Novel Therapeutic Approaches (novel + therapeutic_approach)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Reduction of Active Elastase Concentration by Means of Immobilized Inhibitors: A Novel Therapeutic Approach

BIOTECHNOLOGY PROGRESS, Issue 3 2004
Valentina Grano
The inhibitory power of three different active Nylon membranes, separately loaded with three different protease inhibitors, was studied with the aim of reducing the increased elastase concentration occurring during hemodialysis or extracorporeal blood circulation in patients undergoing cardiopulmonary bypass. Chemical grafting was carried out to make the inert Nylon membrane suitable for the immobilization of the inhibitors. The behavior of immobilized ,1 -antitrypsin, bovine pancreatic trypsin inhibitor (BPTI), or elastatinal was separately studied. ,1 -Antitrypsin and BPTI were covalently immobilized by means of a diazotization process, whereas elastatinal was covalently attached via a condensation process mediated by glutaraldehyde. The inhibitory power of each membrane type was studied as a function of the amount of immobilized inhibitor and temperature. All active membranes have shown good inhibitory power. The most efficient membrane was that loaded with ,1 -antitrypsin, the less efficient that with BPTI. [source]


Novel therapeutic approach to eradicate tyrosine kinase inhibitor resistant chronic myeloid leukemia stem cells

CANCER SCIENCE, Issue 7 2010
Kazuhito Naka
Although discovery of the tyrosine kinase inhibitor (TKI) imatinib mesylate has significantly improved the prognosis of chronic myeloid leukemia (CML) patients, a rare population of CML stem cells is known to be resistant to TKI therapy, causing recurrence of CML. However, recent progress in CML stem cell biology may present a novel therapeutic avenue for CML patients. In this review, we focus on mechanisms used by CML stem cells to maintain TKI-resistance. Comprehensive approaches including mouse genetics, prospective identification of CML stem cells, and syngenic transplantation techniques have identified several key molecules or signaling pathways, including hedgehog (Hh)/Smo, promyelocytic leukemia (PML), 5-lipoxygenase (5-LO), and forkhead box class O (FOXO), that function in CML stem cell maintenance. Inhibiting some of these factors in combination with TKI administration successfully antagonized resistance of CML stem cells to TKI therapy, resulting in efficient eradication of leukemia cells in vivo. Thus, development of methods that sensitize CML stem cells to TKI therapy may lead to novel therapies to treat CML patients. (Cancer Sci 2010) [source]


Invasive neuroendocrine carcinoma of the breast

CANCER, Issue 19 2010
A distinctive subtype of aggressive mammary carcinoma
Abstract BACKGROUND: Neuroendocrine carcinoma (NEC) of the breast, a pathologic entity newly defined in the 2003 World Health Organization classification of tumors, is a rare type of tumor that is not well recognized or studied. The purpose of this first case-controlled study is to reveal the clinicopathologic features, therapeutic response, and outcomes of patients with NEC of the breast. METHODS: Seventy-four patients with NEC of the breast who were treated at The University of Texas M. D. Anderson Cancer Center were analyzed; 68 of them had complete clinical follow-up. Two cohorts of invasive mammary carcinoma cases were selected to pair with NEC to reveal demographic, pathologic, and clinical features at presentation, along with therapeutic response to treatment and patient outcomes. RESULTS: NEC was more likely to be estrogen receptor/progesterone receptor positive and human epidermal growth factor receptor 2 negative. Despite similar age and disease stages at presentation, NEC showed a more aggressive course than invasive ductal carcinoma, with a higher propensity for local and distant recurrence and poorer overall survival. High nuclear grade, large tumor size, and regional lymph node metastasis were significant negative prognostic factors for distant recurrence-free survival; high nuclear grade and regional lymph node metastasis were also significant negative prognostic factors for overall survival. Although endocrine therapy and radiation therapy showed a trend toward improved survival, the small number of cases in this study limited the statistical power to reveal therapeutic benefits in NEC of the breast. CONCLUSIONS: NEC is a distinct type of aggressive mammary carcinoma. Novel therapeutic approaches should be explored for this uniquely different clinical entity. Cancer 2010. © 2010 American Cancer Society. [source]


Activity of HIV entry and fusion inhibitors expressed by the human vaginal colonizing probiotic Lactobacillus reuteri RC-14

CELLULAR MICROBIOLOGY, Issue 1 2007
Janice J. Liu
Summary Novel therapeutic approaches are needed to combat the rapid increase in HIV sexual transmission in women. The probiotic organism Lactobacillus reuteri RC-14 which safely colonizes the human vagina and prevents microbial infections, has been genetically modified to produce anti-HIV proteins which were capable of blocking the three main steps of HIV entry into human peripheral blood mononuclear cells. The HIV entry or fusion inhibitors were fused to the native expression and secretion signals of BspA, Mlp or Sep in L. reuteri RC-14 and the expression cassettes were stably inserted into the chromosome. L. reuteri RC-14 expressed the HIV inhibitors in cell wall-associated and secreted forms. L. reuteri RC-14 expressing CD4D1D2-antibody-like fusion proteins were able to bind single or dual tropic coreceptor-using HIV-1 primary isolates. This is the first study to show that a well-documented and proven human vaginal probiotic strain can express potent functional viral inhibitors, which may potentially lower the sexual transmission of HIV. [source]


