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1.
BMC Prim Care ; 25(1): 235, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961340

ABSTRACT

BACKGROUND: We initially reported on the cost-effectiveness of a 6-month randomized controlled implementation trial which evaluated Health TAPESTRY, a primary care program for older adults, at the McMaster Family Health Team (FHT) site and 5 other FHT sites in Ontario, Canada. While there were no statistically significant between-group differences in outcomes at month 6 post randomization, positive outcomes were observed at the McMaster FHT site, which recruited 40% (204/512) of the participants. The objective of this post-hoc study was to determine the cost-effectiveness of Health TAPESTRY based on data from the McMaster FHT site. METHODS: Costs included the cost to implement Health TAPESTRY at McMaster as well as healthcare resource consumed, which were costed using publicly available sources. Health-related-quality-of-life was evaluated with the EQ-5L-5L at baseline and at month 6 post randomization. Quality-adjusted-life-years (QALYs) were calculated under an-area-under the curve approach. Unadjusted and adjusted regression analyses (two independent regression analyses on costs and QALYs, seemingly unrelated regression [SUR], net benefit regression) as well as difference-in-difference and propensity score matching (PSM) methods, were used to deal with the non-randomized nature of the trial. Sampling uncertainty inherent to the trial data was estimated using non-parametric bootstrapping. The return on investment (ROI) associated with Health TAPESTRY was calculated. All costs were reported in 2021 Canadian dollars. RESULTS: With an intervention cost of $293/patient, Health TAPESTRY was the preferred strategy in the unadjusted and adjusted analyses. The results of our bootstrap analyses indicated that Health TAPESTRY was cost-effective compared to usual care at commonly accepted WTP thresholds. For example, if decision makers were willing to pay $50,000 per QALY gained, the probability of Health TAPESTRY to be cost effective compared to usual care varied from 0.72 (unadjusted analysis) to 0.96 (SUR) when using a WTP of $50,000/QALY gained. The DID and ROI analyses indicated that Health Tapestry generated a positive ROI. CONCLUSION: Health TAPESTRY was the preferred strategy when implemented at the McMaster FHT. We caution care in interpreting the results because of the post-hoc nature of the analyses and limited sample size based on one site.


Subject(s)
Cost-Benefit Analysis , Primary Health Care , Quality-Adjusted Life Years , Humans , Primary Health Care/economics , Aged , Female , Male , Ontario , Quality of Life , Aged, 80 and over , Cost-Effectiveness Analysis
2.
Rev Sci Instrum ; 92(5): 054502, 2021 May 01.
Article in English | MEDLINE | ID: mdl-34243344

ABSTRACT

We describe a torsion pendulum with a large mass-quadrupole moment and a resonant frequency of 2.8 mHz, whose angle is measured using a Michelson interferometer. The system achieved noise levels of ∼200prad/Hz between 0.2 and 30 Hz and ∼10prad/Hz above 100 Hz. Such a system can be applied to a broad range of fields from the study of rotational seismic motion and elastogravity signals to gravitational wave observation and tests of gravity.

3.
Ann Oncol ; 27(12): 2288-2294, 2016 12.
Article in English | MEDLINE | ID: mdl-27637745

ABSTRACT

BACKGROUND: The effect of immunologic and targeted agents on intracranial response rates in patients with melanoma brain metastases (MBMs) is not yet clearly understood. This report analyzes outcomes of intact MBMs treated with single-session stereotactic radiosurgery (SRS) and anti-PD-1 therapy, anti-CTLA-4 therapy, BRAF/MEK inhibitors(i), BRAFi, or conventional chemotherapy. PATIENTS AND METHODS: Patients were included if MBMs were treated with single-session SRS within 3 months of receiving systemic therapy. The primary end point of this study was distant MBM control. Secondary end points were local MBM control defined as a >20% volume increase on follow-up MRI, systemic progression-free survival, overall survival (OS) from both SRS and cranial metastases diagnosis, and neurotoxicity. Images were reviewed alongside two neuro-radiologists at our institution. RESULTS: Ninety-six patients were treated to 314 MBMs over 119 SRS treatment sessions between January 2007 and August 2015. No significant differences were noted in age (P = 0.27), gender (P = 0.85), treated gross tumor volume (P = 0.26), or the diagnosis-specific graded prognostic assessment (P = 0.51) between the treatment cohorts. Twelve-month Kaplan-Meier (KM) distant MBM control rates were 38%, 21%, 20%, 8%, and 5% (P = 0.008) for SRS with anti-PD-1 therapies, anti-CTLA-4 therapy, BRAF/MEKi, BRAFi, and conventional chemotherapy, respectively. No significant differences were noted in the KM local MBM control rates among treatment groups (P = 0.25). Treatment with anti-PD-1 therapy, anti-CTLA-4 therapy, or BRAF/MEKi significantly improved OS on both univariate and multivariate analyses when compared with conventional chemotherapy. CONCLUSION: In our institutional analysis of patients treated with SRS and various systemic immunologic and targeted melanoma agents, significant differences in distant MBM control and OS are noted. Prospective evaluation of the potential synergistic effect between these agents and SRS is warranted.


