Citations

AbstractPurpose: To determine the response rate to oral capsular fenretinide in children with recurrent or biopsy proven refractory high-risk neuroblastoma.Experimental Design: Patients received 7 days of fenretinide: 2,475 mg/m2/d divided TID (<18 years) or 1,800 mg/m2/d divided BID (≥18 years) every 21 days for a maximum of 30 courses. Patients with stable or responding disease after course 30 could request additional compassionate courses. Best response by course 8 was evaluated in stratum 1 (measurable disease on CT/MRI ± bone marrow and/or MIBG avid sites) and stratum 2 (bone marrow and/or MIBG avid sites only).Results: Sixty-two eligible patients, median age 5 years (range 0.6–19.9), were treated in stratum 1 (n = 38) and stratum 2 (n = 24). One partial response (PR) was seen in stratum 2 (n = 24 evaluable). No responses were seen in stratum 1 (n = 35 evaluable). Prolonged stable disease (SD) was seen in 7 patients in stratum 1 and 6 patients in stratum 2 for 4 to 45+ (median 15) courses. Median time to progression was 40 days (range 17–506) for stratum 1 and 48 days (range 17–892) for stratum 2. Mean 4-HPR steady-state trough plasma concentrations were 7.25 μmol/L (coefficient of variation 40–56%) at day 7 course 1. Toxicities were mild and reversible.Conclusions: Although neither stratum met protocol criteria for efficacy, 1 PR + 13 prolonged SD occurred in 14/59 (24%) of evaluable patients. Low bioavailability may have limited fenretinide activity. Novel fenretinide formulations with improved bioavailability are currently in pediatric phase I studies. Clin Cancer Res; 17(21); 6858–66. ©2011 AACR.

AbstractThe contributions of the host microenvironment to the pathogenesis of multiple myeloma, including progression from the non-malignant disorder monoclonal gammopathy of undetermined significance, are poorly understood. In the present study, microarray analysis of a murine model requiring a unique host microenvironment for myeloma development identified decreased host-derived adiponectin compared with normal mice. In support, clinical analysis revealed decreased serum adiponectin concentrations in monoclonal gammopathy of undetermined significance patients who subsequently progressed to myeloma. We investigated the role of adiponectin in myeloma pathogenesis and as a treatment approach, using both mice deficient in adiponectin and pharmacologic enhancement of circulating adiponectin. Increased tumor burden and bone disease were observed in myeloma-bearing adiponectin-deficient mice, and adiponectin was found to induce myeloma cell apoptosis. The apolipoprotein peptide mimetic L-4F was used for pharmacologic enhancement of adiponectin. L-4F reduced tumor burden, increased survival of myeloma-bearing mice, and prevented myeloma bone disease. Collectively, our studies have identified a novel mechanism whereby decreased host-derived adiponectin promotes myeloma tumor growth and osteolysis. Furthermore, we have established the potential therapeutic benefit of increasing adiponectin for the treatment of myeloma and the associated bone disease.

Abstract With recent approval of the first dendritic cell (DC) vaccine for patient use, many other DC vaccine approaches are now being tested in clinical trials. Many of these DC vaccines employ tumor cell lysates (TL) generated from cells cultured in atmospheric oxygen (∼20% O2) that greatly exceeds levels found in tumors in situ. In this study, we tested the hypothesis that TLs generated from tumor cells cultured under physiologic oxygen (∼5% O2) would be more effective as a source for DC antigens. Gene expression patterns in primary glioma cultures established at 5% O2 more closely paralleled patient tumors in situ and known immunogenic antigens were more highly expressed. DCs treated with TLs generated from primary tumor cells maintained in 5% O2 took up and presented antigens to CD8 T cells more efficiently. Moreover, CD8 T cells primed in this manner exhibited superior tumoricidal activity against target cells cultured in either atmospheric 20% O2 or physiologic 5% O2. Together, these results establish a simple method to greatly improve the effectiveness of DC vaccines in stimulating the production of tumoricidal T cells, with broad implications for many of the DC-based cancer vaccines being developed for clinical application. Cancer Res; 71(21); 6583–9. ©2011 AACR.

