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1.
Prim Care Diabetes ; 17(5): 429-435, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37419770

RESUMO

AIMS: Diabetic retinopathy (DR) remains the leading cause of vision impairment among working-age adults in the United States. The Veterans Health Administration (VA) supplemented its DR screening efforts with teleretinal imaging in 2006. Despite its scale and longevity, no national data on the VA's screening program exists since 1998. Our objective was to determine the influence of geography on diabetic retinopathy screening adherence. METHODS: Setting: VA national electronic medical records. STUDY POPULATION: A national cohort of 940,654 veterans with diabetes (defined as two or more diabetes ICD-9 codes (250.xx)) without a history of DR. EXPOSURES: 125 VA Medical Center catchment areas, demographics, comorbidity burden, mean HbA1c levels, medication use and adherence, as well as utilization and access metrics. MAIN OUTCOME MEASURE: Screening for diabetic retinopathy within the VA medical system within a 2-year period. RESULTS: Within a 2-year time frame 74 % of veterans without a history of DR received retinal screenings within the VA system. After adjustment for age, gender, race-ethnic group, service-connected disability, marital status, and the van Walraven Elixhauser comorbidity score, the prevalence of DR screening varied by VA catchment area with values ranging from 27 % to 86 %. These differences persisted after further adjusting for mean HbA1c level, medication use and adherence as well as utilization and access metrics. CONCLUSIONS: The wide variability in DR screening across 125 VA catchment areas indicates the presence of unmeasured determinants of DR screening. These results are relevant to clinical decision making in DR screening resource allocation.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Adulto , Humanos , Estados Unidos/epidemiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Saúde dos Veteranos , Hemoglobinas Glicadas , Programas de Rastreamento/métodos , Instalações de Saúde
2.
Eur J Cancer Care (Engl) ; 31(6): e13661, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35851704

RESUMO

OBJECTIVE: Avoidance of colorectal cancer (CRC) screening is well documented with emotional barriers deterring screening intention and uptake. However, the assessment of such aversion is limited by the available instruments focusing on siloed emotions or screening procedures, limiting relevance to the complete process of decision-making in the CRC context. METHODS: To address this gap, psychometric properties of the newly developed Aversion to Bowel Cancer Screening Scale (ABCSS) were assessed using data from 640 CRC screening eligible asymptomatic community members. Item review and piloting reduced 179 items to the initial 29-item scale. Using a holdout sample technique, exploratory and confirmatory factor analysis, reliability and validity checks were conducted. RESULTS: A three-factor model (Fecal Occult Blood Test [FOBT] Aversion, Colonoscopy Aversion and Health Conscientiousness) with 21 items was identified. Analyses of the 21-item ABCSS indicated excellent reliabilities for the scale and subscales (α = .91 to .95). Correlations with relevant existing measures, intention and behaviour indicated good construct validity. CONCLUSION: The ABCSS is a valid measure of aversion to CRC screening for asymptomatic community members facing the decision to undertake CRC screening. This instrument may provide a more comprehensive understanding of the decision-making process for CRC screening.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Humanos , Detecção Precoce de Câncer/psicologia , Psicometria , Reprodutibilidade dos Testes , Sangue Oculto , Programas de Rastreamento/métodos , Colonoscopia/psicologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/psicologia
3.
Pract Radiat Oncol ; 12(1): e49-e55, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34464743

RESUMO

During the last decade, radiation oncology departments have integrated magnetic resonance imaging (MRI) equipment, procedures, and expertise into their practices. MRI safety is an important consideration because a large percentage of patients receiving radiation therapy have histories of multiple surgeries and implanted devices. However, MRI safety guidelines and workflows were traditionally designed for radiology departments. This report presents an MR safety program designed for a radiation oncology department to address its specific needs.


Assuntos
Radioterapia (Especialidade) , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
4.
Int J Health Geogr ; 20(1): 10, 2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33639940

