33 results on '"Trask DK"'
Search Results
2. Expression of Bcl-2 family proteins in advanced laryngeal squamous cell carcinoma: correlation with response to chemotherapy and organ preservation.
- Author
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Trask DK, Wolf GT, Bradford CR, Fisher SG, Devaney K, Johnson M, Singleton T, and Wicha M
- Published
- 2002
3. Medicare volume and reimbursement trends in lingual and hyoid procedures for obstructive sleep apnea.
- Author
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Torabi SJ, Tsang C, Patel RA, Nguyen TV, Manes RP, Kuan EC, and Trask DK
- Subjects
- Humans, United States, Retrospective Studies, Medicare economics, Insurance, Health, Reimbursement trends, Insurance, Health, Reimbursement economics, Sleep Apnea, Obstructive surgery, Sleep Apnea, Obstructive economics, Hyoid Bone surgery, Tongue surgery
- Abstract
Objectives: This study aims to analyze utilization and reimbursement trends in lingual and hyoid surgery for obstructive sleep apnea (OSA)., Methods: Annual retrospective data on lingual and hyoid OSA surgeries was obtained from the 2000-2021 Medicare Part B National Summary Datafiles. Current Procedural Terminology (CPT) codes utilized included 21,685 (hyoid myotomy and suspension [HMS]), 41,512 (tongue base suspension [TBS]), 41,530 (radiofrequency ablation of the tongue [RFT]) and 42,870 (lingual tonsillectomy [LT])., Results: The number of lingual and hyoid OSA surgeries rose 2777 % from 121 in 2000 to 3481 in 2015, before falling 82.9 % to 594 in 2021. Accordingly, Medicare payments rose 17,899 % from an inflation-adjusted $46,958 in 2000 to $8.45 million in 2015, before falling drastically to $341,011 in 2021. As the number of HMSs (2000: 91; 2015: 84; 2021: 165), TBS (2009: 48; 2015: 31; 2021: 16), and LTs (2000: 121; 2015: 261; 2021: 234) only experienced modest changes in utilization, this change was largely driven by RFT (2009: 340; 2015: 3105; 2021: 179). Average Medicare payments for RFT rose from $1110 in 2009 to $2994 in 2015, before falling drastically to $737 in 2021., Conclusion: Lingual and hyoid surgery for OSA has overall fallen in utilization among the Medicare population from 2000 to 2021. However, there was a brief spike in usage, peaking in 2015, driven by the adoption (and then quick dismissal) of RFT. The rise and fall in RFT use coincide with the rise and fall in reimbursement., (Copyright © 2024 Elsevier Inc. All rights reserved.)
- Published
- 2024
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4. Preoperative Predictors of Response to Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea.
- Author
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Xiao R, Trask DK, and Kominsky AH
- Subjects
- Aged, Female, Humans, Male, Middle Aged, Polysomnography, Retrospective Studies, Sleep Apnea, Obstructive physiopathology, Tongue innervation, Electric Stimulation Therapy, Hypoglossal Nerve, Sleep Apnea, Obstructive therapy
- Abstract
Objective: Hypoglossal nerve stimulation (HGNS) is an effective treatment for patients with obstructive sleep apnea (OSA) who fail continuous positive airway pressure (CPAP). We assessed the relationship between patient characteristics and response to HGNS., Study Design: Retrospective cohort study., Setting: Single tertiary care institution., Subjects and Methods: This study included CPAP-intolerant patients with moderate to severe OSA after HGNS system implantation from November 2015 to December 2017. Patient measures, drug-induced sleep endoscopy (DISE) findings, and apnea-hypopnea indices (AHIs) were recorded., Results: Forty-eight patients underwent implantation with the following median measures: age, 66 years; body mass index, 28.6; and neck circumference, 41.0 cm. Patients were classified by Friedman tongue position (II, 27%; III, 56%; IV, 17%) and Mallampati grade (I, 25%; II, 50%; III, 23%; IV, 2%). By DISE, 71% had anterior-posterior palatal collapse. Additionally, 38% had lateral oropharynx collapse; 50%, tongue base collapse; and 27%, epiglottis collapse. Following implantation, median AHI improved from 38.5 to 2.7 ( P < .001), and 92% of patients had no worse than mild OSA (8% moderate). Patients with Friedman tongue position grade II/III experienced greater change in AHI as compared with grade IV (94.2% vs 73.8%, P < .001). Patients with Mallampati score I/II experienced greater improvement versus score III/IV (94.7% vs 66.5%, P < .001). No DISE findings, including any obstruction or collapse, were associated with change in AHI., Conclusion: This study further confirms HGNS as an effective treatment of CPAP-intolerant OSA. Office measures such as Friedman tongue position IV and Mallampati III/IV were associated with mildly decreased response. DISE findings were not associated with patient response.
- Published
- 2020
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5. Voice and swallowing outcomes following hypoglossal nerve stimulation for obstructive sleep apnea.
- Author
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Bowen AJ, Nowacki AS, Kominsky AH, Trask DK, Benninger MS, and Bryson PC
- Subjects
- Adult, Aged, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prospective Studies, Sleep Apnea, Obstructive physiopathology, Surveys and Questionnaires, Treatment Outcome, Deglutition physiology, Electric Stimulation Therapy methods, Hypoglossal Nerve physiopathology, Sleep Apnea, Obstructive surgery, Voice physiology
- Abstract
Objective: Hypoglossal nerve stimulation is an effective treatment for a subset of patients with Obstructive Sleep Apnea (OSA). Although multiple clinical trials demonstrate its efficacy, no previous literature explores the potential impact the stimulator has on swallowing and voice. Our primary objective is to evaluate patient reported post-operative changes in voice or swallowing following hypoglossal nerve stimulator placement., Study Design: Prospective cohort study., Setting: Tertiary care hospital., Subject and Methods: Patients scheduled to receive a hypoglossal stimulator were enrolled. Participants completed baseline Voice Handicap Index-10 (VHI-10) and Eating Assessment Tool-10 (EAT-10) questionnaires preoperatively and again at 1week, 3months, and 6months post-operatively following placement of a hypoglossal nerve stimulator., Results: 9 males and 5 females completed the study. The mean pre-operative VHI-10 and EAT-10 score was 3 and 0.8 respectively. Using linear mixed models, a clinically and statistically significant increase in the mean EAT-10 score was observed post-operatively at 1week (p=0.007), which was not observed at the time points the stimulator was active. A clinically and statistically significant decrease in VHI-10 score was observed following 2months of active stimulator use (p=0.02), which was not observed at any other time point., Conclusion: The implantation and use of the hypoglossal nerve stimulator over 5months did not demonstrate any sustained, patient reported changes in voice handicap and swallowing function. While larger studies are warranted, our findings can be used to provide further informed consent for hypoglossal nerve stimulator implantation., (Copyright © 2017 Elsevier Inc. All rights reserved.)
- Published
- 2018
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6. Celecoxib Versus Placebo in Tonsillectomy: A Prospective, Randomized, Double-Blind Placebo-Controlled Trial.
