bluuebunny/crossref_metadata_2025 huggingface dataset:
Decoy receptor 3 inhibits renal mononuclear leukocyte infiltration and apoptosis and prevents progression of IgA nephropathy in mice
Authors: Ka Shuk-Man , Hsieh Tai-Tzu , Lin Shih-Hua , Yang Sung-Sen , Wu Chin-Chen , Sytwu Huey-Kang , Chen Ann
Published: September 2011

The progression of IgA nephropathy (IgAN), the most frequent type of primary glomerulonephritis, is associated with high levels of mononuclear leukocyte infiltration into the kidney. These cells consist mainly of T cells and macrophages. Our previous study showed that a decoy receptor 3 (DCR3) gene therapy can prevent the development of a mouse autoimmune glomerulonephritis model by its potent immune modulating effects (Ka SM, Sytwu HK, Chang DM, Hsieh SL, Tsai PY, Chen A. J Am Soc Nephrol 18: 2473–2485, 2007). Here, we tested the hypothesis that DCR3 might prevent the progression of IgAN, an immune complex-mediated primary glomerulonephritis, by inhibiting T cell activation, renal T cell/macrophage infiltration, and protecting the kidney from apoptosis. We used a progressive IgAN (Prg-IgAN) model in B cell-deficient mice, because the mice are characterized by a dramatic proliferation of activated T cells systemically and progressive NF-κB activation in the kidney. We treated the animals with short-term gene therapy with DCR3 plasmids by hydrodynamics-based gene delivery. When the mice were euthanized on day 21, we found that, compared with empty vector-treated (disease control) Prg-IgAN mice, DCR3 gene therapy resulted in 1) systemic inhibition of T cell activation and proliferation; 2) lower serum levels of proinflammatory cytokines; 3) improved proteinuria, renal function, and renal pathology (inhibiting the development of marked glomerular proliferation, crescent formation, glomerulosclerosis, and interstitial inflammation); 5) suppression of T cell and macrophage infiltration into the periglomerular interstitium of the kidney; and 5) a reduction in apoptotic figures in the kidney. On the basis of these findings, DCR3 might be useful therapeutically in preventing the progression of IgAN.
FXYD5 (dysadherin) regulates the paracellular permeability in cultured kidney collecting duct cells
Authors: Lubarski Irina , Asher Carol , Garty Haim
Published: September 2011

FXYD5 (dysadherin or RIC) is a member of the FXYD family of single-span transmembrane proteins associated with the Na+-K+-ATPase. Several studies have demonstrated enhanced expression of FXYD5 during metastasis and effects on cell adhesion and motility. The current study examines effects of FXYD5 on the paracellular permeability in the mouse kidney collecting duct cell line M1. Expressing FXYD5 in these cells leads to a large decrease in amiloride-insensitive transepithelial electrical resistance as well as increased permeability to 4-kDa dextran. Impairment of cell-cell contact was also demonstrated by staining cells for the tight and adherence junction markers zonula occludens-1 and β-catenin, respectively. This is further supported by large expansions of the interstitial spaces, visualized in electron microscope images. Expressing FXYD5 in M1 cells resulted in a decrease in N-glycosylation of β1 Na+-K+-ATPase, while silencing it in H1299 cells had an opposite effect. This may provide a mechanism for the above effects, since normal glycosylation of β1 plays an important role in cell-cell contact formation (Vagin O, Tokhtaeva E, Sachs G. J Biol Chem 281: 39573–39587, 2006).
AT1 receptor-mediated augmentation of angiotensinogen, oxidative stress, and inflammation in ANG II-salt hypertension
Authors: Lara Lucienne S. , McCormack Michael , Semprum-Prieto Laura C. , Shenouda Sylvia , Majid Dewan S. A. , Kobori Hiroyuki , Navar L. Gabriel , Prieto Minolfa C.
Published: September 2011

Augmentation of intrarenal angiotensinogen (AGT) synthesis, secretion, and excretion is associated with the development of hypertension, renal oxidative stress, and tissue injury during ANG II-dependent hypertension. High salt (HS) exacerbates hypertension and kidney injury, but the mechanisms remain unclear. In this study, we determined the consequences of HS intake alone compared with chronic ANG II infusion and combined HS plus ANG II on the stimulation of urinary AGT (uAGT), renal oxidative stress, and renal injury markers. Sprague-Dawley rats were subjected to 1) a normal-salt diet [NS, n = 5]; 2) HS diet [8% NaCl, n = 5]; 3) ANG II infusion in NS rats [ANG II 80 ng/min, n = 5]; 4) ANG II infusion in HS rats [ANG II+HS, n = 5]; and 5) ANG II infusion in HS rats treated with ANG II type 1 receptor blocker (ARB) [ANG II+HS+ARB, n = 5] for 14 days. Rats fed a HS diet alone did not show changes in systolic blood pressure (SBP), proteinuria, cell proliferation, or uAGT excretion although they did exhibit mesangial expansion, collagen deposition, and had increased NADPH oxidase activity accompanied by increased peroxynitrite formation in the kidneys. Compared with ANG II rats, the combination of ANG II infusion and a HS diet led to exacerbation in SBP (175 ± 10 vs. 221 ± 8 mmHg; P < 0.05), proteinuria (46 ± 7 vs. 127 ± 7 mg/day; P < 0.05), and uAGT (1,109 ± 70 vs.. 7,200 ± 614 ng/day; P < 0.05) associated with greater collagen deposition, mesangial expansion, interstitial cell proliferation, and macrophage infiltration. In both ANG II groups, the O2− levels were increased due to increased NADPH oxidase activity without concomitant increases in peroxynitrite formation. The responses in ANG II rats were prevented or ameliorated by ARB treatment. The results indicate that HS independently stimulates ROS formation, which may synergize with the effect of ANG II to limit peroxynitrite formation, leading to exacerbation of uAGT and greater injury during ANG II salt hypertension.
Hydration status affects urea transport across rat urothelia
Authors: Spector David A. , Deng Jie , Stewart Kerry J.
Published: September 2011

