13 results on '"Reddy RM"'
Search Results
2. Quality improvement mechanisms to improve lymph node staging for lung cancer: Trends from a statewide database.
- Author
-
Kalata S, Reddy RM, Norton EC, Clark MJ, He C, Leyden T, Adams KN, Popoff AM, Lall SC, and Lagisetty KH
- Subjects
- Humans, Lymph Nodes surgery, Lymph Nodes pathology, Mediastinum pathology, Neoplasm Staging, Quality Improvement, Retrospective Studies, Carcinoma, Non-Small-Cell Lung pathology, Lung Neoplasms surgery, Lung Neoplasms pathology
- Abstract
Objective: Our statewide thoracic quality collaborative has implemented multiple quality improvement initiatives to improve lung cancer nodal staging. We subsequently implemented a value-based reimbursement initiative to further incentivize quality improvement. We compare the impact of these programs to steer future quality improvement initiatives., Methods: Since 2016, our collaborative focused on improving lymph node staging for lung cancer by leveraging unblinded, hospital-level metrics and collaborative feedback. In 2021, a value-based reimbursement initiative was implemented with statewide yearly benchmark rates for (1) preoperative mediastinal staging for ≥T2N0 lung cancer, and (2) sampling ≥5 lymph node stations. Participating surgeons would receive additional reimbursement if either benchmark was met. We reviewed patients from January 2015 to March 2023 at the 21 participating hospitals to determine the differential effects on quality improvement., Results: We analyzed 6228 patients. In 2015, 212 (39%) patients had ≥5 nodal stations sampled, and 99 (51%) patients had appropriate preoperative mediastinal staging. During 2016 to 2020, this increased to 2253 (62%) patients and 739 (56%) patients, respectively. After 2020, 1602 (77%) patients had ≥5 nodal stations sampled, and 403 (73%) patients had appropriate preoperative mediastinal staging. Interrupted time-series analysis demonstrated significant increases in adequate nodal sampling and mediastinal staging before value-based reimbursement. Afterward, preoperative mediastinal staging rates briefly dropped but significantly increased while nodal sampling did not change., Conclusions: Collaborative quality improvement made significant progress before value-based reimbursement, which reinforces the effectiveness of leveraging unblinded data to a collaborative group of thoracic surgeons. Value-based reimbursement may still play a role within a quality collaborative to maintain infrastructure and incentivize participation., Competing Interests: Conflict of Interest Statement R.R. receives consulting fees from Intuitive, Genentech, AtriCure, Medtronic, and On Target Labs. All other authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (Copyright © 2023 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
3. Commentary: The importance of equity in letters of recommendation in residency and fellowship applications.
- Author
-
Reddy RM
- Published
- 2023
- Full Text
- View/download PDF
4. Pulmonary Open, Robotic, and Thoracoscopic Lobectomy study: Outcomes and risk factors of conversion during minimally invasive lobectomy.