Subject(s)
Brain Neoplasms/drug therapy , Brain Neoplasms/surgery , Melanoma/drug therapy , Melanoma/surgery , Radiosurgery , Acrylonitrile/administration & dosage , Acrylonitrile/analogs & derivatives , Adolescent , Adult , Aged , Aged, 80 and over , Aniline Compounds/administration & dosage , Brain Neoplasms/pathology , Brain Neoplasms/secondary , CTLA-4 Antigen/antagonists & inhibitors , CTLA-4 Antigen/genetics , Combined Modality Therapy , Disease-Free Survival , Female , Humans , Male , Melanoma/genetics , Melanoma/pathology , Middle Aged , Neoplasm Metastasis , Prognosis , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/genetics , Proto-Oncogene Proteins B-raf/antagonists & inhibitors , Proto-Oncogene Proteins B-raf/genetics
4.
Neuroscience ; 236: 88-98, 2013 Apr 16.
Article in English | MEDLINE | ID: mdl-23380500

ABSTRACT

Excitability, neurite outgrowth and their specification are very important features in the establishment of neuronal differentiation. We have studied a conditioned medium (CM) from sciatic nerve which is able to induce a neuronal-like differentiation of PC12 cells. Previously, we have demonstrated that supplementing this CM with a generic inhibitor (k252a), which mainly inhibits tropomyosin-related kinase receptors (Trk receptors) and protein kinase C (PKC), caused neurite elongation, sodium current induction and axon development. In the present work, we are showing that the enhancement of neurite length and induction of sodium currents induced by CM+k252a were prevented by ErbB receptor inhibition. Additionally, we demonstrated that specific inhibition of PKC produced a similar effect to that exerted by k252a in CM-treated cells, specifically by increasing the percentage of differentiated cells with long neurites and inducing sodium currents. Moreover, CM changed the mRNA levels for ErbB2 and ErbB3 increasing them 6- and 36-folds respectively compared to their control. The inclusion of k252a with CM changed the ErbB1, ErbB2 and ErbB3 mRNA proportions increasing those eight-, seven- and fivefolds respectively. From this point, it is clear that appropriate ErbB receptor levels and PKC inhibition are necessary to enhance the effect of the CM in inducing the neuronal-like differentiation of PC12 cells. In summary, we demonstrated the involvement of ErbB receptors in the regulation of neurite elongation and sodium current induction in PC12 cells and propose that these processes could be initiated by ErbB receptors followed by a fine regulation of PKC signaling. These findings might implicate a novel interplay between ErbB receptors and PKC in the regulation of these molecular mechanisms.


Subject(s)
ErbB Receptors/metabolism , Neurons/cytology , Neurons/metabolism , Protein Kinase C/metabolism , Receptor, ErbB-2/metabolism , Receptor, ErbB-3/metabolism , Animals , Cell Differentiation/physiology , Culture Media, Conditioned/pharmacology , Humans , Immunohistochemistry , Membrane Potentials/physiology , Neurogenesis/drug effects , Neurogenesis/physiology , Neurons/drug effects , PC12 Cells , Patch-Clamp Techniques , Rats , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Signal Transduction/physiology
5.
J Insect Physiol ; 58(12): 1676-85, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23085555

ABSTRACT

We describe the effects of six bactridines (150 nM) on cricket dorsal unpaired median (DUM) neurons. The addition of bactridine 2 to DUM neurons induced a large current component with a reversal potential more negative than -30 mV, most evident at the end of the pulses. This current was completely suppressed when 1 µM amiloride was applied before adding the bactridines. Since the amiloride sensitive current is able to distort the aim of our study, i.e. the effect of bactridines on sodium channels, all experiments were done in the presence of 1 µM amiloride. Most bactridines induced voltage shifts of V(1/2) of the Boltzmann inactivation voltage dependency curves in the hyperpolarizing direction. Bactridines 1, 4 and 6 reduced Na current peak by 65, 80 and 24% of the control, respectively. The sodium conductance blockage by bactridines was voltage independent at potentials >20 mV. Bactridines effect on cricket DUM neurons does not correspond to neither α- nor ß-toxins. Most bactridines shifted the inactivation curves in the hyperpolarizing direction without any effects on the activation m(∞)-like curves. Also bactridines differ from other NaScpTx in that they increased an amiloride-sensitive conductance in DUM neurons. Our result suggest that the α/ß classification of sodium scorpion toxins is not all encompassing. The present work shows that bactridines target more than one site: insect voltage dependent Na channels and an amiloride-sensitive ionic pathway which is under study.