Although mammalian urinary tract epithelium (urothelium) is generally considered impermeable to water and solutes, recent data suggest that urine constituents may be reabsorbed during urinary tract transit and storage. To study water and solute transport across the urothelium in an in vivo rat model, we instilled urine (obtained during various rat hydration conditions) into isolated in situ rat bladders and, after a 1-h dwell, retrieved the urine and measured the differences in urine volume and concentration and total quantity of urine urea nitrogen and creatinine between instilled and retrieved urine in rat groups differing by hydration status. Although urine volume did not change >1.9% in any group, concentration (and quantity) of urine urea nitrogen in retrieved urine fell significantly (indicating reabsorption of urea across bladder urothelia), by a mean of 18% (489 mg/dl, from an instilled 2,658 mg/dl) in rats receiving ad libitum water and by a mean of 39% (2,544 mg/dl, from an instilled 6,204 mg/dl) in water-deprived rats, but did not change (an increase of 15 mg/dl, P = not significant, from an instilled 300 mg/dl) in a water-loaded rat group. Two separate factors affected urea nitrogen reabsorption rates, a urinary factor related to hydration status, likely the concentration of urea nitrogen in the instilled urine, and a bladder factor(s), also dependent on the animal's state of hydration. Urine creatinine was also absorbed during the bladder dwell, and hydration group effects on the concentration and quantity of creatinine reabsorbed were qualitatively similar to the hydration group effect on urea transport. These findings support the notion(s) that urinary constituents may undergo transport across urinary tract epithelia, that such transport may be physiologically regulated, and that urine is modified during transit and storage through the urinary tract.
Molecular regulation of NKCC2 in the thick ascending limb
Authors: Ares Gustavo R. , Caceres Paulo S. , Ortiz Pablo A.
Published: September 2011

The kidney plays an essential role in blood pressure regulation by controlling short-term and long-term NaCl and water balance. The thick ascending limb of the loop of Henle (TAL) reabsorbs 25–30% of the NaCl filtered by the glomeruli in a process mediated by the apical Na+-K+-2Cl−cotransporter NKCC2, which allows Na+and Cl−entry from the tubule lumen into TAL cells. In humans, mutations in the gene coding for NKCC2 result in decreased or absent activity characterized by severe salt and volume loss and decreased blood pressure (Bartter syndrome type 1). Opposite to Bartter's syndrome, enhanced NaCl absorption by the TAL is associated with human hypertension and animal models of salt-sensitive hypertension. TAL NaCl reabsorption is subject to exquisite control by hormones like vasopressin, parathyroid, glucagon, and adrenergic agonists (epinephrine and norepinephrine) that stimulate NaCl reabsorption. Atrial natriuretic peptides or autacoids like nitric oxide and prostaglandins inhibit NaCl reabsorption, promoting salt excretion. In general, the mechanism by which hormones control NaCl reabsorption is mediated directly or indirectly by altering the activity of NKCC2 in the TAL. Despite the importance of NKCC2 in renal physiology, the molecular mechanisms by which hormones, autacoids, physical factors, and intracellular ions regulate NKCC2 activity are largely unknown. During the last 5 years, it has become apparent that at least three molecular mechanisms determine NKCC2 activity. As such, membrane trafficking, phosphorylation, and protein-protein interactions have recently been described in TALs and heterologous expression systems as mechanisms that modulate NKCC2 activity. The focus of this review is to summarize recent data regarding NKCC2 regulation and discuss their potential implications in physiological control of TAL function, renal physiology, and blood pressure regulation.
Exercise lowers estrogen and progesterone levels in premenopausal women at high risk of breast cancer
Authors: Kossman D. A. , Williams N. I. , Domchek S. M. , Kurzer M. S. , Stopfer J. E. , Schmitz K. H.
Published: September 2011

Experimental and clinical data support a role for estrogens in the development and growth of breast cancer, and lowered estrogen exposure reduces breast cancer recurrence and new diagnoses in high-risk women. There is varied evidence that increased physical activity is associated with breast cancer risk reduction in both pre- and postmenopausal women, perhaps via lowered estrogen levels. The purpose of this study was to assess whether exercise intervention in premenopausal women at increased breast cancer risk reduces estrogen or progesterone levels. Seven healthy premenopausal women at high risk for breast cancer completed a seven-menstrual-cycle study. The study began with two preintervention cycles of baseline measurement of hormone levels via daily first-morning urine collection, allowing calculation of average area under the curve (AUC) hormone exposure across the menstrual cycle. Participants then began five cycles of exercise training to a maintenance level of 300 min per week at 80–85% of maximal aerobic capacity. During the last two exercise cycles, urinary estradiol and progesterone levels were again measured daily. Total estrogen exposure declined by 18.9% and total progesterone exposure by 23.7%. The declines were mostly due to decreased luteal phase levels, although menstrual cycle and luteal phase lengths were unchanged. The study demonstrated the feasibility of daily urine samples and AUC measurement to assess hormone exposure in experimental studies of the impact of interventions on ovarian hormones. The results suggest value in exercise interventions to reduce hormone levels in high-risk women with few side effects and the potential for incremental benefits to surgical or pharmacologic interventions.
An innovative work-loop calorimeter for in vitro measurement of the mechanics and energetics of working cardiac trabeculae
Authors: Taberner Andrew J. , Han June-Chiew , Loiselle Denis S. , Nielsen Paul M. F.
Published: September 2011

