-month angiographic restenosis rate after percutaneous transluminal angioplasty with provisional nitinol stenting for femoropopliteal lesions. Two hundred patients with femoropopliteal lesions treated from March 2009 to April 2011 at 13 cardiovascular centers were randomly assigned 1:1 to receive oral aspirin with or without cilostazol. The primary end point was 12-month angiographic restenosis rate. Secondary end points were the restenosis rate on duplex ultrasound, the rate of major adverse cardiac events, and target lesion event-free survival. Researchers evaluated all follow-up data and assessed the end points in a blinded fashion. The mean lesion length and refere...
Abstract 295: Efficacy of MCL1 inhibitor S63845 in small cell lung cancer
Authors: Yuto Yasuda, Hiroaki Ozasa, Takahiro Tsuji, Takashi Nomizo, Tomoko Funazo, Hironori Yoshida, Yuichi Sakamori, Toyohiro Hirai, Young Hak Kim
Journal: Cancer Research (2018)

Abstract Lung cancer is the leading cause of cancer death. Small cell lung cancer (SCLC) is a histologic subtype of lung cancer and the proportion of SCLC is approximately 15%. New molecular targeted drugs and immune checkpoint inhibitors are successfully effective for non-small cell lung cancer. However, treatment of SCLC has not been improved over recent decades. It is important to explore new treatment strategies of SCLC. MCL1 is a member of the BCL-2 family, which regulates apoptosis. Targeting MCL1 represents a potential breakthrough of cancer treatment. We tested S63845, a MCL1 inhibitor, in four SCLC cell lines (DMS114, DMS53, SW1271, and NCI-H69) and, in addition, one patient derived SCLC cell (KTOR201). S63845 had greater efficacy in two of five SCLC cells (DMS114 and KTOR201). These two SCLC cells had higher expression of MCL1 and lower expression of BCL-XL, which is another member of the BCL-2 family. The other three SCLC cells (DMS53, SW1271 and NCI-H69) were resistant to S63845 and had a higher expression of BCL-XL or lower expression of MCL1. These data suggested that S63845 might be a powerful treatment of SCLC as a new therapeutic strategy. It is possible that the expressions of MCL1 and other members of the BCL-2 family predict the sensitivity of S63845. Citation Format: Yuto Yasuda, Hiroaki Ozasa, Takahiro Tsuji, Takashi Nomizo, Tomoko Funazo, Hironori Yoshida, Yuichi Sakamori, Toyohiro Hirai, Young Hak Kim. Efficacy of MCL1 inhibitor S63845 in small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 295.
Randomized, Double-Blind, Placebo-Controlled Trial of Oral Sirolimus for Restenosis Prevention in Patients With In-Stent Restenosis
Authors: JörgHausleiter, AdnanKastrati, JulindaMehilli, MichaelVogeser, DietlindZohlnhöfer, HelmutSchühlen, ChristophGoos, JürgenPache, FranzDotzer, GiselaPogatsa-Murray, JosefDirschinger, UweHeemann, AlbertSchömig
Journal: Circulation (2004)

Background— Despite recent advances in interventional cardiology, including the introduction of drug-eluting stents for de novo coronary lesions, the treatment of in-stent restenosis (ISR) remains a challenging clinical issue. Given the efficacy of systemic sirolimus administration to prevent neointimal hyperplasia in animal models and to halt and even reverse the progression of allograft vasculopathy, the aim of the present double-blind, placebo-controlled study was to evaluate the efficacy of a 10-day oral sirolimus treatment with 2 different loading regimens for the prevention of recurrent restenosis in patients with ISR. Methods and Results— Three hundred symptomatic patients with ISR were randomly assigned to 1 of 3 treatment arms: placebo or usual-dose or high-dose sirolimus. Patients received a cumulative loading dose of 0, 8, or 24 mg of sirolimus 2 days before and the day of repeat intervention followed by maintenance therapy of 2 mg/d for 7 days. Angiographic restenosis at 6-month angiography wa...
Apoptosis Signal-Regulating Kinase 1 Plays a Pivotal Role in Angiotensin II–Induced Cardiac Hypertrophy and Remodeling
Authors: YasuhiroIzumiya, ShokeiKim, YasukatsuIzumi, KaoruYoshida, MinoruYoshiyama, AtsushiMatsuzawa, HidenoriIchijo, HiroshiIwao
Journal: Circulation Research (2003)

Multiple lines of evidence establish that angiotensin II (Ang II) induces not only hypertension but also directly contributes to cardiac diseases. Apoptosis signal-regulating kinase 1 (ASK1), one of mitogen-activated protein kinase kinase kinases, plays a key role in stress-induced cellular responses. However, nothing is known about the role of ASK1 in cardiac hypertrophy and remodeling in vivo. In this study, by using mice deficient in ASK1 (ASK1−/− mice), we investigated the role of ASK1 in cardiac hypertrophy and remodeling induced by Ang II. Left ventricular (LV) ASK1 was activated by Ang II infusion in wild-type mice, which was mediated by angiotensin II type 1 receptor and superoxide. Although Ang II-induced hypertensive effect was comparable to wild-type and ASK1−/− mice, LV ASK1 activation by Ang II was not detectable in ASK1−/− mice, and p38 and c-Jun N-terminal kinase (JNK) activation was lesser in ASK−/− mice than in wild-type mice. Elevation of blood pressure by continuous Ang II infusion was ...
Reduced Ventricular Response Irregularity Is Associated With Increased Mortality in Patients With Chronic Atrial Fibrillation
Authors: AkiraYamada, JunichiroHayano, SeiichiroSakata, AkiyoshiOkada, SeijiMukai, NobuyukiOhte, GenjiroKimura
Journal: Circulation (2000)

Background—Variations in the ventricular response interval (VRI) during atrial fibrillation (AF) may be reduced in patients with adverse clinical outcomes. The properties of VRI dynamics associated with prognosis remain undetermined. Methods and Results—In 107 patients with chronic AF (age, 64±9 years), we analyzed a 24-hour ambulatory ECG for VRI variability (SD, SD of successive differences, and SD of 5-minute averages) and VRI irregularity (Shannon entropy of histogram, symbolic dynamics, and approximate entropy of beat-to-beat and minute-to-minute fluctuations [ApEnb-b and ApEnm-m]). During a follow-up period of 33±16 months, 18 patients died (17%), 9 from cardiac causes, 7 from fatal strokes, and 2 from malignancies. Reductions in all VRI variability and irregularity measures were associated with an increased risk for cardiac death but not for fatal stroke. A significant association with cardiac death was also found for ejection fraction (relative risk, 1.10; 95% confidence interval [CI], 1.04 to 1.1...