B7-H1 up-regulation impairs myeloid DC and correlates with disease progression in chronic HIV-1 infection

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 11 2008
Xicheng Wang
Abstract Impaired myeloid dendritic cells (mDC) fail to elicit host antiviral immune responses, leading to disease progression in HIV-1 infection. However, mechanisms underlying mDC suppression remain elusive. In this study, we found that the T-cell co-stimulatory molecule programmed death-1 ligand-1 (B7-H1) is significantly up-regulated on peripheral mDC in HIV-1-infected typical progressors and AIDS patients, but is maintained at a relatively low level in long-term non-progressors. Successful immune reconstitution after highly active antiretroviral therapy, indicated by full suppression of HIV-1 replication and substantial increases of CD4 T-cell counts, correlated with a decrease in B7-H1 expression. Importantly, we also found that X4 HIV-1 isolates directly induced B7-H1 expression on mDC in vitro, while adding antiviral agents hampered this B7-H1 up-regulation. Blockade of B7-H1 in vitro strongly enhanced mDC-mediated allostimulatory capacity and IL-12 production. In contrast, B7-H1 ligation with soluble programmed death-1 (PD-1) reduced mDC maturation and IL-12 production but increased mDC apoptosis and IL-10 production. Thus, B7-H1 up-regulation may inhibit mDC-mediated immune response, thereby facilitating viral persistence and disease progression in HIV-1-infected patients. This study provides new evidence that B7-H1 inhibitory signaling may reversely mediate functional impairment of mDC in HIV-1 infection, which further supports the notion that B7-H1 blockade represents a novel therapeutic approach to this disease. [source]


Biliverdin therapy protects rat livers from ischemia and reperfusion injury

HEPATOLOGY, Issue 6 2004
Constantino Fondevila
Heme oxygenase (HO-1) provides a cellular defense mechanism during oxidative stress and catalyzes the rate-limiting step in heme metabolism that produces biliverdin (BV). The role of BV and its potential use in preventing ischemia/reperfusion injury (IRI) had never been studied. This study was designed to explore putative cytoprotective functions of BV during hepatic IRI in rat liver models of ex vivo perfusion and orthotopic liver transplantation (OLT) after prolonged periods of cold ischemia. In an ex vivo hepatic IRI model, adjunctive BV improved portal venous blood flow, increased bile production, and decreased hepatocellular damage. These findings were correlated with amelioration of histological features of IRI, as assessed by Suzuki's criteria. Following cold ischemia and syngeneic OLT, BV therapy extended animal survival from 50% in untreated controls to 90% to 100%. This effect correlated with improved liver function and preserved hepatic architecture. Additionally, BV adjuvant after OLT decreased endothelial expression of cellular adhesion molecules (P-selectin and intracellular adhesion molecule 1), and decreased the extent of infiltration by neutrophils and inflammatory macrophages. BV also inhibited expression of inducible nitric oxide synthase and proinflammatory cytokines (interleukin 1,, tumor necrosis factor ,, and interleukin 6) in OLTs. Finally, BV therapy promoted an increased expression of antiapoptotic molecules independently of HO-1 expression, consistent with BV being an important mediator through which HO-1 prevents cell death. In conclusion, this study documents and dissects potent cytoprotective effects of BV in well-established rat models of hepatic IRI. Our results provide the rationale for a novel therapeutic approach using BV to maximize the function and thus the availability of donor organs. (HEPATOLOGY 2004;40:1333,1341.) [source]


Glatiramer acetate: A novel therapeutic approach in Crohn's disease?

INFLAMMATORY BOWEL DISEASES, Issue 1 2009
Albrecht Neesse MD
No abstract is available for this article. [source]


Decrease in stromal androgen receptor associates with androgen-independent disease and promotes prostate cancer cell proliferation and invasion

JOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 6b 2008
Yirong Li
Abstract Androgen receptor (AR) is expressed in both stromal and epithelial cells of the prostate. The majority of studies on AR expression and function in prostate cancer is focused on malignant epithelial cells rather than stromal cells. In this study, we examined the levels of stromal AR in androgen-dependent and -independent prostate cancer and the function of stromal AR in prostate cancer growth and invasion. We showed that stromal AR levels were decreased in the areas surrounding cancerous tissue, especially in androgen-independent cancer. Using two telomerase-immortalized human stromal cell lines, one AR-positive and the other AR-negative, we demonstrated that stromal cells lacking AR stimulated cell proliferation of co-cultured prostate cancer cells in vitro and enhanced tumour growth in vivo when co-injected with PC3 epithelial cells in nude mice. In contrast, stromal cells expressing AR suppressed prostate cancer growth in vitro and in vivo. In parallel with cancer growth, in vitro invasion assays revealed that stromal cells lacking AR increased the invasion ability of PC3 cell by one order of magnitude, while stromal cells expressing AR reduced this effect. These results indicate a negative regulation of prostate cancer growth and invasion by stromal AR. This provides potentially new mechanistic insights into the failure of androgen ablation therapy, and the reactivation of stromal AR could be a novel therapeutic approach for treating hormone refractory prostate cancer. [source]


Ecabet sodium promotes the healing of trinitrobenzene-sulfonic-acid-induced ulceration by enhanced restitution of intestinal epithelial cells

JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7 2010
Tomohisa Takagi
Abstract Background and Aims:, Ecabet sodium (ES) is a gastric mucosal protective and ulcer-healing agent. Recently enema therapy with ES was found to be effective for the treatment of human ulcerative colitis as well as experimental colitis in an animal model. Whereas ES possesses potential as a novel treatment for ulcerative colitis, its precise mechanism of action remains to be elucidated. In this study, we investigated the therapeutic efficacy of ES in an experimental rat model of colitis, and evaluated the restitution of intestinal epithelial cells treated with ES in vitro. Methods:, Acute colitis was induced with trinitrobenzene sulfonic acid (TNBS) in male Wistar rats. Rats received intrarectal treatment with ES daily starting on day 7 and were sacrificed on day 14 after the administration of TNBS. The distal colon was removed to evaluate various parameters of inflammation. Moreover, wound-healing assays were used to determine the enhanced restitution of rat intestinal epithelial (RIE) cells treated with ES. Results:, Intracolonic administration of ES accelerated TNBS-induced ulcer healing. Increases in the wet weight of the colon after TNBS administration were significantly inhibited by ES treatment. The wound assay revealed ES enhancement of the migration of RIE cells migration through the phosphorylation of extracellular signal-regulated kinase. Conclusion:, Daily administration of an ES enema promoted the healing of intestinal mucosal injury, in part by the enhanced restitution of intestinal epithelial cells via extracellular signal-regulated kinase activation. ES may thus represent a novel therapeutic approach for the treatment of inflammatory bowel disease. [source]


Sonic Hedgehog signaling in the mammalian brain

JOURNAL OF NEUROCHEMISTRY, Issue 3 2010
Elisabeth Traiffort
J. Neurochem. (2010) 113, 576,590. Abstract The discovery of a Sonic Hedgehog (Shh) signaling pathway in the mature vertebrate CNS has paved the way to the characterization of the functional roles of Shh signals in normal and diseased brain. Shh is proposed to participate in the establishment and maintenance of adult neurogenic niches and to regulate the proliferation of neuronal or glial precursors in several brain areas. Consistent with its role during brain development, misregulation of Shh signaling is associated with tumorigenesis while its recruitement in damaged neural tissue might be part of the regenerating process. This review focuses on the most recent data of the Hedgehog pathway in the adult brain and its relevance as a novel therapeutic approach for brain diseases including brain tumors. [source]


PPAR, and PPAR, effectively protect against HIV-induced inflammatory responses in brain endothelial cells

JOURNAL OF NEUROCHEMISTRY, Issue 2 2008
Wen Huang
Abstract Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors which down-regulate inflammatory signaling pathways. Therefore, we hypothesized that alterations of PPAR functions can contribute to human immunodeficiency virus-1 (HIV-1)-induced dysfunction of brain endothelial cells. Indeed, treatment with HIV-1 transactivator of transcription (Tat) protein decreased PPAR transactivation in brain endothelial cells. We next stably over-expressed PPAR, and PPAR, in a newly developed cell line of human brain endothelial cells (hCMEC/D3 cells). Tat-induced up-regulation of inflammatory mediators, such as interleukin (IL)-1,, tumor necrosis factor-,, CCL2, and E-selectin were markedly attenuated in hCMEC/D3 over-expressing PPAR, or PPAR,. These results were confirmed in CCL2 and E-selectin promoter activity studies. Similar protective effects were observed in hCMEC/D3 after activation of PPAR, by exogenous PPAR agonists (dPGJ2 and rosiglitazone). PPAR over-expression also prevented Tat-induced binding activity and transactivation of nuclear factor-,B. Importantly, increased PPAR activity attenuated induction of IL-1,, tumor necrosis factor-,, CCL2, and E-selectin in hCMEC/D3 cells co-cultured with HIV-1-infected Jurkat cells. The protective effects of PPAR over-expression were reversed by the antagonists of PPAR, (MK886) or PPAR, (GW9662). The present data suggest that targeting PPAR signaling may provide a novel therapeutic approach to attenuate HIV-1-induced local inflammatory responses in brain endothelial cells. [source]


In vivo immunization following virus suppression: a novel approach for inducing immune control in chronic hepatitis B,

JOURNAL OF VIRAL HEPATITIS, Issue 1 2003
D. Sprengers
summary. Antiviral treatment of patients with active chronic hepatitis B may lead to significant reduction in morbidity and mortality. However, after stopping nucleoside therapy, relapse rates are high in those without acquired specific immunity. We have treated two chronic hepatitis B patients with in vivo immunization. In vivo immunization aims to optimize conditions for an effective immune response: following rapid and profound virus suppression by interferon-lamivudine combination therapy, lamivudine is withdrawn intermittently for 4 weeks during continued interferon therapy. In both patients with profound virus suppression a rapid rebound in viral replication was observed after lamivudine withdrawal; despite continued interferon. These periods of renewed viral replication were followed by rises in hepatitis activity. After re-introduction of lamivudine HBV DNA became undetectable by PCR followed by normalization of serum ALT. These observations are a stimulus to further explore the concept of in vivo immunization as a novel therapeutic approach for chronic hepatitis B. [source]


Chemokine receptor antagonists: a novel therapeutic approach in allergic diseases

