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Contieri R, Grajales V, Tan WS, Martini A, Sood A, Hensley P, Bree K, Lobo N, Nogueras-Gonzalez GM, Guo CC, Navai N, Dinney CP, Kamat AM. Impact of age >70 years on oncological outcomes in patients with non-muscle-invasive bladder cancer treated with Bacillus Calmette-Guérin. BJU Int 2024; 133:63-70. [PMID: 37442564 PMCID: PMC10787034 DOI: 10.1111/bju.16127] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2023]
Abstract
OBJECTIVE To evaluate the impact of age on oncological outcomes in a large contemporary cohort of patients with non-muscle-invasive bladder cancer (NMIBC) treated with adequate Bacillus Calmette-Guérin (BCG). PATIENTS AND METHODS We performed an Institutional Review Board-approved retrospective study analysing patients with NMIBC treated with adequate BCG at our institution from 2000 to 2020. Adequate BCG was defined as per United States Food and Drug Administration (FDA) guidelines as being receipt of at least five of six induction BCG instillations with a minimum of two additional doses (of planned maintenance or of re-induction) of BCG instillations within a span of 6 months. The study's primary outcome was to determine if age >70 years was associated with progression to MIBC cancer or distant metastasis. The cumulative incidence method and the competing-risk regression analyses were used to investigate the association of advanced age (>70 years) with progression, high-grade (HG) recurrence and cancer-specific mortality (CSM). RESULTS Overall, data from 632 patients were analysed: 355 patients (56.2%) were aged ≤70 years and 277 (43.8%) were >70 years. Age >70 years did not adversely affect either cumulative incidence of progression or HG recurrence (P = 0.067 and P = 0.644, respectively). On competing-risk regression analyses, age >70 years did not emerge as an independent predictor of progression or HG recurrence (sub-standardised hazard ratio [SHR] 1.57, 95% confidence interval [CI] 0.87-2.81, P = 0.134; and SHR 1.05, 95% CI 0.77-1.44, P = 0.749). Not unexpectedly, patients in the older group did have higher overall mortality (P < 0.001) but not CSM (P = 0.057). CONCLUSION Age >70 years was not associated with adverse oncological outcomes in a large contemporary cohort of patients receiving adequate intravesical BCG for NMIBC. BCG should not be withheld from older patients seeking for bladder sparing options.
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Affiliation(s)
- Roberto Contieri
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Humanitas University, Milan, Italy
| | - Valentina Grajales
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Wei Shen Tan
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Alberto Martini
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Akshay Sood
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Patrick Hensley
- Department of Urology, University of Kentucky, Lexington, KY, USA
| | - Kelly Bree
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Niyati Lobo
- Department of Urology, Guy's and St Thomas NHS Foundation Trust, London, United Kingdom of Great Britain and Northern Ireland
| | | | - Charles C Guo
- Department of Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Neema Navai
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Colin P Dinney
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ashish M Kamat
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
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2
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Saltzman AF, Hensley P, Ross J, Woo L, Billmire D, Rescorla F, Puri D, Patel S, Pierorazio P, Bagrodia A, Cary C, Cost NG. Critical elements of pediatric testicular germ cell tumors surgery. Semin Pediatr Surg 2023; 32:151343. [PMID: 38006835 DOI: 10.1016/j.sempedsurg.2023.151343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2023]
Abstract
Children, adolescents and young adults with testicular germ cell tumors require appropriate surgical care to insure excellent outcomes. This article presents the most critical elements, and their basis in evidence, for surgery in this population. Specifically, the importance of inguinal radical orchiectomy for malignant tumors, partial orchiectomy for prepubertal tumors and normal serum tumor markers, and the appropriate use of post-chemotherapy retroperitoneal lymph node dissection in those with residual retroperitoneal masses.
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Affiliation(s)
| | - Patrick Hensley
- Department of Urology, University of Kentucky, Lexington, KY, USA
| | - Jonathan Ross
- Department of Urology, Rush University, Chicago, IL, USA
| | - Lynn Woo
- Department of Urology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Deborah Billmire
- Department of Pediatric Surgery, Indiana University School of Medicine and Riley Hospital for Children at Indiana University Health, Indianapolis, IN, USA
| | - Frederick Rescorla
- Department of Pediatric Surgery, Indiana University School of Medicine and Riley Hospital for Children at Indiana University Health, Indianapolis, IN, USA
| | - Dhruv Puri
- Department of Urology, University of California San Diego, La Jolla, CA, USA
| | - Sunil Patel
- Department of Urology, The James Buchanan Brady Urological Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | | | - Aditya Bagrodia
- Department of Urology, University of California San Diego, La Jolla, CA, USA
| | - Clint Cary
- Department of Urology, Indiana University, Indianapolis, IN, USA
| | - Nicholas G Cost
- Division of Urology, Department of Surgery at the University of Colorado School of Medicine, Aurora, CO, USA; The Surgical Oncology Program, Children's Hospital Colorado, Aurora, CO, USA.
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3
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Makaroff LE, Filicevas A, Boldon S, Hensley P, Black PC, Chisolm S, Demkiw S, Fernández MI, Sugimoto M, Jensen BT, Witjes WPJ, Bagshaw K, Cirefice-Funk L, Knight A, Kamat AM. Patient and Carer Experiences with Bladder Cancer: Results from a Global Survey in 45 Countries. Eur Urol 2023; 84:248-251. [PMID: 37236857 DOI: 10.1016/j.eururo.2023.04.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 04/08/2023] [Accepted: 04/28/2023] [Indexed: 05/28/2023]
Affiliation(s)
- Lydia E Makaroff
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Fight Bladder Cancer UK, Oxford, UK
| | - Alex Filicevas
- World Bladder Cancer Patient Coalition, Brussels, Belgium
| | - Shannon Boldon
- World Bladder Cancer Patient Coalition, Brussels, Belgium
| | - Patrick Hensley
- Department of Urology, University of Kentucky, Lexington, KY, USA; International Bladder Cancer Group (1)
| | - Peter C Black
- International Bladder Cancer Group (1); Department of Urologic Sciences, Vancouver Prostate Centre, University of British Columbia, Vancouver, Canada; International Bladder Cancer Network (2); Société Internationale d'Urologie, Montreal, Canada; Bladder Cancer Canada, Toronto, Canada
| | - Stephanie Chisolm
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Bladder Cancer Advocacy Network, Bethesda, MD, USA
| | - Stephanie Demkiw
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Bladder Cancer Awareness Australia, Melbourne, Australia; Access Health and Community, Melbourne, Australia
| | - Mario I Fernández
- International Bladder Cancer Group (1); Department of Urology, Clínica Alemana Universidad del Desarrollo, Santiago, Chile
| | - Mikio Sugimoto
- Department of Urology, Kagawa University Hospital, Kagawa, Japan
| | | | - Wim P J Witjes
- European Association of Urology Research Foundation, Arnhem, The Netherlands
| | - Ken Bagshaw
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Bladder Cancer Canada, Toronto, Canada
| | - Lori Cirefice-Funk
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Cancer Vessie France, Aix-en-Provence, France
| | - Allen Knight
- World Bladder Cancer Patient Coalition, Brussels, Belgium; Action Bladder Cancer, Gloucestershire, UK
| | - Ashish M Kamat
- World Bladder Cancer Patient Coalition, Brussels, Belgium; International Bladder Cancer Group (1); International Bladder Cancer Network (2); Société Internationale d'Urologie, Montreal, Canada; Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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4
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Tan WS, Grajales V, Contieri R, Hensley P, Bree K, Msaouel P, Guo CC, Nogueras-Gonzalez GM, Navai N, Dinney CP, Kamat AM. Bladder-sparing Treatment in Patients with Bacillus Calmette-Guerin-unresponsive Non-muscle-invasive Bladder Cancer: An Analysis of Long-term Survival Outcomes. EUR UROL SUPPL 2023; 53:16-22. [PMID: 37441349 PMCID: PMC10334230 DOI: 10.1016/j.euros.2023.04.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/20/2023] [Indexed: 07/15/2023] Open
Abstract
Background Data for bladder-sparing treatment (BST) in bacillus Calmette-Guerin (BCG)-unresponsive non-muscle-invasive bladder cancer (NMIBC) patients report short-term outcomes limited to 1-2 yr. Objective To assess long-term survival outcomes of BCG-unresponsive NMIBC patients treated with BST. Design setting and participants BCG-unresponsive NMIBC patients diagnosed between January 2000 and September 2021 from an institutional NMIBC registry were evaluated. Intervention Long-term survival outcomes for patients receiving BST, early radical cystectomy (RC), and delayed RC were compared. Outcome measurements and statistical analysis The primary endpoints were overall survival (OS) and cancer-specific survival (CSS). Results and limitations In total, 114 patients with a median follow-up of 71.2 mo (interquartile range: 32.6-132.2) were analyzed. There were no significant differences in OS (hazard ratio [HR]: 1.40, 95% confidence interval [CI]: 0.68-2.89, p = 0.4) or CSS (HR: 0.88, 95% CI: 0.22-3.55, p = 0.9) between patients undergoing early RC (n = 38) and BST (n = 76). At 60 mo, BST patients had a high-grade recurrence-free rate, muscle-invasive disease/metastasis progression-free rate, and avoidance of RC rate of 37%, 83%, and 58%, respectively. Current smoker status (HR: 4.44, 95% CI: 1.41-13.97, p = 0.011) was the only variable predictive of high-grade recurrence following a multivariable analysis. The median time to RC from BCG-unresponsive date was 2.1 and 11.7 mo for those undergoing early RC and delayed RC (after BST), respectively. Patients treated with early RC had a higher incidence of cT1 disease (53% vs 36%, p = 0.049) and lymphovascular invasion (LVI; 11% vs 0%, p = 0.011) compared to patients treated with BST. Survival outcomes were similar between groups: 10-yr OS-58% versus 50% (HR: 1.40, 95% CI: 0.68-2.89, p = 0.4), and 10-yr CSS-81% versus 85% (HR: 0.88, 95% CI: 0.22-3.55, p = 0.9). Conclusions An analysis of long-term survival of BCG-unresponsive NMIBC patients receiving BST suggests that it may be safe in patients without LVI and/or variant histology and nonsmokers. Survival outcomes for patients treated with BST may not be inferior to those receiving early RC. Patient summary Bladder-sparing treatment can be offered to appropriately selected patients who have bacillus Calmette-Guerin (BCG)-unresponsive non-muscle-invasive bladder cancer. Long-term outcomes may not be inferior to those for patients who opt for early radical cystectomy.
