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Dive into the research topics where Timothy C. Kennedy is active.

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Featured researches published by Timothy C. Kennedy.


Journal of Thoracic Oncology | 2009

Detection and Localization of Intraepithelial Neoplasia and Invasive Carcinoma Using Fluorescence-Reflectance Bronchoscopy: An International, Multicenter Clinical Trial

Eric S. Edell; Stephen Lam; Harvey I. Pass; York E. Miller; Thomas G. Sutedja; Timothy C. Kennedy; Gregory M. Loewen; Robert L. Keith

Objectives: The primary objective of this study was to evaluate the benefit of using a new fluorescence-reflectance imaging system, Onco-LIFE, for the detection and localization of intraepitheal neoplasia and early invasive squamous cell carcinoma. A secondary objective was to evaluate the potential use of quantitative image analysis with this device for objective classification of abnormal sites. Design: This study was a prospective, multicenter, comparative, single arm trial. Subjects for this study were aged 45 to 75 years and either current or past smokers of more than 20 pack-years with airflow obstruction, forced expiratory volume in 1 second/forced vital capacity less than 75%, suspected to have lung cancer based on either sputum atypia, abnormal chest roentgenogram/chest computed tomography, or patients with previous curatively treated lung or head and neck cancer within 2 years. Materials and Methods: The primary endpoint of the study was to determine the relative sensitivity of white light bronchoscopy (WLB) plus autofluorescence-reflectance bronchoscopy compared with WLB alone. Bronchoscopy with Onco-LIFE was carried out in two stages. The first stage was performed under white light and mucosal lesions were visually classified. Mucosal lesions were classified using the same scheme in the second stage when viewed with Onco-LIFE in the fluorescence-reflectance mode. All regions classified as suspicious for moderate dysplasia or worse were biopsied, plus at least one nonsuspicious region for control. Specimens were evaluated by the site pathologist and then sent to a reference pathologist, each blinded to the endoscopic findings. Positive lesions were defined as those with moderate/severe dysplasia, carcinoma in situ (CIS), or invasive carcinoma. A positive patient was defined as having at least one lesion of moderate/severe dysplasia, CIS, or invasive carcinoma. Onco-LIFE was also used to quantify the fluorescence-reflectance response (based on the proportion of reflected red light to green fluorescence) for each suspected lesion before biopsy. Results: There were 115 men and 55 women with median age of 62 years. Seven hundred seventy-six biopsy specimens were included. Seventy-six were classified as positive (moderate dysplasia or worse) by pathology. The relative sensitivity on a per-lesion basis of WLB + FLB versus WLB was 1.50 (95% confidence interval [CI], 1.26–1.89). The relative sensitivity on a per-patient basis was 1.33 (95% CI, 1.13–1.70). The relative sensitivity to detect intraepithelial neoplasia (moderate/severe dysplasia or CIS) was 4.29 (95% CI, 2.00–16.00) and 3.50 (95% CI, 1.63–12.00) on a per-lesion and per-patient basis, respectively. For a quantified fluorescence reflectance response value of more than or equal to 0.40, a sensitivity and specificity of 51% and 80%, respectively, could be achieved for detection of moderate/severe dsyplasia, CIS, and microinvasive cancer. Conclusions: Using autofluorescence-reflectance bronchoscopy as an adjunct to WLB with the Onco-LIFE system improves the detection and localization of intraepitheal neoplasia and invasive carcinoma compared with WLB alone. The use of quantitative image analysis to minimize interobserver variation in grading of abnormal sites should be explored further in future prospective clinical trial.


Clinical Cancer Research | 2006

Analysis of c-ErbB1/Epidermal Growth Factor Receptor and c-ErbB2/HER-2 Expression in Bronchial Dysplasia: Evaluation of Potential Targets for Chemoprevention of Lung Cancer

Daniel T. Merrick; John Kittelson; Ralph Winterhalder; Georgia Kotantoulas; Steen Ingeberg; Robert L. Keith; Timothy C. Kennedy; York E. Miller; Wilbur A. Franklin; Fred R. Hirsch

