15 results on '"Gillis NK"'
Search Results
2. Identification of Clonal Hematopoiesis Mutations in Solid Tumor Patients Undergoing Unpaired Next-Generation Sequencing Assays.
- Author
-
Coombs CC, Gillis NK, Tan X, Berg JS, Ball M, Balasis ME, Montgomery ND, Bolton KL, Parker JS, Mesa TE, Yoder SJ, Hayward MC, Patel NM, Richards KL, Walko CM, Knepper TC, Soper JT, Weiss J, Grilley-Olson JE, Kim WY, Earp HS 3rd, Levine RL, Papaemmanuil E, Zehir A, Hayes DN, and Padron E
- Subjects
- Adult, Aged, Biomarkers, Computational Biology methods, Female, Genome-Wide Association Study, High-Throughput Nucleotide Sequencing, Humans, Male, Middle Aged, Neoplasms diagnosis, Clonal Evolution genetics, Hematopoiesis genetics, Mutation, Neoplasms genetics
- Abstract
Purpose: In this era of precision-based medicine, for optimal patient care, results reported from commercial next-generation sequencing (NGS) assays should adequately reflect the burden of somatic mutations in the tumor being sequenced. Here, we sought to determine the prevalence of clonal hematopoiesis leading to possible misattribution of tumor mutation calls on unpaired Foundation Medicine NGS assays., Experimental Design: This was a retrospective cohort study of individuals undergoing NGS of solid tumors from two large cancer centers. We identified and quantified mutations in genes known to be frequently altered in clonal hematopoiesis ( DNMT3A, TET2, ASXL1, TP53, ATM, CHEK2, SF3B1, CBL, JAK2 ) that were returned to physicians on clinical Foundation Medicine reports. For a subset of patients, we explored the frequency of true clonal hematopoiesis by comparing mutations on Foundation Medicine reports with matched blood sequencing., Results: Mutations in genes that are frequently altered in clonal hematopoiesis were identified in 65% (1,139/1,757) of patients undergoing NGS. When excluding TP53 , which is often mutated in solid tumors, these events were still seen in 35% (619/1,757) of patients. Utilizing paired blood specimens, we were able to confirm that 8% (18/226) of mutations reported in these genes were true clonal hematopoiesis events. The majority of DNMT3A mutations (64%, 7/11) and minority of TP53 mutations (4%, 2/50) were clonal hematopoiesis., Conclusions: Clonal hematopoiesis mutations are commonly reported on unpaired NGS testing. It is important to recognize clonal hematopoiesis as a possible cause of misattribution of mutation origin when applying NGS findings to a patient's care. See related commentary by Pollyea, p. 5790 ., (©2018 American Association for Cancer Research.)
- Published
- 2018
- Full Text
- View/download PDF
3. Somatic Sequencing Identifies Trametinib-Responsive Myelodysplastic Syndrome and Finds Acquired Clonal Hematopoiesis of Indeterminate Potential.
- Author
-
Vela CM, Van den Bergh M, Gillis NK, Ball M, Hussaini MO, Walko CM, Hicks JK, Perez L, Padron E, and Komrokji RS
- Abstract
Competing Interests: The following represents disclosure information provided by authors of this manuscript. All relationships are considered compensated. Relationships are self-held unless noted. I = Immediate Family Member, Inst = My Institution. Relationships may not relate to the subject matter of this manuscript. For more information about ASCO's conflict of interest policy, please refer to www.asco.org/rwc or ascopubs.org/po/author-center. Cory M. VelaNo relationship to discloseMagali Van den BerghNo relationship to discloseNancy K. GillisNo relationship to discloseMarkus BallNo relationship to discloseMohammad O. HussainiNo relationship to discloseChristine M. WalkoHonoraria: Merck, Bristol-Myers SquibbJ. Kevin HicksNo relationship to discloseLia PerezNo relationship to discloseEric PadronHonoraria: Incyte, Cell Therapeutics, Cell Therapeutics (Inst) Research Funding: Incyte (Inst)Rami S. KomrokjiStock and Other Ownership Interests: Abbvie Consulting or Advisory Role: Celgene, Novartis Speakers' Bureau: Novartis, Alexion Pharmaceuticals Research Funding: Incyte (Inst), Celgene (Inst), GlaxoSmithKline (Inst), Eleos (Inst), Boehringer Ingelheim (Inst) Travel, Accommodations, Expenses: Celgene, Incyte, Alexion Pharmaceuticals, Novartis
- Published
- 2018
- Full Text
- View/download PDF
4. Tumor exome sequencing and copy number alterations reveal potential predictors of intrinsic resistance to multi-targeted tyrosine kinase inhibitors.