RESUMO

BACKGROUND: Diabetes is a public health burden that disproportionately affects military veterans and racial minorities. Studies of racial disparities are inherently observational, and thus may require the use of methods such as Propensity Score Analysis (PSA). While traditional PSA accounts for patient-level factors, this may not be sufficient when patients are clustered at the geographic level and thus important confounders, whether observed or unobserved, vary by geographic location. METHODS: We employ a spatial propensity score matching method to account for "geographic confounding", which occurs when the confounding factors, whether observed or unobserved, vary by geographic region. We augment the propensity score and outcome models with spatial random effects, which are assigned scaled Besag-York-Mollié priors to address spatial clustering and improve inferences by borrowing information across neighboring geographic regions. We apply this approach to a study exploring racial disparities in diabetes specialty care between non-Hispanic black and non-Hispanic white veterans. We construct multiple global estimates of the risk difference in diabetes care: a crude unadjusted estimate, an estimate based solely on patient-level matching, and an estimate that incorporates both patient and spatial information. RESULTS: In simulation we show that in the presence of an unmeasured geographic confounder, ignoring spatial heterogeneity results in increased relative bias and mean squared error, whereas incorporating spatial random effects improves inferences. In our study of racial disparities in diabetes specialty care, the crude unadjusted estimate suggests that specialty care is more prevalent among non-Hispanic blacks, while patient-level matching indicates that it is less prevalent. Hierarchical spatial matching supports the latter conclusion, with a further increase in the magnitude of the disparity. CONCLUSIONS: These results highlight the importance of accounting for spatial heterogeneity in propensity score analysis, and suggest the need for clinical care and management strategies that are culturally sensitive and racially inclusive.


Assuntos
Grupos Raciais , População Branca , Viés , Humanos , Pontuação de Propensão , Análise Espacial
5.
Cancer ; 126(18): 4168-4176, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32639597

RESUMO

BACKGROUND: Among patients with cervical cancer, little is known about the significance of persistent human papillomavirus (HPV) expression after chemoradiation (CRT). This study evaluated associations between early posttreatment HPV clearance and patient outcomes with an added focus on the value of posttherapy positron emission tomography (PET) imaging. METHODS: Included patients underwent pretreatment testing indicating a high-risk HPV infection and posttreatment testing with a messenger RNA (mRNA)-based genital swab after CRT. Posttherapy responses were stratified on the basis of HPV mRNA detection into an early clearance (EC) group (no mRNA) and a persistent expression (PE) group (detectable mRNA) on the basis of an evaluation at a median of 6 weeks after therapy. The Kaplan-Meier method was used to compare outcomes, and multivariable analysis was used to identify predictors of outcomes. RESULTS: Seventy-two of the 97 eligible patients (74.2%) had EC. The mean follow-up time was 25 months (range, 4-56 months), and 2-year pelvic control (76.9% vs 50.2%; P = .01) and overall survival (OS; 80.9% vs 52.2%; P < .01) were superior among EC patients. In the multivariable analysis, EC predicted for improved survival (hazard ratio [HR] for mortality, 0.46; 95% confidence interval [CI], 0.21-0.96; P = .047), as did a complete response (CR) on posttherapy PET (HR for less than a CR on PET, 6.17; 95% CI, 2.58-14.72; P < .01). In a subset analysis of patients with a posttherapy PET CR, HPV clearance retained prognostic significance (2-year OS, 95.6% with EC vs 66.7% with PE; P = .04), whereas PE patients without a PET CR had the worst survival (35.9%; P < .01 for trend). CONCLUSIONS: Early posttherapy clearance of HPV is associated with improved survival in cervical cancer. Evaluating HPV expression at this 6-week time point provides prognostic information beyond posttherapy PET imaging and may aid in risk stratification and decisions for treatment escalation.


Assuntos
Papillomaviridae/patogenicidade , Infecções por Papillomavirus/terapia , Neoplasias do Colo do Útero/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
6.
Clin Cancer Res ; 25(16): 4955-4965, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31142501

RESUMO

PURPOSE: mAbs including cetuximab can induce antibody-dependent cellular cytotoxicity (ADCC) and cytokine production mediated via innate immune cells with the ability to recognize mAb-coated tumors. Preclinical modeling has shown that costimulation of natural killer (NK) cells via the Fc receptor and the IL12 receptor promotes NK-cell-mediated ADCC and production of cytokines. PATIENTS AND METHODS: This phase I/II trial evaluated the combination of cetuximab with IL12 for the treatment of EGFR-expressing head and neck cancer. Treatment consisted of cetuximab 500 mg/m2 i.v. every 2 weeks with either 0.2 mcg/kg or 0.3 mcg/kg IL12 s.c. on days 2 and 5 of the 2-week cycle, beginning with cycle 2. Correlative studies from blood draws obtained prior to treatment and during therapy included measurement of ADCC, serum cytokine, and chemokine analysis, determination of NK cell FcγRIIIa polymorphisms, and an analysis of myeloid-derived suppressor cell (MDSC) frequency in peripheral blood. RESULTS: The combination of cetuximab and IL12 was well tolerated. No clinical responses were observed, however, 48% of patients exhibited prolonged progression-free survival (PFS; average of 6.5 months). Compared with patients that did not exhibit clinical benefit, patients with PFS >100 days exhibited increased ADCC as therapy continued compared with baseline, greater production of IFNγ, IP-10, and TNFα at the beginning of cycle 8 compared with baseline values and had a predominance of monocytic MDSCs versus granulocytic MDSCs prior to therapy. CONCLUSIONS: Further investigation of IL12 as an immunomodulatory agent in combination with cetuximab in head and neck squamous cell carcinoma is warranted.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais , Cetuximab/administração & dosagem , Citocinas/biossíntese , Esquema de Medicação , Feminino , Humanos , Interleucina-12/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Metástase Neoplásica , Estadiamento de Neoplasias , Polimorfismo Genético , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Resultado do Tratamento
7.
J Clin Oncol ; 35(13): 1437-1443, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28418267