Background: Axonal damage and inflammatory demyelination both occur in multiple sclerosis (MS). Some studies suggest that statins, through pleiotropic effects, reduce inflammatory episodes and protect neurons. However, other studies suggest statins have disparate impacts on these pathologic processes. Objective: The objective of this study was to assess disability progression in MS patients receiving statin therapy. Methods: We performed a retrospective medical record review of an established population-based MS prevalence cohort in Olmsted County, Minnesota, comparing disability progression between patients receiving statins and controls. Results: Duration of statin use ranged from 1.9 to 20.3 years with a mean and standard deviation of 6.8 ± 4 years. Years between assessments ranged from 0.6 to 8.2 (75% of patients having intervals >6.4 years). The median (interquartile range) absolute change of disability among the statin group was 0 (0 to +1), compared with +0.5 (0, +1) in the no-statin group. Distributions were not significantly different ( p = 0.39). The mean (standard deviation) absolute change of disability scores among the statin group was +0.69 (+1.49), not significantly different from +0.61 (+1.31) in the no-statin group. Likewise, annualized disability scores did not differ significantly ( p = 0.23). Eighteen (40%) patients worsened by 1.0 or more on Expanded Disability Status Scale (EDSS) in the statin group and 36 (40%) in the no-statin group ( p = 0.85, chi-squared test). Conclusions: In this cohort, disability progression did not differ between those receiving statin therapy and controls. These findings support the hypothesis that statins, in doses currently prescribed for hyperlipidemia, do not affect the long-term course of MS.

The risk of hemorrhage from an intracerebral cavernous malformation has been estimated at 2%–4% per year. In patients with multiple cavernous malformations, typically there are 1 or 2 dominant lesions that result in symptoms. This report highlights an unusual case of recurrent hemorrhage from de novo cavernous malformations. This 35-year-old man had a generalized seizure in 2007. Magnetic resonance imaging performed at the time showed multiple hemorrhagic lesions suggestive of cavernous malformations. Two years later, the patient had clinical symptoms referable to a midbrain hemorrhage. This lesion was not present on 2007 standard and gradient echo images. One year later, the patient had another clinical hemorrhage at the cervical medullary junction. This lesion was also not present on earlier imaging. Genetic testing was negative for the known familial types of cavernous malformation. A lesion was biopsied to ensure correct diagnosis, and the results were pathologically consistent with a cavernous malformation. The patient had a fourth clinical hemorrhage in 2011 from a separate lesion. All hemorrhage symptoms were mild, and he returned to normal functioning and work after each hemorrhage. This case highlights several unusual features of the known natural history of intracerebral cavernous malformations. In this case, resection of the hemorrhagic lesion would not have altered future hemorrhage risk since each new hemorrhage was from a de novo lesion.

Background The etiology of carpal tunnel syndrome (CTS) remains idiopathic in many cases. Noninflammatory fibrosis of the subsynovial connective tissue (SSCT) within the carpal tunnel is common in CTS, and some clinicians have hypothesized that this fibrosis might be a cause rather than an effect of CTS. An animal model in which to test this hypothesis would be useful. The principal objective of this study was to investigate the effect of a surgical injury on SSCT fibrosis and median nerve function within the carpal tunnel in an in vivo rabbit model. Methods Rabbits were sacrificed 12 weeks after surgery and were evaluated by mechanical testing, histology, transmission and scanning electron microscopy, and electrophysiology. Results SSCT fibroblast density ( p<0.0001) and collagen fiber size ( p=0.0004) were significantly higher, and the median nerve distal motor amplitude was significantly lower ( p=0.0018), in the tendon injury group SSCT than in either the sham or control groups. Conclusions Our findings are similar to those seen in patients with carpal tunnel syndrome and suggest that the tendon injury procedure may be the basis of a new animal model of SSCT injury and, possibly, CTS.