- Author
-
Gillis NK, Rotroff DM, Mesa TE, Yao J, Chen Z, Carulli MA, Yoder SJ, Walko CM, Teer JK, and McLeod HL
- Abstract
Multi-targeted tyrosine kinase inhibitors (TKIs) have broad efficacy and similar FDA-approved indications, suggesting shared molecular drug targets across cancer types. Irrespective of tumor type, 20-30% of patients treated with multi-targeted TKIs demonstrate intrinsic resistance, with progressive disease as a best response. We conducted a retrospective cohort study to identify tumor (somatic) point mutations, insertion/deletions, and copy number alterations (CNA) associated with intrinsic resistance to multi-targeted TKIs. Using a candidate gene approach (n=243), tumor next-generation sequencing and CNA data was associated with resistant and non-resistant outcomes. Resistant individuals (n=11) more commonly harbored somatic point mutations in NTRK1 , KDR , TGFBR2 , and PTPN11 and CNA in CDK4 , CDKN2B , and ERBB2 compared to non-resistant (n=26, p<0.01). Using a random forest classification model for variable reduction and a decision tree classification model, we were able to differentiate intrinsically resistant from non-resistant patients. CNA in CDK4 and CDKN2B were the most important analytical features, implicating the cyclin D pathway as a potentially important factor in resistance to multi-targeted TKIs. Replication of these results in a larger, independent patient cohort has potential to inform personalized prescribing of these widely utilized agents., Competing Interests: CONFLICTS OF INTEREST The authors declared no conflicts of interest.
- Published
- 2017
- Full Text
- View/download PDF
5. Chipping in on clonal hematopoiesis.
- Author
-
Gillis NK and Padron E
- Published
- 2017
- Full Text
- View/download PDF
6. Quantitation of Targetable Somatic Mutations Among Patients Evaluated by a Personalized Medicine Clinical Service: Considerations for Off-Label Drug Use.
- Author
-
Vela CM, Knepper TC, Gillis NK, Walko CM, McLeod HL, and Hicks JK
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Drug Labeling methods, Female, High-Throughput Nucleotide Sequencing methods, Humans, Male, Middle Aged, Molecular Targeted Therapy methods, Neoplasms epidemiology, United States epidemiology, United States Food and Drug Administration, Young Adult, Antineoplastic Agents therapeutic use, Mutation genetics, Neoplasms drug therapy, Neoplasms genetics, Off-Label Use, Precision Medicine methods
- Abstract
Introduction: Moffitt Cancer Center's Personalized Medicine Clinical Service (PMCS) reviews somatic next-generation sequencing (NGS) assay results, provides interpretations, and identifies potential therapeutic options. The number of individuals reviewed by our clinical service who are eligible for on-label or off-label drug therapy based on genetic test results has previously not been quantitated. We determined the number of patients harboring an actionable mutation that would qualify a patient for an on-label drug or consideration for off-label drug treatment., Methods: The Food and Drug Administration (FDA) Table of Pharmacogenomic Biomarkers in Drug Labeling was utilized to identify anticancer agents containing genomic markers in the Indications and Usage section of the drug label. A database containing discrete NGS patient data was queried retrospectively for those drugs and associated genomic mutations included in this study. On-label was defined as those patients who were eligible for a drug based on harboring a targetable mutation in the FDA-approved cancer type. Off-label was defined as those patients who may be considered for a drug based on harboring a targetable mutation in a non-FDA-approved cancer type., Results: A total of 1072 patients and 1131 NGS results were eligible for study inclusion. Fifty-two patients (4.9%) had results for more than one NGS assay. Seventeen drugs targeting ALK, BRAF, BRCA1/BRCA2, EGFR, or ERBB2 mutations met the study inclusion criteria. Of the entire patient population, 92 (8.6%) unique patients were eligible for at least one on-label drug; off-label use of at least one drug could be considered in 103 (9.6%) unique patients., Conclusion: Combining both on-label and off-label opportunities, 175 (16.3%) unique patients had actionable mutations in six genes. Because most patients reviewed by our PMCS have previously treated advanced disease with limited treatment options, identifying additional lines of therapy is of clinical utility., (© 2017 Pharmacotherapy Publications, Inc.)
