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1.
Br J Clin Pharmacol ; 89(10): 3105-3115, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37276579

RESUMO

AIMS: The UK Prescribing Safety Assessment was modified for use in Australia and New Zealand (ANZ) as the Prescribing Skills Assessment (PSA). We investigated the implementation, student performance and acceptability of the ANZ PSA for final-year medical students. METHODS: This study used a mixed-method approach involving student data (n = 6440) for 2017-2019 (PSA overall score and 8 domain subscores). Data were also aggregated by medical school and included student evaluation survey results. Quantitative data were analysed using descriptive and multivariate analyses. The pass rate was established by a modified Angoff method. Thematic analyses of open-ended survey comments were conducted. RESULTS: The average pass rate was slightly higher in 2017 (89%) which used a different examination to 2018 (85%) and 2019 (86%). Little difference was identified between schools for the PSA overall performance or domain subscores. There was low intercorrelation between subscores. Most students provided positive feedback about the PSA regarding the interface and clarity of questions, but an average of 35% reported insufficient time for completion. Further, 70% on average felt unprepared by their school curricula for the PSA, which is in part explained by the low prescribing experience; 69% reported completing ≤10 prescriptions during training. CONCLUSION: The ANZ PSA was associated with high pass rates and acceptability, although student preparedness was highlighted as a concern for further investigation. We demonstrate how a collaboration of medical schools can adapt a medical education assessment resource (UK PSA) as a means for fulfilling an unmet need.


Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Nova Zelândia , Currículo , Inquéritos e Questionários , Austrália , Competência Clínica , Faculdades de Medicina
2.
Med Educ ; 56(9): 901-914, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35393668

RESUMO

BACKGROUND: Fundamental challenges exist in researching complex changes of assessment practice from traditional objective-focused 'assessments of learning' towards programmatic 'assessment for learning'. The latter emphasise both the subjective and social in collective judgements of student progress. Our context was a purposively designed programmatic assessment system implemented in the first year of a new graduate entry curriculum. We applied critical realist perspectives to unpack the underlying causes (mechanisms) that explained student experiences of programmatic assessment, to optimise assessment practice for future iterations. METHODS: Data came from 14 in-depth focus groups (N = 112/261 students). We applied a critical realist lens drawn from Bhasker's three domains of reality (the actual, empirical and real) and Archer's concept of structure and agency to understand the student experience of programmatic assessment. Analysis involved induction (pattern identification), abduction (theoretical interpretation) and retroduction (causal explanation). RESULTS: As a complex educational and social change, the assessment structures and culture systems within programmatic assessment provided conditions (constraints and enablements) and conditioning (acceptance or rejection of new 'non-traditional' assessment processes) for the actions of agents (students) to exercise their learning choices. The emergent underlying mechanism that most influenced students' experience of programmatic assessment was one of balancing the complex relationships between learner agency, assessment structures and the cultural system. CONCLUSIONS: Our study adds to debates on programmatic assessment by emphasising how the achievement of balance between learner agency, structure and culture suggests strategies to underpin sustained changes (elaboration) in assessment practice. These include; faculty and student learning development to promote collective reflexivity and agency, optimising assessment structures by enhancing integration of theory with practice, and changing learning culture by both enhancing existing and developing new social structures between faculty and the student body to gain acceptance and trust related to the new norms, beliefs and behaviours in assessing for and of learning.


Assuntos
Currículo , Estudantes , Docentes , Humanos , Aprendizagem
3.
BMC Cancer ; 16: 124, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26892430

RESUMO

BACKGROUND: Currently there are very few biomarkers to identify head and neck squamous cell carcinoma (HNSCC) cancer patients at a greater risk of recurrence and shortened survival. This study aimed to investigate whether a marker of systemic inflammation, the neutrophil-to-lymphocyte ratio (NLR), was predictive of clinical outcomes in a heterogeneous cohort of HNSCC cancer patients. METHODS: We performed a retrospective analysis to identify associations between NLR and clinicopathological features to recurrence free survival (RFS) and overall survival (OS). Univariate analysis was used to identify associations and selected variables were included in multivariable Cox regression analysis to determine predictive value. RESULTS: A total of 145 patients with stage I-IV HNSCC that had undergone radiotherapy were analysed. Seventy-six of these patients had oropharyngeal cancer and 69 had non-oropharyngeal HNSCC and these populations were analysed separately. NLR was not associated to any clinicopathological variable. On univariate analysis, NLR showed associations with RFS and OS in both sub-populations. Multivariable analysis showed patients with NLR > 5 had shortened OS in both sub-populations but NLR > 5 only predicted RFS in oropharyngeal patients. Poor performance status predicted OS in both sub-populations and current smokers had shortened OS and RFS in non-oropharyngeal patients. CONCLUSIONS: The results show patients with NLR > 5 predict for shorter overall survival. Further prospective validation studies in larger cohorts are required to determine the clinical applicability of NLR for prognostication in HNSCC patients.