We describe a unique work-loop calorimeter with which we can measure, simultaneously, the rate of heat production and force-length work output of isolated cardiac trabeculae. The mechanics of the force-length work-loop contraction mimic those of the pressure-volume work-loops experienced by the heart. Within the measurement chamber of a flow-through microcalorimeter, a trabecula is electrically stimulated to respond, under software control, in one of three modes: fixed-end, isometric, or isotonic. In each mode, software controls the position of a linear motor, with feedback from muscle force, to adjust muscle length in the desired temporal sequence. In the case of a work-loop contraction, the software achieves seamless transitions between phases of length control (isometric contraction, isometric relaxation, and restoration of resting muscle length) and force control (isotonic shortening). The area enclosed by the resulting force-length loop represents the work done by the trabecula. The change of enthalpy expended by the muscle is given by the sum of the work term and the associated amount of evolved heat. With these simultaneous measurements, we provide the first estimation of suprabasal, net mechanical efficiency (ratio of work to change of enthalpy) of mammalian cardiac trabeculae. The maximum efficiency is at the vicinity of 12%.
Regional variation in the mechanical role of knee meniscus glycosaminoglycans
Authors: Sanchez-Adams Johannah , Willard Vincent P. , Athanasiou Kyriacos A.
Published: September 2011

High compressive properties of cartilaginous tissues are commonly attributed to the sulfated glycosaminoglycan (GAG) fraction of the extracellular matrix (ECM), but this relationship has not been directly measured in the knee meniscus, which shows regional variation in GAG content. In this study, biopsies from each meniscus region (outer, middle, and inner) were either subjected to chondroitinase ABC (CABC) to remove all sulfated GAGs or not. Compressive testing revealed that GAG depletion in the inner and middle meniscus regions caused a significant decrease in modulus of relaxation (58% and 41% decreases, respectively, at 20% strain), and all regions exhibited a significant decrease in viscosity (outer: 29%; middle: 58%; inner: 62% decrease). Tensile properties following CABC treatment were unaffected for outer and middle meniscus specimens, but the inner meniscus displayed significant increases in Young's modulus (41% increase) and ultimate tensile stress (40% increase) following GAG depletion. These findings suggest that, in the outer meniscus, GAGs contribute to increasing tissue viscosity, whereas in the middle and inner meniscus, where GAGs are most abundant, these molecules also enhance the tissue's ability to withstand compressive loads. GAGs in the inner meniscus also contribute to reducing the circumferential tensile properties of the tissue, perhaps due to the pre-stress on the collagen network from increased hydration of the ECM. Understanding the mechanical role of GAGs in each region of the knee meniscus is important for understanding meniscus structure-function relationships and creating design criteria for functional meniscus tissue engineering efforts.
TRPM8 acute desensitization is mediated by calmodulin and requires PIP2: distinction from tachyphylaxis
Authors: Sarria Ignacio , Ling Jennifer , Zhu Michael X. , Gu Jianguo G.
Published: September 2011

The cold-sensing channel transient receptor potential melastatin 8 (TRPM8) features Ca2+-dependent downregulation, a cellular process underlying somatosensory accommodation in cold environments. The Ca2+-dependent functional downregulation of TRPM8 is manifested with two distinctive phases, acute desensitization and tachyphylaxis. Here we show in rat dorsal root ganglion neurons that TRPM8 acute desensitization critically depends on phosphatidylinositol 4,5-bisphosphate (PIP2) availability rather than PIP2 hydrolysis and is triggered by calmodulin activation. Tachyphylaxis, on the other hand, is mediated by phospholipase hydrolysis of PIP2 and protein kinase C/phosphatase 1,2A. We further demonstrate that PIP2 switches TRPM8 channel gating to a high-open probability state with short closed times. Ca2+-calmodulin reverses the effect of PIP2, switching channel gating to a low-open probability state with long closed times. Thus, through gating modulation, Ca2+-calmodulin provides a mechanism to rapidly regulate TRPM8 functions in the somatosensory system.
Long-duration perforated patch recordings from spinal interneurons of adult mice
Authors: Husch Andreas , Cramer Nathan , Harris-Warrick Ronald M.
Published: September 2011

It has been very difficult to record from interneurons in acute slices of the lumbar spinal cord from mice >3 wk of age. The low success rate and short recording times limit in vitro experimentation on mouse spinal networks to neonatal and early postnatal periods when locomotor networks are still developmentally immature. To overcome this limitation and enable investigation of mature locomotor network neurons, we have established a reliable procedure to record from spinal cord neurons in slices from adult, behaviorally mature mice of any age. Two key changes to the established neonate procedure were implemented. First, we remove the cord by a dorsal laminectomy from a deeply anesthetized animal. This enables respiration and other vital functions to continue up to the moment the maximally oxygenated lumbar spinal cord is removed, improving the health of the slices. Second, since adult spinal cord interneurons appear more sensitive to the intracellular dialysis that occurs during whole cell recordings, we introduced perforated patch recordings to the procedure. Stable recordings up to 12 h in duration were obtained with our new method. This will allow investigation of changes in mature neuronal properties in disease states or after spinal cord injury and allow prolonged recordings of responses to drug application that were previously impossible.
Expression and functional properties of TRPM2 channels in dopaminergic neurons of the substantia nigra of the rat
Authors: Chung Kenny K. H. , Freestone Peter S. , Lipski Janusz
Published: September 2011