- Published
- 2017
- Full Text
- View/download PDF
7. Incidence and Triggers of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in a Large Cancer Patient Cohort.
- Author
-
Gillis NK, Hicks JK, Bell GC, Daly AJ, Kanetsky PA, and McLeod HL
- Subjects
- Global Health, Humans, Incidence, Risk Factors, Stevens-Johnson Syndrome etiology, Neoplasms complications, Risk Assessment, Stevens-Johnson Syndrome epidemiology
- Published
- 2017
- Full Text
- View/download PDF
8. Key Lessons Learned from Moffitt's Molecular Tumor Board: The Clinical Genomics Action Committee Experience.
- Author
-
Knepper TC, Bell GC, Hicks JK, Padron E, Teer JK, Vo TT, Gillis NK, Mason NT, McLeod HL, and Walko CM
- Subjects
- Female, Humans, Male, Genomics, Molecular Targeted Therapy methods, Neoplasms therapy, Precision Medicine methods
- Abstract
Background: The increasing practicality of genomic sequencing technology has led to its incorporation into routine clinical practice. Successful identification and targeting of driver genomic alterations that provide proliferative and survival advantages to tumor cells have led to approval and ongoing development of several targeted cancer therapies. Within many major cancer centers, molecular tumor boards are constituted to shepherd precision medicine into clinical practice., Materials and Methods: In July 2014, the Clinical Genomics Action Committee (CGAC) was established as the molecular tumor board companion to the Personalized Medicine Clinical Service (PMCS) at Moffitt Cancer Center in Tampa, Florida. The processes and outcomes of the program were assessed in order to help others move into the practice of precision medicine., Results: Through the establishment and initial 1,400 patients of the PMCS and its associated molecular tumor board at a major cancer center, five practical lessons of broad applicability have been learned: transdisciplinary engagement, the use of the molecular report as an aid to clinical management, clinical actionability, getting therapeutic options to patients, and financial considerations. Value to patients includes access to cutting-edge practice merged with individualized preferences in treatment and care., Conclusions: Genomic-driven cancer medicine is increasingly becoming a part of routine clinical practice. For successful implementation of precision cancer medicine, strategically organized molecular tumor boards are critical to provide objective evidence-based translation of observed molecular alterations into patient-centered clinical action. Molecular tumor board implementation models along with clinical and economic outcomes will define future treatment standards. The Oncologist 2017;22:144-151 Implications for Practice: It is clear that the increasing practicality of genetic tumor sequencing technology has led to its incorporation as part of routine clinical practice. Subsequently, many cancer centers are seeking to develop a personalized medicine services and/or molecular tumor board to shepherd precision medicine into clinical practice. This article discusses the key lessons learned through the establishment and development of a molecular tumor board and personalized medicine clinical service. This article highlights practical issues and can serve as an important guide to other centers as they conceive and develop their own personalized medicine services and molecular tumor boards., (© AlphaMed Press 2017.)
