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1.
Ann Oncol ; 31(8): 1021-1029, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32387453

RESUMO

BACKGROUND: Primary tumour location (PTL) is being adopted by clinicians to guide treatment decisions in metastatic colorectal cancer (mCRC). Here we test PTL as a predictive marker for panitumumab efficacy, and examine its relationship with an extended biomarker profile. We also examine rectal tumours as a separate location. PATIENTS AND METHODS: mCRC patients from the second-line PICCOLO trial of irinotecan versus irinotecan/panitumumab (IrPan). PTL was classified as right-PTL, left-PTL or rectal-PTL. PTL was assessed as a predictive biomarker for IrPan effect in RAS-wild-type (RAS-wt) patients (compared with irinotecan alone), then tested for independence alongside an extended biomarker profile (BRAF, epiregulin/amphiregulin (EREG/AREG) and HER3 mRNA expression). RESULTS: PTL data were available for 1180 patients (98.5%), of whom 558 were RAS-wt. High HER3 expression was independently predictive of panitumumab overall survival improvement, but PTL and EREG/AREG were not. IrPan progression-free survival (PFS) improvement compared with irinotecan was seen in left-PTL [hazard ratio (HR) = 0.61, P = 0.002) but not right-PTL (HR = 0.98, P = 0.90) (interaction P = 0.05; RAS/BRAF-wt interaction P = 0.10), or in rectal-PTL (HR = 0.82, P = 0.20) (interaction P = 0.14 compared with left-PTL; RAS/BRAF-wt interaction P = 0.04). Patients with right-PTL and high EREG/AREG or HER3 expression, had IrPan PFS improvement (high EREG/AREG HR = 0.20, P = 0.04; high HER3 HR = 0.33, P = 0.10) compared with irinotecan. Similar effect was seen for rectal-PTL patients (high EREG/AREG HR = 0.44, P = 0.03; high HER3 HR = 0.34, P = 0.05). CONCLUSIONS: RAS-wt patients with left-PTL are more likely to have panitumumab PFS advantage than those with right-PTL or rectal-PTL. However, an extended biomarker panel demonstrated significant heterogeneity in panitumumab PFS effect within a tumour location. AREG/EREG and HER3 mRNA expression identifies patients with right-PTL or rectal-PTL who achieve similar PFS effect with panitumumab as left-colon patients. Testing could provide a more reliable basis for clinical decision making. Further validation and development of these biomarkers is required to optimise routine patient care. CLINICAL TRIAL REGISTRATION: ISRCTN identifier: ISRCTN93248876.


Assuntos
Neoplasias Colorretais , Neoplasias Retais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores , Neoplasias Colorretais/tratamento farmacológico , Humanos , Mutação , Panitumumabe , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/genética , Resultado do Tratamento
2.
Ann Oncol ; 28(3): 562-568, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27993800

RESUMO

Background: To improve strategies for the treatment of BRAF-mutant advanced colorectal cancer (aCRC) patients, we examined individual data from patients treated with chemotherapy alone in three randomised trials to identify points on the treatment pathway where outcomes differ from BRAF wild-types. Patients and methods: 2530 aCRC patients were assessed from three randomised trials. End-points were progression-free survival, response rate, disease control rate, post-progression survival (P-PS) and overall survival. Treatments included first-line oxaliplatin/fluorouracil (OxFU) and second-line irinotecan. Clinicians were unaware of BRAF-status. Results: 231 patients (9.1%) had BRAF-mutant tumours. BRAF-mutation conferred significantly worse survival independent of associated clinicopathological factors known to be prognostic. Compared with wild-type, BRAF-mutant patients treated with first-line OxFU had similar DCR (59.2% versus 72%; adjusted OR = 0.76, P = 0.24) and PFS (5.7 versus 6.3 months; adjusted HR = 1.14, P = 0.26). Following progression on first-line chemotherapy, BRAF-mutant patients had a markedly shorter P-PS (4.2 versus 9.2 months, adjusted HR = 1.69, P < 0.001). Fewer BRAF-mutant patients received second-line treatment (33% versus 51%, P < 0.001), but BRAF-mutation was not associated with inferior second-line outcomes (RR adjusted OR = 0.56, P = 0.45; PFS adjusted HR = 1.01, P = 0.93). Significant clinical heterogeneity within the BRAF-mutant population was observed: a proportion (24.3%) had good first-line PFS and P-PS (both >6 months; OS = 24.0 months); however, 36.5% progressed rapidly through first-line chemotherapy and thereafter, with OS = 4.7 months. Conclusions: BRAF-mutant aCRC confers a markedly worse prognosis independent of associated clinicopathological features. Chemotherapy provides meaningful improvements in outcome throughout treatment lines. Post-progression survival is markedly worse and vigilance is required to ensure appropriate delivery of treatment after first-line progression.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adulto , Idoso , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Mutação , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Prognóstico , Resultado do Tratamento
3.
Am J Transplant ; 15(10): 2691-703, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25988811