- Author
-
Herrera LJ, Schumacher LY, Hartwig MG, Bakhos CT, Reddy RM, Vallières E, and Kent MS
- Subjects
- Humans, Male, Cohort Studies, Retrospective Studies, Pneumonectomy adverse effects, Pneumonectomy methods, Thoracic Surgery, Video-Assisted adverse effects, Thoracic Surgery, Video-Assisted methods, Risk Factors, Thoracotomy adverse effects, Thoracotomy methods, Robotic Surgical Procedures adverse effects, Robotic Surgical Procedures methods, Lung Neoplasms pathology
- Abstract
Objective: Conversion to thoracotomy continues to be a concern during minimally invasive lobectomy. The aim of this propensity-matched cohort study is to analyze the outcomes and risk factors of intraoperative conversion during video-assisted thoracoscopic surgery (VATS) and robotic lobectomy (RL)., Methods: Data from consecutive lobectomy cases performed for clinical stage IA to IIIA lung cancer was retrospectively collected from the Pulmonary Open, Robotic, and Thoracoscopic Lobectomy study consortium of 21 institutions from 2011 to 2019. The propensity-score method of inverse-probability of treatment weighting was used to balance the baseline characteristics across surgical approaches. Univariate logistic regression models were applied to test risk factors for conversion. Multivariable logistic regression analysis was conducted using a stepwise model selection method., Results: Seven thousand two hundred sixteen patients undergoing lobectomy were identified: RL (n = 2968), VATS (n = 2831), and open lobectomy (n = 1417). RL had lower conversion rate compared with VATS (3.6% vs 12.9%; P < .0001). In the multivariable regression model, tumor size and neoadjuvant therapy were the most significant risk factors for conversion, followed by prior cardiac surgery, congestive heart failure, chronic obstructive pulmonary disease, VATS approach, male gender, body mass index, and forced expiratory volume in 1 minute. Conversions for anatomical reasons were more common in VATS than RL (66.6% vs 45.6%; P = .0002); however, conversions for vascular reasons were more common in RL than VATS (24.8% vs 14%; P = .01). The rate of emergency conversions was comparable between RL and VATS (0.5% vs 0.7%; P = .25) with no intraoperative mortalities., Conclusions: Converted minimally invasive lobectomies were not associated with worse perioperative mortality compared with open lobectomy. Compared with VATS lobectomy, RL is associated with a lower probability of conversion in this propensity-score matched cohort study., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2023
- Full Text
- View/download PDF
5. Evaluation of acute and chronic pain outcomes after robotic, video-assisted thoracoscopic surgery, or open anatomic pulmonary resection.
- Author
-
Kwon ST, Zhao L, Reddy RM, Chang AC, Orringer MB, Brummett CM, and Lin J
- Subjects
- Acute Pain etiology, Adolescent, Adult, Aged, Aged, 80 and over, Chronic Pain etiology, Female, Humans, Male, Middle Aged, Pain, Postoperative etiology, Pneumonectomy adverse effects, Pneumonectomy methods, Retrospective Studies, Thoracic Surgical Procedures adverse effects, Thoracic Surgical Procedures methods, Time Factors, Young Adult, Acute Pain epidemiology, Chronic Pain epidemiology, Lung surgery, Pain, Postoperative epidemiology, Robotic Surgical Procedures adverse effects, Robotic Surgical Procedures methods, Thoracic Surgery, Video-Assisted adverse effects, Thoracic Surgery, Video-Assisted methods
- Abstract
Objectives: Although robotic-assisted thoracic surgery (RATS) provides improved dexterity, the effect of RATS on pain compared with video-assisted thoracoscopic surgery (VATS) or open lobectomy is poorly understood. This study evaluated acute and chronic pain following RATS, VATS, and open anatomic pulmonary resection., Methods: A retrospective review of 498 patients (502 procedures) who underwent RATS (74), VATS (227), and open (201) anatomic pulmonary resection including lobectomy and segmentectomy from 2010 to 2014 was performed to identify factors related to acute and chronic pain. Acute pain scores were analyzed over the first 9 postoperative days. Chronic pain was assessed using the validated PainDETECT survey., Results: There were no significant differences in acute or chronic pain between RATS and VATS. There was a significant decrease in acute pain for patients with minimally invasive surgery (P = .0004). Chronic numbness was significantly higher after open resection (25.5% vs 11.6%; P = .0269) but with no difference in other symptoms of chronic pain. Despite no significant difference in pain scores, 69.2% of patients who received RATS felt the approach affected pain versus 44.2% VATS (P = .0330). On multivariable analysis, younger age (P < .0001), female gender (P = .0364), and baseline narcotic use (P = .0142) were associated with acute pain, whereas younger age (P = .0021) and major complications (P = .0003) were associated with chronic numbness in patients who received MIS., Conclusions: Although minimally invasive approaches resulted in less acute pain and chronic numbness, there were no significant differences between RATS and VATS. In contrast, more RATS patients believed the approach affected their pain, suggesting a difference between reality and perception., (Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
6. Pulmonary venous blood sampling significantly increases the yield of circulating tumor cells in early-stage lung cancer.