- Published
- 2017
- Full Text
- View/download PDF
9. Clonal haemopoiesis and therapy-related myeloid malignancies in elderly patients: a proof-of-concept, case-control study.
- Author
-
Gillis NK, Ball M, Zhang Q, Ma Z, Zhao Y, Yoder SJ, Balasis ME, Mesa TE, Sallman DA, Lancet JE, Komrokji RS, List AF, McLeod HL, Alsina M, Baz R, Shain KH, Rollison DE, and Padron E
- Subjects
- Aged, Aged, 80 and over, Case-Control Studies, Clone Cells drug effects, Clone Cells metabolism, Female, Florida epidemiology, Follow-Up Studies, High-Throughput Nucleotide Sequencing methods, Humans, Incidence, Leukemia, Myeloid, Acute chemically induced, Leukemia, Myeloid, Acute epidemiology, Leukemia, Myeloid, Acute genetics, Male, Middle Aged, Mutation genetics, Myelodysplastic Syndromes chemically induced, Myelodysplastic Syndromes epidemiology, Myelodysplastic Syndromes genetics, Neoplasm Staging, Neoplasms pathology, Neoplasms, Second Primary chemically induced, Neoplasms, Second Primary epidemiology, Neoplasms, Second Primary genetics, Prognosis, Risk Factors, Survival Rate, Antineoplastic Combined Chemotherapy Protocols adverse effects, Biomarkers, Tumor genetics, Clone Cells pathology, Hematopoiesis genetics, Leukemia, Myeloid, Acute diagnosis, Myelodysplastic Syndromes diagnosis, Neoplasms drug therapy, Neoplasms, Second Primary diagnosis
- Abstract
Background: Clonal haemopoiesis of indeterminate potential (CHIP) is an age-associated genetic event linked to increased risk of primary haematological malignancies and increased all-cause mortality, but the prevalence of CHIP in patients who develop therapy-related myeloid neoplasms is unknown. We did this study to investigate whether chemotherapy-treated patients with cancer who have CHIP are at increased risk of developing therapy-related myeloid neoplasms., Methods: We did a nested, case-control, proof-of-concept study to compare the prevalence of CHIP between patients with cancer who later developed therapy-related myeloid neoplasms (cases) and patients who did not develop these neoplasms (controls). We identified cases from our internal biorepository of 123 357 patients who consented to participate in the Total Cancer Care biobanking protocol at Moffitt Cancer Center (Tampa, FL, USA) between Jan 1, 2006, and June 1, 2016. We included all individuals who were diagnosed with a primary malignancy, were treated with chemotherapy, subsequently developed a therapy-related myeloid neoplasm, and were 70 years or older at either diagnosis. For inclusion in this study, individuals must have had a peripheral blood or mononuclear cell sample collected before the diagnosis of therapy-related myeloid neoplasm. Controls were individuals who were diagnosed with a primary malignancy at age 70 years or older and were treated with chemotherapy but did not develop therapy-related myeloid neoplasms. Controls were matched to cases in at least a 4:1 ratio on the basis of sex, primary tumour type, age at diagnosis, smoking status, chemotherapy drug class, and duration of follow-up. We used sequential targeted and whole-exome sequencing and described clonal evolution in cases for whom paired CHIP and therapy-related myeloid neoplasm samples were available. The primary endpoint of this study was the development of therapy-related myeloid neoplasm and the primary exposure was CHIP., Findings: We identified 13 cases and 56 case-matched controls. The prevalence of CHIP in all patients (23 [33%] of 69 patients) was higher than has previously been reported in elderly individuals without cancer (about 10%). Cases had a significantly higher prevalence of CHIP than did matched controls (eight [62%] of 13 cases vs 15 [27%] of 56 controls, p=0·024; odds ratio 5·75, 95% CI 1·52-25·09, p=0·013). The most commonly mutated genes in cases with CHIP were TET2 (three [38%] of eight patients) and TP53(three [38%] of eight patients), whereas controls most often had TET2 mutations (six [40%] of 15 patients). In most (four [67%] of six patients) cases for whom paired CHIP and therapy-related myeloid neoplasm samples were available, the mean allele frequency of CHIP mutations had expanded by the time of the therapy-related myeloid neoplasm diagnosis. However, a subset of paired samples (two [33%] of six patients) had CHIP mutations that decreased in allele frequency, giving way to expansion of a distinct mutant clone., Interpretation: Patients with cancer who have CHIP are at increased risk of developing therapy-related myeloid neoplasms. The distribution of CHIP-related gene mutations differs between individuals with therapy-related myeloid neoplasm and those without, suggesting that mutation-specific differences might exist in therapy-related myeloid neoplasm risk., Funding: Moffitt Cancer Center., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