Subject(s)
Neurons/drug effects , Peptides/pharmacology , Scorpion Venoms/pharmacology , Sodium Channels/drug effects , Amiloride , Animals , Gryllidae , Patch-Clamp Techniques , Scorpions
6.
Neurology ; 77(12): 1156-64, 2011 Sep 20.
Article in English | MEDLINE | ID: mdl-21880994

ABSTRACT

OBJECTIVE: This analysis was performed to assess whether antiepileptic drugs (AEDs) modulate the effectiveness of temozolomide radiochemotherapy in patients with newly diagnosed glioblastoma. METHODS: The European Organization for Research and Treatment of Cancer (EORTC) 26981-22981/National Cancer Institute of Canada (NCIC) CE.3 clinical trial database of radiotherapy (RT) with or without temozolomide (TMZ) for newly diagnosed glioblastoma was examined to assess the impact of the interaction between AED use and chemoradiotherapy on survival. Data were adjusted for known prognostic factors. RESULTS: When treatment began, 175 patients (30.5%) were AED-free, 277 (48.3%) were taking any enzyme-inducing AED (EIAED) and 135 (23.4%) were taking any non-EIAED. Patients receiving valproic acid (VPA) only had more grade 3/4 thrombopenia and leukopenia than patients without an AED or patients taking an EIAED only. The overall survival (OS) of patients who were receiving an AED at baseline vs not receiving any AED was similar. Patients receiving VPA alone (97 [16.9%]) appeared to derive more survival benefit from TMZ/RT (hazard ratio [HR] 0.39, 95% confidence interval [CI] 0.24-0.63) than patients receiving an EIAED only (252 [44%]) (HR 0.69, 95% CI 0.53-0.90) or patients not receiving any AED (HR 0.67, 95% CI 0.49-0.93). CONCLUSIONS: VPA may be preferred over an EIAED in patients with glioblastoma who require an AED during TMZ-based chemoradiotherapy. Future studies are needed to determine whether VPA increases TMZ bioavailability or acts as an inhibitor of histone deacetylases and thereby sensitizes for radiochemotherapy in vivo.


Subject(s)
Brain Neoplasms/drug therapy , Brain Neoplasms/mortality , Dacarbazine/analogs & derivatives , Glioblastoma/drug therapy , Glioblastoma/mortality , Valproic Acid/therapeutic use , Adolescent , Adult , Aged , Antineoplastic Agents, Alkylating/therapeutic use , Canada/epidemiology , Dacarbazine/therapeutic use , Europe/epidemiology , Female , Humans , Male , Middle Aged , Retrospective Studies , Survival Rate/trends , Temozolomide , Young Adult
7.
Br J Cancer ; 104(2): 290-9, 2011 Jan 18.
Article in English | MEDLINE | ID: mdl-21179029

ABSTRACT

BACKGROUND: Although the naturally occurring reovirus causes only mild symptoms in humans, it shows considerable potential as an oncolytic agent because of its innate ability to target cancer cells. In immunocompromised hosts, however, wild-type reovirus can target healthy tissues, including heart, liver, pancreas and neural structures. METHODS: We characterized an attenuated form of reovirus (AV) derived from a persistently infected cell line through sequence analysis, as well as western blot and in vitro transcription and translation techniques. To examine its pathogenesis and oncolytic potential, AV reovirus was tested on healthy embryonic stem cells, various non-transformed and transformed cell lines, and in severe combined immunodeficiency (SCID) mice with tumour xenografts. RESULTS: Sequence analysis of AV reovirus revealed a premature STOP codon in its sigma 1 attachment protein. Western blot and in vitro translation confirmed the presence of a truncated σ1. In comparison to wild-type reovirus, AV reovirus did not kill healthy stem cells or induce black tail formation in SCID mice. However, it did retain its ability to target cancer cells and reduce tumour size. CONCLUSION: Despite containing a truncated attachment protein, AV reovirus still preferentially targets cancer cells, and compared with wild-type reovirus it shows reduced toxicity when administered to immunodeficient hosts, suggesting the potential use of AV reovirus in combination cancer therapy.


Subject(s)
Oncolytic Virotherapy , Reoviridae/pathogenicity , Animals , Base Sequence , Blotting, Western , Cell Line , DNA Primers , Humans , Immunohistochemistry , Mice , Mice, SCID , Microscopy, Electron , Protein Biosynthesis , Reoviridae/genetics , Transcription, Genetic , Transplantation, Heterologous , Virulence
8.
Neuroscience ; 159(2): 550-8, 2009 Mar 17.
Article in English | MEDLINE | ID: mdl-19171180

ABSTRACT

Excitability and axon/dendrite specification are the most distinctive features in the establishment of neuronal polarization. Conditioned medium from rat sciatic nerve (CM) induced a neuronal-like morphology in PC12 cells. Here we show that CM neuritogenic activity is limited to the induction of dendrites in PC12 cells. However, treatment of these cells with CM in combination with a generic inhibitor for tyrosine kinase receptors (k252a) promoted the enhancement of neurite length, development of axons and induction of sodium currents. On the other hand, specific inhibition of TrkA and p75(NTR) receptors in CM-treated cells reduced the neurite length in comparison with cells treated only with CM, although the effect over the induction of sodium currents was continuously observed. These results suggested that CM had some components that, even though are able to start the morphological cell differentiation and produce short neurites (likely acting through TrkA and p75(NTR)), can restrain further neurite extension. Depletion of pro-NGF isoforms from CM produced a similar effect as the exerted by k252a, TrkA and p75(NTR) receptor inhibitors in CM-treated cells, inducing the elicitation of sodium currents. These results suggested that the effect of CM might be mediated through pro-NGF. The difference between the results obtained with the generic inhibitor for Trk receptors and the specific inhibitors for TrkA and p75(NTR) receptors in CM-treated cells, suggested that alternative pathways could be used to regulate neurite elongation, axon specification and sodium currents in PC12 cells. These findings represent important clues to improve the understanding of the initiation of neuronal polarity.