- Author
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Van Daele DJ, Bodeker KL, and Trask DK
- Subjects
- Acetaminophen therapeutic use, Adult, Analgesics, Non-Narcotic therapeutic use, Analgesics, Opioid therapeutic use, Chronic Disease, Double-Blind Method, Drug Combinations, Female, Humans, Hydrocodone therapeutic use, Male, Pain Management, Pain Measurement, Prospective Studies, Recurrence, Young Adult, Celecoxib therapeutic use, Cyclooxygenase 2 Inhibitors therapeutic use, Pain, Postoperative drug therapy, Tonsillectomy, Tonsillitis surgery
- Abstract
Objectives: Celecoxib is a cyclooxygenase-2-specific inhibitor indicated to treat acute pain and pain secondary to osteoarthritis and rheumatoid arthritis. Surgical models of acute pain have demonstrated superior pain relief to placebo. The objective of this study was to test the safety and efficacy of celecoxib for pain relief after tonsillectomy compared to placebo., Methods: Adult subjects were randomized to 200 mg celecoxib versus placebo with a loading dose the night before surgery then twice daily for 10 days. Subjects were instructed to supplement the study drug with hydrocodone/acetaminophen liquid or acetaminophen for pain as needed. Subjects completed a daily diary regarding their pain, nausea, vomiting, diet, and activity., Results: Seventeen subjects enrolled. Intraoperative blood loss was similar between groups, and no subject had postoperative bleeding. Three patients returned to the emergency department for treatment, and 2 patients could not complete the diaries, all in the placebo group. Subjects in the placebo group required statistically significant (P < .05) higher doses of narcotic and acetaminophen to control pain. Pain and diet rating scores were slightly better in the celecoxib group compared to placebo., Conclusions: In this small cohort, celecoxib reduced postoperative narcotic and acetaminophen requirements compared to placebo without complications., (© The Author(s) 2016.)
- Published
- 2016
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7. Acute Rhinosinusitis: Prescription Patterns in a Real-World Setting.
- Author
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Benninger MS, Holy CE, and Trask DK
- Subjects
- Acute Disease, Female, Guideline Adherence, Humans, Male, Retrospective Studies, United States, Practice Patterns, Physicians' statistics & numerical data, Rhinitis drug therapy, Sinusitis drug therapy
- Abstract
Objective: Understand real-world prescription patterns for patients presenting with a first diagnosis of ARS and evaluate adherence to published medical guidelines., Study Design: Retrospective administrative database analysis., Setting: US-based outpatient settings., Methods: From a US claims database (MarketScan), 99,033 patients were identified with acute rhinosinusitis (ARS) in 2012 ("index"), with a complete medical and prescription history for 12 months preindex and 18 months postindex and no diagnoses of asthma or chronic rhinosinusitis. Of these, a random 10,000-patient sample was generated matched for age and sex to the initial cohort. Prescriptions and procedures at index, as well as complications up to 12 months postindex, were analyzed., Results: Nearly 90% of all patients received a prescription at index. Antibiotics were prescribed for 84.8% patients, followed by antitussives (16.2% for adults, 6.2% for pediatrics), nasal corticosteroids (15.5% adults, 7.5% for pediatrics), and systemic corticosteroids (10.3% for adults, 5.5% for pediatrics), with 49% adults and 29% children receiving >1 medication at first visit. Macrolides were the most frequently prescribed antibiotics (35.6% adults, 28.6% pediatrics), followed by amoxicillin/clavulanate and amoxicillin. Within 12 months of index, 3 patients presented with meningitis and 3 with orbital cellulitis., Conclusion: Significant variability in ARS treatment was observed, highlighting the need for heightened awareness of existing guidelines., (© American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.)
- Published
- 2016
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8. Detection of metastatic head and neck squamous cell carcinoma using the relative expression of tissue-specific mir-205.
- Author
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Fletcher AM, Heaford AC, and Trask DK
- Abstract
The presence of cervical lymph node metastases in head and neck squamous cell carcinoma (HNSCC) is the strongest determinant of patient prognosis. Owing to the impact of nodal metastases on patient survival, a system for sensitive and accurate detection is required. Clinical staging of lymph nodes is far less accurate than pathological staging. Pathological staging also suffers limitations because it fails to detect micrometastasis in a subset of nodal specimens. To improve the sensitivity of existing means of diagnosing metastatic disease, many advocate the use of molecular markers specific for HNSCC cells. MicroRNA (miRNA) are short noncoding segments of RNA that posttranscriptionally regulate gene expression. Approximately one third of all miRNA will exhibit substantial tissue specificity. Using a quantitative reverse transcription-polymerase chain reaction-based assay, we examined the expression of microRNA-205 (mir-205) across tissues and demonstrated that its expression is highly specific for squamous epithelium. We applied this assay to tissue samples, and we could detect metastatic HNSCC in each positive lymph node specimen, whereas benign specimens did not express this marker. When compared to metastases from other primary tumors, HNSCC-positive lymph nodes were distinguishable by the high expression of this marker. Using an in vitro lymphoid tissue model, we were able to detect as little as one squamous cell in a background of 1 million lymphocytes. By combining the sensitivity of quantitative reverse transcription-polymerase chain reaction with the specificity of mir-205 for squamous epithelium, we demonstrate a novel molecular marker for the detection of metastatic HNSCC.
- Published
- 2008
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9. Coblation-assisted lingual tonsillectomy for dysphagia secondary to tongue base hypertrophy.
- Author
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Bock JM and Trask DK
- Subjects
- Adult, Female, Humans, Hypertrophy, Palatine Tonsil pathology, Catheter Ablation, Deglutition Disorders etiology, Deglutition Disorders surgery, Tongue pathology, Tonsillectomy methods
- Abstract
Objectives: Lingual tonsillar hypertrophy is an underappreciated cause of dysphagia and is believed to impede swallowing function by inhibition of laryngeal elevation and epiglottic inversion due to mechanical interference by bulky tongue base tissue. We present a case of severe dysphagia secondary to idiopathic tongue base hypertrophy that was treated with coblation lingual tonsillectomy and tongue base reduction., Methods: We report a case and discuss the relevant literature regarding tongue base hypertrophy and surgical interventions to treat the enlarged base of the tongue., Results: Symptoms of dysphagia and globus sensation and signs of decreased epiglottic inversion and laryngeal penetration improved markedly after surgical reduction of hypertrophied lingual tonsillar tissue using coblation. Preoperative and postoperative clinical imaging and radiographs are presented to show the reduction of tongue base size, correlated with the patient's improved clinical function., Conclusions: Coblation-assisted lingual tonsillectomy and tongue base reduction can successfully treat dysphagia secondary to tongue base hypertrophy.
- Published
- 2008
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10. Modulation of cellular invasion by VEGF-C expression in squamous cell carcinoma of the head and neck.
- Author
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Bock JM, Sinclair LL, Bedford NS, Jackson RE, Lee JH, and Trask DK
- Subjects
- Cell Culture Techniques, Cell Line, Tumor, Cell Movement, Humans, Neoplasm Invasiveness, Transduction, Genetic, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell pathology, Head and Neck Neoplasms metabolism, Head and Neck Neoplasms pathology, RNA Interference, Vascular Endothelial Growth Factor C physiology
- Abstract
Objective: To determine how vascular endothelial growth factor C (VEGF-C) affects tumor cell invasion and motility in squamous cell carcinoma of the head and neck (SCCHN)., Design: A molecular biology study. The VEGF-C coding sequence was cloned into an expression vector and stably transfected into the SCCHN cell line SCC116 to create the SCC116-VEGFC line. RNA interference (RNAi) was used to block VEGF-C expression. An adenoviral system for expressing VEGF-C RNAi was developed and tested., Setting: An academic hospital laboratory., Main Outcome Measures: Relative VEGF-C RNA levels were determined by real-time quantitative reverse transcriptase-polymerase chain reaction, and protein expression was evaluated by Western blot. Cellular invasion was evaluated by 24-hour semipermeable membrane transit assay., Results: SCC116-VEGFC cells had markedly increased expression of VEGF-C protein and RNA compared with normal SCC116 controls. SCC116-VEGFC cells produced marked increases in cellular invasion and motility compared with SCC116 cells. Blockade of VEGF-C expression by transfection of a VEGF-C RNAi expression plasmid into both SCC116 and SCC116-VEGFC cells induced a 38% decrease in SCCHN invasion and motility as tested by a semipermeable membrane invasion assay. We developed an adenoviral expression system for VEGF-C RNAi, which also induced a dose-dependent decrease in cellular invasion in the highly invasive DM12 cell line., Conclusions: These studies demonstrate that intracellular VEGF-C levels modulate in vitro SCCHN motility and invasion. Further work is needed to clarify the specific receptors and signaling pathways that are involved in SCCHN motility. Molecular therapies that inhibit the VEGF-C pathway may have clinical potential in the treatment of lymphatic metastasis in SCCHN.
