Jean LeRiche
University of British Columbia
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The Journal of Allergy and Clinical Immunology | 1988
Stephen Lam; Henry Chan; Jean LeRiche; Moira Chan-Yeung; Hassan Salari
To investigate whether leukotrienes (LTs) are released into the bronchial fluid of patients with symptomatic asthma, bronchial lavage was carried out in 17 patients with mild to severe asthma and nine healthy subjects without asthma. LTE4 was detected in 15 of the 17 patients with asthma with reverse-phase high-performance liquid chromatography. The identify of LTE4 was confirmed by ultraviolet spectrometry and by positive ion fast atom-bombardment mass spectrometry. LTD4 was found in two patients and 20-OH-LTB4 in 12 patients. No LTs were detectable in the lavage fluid from any of the healthy subjects without asthma. The finding of LTs in bronchial lavage fluid from the patients with asthma despite bronchodilator and/or corticosteroid therapy suggests that these compounds may be important in asthma. However, the presence of significant quantities of LTE4 in patients with mild asthma requiring only intermittent bronchodilator therapy for control and the lack of correlation between LTE4 and pulmonary function also suggests that other factors may be important in determining the net end organ response. The present study points to the importance of studying the whole spectrum of mediators that are released. Analysis of bronchial lavage fluid may be useful in determining the relative role of these mediators and the effect of pharmacologic intervention.
Clinical Cancer Research | 2008
Stephen Lam; Beau A. Standish; Corisande Baldwin; Annette McWilliams; Jean LeRiche; Adi F. Gazdar; Alex Vitkin; Victor X. D. Yang; Norihiko Ikeda; Calum MacAulay
Purpose: Optical coherence tomography (OCT) is an optical imaging method that can visualize cellular and extracellular structures at and below tissue surface. The objective of the study was to determine if OCT could characterize preneoplastic changes in the bronchial epithelium identified by autofluorescence bronchoscopy. Experimental Design: A 1.5-mm fiberoptic probe was inserted via a bronchoscope into the airways of 138 volunteer heavy smokers participating in a chemoprevention trial and 10 patients with lung cancer to evaluate areas that were found to be normal or abnormal on autofluorescence bronchoscopy. Radial scanning of the airways was done to generate OCT images in real time. Following OCT imaging, the same sites were biopsied for pathologic correlation. Results: A total of 281 OCT images and the corresponding bronchial biopsies were obtained. The histopathology of these areas includes 145 normal/hyperplasia, 61 metaplasia, 39 mild dysplasia, 10 moderate dysplasia, 6 severe dysplasia, 7 carcinoma in situ, and 13 invasive carcinomas. Quantitative measurement of the epithelial thickness showed that invasive carcinoma was significantly different than carcinoma in situ (P = 0.004) and dysplasia was significantly different than metaplasia or hyperplasia (P = 0.002). In addition, nuclei of the cells corresponding to histologic results became more discernible in lesions that were moderate dysplasia or worse compared with lower-grade lesions. Conclusion: Preliminary data suggest that autofluorescence bronchoscopy–guided OCT imaging of bronchial lesions is technically feasible. OCT may be a promising nonbiopsy tool for in vivo imaging of preneoplastic bronchial lesions to study their natural history and the effect of chemopreventive intervention.
The Journal of Allergy and Clinical Immunology | 1987
Stephen Lam; Jean LeRiche; D. Phillips; M. Chan-Young
To investigate the sequence of cellular and protein changes after a late asthmatic reaction (LAR), bronchial lavage was carried out in 44 patients with red cedar asthma at different time intervals after bronchial challenge with plicatic acid. The results were compared to five patients with red cedar asthma who became asymptomatic after removal from exposure to red cedar for more than 2 months and 31 healthy subjects without asthma. The LAR was found to be associated with an increase in eosinophils in the lavage fluid, an increase in sloughing of bronchial epithelial cells, and an increase in degenerated cells consisting mainly of degenerated epithelial cells and alveolar macrophages. There was an increase in vascular permeability as reflected by an increase in albumin in the lavage fluid. Although there was a slight but significant increase in neutrophils 48 hours after bronchial challenge, neutrophil infiltration was not a prominent feature earlier. The potential role of loss of epithelial cells to account for an increase in nonspecific bronchial hyperresponsiveness after an LAR was discussed.