Assuntos
Biomarcadores Tumorais/imunologia , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Neutrófilos/citologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Carcinoma de Células Escamosas de Cabeça e Pescoço , Análise de Sobrevida
4.
Lancet Oncol ; 15(11): e493-503, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25281468

RESUMO

Inflammation is a recognised hallmark of cancer that substantially contributes to the development and progression of malignancies. In established cancers, there is increasing evidence for the roles that local immune response and systemic inflammation have in progression of tumours and survival of patients with cancer. This knowledge provides an opportunity to target these inflammatory responses to improve patient outcomes. In this Review, we examine the complex interplay between local immune responses and systemic inflammation, and their influence on clinical outcomes, and propose potential anti-inflammatory interventions for patients with cancer.


Assuntos
Progressão da Doença , Inflamação/patologia , Inflamação/terapia , Neoplasias/patologia , Neoplasias/terapia , Antineoplásicos Hormonais/uso terapêutico , Feminino , Humanos , Imunidade Inata , Inflamação/imunologia , Masculino , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Neoplasias/imunologia , Prostatectomia/métodos , Radioterapia Conformacional/métodos , Medição de Risco , Análise de Sobrevida , Resultado do Tratamento , Conduta Expectante/métodos
5.
Am J Pharm Educ ; 88(3): 100668, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331197

RESUMO

OBJECTIVES: Poor knowledge and confidence in pharmacogenomics are key barriers to implementation. Education of future health care professionals is required to enhance appropriate use of pharmacogenomics; however, the optimal education approach is unclear. This systematic scoping review evaluates pharmacogenomic educational interventions to improve knowledge and confidence. FINDINGS: A total of 24 studies were included. Most (90%) studies delivered pharmacogenomic education to pharmacy students and consisted of didactic lectures and workshops with case studies. To supplement case studies, self or class aggregated (52%, 12 of 23), mock (43%, 10 of 23) or faculty member provided (4%, 1 of 23) pharmacogenomic data were used in the case scenarios. All studies used quantitative methods, including student assessments and scaled surveys to assess the impact of the educational intervention on knowledge and/or confidence in pharmacogenomics. On average, the educational interventions improved knowledge acquisition by 21%, confidence in pharmacogenomic data interpretation by 37%, confidence in communication of pharmacogenomic information to patients by 41% and to health care professionals by 44%. Improvement in communication with other health care professionals was greater in students involved in interprofessional learning compared to self-pharmacogenomic testing. SUMMARY: The measures used to determine the effect of educational interventions on student knowledge and confidence varied. Innovative pedagogy, specifically interactive case-based learning and simulation such as interprofessional learning, enhances the knowledge and confidence of students in pharmacogenomics. Course-embedded self-pharmacogenomic testing may offer a supplementary, interactive component to case-based learning by using real-life reports as the foundation of knowledge and confidence acquisition.


Assuntos
Educação em Farmácia , Estudantes de Farmácia , Humanos , Farmacogenética/educação , Aprendizagem , Pessoal de Saúde/educação
6.
Pharmacogenet Genomics ; 23(3): 148-55, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23324807