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Affiliation(s)
- Wei Shen Tan
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Valentina Grajales
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Roberto Contieri
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Patrick Hensley
- Department of Urology, University of Kentucky, Lexington, KY, USA
| | - Kelly Bree
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Pavlos Msaouel
- Department of Genitourinary Medical Oncology, Division of Cancer Medicine, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Charles C. Guo
- Department of Genitourinary Pathology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | | | - Neema Navai
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Colin P. Dinney
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ashish M. Kamat
- Department of Urology, University of Texas MD Anderson Cancer Center, Houston, TX, USA
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Gallagher K, Bhatt N, Clement K, Zimmermann E, Khadhouri S, MacLennan S, Kulkarni M, Gaba F, Anbarasan T, Asif A, Light A, Ng A, Chan V, Nathan A, Cooper D, Aucott L, Marcq G, Teoh JYC, Hensley P, Duncan E, Goulao B, O'Brien T, Nielsen M, Mariappan P, Kasivisvanathan V. Audit, Feedback, and Education to Improve Quality and Outcomes in Transurethral Resection and Single-Instillation Intravesical Chemotherapy for Nonmuscle Invasive Bladder Cancer Treatment: Protocol for a Multicenter International Observational Study With an Embedded Cluster Randomized Trial. JMIR Res Protoc 2023; 12:e42254. [PMID: 37318875 DOI: 10.2196/42254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 03/17/2023] [Accepted: 03/22/2023] [Indexed: 06/17/2023] Open
Abstract
BACKGROUND Nonmuscle invasive bladder cancer (NMIBC) accounts for 75% of bladder cancers. It is common and costly. Cost and detriment to patient outcomes and quality of life are driven by high recurrence rates and the need for regular invasive surveillance and repeat treatments. There is evidence that the quality of the initial surgical procedure (transurethral resection of bladder tumor [TURBT]) and administration of postoperative bladder chemotherapy significantly reduce cancer recurrence rates and improve outcomes (cancer progression and mortality). There is surgeon-reported evidence that TURBT practice varies significantly across surgeons and sites. There is limited evidence from clinical trials of intravesical chemotherapy that NMIBC recurrence rate varies significantly between sites and that this cannot be accounted for by differences in patient, tumor, or adjuvant treatment factors, suggesting that how the surgery is performed may be a reason for the variation. OBJECTIVE This study primarily aims to determine if feedback on and education about surgical quality indicators can improve performance and secondarily if this can reduce cancer recurrence rates. Planned secondary analyses aim to determine what surgeon, operative, perioperative, institutional, and patient factors are associated with better achievement of TURBT quality indicators and NMIBC recurrence rates. METHODS This is an observational, international, multicenter study with an embedded cluster randomized trial of audit, feedback, and education. Sites will be included if they perform TURBT for NMIBC. The study has four phases: (1) site registration and usual practice survey; (2) retrospective audit; (3) randomization to audit, feedback, and education intervention or to no intervention; and (4) prospective audit. Local and national ethical and institutional approvals or exemptions will be obtained at each participating site. RESULTS The study has 4 coprimary outcomes, which are 4 evidence-based TURBT quality indicators: a surgical performance factor (detrusor muscle resection); an adjuvant treatment factor (intravesical chemotherapy administration); and 2 documentation factors (resection completeness and tumor features). A key secondary outcome is the early cancer recurrence rate. The intervention is a web-based surgical performance feedback dashboard with educational and practical resources for TURBT quality improvement. It will include anonymous site and surgeon-level peer comparison, a performance summary, and targets. The coprimary outcomes will be analyzed at the site level while recurrence rate will be analyzed at the patient level. The study was funded in October 2020 and began data collection in April 2021. As of January 2023, there were 220 hospitals participating and over 15,000 patient records. Projected data collection end date is June 30, 2023. CONCLUSIONS This study aims to use a distributed collaborative model to deliver a site-level web-based performance feedback intervention to improve the quality of endoscopic bladder cancer surgery. The study is funded and projects to complete data collection in June 2023. TRIAL REGISTRATION ClinicalTrials.org NCT05154084; https://clinicaltrials.gov/ct2/show/NCT05154084. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID) DERR1-10.2196/42254.
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Affiliation(s)
- Kevin Gallagher
- Department of Urology, Western General Hospital Edinburgh, Edinburgh, United Kingdom
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - Nikita Bhatt
- British Urology Researchers in Surgical Training, London, United Kingdom
- Department of Urology, Norfolk and Norwich University Hospital, Norwich, United Kingdom
| | - Keiran Clement
- British Urology Researchers in Surgical Training, London, United Kingdom
- Department of Urology, National Health Service Greater Glasgow and Clyde, Glasgow, United Kingdom
| | - Eleanor Zimmermann
- British Urology Researchers in Surgical Training, London, United Kingdom
- Department of Urology, University Hospitals Plymouth, Plymouth, United Kingdom
| | - Sinan Khadhouri
- British Urology Researchers in Surgical Training, London, United Kingdom
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Steven MacLennan
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Meghana Kulkarni
- British Urology Researchers in Surgical Training, London, United Kingdom
- Department of Urology, St. George's University Hospital London, London, United Kingdom
| | - Fortis Gaba
- British Urology Researchers in Surgical Training, London, United Kingdom
- Harvard Business School, Harvard University, Boston, MA, United States
| | - Thineskrishna Anbarasan
- British Urology Researchers in Surgical Training, London, United Kingdom
- Oxford University Hospitals, Oxford, United Kingdom
| | - Aqua Asif
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - Alexander Light
- British Urology Researchers in Surgical Training, London, United Kingdom
- Department of Surgery and Cancer, Imperial College London, London, United Kingdom
| | - Alexander Ng
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - Vinson Chan
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - Arjun Nathan
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
| | - David Cooper
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Lorna Aucott
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Gautier Marcq
- Urology Department, Claude Huriez Hospital, Centre Hospitalier Universitaire de Lille, Lille, France
- Cancer Heterogeneity Plasticity and Resistance to Therapies, Institute Pasteur de Lille, University of Lille, Lille, France
| | - Jeremy Yuen-Chun Teoh
- S H Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, Hong Kong
| | - Patrick Hensley
- Department of Urology, College of Medicine, University of Kentucky, Lexington, KY, United States
| | - Eilidh Duncan
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Beatriz Goulao
- Health Services Research Unit, University of Aberdeen, Aberdeen, United Kingdom
| | - Tim O'Brien
- Department of Urology, Guy's and St. Thomas' National Health Service Foundation Trust, London, United Kingdom
| | - Matthew Nielsen
- Department of Urology, University of North Carolina Medical School, Chapel Hill, NC, United States
| | - Paramananthan Mariappan
- Edinburgh Bladder Cancer Surgery, Department of Urology, Western General Hospital Edinburgh, Edinburgh, United Kingdom
| | - Veeru Kasivisvanathan
- British Urology Researchers in Surgical Training, London, United Kingdom
- Division of Surgery and Interventional Science, University College London, London, United Kingdom
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6
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Contieri R, Hensley P, Grajales V, Tan W, Bree K, Guo C, Nogueras-Gonzalez G, Navai N, Dinney C, Kamat A. Bacillus calmette-guerin vs immediate radical cystectomy in eau defined very high-risk non-muscle invasive bladder cancer patients. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00766-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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7
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Sood A, Keeley J, Palma-Zamora I, Novara G, Elshaikh M, Jeong W, Hensley P, Navai N, Peabody JO, Trinh QD, Rogers CG, Menon M, Abdollah F. High-intensity local treatment of clinical node-positive urothelial carcinoma of the bladder alongside systemic chemotherapy improves overall survival. Urol Oncol 2021; 40:62.e1-62.e11. [PMID: 34348860 DOI: 10.1016/j.urolonc.2021.07.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 07/05/2021] [Accepted: 07/14/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE Clinical node-positive urothelial carcinoma of the bladder (cN+UCaB) is a rapidly fatal disease with limited information on comparative-effectiveness of available treatment options. We sought to examine the impact of high-intensity vs. conservative local treatment (LT) regimens in management of these patients alongside systemic chemotherapy. MATERIALS AND METHODS We identified 3,227 patients within the National Cancer Data Base who underwent multiagent systemic chemotherapy along with either high-intensity or conservative LT for primary cN+UCaB between 2004-2016. Patients who received no LT, TURBT alone, or <50 Gy radiation therapy to the bladder were included in the conservative group, while patients that received radical cystectomy with pelvic lymphadenectomy or ≥50 Gy radiation therapy with TURBT were included in the high-intensity group. Inverse probability of treatment weighting (IPTW) adjusted Kaplan-Meier and Cox regression analyses were used to assess overall survival (OS). Additionally, to assess whether the benefit of high-intensity LT differs by baseline mortality risk, we tested an interaction between 5-year predicted life-expectancy and the LT type. RESULTS Overall, 784 (24.3%) and 2,443 (75.7%) cN+UCaB patients underwent high-intensity and conservative LT, respectively. IPTW-adjusted Kaplan-Meier analysis demonstrated OS to be significantly higher in the high-intensity group compared to the conservative group: 5-year OS 28.4% vs. 18.3%, respectively (Log-rank P<0.001). IPTW-adjusted multivariable Cox regression analysis confirmed the benefit of high-intensity LT in prolonging OS (HR 0.63, P<0.001). Interaction analysis showed that high-intensity LT approach was associated with longer OS in all patients regardless of their baseline 5-year life-expectancy (Pinteraction=0.79). CONCLUSION Eligible patients with cN+UCaB should be considered for aggressive local treatment alongside multiagent systemic chemotherapy. Prospective trials are needed to validate these preliminary findings.