Clinical Cancer Research | 2004
Stephen Lam; Jean LeRiche; Annette McWilliams; Calum MacAulay; Yulia D'yachkova; Eva Szabo; John R. Mayo; R. Robert Schellenberg; Andy Coldman; Ernest T. Hawk; Adi F. Gazdar
Purpose: Preclinical studies suggest that inhaled budesonide may be an effective chemopreventive agent for lung cancer. We conducted a phase IIb study to determine the effects of inhaled budesonide in smokers with bronchial dysplasia. Experimental Design: A total of 112 smokers with more than or equal to one site of bronchial dysplasia > 1.2 mm in size identified by autofluorescence bronchoscopy-directed biopsy was randomly assigned to receive placebo or budesonide (Pulmicort Turbuhaler) 800 μg twice daily inhalation for 6 months. The primary end point was change in the histopathologic grade on repeat biopsy of the same sites at the end of 6 months. Results: There were no significant differences in the regression or progression rates of bronchial dysplasia between the two groups. There was a statistically significant but modest decrease in p53 and BclII expression in the bronchial biopsies after 6 months of Pulmicort Turbuhaler versus placebo (P = 0.01 and P = 0.001, respectively). There was a small but statistically significant decrease in the proportion of computed tomography-detected lung nodules after Pulmicort Turbuhaler compared with placebo (P = 0.024). Conclusions: Our results suggest that in smokers, inhaled budesonide in the dose of 1600 μg daily for 6 months had no effect in regression of bronchial dysplastic lesions or prevention of new lesions. Budesonide treatment resulted in a modest decrease in p53 and BclII protein expression in bronchial biopsies and a slightly higher rate of resolution of computed tomography-detected lung nodules. Whether budesonide truly has an effect in preneoplastic lesions in the peripheral airways and alveoli requires additional investigation.
Diagnostic and Therapeutic Endoscopy | 1994
Stephen Lam; Calum MacAulay; Jean LeRiche; Norihiko Ikeda; Branko Palcic
The performance of a fluorescence imaging device was compared with conventional white-light bronchoscopy in 100 patients with lung cancer, 46 patients with resected stage I non-small cell lung cancer, 10 patients with head and neck cancer, and 67 volunteers who had smoked at least 1 pack of cigarettes per day for 25 years or more. Using differences in tissue autofluorescence between premalignant, malignant, and normal tissues, fluorescence bronchoscopy was found to detect significantly more areas with moderate/severe dysplasia or carcinoma in situ than conventional white-light bronchoscopy with a similar specificity. Multiple foci of dysplasia or cancer were found in 13–24% of these individuals. Fluorescence bronchoscopy may be an important adjunct to conventional bronchoscopic examination to improve our ability to detect and localize premalignant and early lung cancer lesions.
Cancer Epidemiology, Biomarkers & Prevention | 2006
Stephen Lam; Annette McWilliams; Jean LeRiche; Calum MacAulay; Lee W. Wattenberg; Eva Szabo
Introduction: A phase I, open-label, multiple dose, dose-escalation clinical study was conducted to assess the safety, tolerability, maximum tolerated dose, and potential chemopreventive effect of myo-inositol in smokers with bronchial dysplasia. Materials and Methods: Smokers between 40 and 74 years of age with ≥ 30 pack-years of smoking history and one or more sites of bronchial dysplasia were enrolled. A dose escalation study ranging from 12 to 30 g/d of myo-inositol for a month was first conducted in 16 subjects to determine the maximum tolerated dose. Ten new subjects were then enrolled to take the maximum tolerated dose for 3 months. The potential chemopreventive effect of myo-inositol was estimated by repeat autofluorescence bronchoscopy and biopsy. Results: The maximum tolerated dose was found to be 18 g/d. Side effects, when present, were mild and mainly gastrointestinal in nature. Using the regression rate of the placebo subjects from a recently completed clinical trial with the same inclusion/exclusion criteria as a comparison, a significant increase in the rate of regression of preexisting dysplastic lesions was observed (91% versus 48%; P = 0.014). A statistically significant reduction in the systolic and diastolic blood pressures by an average of 10 mm Hg was observed after taking 18 g/d of myo-inositol for a month or more. Conclusion: myo-Inositol in a daily dose of 18 g p.o. for 3 months is safe and well tolerated. The potential chemopreventive effect as well as other health benefits such as reduction in blood pressure should be investigated further. (Cancer Epidemiol Biomarkers Prev 2006;15(8):1526–31)
Clinical Cancer Research | 2006
Jean-Claude Cutz; Jun Guan; Jane Bayani; Maisa Yoshimoto; Hui Xue; Margaret Sutcliffe; John C. English; Julia Flint; Jean LeRiche; John Yee; Jeremy A. Squire; Peter W. Gout; Stephen Lam; Yuzhuo Wang
Purpose: Lung cancer is a biologically diverse disease and relevant models reflecting its diversity would facilitate the improvement of existing therapies. With a view to establishing such models, we developed and evaluated xenografts of a variety of human lung cancers. Experimental Design: Using nonobese diabetic/severe combined immunodeficiency mice, subrenal capsule xenografts were generated from primary lung cancer tissue, including moderately and poorly differentiated squamous cell carcinoma, adenocarcinoma, adenosquamous carcinoma, small cell carcinoma, large cell undifferentiated carcinoma, and carcinosarcoma. After 4 to 12 weeks, xenografts were harvested for serial transplantation and comparison with the original tissue via histologic, chromosomal, and cytogenetic analyses. Results: Xenografts were successfully established. H&E staining showed that xenografts retained major histologic features of the original cancers. Immunohistochemistry and fluorescence in situ hybridization confirmed the human origin of the tumor cells and development in xenografts of murine supportive stroma. Four transplantable lines were developed from rapidly growing tumors (>5 generations), i.e., a small cell lung carcinoma, large cell undifferentiated carcinoma, pulmonary carcinosarcoma, and squamous cell carcinoma. Analyses including spectral karyotyping, comparative genomic hybridization, and fluorescence in situ hybridization, revealed that the xenografts were genetically similar to the original tumors, showing chromosomal abnormalities consistent with karyotypic changes reported for lung cancer. Conclusions: The subrenal capsule xenograft approach essentially provides a living tumor bank derived from patient material and a means for isolating and expanding specific cell populations. The transplantable tumor lines seem to provide good models for studying various aspects of tumor progression and a platform for developing novel therapeutic regimens, with the possibility of patient-tailored therapies.