ALLERGY, Issue 12 2004
J. Elsner
The aim of this review is to give an overview of the role of chemokines, particularly ligands of the CC chemokine receptor CCR3, in allergic diseases and to show the new concept in the treatment of allergies using chemokine receptor antagonists. Allergic diseases such as allergic asthma, allergic rhinitis and atopic dermatitis are characterized by a complex interaction of different cell types and mediators. Among this, Th2 cells, mast cells, basophils and eosinophils are found in the inflamed tissue due to the attraction of chemokines. Of all the known chemokine receptors, the chemokine receptor CCR3 seems to play the major role in allergic diseases which is supported by the detection of this receptor on the cell types mentioned above. Therefore, academic and industrial research focus on compounds to block this receptor. To date, certain chemokine receptor antagonists derived from peptides and small molecules exist to block the chemokine receptor CCR3. However, the in vivo data about these compounds and the mechanisms of receptor interaction are poorly understood, as yet. For the development of additional chemokine receptor antagonists, more details about the interaction between the ligands and their receptors are required. Therefore, additional studies will lead to the identification of novel CCR3 chemokine receptor antagonists, which can be therapeutically used in allergic asthma, allergic rhinitis, and atopic dermatitis. [source]


Translational experimental therapeutics: The translation of laboratory-based discovery into disease-related therapy

MOUNT SINAI JOURNAL OF MEDICINE: A JOURNAL OF PERSONALIZED AND TRANSLATIONAL MEDICINE, Issue 1 2007
Karl Kieburtz MD
Abstract In the past decade, there has been an increasing emphasis on laboratory-based translational research. This has led to significant scientific advances in our understanding of disease mechanisms and in the development of novel approaches to therapy such as gene therapy, RNA interference, and stem cells. However, the translation of these remarkable scientific achievements into new and effective disease-modifying therapies has lagged behind these scientific accomplishments. We use the term "translational experimental therapeutics" to describe the pathway between the discovery of a basic disease mechanism or novel therapeutic approach and its translation into an effective treatment for patients with a specific disease. In this article, we review the components of this pathway, and discuss issues that might impede this process. Only by optimizing this pathway can we realize the full therapeutic potential of current scientific discoveries and translate the astounding advances that have been accomplished in the laboratory into effective treatments for our patients. Mt Sinai J Med 74: 7-14, 2007. Copyright © 2007 Mount Sinai School of Medicine [source]


Topiramate reduces levodopa-induced dyskinesia in the MPTP-lesioned marmoset model of Parkinson's disease

MOVEMENT DISORDERS, Issue 4 2005
Monty A. Silverdale MRCP
Abstract Overactive AMPA receptor-mediated transmission may be involved in the pathogenesis of levodopa-induced dyskinesia. The mechanism of action of the anticonvulsant drug topiramate involves attenuation of AMPA receptor-mediated transmission. In this study, the potential antidyskinetic action of topiramate was examined in the MPTP-lesioned marmoset model of Parkinson's disease and levodopa-induced dyskinesia. Topiramate significantly reduced levodopa-induced dyskinesia, without affecting the antiparkinsonian action of levodopa. Topiramate represents an exciting potential novel therapeutic approach to levodopa-induced dyskinesia in patients with Parkinson's disease. © 2004 Movement Disorder Society [source]


Cytotoxicity and antiangiogenesis by fibroblast growth factor 2,targeted Ad-TK cancer gene therapy,

THE LARYNGOSCOPE, Issue 4 2009
Koichiro Saito MD
Abstract Objectives: Human head and neck squamous cell carcinoma (HNSCC) in addition to lung, skin, ovarian, and other cancers overexpress fibroblast growth factor (FGF) receptors on both individual tumor cells and endothelial cells within the tumor microenvironment. The purpose of this study was to investigate whether FGF2-targeted gene therapy could redirect adenoviral vectors encoding the herpes simplex virus thymidine kinase gene (Ad-TK) to FGF receptors on tumor and endothelial cells with the intent of improving both the efficiency of transgene expression and the antitumor response. Study Design and Methods: An Ad-TK vector consisting of a conjugate of FGF2 linked to a Fab, fragment against the adenoviral knob region was directly delivered to human HNSCC xenograft tumors in nude mice, which were subsequently dosed with ganciclovir. Tumor specimens were assessed for herpes simplex virus thymidine kinase (HSV- tk) transgene mRNA expression, FGF1/2 receptor expression, terminal deoxynucleotidyl transferase biotin,deoxy uridine triphosphate nick end labeling assay for apoptosis, CD31 immunohistochemistry to estimate tumor microvessel density, and tumor volume change. Results: FGF2-retargeted Ad-TK gene therapy demonstrated significant increases in both HSV- tk mRNA expression and cellular apoptosis levels, and a significant decrease in tumor volume size compared with all other groups. Furthermore, microvessel density was significantly lower in the FGF2-retargeted Ad-TK group, indicating a strong antiangiogenesis effect. Conclusions: These data suggest that FGF2-retargeted Ad-TK produces a combination of expected direct antitumor cytotoxicity and a newly reported antiangiogenesis effect that could prove promising as a novel therapeutic approach in the treatment of FGF receptor,expressing cancers. Laryngoscope, 2009 [source]


Nasal Allergic Response Mediated by Histamine H3 Receptors in Murine Allergic Rhinitis

