Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 349
Filter
1.
Lancet Neurol ; 21(6): 508, 2022 06.
Article in English | MEDLINE | ID: mdl-35568045
2.
J Assist Reprod Genet ; 37(8): 1975-1997, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32592074

ABSTRACT

RESEARCH QUESTION: To investigate whether patient factors influence the decision to freeze a blastocyst with low implantation potential. DESIGN: This experimental study assessed 170 practicing embryologists from a variety of countries who were recruited via an online survey. Participants were currently practicing embryologists, who grade blastocysts as part of this role. The survey presented decision-making 'vignettes' to participants. These included specific patient information, as well as an image of an expanded blastocyst that was of borderline quality for inner cell mass and trophectoderm, for which the embryologist selected whether or not to freeze. High/low maternal age, the presence/absence of other top quality blastocysts, and the presence/absence of previously unsuccessful IVF cycles were systematically varied within the patient information in a 2 × 2 × 2 design. Participants reported how likely they would be to freeze a particular blastocyst on a scale of 1 (Extremely Unlikely) to 7 (Extremely Likely), and whether or not they would ultimately freeze each blastocyst (Yes or No). RESULTS: Lower maternal age, no other high-quality blastocysts within the cohort, and multiple unsuccessful IVF cycles were associated with greater likelihood of recommending to freeze (P < .001). Furthermore, significant interactions among all three patient factors were noted. CONCLUSION: This study provides evidence suggesting that when faced with an uncertain blastocyst, factors pertaining to the patient (maternal age, the presence/absence of other top quality blastocysts, and the presence/absence of previously unsuccessful IVF cycles) influence the decision to freeze.


Subject(s)
Blastocyst/physiology , Embryo Culture Techniques , Embryo Implantation/physiology , Embryonic Development/genetics , Adult , Cohort Studies , Cryopreservation , Embryo Implantation/genetics , Embryo Transfer , Female , Freezing/adverse effects , Humans , Live Birth , Pregnancy
3.
J Eur Acad Dermatol Venereol ; 34(11): 2566-2573, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32364296

ABSTRACT

BACKGROUND: Anti-tumour necrosis factor (TNF) and anti-interleukin (IL)-12/23 biologics revolutionized plaque psoriasis treatment by enabling ≥75% improvement in the Psoriasis Area and Severity Index (PASI 75) in clinical trials. Modern biologics are now reported to achieve PASI 100 (complete skin clearance) in clinical trials. However, real-world evidence of skin clearance rates with biologics is limited. PSO-BIO-REAL was conducted to understand the real-world burden of plaque psoriasis. OBJECTIVE: The primary objective of this observational study was to estimate the proportion of patients who achieved complete skin clearance at 6 months. Secondary objectives included maintenance of response and evaluation of complete skin clearance at 12 months. METHODS: PSO-BIO-REAL was a multinational, prospective, real-world, non-interventional study of skin clearance and patient-reported outcomes (PROs) with biologics. A total of 846 patients from the United States (32%), France (28%), Italy (22%), the United Kingdom (11%) and Germany (8%) were enrolled and followed for one year. Eligible patients were aged ≥18 years with moderate-to-severe plaque psoriasis who had initiated a biologic for plaque psoriasis. Patients could be biologic-naïve or switching biologics (biologic-experienced). Assessments were made at baseline and at months 6 and 12. RESULTS: At 6 and 12 months, 23% and 26% of patients achieved complete skin clearance, respectively. Prior to study entry, 60% were biologic-naïve. The proportion of patients achieving complete skin clearance was lower among biologic-experienced patients (20% at both months 6 and 12) compared with biologic-naïve patients (25% at month 6, 30% at month 12). The rate of complete skin clearance decreased as the number of prior biologics and baseline comorbidities increased. CONCLUSION: Only one in four patients achieved complete skin clearance after 6 months of treatment with biologics. The study indicates there still is an unmet need for more efficacious biologics for patients with psoriasis.


