Citations

Abstract Purpose: To determine the safety and feasibility of daily i.v. administration of wild-type oncolytic reovirus (type 3 Dearing) to patients with advanced cancer, assess viral excretion kinetics and antiviral immune responses, identify tumor localization and replication, and describe antitumor activity. Experimental Design: Patients received escalating doses of reovirus up to 3 × 1010 TCID50 for 5 consecutive days every 4 weeks. Viral excretion was assessed by reverse transcription-PCR and antibody response by cytotoxicity neutralization assay. Pretreatment and post-treatment tumor biopsies were obtained to measure viral uptake and replication. Results: Thirty-three patients received 76 courses of reovirus from 1 × 108 for 1 day up to 3 × 1010 TCID50 for 5 days, repeated every four weeks. Dose-limiting toxicity was not seen. Common grade 1 to 2 toxicities included fever, fatigue, and headache, which were dose and cycle independent. Viral excretion at day 15 was not detected by reverse transcription-PCR at 25 cycles and only in 5 patients at 35 cycles. Neutralizing antibodies were detected in all patients and peaked at 4 weeks. Viral localization and replication in tumor biopsies were confirmed in 3 patients. Antitumor activity was seen by radiologic and tumor marker (carcinoembryonic antigen, CA19.9, and prostate-specific antigen) evaluation. Conclusions: Oncolytic reovirus can be safely and repeatedly administered by i.v. injection at doses up to 3 × 1010 TCID50 for 5 days every 4 weeks without evidence of severe toxicities. Productive reoviral infection of metastatic tumor deposits was confirmed. Reovirus is a safe agent that warrants further evaluation in phase II studies.

There are opportunities to improve quality and safety of care provided to adult patients. The Plummer Project of the Department of Medicine at the Mayo Clinic (Rochester, MN, USA) is an initiative to redesign outpatient practice. We used multidisciplinary teams to standardize the tasks essential to improve patient care. With the initiative to standardize the rooming process, patient care and safety improved with greater accuracy of the medication list. The standardization also improved physician efficiency because trained clinical assistants helped address the needs of the patient. Physicians were satisfied by the new process and the technology enhancements. Clinical assistants were also highly satisfied by the training process. The quality and safety of patient care can be significantly improved by practice redesign. This practice redesign was satisfying for all, especially the patients, physicians and support team in our practice.

In the newest implementation of cochlear implant surgery, electrode arrays of 10 or 20mm are inserted into the cochlea with the aim of preserving hearing in the region apical to the tip of the electrode array. In the current study two measures were used to assess hearing preservation: changes in audiometric threshold and changes in psychophysical estimates of nonlinear cochlear processing. Nonlinear cochlear processing was evaluated at signal frequencies of 250 and 500Hz using Schroeder phase maskers with various indices of masker phase curvature. A total of 15 normal-hearing listeners and 13 cochlear implant patients (7 with a 10mm insertion and 6 with a 20mm insertion) were tested. Following surgery the mean low-frequency threshold elevation was 12.7dB (125–750Hz). Nine patients had postimplant thresholds within 5–10dB of preimplant thresholds. Only one patient, however, demonstrated a completely normal nonlinear cochlear function following surgery—although most retained some degree of residual nonlinear processing. This result indicates (i) that Schroeder phase masking functions are a more sensitive index of surgical trauma than audiometric threshold and (ii) that preservation of a normal cochlear function in the apex of the cochlea is relatively uncommon but possible.

AbstractA venous thromboembolism (VTE) with the subsequent risk of pulmonary embolism is a major concern in the treatment of patients with multiple myeloma with thalidomide. The susceptibility to developing a VTE in response to thalidomide therapy is likely to be influenced by both genetic and environmental factors. To test genetic variation associated with treatment related VTE in patient peripheral blood DNA, we used a custom-built molecular inversion probe (MIP)–based single nucleotide polymorphism (SNP) chip containing 3404 SNPs. SNPs on the chip were selected in “functional regions” within 964 genes spanning 67 molecular pathways thought to be involved in the pathogenesis, treatment response, and side effects associated with myeloma therapy. Patients and controls were taken from 3 large clinical trials: Medical Research Council (MRC) Myeloma IX, Hovon-50, and Eastern Cooperative Oncology Group (ECOG) EA100, which compared conventional treatments with thalidomide in patients with myeloma. Our analysis showed that the set of SNPs associated with thalidomide-related VTE were enriched in genes and pathways important in drug transport/metabolism, DNA repair, and cytokine balance. The effects of the SNPs associated with thalidomide-related VTE may be functional at the level of the tumor cell, the tumor-related microenvironment, and the endothelium. The clinical trials described in this paper have been registered as follows: MRC Myeloma IX: ISRCTN68454111; Hovon-50: NCT00028886; and ECOG EA100: NCT00033332.