RESUMO

OBJECTIVE: P450 oxidoreductase (POR) is essential for cytochrome P450 (CYP) activity in humans. The POR*28 allele (A503V) has been shown to impact on in-vitro CYP-mediated metabolism, including CYP3A isoenzymes. The aim of the present study was to determine the in vivo impact of the POR*28 allele on the pharmacokinetics of the classic CYP3A phenotyping probes midazolam and erythromycin. Whereas midazolam is metabolized by both CYP3A4 and CYP3A5, erythromycin is exclusively oxidized by CYP3A4. MATERIALS AND METHODS: To assess CYP3A activity, 108 cancer patients received midazolam and 45 others underwent the erythromycin breath test. Patients were genotyped for POR*28, CYP3A4*22 and CYP3A5*3. RESULTS: In patients expressing CYP3A5, POR*28 carriers showed 45% lower midazolam metabolic ratios compared with POR*1/*1 patients (P<0.001). This is in line with a lower CYP3A5 activity toward midazolam for POR*28 carriers. In CYP3A5 nonexpressers, POR*28 had no influence on midazolam pharmacokinetics. For erythromycin, POR*28 carriership did not influence its metabolism. CONCLUSION: Our data show that the POR*28 allele is associated with a lower in vivo CYP3A5 activity, but has no effects on CYP3A4-mediated erythromycin and midazolam metabolism.


Assuntos
Citocromo P-450 CYP3A/metabolismo , Eritromicina/farmacocinética , Midazolam/farmacocinética , Feminino , Humanos , Masculino , Fenótipo
7.
Artigo em Inglês | MEDLINE | ID: mdl-36731355

RESUMO

The gut microbiome produces a range of short chain fatty acids (SCFA) crucially linked with diet and nutrition, metabolism, gastrointestinal health and homeostasis. SCFA are primarily measured using gas or liquid chromatography-mass spectrometry (LC/MS) after undergoing chemical derivatization. Here we assess the merits of a derivatization protocol using aniline and two aniline analogues (3-phenoxyaniline and 4-(benzyloxy)aniline) for the targeted LC-MS/MS quantification of nine SCFA (acetic, propionic, butyric, valeric, caproic acid, isobutyric, isovaleric, 2-methylbutyric, and 2-ethylbutyric acid). Evaluation of product ion spectra and optimization of MS detection conditions, provided superior detection sensitivity for 3-phenoxyaniline and 4-(benzyloxy)aniline compared to aniline. We developed a facile SCFA derivatization method using 3-phenoxyaniline under mild reaction conditions which allows for the simultaneous quantification of these SCFA in human stool samples in under eleven minutes using multiple reaction monitoring LC-MS/MS. The method was successfully validated and demonstrates intra- and inter-day accuracy (88.5-103% and 86.0-109%) and precision (CV of 0.55-7.00% and 0.33-9.55%) with recoveries (80.1-87.2% for LLOQ, 88.5-93.0% for ULOQ) and carry-over of (2.68-17.9%). Selectivity, stability and matrix effects were also assessed and satisfied validation criteria. Method applicability was demonstrated by analysing SCFA profiles in DNA-stabilized human stool samples from newly diagnosed colorectal cancer patients prior to surgery. The development of this improved method and its compatibility to measure SCFAs from DNA-stabilized stool will facilitate studies investigating the gut microbiome in health and disease.


Assuntos
Ácidos Graxos Voláteis , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Ácidos Graxos Voláteis/análise , Fezes/química , Ácido Acético , Compostos de Anilina/análise , Ácidos Graxos/análise
8.
Support Care Cancer ; 20(8): 1869-74, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21986674

RESUMO

BACKGROUND: Inflammatory markers are strong prognostic factors for survival in a variety of cancers. This study aimed to investigate the relationships between known inflammatory markers and their ability to predict overall survival (OS) in patients receiving docetaxel therapy. METHODS: Sixty-eight patients with advanced cancer were enrolled in a clinical trial of single agent docetaxel from 2000 to 2002. Inflammation was measured using baseline cytokine concentrations, acute phase reactant proteins and white blood cell counts. The neutrophil/lymphocyte ratio (NLR) and Glasgow Prognostic Score (GPS) were calculated. Associations between inflammatory markers and their predictive value for OS were tested. RESULTS: The majority of patients had elevated inflammatory markers (50-70%). Strong inter-relationships were observed between the different inflammatory indices. Only NLR and GPS were independently predictive of OS. A combined NLR and GPS score demonstrated 11 month differences in overall OS between patients with normal and elevated inflammatory status. Normalisation of NLR after three doses of chemotherapy was associated with significant improvement in survival. CONCLUSION: This study found that NLR predicts the clinical outcomes for patients with advanced cancer treated with docetaxel. The clinical utilisation of NLR should be validated in a larger patient population to confirm its utility.