- Author
-
Reddy RM, Murlidhar V, Zhao L, Grabauskiene S, Zhang Z, Ramnath N, Lin J, Chang AC, Carrott P, Lynch W, Orringer MB, Beer DG, and Nagrath S
- Subjects
- Aged, Aged, 80 and over, Early Detection of Cancer, Female, Humans, Lab-On-A-Chip Devices, Lung Neoplasms blood, Lung Neoplasms surgery, Male, Microchip Analytical Procedures, Middle Aged, Neoplasm Staging, Pneumonectomy, Predictive Value of Tests, Prospective Studies, Time Factors, Treatment Outcome, Lung Neoplasms pathology, Neoplastic Cells, Circulating pathology, Pulmonary Veins
- Abstract
Objective: To identify circulating tumor cells (CTCs) in the blood of patients with early-stage lung cancer and to show that sampling pulmonary vein (PV) blood using microfluidic chip technology will yield significantly more CTCs. Improving early detection of lung cancer is critical to improving lung cancer survival. Reproducible detection of CTCs is limited currently in early stage tumors., Methods: Patients undergoing pulmonary resection had PV blood drawn before resection. Peripheral blood was sampled at preoperative, intraoperative, and postoperative times. Samples were analyzed on microfluidic chips using antibody-based capture., Results: A total of 32 patients with primary lung cancer were evaluated. Twenty patients had 1 or more CTCs detected in at least 1 sample (62.5%). The mean number of CTCs from peripheral vein sources at the preoperative, intraoperative, and postoperative time points was 1.3, 1.9, and 0.6 respectively. The average number of CTCs in the PV was 340.0 (range, 0.0-5422.50; P > .01). When PV CTCs were present, the number of CTCs was correlated with pathological tumor size (P = .0236). The number of PV CTCs was not correlated with any other clinical feature (eg, smoking status, preoperative or postoperative stage). Furthermore, the number of PV CTCs was significantly higher when preoperative bronchoscopic biopsy was performed, compared with computed tomography-guided biopsy (P = .0311). Seven patients had evidence of CTC clusters, or microemboli., Conclusions: With a single vein draining the entire tumor basin, lung cancers are unique, allowing the high-yield isolation of CTCs from the PV. This method may facilitate future studies to improve the detection and analysis of early-stage lung CTCs., (Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
7. Endoscopic ultrasound is inadequate to determine which T1/T2 esophageal tumors are candidates for endoluminal therapies.
- Author
-
Bergeron EJ, Lin J, Chang AC, Orringer MB, and Reddy RM
- Subjects
- Adult, Aged, Aged, 80 and over, Carcinoma mortality, Carcinoma secondary, Catheter Ablation, Esophageal Neoplasms mortality, Esophageal Neoplasms pathology, Female, Hospital Mortality, Hospitals, High-Volume, Humans, Lymphatic Metastasis, Male, Michigan, Middle Aged, Neoplasm Invasiveness, Neoplasm Staging, Patient Selection, Postoperative Complications mortality, Postoperative Complications therapy, Predictive Value of Tests, Retrospective Studies, Risk Factors, Time Factors, Treatment Outcome, Carcinoma diagnostic imaging, Carcinoma surgery, Decision Support Techniques, Endosonography, Esophageal Neoplasms diagnostic imaging, Esophageal Neoplasms surgery, Esophagectomy adverse effects, Esophagectomy mortality
- Abstract
Objectives: Esophageal endoscopic ultrasound is now regarded as essential in the staging of esophageal carcinoma. There is an increasing trend toward endoluminal therapies (ie, endoscopic mucosal resection and radiofrequency ablation) for pre-cancer or early-stage cancers because of concerns of high morbidity associated with esophagectomy. This study reviews our institutional experience with preoperative endoscopic ultrasound staging of early esophageal cancers in patients who underwent an esophagectomy to evaluate the accuracy of staging by endoscopic ultrasound and how this affects treatment recommendations., Methods: A prospective esophagectomy database of all patients undergoing an esophagectomy for esophageal cancer at a single high-volume institution was retrospectively reviewed for patients with early-stage esophageal cancer. This study analyzed patients with clinical Tis to T1 disease, as predicted by preoperative endoscopic ultrasound, and