Transient receptor potential melastatin 2 (TRPM2) channels are sensitive to oxidative stress, and their activation can lead to cell death. Although these channels have been extensively studied in expression systems, their role in the brain, particularly in the substantia nigra pars compacta (SNc), remains unknown. In this study, we assessed the expression and functional properties of TRPM2 channels in rat dopaminergic SNc neurons, using acute brain slices. RT-PCR analysis revealed TRPM2 mRNA expression in the SNc region. Immunohistochemistry demonstrated expression of TRPM2 protein in tyrosine hydroxylase-positive neurons. Channel function was tested with whole cell patch-clamp recordings and calcium (fura-2) imaging. Intracellular application of ADP-ribose (50–400 μM) evoked a dose-dependent, desensitizing inward current and intracellular free calcium concentration ([Ca2+]i) rise. These responses were strongly inhibited by the nonselective TRPM2 channel blockers clotrimazole and flufenamic acid. Exogenous application of H2O2(1–5 mM) evoked a rise in [Ca2+]iand an outward current mainly due to activation of ATP-sensitive potassium (KATP) channels. Inhibition of K+conductance with Cs+and tetraethylammonium unmasked an inward current. The inward current and/or [Ca2+]irise were partially blocked by clotrimazole and N-( p-amylcinnamoyl)anthranilic acid (ACA). The H2O2-induced [Ca2+]irise was abolished in “zero” extracellular Ca2+concentration and was enhanced at higher baseline [Ca2+]i, consistent with activation of TRPM2 channels in the cell membrane. These results provide evidence for the functional expression of TRPM2 channels in dopaminergic SNc neurons. Given the involvement of oxidative stress in degeneration of SNc neurons in Parkinson's disease, further studies are needed to determine the pathophysiological role of these channels in the disease process.
A Rare Clinical Presentation of Intraoral Darier's Disease
Authors: Manoja K. G. D. , Siriwardena B. S. M. S. , Jayasooriya P. R. , Siriwardane D. J. L. , Tilakaratne W. M.
Published: September 2011

Darier's disease, also known as keratosis follicularis or dyskeratosis follicularis, is a rare disorder of keratinization. It is an autosomal dominant genodermatosis with high penetrance and variable expressivity. Its manifestation appears as hyperkeratotic papules primarily affecting seborrheic areas on the head, neck, thorax, and less frequently the oral mucosa. When oral manifestations are present, the palatal and alveolar mucosae are primarily affected. They usually asymptomatic and are discovered in routine dental examination. Histologically, the lesions present as suprabasal clefts in the epithelium with acantholytic and dyskeratotic cells represented by “corps ronds and grains.” This paper reports a case of an adult male patient who presented with painful whitish lesions on buccal mucosa with crusty lips as the only clinical sign of Darier's disease. As this patient did not have skin lesions or family history, an intraoral biopsy confirmed the diagnosis of Darier's disease by a multidisciplinary team.
Compassion Fatigue: An Application of the Concept to Informal Caregivers of Family Members with Dementia
Authors: Day Jennifer R. , Anderson Ruth A.
Published: September 2011

Introduction. Compassion fatigue is a concept used with increasing frequency in the nursing literature. The objective of this paper is to identify common themes across the literature and to apply these themes, and an existing model of compassion fatigue, to informal caregivers for family members with dementia.Findings. Caregivers for family members with dementia may be at risk for developing compassion fatigue. The model of compassion fatigue provides an informative framework for understanding compassion fatigue in the informal caregiver population. Limitations of the model when applied to this population were identified as traumatic memories and the emotional relationship between parent and child, suggesting areas for future research.Conclusions. Research is needed to better understand the impact of compassion fatigue on informal caregivers through qualitative interviews, to identify informal caregivers at risk for compassion fatigue, and to provide an empirical basis for developing nursing interventions for caregivers experiencing compassion fatigue.
The Effect of 50 000 IU Vitamin A with BCG Vaccine at Birth on Growth in the First Year of Life
Authors: Fisker Ane Bærent , Benn Christine Stabell , Diness Birgitte Rode , Martins Cesario , Rodrigues Amabelia , Aaby Peter , Bibby Bo Martin
Published: September 2011

Vitamin A supplements may interact with diphtheria-tetanus-pertussis (DTP) vaccine causing increased female mortality. In a randomised trial of neonatal vitamin A supplementation (VAS), we examined growth during the first year of life in 808 children, pursuing the hypothesis that a negative interaction between VAS and DTP in girls would be reflected in growth. Length and weight were measured at 6 weekly visits and WHO-growth-reference z-scores derived. Neonatal VAS had no effect on anthropometric measures at 12 months, but may interact sex differentially with routine vaccines. While BCG was the most recent vaccine, neonatal VAS benefitted growth (difference in weight-for-length z-score (dWFL: 0.31(95% CI: 0.03–0.59)). While DTP was the most recent vaccine, VAS tended to affect growth adversely in girls (dWFL = −0.21 (−0.48–0.06)). After measles vaccine (MV) there was no overall effect of neonatal VAS. The VAS effect differed significantly between the BCG and DTP windows (P=0.03), and the difference was borderline significant between the DTP and MV windows for girls (P=0.09).
The Use of a Scoring System to Guide Thromboprophylaxis in a High-Risk Pregnant Population
Authors: Schoenbeck D. , Nicolle A. , Newbegin K. , Hanley J. , Loughney A. D.
Published: September 2011