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Affiliation(s)
- Akshay Sood
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan; Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan; Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, Texas.
| | - Jacob Keeley
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan
| | | | - Giacomo Novara
- Department of Surgery, Oncology and Gastroenterology-Urology, University Hospital of Padova, Padova, Italy
| | - Mohamed Elshaikh
- Department of Radiation Oncology, Henry Ford Hospital, Detroit, Michigan
| | - Wooju Jeong
- Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan
| | - Patrick Hensley
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Neema Navai
- Department of Urology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - James O Peabody
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan; Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan
| | - Quoc-Dien Trinh
- Division of Urological Surgery and Center for Surgery and Public Health, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusettsa
| | - Craig G Rogers
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan; Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan
| | - Mani Menon
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan; Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan
| | - Firas Abdollah
- VCORE - Vattikuti Urology Institute Center for Outcomes Research, Analytics and Evaluation, Henry Ford Hospital, Detroit, Michigan; Vattikuti Urology Institute, Henry Ford Hospital, Detroit, Michigan
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8
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Peard L, Goodwin J, Hensley P, Dugan A, Bylund J, Harris AM. Examining and Understanding Value: The Impact of Preoperative Characteristics, Intraoperative Variables, and Postoperative Complications on Cost of Robot-Assisted Laparoscopic Radical Prostatectomy. J Endourol 2019; 33:541-548. [DOI: 10.1089/end.2019.0066] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Affiliation(s)
- Leslie Peard
- Department of Urology, University of Kentucky College of Medicine, Lexington, Kentucky
- University of Kentucky Medical Center, Lexington, Kentucky
| | - Jeffrey Goodwin
- Department of Urology, University of Kentucky College of Medicine, Lexington, Kentucky
- University of Kentucky Medical Center, Lexington, Kentucky
| | - Patrick Hensley
- Department of Urology, University of Kentucky College of Medicine, Lexington, Kentucky
- University of Kentucky Medical Center, Lexington, Kentucky
| | - Adam Dugan
- University of Kentucky Medical Center, Lexington, Kentucky
- Department of Biostatistics, University of Kentucky College of Public Health, Lexington, Kentucky
| | - Jason Bylund
- Department of Urology, University of Kentucky College of Medicine, Lexington, Kentucky
- University of Kentucky Medical Center, Lexington, Kentucky
| | - Andrew M. Harris
- Department of Urology, University of Kentucky College of Medicine, Lexington, Kentucky
- University of Kentucky Medical Center, Lexington, Kentucky
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9
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Hensley P, Purdom M, Kyprianou N, Wang C, James A. MP65-16 NOVEL BIOMARKER SIGNATURE FOR PREDICTING PATHOLOGIC RESPONSE OF UROTHELIAL CARCINOMA OF THE BLADDER TO CISPLATIN-BASED NEOADJUVANT CHEMOTHERAPY. J Urol 2018. [DOI: 10.1016/j.juro.2018.02.2082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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10
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Hensley P, Hilal T, Neltner J, Kumar B. Maintaining sharp focus on a grainy film: miliary pattern in an elderly woman with acute respiratory failure. BMJ Case Rep 2015. [PMID: 26202315 DOI: 10.1136/bcr-2015-210934] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
An elderly woman with a history of pulmonary tuberculosis reportedly diagnosed and treated 30 years prior to presentation was found unresponsive at home. Chest imaging revealed innumerable pulmonary nodules worrisome for an infectious process, specifically tuberculosis. The patient deteriorated rapidly and in accordance with her wishes, aggressive interventions were withheld. She died within 48 h from respiratory failure. A limited chest autopsy was performed and revealed the cause of death as lymphangitic spread of cancer from a primary lung adenocarcinoma.
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Affiliation(s)
- Patrick Hensley
- College of Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Talal Hilal
- Department of Internal Medicine, University of Kentucky, Lexington, Kentucky, USA
| | - Janna Neltner
- Department of Pathology, University of Kentucky, Lexington, Kentucky, USA
| | - Bharat Kumar
- Division of Immunology, University of Iowa, Iowa City, Iowa, USA
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11
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Abstract
The identification of the fundamental role of apoptosis in the growth balance and normal homeostasis against cell proliferation led to the recognition of its loss contributing to tumorigenesis. The mechanistic significance of reinstating apoptosis signaling towards selective targeting of malignant cells heavily exploits the caspase family of death-inducing molecules as a powerful therapeutic platform for the development of potent anticancer strategies. Some apoptosis inhibitors induce caspase expression and activity in preclinical models and clinical trials by targeting both the intrinsic and extrinsic apoptotic pathways and restoring the apoptotic capacity in human tumors. Furthermore, up-regulation of caspases emerges as a sensitizing mechanism for tumors exhibiting therapeutic resistance to radiation and adjuvant chemotherapy. This review provides a comprehensive discussion of the functional involvement of caspases in apoptosis control and the current understanding of reactivating caspase-mediated apoptosis signaling towards effective therapeutic modalities in cancer treatment.
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Affiliation(s)
- Patrick Hensley
- Department of Urology, University of Kentucky College of Medicine, 800 Rose Street, Lexington, KY 40536, USA
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12
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Myszka DG, Abdiche YN, Arisaka F, Byron O, Eisenstein E, Hensley P, Thomson JA, Lombardo CR, Schwarz F, Stafford W, Doyle ML. The ABRF-MIRG'02 study: assembly state, thermodynamic, and kinetic analysis of an enzyme/inhibitor interaction. J Biomol Tech 2003; 14:247-69. [PMID: 14715884 PMCID: PMC2279960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Fully characterizing the interactions involving biomolecules requires information on the assembly state, affinity, kinetics, and thermodynamics associated with complex formation. The analytical technologies often used to measure biomolecular interactions include analytical ultracentrifugation (AUC), isothermal titration calorimetry (ITC), and surface plasmon resonance (SPR). In order to evaluate the capabilities of core facilities to implement these technologies, the Association of Biomolecular Resource Facilities (ABRF) Molecular Interactions Research Group (MIRG) developed a standardized model system and distributed it to a panel of AUC, ITC, and SPR operators. The model system was composed of a well-characterized enzyme-inhibitor pair, namely bovine carbonic anhydrase II (CA II) and 4-carboxybenzenesulfonamide (CBS). Study participants were asked to measure one or more of the following: (1) the molecular mass, homogeneity, and assembly state of CA II by AUC; (2) the affinity and thermodynamics for complex formation by ITC; and (3) the affinity and kinetics of complex formation by SPR. The results from this study provide a benchmark for comparing the capabilities of individual laboratories and for defining the utility of the different instrumentation.
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Affiliation(s)
- D G Myszka
- University of Utah, Salt Lake City, Utah 84132, USA.
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13
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Federici MM, Venkat K, Bam N, Patel K, Dal Monte PR, Fernie B, Hensley P, Carr S, Baldoni J, Truneh A, Erickson J. Detection and consequences of recombinant protein isoforms: implications for biological potency. Dev Biol (Basel) 2003; 113:53-7; discussion 113-4. [PMID: 14620852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Various types of structural variants have been observed in recombinant DNA - derived products. These isoforms include variations in post translational carbohydrate modifications where variations in site occupancy or unoccupied sites may occur. In addition, varying degrees of C-terminal processing and N-terminal substitutions have been observed. Isoforms may also be generated during processing and can include aggregated and/or chemically modified forms of the protein. Sophisticated analytical techniques exist for the identification and characterization of these structural variants. Several strategies have been used to isolate or enrich the isoform before molecular characterization. However, the effect these structural variations have on the biological activity of the product is less well understood. This may, in part, be due to the specificity and variability of the bioassay employed. This presentation describes the isolation and characterization of specific molecular isoforms for a monoclonal antibody product as well as an assessment of effects on biological activity.
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Affiliation(s)
- M M Federici
- GlaxoSmithKline Pharmaceuticals, King of Prussia, PA 10496-0939, USA.
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14
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15
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Hensley P, Doyle ML, Myszka DG, Woody RW, Brigham-Burke MR, Erickson-Miller CL, Griffin CA, Jones CS, McNulty DE, O'Brien SP, Amegadzie BY, MacKenzie L, Ryan MD, Young PR. Evaluating energetics of erythropoietin ligand binding to homodimerized receptor extracellular domains. Methods Enzymol 2001; 323:177-207. [PMID: 10944753 DOI: 10.1016/s0076-6879(00)23367-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Affiliation(s)
- P Hensley
- Pfizer Inc., Central Research Division, Groton, Connecticut 06340-9979, USA
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16
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Doyle ML, Brigham-Burke M, Blackburn MN, Brooks IS, Smith TM, Newman R, Reff M, Stafford WF, Sweet RW, Truneh A, Hensley P, O'Shannessy DJ. Measurement of protein interaction bioenergetics: application to structural variants of anti-sCD4 antibody. Methods Enzymol 2001; 323:207-30. [PMID: 10944754 DOI: 10.1016/s0076-6879(00)23368-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This chapter has described a bioenergetic analysis of the interaction of sCD4 with an IgG1 and two IgG4 derivatives of an anti-sCD4 MAb. The MAbs have identical VH and VL domains but differ markedly in their CH and CL domains, raising the question of whether their antigen-binding chemistries are altered. We find the sCD4-binding kinetics and thermodynamics of the MAbs are indistinguishable, which indicates rigorously that the molecular details of the binding interactions are the same. We also showed the importance of using multiple biophysical methods to define the binding model before the bioenergetics can be appropriately interpreted. Analysis of the binding thermodynamics and kinetics suggests conformational changes that might be coupled to sCD4 binding by these MAbs are small or absent.