correlated this with the pathologic stages after esophagectomy. The surgical outcomes were evaluated to assess the safety of esophagectomy as a treatment modality., Results: From 2005 to 2011, 107 patients (93 male, 14 female) with a mean age of 66 years (range, 39-91 years) were staged by preoperative endoscopic ultrasound to have esophageal high-grade dysplasia, carcinoma in situ, or T1 cancer and underwent an esophagectomy. Tumor depth was correctly staged by endoscopic ultrasound in only 39% (23/59) of pT1a tumors (invading into the lamina propria or muscularis mucosa) and 51% (18/35) of pT1b tumors (submucosal). Of the endoscopic ultrasound-staged cT1a-lpN0 lesions, there were positive lymph nodes in 15% of pathologic specimens (2/13). Patients with pT1a-mm lesions had a 9% rate of pathologic lymph node involvement (1/11), and those with pT1b tumors had a 17% rate of lymph node spread (6/35). Esophagectomy was performed in all 107 patients with a 30-day mortality rate of less than 1% (1/107)., Conclusions: The sensitivity and specificity of endoscopic ultrasound for determining true pathologic staging are poor for early-stage esophageal cancers. Lesions thought to be cT1a-lpN0 by endoscopic ultrasound have at least pN1 disease in 15% of cases. Endoluminal therapy of these lesions based on endoscopic ultrasound undertreats a significant number of patients. Esophagectomy is still the standard therapy for early-stage esophageal cancers in the majority of patients., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
8. "Back to the future": recruiting the best and brightest into cardiothoracic surgery.
- Author
-
Kim AW, Reddy RM, and Higgins RS
- Subjects
- Education, Medical, Graduate, Humans, Internship and Residency, Job Satisfaction, Mentors, Personnel Selection, Societies, Medical, United States, Cardiovascular Surgical Procedures education, Career Choice, Thoracic Surgery education, Thoracic Surgical Procedures education
- Published
- 2010
- Full Text
- View/download PDF
9. Contralateral papillary thyroid cancer at completion thyroidectomy has no impact on recurrence or survival after radioiodine treatment.
- Author
-
Grigsby PW, Reddy RM, Moley JF, and Hall BL
- Subjects
- Adolescent, Adult, Aged, Carcinoma, Papillary radiotherapy, Carcinoma, Papillary surgery, Child, Combined Modality Therapy, Female, Humans, Iodine Radioisotopes therapeutic use, Male, Middle Aged, Neoplasm Staging, Predictive Value of Tests, Prognosis, Regression Analysis, Retrospective Studies, Risk Factors, Survival Rate, Thyroid Neoplasms radiotherapy, Thyroid Neoplasms surgery, Carcinoma, Papillary pathology, Neoplasm Recurrence, Local, Radiotherapy methods, Thyroid Neoplasms pathology, Thyroidectomy
- Abstract
Background: This study investigated the rate of contralateral papillary thyroid cancer (PTC) in low-risk PTC patients who had completion thyroidectomy, and were referred for radioactive iodine (RAI) therapy. The study sought predictors of contralateral disease and examined the impact of contralateral disease in RAI-treated patients., Methods: We reviewed 20 years of data from a prospective registry for 150 patients with PTC. These patients had undergone thyroid lobectomy, followed by completion thyroidectomy, and had been referred for RAI., Results: Of the 150 patients, 41% had PTC in the contralateral lobe. There was no difference in the rate of contralateral disease in low-risk patients (age <45 years, T1 tumors, lymph node-negative) compared with the remainder. There were no significant differences between patients with or without contralateral disease with respect to primary tumor size, mean age, time to completion thyroidectomy, or metastatic lymph node disease. Logistic regression analyses showed no histologic parameters that correlated with contralateral disease. There were no recurrence or survival differences in patients with or without contralateral disease after resection and RAI., Conclusions: The prevalence of tumor in the contralateral lobe of low-risk patients with PTC is significant and warrants consideration for completion thyroidectomy and radioiodine treatment. Our results, however, suggest that contralateral disease does not have an impact on recurrence or survival after treatment.