Subject(s)
Biological Products , Psoriasis , Adolescent , Adult , Biological Products/therapeutic use , France , Germany , Humans , Italy , Prospective Studies , Psoriasis/drug therapy , United Kingdom
4.
Med Phys ; 2018 Jun 21.
Article in English | MEDLINE | ID: mdl-29926932

ABSTRACT

PURPOSE: Quantitative computed tomography (QCT)-derived measures of lung density are valued methods for objectively characterizing lung parenchymal and peripheral airways disease and are being used in a growing number of lung disease focused trials. Detector and reconstruction improvements in CT technology have allowed for significant radiation dose reduction in image acquisition with comparable qualitative image quality. We report the impact of detector type and reconstruction type on QCT lung density measures in relation to decreasing dose indices. METHODS: Two sets of studies were completed in an in vivo pig model with a SOMATOM Definition Flash CT system: (a) prior to system upgrade with conventional detectors (UFC) and filtered back projection (FBP), and (b) post system upgrade with integrated electronic detectors (STELLAR) and iterative reconstruction (SAFIRE). CT data were acquired across estimated CT volume dose indices (CTDIvol ) ranging from 0.75 to 15 mGy at both inspiratory and expiratory breath holds. Semiautomated lung segmentations allowed calculation of histogram median, kurtosis, and 15th percentile. Percentage of voxels below -910 HU and -950 HU (inspiratory), and -856 HU (expiratory) were also examined. The changes in these QCT metrics from dose reduction (15 mGy down to 0.75 mGy) were calculated relative to paired reference values (15 mGy). Results were compared based on detector and reconstruction type. RESULTS: In this study, STELLAR detectors improved concordance with 15 mGy values down to 3 mGy for inspiratory scans and 6 mGy for expiratory scans. The addition of SAFIRE reconstruction in all acquired measurements resulted in minimal deviation from reference values at 0.75 mGy. CONCLUSION: The use of STELLAR integrated electronic detectors and SAFIRE iterative reconstruction may allow for comparable lung density measures with CT dose indices down to 0.75 mGy.

5.
Epidemiol Psychiatr Sci ; 27(1): 94-102, 2018 02.
Article in English | MEDLINE | ID: mdl-27852333

ABSTRACT

AIMS: To characterise and identify nationwide trends in suicide-related emergency department (ED) visits in the USA from 2006 to 2013. METHODS: We used data from the Nationwide Emergency Department Sample (NEDS) from 2006 to 2013. E-codes were used to identify ED visits related to suicide attempts and self-inflicted injury. Visits were characterised by factors such as age, sex, US census region, calendar month, as well as injury severity and mechanism. Injury severity and mechanism were compared between age groups and sex by chi-square tests and Wilcoxon rank-sum tests. Population-based rates were computed using US Census data. RESULTS: Between 2006 and 2013, a total of 3 567 084 suicide attempt-related ED visits were reported. The total number of visits was stable between 2006 and 2013, with a population-based rate ranging from 163.1 to 173.8 per 100 000 annually. The frequency of these visits peaks during ages 15-19 and plateaus during ages 35-45, with a mean age at presentation of 33.2 years. More visits were by females (57.4%) than by males (42.6%); however, the age patterns for males and females were similar. Visits peaked in late spring (8.9% of all visits occurred in May), with a smaller peak in the fall. The most common mechanism of injury was poisoning (66.5%), followed by cutting and piercing (22.1%). Males were 1.6 times more likely than females to use violent methods to attempt suicide (OR = 1.64; 95% CI = 1.60-1.68; p < 0.001). The vast majority of patients (82.7%) had a concurrent mental disorder. Mood disorders were the most common (42.1%), followed by substance-related disorders (12.1%), alcohol-related disorders (8.9%) and anxiety disorders (6.4%). CONCLUSIONS: The annual incidence of ED visits for attempted suicide and self-inflicted injury in the NEDS is comparable with figures previously reported from other national databases. We highlighted the value of the NEDS in allowing us to look in depth at age, sex, seasonal and mechanism patterns. Furthermore, using this large national database, we confirmed results from previous smaller studies, including a higher incidence of suicide attempts among women and individuals aged 15-19 years, a large seasonal peak in suicide attempts in the spring, a predominance of poisoning as the mechanism of injury for suicide attempts and a greater use of violent mechanisms in men, suggesting possible avenues for further research into strategies for prevention.