RESUMO

Blood chimerism has been reported sporadically among visceral transplant recipients, mostly in association with graft-vs-host disease (GVHD). We hypothesized that a higher degree of mixed chimerism would be observed in multivisceral (MVTx) than in isolated intestinal (iITx) and isolated liver transplant (iLTx) recipients, regardless of GVHD. We performed a longitudinal prospective study investigating multilineage blood chimerism with flow cytometry in 5 iITx and 4 MVTx recipients up to one year posttransplant. Although only one iITx patient experienced GVHD, T cell mixed chimerism was detected in 8 out of 9 iITx/MVTx recipients. Chimerism was significantly lower in the four subjects who displayed early moderate to severe rejection. Pre-formed high-titer donor-specific antibodies, bound in vivo to the circulating donor cells, were associated with an accelerated decline in chimerism. Blood chimerism was also studied in 10 iLTx controls. Among nonsensitized patients, MVTx recipients exhibited greater T and B cell chimerism than either iITx or iLTx recipients. Myeloid lineage chimerism was present exclusively among iLTx and MVTx (6/13) recipients, suggesting that its presence required the hepatic allograft. Our study demonstrates, for the first time, frequent T cell chimerism without GVHD following visceral transplantation and a possible relationship with reduced rejection rate in MVTx recipients.


Assuntos
Rejeição de Enxerto/imunologia , Doença Enxerto-Hospedeiro/imunologia , Intestinos/transplante , Transplante de Fígado , Linfócitos T/imunologia , Quimeras de Transplante/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Citometria de Fluxo , Seguimentos , Rejeição de Enxerto/sangue , Doença Enxerto-Hospedeiro/sangue , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Quimeras de Transplante/sangue , Adulto Jovem
4.
Br J Cancer ; 110(9): 2178-86, 2014 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-24743706

RESUMO

BACKGROUND: Molecular characteristics of cancer vary between individuals. In future, most trials will require assessment of biomarkers to allocate patients into enriched populations in which targeted therapies are more likely to be effective. The MRC FOCUS3 trial is a feasibility study to assess key elements in the planning of such studies. PATIENTS AND METHODS: Patients with advanced colorectal cancer were registered from 24 centres between February 2010 and April 2011. With their consent, patients' tumour samples were analysed for KRAS/BRAF oncogene mutation status and topoisomerase 1 (topo-1) immunohistochemistry. Patients were then classified into one of four molecular strata; within each strata patients were randomised to one of two hypothesis-driven experimental therapies or a common control arm (FOLFIRI chemotherapy). A 4-stage suite of patient information sheets (PISs) was developed to avoid patient overload. RESULTS: A total of 332 patients were registered, 244 randomised. Among randomised patients, biomarker results were provided within 10 working days (w.d.) in 71%, 15 w.d. in 91% and 20 w.d. in 99%. DNA mutation analysis was 100% concordant between two laboratories. Over 90% of participants reported excellent understanding of all aspects of the trial. In this randomised phase II setting, omission of irinotecan in the low topo-1 group was associated with increased response rate and addition of cetuximab in the KRAS, BRAF wild-type cohort was associated with longer progression-free survival. CONCLUSIONS: Patient samples can be collected and analysed within workable time frames and with reproducible mutation results. Complex multi-arm designs are acceptable to patients with good PIS. Randomisation within each cohort provides outcome data that can inform clinical practice.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Medicina de Precisão , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Neoplasias Colorretais/mortalidade , Análise Mutacional de DNA , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas p21(ras) , Resultado do Tratamento
5.
Eur J Neurol ; 21(2): 299-304, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24894998

RESUMO

BACKGROUND AND PURPOSE: Progressive multifocal leukoencephalopathy (PML) is caused by reactivation of JC virus (JCV) infection due to combined host and viral factors. Anti-JCV antibodies provide a means to assess JCV exposure and stratify PML risk. The reported seroprevalence of anti-JCV antibodies varies from 39% to 91% depending on assay methodology and population studied. A two-step anti-JCV antibody assay (STRATIFY JCV™; Focus Diagnostics, Cypress, CA, USA) detected anti-JCV antibodies in approximately 55% of multiple sclerosis (MS) patients. This study describes the prevalence of anti-JCV antibodies in a large, multinational MS population. METHODS: This cross-sectional epidemiology study was designed to enroll a minimum of 2000 patients with an MS diagnosis of any type, irrespective of treatment, from Europe, Canada and Australia. Anti-JCV antibody prevalence was determined by STRATIFY JCV; the effects of demographic and disease characteristics were evaluated. RESULTS: A total of 7724 patients from 10 countries participated in the study. Overall anti-JCV antibody prevalence was 57.1% (95% confidence interval 56.0%-58.2%). Seroprevalence was significantly associated with increasing age, gender and country of current residence (P < 0.0001). No significant differences in anti-JCV antibody prevalence were associated with MS disease characteristics, including duration and type of MS and number and duration of MS therapies. CONCLUSIONS: Overall seroprevalence of anti-JCV antibodies in MS patients from Europe, Canada and Australia was consistent with previous studies using the STRATIFY JCV assay. Anti-JCV prevalence differed significantly by age, gender and country, but no geographical pattern was evident. Disease and treatment type were not associated with differences in anti-JCV antibody status.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva/epidemiologia , Esclerose Múltipla/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Leucoencefalopatia Multifocal Progressiva/sangue , Leucoencefalopatia Multifocal Progressiva/imunologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/imunologia , Estudos Soroepidemiológicos , Adulto Jovem
6.
Gene Ther ; 19(4): 365-74, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21753797