RESUMO

Purpose Therapeutic targeting of Bruton tyrosine kinase (BTK) with ibrutinib in chronic lymphocytic leukemia has led to a paradigm shift in therapy, and relapse has been uncommon with current follow-up. Acquired mutations in BTK and PLCG2 can cause relapse, but data regarding the prevalence and natural history of these mutations are limited. Patients and Methods Patients accrued to four sequential studies of ibrutinib were included in these analyses. Deep sequencing for BTK and PLCG2 was performed retrospectively on patients who experienced relapse and prospectively on a screening population. Results With a median follow-up time of 3.4 years, the estimated cumulative incidence of progression at 4 years is 19% (95% CI, 14% to 24%). Baseline karyotypic complexity, presence of del(17)(p13.1), and age less than 65 years were risk factors for progression. Among patients who experienced relapse, acquired mutations of BTK or PLCG2 were found in 85% (95% CI, 71% to 94%), and these mutations were detected an estimated median of 9.3 months (95% CI, 7.6 to 11.7 months) before relapse. Of a group of 112 patients examined prospectively, eight patients have experienced relapse, and all of these patients had acquired resistance mutations before relapse. A resistance mutation was detected in an additional eight patients who have not yet met criteria for clinical relapse. Conclusion Relapse of chronic lymphocytic leukemia after ibrutinib is an issue of increasing clinical significance. We show that mutations in BTK and PLCG2 appear early and have the potential to be used as a biomarker for future relapse, suggesting an opportunity for intervention.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/enzimologia , Proteínas Tirosina Quinases/genética , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adenina/análogos & derivados , Adulto , Tirosina Quinase da Agamaglobulinemia , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Pessoa de Meia-Idade , Fosfolipase C gama/genética , Piperidinas , Proteínas Tirosina Quinases/metabolismo , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Pirimidinas/administração & dosagem , Pirimidinas/farmacologia
8.
Mol Cancer Ther ; 15(9): 2244-50, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27458141

RESUMO

mAbs can induce antibody-dependent cellular cytotoxicity (ADCC) via the innate immune system's ability to recognize mAb-coated cancer cells and activate immune effector cells. Lenalidomide is an immunomodulatory agent with the capacity to stimulate immune cell cytokine production and ADCC activity. This phase I trial evaluated the combination of cetuximab with lenalidomide for the treatment of advanced colorectal and head and neck squamous cell cancers (HNSCC). This trial included patients with advanced colorectal cancer or HNSCC. Treatment consisted of cetuximab 500 mg/m(2) i.v. every two weeks with lenalidomide given orally days 1-21 on a 28-day cycle. Three dose levels of lenalidomide were evaluated (15, 20, 25 mg). Correlative studies included measurement of ADCC, FcγRIIIA polymorphism genotyping, measurement of serum cytokine levels, and flow cytometric analysis of immune cell subtypes. Twenty-two patients were enrolled (19 colorectal cancer, 3 HNSCC). Fatigue was the only dose-limiting toxicity. One partial response was observed and 8 patients had stable disease at least 12 weeks. The recommended phase II dose is cetuximab 500 mg/m(2) with lenalidomide 25 mg daily, days 1-21. Correlative studies demonstrated a dose-dependent increase in natural killer cytotoxic activity with increasing doses of lenalidomide. Cetuximab and lenalidomide were well tolerated. There was a lenalidomide dose-dependent increase in ADCC with higher activity in patients enrolled in cohort 3 than those enrolled in cohorts 1/2. Although response was not a primary endpoint, there was evidence of antitumor activity for the combination therapy. Further investigation of lenalidomide as an immunomodulator in solid tumors is warranted. Mol Cancer Ther; 15(9); 2244-50. ©2016 AACR.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos/imunologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cetuximab/imunologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/imunologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/imunologia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cetuximab/administração & dosagem , Neoplasias Colorretais/patologia , Citocinas/metabolismo , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Lenalidomida , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Retratamento , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Talidomida/administração & dosagem , Talidomida/análogos & derivados , Resultado do Tratamento
9.
Cancer Immunol Res ; 4(4): 323-336, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26865456