Subject(s)
Emergency Service, Hospital/statistics & numerical data , Hospitalization/statistics & numerical data , Self Mutilation/epidemiology , Self-Injurious Behavior/epidemiology , Suicide, Attempted/statistics & numerical data , Adolescent , Adult , Age Distribution , Female , Humans , Incidence , Male , Middle Aged , Poisoning/epidemiology , Sex Distribution , United States/epidemiology , Young Adult
6.
Oncogene ; 35(6): 793-9, 2016 Feb 11.
Article in English | MEDLINE | ID: mdl-25961932

ABSTRACT

Regions of hypoxia occur in most solid tumors, and they are associated with a poor prognostic outcome. Despite the absence of detectable DNA damage, severe hypoxia (<0.1% O2) induces a DNA damage response, including the activation of p53 and subsequent induction of p53-dependent apoptosis. Factors affecting hypoxia-induced p53-dependent apoptosis are unclear. Here we asked whether H3K9me3, through mediating gene repression, could regulate hypoxia-induced p53-dependent apoptosis. Under hypoxic conditions, increases in H3K9me3 occur in an oxygen-dependent but HIF-1-independent manner. We demonstrate that under hypoxic conditions, which induce p53 activity, the negative regulator of p53, APAK, is repressed by increases in H3K9me3 along the APAK loci. APAK repression in hypoxia is mediated by the methyltransferase SETDB1 but not Suv39h1 or G9a. Interestingly, increasing hypoxia-induced H3K9me3 through pharmacological inhibition of JMJD2 family members leads to an increase in apoptosis and decreased clonogenic survival and again correlates with APAK expression. The relevance of understanding the mechanisms of APAK expression regulation to human disease was suggested by analysis of patients with colorectal cancer, which demonstrates that high APAK expression correlates with poor prognosis. Together, these data demonstrate the functional importance of H3K9me3 in hypoxia, and they provide a novel mechanistic link between H3K9me3, p53 and apoptosis in physiologically relevant conditions of hypoxia.


Subject(s)
Apoptosis Regulatory Proteins/genetics , Apoptosis/genetics , DNA-Binding Proteins/genetics , Histone-Lysine N-Methyltransferase/metabolism , Histones/metabolism , Histones/physiology , Tumor Suppressor Protein p53/physiology , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Cell Hypoxia/genetics , DNA-Binding Proteins/metabolism , Gene Expression Regulation, Neoplastic/drug effects , Gene Knockdown Techniques , HCT116 Cells , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Oxygen/pharmacology , Tumor Cells, Cultured
7.
Br J Radiol ; 88(1047): 20140649, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25513745

ABSTRACT

Chromatin, the structure formed by the wrapping of approximately 146 base pairs of DNA around an octamer of histones, has a profound impact on numerous DNA-based processes. Chromatin modifications and chromatin remodellers have recently been implicated in important aspects of the DNA damage response including facilitating the initial sensing of the damage as well as subsequent recruitment of repair factors. Radiation is an effective cancer therapy for a large number of tumours, and there is considerable interest in finding approaches that might further increase the efficacy of radiotherapy. The use of radiation leads to the generation of DNA damage and, therefore, agents that can affect the sensing and repair of DNA damage may have an impact on overall radiation efficacy. The chromatin modifications as well as chromatin modifiers that have been associated with the DNA damage response will be summarized in this review. An emphasis will be placed on those processes that can be pharmacologically manipulated with currently available inhibitors. The rationale for the use of these inhibitors in combination with radiation will also be described.