Guidelines for thromboprophylaxis in pregnancy are usually based upon clinical observations and expert opinion. For optimal impact, their use must be attended by consistency in the advice given to women. In this observational study, we evaluated the performance of a scoring system, used as a guide for clinicians administering dalteparin to pregnant women at increased risk of venous thromboembolism. The work included 47 women treated with dalteparin prior to adoption of the scoring system and 58 women treated with dalteparin after its adoption. The indication for thromboprophylaxis was recorded in each case together with details of the regimen employed, obstetric, and haematological outcomes. The main outcome measure was to determine whether consistency improved after adoption of the scoring system. We also recorded the occurrence of any new venous thromboembolism, haemorrhage, the use of regional anaesthesia during labour, evidence of allergy, and thrombocytopenia. We found that use of the scoring system improved the consistency of advice and increased the mean duration of thromboprophylaxis. None of the subjects suffered venous thromboembolism after assessment using the scoring system. There was no increase in obstetric or anaesthetic morbidity when dalteparin was given antenatally period and no evidence of heparin-induced thrombocytopenia.
Global Existence of the Higher‐Dimensional Linear System of Thermoviscoelasticity
Authors: Ma Zhiyong
Published: September 2011

We obtain a global existence result for the higher‐dimensional thermoviscoelastic
equations. Using semigroup approach, we will establish the global existence of
homogeneous, nonhomogeneous, linear, semilinear, and nonlinear, thermoviscoelastic systems.
Putative Factors That May Modulate the Effect of Exercise on Liver Fat: Insights from Animal Studies
Authors: Magkos Faidon
Published: September 2011

An increase in intrahepatic triglyceride (IHTG) content is the hallmark of nonalcoholic fatty liver disease (NAFLD) and is strongly associated with insulin resistance and dyslipidemia. Although regular aerobic exercise improves metabolic function, its role in regulating fat accumulation in the liver is incompletely understood, and human data are scarce. Results from exercise training studies in animals highlight a number of potential factors that could possibly mediate the effect of exercise on liver fat, but none of them has been formally tested in man. The effect of exercise on IHTG content strongly depends on the background diet, so that exercise is more effective in reducing IHTG under conditions that favor liver fat accretion (e.g., when animals are fed high-fat diets). Concurrent loss of body weight or visceral fat does not appear to mediate the effect of exercise on IHTG, whereas sex (males versus females), prandial status (fasted versus fed), and duration of training, as well as the time elapsed from the last bout of exercise could all be affecting the observed exercise-induced changes in IHTG content. The potential importance of these factors remains obscure, thus providing a wide array of opportunities for future research on the effects of exercise (and diet) on liver fat accumulation.
Preferences for Advance Directives in Korea
Authors: Kim So-Sun , Lee Won-Hee , Cheon JooYoung , Lee Jung-Eun , Yeo KiSun , Lee JuHee
Published: September 2011

Background. The goal of advance directives is to help patients retain their dignity and autonomy by making their own decisions regarding end-stage medical treatment. The purpose of this study was to examine preferences of advance directives among general population in Korea.Method. A descriptive cross-sectional survey was performed from October 2007 to June 2008 in Seoul, Korea. A total of 336 city-dwelling adults self-administered the questionnaire and returned it via mail. Data analyses were conducted using SPSS 17.0.Results. Subjects reported the need for healthcare providers' detailed explanations and recommendations regarding end-of-life care. When there is no hope of recovery and death is imminent, most subjects did not want to receive cardiopulmonary resuscitation nor an IV or tube feeding. However, most of the subjects wanted pain management care.Conclusions. The present study showed that many Korean people have an interest in advance directives. The results show that the autonomy and dignity of patient have increased in importance. To provide better end-of-life care, there is a need to educate patients on the definition and intent of an advance directive. Additional proactive communication between patients and their caregivers should be educated to healthcare providers.
STAT3 Is Necessary for Proliferation and Survival in Colon Cancer–Initiating Cells
Authors: Lin Li , Liu Aiguo , Peng Zhengang , Lin Huey-Jen , Li Pui-Kai , Li Chenglong , Lin Jiayuh
Published: September 2011

STAT3 is constitutively activated in colon cancer but its contributions in cancer-initiating cells have not been explored. In this study, we characterized STAT3 in aldehyde dehydrogenase (ALDH)-positive (ALDH+) and CD133-positive (CD133+) subpopulations of human colon tumor cells that exhibited more potent tumor-initiating ability than ALDH−/CD133− cells in tumor xenograft assays in mice. We found that ALDH+/CD133+ cells expressed higher levels of the active phosphorylated form of STAT3 than either ALDH−/CD133− or unfractionated colon cancer cells. STAT3 inhibition by RNA interference–mediated knockdown or small-molecule inhibitors LLL12 or Stattic blocked downstream target gene expression, cell viability, and tumorsphere-forming capacity in cancer-initiating cells. Similarly, treatment of mouse tumor xenografts with STAT3 short hairpin RNA (shRNA), interleukin 6 shRNA, or LLL12 inhibited tumor growth. Our results establish that STAT3 is constitutively activated in colon cancer–initiating cells and that these cells are sensitive to STAT3 inhibition. These findings establish a powerful rationale to develop STAT3 inhibitory strategies for treating advanced colorectal cancers. Cancer Res; 71(23); 7226–37. ©2011 AACR.
Tumor-Associated Macrophages Mediate Immunosuppression in the Renal Cancer Microenvironment by Activating the 15-Lipoxygenase-2 Pathway
Authors: Daurkin Irina , Eruslanov Evgeniy , Stoffs Taryn , Perrin George Q. , Algood Chester , Gilbert Scott M. , Rosser Charles J. , Su Li-Ming , Vieweg Johannes , Kusmartsev Sergei
Published: September 2011

