Mechanistic and prognostic significance of aberrant methylation in the molecular pathogenesis of human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide, accounting for an estimated 600,000 deaths annually. Aberrant methylation, consisting of DNA hypomethylation and/or promoter gene CpG hypermethylation, is implicated in the development of a variety of solid tumors, including HCC. We analyzed the global levels of DNA methylation as well as the methylation status of 105 putative tumor suppressor genes and found that the extent of genome-wide hypomethylation and CpG hypermethylation correlates with biological features and clinical outcome of HCC patients. We identified activation of Ras and downstream Ras effectors (ERK, AKT, and RAL) due to epigenetic silencing of inhibitors of the Ras pathway in all HCC. Further, selective inactivation of SPRY1 and -2, DAB2, and SOCS4 and -5 genes and inhibitors of angiogenesis (BNIP3, BNIP3L, IGFBP3, and EGLN2) was associated with poor prognosis. Importantly, several epigenetically silenced putative tumor suppressor genes found in HCC were also inactivated in the nontumorous liver. Our results assign both therapeutic and chemopreventive significance to methylation patterns in human HCC and open the possibility of using molecular targets, including those identified in this study, to effectively inhibit HCC development and progression.     

Adenovirus-mediated transfer of an Na+/K+-ATPase beta1 subunit gene improves alveolar fluid clearance and survival in hyperoxic rats

Pulmonary edema is cleared via active Na(+) transport by alveolar epithelial Na(+)/K(+)-ATPases and Na(+) channels. Rats exposed to acute hyperoxia have a high mortality rate, decreased Na(+)/K(+)-ATPase function, and decreased alveolar fluid clearance (AFC). We hypothesized that Na(+)/K(+)-ATPase subunit gene overexpression could improve AFC in rats exposed to hyperoxia. We delivered 4 x 10(9) PFU of recombinant adenoviruses containing rat alpha(1) and beta(1) Na(+)/K(+)-ATPase subunit cDNAs (adalpha(1) and adbeta(1), respectively) to rat lungs 7 days prior to exposure to 100% O(2) for 64 hr. As compared with controls and ad alpha(1), AFC in the adbeta(1) rats was increased by >300%. Permeability for large solutes was less in the ad beta(1) than in the other hyperoxia groups. Glutathione oxidation, but not superoxide dismutase activity, was increased only in the adbeta(1) group. Survival through 14 days of hyperoxia was 100% in the adbeta(1) group but was not different from hyperoxic controls in animals given adalpha(1). Our data show that overexpression of a beta(1) Na(+)/K(+)-ATPase subunit augments AFC and improves survival in this model of acute lung injury via antioxidant-independent mechanisms. Conceivably, restoration of AFC via gene transfer of Na(+)/K(+)-ATPase subunit genes may prove useful for the treatment of acute lung injury and pulmonary edema.     

Gene therapy for diabetic peripheral neuropathy: A randomized,placebo‐controlled phase III study of VM202, a plasmid DNA encoding human hepatocyte growth factor

AbstractVM202 is a plasmid DNA encoding two isoforms of hepatocyte growth factor (HGF). A previous phase II study in subjects with painful diabetic peripheral neuropathy (DPN) showed significant reductions in pain. A phase III study was conducted to evaluate the safety and efficacy of VM202 in DPN. The trial was conducted in two parts, one for 9 months (DPN 3‐1) with 500 subjects (VM202: 336 subjects; and placebo: 164) and a preplanned subset of 101 subjects (VM202: 65 subjects; and placebo: 36) with a noninterventional extension to 12 months (DPN 3‐1b). VM202 or placebo was administered to calf muscles on days 0 and 14, and on days 90 and 104. The primary end point in DPN 3‐1 was change from baseline in the mean 24‐h Numerical Rating Scale (NRS) pain score. In DPN 3‐1b, the primary end point was safety, whereas the secondary efficacy end point was change in the mean pain score. VM202 was well‐tolerated in both studies without significant adverse events. VM202 failed to meet its efficacy end points in DPN 3‐1. In DPN 3‐1b, however, VM202 showed significant and clinically meaningful pain reduction versus placebo. Pain reduction in DPN 3‐1b was even greater in subjects not receiving gabapentin or pregabalin, confirming an observation noted in the phase II study. In DPN 3‐1b, symptomatic relief was maintained for 8 months after the last injection suggesting that VM202 treatment might change disease progression. Despite the perplexing discrepancy between the two studies, the safety and long‐lasting pain‐relieving effects of VM202 observed in DPN 3‐1b warrant another rigorous phase III study. Study Highlights

• WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC?