Assuntos
Reação de Fase Aguda/etiologia , Antineoplásicos/uso terapêutico , Citocinas/sangue , Neoplasias/tratamento farmacológico , Taxoides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/metabolismo , Docetaxel , Feminino , Humanos , Inflamação/sangue , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Modelos de Riscos Proporcionais , Albumina Sérica/análise , Estatísticas não Paramétricas , Taxa de Sobrevida
9.
Nanotheranostics ; 4(4): 224-232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32923312

RESUMO

Molecular diagnostic testing of KRAS and BRAF mutations has become critical in the management of colorectal cancer (CRC) patients. Some progress has been made in liquid biopsy detection of mutations in circulating tumor DNA (ctDNA), which is a fraction of circulating cell-free DNA (cfDNA), but slow analysis for DNA sequencing methods has limited rapid diagnostics. Other methods such as quantitative PCR and more recently, droplet digital PCR (ddPCR), have limitations in multiplexed capacity and the need for expensive specialized equipment. Hence, a robust, rapid and facile strategy is needed for detecting multiple ctDNA mutations to improve the management of CRC patients. To address this significant problem, herein, we propose a new application of multiplex PCR/SERS (surface-enhanced Raman scattering) assay for the detection of ctDNA in CRC, in a fast and non-invasive manner to diagnose and stratify patients for effective treatment. Methods: To discriminate ctDNA mutations from wild-type cfDNA, allele-specific primers were designed for the amplification of three clinically important DNA point mutations in CRC including KRAS G12V, KRAS G13D and BRAF V600E. Surface-enhanced Raman scattering (SERS) nanotags were labelled with a short and specific sequence of oligonucleotide, which can hybridize with the corresponding PCR amplicons. The PCR/SERS assay was implemented by firstly amplifying the multiple mutations, followed by binding with multicolor SERS nanotags specific to each mutation, and subsequent enrichment with magnetic beads. The mutation status was evaluated using a portable Raman spectrometer where the fingerprint spectral peaks of the corresponding SERS nanotags indicate the presence of the mutant targets. The method was then applied to detect ctDNA from CRC patients under a blinded test, the results were further validated by ddPCR. Results: The PCR/SERS strategy showed high specificity and sensitivity for genotyping CRC cell lines and plasma ctDNA, where as few as 0.1% mutant alleles could be detected from a background of abundant wild-type cfDNA. The blinded test using 9 samples from advanced CRC patients by PCR/SERS assay was validated with ddPCR and showed good consistency with pathology testing results. Conclusions: With ddPCR-like sensitivity yet at the convenience of standard PCR, the proposed assay shows great potential in sensitive detection of multiple ctDNA mutations for clinical decision-making.


Assuntos
DNA Tumoral Circulante/sangue , Neoplasias Colorretais , Biópsia Líquida/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Análise Espectral Raman/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Células HCT116 , Humanos , Mutação/genética , Sensibilidade e Especificidade
10.
Clin Pharmacokinet ; 59(8): 1013-1026, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32034726