Subject(s)
Chromatin/chemistry , DNA Damage/radiation effects , DNA Repair/radiation effects , DNA, Neoplasm/radiation effects , Neoplasms/radiotherapy , DNA, Neoplasm/genetics , Genomic Instability , Histones/metabolism , Humans , Molecular Structure , Neoplasms/genetics , Neoplasms/metabolism , Radiation, Ionizing
8.
Oncogene ; 34(36): 4758-66, 2015 Sep 03.
Article in English | MEDLINE | ID: mdl-25531325

ABSTRACT

Cancer cells gain a growth advantage through the so-called Warburg effect by shifting glucose metabolism from oxidative phosphorylation to aerobic glycolysis. Hypoxia-inducible factor 1 (HIF-1) has been suggested to function in metabolic reprogramming; however, the underlying mechanism has not been fully elucidated. We found that the aberrant expression of wild-type isocitrate dehydrogenase 3α (IDH3α), a subunit of the IDH3 heterotetramer, decreased α-ketoglutarate levels and increased the stability and transactivation activity of HIF-1α in cancer cells. The silencing of IDH3α significantly delayed tumor growth by suppressing the HIF-1-mediated Warburg effect and angiogenesis. IDH3α expression was associated with the poor postoperative overall survival of lung and breast cancer patients. These results justify the exploitation of IDH3 as a novel target for the diagnosis and treatment of cancers.


Subject(s)
Breast Neoplasms/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Isocitrate Dehydrogenase/biosynthesis , Lung Neoplasms/genetics , Neovascularization, Pathologic/genetics , Animals , Breast Neoplasms/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Glucose/metabolism , Glycolysis , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Isocitrate Dehydrogenase/antagonists & inhibitors , Isocitrate Dehydrogenase/genetics , Lung Neoplasms/pathology , Mice , Neovascularization, Pathologic/pathology , Oxidative Phosphorylation
9.
Clin Oncol (R Coll Radiol) ; 26(5): 277-88, 2014 May.
Article in English | MEDLINE | ID: mdl-24602562

ABSTRACT

Hypoxia was identified as a microenvironmental component of solid tumours over 60 years ago and was immediately recognised as a potential barrier to therapy through the reliance of radiotherapy on oxygen to elicit maximal cytotoxicity. Over the last two decades both clinical and experimental studies have markedly enhanced our understanding of how hypoxia influences cellular behaviour and therapy response. Furthermore, they have confirmed early assumptions that low oxygenation status in tumours is an exploitable target in cancer therapy. Generally such approaches will be more beneficial to patients with hypoxic tumours, necessitating the use of biomarkers that reflect oxygenation status. Tissue biomarkers have shown utility in many studies. Further significant advances have been made in the non-invasive measurement of tumour hypoxia with positron emission tomography, magnetic resonance imaging and other imaging modalities. Here, we describe the complexities of defining and measuring tumour hypoxia and highlight the therapeutic approaches to combat it.


Subject(s)
Drug Resistance, Neoplasm , Neoplasms/metabolism , Neoplasms/therapy , Oxygen/metabolism , Animals , Antineoplastic Agents/pharmacology , Cell Hypoxia , DNA Repair/drug effects , DNA Repair/physiology , Humans , Hypoxia-Inducible Factor 1/metabolism , Magnetic Resonance Imaging/methods , Neoplasms/diagnosis , Positron-Emission Tomography , Prodrugs/pharmacology , Signal Transduction/physiology
11.
Cell Death Dis ; 3: e441, 2012 Dec 06.
Article in English | MEDLINE | ID: mdl-23222511