Subject(s)
Nerve Growth Factors/antagonists & inhibitors , Neurites/physiology , PC12 Cells/cytology , Protein Precursors/antagonists & inhibitors , Sciatic Nerve/chemistry , Sodium Channels/metabolism , Analysis of Variance , Animals , Carbazoles/pharmacology , Cell Differentiation/drug effects , Cell Differentiation/physiology , Culture Media, Conditioned/pharmacology , Enzyme Inhibitors/pharmacology , Immunoprecipitation/methods , Indole Alkaloids/pharmacology , Membrane Potentials/drug effects , Membrane Potentials/physiology , Microtubule-Associated Proteins/metabolism , Nerve Growth Factor/pharmacology , Nerve Growth Factors/metabolism , Neurites/drug effects , Neurofilament Proteins/metabolism , PC12 Cells/drug effects , PC12 Cells/physiology , Patch-Clamp Techniques/methods , Protein Precursors/metabolism , Rats , Rats, Sprague-Dawley , Receptor, Nerve Growth Factor/antagonists & inhibitors , Receptor, trkA/antagonists & inhibitors , Time Factors , Tissue Culture Techniques
9.
Cancer Gene Ther ; 14(10): 867-72, 2007 Oct.
Article in English | MEDLINE | ID: mdl-17627293

ABSTRACT

Reovirus type 3 Dearing has demonstrated oncolytic efficacy in vitro and in vivo against a variety of cancer cell lines, tumor xenografts and syngeneic cancer models. In this study, we investigated the effectiveness of reovirus against aberrant crypt foci (ACF) and colon cancer induced by the carcinogen azoxymethane (AOM) in an immunocompetent rat model. Sprague-Dawley rats received 15 mg/kg AOM intraperitoneally once per week for 4 weeks and reovirus was administered rectally once a week for 5 weeks starting 20 weeks after the last dose of AOM. Two weeks after completion of reovirus therapy, animals were examined for tumor burden in the colon and other tissues. Reovirus-treated animals showed a decrease in total ACF numbers (P=0.014), in large ACFs (P=0.0069) and in tumor number (P=0.03) compared to vehicle-treated animals. Fewer obstructing tumors in the colon (P=0.07) and duodenum (P=0.03) and reduced hepatic metastases were also noted. In addition, a tumor cell line derived from hepatic metastases was found to be susceptible to reovirus in vitro. Our results show that repeated rectal reovirus administration had some efficacy in the treatment and prevention of AOM-induced ACFs, colon cancers and metastases.


Subject(s)
Adenocarcinoma/prevention & control , Azoxymethane/toxicity , Carcinogens/toxicity , Colonic Neoplasms/prevention & control , Orthoreovirus/physiology , Precancerous Conditions/prevention & control , Adenocarcinoma/chemically induced , Adenocarcinoma/immunology , Animals , CD8-Positive T-Lymphocytes/cytology , CD8-Positive T-Lymphocytes/immunology , Colonic Neoplasms/chemically induced , Colonic Neoplasms/immunology , Female , Lymphocytes/immunology , Male , Precancerous Conditions/chemically induced , Precancerous Conditions/immunology , Rats , Rats, Sprague-Dawley
10.
Br J Cancer ; 97(3): 302-7, 2007 Aug 06.
Article in English | MEDLINE | ID: mdl-17609661

ABSTRACT

This is one of the few studies that have explored the value of baseline symptoms and health-related quality of life (HRQOL) in predicting survival in brain cancer patients. Baseline HRQOL scores (from the EORTC QLQ-C30 and the Brain Cancer Module (BN 20)) were examined in 490 newly diagnosed glioblastoma cancer patients for the relationship with overall survival by using Cox proportional hazards regression models. Refined techniques as the bootstrap re-sampling procedure and the computation of C-indexes and R(2)-coefficients were used to try and validate the model. Classical analysis controlled for major clinical prognostic factors selected cognitive functioning (P=0.0001), global health status (P=0.0055) and social functioning (P<0.0001) as statistically significant prognostic factors of survival. However, several issues question the validity of these findings. C-indexes and R(2)-coefficients, which are measures of the predictive ability of the models, did not exhibit major improvements when adding selected or all HRQOL scores to clinical factors. While classical techniques lead to positive results, more refined analyses suggest that baseline HRQOL scores add relatively little to clinical factors to predict survival. These results may have implications for future use of HRQOL as a prognostic factor in cancer patients.