RESUMO

Optimally effective antitumor therapies would not only activate immune effector cells but also engage them at the tumor. Folate conjugated to immunoglobulin (F-IgG) could direct innate immune cells with Fc receptors to folate receptor-expressing cancer cells. F-IgG bound to human KB and HeLa cells, as well as murine L1210JF, a folate receptor (FR)-overexpressing cancer cell line, as determined by flow cytometry. Recognition of F-IgG by natural killer (NK) cell Fc receptors led to phosphorylation of the ERK transcription factor and increased NK cell expression of CD69. Lysis of KB tumor cells by NK cells increased by about 5-fold after treatment with F-IgG, an effect synergistically enhanced by treatment with IL2, IL12, IL15, or IL21 (P< 0.001). F-IgG also enhanced the lysis of chronic lymphocytic leukemia cells by autologous NK cells. NK cells significantly increased production of IFNγ, MIP-1α, and RANTES in response to F-IgG-coated KB target cells in the presence of the NK cell-activating cytokine IL12, and these coculture supernatants induced significant T-cell chemotaxis (P< 0.001). F-IgG-coated targets also stimulated FcR-mediated monocyte effector functions. Studies in a murine leukemia model confirmed the intratumoral localization and antitumor activity of F-IgG, as well as enhancement of its effects by IL12 (P =0.05). The antitumor effect of this combination was dependent on NK cells and led to decreased tumor cell proliferation in vivo Thus, F-IgG can induce an immune response against FR-positive tumor cells that is mediated by NK cells and can be augmented by cytokine therapy.


Assuntos
Citocinas/metabolismo , Citotoxicidade Imunológica , Ácido Fólico/administração & dosagem , Imunoconjugados/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Animais , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Linhagem Celular Tumoral , Citotoxicidade Imunológica/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Receptor 1 de Folato/genética , Receptor 1 de Folato/metabolismo , Expressão Gênica , Humanos , Imunoglobulina G/imunologia , Imunomodulação , Interleucina-12/biossíntese , Ativação Linfocitária/imunologia , Camundongos , Monócitos/imunologia , Monócitos/metabolismo , Neoplasias/genética , Neoplasias/patologia , Carga Tumoral/imunologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
JAMA Oncol ; 1(1): 80-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26182309

RESUMO

IMPORTANCE: The Bruton tyrosine kinase (BTK) inhibitor ibrutinib is effective in patients with chronic lymphocytic leukemia (CLL). Reasons for discontinuing therapy with this drug and outcomes following discontinuation have not been evaluated outside of clinical trials with relatively short follow-up. OBJECTIVE: To determine features associated with discontinuation of ibrutinib therapy and outcomes. DESIGN, SETTING, AND PARTICIPANTS: A total of 308 patients participating in 4 sequential trials of ibrutinib at The Ohio State University Comprehensive Cancer Center were included. These clinical trials accrued patients included in this analysis from May 2010 until April 2014, and data were locked in June 2014. MAIN OUTCOMES AND MEASURES: Patients were evaluated for time to therapy discontinuation, reasons for discontinuation, and survival following discontinuation. For patients who discontinued therapy because of disease progression, targeted deep sequencing was performed in samples at baseline and time of relapse. RESULTS: With a median follow-up of 20 months, 232 patients remained on therapy, 31 had discontinued because of disease progression, and 45 had discontinued for other reasons. Disease progression includes Richter's transformation (RT) or progressive CLL. Richter's transformation appeared to occur early and CLL progressions later (cumulative incidence at 12 months, 4.5% [95% CI, 2.0%-7.0%] and 0.3% [95% CI, 0%-1.0%], respectively). Median survival following RT was 3.5 months (95% CI, 0.3-6.0 months) and 17.6 months (95% CI, 4.7 months-"not reached") following CLL progression. Sequencing on peripheral blood from 8 patients with RT revealed 2 with mutations in BTK, and a lymph node sample showed no mutations in BTK or PLCG2. Deep sequencing on 11 patients with CLL progression revealed BTK or PLCG2 mutations in all. These mutations were not identified before treatment in any patient. CONCLUSIONS AND RELEVANCE: This single-institution experience with ibrutinib confirms it to be an effective therapy and identifies, for the first time, baseline factors associated with ibrutinib therapy discontinuation. Outcomes data show poor prognosis after discontinuation, especially for those patients with RT. Finally, sequencing data confirm initial reports associating mutations in BTK and PLCG2 with progression and clearly show that CLL progressions are associated with these mutations, while RT is likely not. TRIAL REGISTRATIONS: clinicaltrials.gov Identifiers:NCT01105247, NCT01217749, NCT01589302, and NCT01578707.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis/uso terapêutico , Pirimidinas/uso terapêutico , Adenina/análogos & derivados , Adulto , Tirosina Quinase da Agamaglobulinemia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/antagonistas & inibidores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ensaios Clínicos como Assunto , Análise Mutacional de DNA/métodos , Progressão da Doença , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/mortalidade , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Mutação , Ohio , Fosfolipase C gama/genética , Piperidinas , Inibidores de Proteínas Quinases/efeitos adversos , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/metabolismo , Pirazóis/efeitos adversos , Pirimidinas/efeitos adversos , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Blood ; 123(8): 1207-13, 2014 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-24311722