ABSTRACT

Combined radiochemotherapy is the currently used therapy for locally advanced pancreatic ductal adenocarcinoma (PDAC), but normal tissue toxicity limits its application. Here we test the hypothesis that inhibition of ATR (ATM-Rad3-related) could increase the sensitivity of the cancer cells to radiation or chemotherapy without affecting normal cells. We tested VE-822, an ATR inhibitor, for in vitro and in vivo radiosensitization. Chk1 phosphorylation was used to indicate ATR activity, γH2AX and 53BP1 foci as evidence of DNA damage and Rad51 foci for homologous recombination activity. Sensitivity to radiation (XRT) and gemcitabine was measured with clonogenic assays in vitro and tumor growth delay in vivo. Murine intestinal damage was evaluated after abdominal XRT. VE-822 inhibited ATR in vitro and in vivo. VE-822 decreased maintenance of cell-cycle checkpoints, increased persistent DNA damage and decreased homologous recombination in irradiated cancer cells. VE-822 decreased survival of pancreatic cancer cells but not normal cells in response to XRT or gemcitabine. VE-822 markedly prolonged growth delay of pancreatic cancer xenografts after XRT and gemcitabine-based chemoradiation without augmenting normal cell or tissue toxicity. These findings support ATR inhibition as a promising new approach to improve the therapeutic ration of radiochemotherapy for patients with PDAC.


Subject(s)
Cell Cycle Proteins/antagonists & inhibitors , Isoxazoles/administration & dosage , Pancreatic Neoplasms/radiotherapy , Protein Kinase Inhibitors/administration & dosage , Protein Serine-Threonine Kinases/antagonists & inhibitors , Pyrazines/administration & dosage , Radiation-Sensitizing Agents/administration & dosage , Animals , Ataxia Telangiectasia Mutated Proteins , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/radiation effects , Checkpoint Kinase 1 , DNA Damage/drug effects , DNA Damage/radiation effects , Female , Humans , Mice , Mice, Inbred BALB C , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/metabolism , Phosphorylation/drug effects , Phosphorylation/radiation effects , Protein Kinases/genetics , Protein Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Radiation Tolerance
12.
Br J Cancer ; 107(2): 291-9, 2012 Jul 10.
Article in English | MEDLINE | ID: mdl-22713662

ABSTRACT

BACKGROUND: Most solid tumours contain regions of sub-optimal oxygen concentration (hypoxia). Hypoxic cancer cells are more resistant to radiotherapy and represent the most aggressive fraction of a tumour. It is therefore essential that strategies continue to be developed to target hypoxic cancer cells. Inhibition of the DNA damage response (DDR) might be an effective way of sensitising hypoxic tumour cells to radiotherapy. METHODS: Here, we describe the cellular effects of pharmacological inhibition of the apical DDR kinase ATR (Ataxia Telangiectasia and Rad 3 related) with a highly selective inhibitor, VE-821, in hypoxic conditions and its potential as a radiosensitiser. RESULTS: VE-821 was shown to inhibit ATR-mediated signalling in response to replication arrest induced by severe hypoxia. In these same conditions, VE-821 induced DNA damage and consequently increased Ataxia Telangiectasia Mutated-mediated phosphorylation of H2AX and KAP1. Consistently, ATR inhibition sensitised tumour cell lines to a range of oxygen tensions. Most importantly, VE-821 increased radiation-induced loss of viability in hypoxic conditions. Using this inhibitor we have also demonstrated for the first time a link between ATR and the key regulator of the hypoxic response, HIF-1. HIF-1 stabilisation and transcriptional activity were both decreased in response to ATR inhibition. CONCLUSION: These findings suggest that ATR inhibition represents a novel strategy to target tumour cells in conditions relevant to pathophysiology and enhance the efficacy of radiotherapy.


Subject(s)
Cell Cycle Proteins/antagonists & inhibitors , Cell Hypoxia/drug effects , Protein Serine-Threonine Kinases/antagonists & inhibitors , Radiation Tolerance/drug effects , Ataxia Telangiectasia/genetics , Ataxia Telangiectasia Mutated Proteins , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/genetics , DNA Damage , DNA Replication/drug effects , HCT116 Cells , HeLa Cells , Histones/genetics , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/antagonists & inhibitors , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Phosphorylation/drug effects , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Pyrazines/pharmacology , Radiation Tolerance/genetics , Radiotherapy/methods , Repressor Proteins/genetics , Signal Transduction/drug effects , Sulfones/pharmacology , Tripartite Motif-Containing Protein 28
13.
Clin Endocrinol (Oxf) ; 76(2): 201-6, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21682759