- Published
- 2008
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11. Relative non-steroidal anti-inflammatory drug (NSAID) antiproliferative activity is mediated through p21-induced G1 arrest and E2F inhibition.
- Author
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Bock JM, Menon SG, Goswami PC, Sinclair LL, Bedford NS, Domann FE, and Trask DK
- Subjects
- Apoptosis, Celecoxib, E2F Transcription Factors antagonists & inhibitors, Humans, Pyrazoles pharmacology, Sulfonamides pharmacology, Sulindac analogs & derivatives, Sulindac pharmacology, Tumor Cells, Cultured, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Cell Proliferation drug effects, Cyclin-Dependent Kinase Inhibitor p21 pharmacology, G1 Phase drug effects
- Abstract
This study was performed to compare the relative antineoplastic activity of 10 different non-steroidal anti-inflammatory drugs (NSAIDs) in clinical use, and to investigate the underlying mechanisms of this activity in a squamous cell carcinoma of the head and neck model (SCCHN). A standard 5-day MTT assay was used to calculate IC(50) values in UM-SCC-1 cells for 10 NSAIDs, including celecoxib, rofecoxib, sulindac sulfide, sulindac sulfone, indomethacin, ketoprofen, flurbiprofen, naproxen, piroxicam, and aspirin. Celecoxib, a COX-2 specific inhibitor, was by far the most potent NSAID, with an IC(50) of 39.9 +/- 1.1 microM, followed by sulindac sulfide (116.5 +/- 2.34 microM). Celecoxib and sulindac sulfide also induced more activation of caspase-3 than any other NSAID. Cell cycle analysis showed that celecoxib and sulindac sulfide both induced a 3-fold increase in G(1) phase distribution, and this correlated with strong induction of p21(waf1/cip1), inhibition of cyclin D1, and hypophosphorylation of Rb. Celecoxib and sulindac sulfide treatment induced strong downstream inhibition of E2F transactivating activity as determined by a luciferase reporter assay. These data demonstrate the wide range of activity of various NSAID agents, and reveal a mechanism of action through cell cycle inhibition and induction of apoptosis., (2007 Wiley-Liss, Inc)
- Published
- 2007
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12. Celecoxib toxicity is cell cycle phase specific.
- Author
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Bock JM, Menon SG, Sinclair LL, Bedford NS, Goswami PC, Domann FE, and Trask DK
- Subjects
- Animals, Apoptosis drug effects, Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell pathology, Celecoxib, Cell Growth Processes drug effects, Cyclin-Dependent Kinase Inhibitor p21 biosynthesis, Cyclin-Dependent Kinase Inhibitor p21 genetics, E2F Transcription Factors antagonists & inhibitors, E2F Transcription Factors metabolism, Female, Head and Neck Neoplasms genetics, Head and Neck Neoplasms metabolism, Head and Neck Neoplasms pathology, Humans, Mice, Mice, Nude, RNA, Messenger biosynthesis, RNA, Messenger genetics, Transcriptional Activation drug effects, Carcinoma, Squamous Cell drug therapy, G1 Phase drug effects, Head and Neck Neoplasms drug therapy, Pyrazoles pharmacology, S Phase drug effects, Sulfonamides pharmacology
- Abstract
Celecoxib inhibits proliferation and induces apoptosis in human tumors, but the molecular mechanisms for these processes are poorly understood. In this study, we evaluated the ability of celecoxib to induce toxicity in head and neck squamous cell carcinomas (HNSCC) and explored the relationships between celecoxib-induced cell cycle inhibition and toxicity in HNSCC. Celecoxib inhibited the proliferation of UM-SCC-1 and UM-SCC-17B cells both in vitro and in vivo, accompanied by G(1) phase cell cycle arrest and apoptosis. Celecoxib induced p21(waf1/cip1) at the transcriptional level independent of wild-type p53 function, leading to decreased expression of cyclin D1 and hypophosphorylation of Rb, with subsequent marked downstream decreases in nuclear E2F-1 protein expression and E2F transactivating activity by luciferase reporter assay. Cell cycle phase-specific cytometric sorting showed that celecoxib induced clonogenic toxicity preferentially to cells within the S phase greater than G(1) and G(2) phases. Levels of p21(waf1/cip1) and cyclin D1 protein were reduced in the S phase compared with the G(1) and G(2) phases, suggesting a possible protective role for p21(waf1/cip1) expression in celecoxib toxicity. In conclusion, we show that celecoxib has marked antiproliferative activity against head and neck cancer cells through transcriptional induction of p21(waf1/cip1) and G(1) phase accumulation leading to S phase-specific clonogenic toxicity. We additionally show that a profound inhibition of nuclear E2F function provides a possible mechanism for this S phase-specific toxicity.
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- 2007
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13. Skull base thrombotic mycosis.
- Author
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Wilkinson EP, Robinson RA, and Trask DK
- Subjects
- Aged, Coronary Artery Bypass, Diagnosis, Differential, Fatal Outcome, Humans, Male, Postoperative Complications, Candidiasis complications, Nasopharyngeal Diseases microbiology, Osteomyelitis microbiology, Skull Base microbiology, Venous Thrombosis etiology
- Published
- 2007
14. Differential activity of sulindac metabolites against squamous cell carcinoma of the head and neck is mediated by p21waf1/cip1 induction and cell cycle inhibition.
- Author
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Bock JM, Menon SG, Goswami PC, Sinclair LL, Bedford NS, Jackson RE, and Trask DK
- Subjects
- Apoptosis, Cell Cycle drug effects, Cell Cycle Proteins metabolism, Cell Proliferation drug effects, Humans, PPAR gamma antagonists & inhibitors, Sulindac metabolism, Sulindac pharmacology, Tumor Suppressor Protein p53 metabolism, Up-Regulation, Carcinoma, Squamous Cell metabolism, Cyclin-Dependent Kinase Inhibitor p21 metabolism, Head and Neck Neoplasms metabolism, Sulindac analogs & derivatives
- Abstract
Sulindac sulfide and sulindac sulfone have demonstrated anti-neoplastic and chemo-preventive activity against various human tumors, but few studies have examined the relative effectiveness of these drugs against squamous cell carcinoma of the head and neck (SCCHN). These compounds are metabolites of the nonsteroidal anti-inflammatory drug sulindac and differ in their ability to inhibit cyclooxygenase-2 (COX-2) enzyme function. Sulindac sulfide (the sulindac metabolite with COX-2 inhibitory function) demonstrated strong cell growth inhibition as measured by MTT and growth assays in UM-SCC-1 and SCC-25 cells, while sulindac sulfone had only moderate effect. Growth inhibition by sulindac sulfide was associated with a significant increase in percent G cells and activation of caspase-3. Sulindac sulfide induced expression of p21wafl/cipl in a dose-dependent fashion, decreased cyclin D1 protein levels, and increased Rb hypophosphorylation. p21waf1/cip1 protein levels increased without a significant increase in wild-type p53, suggesting that sulindac sulfide induces a p53-independent pathway regulating p2lwafl/ciP1 protein levels in SCCHN. Sulindac sulfide also induced dose-dependent expression of PPAR-gamma. In contrast, sulindac sulfone did not significantly alter apoptosis, cell cycle distribution or G1 checkpoint protein expression at doses below 200 microM. These results demonstrate the differential activity of sulindac metabolites and support the hypothesis that sulindac sulfide induced perturbations in SCCHN cellular proliferation could be regulated both by p21waf1/cip1-dependent cytostatic and caspase-dependent cytotoxic pathways.