RESUMO

Transduction of exogenous T-cell receptor (TCR) genes into patients' activated peripheral blood T cells is a potent strategy to generate large numbers of specific T cells for adoptive therapy of cancer and viral diseases. However, the remarkable clinical promise of this powerful approach is still being overshadowed by a serious potential consequence: mispairing of the exogenous TCR chains with endogenous TCR chains. These 'mixed' heterodimers can generate new specificities that result in graft-versus-host reactions. Engineering TCR constant regions of the exogenous chains with a cysteine promotes proper pairing and reduces the mispairing, but, as we show here, does not eliminate the formation of mixed heterodimers. By contrast, deletion of the constant regions, through use of a stabilized Vα/Vß single-chain TCR (scTv), avoided mispairing completely. By linking a high-affinity scTv to intracellular signaling domains, such as Lck and CD28, the scTv was capable of activating functional T-cell responses in the absence of either the CD3 subunits or the co-receptors, and circumvented mispairing with endogenous TCRs. Such transduced T cells can respond to the targeted antigen independent of CD3 subunits via the introduced scTv, without the transduced T cells acquiring any new undefined and potentially dangerous specificities.


Assuntos
Imunoterapia Adotiva/métodos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T/imunologia , Transdução Genética , Animais , Complexo CD3/genética , Linhagem Celular , Dimerização , Vetores Genéticos , Humanos , Camundongos , Multimerização Proteica , Retroviridae/genética
7.
West Afr J Med ; 31(3): 198-203, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23310942

RESUMO

PURPOSE: Activation of the KRAS oncogene is implicated in colorectal carcinogenesis and mutations have been reported in 30-50% of cases. BRAF mutation, though less common, is also reported and importantly associated with shorter progression-free interval. This study aims to determine the KRAS and BRAF mutation statuses of Nigerian colorectal cancers (CRC). METHODS: Mutation analysis was carried out on archival paraffin-embedded blocks of CRC tissues. KRAS codons 12, 13 and 61 and BRAF V600E were assessed by pyrosequencing after DNA extraction from 200 cases at the Leeds Institute of Molecular Medicine, St. James's University Hospital, UK. Mutation rates and the spectra were determined. RESULTS: Pyrosequencing was successful in 112 of 200 cases. KRAS mutation in codons 12 and 13 was demonstrated in 23 of 112 cases (21%); none in codon 61. BRAF mutation in codon 600 was demonstrated in 4.5%. CONCLUSION: This study shows that 21% of Nigerian CRC patients carry a KRAS mutation; half the rate in Caucasians; and that BRAF mutation also occurs in Nigerian CRC cancers.


Assuntos
População Negra/genética , Neoplasias Colorretais/genética , Genes ras/genética , Proteínas Proto-Oncogênicas B-raf/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Códon , Neoplasias Colorretais/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Nigéria , Adulto Jovem
8.
ESMO Open ; 7(2): 100400, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35247870

RESUMO

BACKGROUND: Microsatellite instability (MSI)/mismatch repair deficiency (dMMR) is a key genetic feature which should be tested in every patient with colorectal cancer (CRC) according to medical guidelines. Artificial intelligence (AI) methods can detect MSI/dMMR directly in routine pathology slides, but the test performance has not been systematically investigated with predefined test thresholds. METHOD: We trained and validated AI-based MSI/dMMR detectors and evaluated predefined performance metrics using nine patient cohorts of 8343 patients across different countries and ethnicities. RESULTS: Classifiers achieved clinical-grade performance, yielding an area under the receiver operating curve (AUROC) of up to 0.96 without using any manual annotations. Subsequently, we show that the AI system can be applied as a rule-out test: by using cohort-specific thresholds, on average 52.73% of tumors in each surgical cohort [total number of MSI/dMMR = 1020, microsatellite stable (MSS)/ proficient mismatch repair (pMMR) = 7323 patients] could be identified as MSS/pMMR with a fixed sensitivity at 95%. In an additional cohort of N = 1530 (MSI/dMMR = 211, MSS/pMMR = 1319) endoscopy biopsy samples, the system achieved an AUROC of 0.89, and the cohort-specific threshold ruled out 44.12% of tumors with a fixed sensitivity at 95%. As a more robust alternative to cohort-specific thresholds, we showed that with a fixed threshold of 0.25 for all the cohorts, we can rule-out 25.51% in surgical specimens and 6.10% in biopsies. INTERPRETATION: When applied in a clinical setting, this means that the AI system can rule out MSI/dMMR in a quarter (with global thresholds) or half of all CRC patients (with local fine-tuning), thereby reducing cost and turnaround time for molecular profiling.