Purpose: Lung cancer is preceded by a premalignant phase during which intervention could decrease associated morbidity and mortality. Molecular characterization of factors involved in controlling progression of bronchial dysplasias will provide markers of premalignant change and identify targets for chemoprevention. Experimental Design: Immunohistochemical analysis of epidermal growth factor receptor (EGFR; c-ErbB1/EGFR), HER-2/neu (c-ErbB2/HER-2), Ki-67, and minichromosome maintenance protein 2 (MCM2) expression in bronchial dysplasia was undertaken to characterize molecular alterations associated with the progression of these lesions in 268 bronchoscopically obtained biopsies from 134 subjects. Results: Analysis of biopsies with the most severe diagnosis from each subject showed a linear relationship between increasing marker expression and severity of dysplastic change for EGFR (P < 0.001), Ki-67 (P < 0.001), and MCM2 (P = 0.001) but not HER-2 (P = 0.102). Increased expression of either EGFR or HER-2 was associated with increased levels of Ki-67 and MCM2 expression, and combined overexpression of these receptors was associated with the highest levels of proliferation, suggesting a synergistic effect. Finally, the lack of an associated trend toward increased EGFR expression when comparing the worst and best biopsies within each subject indicated a potential field effect in the induction of EGFR expression. Conclusions: The results suggest a prominent role for EGFR overexpression in the development and progression of bronchial dysplasia and provide rationale for exploring inhibition of EGFR signaling in lung cancer chemoprevention.


Cancer Prevention Research | 2010

The Detection of Chromosomal Aneusomy by Fluorescence In situ Hybridization in Sputum Predicts Lung Cancer Incidence

Marileila Varella-Garcia; Aline P. Schulte; Holly J. Wolf; William J. Feser; Chan Zeng; Sarah Braudrick; Xiang Yin; Fred R. Hirsch; Timothy C. Kennedy; Robert L. Keith; Anna E. Barón; Steven A. Belinsky; York E. Miller; Tim Byers; Wilbur A. Franklin

Lung cancer usually is disseminated (advanced) and has a poor prognosis at diagnosis. Current and former smokers are at a high risk for lung cancer and are candidates for prevention and early detection strategies. Sputum is a potential source of biomarkers that might determine either lung cancer risk or the presence of early lung cancer, but no current sputum test is sufficiently sensitive and specific for effective screening. We used fluorescence in situ hybridization (FISH) to measure chromosomal aneusomy (CA) in sputum samples collected prospectively from 100 incident lung cancer cases and 96 controls (matched on age, gender, and date of collection) nested within an ongoing high-risk cohort. The CA-FISH assay was aimed at four DNA targets: epidermal growth factor receptor, MYC, 5p15, and CEP 6. The sensitivity of a positive CA-FISH assay (abnormal for two or more of the four markers) for lung cancer was substantially higher for samples collected within 18 months (76% sensitivity) than for samples collected more than 18 months (31%) before lung cancer diagnosis. Sensitivity was higher for squamous cell cancers (94%) than for other histologic types (69%). CA-FISH specificity based on samples collected within 18 months before diagnosis was 88%. The adjusted odds ratio (OR) of lung cancer for specimens collected within 18 months before a cancer diagnosis was higher for the CA-FISH assay [OR, 29.9; 95% confidence interval (95% CI), 9.5-94.1] than for previously studied ORs of cytologic atypia (OR, 1.8; 95% CI, 1.3-2.6) and gene promoter methylation (OR, 6.5; 95% CI, 1.2-35.5). Whether CA-FISH is an indicator of extreme risk for incident lung cancer or detects exfoliated cancer cells is unknown. The apparent promise of CA-FISH in sputum for assessing lung cancer risk and/or for lung cancer early detection now needs to be validated in a clinical screening trial. Cancer Prev Res; 3(4); 447–53. ©2010 AACR.


Cancer | 1983

Unexplained pulmonary infiltrates in the compromised patient an invasive investigation in a consecutive series