Renal cell carcinoma (RCC), the most common human kidney cancer, is frequently infiltrated with tumor-associated macrophages (TAM) that can promote malignant progression. Here, we show that TAMs isolated from human RCC produce substantial amounts of the proinflammatory chemokine CCL2 and immunosuppressive cytokine IL-10, in addition to enhanced eicosanoid production via an activated 15-lipoxygenase-2 (15-LOX2) pathway. TAMs isolated from RCC tumors had a high 15-LOX2 expression and secreted substantial amounts of 15(S)-hydroxyeicosatetraenoic acid, its major bioactive lipid product. Inhibition of lipoxygenase activity significantly reduced production of CCL2 and IL-10 by RCC TAMs. In addition, TAMs isolated from RCC were capable of inducing in T lymphocytes, the pivotal T regulatory cell transcription factor forkhead box P3 (FOXP3), and the inhibitory cytotoxic T-lymphocyte antigen 4 (CTLA-4) coreceptor. However, this TAM-mediated induction of FOXP3 and CTLA-4 in T cells was independent of lipoxygenase and could not be reversed by inhibiting lipoxygenase activity. Collectively, our results show that TAMs, often present in RCCs, display enhanced 15-LOX2 activity that contributes to RCC-related inflammation, immunosuppression, and malignant progression. Furthermore, we show that TAMs mediate the development of immune tolerance through both 15-LOX2–dependent and 15-LOX2–independent pathways. We propose that manipulating LOX-dependent arachidonic acid metabolism in the tumor microenvironment could offer new strategies to block cancer-related inflammation and immune escape in patients with RCC. Cancer Res; 71(20); 6400–9. ©2011 AACR.
Definition of a FoxA1 Cistrome That Is Crucial for G1 to S-Phase Cell-Cycle Transit in Castration-Resistant Prostate Cancer
Authors: Zhang Chunpeng , Wang Liguo , Wu Dayong , Chen Hongyan , Chen Zhong , Thomas-Ahner Jennifer M. , Zynger Debra L. , Eeckhoute Jérôme , Yu Jindan , Luo Jun , Brown Myles , Clinton Steven K. , Nephew Kenneth P. , Huang Tim H.-M. , Li Wei , Wang Qianben
Published: September 2011

The enhancer pioneer transcription factor FoxA1 is a global mediator of steroid receptor (SR) action in hormone-dependent cancers. In castration-resistant prostate cancer (CRPC), FoxA1 acts as an androgen receptor cofactor to drive G2 to M-phase cell-cycle transit. Here, we describe a mechanistically distinct SR-independent role for FoxA1 in driving G1 to S-phase cell-cycle transit in CRPC. By comparing FoxA1 binding sites in prostate cancer cell genomes, we defined a codependent set of FoxA1-MYBL2 and FoxA1-CREB1 binding sites within the regulatory regions of the Cyclin E2 and E2F1 genes that are critical for CRPC growth. Binding at these sites upregulate the Cyclin E2 and Cyclin A2 genes in CRPC but not in earlier stage androgen-dependent prostate cancer, establishing a stage-specific role for this pathway in CRPC growth. Mechanistic investigations indicated that FoxA1, MYBL2, or CREB1 induction of histone H3 acetylation facilitated nucleosome disruption as the basis for codependent transcriptional activation and G1 to S-phase cell-cycle transit. Our findings establish FoxA1 as a pivotal driver of the cell-cycle in CRPC which promotes G1 to S-phase transit as well as G2 to M-phase transit through two distinct mechanisms. Cancer Res; 71(21); 6738–48. ©2011 AACR.
From Mice and Men to Earth and Space: Joint NASA–NCI Workshop on Lung Cancer Risk Resulting from Space and Terrestrial Radiation
Authors: Shay Jerry W. , Cucinotta Francis A. , Sulzman Frank M. , Coleman C. Norman , Minna John D.
Published: September 2011

On June 27–28, 2011, scientists from the National Cancer Institute (NCI), NASA, and academia met in Bethesda to discuss major lung cancer issues confronting each organization. For NASA, available data suggest that lung cancer is the largest potential cancer risk from space travel for both men and women and quantitative risk assessment information for mission planning is needed. In space, the radiation risk is from high energy and charge (HZE) nuclei (such as Fe) and high-energy protons from solar flares and not from gamma radiation. In contrast, the NCI is endeavoring to estimate the increased lung cancer risk from the potential widespread implementation of computed tomographic (CT) screening in individuals at high risk for developing lung cancer based on the National Lung Cancer Screening Trial (NLST). For the latter, exposure will be X-rays from CT scans from the screening (which uses “low-dose” CT scans) and also from follow-up scans used to evaluate abnormalities found during initial screening. Topics discussed included the risk of lung cancer arising after HZE particle, proton, and low-dose exposure to Earth's radiation. The workshop examined preclinical models, epidemiology, molecular markers, “omics” technology, radiobiology issues, and lung stem cells that relate to the development of lung cancer. Cancer Res; 71(22); 6926–9. ©2011 AACR.
Disruptive TP53 Mutation Is Associated with Aggressive Disease Characteristics in an Orthotopic Murine Model of Oral Tongue Cancer
Authors: Sano Daisuke , Xie Tong-Xin , Ow Thomas J. , Zhao Mei , Pickering Curtis R. , Zhou Ge , Sandulache Vlad C. , Wheeler David A. , Gibbs Richard A. , Caulin Carlos , Myers Jeffrey N.
Published: September 2011

Purpose: To characterize tumor growth and metastatic potential in head and neck squamous cell carcinoma (HNSCC) cell lines in an orthotopic murine model of oral tongue cancer and to correlate TP53 mutation status with these findings.

Experimental Design: Cells from each of 48 HNSCC cell lines were orthotopically injected into the oral tongues of nude mice. Tumor volume, cervical lymph node metastasis, and mouse survival were recorded. Direct sequencing of the TP53 gene and Western blot analysis for the p53 protein after induction with 5-fluorouracil was conducted. Cell lines were categorized as either mutant TP53 or wild-type TP53, and lines with TP53 mutation were further categorized on the basis of type of mutation (disruptive or nondisruptive) and level of p53 protein expression. The behavior of tumors in these different groups was compared.