RESUMO

Chronic lymphocytic leukemia (CLL) is characterized by constitutive activation of the B-cell receptor (BCR) signaling pathway, but variable responsiveness of the BCR to antigen ligation. Bruton's tyrosine kinase (BTK) shows constitutive activity in CLL and is the target of irreversible inhibition by ibrutinib, an orally bioavailable kinase inhibitor that has shown outstanding activity in CLL. Early clinical results in CLL with other reversible and irreversible BTK inhibitors have been less promising, however, raising the question of whether BTK kinase activity is an important target of ibrutinib and also in CLL. To determine the role of BTK in CLL, we used patient samples and the Eµ-TCL1 (TCL1) transgenic mouse model of CLL, which results in spontaneous leukemia development. Inhibition of BTK in primary human CLL cells by small interfering RNA promotes apoptosis. Inhibition of BTK kinase activity through either targeted genetic inactivation or ibrutinib in the TCL1 mouse significantly delays the development of CLL, demonstrating that BTK is a critical kinase for CLL development and expansion and thus an important target of ibrutinib. Collectively, our data confirm the importance of kinase-functional BTK in CLL.


Assuntos
Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/enzimologia , Proteínas Tirosina Quinases/metabolismo , Pirazóis/farmacologia , Pirimidinas/farmacologia , Adenina/análogos & derivados , Adulto , Tirosina Quinase da Agamaglobulinemia , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Modelos Animais de Doenças , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Piperidinas , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia
12.
Clin Cancer Res ; 19(9): 2406-19, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23515408

RESUMO

PURPOSE: The proteasome consists of chymotrypsin-like (CT-L), trypsin-like, and caspase-like subunits that cleave substrates preferentially by amino acid sequence. Proteasomes mediate degradation of regulatory proteins of the p53, Bcl-2, and nuclear factor-κB (NF-κB) families that are aberrantly active in chronic lymphocytic leukemia (CLL). CLL remains an incurable disease, and new treatments are especially needed in the relapsed/refractory setting. We therefore investigated the effects of the proteasome inhibitor carfilzomib (CFZ) in CLL cells. EXPERIMENTAL DESIGN: Tumor cells from CLL patients were assayed in vitro using immunoblotting, real-time polymerase chain reaction, and electrophoretic mobility shift assays. In addition, a p53 dominant-negative construct was generated in a human B-cell line. RESULTS: Unlike bortezomib, CFZ potently induces apoptosis in CLL patient cells in the presence of human serum. CLL cells have significantly lower basal CT-L activity compared to normal B and T cells, although activity is inhibited similarly in T cells versus CLL. Co-culture of CLL cells on stroma protected from CFZ-mediated cytotoxicity; however, PI3K inhibition significantly diminished this stromal protection. CFZ-mediated cytotoxicity in leukemic B cells is caspase-dependent and occurs irrespective of p53 status. In CLL cells, CFZ promotes atypical activation of NF-κB evidenced by loss of cytoplasmic IκBα, phosphorylation of IκBα, and increased p50/p65 DNA binding, without subsequent increases in canonical NF-κB target gene transcription. CONCLUSIONS: Together, these data provide new mechanistic insights into the activity of CFZ in CLL and support phase I investigation of CFZ in this disease.