Edward M. Canham; Timothy C. Kennedy; Thomas A. Merrick

A series of 51 consecutive unexplained pulmonary infiltrates were reviewed retrospectively, in a group of 48 patients in whom invasive procedures were performed. Fifty‐two percent of these patients had leukemia or lymphoma and 40% had solid tumors. All patients had lung tissue obtained premortem either by transbronchial biopsy through the flexible fiberoptic bronchoscope or by open lung biopsy. There was a 27% complication rate in these invasive procedures including bleeding, pneumothorax, and ventilatory support. Infectious agents were found in only 13 cases (25%) with a mortality rate of 62%. The pathologic finding of the underlying malignant disease or organizing pneumonia portended a poor prognosis with 100% and 80% mortality, respectively. Twenty‐one patients had biopsy tissue revealing only nonspecific pathologic changes and were associated with the lowest mortality (19%). It was found that 50% of the solid tumor patients with unexplained pulmonary infiltrates had nonspecific pathologic changes. The biopsy findings resulted in a change in the therapy in 29% of the cases and in 19% of the cases the subsequent change in therapy resulted in marked improvement. The lung biopsy is useful to diagnose treatable infectious disease, as well as for prognostic guidance in caring for critically ill compromised patients. Cancer 52:325‐329, 1983.


Cancer Epidemiology, Biomarkers & Prevention | 2007

Bronchial Epithelial Ki-67 Index Is Related to Histology, Smoking, and Gender, but Not Lung Cancer or Chronic Obstructive Pulmonary Disease

York E. Miller; Patrick J. Blatchford; Dae Sung Hyun; Robert L. Keith; Timothy C. Kennedy; Holly J. Wolf; Tim Byers; Paul A. Bunn; Marina T. Lewis; Wilbur A. Franklin; Fred R. Hirsch; John Kittelson

Purpose: To determine whether increased bronchial epithelial proliferation is associated with histology, smoking status, gender, age, chronic obstructive pulmonary disease (COPD), or lung cancer. Experimental Design: Cross-sectional study of 113 subjects undergoing white light and autofluorescence bronchoscopy: 27 never smokers; 27 current or ex-smokers with normal spirometry; 31 current or ex-smokers with COPD; and 28 current, ex-, or never smokers with lung cancer. Ki-67 expresssion was determined by immunohistochemistry on all evaluable biopsy sites without carcinoma. Relationships between Ki-67 index (percentage of epithelial cells expressing Ki-67), demographic variables, smoking, histology, and the presence of COPD and/or lung cancer were determined. Results: Results for both maximal and mean Ki-67 index are similar, so only the former are reported. Average maximal Ki-67 index was higher in current smokers than either ex-smokers or never smokers (48.0% versus 30.6% versus 22.6%; P < 0.001). Males had higher Ki-67 index than females (39.9% versus 23.6%; P < 0.001). Compared with subjects without disease (Ki-67 index = 30.0%), maximal Ki-67 index was not significantly elevated (P = 0.44) in subjects with either lung cancer (Ki-67 = 39.1%) or COPD (Ki-67 = 38.9%). Conclusions: Smoking status, bronchial histology, and gender were significantly associated with Ki-67 index. No increase in Ki-67 index was found in the nonmalignant epithelium of patients with lung cancer or COPD. Although Ki-67 index may provide insight into the short-term effects of chemoprevention agents on cell proliferation, its lack of association with lung cancer or COPD raises question regarding its utility as a lung cancer risk biomarker. (Cancer Epidemiol Biomarkers Prev 2007;16(11):2425–31)


Cancer Epidemiology, Biomarkers & Prevention | 2008

Sputum Cytologic Atypia Predicts Incident Lung Cancer: Defining Latency and Histologic Specificity

Tim Byers; Holly J. Wolf; Wilbur A. Franklin; Sarah Braudrick; Daniel T. Merrick; Kenneth R. Shroyer; Fred R. Hirsch; Chan Zeng; Anna E. Barón; Paul A. Bunn; York E. Miller; Timothy C. Kennedy

Background: There is a need for early detection methods for lung cancer. Radiologic imaging may be more sensitive for peripheral cancers than for cancers arising in the central airways, from which bronchial epithelial cells are exfoliated into the sputum. Methods: Sputum samples were collected at baseline and periodically thereafter in a cohort of smokers and former smokers with chronic obstructive lung disease. The association between cytologic atypia and incident lung cancer was assessed by hazard ratios (HR; 95% confidence intervals) using Cox regression and by odds ratios (95% confidence intervals) using logistic regression, adjusting for potential confounding factors. Results: We observed 174 incident lung cancers in a cohort of 2,521 people over 9,869 person-years of observation. Risk for incident lung cancer was increased among those with cytologic atypia graded as moderate or worse (adjusted HR, 2.37; 1.68-3.34). The association between sputum atypia and lung cancer incidence was greatest for those sputum samples collected 5 months or less before the diagnosis of lung cancer (odds ratio, 10.32; 5.34-19.97). The association was substantially stronger for squamous cell lung cancers (HR, 5.13; 2.89-9.10) than for adenocarcinomas (HR, 1.85; 0.94-3.65). Conclusion: Cytologic atypia is a marker for increased lung cancer risk. These cytologic changes seem to arise from late events that are most apparent for cancers arising in the central respiratory airways. Whether cytologic atypia might complement radiologic imaging in a combined approach to lung cancer, early detection requires additional evaluation of those two methods used together. (Cancer Epidemiol Biomarkers Prev 2008;17(1):158–63)