Current therapies for painful diabetic peripheral neuropathy (DPN) are palliative and do not target the underlying mechanisms. Moreover, symptomatic relief is often limited with existing neuropathic pain drugs. Thus, there is a great medical need for safer and effective treatments for DPN.

• WHAT QUESTION DID THIS STUDY ADDRESS?

Can nonviral gene delivery of hepatocyte growth factor reduce pain in patients with DPN and potentially modify progression of the disorder?

• WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE?

Nonviral gene therapy can be used safely and practically to treat DPN.

• HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE?

As the first gene medicine to enter advanced clinical trials for the treatment of DPN, this study provides the proof of concept of an entirely new potential approach to the disorder.     

A parallel software architecture for building intelligent medical monitors

Intensive care units become more complicated each day as the number of devices developed to monitor various aspects of a patient's status continues to increase. Intelligent monitors attempt to reduce this complexity by interpreting the data and presenting a high level summary to the clinician. We propose an innovative parallel software architecture for constructing intelligent medical monitors: theprocess trellis. The process trellis is an explicitly parallel structure, and therefore can take advantage of the performance gains available from parallel computing hardware. It does not, however, presuppose any expertise in parallel programming on the part of the application programmer. A prototype cardiovascular monitor has been built using this parallel software architecture. Preliminary testing of the monitor has shown that real-time cardiovascular monitoring, including data calculations, symbolic classification, and interpretation can be accomplished in real-time.This paper is a revised version of a paper originally published in the Proceedings of the 13th Annual Symposium on Computer Applications in Medical Care held in Washington, D.C. November 5–9, 1989. (Edited by Lawrence C. Kingsland III).In the past referred to as the process lattice [1].     

Emergency department presentations of patients with Parkinson's disease

Parkinson's disease (PD) is a chronic progressive neurological disorder characterized by tremor, muscle rigidity, slowness of movement (bradykinesia), and gait instability. In early disease, PD is well managed in an office setting, however, as the disease progresses, a variety of syndromes may result in emergency department visits. The scenarios most likely to require an emergent evaluation are severe motor "off" periods with immobility, involuntary movements (dyskinesia), psychosis, acute confusion, panic disorder, and pain. Other less frequent presentations are also discussed. This article uses illustrative cases to provide a framework to discuss emergency department diagnosis and management issues in caring for these patients.     

Cardiac alpha-myosin heavy chains differ in their induction of myocarditis. Identification of pathogenic epitopes.

BALB/c mice develop autoimmune myocarditis after immunization with mouse cardiac myosin, whereas C57B/6 mice do not. To define the immunogenicity and pathogenicity of cardiac myosin in BALB/c mice, we immunized mice with different forms of cardiac myosin. These studies demonstrate the discordance of immunogenicity and pathogenicity of myosin heavy chains. The cardiac alpha-myosin heavy chains of BALB/c and C57B/6 mice differ by two residues that are near the junction of the head and rod in the S2 fragment of myosin. Myosin preparations from both strains are immunogenic in susceptible BALB/c as well as in nonsusceptible C57B/6 mice; however, BALB/c myosin induces a greater incidence of disease. To further delineate epitopes of myosin heavy chain responsible for immunogenicity and disease, mice were immunized with fragments of genetically engineered rat alpha cardiac myosin. Epitopes in the region of difference between BALB/c and C57B/6 (residues 735-1032) induce disease in both susceptible and nonsusceptible mice. The data presented here demonstrate that pathogenic epitopes of both mouse and rat myosin residue in the polymorphic region of the S2 subunit. In addition, these studies suggest that polymorphisms in the autoantigen may be part of the genetic basis for autoimmune myocarditis.     