10. The pharmacogenomics of drug resistance to protein kinase inhibitors.
- Author
-
Gillis NK and McLeod HL
- Subjects
- Antineoplastic Agents administration & dosage, Antineoplastic Combined Chemotherapy Protocols administration & dosage, Cell Transformation, Neoplastic drug effects, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic metabolism, Cell Transformation, Neoplastic pathology, Clone Cells, Drug Chronotherapy, Drug Resistance, Neoplasm genetics, ErbB Receptors antagonists & inhibitors, ErbB Receptors genetics, ErbB Receptors metabolism, Humans, Molecular Targeted Therapy methods, Neoplasms enzymology, Neoplasms genetics, Neoplasms pathology, Protein Kinase Inhibitors administration & dosage, Protein Kinases genetics, Protein Kinases metabolism, Signal Transduction, Antineoplastic Agents pharmacokinetics, Antineoplastic Combined Chemotherapy Protocols pharmacokinetics, Drug Resistance, Neoplasm drug effects, Gene Expression Regulation, Neoplastic, Neoplasms drug therapy, Protein Kinase Inhibitors pharmacokinetics
- Abstract
Dysregulation of growth factor cell signaling is a major driver of most human cancers. This has led to development of numerous drugs targeting protein kinases, with demonstrated efficacy in the treatment of a wide spectrum of cancers. Despite their high initial response rates and survival benefits, the majority of patients eventually develop resistance to these targeted therapies. This review article discusses examples of established mechanisms of drug resistance to anticancer therapies, including drug target mutations or gene amplifications, emergence of alternate signaling pathways, and pharmacokinetic variation. This reveals a role for pharmacogenomic analysis to identify and monitor for resistance, with possible therapeutic strategies to combat chemoresistance., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
11. Evidence required to demonstrate clinical utility of pharmacogenetic testing: the debate continues.
- Author
-
Gillis NK and Innocenti F
- Subjects
- Biomarkers, Humans, Practice Guidelines as Topic, Genetic Testing, Pharmacogenetics
- Abstract
Pharmacogenetics is an area of research that has potential to greatly benefit patients. However, the routine use of diagnostic pharmacogenetic testing to inform treatment decisions is limited. Here we discuss the determination of clinical utility of pharmacogenetic testing and the level of evidence required to support translation into clinical practice.