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Affiliation(s)
- M L Doyle
- Department of Structural Biology, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406-0939, USA
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17
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Myszka DG, Sweet RW, Hensley P, Brigham-Burke M, Kwong PD, Hendrickson WA, Wyatt R, Sodroski J, Doyle ML. Energetics of the HIV gp120-CD4 binding reaction. Proc Natl Acad Sci U S A 2000; 97:9026-31. [PMID: 10922058 PMCID: PMC16815 DOI: 10.1073/pnas.97.16.9026] [Citation(s) in RCA: 336] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HIV infection is initiated by the selective interaction between the cellular receptor CD4 and gp120, the external envelope glycoprotein of the virus. We used analytical ultracentrifugation, titration calorimetry, and surface plasmon resonance biosensor analysis to characterize the assembly state, thermodynamics, and kinetics of the CD4-gp120 interaction. The binding thermodynamics were of unexpected magnitude; changes in enthalpy, entropy, and heat capacity greatly exceeded those described for typical protein-protein interactions. These unusual thermodynamic properties were observed with both intact gp120 and a deglycosylated and truncated form of gp120 protein that lacked hypervariable loops V1, V2, and V3 and segments of its N and C termini. Together with previous crystallographic studies, the large changes in heat capacity and entropy reveal that extensive structural rearrangements occur within the core of gp120 upon CD4 binding. CD spectral studies and slow kinetics of binding support this conclusion. These results indicate considerable conformational flexibility within gp120, which may relate to viral mechanisms for triggering infection and disguising conserved receptor-binding sites from the immune system.
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Affiliation(s)
- D G Myszka
- Department of Oncological Sciences, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA.
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18
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19
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Bridges KG, Hua Q, Brigham-Burke MR, Martin JD, Hensley P, Dahl CE, Digard P, Weiss MA, Coen DM. Secondary structure and structure-activity relationships of peptides corresponding to the subunit interface of herpes simplex virus DNA polymerase. J Biol Chem 2000; 275:472-8. [PMID: 10617641 DOI: 10.1074/jbc.275.1.472] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The interaction of the catalytic subunit of herpes simplex virus DNA polymerase with the processivity subunit, UL42, is essential for viral replication and is thus a potential target for antiviral drug discovery. We have previously reported that a peptide analogous to the C-terminal 36 residues of the catalytic subunit, which are necessary and sufficient for its interaction with UL42, forms a monomeric structure with partial alpha-helical character. This peptide and one analogous to the C-terminal 18 residues specifically inhibit UL42-dependent long chain DNA synthesis. Using multidimensional (1)H nuclear magnetic resonance spectroscopy, we have found that the 36-residue peptide contains partially ordered N- and C-terminal alpha-helices separated by a less ordered region. A series of "alanine scan" peptides derived from the C-terminal 18 residues of the catalytic subunit were tested for their ability to inhibit long-chain DNA synthesis and by circular dichroism for secondary structure. The results identify structural aspects and specific side chains that appear to be crucial for interacting with UL42. These findings may aid in the rational design of new drugs for the treatment of herpesvirus infections.
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Affiliation(s)
- K G Bridges
- Department of Biological Chemistry, Harvard Medical School, Boston, Massachusetts 02115, USA
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20
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Sossong TM, Brigham-Burke MR, Hensley P, Pearce KH. Self-activation of guanosine triphosphatase activity by oligomerization of the bacterial cell division protein FtsZ. Biochemistry 1999; 38:14843-50. [PMID: 10555966 DOI: 10.1021/bi990917e] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The essential bacterial cell division protein FtsZ (filamentation temperature-sensitive protein Z) is a distant homologue to the eukaryotic cytoskeletal protein tubulin. We have examined the GTP hydrolytic activity of Escherichia coli FtsZ using a real-time fluorescence assay that monitors phosphate production. The GTPase activity shows a dramatic, nonlinear dependence on FtsZ concentration, with activity only observed at enzyme concentrations greater than 1 microM. At 5 microM FtsZ, we have determined a K(m) of 82 microM GTP and a V(max) of 490 nmol of P(i) min(-1) (mg of protein)(-1). Hydrolysis of GTP requires Mg(2+) and other divalent cations substitute only poorly for this requirement. We have compared the concentration dependence of FtsZ GTPase activity with the oligomeric state by use of analytical ultracentrifugation and chemical cross-linking. Equilibrium analytical ultracentrifugation experiments show that FtsZ exists as 68% dimer and 13% trimer at 2 microM total protein concentration. Chemical cross-linking of FtsZ also shows that monomer, dimer, trimer, and tetramer species are present at higher (>2 microM) FtsZ concentrations. However, as shown by analytical centrifugation, GDP-bound FtsZ is significantly shifted to the monomeric state, which suggests that GTP hydrolysis regulates polymer destabilization. We also monitored the effect of nucleotide and metal ion on the secondary structure of FtsZ; nucleotide yielded no evidence of structural changes in FtsZ, but both Mg(2+) and Ca(2+) had significant effects on secondary structure. Taken together, our results support the hypothesis that Mg(2+)-dependent GTP hydrolysis by FtsZ requires oligomerization of FtsZ. On the basis of these results and structural comparisons with the alpha-beta tubulin dimer, GTP is likely hydrolyzed in a shared active site formed between two monomer subunits.
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Affiliation(s)
- T M Sossong
- Department of Anti-Infectives Research, SmithKline Beecham Pharmaceuticals, 1250 South Collegeville Road, Collegeville, Pennsylvania 19426, USA.
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21
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Harrop JA, McDonnell PC, Brigham-Burke M, Lyn SD, Minton J, Tan KB, Dede K, Spampanato J, Silverman C, Hensley P, DiPrinzio R, Emery JG, Deen K, Eichman C, Chabot-Fletcher M, Truneh A, Young PR. Herpesvirus entry mediator ligand (HVEM-L), a novel ligand for HVEM/TR2, stimulates proliferation of T cells and inhibits HT29 cell growth. J Biol Chem 1998; 273:27548-56. [PMID: 9765287 DOI: 10.1074/jbc.273.42.27548] [Citation(s) in RCA: 199] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Herpesvirus entry mediator (HVEM), a member of the tumor necrosis factor (TNF) receptor family, mediates herpesvirus entry into cells during infection. Upon overexpression, HVEM activates NF-kappaB and AP-1 through a TNF receptor-associated factor (TRAF)-mediated mechanism. Using an HVEM-Fc fusion protein, we screened soluble forms of novel TNF-related proteins derived from an expressed sequence tag data base. One of these, which we designated HVEM-L, specifically bound to HVEM-Fc with an affinity of 44 nM. This association was confirmed with soluble and membrane forms of both receptor and ligand. HVEM-L mRNA is expressed in spleen, lymph nodes, macrophages, and T cells and encodes a 240-amino acid protein. A soluble, secreted form of the protein stimulates proliferation of T lymphocytes during allogeneic responses, inhibits HT-29 cell growth, and weakly stimulates NF-kappaB-dependent transcription.
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Affiliation(s)
- J A Harrop
- Department of Molecular and Cellular Immunology, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA
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22
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Abstract
A general isothermal titration calorimetry method is described that can be used to determine equilibrium binding constants for high-affinity interactions of ligands with biological macromolecules. The method exploits the thermodynamic linkage between the ligand binding equilibrium constant and temperature. By measuring the binding enthalpy change for an interaction as a function of temperature directly, the change in affinity can be calculated with an integrated form of the van't Hoff equation that is applicable to ligand binding to biological macromolecules. When the temperature dependence of the affinity is combined with the absolute affinity determined independently at a convenient temperature (where the affinity can most accurately or most easily be measured), the absolute binding affinity over the entire temperature range is determined.
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Affiliation(s)
- M L Doyle
- Department of Structural Biology, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA
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23
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Shao X, Hensley P, Matthews CR. Construction and characterization of monomeric tryptophan repressor: a model for an early intermediate in the folding of a dimeric protein. Biochemistry 1997; 36:9941-9. [PMID: 9245428 DOI: 10.1021/bi9707786] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Tryptophan repressor (TR) from Escherichia coli is a homodimer whose highly helical subunits intertwine in a complex fashion. A monomeric version of Trp repressor has been constructed by introducing a pair of polar amino acids at the hydrophobic dimer interface. Analytical ultracentrifugation was used to show that the replacement of leucine at position 39 with glutamic acid results in a monomer/dimer equilibrium whose dissociation constant is 1.11 x 10(-)4 M at 25 degrees C and pH 7.6. Tryptophan fluorescence, both near- and far-UV circular dichroism, and NMR spectroscopies demonstrated that, at the micromolar concentrations where the monomer predominates, secondary and tertiary structure are present. Hydrophobic dye-binding experiments showed that nonpolar surface is accessible in the monomeric form. The urea-induced equilibrium unfolding of monomeric L39E TR was monitored by circular dichroism, fluorescence, and absorbance spectroscopies. Coincident transitions show that the urea denaturation process follows a simple two-state model involving monomeric native and unfolded forms. The free energy at standard state in the absence of denaturant was estimated to be 2.37 +/- 0.15 kcal mol-1, and the sensitivity of the unfolding transition to denaturant, the m value, was 0.86 +/- 0.04 kcal mol-1 M(urea)-1 at pH 7.6 and 25 degrees C. The thermal denaturation transition occurred over a broad temperature range, suggesting either that the enthalpy change is small or that intermediates may exist. Kinetic studies showed that both the refolding and unfolding of the monomer were complete in the mixing dead time of stopped-flow CD and fluorescence spectroscopy, 5 ms. These structural, thermodynamic, and kinetic results are very similar to those previously reported for an early, monomeric intermediate in the folding of the wild-type TR dimer [Mann, C. J., & Matthews, C. R. (1993) Biochemistry 32, 5282-5290]. The construction of a stable, monomeric form of TR that strongly resembles a transient folding intermediate should provide useful insights into the nature of the early events in the folding of TR.