THE LARYNGOSCOPE, Issue 10 2005
Muneo Nakaya MD
Abstract Background: Histamine is one of the most important chemical mediators causing nasal allergic symptoms, and H1 receptor antagonist have been used as the treatment first choice in nasal allergy. The presence of H3 receptors has also been determined in the human nasal mucosa, but few studies have investigated the involvement of H3 receptors in nasal allergy. Objective: We used a murine allergic model to investigate the presence of nasal mucosa H3 receptor mRNA and any H3 receptor agonist or antagonist influences on clinical nasal allergic symptoms. Methods: H3 receptor mRNA in nasal mucosa was investigated by reverse-transcription polymerase chain reaction. OVA-sensitized mice were given an intraperitoneal injection of H3 receptor agonist or antagonist, and clinical nasal allergic symptoms were scored over 10 minutes after nasal provocation of OVA. Inhibition of nasal allergic symptoms was also examined using an H1 receptor antagonist alone and using a both an H3 receptor agonist and an H1 receptor antagonist. Results: H3 receptor mRNA was identified in the murine nasal mucosa. The H3 receptor agonist (R)-,-metylhistamine significantly inhibited clinical nasal allergic symptoms of OVA-sensitized mice. The H3 receptor agonist and H1 receptor antagonist inhibited clinical nasal allergic symptoms in the murine allergic model more strongly than the single drug. Conclusion: The foregoing results indicate that H3 receptors are involved in modulation of nasal allergy. H3 receptor agonists can also be useful as a novel therapeutic approach in nasal allergy. Both H3 receptor agonist and H1 receptor antagonist may be more effective than a single drug. [source]


Effects of combined inhibition of the Na+,H+ exchanger and angiotensin-converting enzyme in rats with congestive heart failure after myocardial infarction

BRITISH JOURNAL OF PHARMACOLOGY, Issue 5 2005
Hartmut Ruetten
We investigated the single vs the combined long-term inhibition of Na+,H+ exchanger-1 (NHE-1) and ACE in rats with congestive heart failure induced by myocardial infarction (MI). Rats with MI were randomized to receive either placebo, cariporide (3000 p.p.m. via chow), ramipril (1 mg kg,1 day,1via drinking water) or their combination for 18 weeks starting on day 3 after surgery. Cardiac morphology and function was assessed by echocardiography and by means of a 2.0 F conductance catheter to determine left ventricular (LV) pressure volume relationships. MI for 18 weeks resulted in an increase in LV end-diastolic diameter (LVDed) in the placebo-treated group when compared to sham (placebo: 1.1±0.04 cm; sham: 0.86±0.01; P<0.05). Combined inhibition of NHE-1 and ACE, but not the monotherapies, significantly reduced LVDed (1.02±0.02 cm). Preload recruitable stroke work (PRSW), dp/dtmax (parameter of systolic function) and end-diastolic pressure volume relationship (EDPVR, diastolic function) were significantly impaired in placebo-treated MI group (PRSW: 39±7 mmHg; dp/dtmax: 5185±363 mmHg s,1; EDPVR: 0.042±0.001 mmHg ,l,1; all P<0.05). Cariporide treatment significantly improved PRSW (64±7 mmHg), dp/dtmax (8077±525 mmHg s,1) and EDPVR (0.026±0.014 mmHg ,l,1), and reduced cardiac hypertrophy in rats with MI. Combined inhibition of NHE-1 and ACE had even a more pronounced effect on PRSW (72±5 mmHg) and EDPVR (0.026±0.014 mmHg ,l,1), as well as cardiac hypertrophy that, however, did not reach statistical significance compared to cariporide treatment alone. The NHE-1 inhibitor cariporide significantly improved LV remodeling and function in rats with congestive heart failure induced by MI. The effect of cariporide was comparable or tended to be stronger (e.g. systolic function) compared to ramipril. Combined treatment with cariporide and ramipril tended to be more effective on LV remodeling in rats with heart failure than the single treatments. Thus, inhibition of the NHE-1 may be a promising novel therapeutic approach for the treatment of congestive heart failure. British Journal of Pharmacology (2005) 146, 723,731. doi:10.1038/sj.bjp.0706381 [source]


Sonic hedgehog derived from human pancreatic cancer cells augments angiogenic function of endothelial progenitor cells

CANCER SCIENCE, Issue 6 2008
Madoka Yamazaki
Hedgehog signaling is important in the pathogenesis of pancreatic cancer. Several recent observations suggest the involvement of sonic hedgehog (SHH) in postnatal neovascularization. We identified a novel role for SHH in tumor-associated angiogenesis in pancreatic cancer. Immunohistochemical analysis revealed that patched homolog 1 (PTCH1), both a receptor for and transcriptional target of hedgehog signaling, was expressed in a small fraction of endothelial cells within pancreatic cancer, but not in normal pancreatic tissue. When endothelial progenitor cells (EPC) isolated from human peripheral blood were cultured with supernatant from SHH-transfected 293 cells or pancreatic cancer cells, mRNA levels of vascular endothelial growth factor (VEGF), stromal cell-derived factor-1 and angiopoietin-1 were significantly increased, whereas no such induction was observed in human umbilical vein endothelial cell (HUVEC) and human dermal microvascular endothelial cell (HMVEC). HUVEC tube formation was stimulated when cocultured with EPC, and preconditioning EPC with supernatant from KP-1 N pancreatic cancer cells highly expressing SHH significantly enhanced the effect. The effect was partially attenuated by specific inhibition of SHH with cyclopamine or a neutralizing antibody. These findings suggest that tumor-derived SHH can induce angiogenesis, and this is mediated by its effects on EPC specifically. Targeting SHH would be a novel therapeutic approach that can inhibit not only proliferation of cancer cells but also EPC-mediated angiogenesis. (Cancer Sci 2008; 99: 1131,1138) [source]