Assuntos
Antineoplásicos/farmacologia , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , NF-kappa B/metabolismo , Oligopeptídeos/farmacologia , Inibidores de Proteassoma/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Apoptose , Linfócitos B/efeitos dos fármacos , Linfócitos B/enzimologia , Compostos de Benzil/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Inibidores de Caspase/farmacologia , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Óxidos N-Cíclicos , Avaliação Pré-Clínica de Medicamentos , Humanos , Hidrocarbonetos Fluorados/farmacologia , Indolizinas , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Complexo de Endopeptidases do Proteassoma/metabolismo , Subunidades Proteicas/antagonistas & inibidores , Subunidades Proteicas/metabolismo , Compostos de Piridínio/farmacologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/enzimologia , Células Tumorais Cultivadas/efeitos dos fármacos
13.
J Am Acad Nurse Pract ; 23(9): 464-72, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21899641

RESUMO

PURPOSE: This article reviews characteristics of amyotrophic lateral sclerosis (ALS) and appropriate timing of referrals by the nurse practitioner (NP). DATA SOURCES: Selected research and clinical articles. CONCLUSION: Management of patients with ALS by the NP requires anticipation of needed referrals based on symptom assessment and knowledge of the common timeline of ALS progression. Close collaboration with specialists such as neurologists, pulmonologists, and a palliative care team provides patients and families with much needed support and improves outcomes. IMPLICATIONS FOR PRACTICE: Anticipating and initiating appropriate and timely referrals for patients with ALS may improve quality of life for patients with this devastating condition.


Assuntos
Esclerose Lateral Amiotrófica/enfermagem , Medicina de Família e Comunidade/métodos , Profissionais de Enfermagem , Encaminhamento e Consulta , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/tratamento farmacológico , Progressão da Doença , Humanos , Cuidados Paliativos/métodos , Prognóstico , Fatores de Tempo
14.
AAPS J ; 13(3): 357-64, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21538216

RESUMO

Protein synthesis is a powerful therapeutic target in leukemias and other cancers, but few pharmacologically viable agents are available that affect this process directly. The plant-derived agent silvestrol specifically inhibits translation initiation by interfering with eIF4A/mRNA assembly with eIF4F. Silvestrol has potent in vitro and in vivo activity in multiple cancer models including acute lymphoblastic leukemia (ALL) and is under pre-clinical development by the US National Cancer Institute, but no information is available about potential mechanisms of resistance. In a separate report, we showed that intraperitoneal silvestrol is approximately 100% bioavailable systemically, although oral doses were only 1% bioavailable despite an apparent lack of metabolism. To explore mechanisms of silvestrol resistance and the possible role of efflux transporters in silvestrol disposition, we characterized multi-drug resistance transporter expression and function in a silvestrol-resistant ALL cell line generated via culture of the 697 ALL cell line in gradually increasing silvestrol concentrations. This resistant cell line, 697-R, shows significant upregulation of ABCB1 mRNA and P-glycoprotein (Pgp) as well as cross-resistance to known Pgp substrates vincristine and romidepsin. Furthermore, 697-R cells readily efflux the fluorescent Pgp substrate rhodamine 123. This effect is prevented by Pgp inhibitors verapamil and cyclosporin A, as well as siRNA to ABCB1, with concomitant re-sensitization to silvestrol. Together, these data indicate that silvestrol is a substrate of Pgp, a potential obstacle that must be considered in the development of silvestrol for oral delivery or targeting to tumors protected by Pgp overexpression.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/biossíntese , Resistencia a Medicamentos Antineoplásicos , Iniciação Traducional da Cadeia Peptídica/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Triterpenos/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Interpretação Estatística de Dados , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras , RNA Interferente Pequeno/farmacologia , Regulação para Cima
15.
PLoS One ; 5(6): e10941, 2010 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-20532179