- Published
- 2006
- Full Text
- View/download PDF
10. Lymph node metastases in differentiated thyroid cancer under 2 cm.
- Author
-
Reddy RM, Grigsby PW, Moley JF, and Hall BL
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Cell Transformation, Neoplastic, Child, Child, Preschool, Female, Humans, Lymphatic Metastasis diagnosis, Male, Middle Aged, Neoplasm Recurrence, Local mortality, Neoplasm Staging, Prognosis, Prospective Studies, Survival Rate, Thyroid Neoplasms mortality, Thyroidectomy, Lymphatic Metastasis pathology, Thyroid Neoplasms pathology
- Abstract
Background: The goal of this study was to evaluate the presence of lymph node metastasis in patients with T1 differentiated thyroid cancer (DTC) and determine prognostic significance for tumor recurrence and cancer-related death., Methods: From a prospective tumor registry, we reviewed data from 551 patients with DTC who underwent total or subtotal thyroidectomy and who had primary tumor size =2 cm. Patients received standard radioactive iodine ablation., Results: The proportion of patients with lymph node metastasis was 45%. This percentage remained the same in a comparison of tumors from 0 to 1 cm with tumors from 1 to 2 cm. Logistic regression analyses did not identify primary tumor size as a predictor of lymph node metastasis, but did show that histologic vascular invasion and soft tissue invasion correlated with positive lymph nodes. Multifocal disease approached significance. Actuarial estimates for first recurrence displayed a significant difference in patients who had positive cervical lymph nodes versus negative nodes: 56% versus 71% disease-free at 20 years. There was no difference in cancer-related death., Conclusions: In T1 DTC, lymph node metastasis does not correlate with tumor size but does correlate with vascular/soft tissue invasion. Patients with positive lymph nodes have a higher recurrence risk, but no significant increase in death.
- Published
- 2006
- Full Text
- View/download PDF
11. The selective epidermal growth factor receptor tyrosine kinase inhibitor PD153035 suppresses expression of prometastasis phenotypes in malignant pleural mesothelioma cells in vitro.
- Author
-
Cole GW Jr, Alleva AM, Reddy RM, Maxhimer JB, Zuo J, Schrump DS, and Nguyen DM
- Subjects
- Antineoplastic Agents pharmacology, Cell Movement drug effects, Cell Proliferation drug effects, Cocarcinogenesis, Collagen, Dose-Response Relationship, Drug, Drug Combinations, Drug Screening Assays, Antitumor, Enzyme-Linked Immunosorbent Assay, ErbB Receptors analysis, ErbB Receptors genetics, Flow Cytometry, Fluorescent Antibody Technique, Indirect, Gene Expression Regulation, Neoplastic genetics, Humans, Laminin, Neoplasm Invasiveness, Neoplasm Metastasis genetics, Neoplasm Metastasis prevention & control, Phenotype, Proteoglycans, Quinazolines pharmacokinetics, Signal Transduction drug effects, Signal Transduction genetics, Tumor Cells, Cultured physiology, Tumor Stem Cell Assay, Vascular Endothelial Growth Factor A analysis, Vascular Endothelial Growth Factor A drug effects, Antineoplastic Agents therapeutic use, ErbB Receptors antagonists & inhibitors, Gene Expression Regulation, Neoplastic drug effects, Mesothelioma drug therapy, Pleural Neoplasms drug therapy, Quinazolines therapeutic use, Tumor Cells, Cultured drug effects
- Abstract
Objective: Malignant pleural mesothelioma is notoriously refractory to aggressive multimodality therapy. Epidermal growth factor receptor expression has been observed on malignant pleural mesothelioma cells. Epidermal growth factor receptor-mediated signaling promotes tumorigenesis and metastasis of cancer cells. The purpose of this study is to evaluate the ability of the epidermal growth factor receptor tyrosine kinase inhibitor PD153035 to abrogate the expression of prometastasis phenotypes in malignant pleural mesothelioma cells in vitro., Methods: Epidermal growth factor receptor expression of malignant pleural mesothelioma cells and primary normal cells was quantitated by means of flow cytometry. PD153035-mediated growth inhibition was determined by means of 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan and clonogenic assays. Cell motility and invasion of extracellular matrix was evaluated with in vitro wound-healing and Matrigel invasion assays, respectively. Vascular epidermal growth factor levels in conditioned media were measured by using