Mechanisms of Epileptogenesis in Tuberous Sclerosis Complex and Related Malformations of Cortical Development with Abnormal Glioneuronal Proliferation

EPILEPSIA, Issue 1 2008
Michael Wong
Summary Malformations of cortical development (MCDs) are increasingly recognized as causes of medically intractable epilepsy. In order to develop more effective, rational therapies for refractory epilepsy related to MCDs, it is important to achieve a better understanding of the underlying mechanisms of epileptogenesis, but this is complicated by the wide variety of different radiographic, histopathological, and molecular features of these disorders. A subset of MCDs share a number of characteristic cellular and molecular abnormalities due to early defects in neuronal and glial proliferation and differentiation and have a particularly high incidence of epilepsy, suggesting that this category of MCDs with abnormal glioneuronal proliferation may also share a common set of primary mechanisms of epileptogenesis. This review critically analyzes both clinical and basic science evidence for overlapping mechanisms of epileptogenesis in this group of disorders, focusing on tuberous sclerosis complex, focal cortical dysplasia with balloon cells, and gangliogliomas. Specifically, the role of lesional versus perilesional regions, circuit versus cellular/molecular defects, and nonneuronal factors, such as astrocytes, in contributing to epileptogenesis in these MCDs is examined. An improved understanding of these various factors involved in epileptogenesis has direct clinical implications for optimizing current treatments or developing novel therapeutic approaches for epilepsy in these disorders. [source]


How best to fight that nasty itch , from new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus to novel therapeutic approaches

EXPERIMENTAL DERMATOLOGY, Issue 3 2005
T. Biró
While the enormous clinical and psychosocial importance of pruritus in many areas of medicine and the detrimental effects of chronic ,itch' on the quality of life of an affected individual are widely appreciated, the complexity of this sensation is still often grossly underestimated. The current Controversies feature highlights this complexity by portraying pruritus as a truly interdisciplinary problem at the crossroads of neurophysiology, neuroimmunology, neuropharmacology, protease research, internal medicine, and dermatology, which is combated most successfully if one keeps the multilayered nature of ,itch' in mind and adopts a holistic treatment approach , beyond the customary, frequently frustrane monotherapy with histamine receptor antagonists. In view of the often unsatisfactory, unidimensional, and altogether rather crude standard instruments for pruritus management that we still tend to use in clinical practice today, an interdisciplinary team of pruritus experts here critically examines recent progress in pruritus research that future itch management must take into consideration. Focusing on new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus, and discussing available neuropharmacological tools, specific research avenues are highlighted, whose pursuit promises to lead to novel, and hopefully more effective, forms of pruritus management. [source]


Desmoglein-3 is a target autoantigen in spontaneous canine pemphigus vulgaris

EXPERIMENTAL DERMATOLOGY, Issue 2 2003
Thierry Olivry
Abstract: Pemphigus vulgaris (PV) is an autoimmune blistering skin disease of humans and companion animals. In human patients, PV is associated with the production of IgG autoantibodies specific for keratinocyte desmosomal glycoproteins of the cadherin family. The purpose of this study was to determine whether antikeratinocyte IgG autoantibodies were present in the skin and serum of dogs with PV, and also to identify the canine PV autoantigen(s) targeted by circulating autoantibodies. Eleven dogs were selected because of the microscopic demonstration of suprabasal epithelial acantholysis. Direct immunofluorescence revealed the presence of IgG autoantibodies bound to the membrane of keratinocytes in skin biopsy specimens of 8/9 dogs (89%). Using indirect immunofluorescence, serum-circulating IgG autoantibodies were found in 10/11 (91%) and 5/11 (45%) dogs, using normal canine gingiva and cultured canine oral keratinocytes, respectively. By immunoblotting using cultured canine oral keratinocyte protein lysates, IgG autoantibodies from 7/9 (78%) tested dogs recognized a 130-kDa antigen that comigrated with that identified by rabbit polyclonal antibodies raised against desmoglein-3. This 130 kDa antigen was confirmed to represent the canine equivalent of human desmoglein-3 by immunoprecipitation-immunoblotting. The results of these studies provide evidence that the canine desmoglein-3 homologue is a major autoantigen in dogs with PV. These observations further establish spontaneous canine PV as a natural model for research on pathogenesis, etiology and novel therapeutic approaches for this disease of humans. [source]


Decay-accelerating factor induction by tumour necrosis factor-,, through a phosphatidylinositol-3 kinase and protein kinase C-dependent pathway, protects murine vascular endothelial cells against complement deposition