RESUMO

BACKGROUND: The presence of elevated systemic inflammation in people with advanced non-small cell lung cancer (NSCLC) is associated with significantly shorter survival following carboplatin-based chemotherapy. OBJECTIVE: This study investigated whether novel factors, such as systemic inflammation [platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR)], impact carboplatin pharmacokinetics and drug utilisation. The study also examined the ability of current and alternate dosing regimens to meet therapeutic targets. METHODS: Seventy-two people with advanced NSCLC treated with carboplatin-based (460-1050 mg) doublet chemotherapy were recruited and pharmacokinetic data (n = 61) were analysed using non-linear mixed modelling. Covariate analysis was performed to investigate the impact of standard and novel patient characteristics of carboplatin pharmacokinetics. A Monte Carlo simulation of 100,000 representative NSCLC patients evaluated the ability of the Calvert formula and novel dosing strategies to achieve the targeted therapeutic range. The associations between systemic inflammation and chemotherapy drug utilisation (cycles received, relative dose intensity (RDI) and second-line uptake) and clinical endpoints were also investigated in the pharmacokinetic cohort, and two independent cohorts of people with advanced NSCLC from the Chemotherapy Dosing in Cancer-Related Inflammation (CDCRI) database that were administered carboplatin-paclitaxel (n = 37) or carboplatin-gemcitabine (n = 358). RESULTS: In all cohorts, 25-53% of people had elevated systemic inflammation (NLR > 5 or PLR > 300). In the pharmacokinetic cohort, no patients achieved the desired therapeutic target of carboplatin. Carboplatin exposure was related to renal function, as estimated using the Cockcroft-Gault formula, albumin and inflammation (NLR). In the pharmacokinetic cohort, increasing carboplatin area under the curve (AUC) correlated with greater reductions in red blood cells and haemoglobin. In this cohort, the average measured AUC of partial responders was 2.4 mg·min/mL. Also in the pharmacokinetic cohort, only 12% of people with an NLR > 5 received four or more cycles of chemotherapy, compared with 62% of patients with an NLR ≤ 5 (p < 0.001). For people in the CDCRI cohort receiving carboplatin-gemcitabine, those with an NLR > 5 also received less cycles (four or more cycles, 41% vs. 60%; p < 0.01) as well as less second-line chemotherapy (46% vs. 60%; p = 0.02) compared with patients without inflammation. People in the pharmacokinetic cohort with an NLR > 5 had 12 months less median survival compared with people with an NLR ≤ 5 (6.5 vs. 18 months; p = 0.08). Similarly, overall survival was significantly shortened in people in the CDCRI cohort receiving carboplatin-gemcitabine with an NLR > 5 compared with those with an NLR ≤ 5 (7 vs. 12 months; p < 0.001), and Cox regression analysis showed a 1.5-fold (1.3-2.1; p < 0.001) increased hazard of death associated with the increased systemic inflammation. Simulations of the newly developed model-based and Calvert dosing assessed the ability to reach this study's proposed actual target AUC of 2.2-2.6 mg·min/mL. These showed current Calvert dosing was predicted to result in substantial overexposure in patients with high systemic inflammation. The newly developed model showed equivalent levels of carboplatin therapeutic target achievement across the spectrum of inflammation observed in the lung cancer population. CONCLUSION: An alternate model-based dosing strategy for carboplatin was developed and is predicted to result in consistent drug exposure across the population and improve attainment of therapeutic targets. Further studies of this new model are warranted in people with advanced NSCLC.


Assuntos
Carboplatina , Carcinoma Pulmonar de Células não Pequenas , Inflamação/complicações , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica , Carboplatina/farmacocinética , Carboplatina/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/uso terapêutico
11.
Methods Mol Biol ; 1989: 139-146, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31077104

RESUMO

Mass cytometry is a multi-parametric technique that offers insight into functional and biological systems at a single cell level (Tanner et al., Cancer Immunol Immunother 62:955-965, 2013). One of the major advantages of mass cytometry is the ability to measure multiple intracellular markers, including phosphorylated proteins that are part of major signaling pathways, such as NF-κB, JAK/STAT, and ERK/MAPK. Here we describe an optimized mass cytometry protocol for staining human clinical blood samples with panels that include phosphorylated antibodies.


Assuntos
Biomarcadores/análise , Citometria de Fluxo/métodos , Espectrometria de Massas/métodos , Fosfoproteínas/análise , Análise de Célula Única/métodos , Coloração e Rotulagem/métodos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Humanos , Fosfoproteínas/imunologia , Fosforilação
12.
Front Immunol ; 10: 2584, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749810

RESUMO

The immune system and inflammation plays a significant role in tumour immune evasion enhancing disease progression and reducing survival in colorectal cancer (CRC). Patients with advanced stages of colorectal cancer will all undergo treatment with cytotoxic chemotherapy which may alter the complexity of immune cell populations. This study used mass cytometry to investigate the circulating immune cell profile of advanced CRC patients following acute and chronic doses of standard cytotoxic chemotherapy and analysed seven major immune cell populations and over 20 subpopulations. Unsupervised clustering analysis of the mass cytometry data revealed a decrease in NK cells following one cycle of cytotoxic chemotherapy. Investigation into the NK sub-population revealed a decline in the CD56dim CD16+ NK cell population following acute and chronic chemotherapy treatment. Further analysis into the frequency of the NK cell sub-populations during the long-term chemotherapy treatment revealed a shift in the sub-populations, with a decrease in the mature, cytotoxic CD56dim CD16+ accompanied by a significant increase in the less mature CD56dim CD16- and CD56bright NK cell populations. Furthermore, analysis of the phosphorylation status of signalling responses in the NK cells found significant differences in pERK, pP38, pSTAT3, and pSTAT5 between the patients and healthy volunteers and remained unchanged throughout the chemotherapy. Results from this study reveals that there is a sustained decrease in the mature CD16+ NK cell sub-population frequency following long-term chemotherapy which may have clinical implications in therapeutic decision making.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Células Matadoras Naturais/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Antígeno CD56/imunologia , Citotoxinas/uso terapêutico , Feminino , Citometria de Fluxo , Proteínas Ligadas por GPI/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de IgG/imunologia
13.
Drug Metab Dispos ; 36(2): 205-16, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18218849