ABSTRACT

OBJECTIVE: Vitamin D deficiency (VDD) is prevalent in HIV, and following antiretroviral therapy (ART), increased rates of lipoatrophy and metabolic abnormalities are described. We investigated the relationships between 25-hydroxyvitamin D [25(OH)D] and other metabolic parameters in a group of HIV patients with and without lipoatrophy to examine whether lipoatrophy could explain the high prevalence of VDD and metabolic abnormalities. BACKGROUND: Vitamin D receptors are expressed in adipose tissue implicating vitamin D, through paracrine/autocrine mechanism, in exerting effects on fat metabolism. HIV patients frequently suffer from VDD, and those treated with thymidine analogues frequently suffer from lipoatrophy so we investigated whether lipoatrophy could explain these associations. DESIGN AND PATIENTS: Cross-sectional study of HIV-infected male patients (n = 107; 39 with lipoatrophy) from the West Australian cohort with measurements of 25(OH)D, adiponectin, insulin, lipids and leg fat as a percentage of mass. RESULTS: Reduced 25(OH)D levels were common and significantly associated with higher serum insulin in the entire cohort (P = 0·006), but there was no difference in 25(OH)D between untreated and antiretroviral-treated patients with or without lipoatrophy. Treated patients with lipoatrophy were more likely to take thymidine analogue therapy, were older and on therapy longer than treated patients without lipoatrophy. Adiponectin levels did not correlate with 25(OH)D, but lipoatrophic-treated patients had lower levels of adiponectin compared with nonlipoatrophic-treated patients. CONCLUSIONS: Lower 25(OH)D is associated with higher serum insulin but not lipoatrophy or hypoadiponectinemia in HIV-infected patients. The association between VDD and insulin resistance is likely to be mediated by independent mechanisms.


Subject(s)
Anti-HIV Agents/adverse effects , HIV Infections/drug therapy , Insulin/blood , Lipodystrophy/blood , Vitamin D/analogs & derivatives , Adult , Cross-Sectional Studies , HIV Infections/blood , HIV Infections/complications , Humans , Lipodystrophy/etiology , Male , Middle Aged , Vitamin D/blood
14.
Oncogene ; 30(48): 4835-42, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21625218

ABSTRACT

Junction-mediating and regulatory protein (JMY) is a novel p53 cofactor that regulates p53 activity during stress. JMY interacts with p300/CBP, which are ubiquitous transcriptional co-activators that interact with a variety of sequence-specific transcription factors, including hypoxia-inducible factor-1α (HIF-1α). In addition, JMY is an actin-nucleating protein, which, through its WH2 domains, stimulates cell motility. In this study, we show that JMY is upregulated during hypoxia in a HIF-1α-dependent manner. The JMY gene contains HIF-responsive elements in its promoter region and HIF-1α is recruited to its promoter during hypoxia. HIF-1α drives transcription of JMY, which accounts for its induction under hypoxia. Moreover, the enhanced cell motility and invasion that occurs during hypoxia requires JMY, as depleting JMY under hypoxic conditions causes decreased cell motility. Our results establish the interplay between JMY and HIF-1α as a new mechanism that controls cell motility under hypoxic stress.


Subject(s)
Cell Hypoxia , Hypoxia-Inducible Factor 1, alpha Subunit/physiology , Nuclear Proteins/physiology , Trans-Activators/physiology , Base Sequence , Humans , Molecular Sequence Data , Nuclear Proteins/genetics , Promoter Regions, Genetic , Trans-Activators/genetics
15.
Br J Cancer ; 104(4): 635-42, 2011 Feb 15.
Article in English | MEDLINE | ID: mdl-21285983