IMMUNOLOGY, Issue 2 2003
Saifur R. Ahmad
Summary We have shown that human endothelial cells (EC) are protected against complement-mediated injury by the inducible expression of decay-accelerating factor (DAF). To understand further the importance of DAF regulation, we characterized EC DAF expression on murine EC in vitro and in vivo using a model of glomerulonephritis. Flow cytometry using the monoclonal antibody (mAb) Riko-3 [binds transmembrane- and glycosylphosphatidylinositol (GPI)-anchored DAF], mAb Riko-4 (binds GPI-anchored DAF) and reverse transcription,polymerase chain reaction (RT,PCR), demonstrated that murine EC DAF is GPI-anchored. Tumour necrosis factor-, (TNF-,) increased EC DAF expression, detectable at 6 hr and maximal at 24,48 hr poststimulation. DAF upregulation required increased steady-state DAF mRNA and protein synthesis. In contrast, no increased expression of the murine complement receptor-related protein-Y (Crry) was seen with TNF-,. DAF upregulation was mediated via a protein kinase C (PKC),, phosphoinositide-3 kinase (PI-3 kinase), p38 mitogen-activated protein kinase (MAPK) and nuclear factor-,B (NF-,B)-dependent pathway. The increased DAF was functionally relevant, resulting in a marked reduction in C3 deposition following complement activation. In a nephrotoxic nephritis model, DAF expression on glomerular capillaries was significantly increased 2 hr after the induction of disease. The demonstration of DAF upregulation above constitutive levels suggests that this may be important in the maintenance of vascular integrity during inflammation, when the risk of complement-mediated injury is increased. The mouse represents a suitable model for the study of novel therapeutic approaches by which vascular endothelium may be conditioned against complement-mediated injury. [source]


The current status of targeted therapy for non-small cell lung cancer

INTERNAL MEDICINE JOURNAL, Issue 9 2010
H. Francis
Abstract Lung cancer accounts for more cancer-related deaths than any other malignancy in Australia and worldwide. Non-small cell lung cancer (NSCLC) accounts for about 85% of lung cancers and is associated with a 5-year survival of only 15%. Treatment with platinum-based doublets in the first-line setting and single agent chemotherapy in the second-line setting has improved survival and quality of life in patients with NSCLC. However, the benefits associated with chemotherapy are modest and serve to stress the need for novel therapeutic approaches. In the last decade a range of targeted therapies has been evaluated in NSCLC. Dramatic and often durable responses were seen in patients treated with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) gefitinib and erlotinib particularly in females, non-smokers, patients of East Asian ethnicity and those with adenocarcinomas , a group subsequently found to be enriched for tumours with activating EGFR mutations. Large randomized phase III trials have since established a role for EGFR TKI in the second- and third-line setting as well as a potential role for the monoclonal antibodies bevacizumab and cetuximab, directed at vascular endothelial growth factor and EGFR, respectively, in the combination with chemotherapy in the first-line setting. Recently it has been shown that patients with EGFR mutations may benefit from gefitinib in the first-line setting. Other promising agents under evaluation are inhibitors of the insulin-like growth factor-1 receptor and inhibitors of recently described ALK gene rearrangements. [source]


KIT and RAS signalling pathways in testicular germ cell tumours: new data and a review of the literature

INTERNATIONAL JOURNAL OF ANDROLOGY, Issue 4 2007
N. C. Goddard
Summary Testicular germ cell tumours (TGCTs) are the leading cause of cancer deaths in young male Caucasians. Identifying changes in DNA copy number can pinpoint genes involved in tumour development. We defined the smallest overlapping regions of imbalance in TGCTs using array comparative genomic hybridization analysis. Novel regions, or regions which refined those previously reported, were identified. The expression profile of genes from 12p, which is invariably gained in TGCTs, and amplicons defined at 12p11.2-12.1 and 4q12, suggest KRAS and KIT involvement in TGCT and seminoma development, respectively. Amplification of these genes was not found in intratubular germ cell neoplasia adjacent to invasive disease showing these changes, suggesting their involvement in tumour progression. Activating mutations of RAS genes (KRAS or NRAS) and overexpression of KRAS were mutually exclusive events. These, correlations between the expression levels of KIT, KRAS and GRB7 (which encodes an adapter molecule known to interact with the KIT tyrosine kinase receptor) and other reported evidence reviewed here, are consistent with a role for activation of KIT and RAS signalling in TGCT development. In order to assess a role for KIT in seminomas, we modulated the level of KIT expression in TCam-2, a seminoma cell line. The likely seminomatous origin of this cell line was supported by demonstrating KIT and OCT3/4 overexpression and gain of 12p material. Reducing the expression of KIT in TCam-2 through RNA inhibition resulted in decreased cell viability. Further understanding of KIT and RAS signalling in TGCTs may lead to novel therapeutic approaches for these tumours. [source]


Novel neuroprotective, neuritogenic and anti-amyloidogenic properties of 2,4-dinitrophenol: The gentle face of Janus