Cancer Prevention Research | 2016

Persistence of Bronchial Dysplasia Is Associated with Development of Invasive Squamous Cell Carcinoma.

Daniel T. Merrick; Dexiang Gao; York E. Miller; Robert L. Keith; Anna E. Barón; William Feser; Timothy C. Kennedy; Patrick J. Blatchford; Sarah Braudrick; Fred R. Hirsch; Lynn E. Heasley; Paul A. Bunn; Wilbur A. Franklin

Bronchial dysplasia (BD), a presumed precursor of pulmonary squamous cell carcinoma (SCC), rarely progresses to invasive cancer. A high-risk cohort at the University of Colorado provided an opportunity to directly sample airway epithelium at mapped sites on successive bronchoscopies. We have hypothesized that persistent dysplastic lesions showing a similar or higher level of dysplasia on follow-up biopsy, are associated with increased risk for the development of SCC. Endoscopic biopsies from 188 high-risk subjects were histologically classified according to the current WHO classification for BD using a numeric histology score ranging from 1 to 8 representing normal bronchial mucosa through invasive lung cancer. Differences in follow-up histology scores were compared between sites classified by clinical, histologic, and immunohistochemical variables. Subjects with a higher frequency of sites that persist or progress to high-grade dysplasia (≥37.5% persist/progress, N = 35 versus <37.5% persist/progress, N = 114) show a significant association with development of incident invasive SCC (adjusted HR, 7.84; 95% confidence interval, 1.56–39.39), and those with incident lung SCC have adjusted mean follow-up histology scores 1.55 U higher than in subjects without lung cancer. Current smoking, elevated Ki67 growth fraction, histologic features of angiogenic squamous dysplasia (ASD) and higher histology score in baseline biopsies are significantly associated with increased follow-up histology scores. These results show that persistent BD is associated with the development of invasive SCC. Furthermore, increased expression of Ki67, the presence of angiogenic change and degree of baseline atypia are associated with persistence of BD. Cancer Prev Res; 9(1); 96–104. ©2015 AACR.


Lung Cancer | 1997

613 Homozygous deletions of human chromosome 3p in lung tumors

S. Todd; Wilbur A. Franklin; Marileila Varella-Garcia; Timothy C. Kennedy; C.E. Hilliker; L. Hahner; M.W. Anderson; J.S. Wiest; Harry A. Drabkin; Robert M. Gemmill

Cytogenetic and loss of heterozygosity (LOH) studies have demonstrated that deletions of chromosome 3p occur at a high frequency in all forms of lung cancer. To clarify the role of 3p in lung tumorigenesis and to more precisely identify targets for positional cloning efforts, we have performed 3p deletion analyses (microsatellite and fluorescence in situ hybridization) in a series of lung cancer cell lines and uncultured tumor samples. Importantly, we identified homozygous deletions in four uncultured tumors and one cell line. Homozygous deletions were found in three squamous tumors within a region of 3p21 which had previously been described only in cell lines, a 1-2-megabase homozygous deletion in a small cell tumor at 3p12, and a 3p14.2 homozygous deletion in a non-small cell lung carcinoma cell line. The detection of homozygous deletions affecting these multiple regions in uncultured tumor cells substantiates the belief (previously based on deletions found only in tumor cell lines) that these sites contain important tumor suppressor genes. Along with previously reported homozygous deletions in a distal portion of 3p21.3, we now have evidence for four separate regions of 3p which undergo homozygous deletions in either uncultured lung tumors or cell lines.