RESUMO

BACKGROUND: While deacetylase (DAC) inhibitors show promise for the treatment of B-cell malignancies, those introduced to date are weak inhibitors of class I and II DACs or potent inhibitors of class I DAC only, and have shown suboptimal activity or unacceptable toxicities. We therefore investigated the novel DAC inhibitor AR-42 to determine its efficacy in B-cell malignancies. PRINCIPAL FINDINGS: In mantle cell lymphoma (JeKo-1), Burkitt's lymphoma (Raji), and acute lymphoblastic leukemia (697) cell lines, the 48-hr IC(50) (50% growth inhibitory concentration) of AR-42 is 0.61 microM or less. In chronic lymphocytic leukemia (CLL) patient cells, the 48-hr LC(50) (concentration lethal to 50%) of AR-42 is 0.76 microM. AR-42 produces dose- and time-dependent acetylation both of histones and tubulin, and induces caspase-dependent apoptosis that is not reduced in the presence of stromal cells. AR-42 also sensitizes CLL cells to TNF-Related Apoptosis Inducing Ligand (TRAIL), potentially through reduction of c-FLIP. AR-42 significantly reduced leukocyte counts and/or prolonged survival in three separate mouse models of B-cell malignancy without evidence of toxicity. CONCLUSIONS/SIGNIFICANCE: Together, these data demonstrate that AR-42 has in vitro and in vivo efficacy at tolerable doses. These results strongly support upcoming phase I testing of AR-42 in B-cell malignancies.


Assuntos
Linfoma de Burkitt/patologia , Inibidores de Histona Desacetilases/farmacologia , Linfoma de Célula do Manto/patologia , Fenilbutiratos/farmacologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Apoptose , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Humanos
16.
Br J Haematol ; 147(4): 507-14, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19747365

RESUMO

MGCD0103, an orally available class I histone deacetylase (HDAC) inhibitor, was examined for pre-clinical activity in chronic lymphocytic leukaemia (CLL). A phase II clinical trial was performed, starting at a dose of 85 mg/d, three times per week. Dose escalation to 110 mg or the addition of rituximab was permitted in patients without a response after two or more cycles. MGCD0103 demonstrated pre-clinical activity against CLL cells with a LC(50) (concentration lethal to 50%) of 0.23 micromol/l and increased acetylation of the HDAC class I specific target histone H3. Twenty-one patients received a median of two cycles of MGCD0103 (range, 0-12). All patients had previously received fludarabine, 33% were fludarabine refractory, and 71% had del(11q22.3) or del(17p13.1). No responses according to the National Cancer Institutes 1996 criteria were observed. Three patients received 110 mg and four patients received concomitant rituximab, with no improvement in response. Grade 3-4 toxicity consisted of infections, thrombocytopenia, anaemia, diarrhoea, and fatigue. HDAC inhibition was observed in six out of nine patients on day 8. Limited activity was observed with single agent MGCD0103 in high risk patients with CLL. Future investigations in CLL should focus on broad HDAC inhibition, combination strategies, and approaches to diminish constitutional symptoms associated with this class of drugs.


Assuntos
Antineoplásicos/uso terapêutico , Benzamidas/uso terapêutico , Inibidores de Histona Desacetilases/uso terapêutico , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Pirimidinas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzamidas/administração & dosagem , Benzamidas/efeitos adversos , Aberrações Cromossômicas , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Inibidores de Histona Desacetilases/administração & dosagem , Inibidores de Histona Desacetilases/efeitos adversos , Histona Desacetilases/metabolismo , Humanos , Leucemia Linfocítica Crônica de Células B/enzimologia , Leucemia Linfocítica Crônica de Células B/genética , Masculino , Pessoa de Meia-Idade , Pirimidinas/administração & dosagem , Pirimidinas/efeitos adversos , Rituximab , Resultado do Tratamento
17.
Proteomics ; 9(5): 1197-206, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19253275

RESUMO

The in vitro evaluation of histones and their PTMs has drawn substantial interest in the development of epigenetic therapies. The differential expression of histone isoforms may serve as a potential marker in the classification of diseases affected by chromatin abnormalities. In this study, protein profiling by LC and MS was used to explore differences in histone composition in primary chronic lymphocytic leukemia (CLL) cells. Extensive method validations were performed to determine the experimental variances that would impact histone relative abundance. The resulting data demonstrated that the proposed methodology was suitable for the analysis of histone profiles. In 4 normal individuals and 40 CLL patients, a significant decrease in the relative abundance of histone H2A variants (H2AFL and H2AFA/M*) was observed in primary CLL cells as compared to normal B cells. Protein identities were determined using high mass accuracy MS and shotgun proteomics.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Histonas/análise , Leucemia Linfocítica Crônica de Células B/genética , Espectrometria de Massas/métodos , Animais , Linfócitos B , Biomarcadores/análise , Bovinos , Regulação Neoplásica da Expressão Gênica , Histonas/genética , Humanos , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/metabolismo , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Reprodutibilidade dos Testes
18.
Blood ; 113(19): 4656-66, 2009 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-19190247