enzyme-linked immunosorbent assay., Results: Epidermal growth factor receptor expression was detected on all 6 cultured malignant pleural mesothelioma cells, with 4 of 6 having normal receptor expression and 2 of 6 overexpressing the receptor. PD153035 suppressed cell motility and cell invasion through a Matrigel membrane, regardless of the baseline epidermal growth factor receptor expression. Decreased vascular epidermal growth factor production and significant inhibition of growth only occurred in malignant pleural mesothelioma cells that overexpress epidermal growth factor receptor., Conclusions: Epidermal growth factor receptor tyrosine kinase inhibitor PD153035 significantly inhibited motility and invasion in malignant pleural mesothelioma cells in vitro, regardless of their epidermal growth factor receptor expression levels. Inhibition of epidermal growth factor receptor-dependent signaling might be a useful strategy to diminish malignant pleural mesothelioma recurrence after aggressive cytoreductive surgery.
- Published
- 2005
- Full Text
- View/download PDF
12. Induction of apoptosis of lung and esophageal cancer cells treated with the combination of histone deacetylase inhibitor (trichostatin A) and protein kinase C inhibitor (calphostin C).
- Author
-
Maxhimer JB, Reddy RM, Zuo J, Cole GW, Schrump DS, and Nguyen DM
- Subjects
- Blotting, Western, Cell Proliferation drug effects, Cell Survival drug effects, Drug Therapy, Combination, Esophageal Neoplasms drug therapy, Esophageal Neoplasms pathology, Histone Deacetylase Inhibitors, Humans, Lung Neoplasms drug therapy, Lung Neoplasms pathology, NF-kappa B drug effects, Oncogene Protein p21(ras) drug effects, Probability, Protein Kinase C antagonists & inhibitors, Risk Factors, Sensitivity and Specificity, Tumor Cells, Cultured, Up-Regulation, Apoptosis drug effects, Hydroxamic Acids pharmacology, NF-kappa B metabolism, Naphthalenes pharmacology, Oncogene Protein p21(ras) metabolism
- Abstract
Objective: Histone deacetylase inhibitors mediate a potent growth-inhibitory effect in cancer cells through induction of cell-cycle arrest and apoptosis. Moreover, these agents significantly induce transcriptional activation of nuclear factor kappaB, as well as p21 regulated by protein kinase C, and are thought to negatively influence the ability of histone deacetylase inhibitor to effectively mediate apoptosis. This study aimed to evaluate the effect of calphostin C (a protein kinase C inhibitor) on trichostatin A (a histone deacetylase inhibitor)-mediated upregulation of nuclear factor kappaB and p21 promotor transcriptional activity, as well as induction of apoptosis in lung and esophageal cancer cells., Methods: Cultured lung and esophageal cancer cells were treated with calphostin C and trichostatin A. Nuclear factor kappaB transcriptional activity was quantitated by using the nuclear factor kappaB-luciferase assay. Transcription of p21 gene and p21 protein levels was evaluated by using the p21 promoter-luciferase assay and the p21 enzyme-linked immunoassay, respectively. Apoptosis was evaluated by using the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling-based ApoBrdU assay. Levels of expression of nuclear factor kappaB-dependent antiapoptotic and proapoptotic proteins were evaluated by means of Western blotting., Results: Exposure of lung or esophageal cancer cells to trichostatin A resulted in a dose- and cell-dependent 2-fold to greater than 20-fold increase of nuclear factor kappaB and p21 transcriptional activity. Treatment with trichostatin A and calphostin C led to a 50% to 90% decrease of trichostatin A- mediated upregulation of nuclear factor kappaB and p21 activation. Inhibition of nuclear factor kappaB activity resulted in significant reduction (30% to >99%) of trichostatin A- mediated activation of not only nuclear factor kappaB transcription but also p21 promotor activity. Importantly, 90% to 96% of thoracic cancer cells under-went apoptosis after exposure to the combination of trichostatin A plus calphostin C., Conclusion: Inhibition of protein kinase C abrogates trichostatin A-mediated upregulation of nuclear factor kappaB transcriptional activity and p21 expression that is associated with profound induction of apoptosis in lung or esophageal cancer cells. Protein kinase C might be a novel target for enhancing the efficacy of histone deacetylase inhibitor in cancer therapy.