- Published
- 2007
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15. Long-term quality of life for surgical and nonsurgical treatment of head and neck cancer.
- Author
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El-Deiry M, Funk GF, Nalwa S, Karnell LH, Smith RB, Buatti JM, Hoffman HT, Clamon GH, Graham SM, Trask DK, Dornfeld KJ, and Yao M
- Subjects
- Combined Modality Therapy, Female, Head and Neck Neoplasms drug therapy, Head and Neck Neoplasms radiotherapy, Health Status Indicators, Humans, Hypopharyngeal Neoplasms drug therapy, Hypopharyngeal Neoplasms radiotherapy, Hypopharyngeal Neoplasms surgery, Laryngeal Neoplasms drug therapy, Laryngeal Neoplasms radiotherapy, Laryngeal Neoplasms surgery, Male, Middle Aged, Oropharyngeal Neoplasms drug therapy, Oropharyngeal Neoplasms radiotherapy, Oropharyngeal Neoplasms surgery, Pharyngeal Neoplasms drug therapy, Pharyngeal Neoplasms radiotherapy, Speech, Alaryngeal, Head and Neck Neoplasms surgery, Pharyngeal Neoplasms surgery, Quality of Life
- Abstract
Objective: To compare the long-term, health-related quality-of-life outcomes in patients with advanced head and neck cancer (HNC) treated with surgery and postoperative radiation therapy (SRT) or concurrent chemotherapy and radiation therapy (CRT)., Design: Matched-pair study comparing patients with advanced HNC treated with SRT or CRT at least 12 months after treatment. Patients completed 2 validated surveys addressing HNC-specific outcomes and depressive symptoms and provided information on employment and tobacco and alcohol use. Results for the 2 groups were compared using paired-sample t test and chi2 analysis., Setting: University-based study., Patients: Patients with stage III or IV squamous cell carcinoma of the oropharynx, hypopharynx, and larynx who underwent SRT or received CRT., Main Outcome Measures: Head and neck cancer-specific health-related quality of life from the Head and Neck Cancer Inventory and level of depressive symptoms from the Beck Depression Inventory., Results: The matching process resulted in 27 patients in each treatment group. The HNC-specific domain scores (with higher scores representing better outcomes) for CRT vs SRT were eating, 37.8 vs 40.8 (P = .69); speech, 65.1 vs 56.0 (P = .23); aesthetics, 80.3 vs 69.2 (P = .14); and social disruption, 69.7 vs 70.6 (P = .90). Overall health-related quality of life was 64.0 with SRT and 55.0 with CRT (P = .142). For the Beck Depression Inventory (with higher scores representing worse outcomes), patients who underwent SRT had a mean score of 9.6 compared with 11.6 for patients who received CRT (P = .42)., Conclusion: As nonsurgical means of treating HNC have become more aggressive and surgical techniques have become more focused on function preservation and rehabilitation, the overall health-related quality of life resulting from these different approaches is similar.
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- 2005
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16. Oral melanoacanthoma: a case report, a review of the literature, and a new treatment option.
- Author
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Andrews BT and Trask DK
- Subjects
- Acanthoma ethnology, Black or African American, Biopsy, Fine-Needle, Dendritic Cells pathology, Follow-Up Studies, Humans, Male, Melanocytes pathology, Melanoma ethnology, Middle Aged, Mouth Neoplasms ethnology, Treatment Outcome, Acanthoma surgery, Electrocoagulation methods, Melanoma surgery, Mouth Neoplasms surgery
- Abstract
Objectives: Oral melanoacanthoma is a rare condition that presents as a pigmented, painful lesion, most commonly on the buccal mucosa. Argon plasma coagulation is a new treatment option for benign oral lesions and is hypothesized to be efficacious for this rare mucosal disorder., Methods: Treatment of a case and a review of the English-language literature were performed., Results: One patient received a diagnosis of oral melanoacanthoma, and argon plasma coagulation treatment resulted in ablation of the lesion with excellent mucosal healing. A review of the literature demonstrated that this lesion is most commonly associated with black (90.9%), adult female (69.7%) patients and is most commonly located on the buccal mucosa (64.7%)., Conclusions: Oral melanoacanthoma is a rare, benign mucosal lesion that may require surgical intervention for symptomatic relief. Argon plasma coagulation is a relatively safe and effective means of treating this lesion. Argon plasma coagulation treatment may be expanded to include other benign, superficial lesions of the oral mucosa.
- Published
- 2005
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17. Reversal of cisplatin resistance with a BH3 mimetic, (-)-gossypol, in head and neck cancer cells: role of wild-type p53 and Bcl-xL.
- Author
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Bauer JA, Trask DK, Kumar B, Los G, Castro J, Lee JS, Chen J, Wang S, Bradford CR, and Carey TE
- Subjects
- Antineoplastic Agents pharmacology, Apoptosis drug effects, Carcinoma, Squamous Cell metabolism, Drug Resistance, Neoplasm, Gossypol chemistry, Head and Neck Neoplasms metabolism, Humans, Molecular Mimicry, Mutation, Peptide Fragments chemistry, Proto-Oncogene Proteins chemistry, Tumor Cells, Cultured, Tumor Suppressor Protein p53 drug effects, Tumor Suppressor Protein p53 genetics, Carcinoma, Squamous Cell drug therapy, Cisplatin pharmacology, Gossypol pharmacology, Head and Neck Neoplasms drug therapy, Tumor Suppressor Protein p53 metabolism
- Abstract
Organ preservation protocols in head and neck squamous cell carcinoma (HNSCC) are limited by tumors that fail to respond. We observed that larynx preservation and response to chemotherapy is significantly associated with p53 overexpression, and that most HNSCC cell lines with mutant p53 are more sensitive to cisplatin than those with wild-type p53. To investigate cisplatin resistance, we studied two HNSCC cell lines, UM-SCC-5 and UM-SCC-10B, and two resistant sublines developed by cultivation in gradually increasing concentrations of cisplatin. The cisplatin-selected cell lines, UM-SCC-5PT and UM-SCC-10BPT, are 8 and 1.5 times more resistant to cisplatin than the respective parental cell lines, respectively. The parental lines overexpress p53 and contain p53 mutations but the cisplatin-resistant cell lines do not, indicating that cells containing mutant p53 were eliminated during selection. Bcl-x(L) expression increased in the cisplatin-resistant lines relative to the parental lines, whereas Bcl-2 expression was high in the parental lines and decreased in the cisplatin-resistant lines. Thus, cisplatin selected for wild-type p53 and high Bcl-x(L) expression in these cells. We tested a small-molecule BH3 mimetic, (-)-gossypol, which binds to the BH3 domain of Bcl-2 and Bcl-x(L), for activity against the parental and cisplatin-resistant cell lines. At physiologically attainable levels, (-)-gossypol induces apoptosis in 70% to 80% of the cisplatin-resistant cells but only in 25% to 40% of the parental cells. Thus, cisplatin-resistant cells seem to depend on wild-type p53 and Bcl-x(L) for survival and BH3 mimetic agents, such as (-)-gossypol, may be useful adjuncts to overcome cisplatin resistance in HNSCC.
- Published
- 2005
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18. Molecular profiling and the identification of genes associated with metastatic oral cavity/pharynx squamous cell carcinoma.