RESUMO

Therapeutic options for advanced B-cell acute lymphoblastic leukemia (ALL) and chronic lymphocytic leukemia (CLL) are limited. Available treatments can also deplete T lymphocytes, leaving patients at risk of life-threatening infections. In the National Cancer Institute cell line screen, the structurally unique natural product silvestrol produces an unusual pattern of cytotoxicity that suggests activity in leukemia and selectivity for B cells. We investigated silvestrol efficacy using primary human B-leukemia cells, established B-leukemia cell lines, and animal models. In CLL cells, silvestrol LC(50) (concentration lethal to 50%) is 6.9 nM at 72 hours. At this concentration, there is no difference in sensitivity of cells from patients with or without the del(17p13.1) abnormality. In isolated cells and whole blood, silvestrol is more cytotoxic toward B cells than T cells. Silvestrol causes early reduction in Mcl-1 expression due to translational inhibition with subsequent mitochondrial damage, as evidenced by reactive oxygen species generation and membrane depolarization. In vivo, silvestrol causes significant B-cell reduction in Emu-Tcl-1 transgenic mice and significantly extends survival of 697 xenograft severe combined immunodeficient (SCID) mice without discernible toxicity. These data indicate silvestrol has efficacy against B cells in vitro and in vivo and identify translational inhibition as a potential therapeutic target in B-cell leukemias.


Assuntos
Linfócitos B/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Triterpenos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linfócitos B/metabolismo , Western Blotting , Deleção Cromossômica , Cromossomos Humanos Par 17/genética , Feminino , Humanos , Técnicas In Vitro , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos SCID , Camundongos Transgênicos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteína de Sequência 1 de Leucemia de Células Mieloides , Leucemia-Linfoma Linfoblástico de Células Precursoras/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Transplante Heterólogo
19.
Blood ; 113(3): 535-7, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19008456

RESUMO

Myeloid cell leukemia-1 (Mcl-1) is an antiapoptotic member of the Bcl-2 protein family. Increased Mcl-1 expression is associated with failure to achieve remission after treatment with fludarabine and chlorambucil in patients with chronic lymphocytic leukemia (CLL). However, the influence of Mcl-1 expression has not been examined in CLL trials using chemoimmunotherapy. We investigated Mcl-1 protein expression prospectively as part of a phase 2 study evaluating the efficacy of pentostatin, cyclophosphamide, and rituximab in patients with untreated CLL. No significant difference by Mcl-1 expression was noted in pretreatment or response parameters. However, in patients with higher Mcl-1 expression, both minimal residual disease-negative status and progression-free survival was found to be significantly reduced (57% vs 19%, P = .01; 50.8 vs 18.7 months; P = .02; respectively). Mcl-1 expression may therefore be useful in predicting poor response to chemoimmunotherapy. These findings further support pursuing treatment strategies targeting this important antiapoptotic protein. (Because the trials described were conducted before the requirement to register them was implemented, they are not registered in a clinical trial database.).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biomarcadores Tumorais/análise , Leucemia Linfocítica Crônica de Células B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Murinos , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/mortalidade , Proteína de Sequência 1 de Leucemia de Células Mieloides , Pentostatina/administração & dosagem , Rituximab , Resultado do Tratamento
20.
Br J Nurs ; 17(8): 512-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18563024

RESUMO

Symptom control is an important part of maintaining a palliative patient's comfort and dignity, particularly in the end stages of their illness. Within the discipline of palliative care, the use of continuous subcutaneous syringe drivers is an important way of administering drugs at the end stages of a patient's illness to maintain symptom control. This study identified that ward staff had difficulty in obtaining the correct equipment, such as administration sets and Luer-lock syringes, leading to significant delays in patients being given drugs, affecting patient care and, when unable to obtain the correct equipment, the incorrect equipment was used. It was also identified that there was no consistent approach to the use or maintenance of syringe drivers, with a clear risk to patient safety. The study aim was to identify whether the introduction of a centralized storage system of set boxes containing all the relevant equipment would resolve these issues and improve patient care and safety. The audit showed that a centralized storage system enhanced practice by ensuring that there was a standardized approach to the initiation and care of syringe drivers, including equipment when used in the palliative care setting. The system also provided easy access to the correct equipment, reducing in the delay of commencing treatment, as well as the risk of any adverse events.


Assuntos
Bombas de Infusão , Injeções Subcutâneas , Seringas , Humanos , Cuidados Paliativos
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