Assuntos
Neoplasias Colorretais , Instabilidade de Microssatélites , Inteligência Artificial , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Reparo de Erro de Pareamento de DNA/genética , Detecção Precoce de Câncer , Humanos
9.
Ann Oncol ; 21 Suppl 7: vii123-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20943604

RESUMO

As a consequence of new innovative therapies and therapeutic combinations, the treatment of advanced colorectal cancer is becoming increasingly complex. Validated molecular biomarkers could contribute to patient management, but until recently, none has been routinely used. With the recognition that activating mutations of the KRAS oncogene can predict resistance to anti-epidermal growth factor receptor agents, the clinical value of biomarkers in advanced colorectal cancer has been brought to the fore. Prognostic and predictive biomarkers that reflect the molecular and therapeutic complexities of advanced colorectal cancer may provide valuable information regarding likely clinical outcome and therapeutic response and thus may improve patient management and therapeutic agent selection. Such biomarkers are discussed herein.


Assuntos
Carcinoma/terapia , Neoplasias Colorretais/terapia , Tomada de Decisões , Patologia Molecular/métodos , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma/diagnóstico , Carcinoma/genética , Carcinoma/patologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Tomada de Decisões/fisiologia , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Prognóstico , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/genética
10.
Gynecol Oncol ; 109(2): 296-302, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18374970

RESUMO

BACKGROUND: The incidence of postoperative delirium (PD) in the elderly ranges between 3-60% but has never been examined in gynecologic oncology. Our goal was to identify pre, intra, and postoperative risk factors associated with the development of PD. METHODS: English speaking women of 60 years and above undergoing major surgery for suspected gynecologic malignancies were invited to participate. Enrolled patients were administered a pre and postoperative Mini-Mental State Exam (MMSE), and the postoperative Confusion Assessment Method was used to diagnosis PD. Pre, intra, and postoperative clinicopathology parameters were collected. Statistics included the Pearson chi-squared tests and multivariate logistic regression. RESULTS: Eighteen of a total of 103 patients (17.5%) developed PD. Univariate analysis revealed significant associations (p<0.05) between the development of delirium and age, albumin level, Charlson comorbidity index, performance status, dementia, level of education, number of pre and postoperative medications, prolonged oxygen or Foley catheter usage (>2 d), increased narcotic use (above standard regimens), postoperative transfusion, bed restriction and change in MMSE scores (pre vs. post). Using multivariate logistic regression analysis, older patients (p=0.0002), on multiple medications (p=0.008), given additional narcotic doses (p<0.0001) were at highest risk for the development of delirium. Intraoperative parameters were not correlated with outcome. CONCLUSIONS: PD is a common complication in older women undergoing major gynecologic surgery. Increased narcotics, age, and preoperative medications were strongly associated with this adverse event. Prevention needs to focus on i) identifying patients at higher risk for PD based on preoperative parameters, and ii) eliminating known postoperative risk factors.


Assuntos
Neoplasias dos Genitais Femininos/cirurgia , Procedimentos Cirúrgicos em Ginecologia , Doença de Parkinson/epidemiologia , Doença de Parkinson/etiologia , Complicações Pós-Operatórias , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Incidência , Modelos Logísticos , Pessoa de Meia-Idade , Entorpecentes/administração & dosagem , Entorpecentes/efeitos adversos , Medição de Risco , Fatores de Risco
11.
Maturitas ; 60(1): 31-41, 2008 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-18486367