RESUMO

This article is a report on a symposium sponsored by the American Society for Pharmacology and Experimental Therapeutics and held at the Experimental Biology 07 meeting in Washington, DC. The presentations discussed the phenomenology, clinical consequences, and underlying mechanisms of cytochrome P450 and drug transporter regulation by inflammatory and infectious stimuli. Although considerable insights into the links between inflammatory mediators and altered hepatic drug clearance pathways have been gained from previous studies with acute inflammatory stimuli, this symposium highlighted recent advances in understanding how these processes operate in other organs and chronic inflammatory states relevant to human diseases. The development of mouse models of live bacterial infection provides excellent opportunities to explore the impact of infection on drug metabolism beyond the well characterized effects of bacterial endotoxin. Altered levels of cytochromes P450 and especially drug transporters due to inflammation in brain, intestine, and placenta have significant implications for the use of many drugs in diverse clinical settings. The consequences of inflammatory cytokine production by tumors for drug safety and efficacy in cancer patients were outlined. Repression of drug clearance pathways by tumor-derived cytokines may result in extreme toxicity to chemotherapy, compromising treatment of many cancers. It is fitting that, in honoring the career contributions and achievements of Dr. Kenneth W. Renton, this symposium reinforced the clinical relevance of this field.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Infecções/metabolismo , Inflamação/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Neoplasias/metabolismo , Animais , Sistema Enzimático do Citocromo P-450/genética , Humanos , Preparações Farmacêuticas/metabolismo , Transcrição Gênica
15.
Mol Cancer Ther ; 6(7): 1993-2002, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17620429

RESUMO

In view of our previous findings that tumor cell-derived macrophage migration inhibitory factor (MIF) increased macrophage-mediated ovarian cancer cell invasiveness in vitro, we investigated the wider significance of ovarian cancer cell-derived MIF for tumor growth, metastasis, and angiogenesis. We found that MIF is expressed in borderline and malignant ovarian tumors, and active MIF is found in malignant ascitic fluid. We next investigated the expression and function of MIF in a syngeneic ovarian cancer model. Stable knockdown of MIF in the murine ovarian cancer cell line ID8 decreased in vivo tumor burden and overall survival. Tumors arising from MIF knockdown cells had decreased proliferation and significantly increased apoptosis. This was associated with an increased phosphorylation of p53 and reduced Akt phosphorylation. MIF knockdown led to a changed cytokine profile in the ascitic microenvironment; tumor necrosis factor-alpha, interleukin-6 (IL-6), and IL-10 expression were all significantly decreased. Accompanying this decrease in cytokine expression was a significant decrease in macrophage infiltration into ascites. Additionally, MIF knockdown reduced the expression of proangiogenic cytokines vascular endothelial growth factor and keratinocyte chemoattractant (KC) and reduced the amount of endothelial cells in the malignant ascites. We conclude that autocrine production of MIF by ovarian cancer cells stimulates other cytokines, chemokines, and angiogenic factors that may promote colonization of the peritoneum and neovascularization of tumor deposits.