Subject(s)
Brain Neoplasms/physiopathology , Glioblastoma/physiopathology , Quality of Life , Survival Analysis , Female , Humans , Male , Middle Aged , Prognosis , Prospective Studies
11.
Curr Oncol ; 14(3): 110-7, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17593983

ABSTRACT

RECOMMENDATION 1: Management of patients with glioblastoma multiforme (GBM) should be highly individualized and should take a multidisciplinary approach involving neuro-oncology, neurosurgery, radiation oncology, and pathology, to optimize treatment outcomes. Patients and caregivers should be kept informed of the progress of treatment at every stage. RECOMMENDATION 2: Sufficient tissue should be obtained during surgery for cytogenetic analysis and, whenever feasible, for tumour banking. RECOMMENDATION 3: Surgery is an integral part of the treatment plan, to establish a histopathologic diagnosis and to achieve safe, maximal, and feasible tumour resection, which may improve clinical signs and symptoms. RECOMMENDATION 4: The preoperative imaging modality of choice is magnetic resonance imaging (MRI) with gadolinium as the contrast agent. Other imaging modalities, such as positron emission tomography with [(18)F]-fluoro-deoxy-d-glucose, may also be considered in selected cases. Postoperative imaging (mri or computed tomography) is recommended within 72 hours of surgery to evaluate the extent of resection. RECOMMENDATION 5: Postoperative external-beam radiotherapy is recommended as standard therapy for patients with gbm. The recommended dose is 60 Gy in 2-Gy fractions. The recommended clinical target volume should be identified with gadolinium-enhanced T1-weighted mri, with a margin in the order of 2-3 cm. Target volumes should be determined based on a postsurgical planning MRI. A shorter course of radiation may be considered for older patients with poor performance status. RECOMMENDATION 6: During RT, temozolomide 75 mg/m(2) should be administered concurrently for the full duration of radio-therapy, typically 42 days. Temozolomide should be given approximately 1 hour before radiation therapy, and at the same time on the days that no radiotherapy is scheduled. RECOMMENDATION 7: Adjuvant temozolomide 150 mg/m(2), in a 5/28-day schedule, is recommended for cycle 1, followed by 5 cycles if well tolerated. Additional cycles may be considered in partial responders. The dose should be increased to 200 mg/m(2) at cycle 2 if well tolerated. Weekly monitoring of blood count is advised during chemoradiation therapy in patients with a low white blood cell count. Pneumocystis carinii pneumonia has been reported, and prophylaxis should be considered. RECOMMENDATION 8: For patients with stable clinical symptoms during combined radiotherapy and temozolomide, completion of 3 cycles of adjuvant therapy is generally advised before a decision is made about whether to continue treatment, because pseudo-progression is a common phenomenon during this time. The recommended duration of therapy is 6 months. A longer duration may be considered in patients who show continuous improvement on therapy. RECOMMENDATION 9: Selected patients with recurrent gbm may be candidates for repeat resection when the situation appears favourable based on an assessment of individual patient factors such as medical history, functional status, and location of the tumour. Entry into a clinical trial is recommended for patients with recurrent disease. RECOMMENDATION 10: The optimal chemotherapeutic strategy for patients who progress following concurrent chemoradiation has not been determined. Therapeutic and clinical-molecular studies with quality of life outcomes are needed.

12.
Oncogene ; 26(28): 4124-34, 2007 Jun 14.
Article in English | MEDLINE | ID: mdl-17213803

ABSTRACT

Reovirus shows considerable potential as an oncolytic agent for Ras-activated tumors and is currently in clinical trials. Here we ask whether such tumor cell lines can acquire resistance to reoviral oncolysis. We challenged human HT1080 fibrosarcoma cells that carry a Ras mutation by prolonged exposure to reovirus, thereby yielding highly virus-resistant HTR1 cells. These cells are persistently infected with reovirus, exhibit high Ras activity and retain the original Ras gene mutation, showing that resistance to reovirus can be displayed in cells with active Ras. The HTR1 cells also exhibit reduced cellular cathepsin B activity, which normally contributes to viral entry and activation. Persistently infected HTR1 cells were not tumorigenic in vivo, whereas immunologically cured virus-free HTR1 cells were highly tumorigenic. Thus, acquisition of resistance to reovirus may constrain therapeutic strategies. To determine whether reoviral resistance is associated with a general reduction in apoptotic potential, we challenged the HTR1 cells with apoptotic inducers and E1B-defective adenovirus, resulting in significant apoptosis and cell death following both approaches. Therefore, even if resistance to reoviral oncolysis should arise in tumor cells in vivo, other therapeutic strategies may nevertheless remain effective.