RESUMO

OBJECTIVE: The vagina is a complex tubular structure that has reproductive, support and barrier functions. These depend on the cytoarchitecture of the vaginal cells, which is controlled by key proteins. Cytoskeletal proteins determine cell polarity and membrane specializations by integrating the actin cytoskeleton with cell membranes. This integration is the domain of cytoskeletal proteins including the MERM protein family (moesin-ezrin-radixin-Merlin). Nothing is known about the cyto-localization of the MERM's in the vaginal epithelium or how it influences the cytoarchitecture of the vaginal epithelium and stroma. DESIGN: Full-thickness human vaginal fornix samples were obtained from 20 normal human specimens obtained at surgery for pelvic relaxation. Light- and electron microscopical immunohistochemistry (IHC) were used to identify and study activation and cellular localization of immuno-reactive-ezrin (ir-ezrin), a prototypical MERM. RESULTS: Ir-ezrin was identified in the stratified squamous vaginal epithelium and connective tissue (fibroblasts, blood vessels and leucocytes). "H" scoring indicated that ir-ezrin staining is denser in the vaginal epithelium than in other layers, that the ir-ezrin staining was associated with increased keratinization and with the size of the tight junctions (p<0.01). Both the amounts and localization of ir-ezrin were associated with high levels of estrogen, identified by the menstrual history and keratinization of the superficial vaginal epithelium. The density of stromal ir-ezrin was increased in the presence of dense epithelial keratinization. Immuno-reactive-ezrin staining was most pronounced near the cell membranes of both keratinized and non-keratinized epithelium, indicating that ezrin activation (unfolding and movement to the membrane) had occurred. Ultra-structural examination of the epithelium showed intra-cellular ir-ezrin to be localized to junctional complexes that have been associated with decreased mucosal penetration by microorganisms. Ir-ezrin was widely distributed throughout stromal fibro-muscular cell, vessels and immunocytes. CONCLUSIONS: MERM's, represented by ezrin, are widely present in the vaginal wall. This has implications for the strength and resilience of this tubular structure and may be the case in other internal genital tissues. Ezrin's localization and association with cell specializations indicate that in the vagina, as in other tissues, ezrin likely modulates vaginal cell-cell interactions including the changing vaginal cellular interface with the external environment, the regulation of the elasticity of the vagina, and the regulation of microbial and chemical traffic that determine the pH and microbial environment of the vagina. In other work we have shown that ezrin expression is induced by estradiol. The increase of ir-ezrin staining during the appearance of keratinization and maturation of the vaginal cytology indicates that estrogen may regulate vaginal ezrin and thereby the properties of the vaginal wall and epithelium.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Vagina/citologia , Vagina/metabolismo , Adulto , Comunicação Celular/fisiologia , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Elasticidade , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Estrogênios/fisiologia , Feminino , Humanos , Pessoa de Meia-Idade , Vagina/ultraestrutura
12.
Protein Eng Des Sel ; 19(6): 255-64, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16549400

RESUMO

Yeast display provides a system for engineering high-affinity proteins using a fluorescent-labeled ligand and fluorescence-activated cell sorting (FACS). In cases where it is difficult to obtain purified ligands, or to access FACS instrumentation, an alternative selection strategy would be useful. Here we show that yeast expressing high-affinity proteins against a mammalian cell surface ligand could be rapidly selected by density centrifugation. Yeast cell-mammalian cell conjugates were retained at the density interface, separated from unbound yeast. High-affinity T cell receptors (TCRs) displayed on yeast were isolated using antigen presenting cells that expressed TCR ligands, peptides bound to products of the major histocompatibility complex (MHC). The procedure yielded 1000-fold enrichments, in a single centrifugation, of yeast displaying high-affinity TCRs. We defined the affinity limits of the method and isolated high-affinity TCR mutants against peptide variants that differed by only a single residue. The approach was applied to TCRs specific for class I or class II MHC, an important finding since peptide-class II MHC ligands have been particularly difficult to purify. As yeast display has also been used previously to identify antigen-specific antibodies, the method should be applicable to the selection of antibodies, as well as TCRs, with high-affinity for tumor cell-surface antigens.


Assuntos
Evolução Molecular Direcionada , Proteínas Fúngicas/genética , Complexo Principal de Histocompatibilidade , Engenharia de Proteínas/métodos , Receptores de Antígenos de Linfócitos T/metabolismo , Leveduras/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Citometria de Fluxo/métodos , Corantes Fluorescentes/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Biblioteca Gênica , Antígenos de Histocompatibilidade Classe II/química , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Ligantes , Mutação , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/isolamento & purificação
13.
J Natl Cancer Inst ; 83(1): 51-5, 1991 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-1984518

RESUMO

A phase I trial of piritrexim was conducted by use of a prolonged, low-dose oral schedule. A number of different regimens were tested, including daily dosing for 21 days followed by 7 days of no drug therapy; continuous dosing; and daily dosing for 5 of 7 days for 3 consecutive weeks followed by a week of rest. Dose escalation was accomplished by increasing the dosing frequency from once a day to twice a day and then to three times a day and by increasing the number of days of administration. Fifty-one patients with advanced cancer were entered in the study. One hundred twenty-four (96%) of 129 courses were considered assessable. Myelosuppression proved to be the dose-limiting toxic effect. Other toxic effects included stomatitis, nausea and vomiting, anorexia, diarrhea, skin rash, fatigue, and elevation of liver transaminase levels. Antitumor activity was observed in patients with melanoma and bladder cancer, and disease stabilization occurred in those with sarcoma and pheochromocytoma. The recommended dosing schedule for phase II clinical trials is 25 mg three times a day for 5 days for 3 consecutive weeks followed by 1 week of no drug therapy.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Pirimidinas/uso terapêutico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/administração & dosagem , Antineoplásicos/sangue , Antineoplásicos/toxicidade , Relação Dose-Resposta a Droga , Avaliação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pirimidinas/administração & dosagem , Pirimidinas/sangue , Pirimidinas/toxicidade
14.
Cancer Res ; 37(4): 980-3, 1977 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-139205

RESUMO

One hundred thirty-eight adults with advanced cancers were treated with Baker's Antifol. The complete response + partial response rate was only 10%. Best responses were obtained in 31 patients with lung adenocarcinoma (complete response + partial response, 13%), in 25 patients with colorectal carcinoma (partial response, 16%), and in 6 patients with renal cell carcinoma (partial response, 50%). Two partial responses occurred in 15 patients with squamous cancer. No significant responses were seen in 27 patients with other adenocarcinomas, 13 with sarcomas, 14 with melanomas, and 8 with miscellaneous tumors. The most frequent toxicities were dermatitis, stomatitis, gastrointestinal symptoms, and mild myelosuppression. The incidence of dermatitis was significantly decreased by shortening the schedule of Baker's Antifol administration from 5 to 3 days. Baker's Antifol has some degree of antitumor activity, and studies of combination of this agent with other effective chemotherapeutic agents are indicated.