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Affiliation(s)
- X Shao
- Department of Chemistry, Pennsylvania State University, University Park 16802, USA
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24
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Li J, Cook R, Doyle ML, Hensley P, McNulty DE, Chaiken I. Monomeric isomers of human interleukin 5 show that 1:1 receptor recruitment is sufficient for function. Proc Natl Acad Sci U S A 1997; 94:6694-9. [PMID: 9192627 PMCID: PMC21220 DOI: 10.1073/pnas.94.13.6694] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The normally dimeric human interleukin 5 (IL-5) was re-engineered into two monomeric isomer forms to investigate mechanistic features of receptor recognition. One form, denoted GM1-IL-5, is a CD-loop expanded form, in which an 8-residue linker designed for flexibility was inserted between residues 85 and 86. The second, denoted DABC-IL-5, is a circularly permuted form of human IL-5 in which a chain discontinuity was introduced in the CD loop and the two consequent chain fragments were joined at the normal N and C termini by a di-glycyl linker. Both IL-5 isomers folded into stable monomers in solution as shown by sedimentation equilibrium and CD and formed an intrachain disulfide bond predicted from the structure of wild type IL-5. From titration microcalorimetry and optical biosensor analyses, both monomers were shown to interact with the IL-5 receptor alpha chain with 1:1 stoichiometry and affinities 30- to 40-fold weaker than for the dimeric wild type protein. And both monomers stimulated cell proliferation of human IL-5 receptor positive cells with a concentration dependence close to that of wild type. The data show that both monomeric and dimeric forms of IL-5 function through similar 1:1 receptor alpha chain recruitment processes and that it is the helical packing of the monomeric four-helix bundle unit in IL-5, rather than the helical connectivity itself, that appears to play the major role in presenting structural epitopes to trigger functional receptor activation.
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Affiliation(s)
- J Li
- Department of Molecular Immunology, SmithKline Beecham Pharmaceuticals, 709 Swedeland Road, King of Prussia, PA 19406, USA
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25
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Li J, Cook R, Doyle M, Hensley P, McNulty D, Chaiken I. Functional receptor recruitment by monomeric forms of interleukin-5. Immunol Lett 1997. [DOI: 10.1016/s0165-2478(97)86141-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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26
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DeSilva TM, Harper SL, Kotula L, Hensley P, Curtis PJ, Otvos L, Speicher DW. Physical properties of a single-motif erythrocyte spectrin peptide: a highly stable independently folding unit. Biochemistry 1997; 36:3991-7. [PMID: 9092829 DOI: 10.1021/bi962412j] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Spectrin is a long flexible rod-like actin cross-linking protein mostly comprised of many tandem homologous 106-residue motifs. In this study, the conformational stability and physical properties of a single homologous motif peptide, alpha1, were evaluated and compared to intact spectrin monomers and alphabeta heterodimers. It is interesting that while spectrin dimers elongate by about 3-fold in low ionic strength buffers relative to their size in physiological buffers, the single-motif peptide does not show significant changes in secondary structure in 10 mM phosphate buffer compared with isotonic buffer. This single-motif peptide is monomeric in physiological buffer as demonstrated by equilibrium sedimentation studies, and its hydrodynamic radius determined by gel filtration and dynamic light scattering of about 2.2 nm is consistent with an elongated rod-like shape. Unfolding of the single-motif peptide in urea solutions was similar to unfolding of intact heterodimers. Differential scanning calorimetry analyses showed that this single motif undergoes a reversible two-state transition with a Tm of 53 degrees C and an enthalpy of 65 kcal/mol in physiological buffer. Thermal stability was unaffected by ionic strength changes, but was decreased below physiological pH. These data show that this 13 kDa spectrin motif is a monomeric, highly stable, triple-helical, independently folding protein building block with physical characteristics that define many of the structural properties of the 526 kDa spectrin heterodimer. In contrast, interactions between adjacent motifs are probably responsible for spectrin's molecular flexibility and elasticity.
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Affiliation(s)
- T M DeSilva
- The Wistar Institute, Philadelphia, Pennsylvania 19104, USA
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27
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Shapiro L, Doyle JP, Hensley P, Colman DR, Hendrickson WA. Crystal structure of the extracellular domain from P0, the major structural protein of peripheral nerve myelin. Neuron 1996; 17:435-49. [PMID: 8816707 DOI: 10.1016/s0896-6273(00)80176-2] [Citation(s) in RCA: 286] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
P0, the major protein of peripheral nerve myelin, mediates membrane adhesion in the spiral wraps of the myelin sheath. We have determined the crystal structure of the extracellular domain from P0 (P0ex) at 1.9 A resolution. P0ex is folded like a typical immunoglobulin variable-like domain; five residues at the C-terminus are disordered, suggesting a flexible linkage to the membrane. The requirements for crystallization of P0ex are similar to those for maintaining the native extracellular spacing of adjacent myelin lamellae; thus, given the self-adhesive character of P0ex, the crystal itself may reveal some of the natural interactions that occur between P0 molecules in myelin. The structure leads to the suggestion that P0 extracellular domains may emanate from the membrane surface as tetramers that link to tetramers on the opposing membrane surface, to result in the formation of networks of molecules. We report analytical ultracentrifugation data for P0ex that support this idea.
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Affiliation(s)
- L Shapiro
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA
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28
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Hensley P. Defining the structure and stability of macromolecular assemblies in solution: the re-emergence of analytical ultracentrifugation as a practical tool. Structure 1996; 4:367-73. [PMID: 8740359 DOI: 10.1016/s0969-2126(96)00042-1] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- P Hensley
- Department of Macromolecular Sciences, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 194106-0939, USA
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29
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Shen F, Triezenberg SJ, Hensley P, Porter D, Knutson JR. Transcriptional activation domain of the herpesvirus protein VP16 becomes conformationally constrained upon interaction with basal transcription factors. J Biol Chem 1996; 271:4827-37. [PMID: 8617752 DOI: 10.1074/jbc.271.9.4827] [Citation(s) in RCA: 74] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The transcriptional activation domain of the herpesvirus protein VP16 resides in the carboxyl-terminal 78 amino acids (residues 413-490). Fluorescence analyses of this domain indicated that critical amino acids are solvent-exposed in highly mobile segments. To examine interactions between VP16 and components of the basal transcriptional machinery, we incorporated (at position 442 or 473 of VP16) tryptophan analogs that can be selectively excited in complexes with other Trp-containing proteins. TATA-box binding protein (TBP) (but not transcription factor B (TFIIB)) caused concentration-dependent changes in the steady-state anisotropy of VP16, from which equilibrium binding constants were calculated. Quenching of the fluorescence from either position (442 or 473) was significantly affected by TBP, whereas TFIIB affected quenching only at position 473. 7-aza-Trp residues at either position showed a emission spectral shift in the presence of TBP (but not TFIIB), indicating a change to a more hydrophobic environment. In anisotropy decay experiments, TBP reduced the segmental motion at either position; in contrast, TFIIB induced a slight change only at position 473. Our results support models of TBP as a target protein for transcriptional activators and suggest that ordered structure in the VP16 activation domain is induced upon interaction with target proteins.
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Affiliation(s)
- F Shen
- Biochemistry Department, Michigan State University, East Lansing, Michigan 48824-1319, USA
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30
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Shen F, Triezenberg SJ, Hensley P, Porter D, Knutson JR. Critical amino acids in the transcriptional activation domain of the herpesvirus protein VP16 are solvent-exposed in highly mobile protein segments. An intrinsic fluorescence study. J Biol Chem 1996; 271:4819-26. [PMID: 8617751 DOI: 10.1074/jbc.271.9.4819] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Eukaryotic transcriptional regulatory proteins typically comprise both a DNA binding domain and a regulatory domain. Although the structures of many DNA binding domains have been elucidated, no detailed structures are yet available for transcriptional activation domains. The activation domain of the herpesvirus protein VP16 has been an important model in mutational and biochemical studies. Here, we characterize the VP16 activation domain using time-resolved and steady-state fluorescence. Unique intrinsic fluorescent probes were obtained by replacing phenylalanine residues with tryptophan at position 442 or 473 of the activation domain of VP16 (residues 413-490, or subdomains thereof), linked to the DNA binding domain of the yeast protein GAL4. Emission spectra and quenching properties of Trp at either position were characteristic of fully exposed Trp. Time-resolved anisotropy decay measurements suggested that both Trp residues were associated with substantial segmental motion. The Trp residues at either position showed nearly identical fluorescence properties in either the full-length activation domain or relevant subdomains, suggesting that the two subdomains are similarly unstructured and have little effect on each other. As this domain may directly interact with several target proteins, it is likely that a significant structural transition accompanies these interactions.
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Affiliation(s)
- F Shen
- Biochemistry Department, Michigan State University, East Lansing, Michigan 48824-1319, USA
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31
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Chan W, Helms LR, Brooks I, Lee G, Ngola S, McNulty D, Maleeff B, Hensley P, Wetzel R. Mutational effects on inclusion body formation in the periplasmic expression of the immunoglobulin VL domain REI. Fold Des 1996; 1:77-89. [PMID: 9079368 DOI: 10.1016/s1359-0278(96)00017-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Inclusion body (IB) formation in bacteria is an important example of protein misassembly, a phenomenon which also includes folding-dependent aggregation in vitro and amyloid deposition in human disease. Previous studies of mutational effects in other systems implicate the stability of a folding intermediate-rather than the native state-as playing a key role in IB formation. To contribute to an understanding of the comparative biophysics of VL misassembly in different biological settings, we have studied mutation-dependent periplasmic IB formation by the VL domain REI in Escherichia coli. RESULTS A series of mutants were produced in periplasmic IBs, where, in all cases, the signal peptide was removed. In addition, the intradomain disulfide was clearly formed before deposition into IBs. IB formation in these mutants does not correlate with monomer/dimer equilibrium constants, but does correlate with the thermodynamic stability of the native state. CONCLUSIONS The results implicate a late, equilibrium folding intermediate in IB formation, in contrast to the apparent involvement of transient folding intermediates in other IB systems described to date. As equilibrium unfolding intermediates have also been implicated in light chain amyloidosis and deposition diseases, IB formation may prove a useful model for these human diseases.