Subject(s)
Fibrosarcoma/pathology , Oncogene Protein p21(ras)/physiology , Reoviridae/physiology , Base Sequence , Cathepsin B/metabolism , Cell Line , Cell Line, Tumor , DNA Primers , Fibrosarcoma/virology , Humans , Mutation , Oncogene Protein p21(ras)/genetics
13.
Br J Cancer ; 95(8): 1020-7, 2006 Oct 23.
Article in English | MEDLINE | ID: mdl-17047650

ABSTRACT

The use of oncolytic viruses has received considerable attention in recent years and many viruses have proved to be effective against a variety of cancer models and a few are currently being used in clinical trials. However, the possible emergence and outcome of virus-resistant tumour cells has not been addressed. We previously reported the effective use of reovirus against lymphoid malignancies, including the Burkitt's lymphoma cell line Raji. Here we isolated in vitro persistently infected (PI) Raji cells, and cells 'cured' of persistent reovirus infection ('cured' cells). Both PI and cured Raji cells resisted reovirus infection and cell killing in vitro. In vivo, the PI cells were non-tumorigenic in SCID mice, but cured cells regained the parental cells' ability to form tumours. Tumour xenografts from the cured cells, however, were highly susceptible to reovirus oncolysis in vivo. This susceptibility was due to the proteolytic environment within tumours that facilitates reovirus infection and cell killing. Our results show that persistent infection by reovirus impedes tumour development and that although PI cells cleared of reovirus are tumorigenic, they are killed upon rechallenge with reovirus. Both the PI and cured states are therefore not likely to be significant barriers to reovirus oncolytic therapy.


Subject(s)
Burkitt Lymphoma/therapy , Oncolytic Virotherapy , Oncolytic Viruses/physiology , Xenograft Model Antitumor Assays , Animals , Burkitt Lymphoma/pathology , Burkitt Lymphoma/virology , Cell Line, Tumor , Cell Survival/drug effects , Cell Survival/physiology , Cysteine Proteinase Inhibitors/pharmacology , Humans , Leucine/analogs & derivatives , Leucine/pharmacology , Mammalian orthoreovirus 3/drug effects , Mammalian orthoreovirus 3/physiology , Mice , Mice, SCID , Oncolytic Viruses/drug effects , Time Factors , Virion/drug effects , Virion/physiology
14.
J Neurooncol ; 78(3): 311-6, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16710748

ABSTRACT

PURPOSE: To determine the response rate, time to disease progression, survival, and toxicity of intravenous carboplatin and chronic oral high-dose tamoxifen in patients with recurrent malignant gliomas. PATIENTS AND METHODS: Patients with histological confirmation of recurrent malignant gliomas were eligible for this multicenter phase II trial. Treatment consisted of 400 mg/m2 carboplatin intravenously every 4 weeks and oral high dose chronic tamoxifen (80 mg bid in women and 100 mg bid in men). RESULTS: Twenty seven patients met the eligibility criteria and were evaluable for response. The histological subtypes were: 16 (59%) glioblastoma multiforme (GBM), malignant astrocytoma (5 patients), malignant mixed glioma (5 patients), and glioblastoma/gliosarcoma (1 patient). Twenty-two patients (82%) had an ECOG performance status of 0 or 1. No complete responses were observed, 4 patients (15%) achieved a partial response, and 14 patients (52%) had stable disease. Median time to progression was 3.65 months (95%CI 2.56, 4.83). Median overall survival was 14.09 months (95%CI 7.06, 19.91). One patient with a recurrent GBM had a sustained partial response and is progression free 81 months since starting treatment. Another patient with mixed malignant oligoastrocytoma also had a prolonged partial response (lasting 63 months) and is alive 84 months after treatment for recurrence. The most frequently reported grade 3 or 4 toxicities were fatigue (19%), nausea (11%) and anorexia (11%). CONCLUSIONS: Carboplatin and high dose tamoxifen has similar response rates to other regimens for recurrent malignant gliomas and are probably equivalent to those found using tamoxifen as monotherapy. Long-lasting periods of disease free survival in some patients (particularly those with malignant mixed oligo astrocytomas) were found.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Brain Neoplasms/drug therapy , Glioma/drug therapy , Neoplasm Recurrence, Local/drug therapy , Adult , Aged , Anorexia/chemically induced , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Brain Neoplasms/pathology , Carboplatin/administration & dosage , Disease-Free Survival , Dose-Response Relationship, Drug , Drug Administration Schedule , Fatigue/chemically induced , Female , Glioma/pathology , Headache/chemically induced , Humans , Male , Middle Aged , Nausea/chemically induced , Tamoxifen/administration & dosage , Treatment Outcome
15.
Bone Marrow Transplant ; 35(11): 1055-64, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15821774

ABSTRACT

Autologous hematological stem cell transplantation (ASCT) is used for the treatment of many hematological and several solid cancers. ASCT, however, has proven disappointing as a therapeutic strategy for breast cancer. Our group and others have previously shown that breast cancer micrometastases found in patients' apheresis products (APs) predict shorter progression-free and overall survival. The implications of this finding are twofold: (i) contaminating tumor cells (CTCs) in AP reflect a higher systemic disease burden and/or (ii) reinfused CTCs contribute to relapse/progressive disease. To date, purging strategies have been disappointing. We have previously demonstrated the oncolytic properties of reovirus in in vitro, in vivo and ex vivo systems. In the present study, we tested the hypothesis that reovirus purges CTCs in a breast cancer cell line purging model. Reovirus-infected human breast cancer cell lines (HTB 133, HTB 132, SKBR3 and MCF7) exhibited cell death within days. Admixtures of AP with cells from breast tumor cell lines, which were then exposed to reovirus, showed complete purging of CTCs (assessed via flow cytometry/tumor cell outgrowth analysis) without deleterious effect on CD34+ cells. Our results provide preclinical support for the ex vivo use of reovirus as a purging modality for breast cancer during ASCT.