- Published
- 2014
- Full Text
- View/download PDF
12. Acute coronary syndromes in older adults: a review of literature.
- Author
-
Gillis NK, Arslanian-Engoren C, and Struble LM
- Subjects
- Acute Coronary Syndrome diagnosis, Age Factors, Aged, Aged, 80 and over, Education, Medical, Continuing, Emergency Nursing methods, Emergency Treatment, Female, Geriatric Assessment methods, Humans, Male, Myocardial Infarction diagnosis, Prognosis, Risk Assessment, Sex Factors, Survival Analysis, Treatment Outcome, Vulnerable Populations, Acute Coronary Syndrome mortality, Acute Coronary Syndrome therapy, Emergency Service, Hospital statistics & numerical data, Hospital Mortality trends, Myocardial Infarction mortality, Myocardial Infarction therapy
- Abstract
Introduction: Acute coronary syndromes (ACS) are the leading cause of death in older adults, aged 65 years or older. The clinical presentation varies, and the absence of chest pain may occur. Our purpose was to synthesize the published literature (2000-2012) to (1) examine the initial ED presentation of older adults with confirmed ACS, (2) identify knowledge gaps, (3) determine whether gender differences exist in the presentation of ACS, and (4) describe recommendations for practice and research., Methods: A systematic review was conducted from September 2000 to September 2012., Results: The review suggests that older adults with ACS report chest pain more commonly when arriving to the emergency department. Older adults have higher in-hospital mortality rates than adults aged younger than 65 years. However, older adults reporting an absence of chest pain on arrival are twice as likely to die compared with older adults with chest pain. With regard to gender differences, we note that men are more likely to present with chest pain whereas women are more likely to present with nausea. Women have higher in-hospital mortality rates both with and without chest pain presentation. Delay in time to arrival, as well as delay to primary percutaneous intervention, is reported for older adults with and without chest pain., Discussion: Older adults with ACS are at risk for higher mortality rates and delays in time to treatment modalities. Early recognition of symptoms suggestive of ACS by the emergency triage nurse can improve patient outcomes., (Copyright © 2014 Emergency Nurses Association. Published by Mosby, Inc. All rights reserved.)
- Published
- 2014
- Full Text
- View/download PDF
13. Clinical implementation of germ line cancer pharmacogenetic variants during the next-generation sequencing era.
- Author
-
Gillis NK, Patel JN, and Innocenti F
- Subjects
- Biomarkers, Cost-Benefit Analysis, Evidence-Based Medicine, Government Agencies, Humans, Insurance, Health, High-Throughput Nucleotide Sequencing trends, Neoplasms, Germ Cell and Embryonal drug therapy, Neoplasms, Germ Cell and Embryonal genetics, Pharmacogenetics trends
- Abstract
More than 100 medications approved by the US Food and Drug Administration include pharmacogenetic biomarkers in the drug label, many with cancer indications referencing germ line DNA variations. With the advent of next-generation sequencing (NGS) and its rapidly increasing uptake into cancer research and clinical practice, an enormous amount of data to inform documented gene-drug associations will be collected that must be exploited to optimize patient benefit. This review focuses on the implementation of germ line cancer pharmacogenetics in clinical practice. Specifically, it discusses the importance of germ line variation in cancer and the role of NGS in pharmacogenetic discovery and implementation. In the context of a scenario in which massive amounts of NGS-based genetic information will be increasingly available to health stakeholders, this review explores the ongoing debate regarding the threshold of evidence necessary for implementation, provides an overview of recommendations in cancer by professional organizations and regulatory bodies, and discusses limitations of current guidelines and strategies to improve third-party coverage.