Assuntos
Antagonistas do Ácido Fólico/uso terapêutico , Neoplasias/tratamento farmacológico , Triazinas/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adolescente , Adulto , Idoso , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias do Colo/tratamento farmacológico , Toxidermias/etiologia , Feminino , Antagonistas do Ácido Fólico/administração & dosagem , Antagonistas do Ácido Fólico/efeitos adversos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Neoplasias Renais/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Melanoma/tratamento farmacológico , Pessoa de Meia-Idade , Neoplasias Retais/tratamento farmacológico , Remissão Espontânea , Sarcoma/tratamento farmacológico , Estomatite/induzido quimicamente , Triazinas/administração & dosagem
15.
J Clin Oncol ; 9(4): 625-30, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2066758

RESUMO

Twenty-two patients with advanced colorectal carcinoma were enrolled in this study. Ten patients had received prior chemotherapy that included the combination of fluorouracil (5-FU) and leucovorin (LV). All patients required subcutaneous port insertion and portable external infusion pumps to allow outpatient treatment. 5-FU (2,600 mg/m2) was administered concurrently with LV (500 mg/m2) over 24 hours of continuous infusion. The mean steady-state plasma concentration of 5-FU was 10 mumol/L (range, 7 to 14 mumol/L). The 5-FU dose was based on our previous phase I study, in which maximum-tolerated dose (MTD) of 5-FU was determined to be 2,600 mg/m2 in combination with a fixed dose of LV at 500 mg/m2. The treatment was repeated weekly. Twenty-two patients received a total of 560 courses of treatment. Eleven instances of grade 2-3 toxicity were observed: diarrhea (five), stomatitis (three), hand/foot syndrome (three). The overall objective response was 45% (10 of 22) and among previously untreated patients was 58%. Three of the responders achieved complete response (CR), with lung and liver as the metastatic sites. The median duration of survival for the previously untreated patients was not reached at 22 months, and was 10 months for the previously treated patients. These results suggest that short-term infusional therapy of 5-FU and LV in patients with advanced metastatic colorectal cancer generates acceptable toxicity, with equivalent or superior survivability in previously treated and untreated patients versus alternative methods of administration of the two agents.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Assistência Ambulatorial , Neoplasias Colorretais/sangue , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/sangue , Humanos , Infusões Intravenosas , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Taxa de Sobrevida
16.
J Clin Oncol ; 10(1): 134-42, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1727915

RESUMO

PURPOSE: This multicenter, double-blind, randomized trial was performed to determine the efficacy and safety of pamidronate disodium (APD) in comparison to etidronate disodium (EHDP) in the treatment of cancer-related hypercalcemia. PATIENTS AND METHODS: Sixty-five male and female adult patients with cancer and corrected calcium levels of greater than or equal to 12.0 mg/dL after 24 hours of hydration were randomized to receive either 60 mg APD given as a single 24-hour infusion or 7.5 mg/kg EHDP given as a 2-hour infusion daily for 3 days. RESULTS: APD normalized corrected calcium levels in 70% (21 of 30) of patients, whereas EHDP did so in 41% (14 of 34) of patients (P = .026). The mean corrected serum calcium level decreased from 14.6 to 10.5 mg/dL in the APD-treated group and from 13.8 to 11.6 mg/dL in the EHDP-treated group within the first week of treatment. There was no difference in response to APD in patients without versus those with bone metastases (78% v 67%). Both drugs were well tolerated. CONCLUSION: This study demonstrated that a single 60-mg infusion of APD is safe and more effective than EHDP given at the dose of 7.5 mg/kg for 3 days in the treatment of cancer-related hypercalcemia.