Lipoprotein particles, insulin, adiponectin, C-reactive protein and risk of coronary heart disease among men with metabolic syndrome

We tested the hypotheses whether nuclear magnetic resonance (NMR) determined lipoprotein particles, insulin and adiponectin, and C-reactive protein (CRP) and white blood cell (WBC) count as markers of inflammation predicted risk of coronary heart disease (CHD) death among 428 men age 35-57 years with metabolic syndrome (MetSyn) in a matched case control study within the multiple risk factor intervention trial. Blood samples collected at entry into the study and stored at -60 degrees C were obtained from central storage for blood analyte analysis. Two hundred and fourteen men with MetSyn who died of CHD were matched with 214 men with MetSyn who did not die of CHD during 18 years of follow-up. Cases were matched to controls on age, study group, number of factors present in the MetSyn, and presence or absence of a nonfatal CVD event during the trial. Mortality follow-up was determined using the National Death Index. Higher levels of high density lipoprotein particles (HDL-P), especially medium-sized HDL-P [hazard ratio (95% confidence interval) 0.45 (0.25-0.83, P<0.01), quartile 1 as compared to quartile 4], were associated with lower risk of CHD death. Low density lipoprotein (LDL) particles were not associated with increased risk of CHD. Elevated LDL cholesterol (LDL-C), smoking and WBC count were, but levels of adiponectin, insulin and CRP were not significantly related to CHD death. In multivariate models adjusting for smoking and LDL-C, medium HDL-P and WBC count remained independent predictors of CHD death. Number of HDL particles, especially medium-sized HDL particles and WBC count were independent predictors of CHD death among men with MetSyn.     

Clinical review: Airway hygiene in the intensive care unit

Maintenance of airway secretion clearance, or airway hygiene, is important for the preservation of airway patency and the prevention of respiratory tract infection. Impaired airway clearance often prompts admission to the intensive care unit (ICU) and can be a cause and/or contributor to acute respiratory failure. Physical methods to augment airway clearance are often used in the ICU but few are substantiated by clinical data. This review focuses on the impact of oral hygiene, tracheal suctioning, bronchoscopy, mucus-controlling agents, and kinetic therapy on the incidence of hospital-acquired respiratory infections, length of stay in the hospital and the ICU, and mortality in critically ill patients. Available data are distilled into recommendations for the maintenance of airway hygiene in ICU patients.     

Loss of hepatocyte growth factor/c-Met signaling pathway accelerates early stages of N-nitrosodiethylamine induced hepatocarcinogenesis

Hepatocyte growth factor (HGF) has been reported to have both positive and negative effects on carcinogenesis. Here, we show that the loss of c-Met signaling in hepatocytes enhanced rather than suppressed the early stages of chemical hepatocarcinogenesis. c-Met conditional knockout mice (c-metfl/fl, AlbCre+/-; MetLivKO) treated with N-nitrosodiethylamine developed significantly more and bigger tumors and with a shorter latency compared with control (w/w, AlbCre+/-; Cre-Ctrl) mice. Accelerated tumor development was associated with increased rate of cell proliferation and prolonged activation of epidermal growth factor receptor (EGFR) signaling. MetLivKO livers treated with N-nitrosodiethylamine also displayed elevated lipid peroxidation, decreased ratio of reduced glutathione to oxidized glutathione, and up-regulation of superoxide dismutase 1 and heat shock protein 70, all consistent with increased oxidative stress. Likewise, gene expression profiling done at 3 and 5 months after N-nitrosodiethylamine treatment revealed up-regulation of genes associated with cell proliferation and stress responses in c-Met mutant livers. The negative effects of c-Met deficiency were reversed by chronic p.o. administration of antioxidant N-acetyl-L-cysteine. N-acetyl-L-cysteine blocked the EGFR activation and reduced the N-nitrosodiethylamine-initiated hepatocarcinogenesis to the levels of Cre-Ctrl mice. These results argue that intact HGF/c-Met signaling is essential for maintaining normal redox homeostasis in the liver and has tumor suppressor effect(s) during the early stages of N-nitrosodiethylamine-induced hepatocarcinogenesis.