Subject(s)
Bone Marrow Purging/methods , Breast Neoplasms/therapy , Stem Cell Transplantation/methods , Viruses/genetics , Antigens, CD34/biosynthesis , Blood Component Removal , Cell Line, Tumor , DNA Fragmentation , Disease Progression , Disease-Free Survival , Flow Cytometry , Hematopoietic Stem Cells/cytology , Humans , Immunohistochemistry , Immunoprecipitation , Leukocyte Common Antigens/biosynthesis , Methionine/chemistry , Time Factors , Transplantation, Autologous , Treatment Outcome
16.
Gene Ther ; 11(21): 1579-89, 2004 Nov.
Article in English | MEDLINE | ID: mdl-15372068

ABSTRACT

Brain and leptomeningeal metastases are common in breast cancer patients and our current treatments are ineffective. Reovirus type 3 is a replication competent, naturally occurring virus that usurps the activated Ras-signaling pathway (or an element thereof) of tumor cells and lyses them but leaves normal cells relatively unaffected. In this study we evaluated reovirus as an experimental therapeutic in models of central nervous system (CNS) metastasis from breast cancer. We found all breast cancer cell lines tested were susceptible to reovirus, with > 50% of these cells lysed within 72 h of infection. In vivo neurotoxicity studies showed only mild local inflammation at the injection site and mild communicating hydrocephalus with neither diffuse encephalitis nor behavioral abnormalities at the therapeutically effective dose of reovirus (intracranial) (ie 10(7) plaque-forming units) or one dose level higher. In vivo, a single intratumoral administration of reovirus significantly reduced the size of tumors established from two human breast cancer cell lines and significantly prolonged survival. Intrathecal administration of reovirus also remarkably prolonged survival in an immunocompetent racine model of leptomeningeal metastases. These data suggest that the evaluation of reovirus as an experimental therapeutic for CNS metastases from breast cancer is warranted.


Subject(s)
Brain Neoplasms/secondary , Brain Neoplasms/therapy , Breast Neoplasms/therapy , Mammalian orthoreovirus 3 , Reoviridae Infections/complications , Animals , Brain Neoplasms/virology , Cell Death , Cell Line, Tumor , Female , Green Fluorescent Proteins/genetics , Humans , Injections, Intralesional , Lethal Dose 50 , Meningeal Neoplasms/secondary , Meningeal Neoplasms/therapy , Meningeal Neoplasms/virology , Mice , Mice, Nude , Models, Animal , Neoplasms, Experimental , Transfection/methods
17.
J Clin Oncol ; 22(9): 1583-8, 2004 May 01.
Article in English | MEDLINE | ID: mdl-15051755

ABSTRACT

PURPOSE: To prospectively compare standard radiation therapy (RT) with an abbreviated course of RT in older patients with glioblastoma multiforme (GBM). PATIENTS AND METHODS: One hundred patients with GBM, age 60 years or older, were randomly assigned after surgery to receive either standard RT (60 Gy in 30 fractions over 6 weeks) or a shorter course of RT (40 Gy in 15 fractions over 3 weeks). The primary end point was overall survival. The secondary end points were proportionate survival at 6 months, health-related quality of life (HRQoL), and corticosteroid requirement. HRQoL was assessed using the Karnofsky performance status (KPS) and Functional Assessment of Cancer Therapy-Brain (FACT-Br). RESULTS: All patients had died at the time of analysis. Overall survival times measured from randomization were similar at 5.1 months for standard RT versus 5.6 months for the shorter course (log-rank test, P =.57). The survival probabilities at 6 months were also similar at 44.7% for standard RT versus 41.7% for the shorter course (lower-bound 95% CI, -13.7). KPS scores varied markedly but were not significantly different between the two groups (Wilcoxon test, P =.63). Low completion rates of the FACT-Br (45%) precluded meaningful comparisons between the two groups. Of patients completing RT as planned, 49% of patients (standard RT) versus 23% required an increase in posttreatment corticosteroid dosage (chi(2) test, P =.02). CONCLUSION: There is no difference in survival between patients receiving standard RT or short-course RT. In view of the similar KPS scores, decreased increment in corticosteroid requirement, and reduced treatment time, the abbreviated course of RT seems to be a reasonable treatment option for older patients with GBM.