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Affiliation(s)
- W Chan
- Department of Macromolecular Sciences, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406, USA
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Dodd I, Mossakowska DE, Camilleri P, Haran M, Hensley P, Lawlor EJ, McBay DL, Pindar W, Smith RA. Overexpression in Escherichia coli, folding, purification, and characterization of the first three short consensus repeat modules of human complement receptor type 1. Protein Expr Purif 1995; 6:727-36. [PMID: 8746624 DOI: 10.1006/prep.1995.0003] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We have developed a simple expression, isolation, and folding protocol for an SCR oligomer comprising the first three SCRs of complement receptor Type 1 (C3b/C4b receptor, CD35). A T7 RNA polymerase expression system in Escherichia coli was used to express the oligomer as inclusion bodies. The oligomer was recovered from solubilized inclusion bodies using batch adsorption on SP-Sepharose. The oligomer was folded by one-step dilution in 20 mM ethanolamine/1 mM EDTA supplemented with 1 mM GSH/0.5 mM GSSG. The folded material was processed to a concentrated (> 20 mg/ml), usable product of greater than 98% purity using a combination of ultrafiltration, ammonium sulfate treatment, hydrophobic interaction, and size-exclusion chromatography. The yield of folded material varied between 6 and 15 mg/liter culture. The oxidation states of the 12 cysteine residues in SCR(1-3) were identified by HPLC of peptide fragments from a tryptic digest using dual UV/fluorescence detection, collection of selected peaks, and N-terminal sequencing. This methodology confirmed the expected location of disulfide bridges. Equilibrium and velocity sedimentation studies are interpreted in terms of a single sedimenting species with molecular weights of 21,629 and 21,063 by these respective techniques. These values compare to the predicted molecular weight, from amino acid composition, of 21,817. The hydrodynamic properties of the molecule indicate that it is asymmetric with an axial ratio of 1:5.2 or equivalent dimensions of 21 x 110 A. SCR(1-3) has an unusual CD spectrum exhibiting a broad maximum at 220-230 nm and a minimum at 190 nm. There was little evidence of classical secondary structure. The product exhibited concentration-dependent inhibition of complement-mediated lysis of sensitized sheep red blood cells.
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Affiliation(s)
- I Dodd
- Department of Protein Chemistry, SmithKline Beecham Pharmaceuticals, Epsom, Surrey, United Kingdom
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33
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Johanson K, Appelbaum E, Doyle M, Hensley P, Zhao B, Abdel-Meguid SS, Young P, Cook R, Carr S, Matico R. Binding interactions of human interleukin 5 with its receptor alpha subunit. Large scale production, structural, and functional studies of Drosophila-expressed recombinant proteins. J Biol Chem 1995; 270:9459-71. [PMID: 7721873 DOI: 10.1074/jbc.270.16.9459] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Human interleukin 5 (hIL5) and soluble forms of its receptor alpha subunit were expressed in Drosophila cells and purified to homogeneity, allowing a detailed structural and functional analysis. B cell proliferation confirmed that the hIL5 was biologically active. Deglycosylated hIL5 remained active, while similarly deglycosylated receptor alpha subunit lost activity. The crystal structure of the deglycosylated hIL5 was determined to 2.6-A resolution and found to be similar to that of the protein produced in Escherichia coli. Human IL5 was shown by analytical ultracentrifugation to form a 1:1 complex with the soluble domain of the hIL5 receptor alpha subunit (shIL5R alpha). Additionally, the relative abundance of ligand and receptor in the hIL5.shIL5R alpha complex was determined to be 1:1 by both titration calorimetry and SDS-polyacrylamide gel electrophoresis analysis of dissolved cocrystals of the complex. Titration microcalorimetry yielded equilibrium dissociation constants of 3.1 and 2.0 nM, respectively, for the binding of hIL5 to shIL5R alpha and to a chimeric form of the receptor containing shIL5R alpha fused to the immunoglobulin Fc domain (shIL5R alpha-Fc). Analysis of the binding thermodynamics of IL5 and its soluble receptor indicates that conformational changes are coupled to the binding reaction. Kinetic analysis using surface plasmon resonance yielded data consistent with the Kd values from calorimetry and also with the possibility of conformational isomerization in the interaction of hIL5 with the receptor alpha subunit. Using a radioligand binding assay, the affinity of hIL5 with full-length hIL5R alpha in Drosophila membranes was found to be 6 nM, in accord with the affinities measured for the soluble receptor forms. Hence, most of the binding energy of the alpha receptor is supplied by the soluble domain. Taken with other aspects of hIL5 structure and biological activity, the data obtained allow a prediction for how 1:1 stoichiometry and conformational change can lead to the formation of hIL5.receptor alpha beta complex and signal transduction.
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Affiliation(s)
- K Johanson
- Department of Protein Biochemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA
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Digard P, Williams KP, Hensley P, Brooks IS, Dahl CE, Coen DM. Specific inhibition of herpes simplex virus DNA polymerase by helical peptides corresponding to the subunit interface. Proc Natl Acad Sci U S A 1995; 92:1456-60. [PMID: 7878000 PMCID: PMC42538 DOI: 10.1073/pnas.92.5.1456] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The herpes simplex virus DNA polymerase consists of two subunits--a catalytic subunit and an accessory subunit, UL42, that increases processivity. Mutations affecting the extreme C terminus of the catalytic subunit specifically disrupt subunit interactions and ablate virus replication, suggesting that new antiviral drugs could be rationally designed to interfere with polymerase heterodimerization. To aid design, we performed circular dichroism (CD) spectroscopy and analytical ultracentrifugation studies, which revealed that a 36-residue peptide corresponding to the C terminus of the catalytic subunit folds into a monomeric structure with partial alpha-helical character. CD studies of shorter peptides were consistent with a model where two separate regions of alpha-helix interact to form a hairpin-like structure. The 36-residue peptide and a shorter peptide corresponding to the C-terminal 18 residues blocked UL42-dependent long-chain DNA synthesis at concentrations that had no effect on synthesis by the catalytic subunit alone or by calf thymus DNA polymerase delta and its processivity factor. These peptides, therefore, represent a class of specific inhibitors of herpes simplex virus DNA polymerase that act by blocking accessory-subunit-dependent synthesis. These peptides or their structures may form the basis for the synthesis of clinically effective drugs.
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Affiliation(s)
- P Digard
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115
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35
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Hensley P, McDevitt PJ, Brooks I, Trill JJ, Feild JA, McNulty DE, Connor JR, Griswold DE, Kumar NV, Kopple KD. The soluble form of E-selectin is an asymmetric monomer. Expression, purification, and characterization of the recombinant protein. J Biol Chem 1994; 269:23949-58. [PMID: 7523364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The gene coding for a soluble form of human E-selectin (sE-selectin) has been expressed in Chinese hamster ovary (CHO) cells. Cells seeded into a hollow fiber reactor secreted protein at a level of 160 mg/liter. The protein was purified to > 95% pure and low endotoxin (< 2 ng/mg), using physiological pH and buffers. The amino acid composition and N-terminal sequence were as predicted from the cDNA sequence. HL-60 cells bound to sE-selectin-coated plates in a dose-dependent manner, and this binding could be blocked up to 100% by pretreatment of HL60 cells with sE-selectin. The concentration of sE-selectin required for 50% inhibition was 1 microM. This value puts an upper limit for the affinity of E-selectin for its natural receptor. sE-selectin also inhibited inflammatory migration of neutrophils in a selective fashion. Purified sE-selectin exhibited a broad band of M(r) approximately 75,000 on nonreducing SDS-PAGE. sE-selectin eluted with M(r) approximately 310,000 from size exclusion chromatography at physiological pH and buffers, suggesting an oligomeric state. Matrix-assisted laser-desorption MS gave a molecular weight of 80,000, while the minimum monomer molecular weight from the gene sequence should be 58,571, demonstrating that the monomeric molecule thus expressed had 27% carbohydrate. Equilibrium analytical ultracentrifugation gave an average solution molecular weight of 81,600 (+/- 4,500). Velocity ultracentrifugation gave a sedimentation coefficient of 4.3 S and, from this, an apparent axial ratio of 10.5:1, assuming a prolate ellipsoid of revolution. An analysis of the NMR NOESY spectra of sE-selectin, sialyl-Lewis X, and sE-selectin with sialyl-Lewis X demonstrates that the recombinant protein binds sialyl-Lewis X productively. Hence, in solution, sE-selectin is a functional elongated monomer.
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Affiliation(s)
- P Hensley
- Department of Macromolecular Sciences, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406-0939
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36
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Hensley P, McDevitt P, Brooks I, Trill J, Feild J, McNulty D, Connor J, Griswold D, Kumar N, Kopple K. The soluble form of E-selectin is an asymmetric monomer. Expression, purification, and characterization of the recombinant protein. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)51030-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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37
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Hsieh M, Hensley P, Brenowitz M, Fetrow JS. A molecular model of the inducer binding domain of the galactose repressor of Escherichia coli. J Biol Chem 1994; 269:13825-35. [PMID: 8188660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
The C-terminal inducer binding domain of the Escherichia coli galactose repressor (GalR) is homologous to several periplasmic chemoreceptor proteins whose three-dimensional structures have been determined at high resolution (Vyas, N. K., Vyas, M. N., and Quiocho, F. A. (1991) J. Biol. Chem. 266, 5226-5237; Mowbray, S. L. and Cole, L. B. (1992) J. Mol. Biol. 225, 155-175). The protein backbone was constructed from the coordinates of glucose/galactose-binding protein using the Homology program (Biosym Technologies, San Diego). Loops were built by searching for substructures in the structure data base, and the side chains were built using a rotamer-base program. A small amount of energy minimization relieved steric strain within the model. The GalR model that has been constructed is consistent with the principles of protein structure; values obtained for the compactness and buried surface area of the model compare favorably with those determined for the chemoreceptor protein structures. The model is consistent with, and provides structural interpretations for, experimental results obtained from physical and biochemical studies. Predictions are made concerning the residues conferring the specificity of galactose induction of GalR and for self-association to dimers. The model provides a first step toward correlating the structure and regulation of GalR and in determining the chemistry of its homologous and heterologous interactions that are critical to its role as a regulator of transcription initiation.