Assuntos
Fatores Inibidores da Migração de Macrófagos/metabolismo , Neovascularização Patológica , Neoplasias Ovarianas/irrigação sanguínea , Neoplasias Ovarianas/patologia , Animais , Ascite/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Células Endoteliais/patologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/metabolismo
16.
Clin Cancer Res ; 12(24): 7492-7, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17189422

RESUMO

PURPOSE: Many chemotherapeutic drugs have an inherent lack of safety due to interindividual variability of hepatic cytochrome P450 (CYP) 3A4 drug metabolism. This reduction in CYP3A4 in cancer patients is possibly mediated by cytokines associated with tumor-derived inflammation. We sought to examine this link by using an explant sarcoma in a novel transgenic mouse model of human CYP3A4 regulation. EXPERIMENTAL DESIGN: Engelbreth-Holm-Swarm sarcoma cells were injected into the hindlimb of transgenic CYP3A4/lacZ mice. Hepatic expression of the human CYP3A4 transgene was analyzed by direct measurement of the reporter gene product, beta-galactosidase enzyme activity. Hepatic expression of murine Cyp3a was analyzed at the mRNA, protein, and function levels. The acute phase response was assessed by examining cytokines [interleukin-6 (IL-6) and tumor necrosis factor] in serum, liver, or tumor as well as hepatic expression of serum amyloid protein P. RESULTS: Engelbreth-Holm-Swarm sarcoma elicited an acute phase response that coincided with down-regulation of the human CYP3A4 transgene in the liver as well as the mouse orthologue Cyp3a11. The reduction of murine hepatic Cyp3a gene expression in tumor-bearing mice resulted in decreased Cyp3a protein expression and consequently a significant reduction in Cyp3a-mediated metabolism of midazolam. Circulating IL-6 was elevated and IL-6 protein was only detected in tumor tissue but not in hepatic tissue. CONCLUSIONS: The current study provides a mechanistic link between cancer-associated inflammation and impaired drug metabolism in vivo. Targeted therapy to reduce inflammation may provide improved clinical benefit for chemotherapy drugs metabolized by hepatic CYP3A4 by improving their pharmacokinetic profile.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Fígado/metabolismo , Sarcoma Experimental/metabolismo , Adjuvantes Anestésicos/metabolismo , Adjuvantes Anestésicos/farmacologia , Animais , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Fígado/enzimologia , Fígado/patologia , Masculino , Camundongos , Camundongos Transgênicos , Midazolam/metabolismo , Midazolam/farmacologia , Sarcoma Experimental/genética , Sarcoma Experimental/patologia , Transgenes , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
17.
Clin Pharmacol Ther ; 102(4): 599-610, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28699186

RESUMO

Over the last decade there has been significant progress towards the development of personalized or "precision" medicine for many patients with cancer. However, there still remain subpopulations of cancer patients that do not possess a tumor mutation profile that is successfully targeted by the newer molecular anticancer drugs and further personalized approaches are needed. The presence of cancer-related systemic inflammation represents an underappreciated subpopulation of cancer patients needing personalized therapy. For ∼25% of all advanced cancer patients, regardless of histological subtype, the patients with systemic inflammation have significantly poorer response to chemotherapy and also shorter overall survival compared to those cancer patients without inflammation. The development of cancer-related systemic inflammation involves interactions between host and tumor cells that are potential new drug targets in cancer chemotherapy. In this review we discuss the challenges and clinical opportunities to develop new therapeutic strategies for this underappreciated drug target.


Assuntos
Antineoplásicos/farmacologia , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Animais , Desenho de Fármacos , Humanos , Inflamação/patologia , Terapia de Alvo Molecular , Mutação , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão/métodos , Taxa de Sobrevida
18.
Eur J Cancer ; 42(6): 745-50, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16517151

RESUMO

It is becoming more evident that many aspects of tumour promotion arise from persistent and unresolving inflammation. One of the key molecules mediating the inflammatory processes in tumour promotion is the cytokine, tumour necrosis factor-alpha (TNF-alpha). Clinically, elevated serum concentrations and increased expression of TNF-alpha are present in various pre-neoplastic and malignant diseases, compared with serum and tissue from healthy individuals. Although over the last few decades high-dose administration of TNF-alpha has been used as a cytotoxic agent, recent pre-clinical cancer models have provided critical evidence to support the link between chronic, low level TNF-alpha exposure and the acquisition of pro-malignant phenotype (i.e., increased growth, invasion and metastasis). Furthermore, sophisticated cellular systems are being utilised to dissect the crucial role TNF-alpha plays in the communication of stromal/inflammatory cells and tumour cells. Understanding the intricate roles of TNF-alpha in the process of tumour promotion will assist in the development of novel cancer therapeutics.