- Published
- 2005
- Full Text
- View/download PDF
13. Cisplatin enhances apoptosis induced by a tumor-selective adenovirus expressing tumor necrosis factor-related apoptosis-inducing ligand.
- Author
-
Reddy RM, Tsai WS, Ziauddin MF, Zuo J, Cole GW Jr, Maxhimer JB, Fang B, Schrump DS, and Nguyen DM
- Subjects
- Adenoviridae, Apoptosis Regulatory Proteins, Carcinoma, Non-Small-Cell Lung metabolism, Dose-Response Relationship, Drug, Flow Cytometry, Genetic Vectors, Green Fluorescent Proteins, Humans, Ligands, Lung Neoplasms metabolism, Receptors, TNF-Related Apoptosis-Inducing Ligand, Receptors, Tumor Necrosis Factor metabolism, TNF-Related Apoptosis-Inducing Ligand, Tumor Cells, Cultured, Tumor Necrosis Factor-alpha biosynthesis, Antineoplastic Agents pharmacology, Apoptosis drug effects, Cisplatin pharmacology, Membrane Glycoproteins drug effects, Tumor Necrosis Factor-alpha drug effects
- Abstract
Background: Cancer cells frequently exhibit resistance to the cytotoxic effect of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Pretreatment of TRAIL-resistant cells with cisplatin sensitizes them to this ligand. Cisplatin also has been shown to enhance adenoviral transgene expression., Objective: This study aims to evaluate the ability of cisplatin to enhance the expression and the cytotoxic effect of the tumor-specific adenoviral vector Ad/gTRAIL, which expresses a green fluorescent protein-TRAIL fusion protein., Methods: Cultured cancer cells and normal human cells were infected with Ad/gTRAIL with or without cisplatin pretreatment. Adenoviral transgene expression was determined by using flow cytometry to measure green fluorescent protein fluorescence. Cytotoxicity was measured by using thiazolyl blue tetrazolium bromide assays and an apoptosis enzyme-linked immunosorbent assay kit., Results: Green fluorescent protein-TRAIL fusion protein expression was significantly enhanced by cisplatin pretreatment in cancer cells. Cisplatin treatment before Ad/gTRAIL infection resulted in a 2- to 12-fold increase in green fluorescent protein fluorescence intensity across cancer lines. Although Ad/gTRAIL induced mild cytotoxicity in all cancer lines (inhibitory concentration of 50% values of >500 pfu/cell), pretreatment with cisplatin resulted in a dose-dependent enhancement of Ad/gTRAIL-mediated cytotoxicity, as indicated by the drastic reduction of inhibitory concentration of 50% values to 4 to 42 pfu/cell in all cell lines. There was no cytotoxicity noted in normal cells treated with both cisplatin and Ad/gTRAIL., Conclusion: Cisplatin pretreatment enhances Ad/gTRAIL cytotoxicity in malignant cells while not affecting normal cells. The mechanisms underlying this effect might include both enhancement of the susceptibility of cisplatin-treated cells to TRAIL and cisplatin-mediated enhancement of TRAIL expression in Ad/gTRAIL infected cells. These findings provide a rationale for development of Ad/gTRAIL-based therapy for thoracic malignancies.
- Published
- 2004
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.