ABSTRACT

BACKGROUND: PG545 is a heparan sulfate (HS) mimetic that inhibits tumour angiogenesis by sequestering angiogenic growth factors in the extracellular matrix (ECM), thus limiting subsequent binding to receptors. Importantly, PG545 also inhibits heparanase, the only endoglycosidase which cleaves HS chains in the ECM. The aim of the study was to assess PG545 in various solid tumour and metastasis models. METHODS: The anti-angiogenic, anti-tumour and anti-metastatic properties of PG545 were assessed using in vivo angiogenesis, solid tumour and metastasis models. Pharmacokinetic (PK) data were also generated in tumour-bearing mice to gain an understanding of optimal dosing schedules and regimens. RESULTS: PG545 was shown to inhibit angiogenesis in vivo and induce anti-tumour or anti-metastatic effects in murine models of breast, prostate, liver, lung, colon, head and neck cancers and melanoma. Enhanced anti-tumour activity was also noted when used in combination with sorafenib in a liver cancer model. PK data revealed that the half-life of PG545 was relatively long, with pharmacologically relevant concentrations of radiolabeled PG545 observed in liver tumours. CONCLUSION: PG545 is a new anti-angiogenic clinical candidate for cancer therapy. The anti-metastatic property of PG545, likely due to the inhibition of heparanase, may prove to be a critical attribute as the compound enters phase I clinical trials.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Glucuronidase/therapeutic use , Neoplasms/drug therapy , Saponins/therapeutic use , Angiogenesis Inhibitors/pharmacology , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Glucuronidase/pharmacology , HT29 Cells , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Nude , Mice, SCID , Neoplasm Metastasis , Neoplasms/pathology , Neoplasms/prevention & control , Saponins/pharmacology , Treatment Outcome , Xenograft Model Antitumor Assays
16.
Transplant Proc ; 42(7): 2687-92, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20832570

ABSTRACT

BACKGROUND: Blood product transfusion has been successfully used in solid-organ transplantation to induce tolerance. Whether a similar protective effect of blood product transfusion exists in heart transplantation is controversial. OBJECTIVE: To investigate the effect of cellular blood product transfusion within 2 weeks posttransplantation on the incidence of cellular and antibody-mediated rejection. PATIENTS AND METHODS: Patients were grouped on the basis of number of blood transfusions; group 1 received no transfusions, and groups 2, 3, and 4 each received an incremental number of transfusion units. All endomyocardial biopsy samples were routinely studied using immunofluorescence in the first 12 weeks posttransplantation. RESULTS: Baseline characteristics including age, sex, body mass index, history of diabetes, donor characteristics, and pretransplantation laboratory values were similar except that group 4 had a higher rate of previous sternotomy and longer ischemic time during transplantation. Approximately 9200 endomyocardial biopsy samples composed the data. Short- and long-term freedom from the International Society for Heart & Lung Transplantation grade 3A or higher cellular rejection and from antibody-mediated rejection were comparable between groups. CONCLUSIONS: Blood transfusions within the first 2 weeks post-transplantation do not seem to confer any protective effect against posttransplantation cellular rejection or antibody- mediated rejection. Whether other unmeasured confounding factors mask their effect requires further prospective studies.


Subject(s)
Blood Component Transfusion/methods , Graft Rejection/prevention & control , Heart Transplantation/pathology , Immune Tolerance/drug effects , Adult , Biopsy , Female , Graft Rejection/epidemiology , Graft Rejection/immunology , Heart-Lung Transplantation/pathology , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Treatment Outcome
17.
Oncogene ; 29(31): 4424-35, 2010 Aug 05.
Article in English | MEDLINE | ID: mdl-20514020