Assuntos
Difosfonatos/uso terapêutico , Ácido Etidrônico/uso terapêutico , Hipercalcemia/tratamento farmacológico , Neoplasias/complicações , Adulto , Idoso , Análise de Variância , Cálcio/sangue , Difosfonatos/administração & dosagem , Difosfonatos/efeitos adversos , Método Duplo-Cego , Ácido Etidrônico/administração & dosagem , Ácido Etidrônico/efeitos adversos , Feminino , Humanos , Hipercalcemia/etiologia , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Pamidronato
17.
J Clin Oncol ; 1(4): 247-50, 1983 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6686848

RESUMO

Twenty-seven patients (25 males and 2 females) with histologically confirmed, unresectable, or metastatic non-small cell lung cancer were entered on a combination chemotherapy protocol including cisplatinum and vinblastine sulfate (DDP)(VLB). Patients had to have measurable disease as defined by the presence of two clearly measurable perpendicular diameters, be untreated with either chemotherapy or radiation therapy, and give informed consent to be eligible for study entry. The median age was 57 yr and the median performance status was 70 (Karnofsky scale); 10 patients had epidermoid carcinoma, 9 adenocarcinoma, 4 large cell carcinoma, and 4 undifferentiated carcinoma. All patients had intrathoracic disease, 12 also had extrathoracic lymph node involvement, 8 bone involvement, 2 liver metastasis, and 2 central nervous system metastasis prior to beginning chemotherapy; 9 patients had involvement of one site, 12 of two sites, 5 of three sites, and 1 of four sites. Cisplatinum was given as a short intravenous infusion of 120 mg/m2 on days 1 and 28, and then every 6 wk. Vinblastine was administered as an intravenous injection of 8 mg/m2 on days 1, 14, and 28, and then every 3 wk. Patients were evaluated prior to each course of cisplatinum. If progression occurred, therapy was discontinued. If stabilization or response was noted, then therapy was continued until intolerable toxicity or progression supervened. Every patient entered is considered evaluable for toxicity and response. There were no complete remissions; 14 patients achieved a partial response, 3 had a minimal response, 5 had stabilization of their disease, 1 had disease progression, and 4 are considered to have had drug deaths. Responses were seen after the first cisplatinum course in 13 patients and after the second in 1. Toxicities seen were universal nausea and vomiting; elevation of creatinine occurred in 6 patients, ranging from 2.1 to 14.6 mg/dl, and was clinically significant in 2 patients. Myelosuppression, with a leukocyte nadir of less than 3.0 X 10(9)l in 10 cases and platelet nadir of less than 100.0 X 10(9)l was seen in 5 cases and partial hearing deficit occurred in 2 patients. Median survival was 22 wk for the whole group (24 wk for the whole group if the 4 early drug deaths are excluded). Median survival was 26 wk for responding patients and 13 wk for nonresponding patients (remains the same if the early deaths are excluded from the latter group).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Avaliação de Medicamentos , Feminino , Humanos , Infusões Parenterais , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Pancitopenia/induzido quimicamente , Fatores de Tempo , Vimblastina/administração & dosagem
18.
J Clin Oncol ; 5(11): 1725-30, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2824706

RESUMO

Non-small-cell lung cancer (NSCLC) patients with locally advanced or metastatic measurable disease were given a combination of cisplatin, 200 mg/m2 divided in five daily doses, and simultaneously, vinblastine, 7.5 mg/m2 as a continuous intravenous (IV) infusion over five days. Five courses of chemotherapy were planned. Afterwards or on progression, patients were randomized to receive maximally tolerated radiation to all sites of disease v observation only. Forty males and seven females were entered. Median age was 60 years (range, 37 to 74), median Karnofsky performance status was 70 (range, 30 to 90). Five patients had previous brain radiation therapy for metastatic disease, all others were previously untreated. Side effects in the 87 courses of chemotherapy administered included leukopenia (WBC less than 1,000/microL following nine courses) and thrombocytopenia (platelets less than 20,000/microL following four courses). Ten patients became septic, nine of them while leukopenic. Elevations of serum creatinine followed eight courses; in all cases the level was less than 3.0 mg/dL. Nausea and vomiting were mild to moderate. Five patients experienced mild hypoacusis and six had sensory polyneuropathy. The deaths of three patients were considered drug-related. The response rate was 28%. The median survival for the group was 22 weeks, 63.2 weeks for responders and 17.9 weeks for nonresponders. Twenty-six patients received radiation therapy, 16 randomized to this arm as planned, ten to palliate symptoms. Median survival of all irradiated patients was 24.8 weeks. Seven responders to chemotherapy were randomized to receive radiotherapy; their median survival was 25 weeks. In six responders randomized not to receive radiation, the median survival was 77.8 weeks (P greater than .3). Among nonresponding patients, the median survival of those radiated was 22.2 weeks, while that of nonradiated patients was 11 weeks. This regimen is cumbersome and toxic. It has offered no major survival benefits, or improvement in response rates, therefore, we do not recommend it for the standard treatment of NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Cisplatino/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Vimblastina/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Cisplatino/efeitos adversos , Avaliação de Medicamentos , Feminino , Humanos , Recém-Nascido , Infusões Intravenosas , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/radioterapia , Masculino , Pessoa de Meia-Idade , Gravidez , Dosagem Radioterapêutica , Distribuição Aleatória , Fatores de Tempo , Vimblastina/efeitos adversos
19.
Endocrinology ; 139(4): 1546-55, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9528933