Cancer Research | 2018

Altered Cell-Cycle Control, Inflammation, and Adhesion in High-Risk Persistent Bronchial Dysplasia

Daniel T. Merrick; Michael G. Edwards; Wilbur A. Franklin; Michio Sugita; Robert L. Keith; York E. Miller; Micah Friedman; Lori D. Dwyer-Nield; Meredith A. Tennis; Mary C. O'Keefe; Elizabeth J. Donald; Jessica M. Malloy; Adrie van Bokhoven; Storey Wilson; Peter J. Koch; Charlene O'Shea; Christopher D. Coldren; David J. Orlicky; Xian Lu; Anna E. Barón; Greg Hickey; Timothy C. Kennedy; Roger L. Powell; Lynn E. Heasley; Paul A. Bunn; Mark Geraci; Raphael A. Nemenoff

Persistent bronchial dysplasia is associated with increased risk of developing invasive squamous cell carcinoma (SCC) of the lung. In this study, we hypothesized that differences in gene expression profiles between persistent and regressive bronchial dysplasia would identify cellular processes that underlie progression to SCC. RNA expression arrays comparing baseline biopsies from 32 bronchial sites that persisted/progressed to 31 regressive sites showed 395 differentially expressed genes [ANOVA, FDR ≤ 0.05). Thirty-one pathways showed significantly altered activity between the two groups, many of which were associated with cell-cycle control and proliferation, inflammation, or epithelial differentiation/cell-cell adhesion. Cultured persistent bronchial dysplasia cells exhibited increased expression of Polo-like kinase 1 (PLK1), which was associated with multiple cell-cycle pathways. Treatment with PLK1 inhibitor induced apoptosis and G2-M arrest and decreased proliferation compared with untreated cells; these effects were not seen in normal or regressive bronchial dysplasia cultures. Inflammatory pathway activity was decreased in persistent bronchial dysplasia, and the presence of an inflammatory infiltrate was more common in regressive bronchial dysplasia. Regressive bronchial dysplasia was also associated with trends toward overall increases in macrophages and T lymphocytes and altered polarization of these inflammatory cell subsets. Increased desmoglein 3 and plakoglobin expression was associated with higher grade and persistence of bronchial dysplasia. These results identify alterations in the persistent subset of bronchial dysplasia that are associated with high risk for progression to invasive SCC. These alterations may serve as strong markers of risk and as effective targets for lung cancer prevention.Significance: Gene expression profiling of high-risk persistent bronchial dysplasia reveals changes in cell-cycle control, inflammatory activity, and epithelial differentiation/cell-cell adhesion that may underlie progression to invasive SCC. Cancer Res; 78(17); 4971-83. ©2018 AACR.


Proceedings IMCS 2012 | 2012

7.1.1 Invited: Chemical Nanoarrays for Early Detection and Screening of Lung Cancer via Volatile Biomarkers

Hossam Haick; Orna Barash; Meggie Hakim; Ulrike Tisch; Radu Ionescu; P. A. Bunn; Jane Mattei; York E. Miller; Timothy C. Kennedy; John D. Mitchell; Michael J. Weyant; Fred R. Hirsch; N. Peled; Maya Ilouze

Lung cancer is the leading cause of cancer-related deaths worldwide. The cancer’s stage, histology and genetic mutations determine a patient’s prognosis and treatment. Here we present an artificial electronic nose (NA-NOSE), which makes use of cross-reactive chemical sensor nanoarrays, for the detection of volatile biomarkers in breath samples as well as in the headspace of in-vitro cell lines of lung cancer. A series of proof-of-concept studies with the NA-NOSE have shown an excellent ability to distinguish between lung cancer and healthy states, between different histologies of link cancer, and between lung cancer genetic mutations that can benefit from targeted treatments. The proposed biomarker-based testing NA-NOSE technology holds future potential as a cost-effective, fast and reliable diagnostic test for early disease detection and monitoring of the disease progression. The NANOSE would be suitable for use outside of specialist settings and could significantly reduce in the burden on the health budget.

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York E. Miller

University of Colorado Denver

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Fred R. Hirsch

University of Colorado Denver

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Robert L. Keith

University of Colorado Denver

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Paul A. Bunn

University of Colorado Denver

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Tim Byers

University of Colorado Denver

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Daniel T. Merrick

University of Colorado Denver

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Holly J. Wolf

University of Colorado Denver

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