Results: These 48 HNSCC cell lines showed a wide range of behavior from highly aggressive and metastatic to no tumor formation. Mice injected with cells harboring disruptive TP53 mutations had faster tumor growth, greater incidence of cervical lymph node metastasis, and shorter survival than mice injected with cells lacking these mutations.

Conclusions: HNSCC cell lines display a wide spectrum of behavior in an orthotopic model of oral cancer. Cell lines with disruptive TP53 mutations are more aggressive in this system, corroborating clinical reports that have linked these mutations to poor patient outcome. Clin Cancer Res; 17(21); 6658–70. ©2011 AACR.
Role of BRAF in Thyroid Oncogenesis
Authors: Caronia Lisa M. , Phay John E. , Shah Manisha H.
Published: September 2011

BRAF, a cytoplasmic serine–threonine protein kinase, plays a critical role in cell signaling as an activator within the mitogen-activated protein kinase (MAPK) pathway. The most common BRAF mutation is the V600E transversion, which causes constitutive kinase activity. This mutation has been found in a multitude of human cancers, including both papillary thyroid cancer (PTC) and papillary-derived anaplastic thyroid cancer (ATC), in which it initiates follicular cell transformation. With such a high frequency of BRAF mutations in PTC (44%) and PTC-derived ATC (24%), research in BRAFV600E detection for diagnostic purposes has shown high sensitivity and specificity for tumor cell presence. BRAFV600E in PTC has also provided valuable prognostic information, as its presence has been correlated with more aggressive and iodine-resistant phenotypes. Such findings have initiated research in targeting oncogenic BRAF in cancer therapeutics. Although multiple phase II clinical trials in patients with iodine-refractory metastatic PTC have shown significant efficacy for sorafenib, a first-generation BRAF inhibitor, the mechanism by which it mediates its effect remains unclear because of multiple additional kinase targets of sorafenib. Additionally, preclinical and clinical studies investigating combination therapy with agents such as selective (PLX 4032) and potent (BAY 73-4506 and ARQ 736) small-molecule BRAF inhibitors and MAP/extracellular signal-regulated kinase (ERK) kinase inhibitors (AZD6244) hold great promise in the treatment of BRAFV600E cancers and may eventually play a powerful role in changing the clinical course of PTC and ATC. Clin Cancer Res; 17(24); 7511–7. ©2011 AACR.
Preclinical Testing of PI3K/AKT/mTOR Signaling Inhibitors in a Mouse Model of Ovarian Endometrioid Adenocarcinoma
Authors: Wu Rong , Hu Tom C. , Rehemtulla Alnawaz , Fearon Eric R. , Cho Kathleen R.
Published: September 2011

Purpose: Genetically engineered mouse (GEM) models of ovarian cancer that closely recapitulate their human tumor counterparts may be invaluable tools for preclinical testing of novel therapeutics. We studied murine ovarian endometrioid adenocarcinomas (OEA) arising from conditional dysregulation of canonical WNT and PI3K/AKT/mTOR pathway signaling to investigate their response to conventional chemotherapeutic drugs and mTOR or AKT inhibitors.

Experimental Design: OEAs were induced by injection of adenovirus expressing Cre recombinase (AdCre) into the ovarian bursae of Apcflox/flox; Ptenflox/flox mice. Tumor-bearing mice or murine OEA-derived cell lines were treated with cisplatin and paclitaxel, mTOR inhibitor rapamycin, or AKT inhibitors API-2 or perifosine. Treatment effects were monitored in vivo by tumor volume and bioluminescence imaging, in vitro by WST-1 proliferation assays, and in OEA tissues and cells by immunoblotting and immunostaining for levels and phosphorylation status of PI3K/AKT/mTOR signaling pathway components.

Results: Murine OEAs developed within 3 weeks of AdCre injection and were not preceded by endometriosis. OEAs responded to cisplatin + paclitaxel, rapamycin, and AKT inhibitors in vivo. In vitro studies showed that response to mTOR and AKT inhibitors, but not conventional cytotoxic drugs, was dependent on the status of PI3K/AKT/mTOR signaling. AKT inhibition in APC−/Pten− tumor cells resulted in compensatory upregulation of ERK signaling.

Conclusions: The studies show the utility of this GEM model of ovarian cancer for preclinical testing of novel PI3K/AKT/mTOR signaling inhibitors and provide evidence for compensatory signaling, suggesting that multiple rather than single agent targeted therapy will be more efficacious for treating ovarian cancers with activated PI3K/AKT/mTOR signaling. Clin Cancer Res; 17(23); 7359–72. ©2011 AACR.
Ipilimumab: An Anti-CTLA-4 Antibody for Metastatic Melanoma
Authors: Lipson Evan J. , Drake Charles G.
Published: September 2011

Ipilimumab (MDX-010, Yervoy; Bristol-Myers Squibb), a fully human monoclonal antibody against CTL antigen 4 (CTLA-4), was recently approved by the U.S. Food and Drug Administration (FDA) for the treatment of metastatic melanoma. In both early- and late-phase trials, ipilimumab has shown consistent activity against melanoma. For example, in a randomized phase III trial that enrolled patients with previously treated metastatic disease, ipilimumab, with or without a peptide vaccine, improved overall survival: Median overall survival was 10.1 and 10.0 months in the ipilimumab and ipilimumab plus vaccine arms, respectively, versus 6.4 months in the vaccine-alone group (hazard ratio, 0.68; P ≤ 0.003). Serious (grade 3–5) immune-related adverse events occurred in 10% to 15% of patients. Thus, although it provides a clear survival benefit, ipilimumab administration requires careful patient monitoring and sometimes necessitates treatment with immune-suppressive therapy. Here, we review the mechanism of action, preclinical data, and multiple clinical trials that led to FDA approval of ipilimumab for metastatic melanoma. Clin Cancer Res; 17(22); 6958–62. ©2011 AACR.
Combining Curcumin (Diferuloylmethane) and Heat Shock Protein Inhibition for Neurofibromatosis 2 Treatment: Analysis of Response and Resistance Pathways
Authors: Angelo Laura S. , Wu Ji Yuan , Meng Feng , Sun Michael , Kopetz Scott , McCutcheon Ian E. , Slopis John M. , Kurzrock Razelle
Published: September 2011