IUBMB LIFE, Issue 4 2006
Fernanda G. De Felice
Abstract In Roman mythology, Janus was the god of gates, doors, beginnings and endings. He was usually depicted with two faces looking in opposite directions. Janus was frequently used to symbolize change and transitions, such as the progression from past to future or from one viewpoint to another. 2,4-dinitrophenol (DNP) and other nitrophenols have long been known to be toxic at high concentrations (the 'bad' face of DNP), an effect that appears essentially related to interference with cellular energy metabolism due to uncoupling of mitochondrial oxidative phosphorylation. Five years ago, however, we published the first report showing that low concentrations of DNP protect neurons against the toxicity of the amyloid-, peptide (De Felice et al. (2001) FASEB J. 15:1297 - 1299]. Since then, other studies have provided evidence of beneficial actions of DNP (at low concentrations), including neuroprotection against different types of insult, blockade of amyloid aggregation, stimulation of neurite outgrowth and neuronal differentiation, and even extension of lifespan in certain organisms. Some of these effects appear to be due to mild mitochondrial uncoupling and prevention of cellular oxidative stress, whereas other actions are related to activation of additional intracellular signaling pathways. Thus, a novel and 'gentle' face of DNP is emerging from such studies. In this review, we discuss both toxic and beneficial actions of DNP. The evidence available so far suggests that DNP and other compounds with similar biological activities may be of significant interest to the development of novel therapeutic approaches for neurodegenerative diseases and other neurological disorders. iubmb Life, 58: 185-191, 2006 [source]


Regenerative medicine in the treatment of peripheral arterial disease

JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 4 2009
Erica B. Sneider
Abstract The last decade has witnessed a dramatic increase in the mechanistic understanding of angiogenesis and arteriogenesis, the two processes by which the body responds to obstruction of large conduit arteries. This knowledge has been translated into novel therapeutic approaches to the treatment of peripheral arterial disease, a condition characterized by progressive narrowing of lower extremity arteries and heretofore solely amenable to surgical revascularization. Clinical trials of molecular, genetic, and cell-based treatments for peripheral artery obstruction have generally provided encouraging results. J. Cell. Biochem. 108: 753,761, 2009. © 2009 Wiley-Liss, Inc. [source]


Chemokines in pathology and medicine

JOURNAL OF INTERNAL MEDICINE, Issue 2 2001
M. Baggiolini
Abstract. Baggiolini M (Theodor Kocher Institute, University of Bern, and Institute for Research in Biomedicine, Bellinzona, Switzerland). Chemokines in pathology and medicine (Review). J Intern Med 2001; 250: 91,104. About 50 human chemokines and nearly 20 receptors have been identified and characterized in little more than a decade since the discovery of interleukin 8 (IL-8), the first chemotactic cytokine. Research in this field has dramatically changed our understanding of leucocyte traffic in inflammation and immunity. This paper has been written for scientists and practitioners in the field of medicine. It reviews in concise and intelligible form information that I consider useful for understanding the role of chemokines in human pathophysiology. The main areas covered are: (i) the basics of chemokine structures, mode of action, activities and selectivity; (ii) newer aspects of the broad involvement of chemokines in the regulation of immune defence and the housekeeping of the immune system; (iii) the role of chemokines in pathology as illustrated by animal models and studies of human diseases; and (iv) novel therapeutic approaches for a variety of inflammatory conditions, which are based on modulation of chemokine activity. [source]


Vascular and dendritic cell coagulation signaling in sepsis progression

JOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 2009
W. RUF
Summary., The intrinsic signaling networks of the coagulation pathways have recently emerged as crucial determinants for survival in sepsis and systemic inflammatory response syndromes. Protease activated receptor (PAR) 1 is central to both lethality promoting and vascular protective signaling. In the vascular anticoagulant pathway, EPCR/aPC-PAR1 signaling prevents vascular leakage and genetic or acute deficiencies in this pathway promote lethality. In addition, coagulation signaling acts directly on cells of the innate immune system. Dendritic cell (DC) thrombin-PAR1 signaling is coupled to the migration promoting sphingosine 1 phosphate receptor 3 (S1P3). Thrombin generated in the lymphatic compartment perturbs DCs to promote systemic inflammation and disseminated intravascular coagulation in severe sepsis. Signaling-selective aPC variants and selective modulators of the S1P receptor system attenuate sepsis lethality, suggesting novel therapeutic approaches that can be employed to rebalance alterations in the coagulation signaling pathways in severe inflammatory disorders. [source]


An updated view of hemostasis: mechanisms of hemostatic dysfuntion associated with sepsis

JOURNAL OF VETERINARY EMERGENCY AND CRITICAL CARE, Issue 2 2005
DACVECC, Kate Hopper BVSc
Abstract Objective: To review the current understanding of mechanisms involved in normal hemostasis and to describe the changes associated with pro-inflammatory disease processes such as sepsis. Data sources: Original research articles and scientific reviews. Human data synthesis: Organ damage caused by sepsis is created in part by the interdependent relationship between hemostasis and inflammation. Markers of coagulation have been found to have prognostic value in human patients with sepsis and there are both experimental and clinical investigations of the therapeutic potential of modulating the hemostatic system in sepsis. Improvement of 28-day all-cause mortality in severe sepsis by treatment with recombinant human activated Protein C strongly supports the interdependence of hemostasis and inflammation in the pathophysiology of sepsis. Veterinary data synthesis: Publications reporting clinical evaluation of the hemostatic changes occurring in septic dogs or cats are minimal. Experimental animal models of sepsis reveal significant similarity between human and animal sepsis and may provide relevance to clinical veterinary medicine until prospective clinical evaluations are published. Conclusions: It is now apparent that inflammation and the coagulation system are intimately connected. Understanding this relationship provides some insight into the pathogenesis of the hemostatic changes associated with sepsis. This new updated view of hemostasis may lead to the development of novel therapeutic approaches to sepsis and disseminated intravascular coagulation in veterinary medicine. [source]