Mayo Clinic Proceedings | 1997
Peter William Payne; Thomas J Sebo; Alexi Doudkine; David Garner; Calum Vancouver Macaulay; Stephen Lam; Jean LeRiche; Branko M. Palcic
OBJECTIVE To investigate the hypothesis that image cytometry of sputum specimens can detect squamous carcinoma without requiring visually abnormal cells. DESIGN The sensitivity and specificity of image cytometry were evaluated in a case-control study. MATERIAL AND METHODS Seventy-three sputum slides from the Mayo portion of the National Cancer Institute Cooperative Early Lung Cancer Study were restained by a modified Feulgen method. We examined 40 slides from 9 patients in whom squamous carcinoma developed and 33 slides from 11 patients in whom no cancer developed during a follow-up of at least 5 years. Images of normal epithelial nuclei were collected by using an automated image cytometer. Discriminant analysis was used to determine differences in DNA distribution of normal nuclei in sputum specimens from noncancer patients versus normal nuclei in sputum samples from patients in whom carcinoma developed. RESULTS By using features based on DNA distribution, 74% correct classification of nuclei was possible without human review of the material and without the use of visually abnormal nuclei. A receiver operating characteristic curve demonstrated sensitivities and specificities, including 40% sensitivity and 90% specificity. CONCLUSION Although this study was limited to 20-year-old slides and squamous cell carcinoma, automated image cytometry detected a substantial proportion of patients with squamous cell cancer without using visually abnormal nuclei.
Journal of Bronchology | 1994
Tom G. Sutedja; Stephen Lam; Jean LeRiche; Pieter E. Postmus
AbstractPhotodynamic therapy (PDT) causes selective tumor damage and has been shown to be effective in the treatment of early-stage lung cancer. Thirty patients, with 39 intraluminal cancer lesions, who were considered to be high-risk surgical candidates, were treated with PDT. A complete response a
Lung Cancer | 1998
Norihiko Ikeda; Calum MacAulay; Stephen Lam; Jean LeRiche; Peter William Payne; David Garner; Chimori Konaka; Harubumi Kato; Branko Palcic
A total of 74 bronchial brushing specimens, 24 from patients with advanced stage cancer, eight from patients with CIS, 31 from patients with atypical metaplasia and 11 from normal subjects were examined for the existence of malignancy associated changes (MAC). Conventional fiberoptic bronchoscopy and fluorescence endoscopy was carried out on every case. Each case was classified according to the highest grade of abnormality diagnosed by bronchial biopsy of the suspect areas. During the endoscopy examination, a bronchial brushing specimen was obtained from a visually normal area very remote from the abnormal area as possible such as the opposite lung or another lobe. The bronchial brushing specimens were fixed, mounted and stained by a DNA specific method and approximately 1500 images of individual nuclei per case were captured by an automated high resolution image cytometry. For each of these images, more than 100 nuclear features such as size, shape and chromatin spatial organization were calculated. Discriminant function analysis revealed nuclear features which differentiated between normal bronchial cell nuclei from the normal subjects and ostensively normal nuclei (MAC cell nuclei) from the lung cancer patients. The best discrimination was achieved when the frequency of individual cells expressing MAC was 50% or greater. With this threshold, 75% of the patients with invasive cancer and CIS were correctly classified. Fifty percent of those with severe or moderate atypia and 35% with mild atypia were also MAC positive. The frequency of cells expressing MAC also increased as the degree of abnormality of the groups increased. MAC may be a useful criterium to determine biological behavior of the intra-epithelial (pre-invasive) neoplasia.
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University of Texas Health Science Center at San Antonio
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