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Affiliation(s)
- M Hsieh
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, New York 10461
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38
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Hsieh M, Hensley P, Brenowitz M, Fetrow J. A molecular model of the inducer binding domain of the galactose repressor of Escherichia coli. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)36722-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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39
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Gowda DC, Jackson CM, Hensley P, Davidson EA. Factor X-activating glycoprotein of Russell's viper venom. Polypeptide composition and characterization of the carbohydrate moieties. J Biol Chem 1994; 269:10644-50. [PMID: 8144654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
There is contradictory information regarding the molecular weight and polypeptide chain composition of RVV-X, a glycoprotein in Russell's viper venom that is capable of activating factor X to Xa. We show that RVV-X is a 92,880-Da glycoprotein. It consists of three disulfide-linked polypeptide chains, one heavy chain (alpha-chain, M(r) 57,600) and two light chains (beta- and gamma-chains, M(r) 19,400 and 16,400, respectively). The two light chains seen on SDS-polyacrylamide gel electrophoresis under reducing conditions are two distinct components of the molecule, rather than a heterogeneous mixture of a single chain as previously reported (Takeya, H., Nishida, S., Miyata, T., Kawada, S., Saisaka, Y., Morita, T., and Iwanaga, S. (1992) J. Biol. Chem. 267, 14109-14117). The following evidence supports this conclusion. (i) The two light chains of RVV-X are present in equal proportion. (ii) The estimated molecular weight of an alpha 1 beta 1 gamma 1-structure closely matches the molecular weight determined by matrix-assisted laser desorption mass spectrometry. (iii) The amino acid compositions and NH2-terminal sequences of the beta- and gamma-chains are different. (iv) Although both the beta- and gamma-chains contain one N-linked oligosaccharide chain each, they are glycosylated differentially. RVV-X contains six N-linked oligosaccharides, four in the alpha-chain and one in each of the beta- and gamma-chains. The carbohydrate structures are different from those known for other snake venom glycoproteins, and they resemble closely those in various mammalian glycoproteins. The majority of the oligosaccharides are complex bi-, tri-, and tetraantennary structures, with a small proportion of multiantennary and high mannose-type structures. Two notable structural features of RVV-X oligosaccharides are as follows. (i) Sialic acid residues are linked to beta-galactosyl residues solely by alpha 2,3-linkages, and (ii) bisecting N-acetylglucosamine residues are present in the majority of the oligosaccharides.
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Affiliation(s)
- D C Gowda
- Department of Biochemistry and Molecular Biology, Georgetown University Medical Center, Washington, D.C. 20007
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40
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Gowda D, Jackson C, Hensley P, Davidson E. Factor X-activating glycoprotein of Russell's viper venom. Polypeptide composition and characterization of the carbohydrate moieties. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)34108-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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41
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Abstract
The solution structure of the isolated VL domain of the anti-digoxin antibody 26-10 has been determined using data derived from heteronuclear multi-dimensional nuclear magnetic resonance (n.m.r.) experiments. Analytical ultracentrifugation and n.m.r. data demonstrate that the VL domain is only weakly associating (Kd = 2.5 (+/- 0.7) mM) and that it experiences a rapid monomer/dimer equilibrium under the n.m.r. experimental conditions. Therefore, the results reported here represent the first structure determination of an antibody VL domain in the absence of fixed quaternary interactions. The structure determination is based on 930 proton-proton distance constraints, 113 dihedral angle constraints, and 46 hydrogen bond constraints. Eighty initial structures were calculated with the variable target function program DIANA; of these, 31 were accepted on the basis of satisfaction of constraints (no distance constraint violations > 0.5 A; target function < 3.0 A2). Accepted DIANA structures were refined by restrained energy minimization using the X-PLOR program. The 15 best energy-minimized DIANA structures were chosen as a representative ensemble of solution conformations. The average root-mean-square differences (r.m.s.d.) between the individual structures of this ensemble and the mean coordinates is 0.85 (+/- 0.10) A for all backbone atoms and 1.29 (+/- 0.10) A for all heavy atoms. For beta-strands A, B, C, D, E and F, the average backbone atom r.m.s.d. to the mean structure is 0.46 (+/- 0.06) A. A higher-resolution ensemble, with all backbone atom and all heavy atom r.m.s.d.s. to the mean coordinates of 0.54 (+/- 0.08) A and 0.98 (+/- 0.12) A, respectively, was obtained by X-PLOR simulated annealing refinement of the 15 energy-minimized DIANA structures. A detailed analysis of the original ensemble of 15 energy-minimized DIANA structures is presented, as this ensemble retains a broader, and possibly more realistic, sampling of conformation space. The backbone atom and all heavy atom r.m.s.d.s between the mean energy-minimized DIANA structure and the X-ray derived coordinates of the VL domain within the Fab/digoxin complex are 1.05 A and 1.56 A, respectively. Subtle differences between the solution and X-ray structures occur primarily in CDR2, CDR3, beta-strands A, F and G, and localized regions of hydrophobic packing. Overall, these results demonstrate that the 26-10 VL domain conformation is determined primarily by intradomain interactions, and that quaternary VL-VH association induces relatively minor conformational adjustments.
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Affiliation(s)
- K L Constantine
- Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, NJ 08543
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42
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O'Shannessy DJ, Brigham-Burke M, Soneson KK, Hensley P, Brooks I. Determination of rate and equilibrium binding constants for macromolecular interactions by surface plasmon resonance. Methods Enzymol 1994; 240:323-49. [PMID: 7823837 DOI: 10.1016/s0076-6879(94)40054-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- D J O'Shannessy
- Department of Protein Biochemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406
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Brooks I, Watts DG, Soneson KK, Hensley P. Determining confidence intervals for parameters derived from analysis of equilibrium analytical ultracentrifugation data. Methods Enzymol 1994; 240:459-78. [PMID: 7823844 DOI: 10.1016/s0076-6879(94)40060-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
In the above discussion, we have introduced the profiling approach of Bates and Watts. It is an easy to implement, empirical approach to the determination of confidence intervals for parameters in nonlinear models. We have applied the approach to the analysis of equilibrium sedimentation data and have demonstrated that, although models for analyzing such data are formally nonlinear they are functionally linear. As such, linear approximation confidence intervals for the parameters are adequate for these models and data sets. Further, we have been able to examine the effect of implementing a multiple independent variable approach (in this case, using multiple rotor speeds) on the precision of the analysis. We found that the standard errors of the parameters were reduced and that this is accounted for by either the increase in the number of data points or the decreases in parameter correlation. In this case, profiling helped to visualize the effect on the sum of squares surface of reducing parameter correlation, making the effect of the small decreases in the correlation of some parameters more evident. Using profiling, it should be easy to explore other methods for the improvement of the analysis of ultracentrifugation data and to be able to quantitate the improvement. With the above discussion as an example, it is likely that the profiling approach should be quite useful and broadly applicable in the analysis of data in terms of nonlinear models.
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Affiliation(s)
- I Brooks
- Department of Macromolecular Sciences, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406
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O'Shannessy DJ, Brigham-Burke M, Soneson KK, Hensley P, Brooks I. Determination of rate and equilibrium binding constants for macromolecular interactions using surface plasmon resonance: use of nonlinear least squares analysis methods. Anal Biochem 1993; 212:457-68. [PMID: 8214588 DOI: 10.1006/abio.1993.1355] [Citation(s) in RCA: 399] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Surface plasmon resonance (SPR) is a label-free, real time, optical detection method which has recently been commercialized as the BIAcore (Pharmacia). The technique relies on the immobilization of one of the interactants, the ligand, onto a dextran-coated gold surface. The second interactant, the ligate, is then injected across the surface and the interaction of the soluble ligate with the immobilized ligand is observed continuously and directly. The process of dissociation of bound ligate may also be observed directly after the sample plug has traversed the layer. Thus, the data generated contain information on the kinetic rate and equilibrium binding constants for the interaction under investigation. Historically, data from this instrument have been analyzed in terms of linear transformations of the primary data and requires that data from several ligate concentrations be analyzed to determine a single value for the association and dissociation rate constants. Here we discuss the analysis of untransformed BIAcore data by nonlinear least squares methods. The primary data are analyzed according to the integrated rate equations which describe the kinetics of the interaction of soluble ligate with immobilized ligand and the dissociation of the formed complex from the surface, respectively. Such analyses allow the direct determination of the association and dissociation rate constants for each binding experiment and, further, allow the analysis of data over a wider concentration range with lower associated errors compared to previously described methods. Through the use of modeling these interactions, we also demonstrate the limitations in determining the dissociation rate constant from the association phase of the interaction, thereby requiring that the dissociation process be analyzed. Indeed, the dissociation phase should be analyzed first to yield a relatively precise and unambiguous value of the dissociation rate constant, kd, which can then be used to constrain the analysis of the association phase to yield a better estimate of the association rate constant, k(a). We further demonstrate that, at least for the interaction investigated, the apparent rate and equilibrium binding constants determined using SPR are concentration independent and can be determined with good reproducibility.