Assuntos
Neoplasias/etiologia , Fator de Necrose Tumoral alfa/fisiologia , Animais , Doença Crônica , Humanos , Inflamação/complicações , Inflamação/patologia , Camundongos , Camundongos Transgênicos , Modelos Animais , Necrose/patologia , Neoplasias/patologia
19.
Clin Pharmacokinet ; 45(6): 611-22, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16719542

RESUMO

OBJECTIVES: To determine the safety profile of 40 mg/m(2) docetaxel administered weekly to a mixed population of advanced cancer patients and identify predictors of toxicity and survival following treatment with weekly docetaxel in this population. PATIENTS AND METHODS: 68 patients with advanced cancer were enrolled into the study. Various patient characteristics, including inflammatory and nutritional status, docetaxel pharmacokinetics and liver function were investigated. Predictors of treatment-related toxicity and survival were analysed using multivariate logistic regression and Cox proportional hazards analysis, respectively. RESULTS: 27 patients (40%) experienced grade 3 or 4 toxicity, mainly gastrointestinal toxicities (20%), leukopenia (16%) and neutropenia (12%), during the first 8 weeks of docetaxel treatment. Docetaxel pharmacokinetics were the only predictive factor for haematological toxicity. The odds of severe haematological toxicity were approximately 9-fold higher for patients with reduced docetaxel clearance (e.g. <30 L/h). The odds of non-haematological toxicity were about 3-fold higher for patients with elevated levels of inflammatory markers: alpha(1)-acid glycoprotein (AAGP) >1.5 g/L or C-reactive protein >10 mg/L). Multivariate analysis indicated that weight loss, liver dysfunction and elevated levels of AAGP were independently significant predictors of survival. CONCLUSION: This is the first description of factors predictive of the toxicity and survival following weekly administration of docetaxel. Patients with reduced clearance of docetaxel and elevated markers of inflammation experienced worse adverse effects, while patients with weight loss, liver dysfunction and elevated markers of inflammation had worse survival.


Assuntos
Antineoplásicos Fitogênicos/efeitos adversos , Neoplasias/tratamento farmacológico , Taxoides/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Docetaxel , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Análise de Sobrevida , Taxoides/administração & dosagem , Taxoides/farmacocinética
20.
Clin Cancer Res ; 10(24): 8341-50, 2004 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-15623611

RESUMO

PURPOSE: The purpose is to identify the demographic, physiologic, and inheritable factors that influence CYP3A activity in cancer patients. EXPERIMENTAL DESIGN: A total of 134 patients (62 females; age range, 26 to 83 years) underwent the erythromycin breath test as a phenotyping probe of CYP3A. Genomic DNA was screened for six variants of suspected functional relevance in CYP3A4 (CYP3A4*1B, CYP3A4*6, CYP3A4*17, and CYP3A4*18) and CYP3A5 (CYP3A5*3C and CYP3A5*6). RESULTS: CYP3A activity (AUC(0-40 min)) varied up to 14-fold in this population. No variants in the CYP3A4 and CYP3A5 genes were a significant predictor of CYP3A activity (P > 0.2954). CYP3A activity was reduced by approximately 50% in patients with concurrent elevations in liver transaminases and alkaline phosphatase or elevated total bilirubin (P < 0.001). In a multivariate analysis, CYP3A activity was not significantly influenced by age, sex, and body size measures (P > 0.05), but liver function combined with the concentration of the acute-phase reactant, alpha-1 acid glycoprotein, explained approximately 18% of overall variation in CYP3A activity (P < 0.001). CONCLUSIONS: These data suggest that baseline demographic, physiologic, and chosen genetic polymorphisms have a minor impact on phenotypic CYP3A activity in patients with cancer. Consideration of additional factors, including the inflammation marker C-reactive protein, as well as concomitant use of other drugs, food constituents, and complementary and alternative medicine with inhibitory and inducible effects on CYP3A, is needed to reduce variation in CYP3A and treatment outcome to anticancer therapy.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Neoplasias/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Tamanho Corporal , Citocromo P-450 CYP3A , Sistema Enzimático do Citocromo P-450/genética , DNA de Neoplasias/genética , Demografia , Feminino , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/metabolismo , Orosomucoide/metabolismo , Fenótipo
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