Neurofibromatosis type 2 (NF2) is a genetic condition characterized by inactivation of the NF2 tumor suppressor gene and the development of schwannomas. The NF2 gene product, merlin, is activated (dephosphorylated) by contact inhibition and promotes growth suppression. We investigated the effect of curcumin (diferuloylmethane), a molecule with anti-inflammatory and antitumorigenic properties, on human schwannoma cell growth and the regulation of merlin by curcumin in both NF2 cells and neuroblastoma (non-NF2) cells. Curcumin inhibited the growth of HEI-193 schwannoma cells in vitro and downregulated the phosphorylation of Akt and extracellular signal–regulated kinase 1/2. Curcumin also activated MYPT1-pp1δ (a merlin phosphatase), which was associated with dephosphorylation of merlin on serine 518, an event that results in the folding of merlin to its active conformation. In addition, curcumin induced apoptosis and generated reactive oxygen species in HEI-193 cells. Consequently, hsp70 was upregulated at the mRNA and protein levels, possibly serving as a mechanism of escape from curcumin-induced apoptosis and growth inhibition. Endogenous merlin and hsp70 proteins interacted in HEI-193 schwannoma and SK-N-AS neuroblastoma cells. The combination of curcumin and an hsp inhibitor synergistically suppressed schwannoma cell growth. Our results provide a rationale for combining curcumin and KNK437 in the treatment of NF2. Mol Cancer Ther; 10(11); 2094–103. ©2011 AACR.
A New Phage-Display Tumor-Homing Peptide Fused to Antiangiogenic Peptide Generates a Novel Bioactive Molecule with Antimelanoma Activity
Authors: Matsuo Alisson L. , Juliano Maria A. , Figueiredo Carlos R. , Batista Wagner L. , Tanaka Aparecida S. , Travassos Luiz R.
Published: September 2011

Phage-display peptide libraries have been widely used to identify specific peptides targeting in vivo tumor cells and the tumor vasculature and playing an important role in the discovery of antitumor bioactive peptides. In the present work, we identified a new melanoma-homing peptide, (-CVNHPAFAC-), using a C7C phage-display library directed to the developing tumor in syngeneic mice. Phage were able to preferentially target melanoma in vivo, with an affinity about 50-fold greater than that with normal tissue, and the respective synthesized peptide displaced the corresponding phage from the tumor. A preferential binding to endothelial cells rather than to melanoma cells was seen in cell ELISA, suggesting that the peptide is directed to the melanoma vasculature. Furthermore, the peptide was able to bind to human sonic hedgehog, a protein involved in the development of many types of human cancers. Using a new peptide approach therapy, we coupled the cyclic peptide to another peptide, HTMYYHHYQHHL-NH2, a known antagonist of VEGFR-2 receptor, using the GYG linker. The full peptide CVNHPAFACGYGHTMYYHHYQHHL-NH2 was effective in delaying tumor growth (P < 0.05) and increasing animal survival when injected systemically, whereas a scramble-homing peptide containing the same antagonist did not have any effect. This is the first report on the synthesis of a tumor-homing peptide coupled to antiangiogenic peptide as a new anticancer therapeutics. Mol Cancer Res; 9(11); 1471–8. ©2011 AACR.
Fluorinated COX-2 Inhibitors as Agents in PET Imaging of Inflammation and Cancer
Authors: Uddin Md. Jashim , Crews Brenda C. , Ghebreselasie Kebreab , Huda Imran , Kingsley Philip J. , Ansari Mohammad Sib , Tantawy Mohammed N. , Reese Jeffery , Marnett Lawrence J.
Published: September 2011

COX-2 is a major contributor to the inflammatory response and cancer progression so it is an important target for prevention and therapy. COX-2 is absent or expressed at low levels in most epithelial cells but is found at high levels in inflammatory lesions, and many premalignant and malignant tumors. Thus, it is an attractive target for molecular imaging. We report a series of novel fluorinated imaging agents, derived from indomethacin or celecoxib that selectively inhibit COX-2. The most promising lead, compound 7, was a fluorinated derivative of celecoxib. Kinetic analysis revealed that this fluorinated compound is a slow, tight-binding inhibitor of COX-2 and exhibits minimal inhibitory activity against COX-1. Efficient incorporation of 18F into compound 7 by radiochemical synthesis and intravenous injection provided sufficient signal for in vivo positron emission tomography (PET) imaging. Selective uptake of 18F-7 was observed in inflamed rat paws compared with the noninflamed contralateral paws and uptake was blocked by pretreatment with the COX-2 inhibitor, celecoxib. Uptake of 18F-7 was not observed when inflammation was induced in COX-2–null mice. In nude mice bearing both a COX-2–expressing human tumor xenograft (1483) and a COX-2–negative xenograft (HCT116), 18F-7 selectively accumulated in the COX-2–expressing tumor. Accumulation was blocked by pretreatment of the animals with celecoxib. The in vitro and in vivo properties of compound 7 suggest it will be a useful probe for early detection of cancer and for evaluation of the COX-2 status of premalignant and malignant tumors. Cancer Prev Res; 4(10); 1536–45. ©2011 AACR.