- Author
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Schmalbach CE, Chepeha DB, Giordano TJ, Rubin MA, Teknos TN, Bradford CR, Wolf GT, Kuick R, Misek DE, Trask DK, and Hanash S
- Subjects
- Carcinoma, Squamous Cell secondary, Cohort Studies, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Humans, Lymphatic Metastasis, Mouth Neoplasms pathology, Neoplasm Staging, Oligonucleotide Array Sequence Analysis, Oropharyngeal Neoplasms pathology, Prospective Studies, RNA, Neoplasm genetics, Tissue Inhibitor of Metalloproteinase-1 metabolism, Carcinoma, Squamous Cell genetics, Mouth Neoplasms genetics, Oropharyngeal Neoplasms genetics
- Abstract
Objective: To investigate differences in gene expression profiles between oral cavity/oropharynx squamous cell carcinoma (OC/OP SCC) primary tumors that have metastasized to cervical lymph nodes and nonmetastatic OC/OP SCC tumors., Design: Oligonucleotide microarray analysis of primary tumors was used to produce gene expression profiles. Profile comparisons between metastatic and nonmetastatic tumors were performed using principal component analysis, t test, and fold change differences. A similar comparison between metastatic tumors and noncancer oral mucosa samples was performed to ensure tumor origin., Subjects: A prospective cohort of 20 patients with previously untreated OC/OP SCC who underwent pathologic staging following surgical resection and lymphadenectomy., Results: Of the approximately 9600 genes profiled, 101 demonstrated significant expression differences between the metastatic and nonmetastatic tumors (fold change > or =1.5; P<.01). Among this subset, 57 genes also exhibited significant differences between metastatic tumors and normal mucosa samples (fold change > or =1.5; P<.05). This profile included genes related to the extracellular matrix, adhesion, motility, inflammation, and protease inhibition. Collagen type 11 alpha-1 (COL11A1) demonstrated the greatest differential expression between metastatic and nonmetastatic OC/OP SCC tumors (fold change=7.61; P=.002). Tissue inhibitor of metalloproteinase 1 (TIMP-1) also demonstrated increased expression in metastatic tumors (fold change=3.3; P=.003)., Conclusions: Metastatic OC/OP SCC has a distinct gene expression profile compared with nonmetastatic OC/OP SCC and normal oral mucosa. This metastatic profile includes genes related to the extracellular matrix, adhesion, motility, and protease inhibition. Knowledge gained through tumor gene expression profiling may facilitate early detection of aggressive tumors and targeted therapeutic interventions.
- Published
- 2004
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19. Genetically targeted radiotherapy of head and neck squamous cell carcinoma using the sodium-iodide symporter (NIS).
- Author
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Gaut AW, Niu G, Krager KJ, Graham MM, Trask DK, and Domann FE
- Subjects
- Adenoviridae genetics, Animals, Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell metabolism, Cell Line, Tumor, Feasibility Studies, Female, Head and Neck Neoplasms genetics, Head and Neck Neoplasms metabolism, Iodine Radioisotopes administration & dosage, Mice, Mice, Nude, Symporters metabolism, Carcinoma, Squamous Cell radiotherapy, Genetic Therapy methods, Head and Neck Neoplasms radiotherapy, Symporters genetics
- Abstract
Background: Gene therapy that uses delivery of the sodium-iodide symporter (NIS) gene followed by radioiodide administration has been proposed as a novel form of radiotherapy for nonthyroidal cancers., Methods: In vitro [(125)I] iodide accumulation and efflux from cells was determined after treatment with an NIS-expressing adenovirus (Ad-NIS). A clonogenic survival assay and tumor growth experiment that used athymic mice were used to demonstrate the in vitro and in vivo cytotoxicity of Ad-NIS treatment and [(131)I] iodide delivery., Results: Head and neck squamous cell carcinoma (HNSCC) cell lines treated with Ad-NIS exhibit significant amounts of radioiodide accumulation and retention. In vitro HNSCC cell survival was significantly diminished after NIS gene delivery followed by administration of [(131)I] iodide. Moreover, NIS gene transfer/[(131)I] iodide administration dramatically attenuated HNSCC tumor formation in athymic mice., Conclusions: Our data demonstrate the feasibility of genetically targeted radiotherapy by use of the NIS gene as a possible therapeutic intervention in head and neck cancer., (Copyright 2004 Wiley Periodicals, Inc. Head Neck 26: 265-271, 2004)
- Published
- 2004
- Full Text
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20. Validation of tissue microarrays using p53 immunohistochemical studies of squamous cell carcinoma of the larynx.
- Author
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Griffin MC, Robinson RA, and Trask DK
- Subjects
- Aged, Biopsy methods, Carcinoma, Squamous Cell metabolism, Female, Humans, Immunohistochemistry methods, Laryngeal Neoplasms metabolism, Larynx chemistry, Larynx pathology, Male, Middle Aged, Neoplasm Staging, Reproducibility of Results, Carcinoma, Squamous Cell pathology, Laryngeal Neoplasms pathology, Tumor Suppressor Protein p53 analysis
- Abstract
Tissue microarrays are a powerful new tissue-conserving technology in the study of cancer, allowing simultaneous study of a large number of tumor specimens. We sought to ascertain the utility of tissue microarrays in head and neck cancer pathology using squamous cell carcinoma of the larynx as a model system. Whole-specimen slides from 44 different laryngeal squamous cell carcinomas were stained for p53 expression. Microarrays were then generated by taking six 0.6-mm core biopsies from each of the 44 specimens. The whole sections and the microarrays were independently scored for p53 expression. Twenty-three (53%) of the 44 tumor specimens were positive for p53. Forty-four of the 264 core biopsies (17%) were not given a score because of the lack of tumor cells. Seventy-eight percent of the individual discs on the microarray had scores in agreement with those of the whole-section slides. Among biopsy discs with tumor cells present, 94.5% were in agreement with the whole-section slide. The average probability that four randomly chosen biopsy discs, considered together, would accurately identify the presence of p53 staining in a whole section was 0.97 (95% CI.93-1.0). We conclude that tissue microarrays for squamous cell carcinomas can accurately represent immunohistochemical results of whole-slide specimens when four or more samples are used. Tissue microarrays are an important technique that may be applied to immunohistochemical studies of head and neck cancer.
- Published
- 2003
- Full Text
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21. Presentation, treatment, and outcome of oral cavity cancer: a National Cancer Data Base report.
- Author
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Funk GF, Karnell LH, Robinson RA, Zhen WK, Trask DK, and Hoffman HT
- Subjects
- Adult, Age Distribution, Aged, Aged, 80 and over, Analysis of Variance, Carcinoma, Squamous Cell mortality, Female, Humans, Male, Middle Aged, Mouth Neoplasms mortality, Sex Distribution, Survival Rate, Treatment Outcome, United States, Carcinoma, Squamous Cell pathology, Carcinoma, Squamous Cell therapy, Databases as Topic statistics & numerical data, Mouth Neoplasms pathology, Mouth Neoplasms therapy
- Abstract
Background: Oral cancer has been identified as a significant public health threat. Systematic evaluation of the impact of this disease on the US population is of great importance to health care providers and policy makers., Methods: This study used the National Cancer Data Base (NCDB) to evaluate associations between demographic and disease characteristics, treatment, and survival for patients with oral cavity cancer in the United States. Of patients diagnosed between 1985 and 1996, 58,976 were extracted from the NCDB. ANOVAs were performed on selected cross-tabulations, and relative survival was used to calculate outcome., Results: Median age of patients was 64.0 years. Men made up 60.2% of patients. Pathologic diagnosis was squamous cell carcinoma (SCC) in 86.3% of cases. Younger patients had a much higher frequency of non-SCC, and this was related to survival in these patients. African-Americans (independent of income), lower income patients, and patients with higher grade disease were seen more frequently with advanced-stage SCC. Five-year relative survival for SCC cases was lower for older patients, men, and African-Americans., Conclusions: This study addressed many issues related to oral cancer that have been previously discussed in the literature. The demographic, site, stage, histologic, and survival data available for this large number of cases in the NCDB allowed an accurate characterization of the contemporary status of oral cancer in the United States., (Copyright 2002 John Wiley & Sons, Inc.)