AbstractBackground and AimsLiver‐related clinical consequences of non‐alcoholic fatty liver disease (NAFLD) are seen only in the minority of patients with advanced fibrosis. The aim of our study was to generate insight into a potential endocrine basis of steatohepatitis with advanced fibrosis in NAFLD.MethodsBiopsy and blood samples were prospectively collected from patients with medically complicated obesity. Patients were categorized, according to liver histology, into: (i) normal, (ii) simple steatosis (SS), (iii) non‐alcoholic steatohepatitis (NASH) with fibrosis stage (FS) 0–1 and (iv) NASH with FS ≥ 2. A broad panel of potential biomarkers included DHEA‐S, growth hormone (GH), homeostasis model assessment‐insulin resistance (HOMA‐IR), leptin, resistin, adiponectin and cytokeratin 18 (CK‐18) fragments.ResultsWe studied 160 patients (mean BMI 46.8 ± 8.2 kg/m2). Liver biopsies demonstrated normal histology in 10%, SS in 45%, NASH with FS 0–1 in 37.5% and NASH with FS ≥ 2 in 7.5%. C‐reactive protein, IL‐6, GH, CK‐18, adiponectin, HOMA‐IR and quantitative insulin sensitivity check index (QUICKI) were significantly associated with NASH in univariate analysis, but overall predictivity of these parameters was low (AUC ROC = 0.62–0.68). In contrast, all patients with NASH with FS ≥ 2 had insulin resistance, as measured by QUICKI, and GH levels <0.45 ng/ml and all but one patient with NASH FS 2–3 had low DHEA levels (<123 μg/dl).ConclusionsLow serum levels of GH and DHEA are very common in patients with NASH with more advanced fibrosis. Other biomarkers, including CK‐18 fragment levels, have predictivity characteristics that would be of low clinical utility for distinguishing patients with normal histology or SS from those with NASH. These findings demonstrate an endocrine profile associated with advanced fibrosis.

Gastrointestinal (GI) functional and motility disorders are highly prevalent and responsible for long-term morbidity and sometimes mortality in the affected patients. It is estimated that one in three persons has a GI functional or motility disorder. However, diagnosis and treatment of these widespread conditions remains challenging. This partly stems from the multisystem pathophysiology, including processing abnormalities in the central and peripheral (enteric) nervous systems and motor dysfunction in the GI wall. Interstitial cells of Cajal (ICCs) are central to the generation and propagation of the cyclical electrical activity and smooth muscle cells (SMCs) are responsible for electromechanical coupling. In these and other excitable cells voltage-sensitive ion channels (VSICs) are the main molecular units that generate and regulate electrical activity. Thus, VSICs are potential targets for intervention in GI motility disorders. Research in this area has flourished with advances in the experimental methods in molecular and structural biology and electrophysiology. However, our understanding of the molecular mechanisms responsible for the complex and variable electrical behavior of ICCs and SMCs remains incomplete. In this review, we focus on the slow waves and action potentials in ICCs and SMCs. We describe the constituent VSICs, which include voltage-gated sodium (NaV), calcium (CaV), potassium (KV, KCa), chloride (Cl–) and nonselective ion channels (transient receptor potentials [TRPs]). VSICs have significant structural homology and common functional mechanisms. We outline the approaches and limitations and provide examples of targeting VSICs at the pores, voltage sensors and alternatively spliced sites. Rational drug design can come from an integrated view of the structure and mechanisms of gating and activation by voltage or mechanical stress.

ABSTRACT A meeting of clinical microbiologists, representing a diverse group of practice settings, together with representatives from industry partners, discussed the pitfalls of current practices for testing and reporting antimicrobial susceptibility test results. The participants in this session identified several needs. Regarding what antibiotics to test, the discussants noted that the CLSI M100 documents must be readily accessible to all those who need them and presented in a way that is easily understood. Engineering controls (e.g., software programs) are needed that incorporate intrinsic resistance and susceptibility information and contain pathways that would allow the reporting of antibiotics for only those body locations where the antibiotic reaches therapeutic concentrations. These programs should be linked with the patient electronic medical record (EMR) and flag the physician or clinical pharmacist using an active alert messenger when testing reveals that the antibiotic(s) that the patient is receiving may not be optimal or de-escalation of the antibiotic treatment regimen is indicated. Guidelines for the practice of cascade reporting are needed and should be developed to assist laboratories in the identification and reporting of therapeutic and cost-effective antimicrobials. Personalized antibiotic reporting (PAR) software programs are needed that would deduce the optimal antibiotic for each individual patient based on a number of clinical and laboratory features. These would include the following: (i) organism identification; (ii) MIC; (iii) patient-specific factors such as weight, immune status, allergies, creatinine clearance, and albumin level; (iv) site of infection; (v) desired method of dosing (bolus versus continuous infusion); (vi) patient convenience (oral versus intravenous); (vii) drug interactions; and (viii) cost.