Subject(s)
Brain Neoplasms/radiotherapy , Glioblastoma/radiotherapy , Adrenal Cortex Hormones/therapeutic use , Age Factors , Aged , Brain Neoplasms/pathology , Brain Neoplasms/surgery , Dose Fractionation, Radiation , Female , Glioblastoma/pathology , Glioblastoma/surgery , Humans , Karnofsky Performance Status , Male , Middle Aged , Prospective Studies , Radiotherapy, Adjuvant , Survival Analysis , Treatment Outcome
18.
Bone Marrow Transplant ; 31(8): 679-85, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12692608

ABSTRACT

Treatment of primary central nervous system lymphoma (PCNSL) with combined high-dose methotrexate (HD-MTX)-based chemotherapy and whole-brain radiotherapy (WBRT) is associated with severe neurotoxicity, but high relapse rates are associated with the use of either modality alone. In an attempt to improve upon these dismal results, we treated seven PCNSL patients with HD-MTX-based induction therapy followed by thiotepa, busulfan, cyclophosphamide (TBC), and autologous stem cell transplant (ASCT), without WBRT. Six of these patients had at least one of the following poor prognostic features: Karnofsky performance status (KPS) 60 years, or relapsed disease. All but one patient tolerated the treatment well and experienced improvements in neurological function and overall performance status post-transplant. No treatment-induced neurotoxicity (dementia, ataxia, and incontinence) was observed although the follow-up is short. One early treatment-related death occurred in a patient with multiple comorbid medical conditions. The other six patients achieved a complete response (CR) after TBC and ASCT. Five patients are currently alive and relapse-free at 5, 8, 24, 36, and 42 months from diagnosis. One additional patient relapsed and died 33 months after diagnosis. Two of the seven patients received TBC/ASCT as the only treatment after disease progression following their initial chemotherapy and both remain relapse-free at the time of this report, 22 and 31 months post-TBC/ASCT. In conclusion, prolonged CR can be attained after chemotherapy-only treatment of poor prognosis PCNSL. Furthermore, this small series suggests that high-dose chemotherapy for PCNSL should include drugs that penetrate the CNS such as busulfan and thiotepa rather than standard lymphoma regimens such as BEAM.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Central Nervous System Neoplasms/therapy , Lymphoma/therapy , Stem Cell Transplantation , Adolescent , Adult , Brain/pathology , Brain Neoplasms/radiotherapy , Busulfan/administration & dosage , Central Nervous System Neoplasms/drug therapy , Combined Modality Therapy , Cyclophosphamide/administration & dosage , Female , Follow-Up Studies , Humans , Lymphoma/drug therapy , Magnetic Resonance Imaging , Male , Prognosis , Radiotherapy/adverse effects , Thiotepa/administration & dosage , Transplantation, Homologous , Treatment Outcome
19.
Bone Marrow Transplant ; 30(9): 565-9, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12407430

ABSTRACT

In an attempt to improve the dismal prognosis of adults with recurrent medulloblastoma, six patients were treated with aggressive salvage therapy including high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT). At relapse, all patients underwent surgical debulking followed by HDCT/ASCT and then radiotherapy when possible. The treatment plan included two cycles of HDCT/ASCT; first with cyclophosphamide, etoposide and carboplatin (CECb) and then 2 months later with cyclophosphamide and thiotepa (CT). Three of the six patients received the planned therapy. One patient experienced severe toxicity requiring life-sustaining therapy. This patient developed multi-organ dysfunction including multiple enhancing lesions in both cerebral hemispheres that slowly resolved over several months. Two other patients did not mobilize sufficient stem cells for two ASCT procedures. They received one ASCT conditioned with cyclophosphamide, thiotepa and carboplatin (CTCb). Three of six patients had a complete response (CR); the other three had a partial response (PR). Following the first ASCT, median duration of response was 13.5 months (range 9-29 months) and median survival was 21.5 months (range 12-42 months). There was no treatment-related mortality. We conclude that HDCT/ASCT with CECb-CT or CTCb is active against recurrent medulloblastoma in adults and may be associated with prolonged remissions. Multiple enhancing cerebral lesions on brain MRI early post-HDCT/ASCT may be a consequence of the treatment rather than metastatic disease.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols , Hematopoietic Stem Cell Transplantation , Medulloblastoma/therapy , Salvage Therapy/methods , Adult , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/toxicity , Carboplatin/administration & dosage , Child , Combined Modality Therapy , Cyclophosphamide/administration & dosage , Disease-Free Survival , Etoposide/administration & dosage , Feasibility Studies , Female , Humans , Male , Medulloblastoma/complications , Medulloblastoma/mortality , Radiotherapy, Adjuvant , Recurrence , Remission Induction , Survival Rate , Thiotepa/administration & dosage , Transplantation, Autologous , Treatment Outcome
20.
Neurology ; 59(6): 947-9, 2002 Sep 24.
Article in English | MEDLINE | ID: mdl-12297589

ABSTRACT

The presence of contrast enhancement in a brain tumor is often regarded as a sign of malignancy. The authors identified 314 patients with malignant and low-grade supratentorial glial neoplasms in an unselected population, 58 of which lacked contrast enhancement on preoperative neuroimaging. Nonenhancing gliomas were malignant in approximately one third of cases, especially in older patients. Histologic confirmation of the diagnosis is therefore important in all patients suspected of harboring a primary glial neoplasm.


Subject(s)
Glioma/epidemiology , Glioma/pathology , Supratentorial Neoplasms/epidemiology , Supratentorial Neoplasms/pathology , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Alberta/epidemiology , Child , Child, Preschool , Confidence Intervals , Female , Humans , Infant , Logistic Models , Male , Middle Aged , Retrospective Studies
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