- Published
- 2002
- Full Text
- View/download PDF
22. National survey of head and neck verrucous carcinoma: patterns of presentation, care, and outcome.
- Author
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Koch BB, Trask DK, Hoffman HT, Karnell LH, Robinson RA, Zhen W, and Menck HR
- Subjects
- Adult, Aged, Aged, 80 and over, Carcinoma, Verrucous diagnosis, Carcinoma, Verrucous mortality, Databases, Factual, Female, Head and Neck Neoplasms diagnosis, Head and Neck Neoplasms mortality, Humans, Male, Middle Aged, Neoplasm Staging, Treatment Outcome, Carcinoma, Verrucous therapy, Head and Neck Neoplasms therapy, Health Care Surveys
- Abstract
Background: Verrucous carcinoma is distinguished by controversy regarding appropriate diagnosis and treatment. This study provides a contemporary survey of demographics, patterns of care, and outcome for this disease in the United States., Methods: The National Cancer Data Base had 2350 cases of verrucous carcinoma of the head and neck diagnosed between 1985 and 1996. Statistical procedures included chi-square analyses, Student t tests, and relative survival., Results: Tumors originated most frequently in the oral cavity (55.9%) and larynx (35.2%). Although most patients were male (60.0%), oral cavity tumors were more common among older females. The most prevalent treatment was surgery alone (69.7%), followed by surgery combined with irradiation (11.0%) and irradiation alone (10.3%). For oral cavity tumors, surgery alone was more common among early (85.8%) than advanced cases (56.9%); a larger proportion of advanced disease received radiation alone or surgery and irradiation combined. Most laryngeal tumors were treated with surgery (60.3% for early and 55.6% for advanced disease), but a higher proportion received radiation alone or surgery combined with radiation compared with oral cavity cases. Five-year relative survival was 77.9%. For localized disease, survival after surgery was 88.9% compared with 57.6% after irradiation., Conclusions: Demographic differences implicate different mechanisms of carcinogenesis for verrucous carcinoma arising in the oral cavity and the larynx. Although selection bias may account for the differences observed, patients receiving initial treatment with surgery had better survival than those treated with irradiation, especially for cases originating in the oral cavity., (Copyright 2001 American Cancer Society.)
- Published
- 2001
- Full Text
- View/download PDF
23. Silicone oil in the repair of complex retinal detachments. A prospective observational multicenter study.
- Author
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Azen SP, Scott IU, Flynn HW Jr, Lai MY, Topping TM, Benati L, Trask DK, and Rogus LA
- Subjects
- Adult, Cohort Studies, Cytomegalovirus Retinitis complications, Eye Injuries complications, Female, Humans, Intraocular Pressure, Male, Middle Aged, Prospective Studies, Retinal Detachment etiology, Retinal Detachment physiopathology, Retinal Diseases complications, Silicone Oils adverse effects, Treatment Outcome, Visual Acuity, Retinal Detachment surgery, Silicone Oils administration & dosage, Vitrectomy
- Abstract
Objective: This study aimed to report anatomic and visual acuity outcomes and complications after 1000-centistoke silicone oil was used as a retinal tamponade for the treatment of complex retinal detachments., Design: Prospective observational multicenter study conducted at community and university-based ophthalmology clinics., Participants: The study cohort consisted of 2439 patients (2573 eyes) treated for complex retinal detachments associated with cytomegalovirus (CMV) necrotizing retinitis or a non-CMV etiology, including proliferative diabetic retinopathy, giant retinal tears, proliferative vitreoretinopathy, or ocular trauma., Intervention: Vitrectomy surgery was performed for complex retinal detachment with 1000-centistoke silicone oil as the retinal tamponade., Main Outcome Measures: Anatomic outcomes were complete retinal attachment and macular attachment. Visual acuity outcomes were ambulatory vision (> or = 4/200) and preservation of preoperative visual acuity. Complications were rates of secondary intraocular pressure elevation (> or = 30 mmHg), hypotony (< or = 5 mmHg), corneal opacification (including band keratopathy, corneal edema, and corneal abrasions), oil emulsification, and cataract. Outcomes were assessed 6, 12, and 24 months after surgery., Results: At the 6-month examination, the retina was completely attached in 178 (78%) of 228 CMV eyes and in 855 (70%) of 1219 non-CMV eyes. The macula was attached in 216 (95%) of 228 and 1062 (89%) of 1189 CMV and non-CMV eyes, respectively. Ambulatory vision was noted in 151 (65%) of 234 CMV eyes and in 480 (38%) of 1251 non-CMV eyes. Visual acuity was preserved in 106 (46%) of 230 and 1035 (84%) of 1229 CMV and non-CMV eyes, respectively. The corresponding rates of complications for CMV and non-CMV eyes were: elevated intraocular pressure, 0 (0%) of 196 and 35 (3%) of 1196; hypotony, 11 (6%) of 196 and 228 (19%) of 1196; corneal opacity, 13 (6%) of 229 and 326 (26%) of 1248; emulsification, 3 (1%) of 211 and 29 (3%) of 959; and cataract in phakic eyes, 118 (64%) of 185 and 50 (63%) of 80., Conclusions: Retinal reattachment was achieved in the majority of eyes using vitrectomy and silicone oil retinal tamponade. Complication rates generally were less frequent in CMV eyes, but follow-up was shorter in this group of patients, largely because of reduced life expectancy. Cataract frequently developed in phakic eyes of study patients. Use of 1000-centistoke silicone oil can be considered in the management of complex retinal detachments associated with multiple etiologies.
- Published
- 1998
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24. Silicone oil in repair of retinal detachments caused by necrotizing retinitis in HIV infection.
- Author
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Davis JL, Serfass MS, Lai MY, Trask DK, and Azen SP
- Subjects
- Adult, Cohort Studies, Female, Follow-Up Studies, Humans, Male, Prospective Studies, Retinal Detachment etiology, Treatment Outcome, Viscosity, Visual Acuity, Vitrectomy, HIV Infections complications, Retinal Detachment surgery, Retinal Necrosis Syndrome, Acute complications, Silicone Oils
- Abstract
Objective: To evaluate the safety and efficacy of 1000- and 5000-centistoke silicone oil as retinal tamponades for the treatment of retinal detachments secondary to necrotizing retinitis in patients with human immunodeficiency virus (HIV) infection., Design: A prospective observational study., Setting: Community and university-based ophthalmology clinics., Patients: Three hundred fifty patients with HIV infection, who had 407 eyes with retinal detachments secondary to necrotizing retinitis., Intervention: Vitrectomy surgery for retinal detachment with 1000- or 5000-centistoke silicone oil as the retinal tamponade., Outcome Measures: Efficacy was measured both by anatomic success (defined as complete retinal attachment or macular attachment) and by visual acuity success (defined as preservation of visual acuity or ambulatory vision). Safety was determined by the rate of complications, including abnormal intraocular pressure and corneal and lens opacification., Results: At the last follow-up examination, the retina was completely attached in 287 (73%) of 393 eyes, the macula was attached in 370 eyes (94%), 268 eyes (68%) had ambulatory vision, and visual acuity was preserved in 219 (56%) of 388 eyes. Corneal opacification, hypotony, and silicone oil emulsification were present in 4%, 2%, and 1% of eyes, respectively. One eye had elevated intraocular pressure. Of the 57 patients who had both eyes treated, 35 died, of whom four (11%) had nonambulatory vision in both eyes. Of the 293 patients who had one eye treated, 122 died, of whom 44 (36%) died with nonambulatory vision in the treated eye. The median time to cataract was 192 days; to nonambulatory vision, 474 days; and to death, 204 days., Conclusions: Silicone oil repair of retinal detachments in necrotizing retinitis is an efficacious and safe procedure that delays or prevents loss of vision in advanced HIV disease.