- Published
- 2014
- Full Text
- View/download PDF
14. Atenolol induced HDL-C change in the pharmacogenomic evaluation of antihypertensive responses (PEAR) study.
- Author
-
McDonough CW, Gillis NK, Alsultan A, Chang SW, Kawaguchi-Suzuki M, Lang JE, Shahin MH, Buford TW, El Rouby NM, Sá AC, Langaee TY, Gums JG, Chapman AB, Cooper-DeHoff RM, Turner ST, Gong Y, and Johnson JA
- Subjects
- ATP Binding Cassette Transporter, Subfamily B, ATP Binding Cassette Transporter, Subfamily B, Member 1 genetics, Adult, Black or African American genetics, Alpha-Ketoglutarate-Dependent Dioxygenase FTO, Antihypertensive Agents therapeutic use, Estrogen Receptor alpha genetics, Female, Genotype, Humans, Hypertension ethnology, Linear Models, Lipase genetics, Lipid Metabolism drug effects, Lipid Metabolism genetics, Low Density Lipoprotein Receptor-Related Protein-5 genetics, Male, Membrane Proteins genetics, Middle Aged, N-Acetylgalactosaminyltransferases genetics, Pharmacogenetics methods, Polymorphism, Single Nucleotide, Proteins genetics, White People genetics, Polypeptide N-acetylgalactosaminyltransferase, Atenolol therapeutic use, Cholesterol, HDL blood, Hypertension drug therapy, Hypertension genetics
- Abstract
We sought to identify novel pharmacogenomic markers for HDL-C response to atenolol in participants with mild to moderate hypertension. We genotyped 768 hypertensive participants from the Pharmacogenomic Evaluation of Antihypertensive Responses (PEAR) study on the Illumina HumanCVD Beadchip. During PEAR, participants were randomized to receive atenolol or hydrochlorothiazide. Blood pressure and cholesterol levels were evaluated at baseline and after treatment. This study focused on participants treated with atenolol monotherapy. Association with atenolol induced HDL-C change was evaluated in 232 whites and 152 African Americans using linear regression. No SNPs achieved a Bonferroni corrected P-value. However, we identified 13 regions with consistent association across whites and African Americans. The most interesting of these regions were seven with prior associations with HDL-C, other metabolic traits, or functional implications in the lipid pathway: GALNT2, FTO, ABCB1, LRP5, STARD3NL, ESR1, and LIPC. Examples are rs2144300 in GALNT2 in whites (P=2.29x10(-4), β=-1.85 mg/dL) and rs12595985 in FTO in African Americans (P=2.90x10(-4), β=4.52 mg/dL), both with consistent regional association (P<0.05) in the other race group. Additionally, baseline GALNT2 expression differed by rs2144300 genotype in whites (P=0.0279). In conclusion, we identified multiple gene regions associated with atenolol induced HDL-C change that were consistent across race groups, several with functional implications or prior associations with HDL-C.
- Published
- 2013
- Full Text
- View/download PDF
15. An in vitro evaluation of guanfacine as a substrate for P-glycoprotein.
- Author
-
Gillis NK, Zhu HJ, and Markowitz JS
- Abstract
Background: With a US Food and Drug Administration-labeled indication to treat attention-deficit/hyperactivity disorder (ADHD), the nonstimulant guanfacine has become the preferred α(2)-agonist for ADHD treatment. However, significant interindividual variability has been observed in response to guanfacine. Consequently, hypotheses of a contributing interaction with the ubiquitously expressed drug transporter, P-glycoprotein (P-gp), have arisen. We performed an in vitro study to determine if guanfacine is indeed a substrate of P-gp., Methods: Intracellular accumulation of guanfacine was compared between P-gp expressing LLC-PK1/MDR1 cells and P-gp-negative LLC-PK1 cells to evaluate the potential interaction between P-gp and guanfacine. Cellular retention of guanfacine was analyzed using a high-performance liquid chromatographic-ultraviolet method. Rhodamine6G, a known P-gp substrate, was included in the study as a positive control., Results: At guanfacine concentrations of 50 μM and 5 μM, intracellular accumulation of guanfacine in LLC-PK1/MDR1 cells was, 35.9% ± 4.8% and 49.0% ± 28.3% respectively, of that in LLC-PK1 cells. In comparison, the concentration of rhodamine6G, the positive P-gp substrate, in LLC-PK1/MDR1 cells was only 5% of that in LLC-PK1 cells., Conclusion: The results of the intracellular accumulation study suggest that guanfacine is, at best, a weak P-gp substrate. Therefore, it is unlikely that P-gp, or any genetic variants thereof, are a determining factor in the interindividual variability of response observed with guanfacine therapy.
- Published
- 2011
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.