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Affiliation(s)
- D J O'Shannessy
- Department of Protein Biochemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406
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45
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Grant SK, Deckman IC, Culp JS, Minnich MD, Brooks IS, Hensley P, Debouck C, Meek TD. Use of protein unfolding studies to determine the conformational and dimeric stabilities of HIV-1 and SIV proteases. Biochemistry 1992; 31:9491-501. [PMID: 1390732 DOI: 10.1021/bi00154a023] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The free energies of dimer dissociation of the retroviral proteases (PRs) of human immunodeficiency virus type 1 (HIV-1) and simian immunodeficiency virus (SIV) were determined by measuring the effects of denaturants on the protein fluorescence upon the unfolding of the enzymes. HIV-1 PR was more stable to denaturation by chaotropes and extremes of pH and temperature than SIV PR, indicating that the former enzyme has greater conformational stability. The urea unfolding curves of both proteases were sigmoidal and single phase. The midpoints of the transition curves increased with increasing protein concentrations. These data were best described by and fitted to a two-state model in which folded dimers were in equilibrium with unfolded monomers. This denaturation model conforms to cases in which protein unfolding and dimer dissociation are concomitant processes in which folded monomers do not exist [Bowie, J. U., & Sauer, R. T. (1989) Biochemistry 28, 7140-7143]. Accordingly, the free energies of unfolding reflect the stabilities of the protease dimers, which for HIV-1 PR and SIV PR were, respectively, delta GuH2O = 14 +/- 1 kcal/mol (Ku = 39 pM) and 13 +/- 1 kcal/mol (Ku = 180 pM). The binding of a tight-binding, competitive inhibitor greatly stabilized HIV-1 PR toward urea-induced unfolding (delta GuH2O = 19.3 +/- 0.7 kcal/mol, Ku = 7.0 fM). There were also profound effects caused by adverse pH on the protein conformation for both HIV-1 PR and SIV PR, resulting in unfolding at pH values above and below the respective optimal ranges of 4.0-8.0 and 4.0-7.0
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Affiliation(s)
- S K Grant
- Department of Medicinal Chemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406-0939
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Rosé S, Hensley P, O'Shannessy DJ, Culp J, Debouck C, Chaiken I. Characterization of HIV-1 p24 self-association using analytical affinity chromatography. Proteins 1992; 13:112-9. [PMID: 1620693 DOI: 10.1002/prot.340130204] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Analytical affinity chromatography (AAC) was used to detect and quantitate the self-association of p24gag, the major structural capsid protein of human immunodeficiency virus (HIV-1). p24gag was immobilized on a hydrophilic polymer (methacrylate) chromatographic support. The resulting affinity column was able to interact with soluble p24, as judged by the chromatographic retardation of the soluble protein upon isocratic elution under nonchaotropic binding conditions. The variation of elution volume with soluble protein concentration fit to a monomer-dimer model for self-association. The soluble p24-immobilized p24 association process was observed using both frontal and zonal elution AAC at varying pH values; the dissociation constant was 3-4 x 10(-5) M at pH 7. That p24 monomer associates to dimers was determined in solution using analytical ultracentrifugation. The solution Kd was 1.3 x 10(-5) M at pH 7. AAC in the zonal elution mode provides a simple and rapid means to screen for other HIV-1 macromolecules that may interact with p24 as well as for modulators, including antagonists, of HIV p24 protein assembly.
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Affiliation(s)
- S Rosé
- Department of Macromolecular Sciences, Biopharmaceuticals R&D, SmithKline Beecham, King of Prussia, Pennsylvania 19406-0939
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47
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Affiliation(s)
- P Hensley
- Macromolecular Sciences Department, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406
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48
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Green SM, Ginsburg A, Lewis MS, Hensley P. Roles of metal ions in the maintenance of the tertiary and quaternary structure of arginase from Saccharomyces cerevisiae. J Biol Chem 1991; 266:21474-81. [PMID: 1939179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Arginase from Saccharomyces cerevisiae has long been known to be a metal ion-requiring enzyme as it requires heating at 45 degrees C in the presence of 10 mM Mn2+ for catalytic activation. Metals are also thought to play a structural role in the enzyme, but the identity of the structural metal and its precise structural role have not been defined. Analysis of the metal ions that bind to yeast arginase by atomic absorption spectroscopy reveals that there is a weakly associated Mn2+ that binds to the trimeric enzyme with a stoichiometry of 1.04 +/- 0.05 mol of Mn2+ bound per subunit and an apparent K'D value of 26 microM at pH 7.0 and 4 degrees C. A more tightly associated Zn2+ ion can only be removed by dialysis against chelating agents. In occasional preparations, this site contained some Mn2+; however, Zn2+ and Mn2+ together bind to high affinity sites with a stoichiometry of 1.14 +/- 0.25/mol of subunit. Both the loosely associated catalytic Mn2+ ion and the more tightly associated structural Zn2+ ion confer stability to the enzyme. Removal of the weakly bound Mn2+ ion results in a 3 degree C decrease in the midpoint of the thermal transition (T 1/2) (from 57 by 54 degrees C) as monitored by UV difference absorption spectroscopy. Removal of the tightly bound Zn2+ ion produces a 19 degrees C decrease in T 1/2 (to 38 degrees C). Similar results are obtained by circular dichroism measurements. When the Zn2+ ion is removed, the steady-state fluorescence intensity increases 100% as compared to the holoenzyme, with a shift in the emission maximum from 337 to 352 nm. This suggests that in the folded trimeric metalloenzyme, the tryptophan fluorescence is quenched and that upon removal of the structural metal, the quenching is relieved as tryptophan residues become exposed to more polar environments. Equilibrium sedimentation experiments performed after dialysis of the enzyme against EDTA demonstrate that arginase exists in a reversible monomer-trimer equilibrium, in the absence of metal ions, with a KD value of 5.05 x 10(-11) M2. In contrast, the native enzyme exists as a trimer with no evidence of dissociation when Mn2+ and Zn2+ are present (Eisenstein, E., Duong, L.T., Ornberg, R. L., Osborne, J.C., Jr., and Hensley, P. (1986) J. Biol. Chem. 261, 12814-12819). In summary, the study presented here demonstrates that binding of a weakly bound Mn2+ ion confers catalytic activity. In contrast, binding of a more tightly associated Zn2+ ion confers substantial stability to the tertiary and quaternary structure of the enzyme.
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Affiliation(s)
- S M Green
- Department of Biochemistry and Molecular Biology, Georgetwon University Medical Center, Washington, D.C. 20007
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Green SM, Knutson JR, Hensley P. Steady-state fluorescence and time-resolved fluorescence monitor changes in tryptophan environment in arginase from Saccharomyces cerevisiae upon removal of catalytic and structural metal ions. Biochemistry 1990; 29:9159-68. [PMID: 2271585 DOI: 10.1021/bi00491a009] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Yeast arginase is a trimeric protein of identical subunits, each containing three tryptophans. Time-resolved fluorescence and steady-state fluorescence were employed to monitor the effects of removing the weakly bound catalytic Mn2+ as well as the tightly bound structural Zn2+/Mn2+. Resolution of the total native emission spectrum into decay-associated spectra (DAS) yielded components with lifetimes of 0.1, 1.2, and 4.0 ns. Upon removal of the catalytic metal, the intensities increased approximately 20% while the lifetimes increased less than 10%, and the DAS were unchanged except in intensity. The two major components are well resolved, but the 0.1-ns term is small and dominated by scattered excitation. In contrast, removal of the structural metal increased decay times to 0.2, 1.8, and 5.3 ns. More important, both native DAS red-shifted and became indistinguishable. These data suggest that removal of the catalytic metal does little to change the microenvironments of the individual tryptophans while removal of the structural metal causes partial unfolding of the protein. The excitation spectra for the active and inactive trimers were resolved into their excitation DAS (IEDAS), suggesting ground-state heterogeneity of the fluorescent species. In contrast, the excitation spectra of arginase without the structural metal could not be resolved due to the indistinguishable DAS. The tryptophans are quenched by acrylamide but not by cesium or iodide. Global analysis of the acrylamide quenching data resulted in two quenching decay-associated spectra (QDAS) which correlated well with the DAS. Since the apoenzyme does not exhibit tryptophan accessibility to either positive or negative ionic quenchers, one must assume that the "unfolded" monomeric protein retains considerable tertiary structure.
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Affiliation(s)
- S M Green
- Department of Biochemistry and Molecular Biology, Georgetown University, Washington, D.C. 20007
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Nardone G, Wastney ME, Hensley P. DNA structural polymorphism modulates the kinetics of superhelical DNA cleavage by BamHI restriction endonuclease. J Biol Chem 1990; 265:15308-15. [PMID: 2203775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A compartmental model developed by Hensley (Hensley, P., Nardone, G., Chirikjian, J.G., and Wastney, M. E., (1990) J. Biol. Chem. 265, 15300-15307) for analysis of the time courses of the cleavage of superhelical DNA substrates by the restriction endonuclease, BamHI, has been used to quantify the effects of changes in temperature, ionic strength, superhelical density, and the DNA substrate on the binding and strand cleavage processes. Studies reported here indicate that changes in topology may be introduced into the DNA substrate solely as a result of the plasmid preparation process and in the absence of covalent bond cleavage and ligation. These changes in topology have qualitatively different effects on the kinetics than those promoted by changes in the superhelical density. The former are removed by briefly warming the DNA prior to assay, suggesting that they are only kinetically stable, while the latter changes are not affected by heating. Increasing the [NaCl] from 0.01 M to 0.1 M increases the overall rate of plasmid cleavage by increasing both the rates of cleavage and enzyme DNA association. To describe the decrease in the overall cleavage rate observed in 0.15 M NaCl, an ionic strength-dependent rate-determining structural transition in the DNA substrate was incorporated into the model. The largest changes in the rate of the cleavage process resulted from changes in the DNA substrate. For the SV40 substrate compared to pBR322, the rate constants describing the two association processes and the first bond cleavage event were increased 6- to 7-fold. The rate of the second bond cleavage process was not affected. These changes may be due to differences in the flanking sequences.
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Affiliation(s)
- G Nardone
- Department of Biochemistry, Georgetown University Medical Center, Washington, D.C. 20007
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