- Published
- 1995
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25. Blood-ocular barrier permeability and electroretinogram after intravitreal silicone oils of varying composition.
- Author
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Green K, Cheeks L, Slagle T, Paul H, and Trask DK
- Subjects
- Animals, Aqueous Humor metabolism, Biological Transport, Active drug effects, Blood metabolism, Cell Membrane Permeability drug effects, Dark Adaptation, Fluorescein, Fluoresceins metabolism, Fluorophotometry, Rabbits, Retina physiology, Siloxanes toxicity, Vitreous Body, Blood-Retinal Barrier drug effects, Electroretinography drug effects, Silicone Oils toxicity
- Abstract
Silicone oils, used as long-term retinal tamponades, cause retinal toxicity that may be related to certain ingredients. Specific additives, proven to increase corneal endothelial permeability, were added to a purified oil, and placed into the vitreous of rabbits to assess their effects on the retina. Oils were exchanged for vitreous at constant intraocular pressure to 1 ml oil volume. Blood-ocular barrier permeability was measured with fluorophotometry after intravenous dye, and retinal function was measured using dark-adapted electroretinography (ERG). Each parameter was determined at eight week intervals: this periodicity was chosen to allow any toxicity to develop based upon prior data in the literature. The fluorescein concentration in different ocular compartments indicated an increased aqueous humor fluorescein concentration after pure oil (a non-statistically significant 50% increase) or oil plus long chain additive (a significant 240% increase). After oil plus a linear series of compounds both aqueous humor (2000%) and anterior vitreous fluorescence (8000%) was statistically significantly increased, indicating a breakdown of the blood-aqueous barrier. The height of the b-wave of the ERG was unaffected by any oil in the presence or absence of additive. Overt changes were minimal with oil alone, increased with oil containing linear chain additive, and were extensive with oil with long chain additive.
- Published
- 1993
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26. Down-regulation of a calmodulin-related gene during transformation of human mammary epithelial cells.
- Author
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Yaswen P, Smoll A, Peehl DM, Trask DK, Sager R, and Stampfer MR
- Subjects
- Base Sequence, Cells, Cultured, Epithelial Cells, Female, Humans, Molecular Sequence Data, Nucleic Acid Hybridization, Oligonucleotide Probes, Polymerase Chain Reaction, RNA, Messenger genetics, RNA, Messenger isolation & purification, Sequence Homology, Nucleic Acid, Breast cytology, Calmodulin genetics, Cell Transformation, Neoplastic, Gene Expression Regulation, Genes
- Abstract
A human cDNA library obtained from cultured normal mammary epithelial cells (HMECs) was searched by subtractive hybridization for genes whose decrease in expression might be relevant to epithelial transformation. One clone identified by this procedure corresponded to a 1.4-kilobase mRNA, designated NB-1, whose expression was decreased greater than 50-fold in HMECs tumorigenically transformed in vitro after exposure to benzo[a]pyrene and Kirsten sarcoma virus. Sequence analysis of NB-1 cDNA revealed an open reading frame with a high degree of homology to calmodulin. NB-1 expression could be demonstrated by polymerase chain reaction amplification in normal breast, prostate, cervix, and epidermal tissues. The presence of NB-1 transcripts was variable in primary breast carcinoma tissues and undetectable in tumor-derived cell lines of breast, prostate, or other origins. NB-1 mRNA expression could be down-regulated in cultured HMECs by exposure to reconstituted extracellular matrix material, while exposure to transforming growth factor type beta increased its relative abundance. The protein encoded by NB-1 may have Ca2+ binding properties and perform functions similar to those of authentic calmodulin. Its possible roles in differentiation and/or suppression of tumorigenicity in epithelial tissues remain to be examined.
- Published
- 1990
- Full Text
- View/download PDF
27. Keratins as markers that distinguish normal and tumor-derived mammary epithelial cells.
- Author
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Trask DK, Band V, Zajchowski DA, Yaswen P, Suh T, and Sager R
- Subjects
- Blotting, Northern, Breast, Breast Neoplasms, Cell Line, DNA genetics, DNA, Neoplasm genetics, Electrophoresis, Gel, Two-Dimensional, Electrophoresis, Polyacrylamide Gel, Female, Gene Library, Humans, Keratins biosynthesis, Keratins genetics, Biomarkers, Tumor analysis, Epithelium metabolism, Keratins analysis, RNA, Messenger analysis, Tumor Cells, Cultured metabolism
- Abstract
Keratin 5 (K5) mRNA and protein are shown to be expressed in normal mammary epithelial cells in culture and are absent from tumor-derived cell lines. To extend these findings, the full complements of keratins in normal, immortalized, and tumor cells were compared. It is shown here that normal cells produce keratins K5, K6, K7, K14, and K17, whereas tumor cells produce mainly keratins K8, K18, and K19. In immortalized cells, which are preneoplastic or partially transformed, the levels of K5 mRNA and protein are lower than in normal cells, whereas the amount of K18 is increased. Thus, K5 is an important marker in the tumorigenic process, distinguishing normal from tumor cells, and decreased K5 expression correlates with tumorigenic progression.
- Published
- 1990
- Full Text
- View/download PDF
28. Suppression of tumor-forming ability and related traits in MCF-7 human breast cancer cells by fusion with immortal mammary epithelial cells.
- Author
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Zajchowski DA, Band V, Trask DK, Kling D, Connolly JL, and Sager R
- Subjects
- Animals, Cell Division, Cell Transformation, Neoplastic, Epithelial Cells, Female, Humans, Keratins analysis, Mice, Mice, Nude, Tumor Cells, Cultured cytology, Breast cytology, Breast Neoplasms pathology, Cell Fusion, Hybrid Cells cytology, Subrenal Capsule Assay, Transfection
- Abstract
Somatic cell hybrids between MCF-7 human breast cancer cells and normal immortalized human mammary epithelial cells have been obtained by polyethylene glycol-mediated cell fusion. The hybrid cells are suppressed in their ability to form tumors in nude mice, as well as in traits specific to the tumorigenic MCF-7 parent: growth factor independence, tumor necrosis factor sensitivity, and pS2 gene expression. In addition, they display other characteristics of the "normal" parent, including increased expression relative to the MCF-7 cells of the genes for the extracellular matrix component fibronectin, the intermediate filament keratin 5, and the angiogenesis inhibitor thrombospondin. The levels of keratins 8 and 18 also resemble those of the nontumorigenic parent. These results provide evidence for the existence of tumor suppressor gene products in immortal mammary epithelial cells. We propose a characteristic "suppressed" tumor cell phenotype, which encompasses altered cytoarchitecture, angiogenesis capabilities, and growth factor requirements.
- Published
- 1990
- Full Text
- View/download PDF
29. Biochemical characterization of topoisomerase I purified from avian erythrocytes.
- Author
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Trask DK and Muller MT
- Subjects
- Animals, Cell Nucleus enzymology, Chickens, DNA metabolism, DNA Topoisomerases, Type I blood, DNA Topoisomerases, Type I metabolism, Molecular Weight, Protein Binding, DNA Topoisomerases, Type I analysis, Erythrocytes enzymology
- Abstract
A type I topoisomerase has been purified from avian erythrocyte nuclei. The most pure fraction contains one major polypeptide of Mr = 105,000 (80% of total) and several minor ones of lower molecular weight. Active forms of the topoisomerase were identified by covalently binding the enzyme to 32P-DNA, digesting with nuclease and detecting 32P labeled peptides by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Topoisomerase activity, as measured by the ability to covalently bind DNA, is associated with the following peptides: Mr = 105, 83, 54 and 30,000. The similar chromatographic properties of the various forms of topoisomerase suggests a common structural identity as previously proposed for the HeLa topoisomerase I (Liu, L.F. and Miller, K.G. (1981) Proc. Natl. Acad. Sci. USA 78, 3487-3491). The avian enzyme is similar to other eucaryotic type I DNA topoisomerases in that it covalently binds double and single stranded DNA forming an enzyme linked to the 3'-phosphoryl end and after binding to single stranded DNA it can transfer the single stranded donor DNA to an acceptor DNA possessing 5'-OH end groups. The binding site size of topoisomerase on DNA has also been determined using micrococcal nuclease to digest unprotected DNA in the native enzyme/DNA complex. The enzyme blocks access to the helix over a span of 25 bp. These findings are discussed in light of the distribution and function of topoisomerase I in chromatin.