ABSTRACT

Activating transcription factor 4 (ATF4) is a transcription factor induced under severe hypoxia and a component of the PERK pathway involved in the unfolded protein response (UPR), a process that protects cells from the negative consequences of endoplasmic reticulum (ER) stress. In this study, we have used small interfering RNA (siRNA) and microarray analysis to provide the first whole-genome analysis of genes regulated by ATF4 in cancer cells in response to severe and prolonged hypoxic stress. We show that ATF4 is required for ER stress and hypoxia-induced expansion of autophagy. MAP1LC3B (LC3B) is a key component of the autophagosomal membrane, and in this study we demonstrate that ATF4 facilitates autophagy through direct binding to a cyclic AMP response element binding site in the LC3B promoter, resulting in LC3B upregulation. Previously, we have shown that Bortezomib-induced ATF4 stabilization, which then upregulated LC3B expression and had a critical role in activating autophagy, protecting cells from Bortezomib-induced cell death. We also showed that severe hypoxia stabilizes ATF4. In this study, we demonstrate that severe hypoxia leads to ER stress and induces ATF4-dependent autophagy through LC3 as a survival mechanism. In summary, we show that ATF4 has a key role in the regulation of autophagy in response to ER stress and provide a direct mechanistic link between the UPR and the autophagic machinery.


Subject(s)
Activating Transcription Factor 4/physiology , Autophagy/genetics , Activating Transcription Factor 4/antagonists & inhibitors , Activating Transcription Factor 4/genetics , Antineoplastic Agents/pharmacology , Autophagy/drug effects , Base Sequence , Boronic Acids/pharmacology , Bortezomib , Cell Hypoxia/drug effects , Cell Hypoxia/physiology , Dose-Response Relationship, Drug , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/metabolism , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , HCT116 Cells , HeLa Cells , Humans , Neoplasms/genetics , Neoplasms/metabolism , Neoplasms/pathology , Oligonucleotide Array Sequence Analysis , Oxygen/pharmacology , Pyrazines/pharmacology , RNA, Small Interfering/pharmacology , Tumor Cells, Cultured , Unfolded Protein Response/drug effects , Unfolded Protein Response/genetics , Validation Studies as Topic
18.
J Med Imaging Radiat Oncol ; 54(1): 82-9, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20377721

ABSTRACT

The aim of this paper is to detail the experience obtained in implementing an image-guided radiation therapy program at the Northern Sydney Cancer Centre. This required retrofitting a Varian Clinac 21EX with an on-board imager. The commissioning and quality assurance procedures, organisation of a multidisciplinary image guided radiation therapy group, and the development of clinical protocols for orthogonal kV and cone beam computed tomography implementation are described. Reassessment of the image-guided radiation therapy program has continued as new equipment and software versions were made available in the department.


Subject(s)
Cone-Beam Computed Tomography/methods , Radiography, Interventional , Radiotherapy/methods , Clinical Protocols , Humans , Inservice Training , New South Wales , Program Development , Program Evaluation , Radiation Dosage , Software
19.
Invest New Drugs ; 28(3): 276-83, 2010 Jun.
Article in English | MEDLINE | ID: mdl-19357810

ABSTRACT

Heparan sulfate mimetics, which we have called the PG500 series, have been developed to target the inhibition of both angiogenesis and heparanase activity. This series extends the technology underpinning PI-88, a mixture of highly sulfated oligosaccharides which reached Phase III clinical development for hepatocellular carcinoma. Advances in the chemistry of the PG500 series provide numerous advantages over PI-88. These new compounds are fully sulfated, single entity oligosaccharides attached to a lipophilic moiety, which have been optimized for drug development. The rational design of these compounds has led to vast improvements in potency compared to PI-88, based on in vitro angiogenesis assays and in vivo tumor models. Based on these and other data, PG545 has been selected as the lead clinical candidate for oncology and is currently undergoing formal preclinical development as a novel treatment for advanced cancer.


Subject(s)
Anticoagulants/therapeutic use , Antineoplastic Agents/therapeutic use , Glucuronidase/antagonists & inhibitors , Heparitin Sulfate/analogs & derivatives , Heparitin Sulfate/therapeutic use , Neoplasms/drug therapy , Neovascularization, Pathologic/drug therapy , Anticoagulants/pharmacology , Antineoplastic Agents/pharmacology , Cell Line , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Discovery/methods , Drug Evaluation, Preclinical/methods , Fibroblast Growth Factor 1/metabolism , Fibroblast Growth Factor 2/metabolism , Heparitin Sulfate/pharmacology , Humans , Structure-Activity Relationship , Vascular Endothelial Growth Factor A/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...