RESUMO

CRH, the principal regulator of the hypothalamic-pituitary-adrenal axis and modulator of autonomic nervous system activity, also participates in the regulation of appetite and energy expenditure. Antalarmin, a pyrrolopyrimidine compound, antagonizes CRH type 1 receptor-mediated effects of CRH, including pituitary ACTH release, stress behaviors, and acute inflammation. We administered antalarmin chronically to evaluate its effects on hypothalamic-pituitary-adrenal axis function and metabolic status. Adult male rats were treated twice daily with 20 mg/kg of i.p. antalarmin or placebo over 11 days. The animals were weighed; plasma ACTH, corticosterone, leptin, and blood glucose levels were determined; and morphometric analyses were performed to determine adrenal size and structure, including sizing, histochemistry, immunohistochemistry, and electron microscopy. Leptin messenger RNA expression in peripheral fat was analyzed by Northern blot. Antalarmin decreased plasma ACTH (mean +/- SD, 2.62 +/- 0.063 pg/ml) and corticosterone concentrations (10.21 +/- 1.80 microg/dl) compared with those in vehicle-treated rats [respectively, 5.3 +/- 2.0 (P < 0.05) and 57.02 +/- 8.86 (P < 0.01)]. Antalarmin had no significant effect on body weight, plasma leptin, or blood glucose concentrations or fat cell leptin messenger RNA levels. The width of the adrenal cortex of animals treated with antalarmin was reduced by 31% compared with that in controls without atrophy of the gland. On the ultrastructural level, adrenocortical cells were in a hypofunctional state characterized by reduced vascularization, increased content of lipid droplets, and tubulovesicular mitochondria with fewer inner membranes. The apoptotic rate was increased in the outer zona fasciculata of animals treated with the antagonist (26.6 +/- 3.58%) compared with that in placebo-treated controls (6.8 +/- 0.91%). We conclude that chronic administration of antalarmin does not affect body weight, carbohydrate metabolism, or leptin expression, whereas it reduces adrenocortical function mildly, without anatomical, clinical, or biochemical evidence of causing adrenal atrophy. These results are promising for future uses of such an antagonist in the clinic.


Assuntos
Glândulas Suprarrenais/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Metabolismo/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Pirimidinas/farmacologia , Pirróis/farmacologia , Receptores de Hormônio Liberador da Corticotropina/antagonistas & inibidores , Tecido Adiposo/química , Glândulas Suprarrenais/fisiologia , Glândulas Suprarrenais/ultraestrutura , Hormônio Adrenocorticotrópico/sangue , Animais , Apoptose , Northern Blotting , Corticosterona/sangue , Leptina , Masculino , Microscopia Eletrônica , Hipófise/fisiologia , Hipófise/ultraestrutura , Proteínas/genética , Proteínas/metabolismo , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
20.
Int J Radiat Oncol Biol Phys ; 22(3): 511-4, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1735689

RESUMO

Twenty-eight patients with refractory advanced malignancies were treated with a 24 hr infusion of 5-fluorouracil (5-FU), Leucovorin (LV), and N-(phosphonacetyl)-L-aspartic acid (PALA) weekly. Twenty-seven patients were evaluable for the assessment of toxicity and anti-tumor activity. PALA was administered as intravenous bolus over 15 min at a fixed dose, 250 mg/m2 24 hr before the start of 5-FU and LV infusions. 5-FU was initially administered at 750 mg/m2 and was incrementally increased to 2600 mg/m2. LV was administered in a fixed dose of 500 mg/m2 concurrently with 5-FU over a 24-hr period. The course was repeated weekly. Diarrhea, stomatitis, nausea, and vomiting were among dose-limiting toxic effects. Other toxicities observed were hand-foot syndrome, hair loss of scalp/eyelashes, overall weakness, rhinitis, and chemical conjunctivitis. Maximum tolerated dose (MTD) of 5-FU in this combination and schedule was 2600 mg/m2. Seven of 14 patients treated at 2600 mg/m2 were able to tolerate the chemotherapy on a weekly basis without interruption. The other seven patients required dose de-escalation, a majority of whom contained 5-FU at a dose of 2100 mg/m2. Twenty-three of 27 patients had been previously treated. Eight patients achieved a partial response, all of whom were previously treated, except three patients. A complete response was observed in a patient with pancreatic carcinoma, previously untreated. Overall response rate for the patients who were treated at the 5-FU dose of 2100 mg/m2 or 2600 mg/m2 is 9 of 18 patients (50%).


Assuntos
Ácido Aspártico/análogos & derivados , Fluoruracila/administração & dosagem , Leucovorina/administração & dosagem , Neoplasias/tratamento farmacológico , Ácido Fosfonoacéticos/análogos & derivados , Adulto , Idoso , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Ácido Aspártico/administração & dosagem , Ácido Aspártico/efeitos adversos , Avaliação de Medicamentos , Feminino , Fluoruracila/efeitos adversos , Humanos , Infusões Intravenosas , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Ácido Fosfonoacéticos/administração & dosagem , Ácido Fosfonoacéticos/efeitos adversos
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