- Published
- 1983
- Full Text
- View/download PDF
30. Rapid detection and isolation of covalent DNA/protein complexes: application to topoisomerase I and II.
- Author
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Trask DK, DiDonato JA, and Muller MT
- Subjects
- DNA-Binding Proteins analysis, Potassium, Sodium Dodecyl Sulfate, DNA analysis, DNA Topoisomerases, Type I isolation & purification, Deoxyribonucleoproteins isolation & purification
- Abstract
A rapid and simple method has been developed which allows detection and isolation of covalent DNA/protein adducts. The method is based upon the use of an ionic detergent, SDS, to neutralize cationic sites of weakly bound proteins thereby resulting in their dissociation off the helix. Proteins tightly or covalently bound to DNA that are not dissociable by SDS, result in the precipitation of the DNA fragment by the addition of KCl; however, free nucleic acid does not precipitate. The method is particularly useful as an analytical tool to titrate the binding of prototypic covalent binding proteins, topoisomerase I and II; thus, quantitation of topoisomerase activity is possible under defined conditions. As an analytical tool the method can be used as a general assay in the purification of as yet unidentified topoisomerases or other activities that bind DNA covalently. Moreover, the technology can be adapted for use in a preparative mode to separate covalent complexes from free DNA in a single step.
- Published
- 1984
- Full Text
- View/download PDF
31. Inhibition of potentially lethal DNA damage repair in human tumor cells by beta-lapachone, an activator of topoisomerase I.
- Author
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Boothman DA, Trask DK, and Pardee AB
- Subjects
- Animals, Chickens, DNA Topoisomerases, Type II metabolism, Enzyme Activation, Humans, Kinetics, Time Factors, DNA Damage, DNA Repair drug effects, DNA Topoisomerases, Type I metabolism, Naphthoquinones pharmacology
- Abstract
A 4-h posttreatment with 4 microM beta-lapachone was previously shown to enhance the lethality of X-rays against human laryngeal epidermoid carcinoma (HEp-2) cells (D. A. Boothman et al., Cancer Res., 47:5361-5366, 1988). We now show that beta-lapachone (a) activates the DNA-unwinding activity of topoisomerase I, (b) inhibits the fast component of potentially lethal damage repair (PLDR) carried out by HEp-2 cells when present during or immediately following X-irradiation, (c) specifically and synergistically enhances the cytotoxic effects of DNA-damaging agents which induce DNA strand incisions, such as neocarzinostatin or X-rays, against a radioresistant human malignant melanoma (U1-Mel) cell line, (d) does not synergistically potentiate melphalan-induced lethality against U1-Mel cells but inhibits survival recovery and increases sister chromatid exchanges, and (e) does not further enhance the lethal effects of X-rays following prolonged drug exposures, indicating that beta-lapachone modifies initially created DNA lesions or inhibits lesion repair but does not create lethal lesions by itself. beta-Lapachone accelerated the DNA-unwinding activity of topoisomerase I derived from avian erythrocytes, calf thymus, or HEp-2 cells. beta-Lapachone did not intercalate into DNA, nor did it inhibit topoisomerase II or ligation carried out by mammalian or T4 DNA ligases. Structurally similar analogues, alpha-lapachone, lapachol, and dichloroallyl lawsone, did not enhance X-ray-induced cytotoxicity nor did they activate topoisomerase I. Camptothecin, a specific inhibitor of topoisomerase I, significantly radiosensitized HEp-2 cells, in a manner similar to beta-lapachone. These results suggest a role of topoisomerase I in DNA repair. The PLDR capacity of confluent-arrested HEp-2 cells was inhibited when beta-lapachone was given immediately following or during X-irradiation. The effect decreased when the drug was added at later times. beta-Lapachone may enhance lethality by converting single- into double-stranded DNA breaks during PLDR or through DNA conformational changes which inhibit PLDR. We propose that either mechanism of enhanced lethality may result from the ability of beta-lapachone to activate topoisomerase I.
- Published
- 1989
32. Stabilization of type I topoisomerase-DNA covalent complexes by actinomycin D.
- Author
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Trask DK and Muller MT
- Subjects
- Cell Line, Cell Nucleolus metabolism, Chemical Phenomena, Chemistry, DNA-Binding Proteins metabolism, Temperature, DNA Topoisomerases, Type I metabolism, DNA, Ribosomal metabolism, Dactinomycin pharmacology, Transcription, Genetic drug effects
- Abstract
The activity of the endogenous DNA topoisomerase type I (EC 5.99.1.2) can be quantified in situ by determining how efficiently the enzyme is trapped in a covalent complex with DNA upon lysis of nuclei with detergents. In this way, we can measure relative levels of topoisomerase binding to DNA at native sites in chromatin. Since the majority of topoisomerase I is localized in the nucleolus at rRNA genes, we have evaluated how low levels of actinomycin D, which terminate transcription of rRNA genes, affect the activity of topoisomerase I. In vivo, as well as in vitro with purified topoisomerase I, we have found that drug treatment extends the half-life of the covalent topoisomerase-DNA complex. Actinomycin D stabilizes the nicked intermediate in the cleavage and resealing reaction but otherwise does not significantly alter the strand-passing ability of topoisomerase I. Sequence-specific cleavages by topoisomerase I were stimulated by actinomycin D at identical sequences recognized by the enzyme in the absence of drug. The localization of topoisomerase I in the nucleolus, coupled with the observation that transcription in this organelle is highly sensitive to actinomycin D and camptothecin treatment, leads us to propose that topoisomerase I contributes to actinomycin D inhibition of transcription.
- Published
- 1988
- Full Text
- View/download PDF
33. Eukaryotic type I topoisomerase is enriched in the nucleolus and catalytically active on ribosomal DNA.
- Author
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Muller MT, Pfund WP, Mehta VB, and Trask DK
- Subjects
- Animals, Antibodies immunology, Base Sequence, DNA Topoisomerases, Type I immunology, Microscopy, Electron, Rabbits, Transcription, Genetic, Cell Nucleolus enzymology, DNA Topoisomerases, Type I analysis, DNA, Ribosomal metabolism
- Abstract
The distribution of eukaryotic DNA topoisomerase I in the cell has been analyzed at four levels: (i) at the level of the nuclear matrix; (ii) at the cytological level by immunofluorescence of whole cells; (iii) at the electron microscopic level using the protein A/colloidal gold technique; and (iv) at the level of DNA to identify in situ the sequence upon which topoisomerase I is catalytically active. Although topoisomerase I is clearly distributed non-randomly in the nucleus, the unique distribution of the enzyme is not related to the nuclear matrix. The data support the conclusion that topoisomerase I is heavily concentrated in the nucleolus of the cell; furthermore, particular regions within the nucleolus are depleted of topoisomerase. A technique has been developed which allows isolation and analysis of the cellular DNA sequences covalently attached to topoisomerase. Ribosomal DNA sequences are at least 20-fold enriched in topoisomerase/DNA complexes isolated directly from a chromosomal setting, relative to total DNA. This is the first direct evidence that topoisomerase I is catalytically active on ribosomal DNA in vivo.
- Published
- 1985
- Full Text
- View/download PDF
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