Abstract Two cytidine analogues, gemcitabine (dFdC) and 1-β-d-arabinofuranosylcytosine (AraC), show significant therapeutic effect in a variety of cancers. However, response to these drugs varies widely. Evidence from tumor biopsy samples shows that expression levels for genes involved in the cytidine transport, metabolism, and bioactivation pathway contribute to this variation in response. In the present study, we set out to test the hypothesis that variation in gene expression both within and outside of this “pathway” might influence sensitivity to gemcitabine and AraC. Specifically, Affymetrix U133 Plus 2.0 GeneChip and cytotoxicity assays were performed to obtain basal mRNA expression and IC50 values for both drugs in 197 ethnically defined Human Variation Panel lymphoblastoid cell lines. Genes with a high degree of association with IC50 values were involved mainly in cell death, cancer, cell cycle, and nucleic acid metabolism pathways. We validated selected significant genes by performing real-time quantitative reverse transcription-PCR and selected two representative candidates, NT5C3 (within the pathway) and FKBP5 (outside of the pathway), for functional validation. Those studies showed that down-regulation of NT5C3 and FKBP5 altered tumor cell sensitivity to both drugs. Our results suggest that cell-based model system studies, when combined with complementary functional characterization, may help to identify biomarkers for response to chemotherapy with these cytidine analogues. [Cancer Res 2008;68(17):7050–8]

The neuropilin (Nrp)1 receptor is essential for both nervous and vascular system development. Nrp1 is unusually versatile, because it transmits both chemoattractive and repulsive signals in response to vascular endothelial growth factor (VEGF)-A and class 3 semaphorins, respectively. Both Nrp1 and VEGF receptor 2 undergo ligand-dependent endocytosis. We sought to establish the endocytic pathway of Nrp1 and to determine whether uptake is required for its signaling. Whereas Nrp1 underwent clathrin-dependent endocytosis in response to VEGFA 165 treatment, semaphorin 3C (sema3C) induced lipid raft–dependent endocytosis. The myosin VI PDZ (postsynaptic density 95, Disk large, Zona occludens-1) adaptor protein synectin was essential for Nrp1 trafficking. Sema3C failed to inhibit migration of synectin −/− endothelial cells, mirroring the lower migratory response of these cells to VEGFA 165 . These results show that the endocytic pathway of Nrp1 is determined by its ligand and that the trafficking of Nrp1 is essential for its signaling.

Natural and synthetic hydrogels have attracted much attention for nerve regeneration. Previous studies have shown that electrical charge has significant effect on stimulation of neurite outgrowth. In this work, incorporation of a positively charged monomer into the photocrosslinkable oligo(polyethylene glycol) fumarate (OPF) hydrogel has been investigated. We have evaluated the effect of localized positive charge on neurite outgrowth in culture with an objective that positively charged hydrogels ultimately can be used for stimulating in vivo nerve regeneration. The effect of charged modification has been also studied on mechanical properties and swelling ratio of these hydrogels. Our data indicated that with increasing charge density hydrogels swelling ratio increased in water, however it remained constant in PBS. We also demonstrated that compressive modulus and tensile strength of the hydrogels improved with incorporation of electrical charge into the hydrogels. Biodegradation of modified hydrogels was investigated in a series of biomimetic solutions. OPF hydrogels appeared to be more susceptible to oxidative degradation as opposed to the hydrolytic degradation in enzymes and acidic solution, and the degradation rate was correlated to the PEG molecular weight and charge density of the hydrogels. To investigate the effect of charge modification on nerve cell attachment and differentiation, dissociated dorsal root ganglion (DRG) cells were plated onto the modified and unmodified hydrogels surfaces. DRG cells attached and extended their neurites more readily on the surface of positively charged hydrogels as opposed to the unmodified hydrogels.

The aims of this research were to examine the neural expression profile of undifferentiated mesenchymal stem cells (MSCs), to define a serum-free environment that would support the survival of MSCs, and to assess the effects of elevated cyclic adenosine monophosphate (cAMP) levels on MSC morphology and expression of neural markers. The neural profile of MSCs was assessed using immunocytochemistry and real-time polymerase chain reaction (PCR) techniques. These MSCs were then cultured in varying serum-free environments, with flow cytometry analysis of cell viability and apoptosis. The effects of forskolin and 8 bromo-cAMP treatment on MSC morphology and expression of neural markers were assessed using light microscopy, immunocytochemistry and real-time PCR analysis. Expression of the neural markers nestin, vimentin, β III tubulin, glial fibrillary acidic protein, and the tropomyosin-related kinases was demonstrated in normal undifferentiated MSCs. Furthermore, MSCs cultured in serum-free conditions containing ascorbic acid 2-phosphate demonstrated greater long-term survival and reduced apoptosis. In contrast, forskolin increased the percentage of cells undergoing apoptosis. Culture in the presence of forskolin induced a 6-fold increase in β III tubulin expression after a 6-h exposure time, which was accompanied by dramatic changes in morphology. However, this effect was transient, with the cells reverting to their normal morphology by 24 h. Treatment with 8 bromo-cAMP induced similar increases in β III tubulin expression without such dramatic morphological changes. Factors which increase the concentration of cAMP induce transient changes in expression of neural markers that appear to be the result of cellular adaptation to changes in culture conditions rather than a real process of neural differentiation.