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1.
Immunity ; 32(2): 240-52, 2010 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-20153221

RESUMO

Injury to the central nervous system initiates an uncontrolled inflammatory response that results in both tissue repair and destruction. Here, we showed that, in rodents and humans, injury to the spinal cord triggered surface expression of CD95 ligand (CD95L, FasL) on peripheral blood myeloid cells. CD95L stimulation of CD95 on these cells activated phosphoinositide 3-kinase (PI3K) and metalloproteinase-9 (MMP-9) via recruitment and activation of Syk kinase, ultimately leading to increased migration. Exclusive CD95L deletion in myeloid cells greatly decreased the number of neutrophils and macrophages infiltrating the injured spinal cord or the inflamed peritoneum after thioglycollate injection. Importantly, deletion of myeloid CD95L, but not of CD95 on neural cells, led to functional recovery of spinal injured animals. Our results indicate that CD95L acts on peripheral myeloid cells to induce tissue damage. Thus, neutralization of CD95L should be considered as a means to create a controlled beneficial inflammatory response.


Assuntos
Movimento Celular , Proteína Ligante Fas/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Mieloides/metabolismo , Peritonite/imunologia , Proteínas Tirosina Quinases/metabolismo , Animais , Células Cultivadas , Proteína Ligante Fas/genética , Proteína Ligante Fas/imunologia , Humanos , Inflamação , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/imunologia , Células Mieloides/patologia , Peritônio/imunologia , Peritônio/patologia , Peritonite/induzido quimicamente , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Medula Espinal/imunologia , Medula Espinal/patologia , Quinase Syk , Tioglicolatos/administração & dosagem
2.
Breast Cancer Res Treat ; 164(2): 359-369, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28439738

RESUMO

PURPOSE: The antimalarial drug artesunate (ART) is a promising candidate for cancer treatment as it displays anticancer effects in various models. While in short-term treatment of malaria, an excellent safety profile has been found for ART, the potential long-term treatment of cancer patients demands a phase I dose-finding clinical trial determining the daily ART dose which would be well tolerated as add-on therapy. METHODS: Patients with metastatic breast cancer were to receive either 100 or 150 or 200 mg oral ART daily as add-on to their guideline-based oncological therapy for a study period of four weeks with frequent clinical and laboratory monitoring until 4-8 weeks thereafter. According to the statistical design, recruitment was scheduled in groups of three patients in order not to miss a more than 33% frequency of dose-limiting adverse events (DL-AE) prior to dose escalation. RESULTS: Twenty-three patients were recruited, and all planned dose levels were applied. During the actual trial period of 4 ± 1 weeks, three patients experienced six DL-AEs altogether (leucopenia, neutropenia, asthenia, anemia) possibly related to ART (not exceeding 33% in any dose level). CONCLUSIONS: Up to 200 mg/d (2.2-3.9 mg/kg/d) oral ART were safe and well tolerated; therefore, 200 mg/d are recommended for phase II/III trials. Safety monitoring should include reticulocytes, NTproBNP, as well as audiological and neurological exploration.


Assuntos
Antineoplásicos Hormonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Artemisininas/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Antineoplásicos Hormonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Artemisininas/efeitos adversos , Artesunato , Esquema de Medicação , Feminino , Humanos , Dose Máxima Tolerável , Pessoa de Meia-Idade , Metástase Neoplásica , Estudos Prospectivos , Resultado do Tratamento
3.
Biom J ; 58(2): 416-27, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26711717

RESUMO

Reproducible research (RR) constitutes the idea that a publication should be accompanied by all relevant material to reproduce the results and findings of a scientific work. Hence, results can be verified and researchers are able to build upon these. Efforts of the Biometrical Journal over the last five years have increased the number of manuscripts which are reproducible by a factor of 4 to almost 50%. Yet, more than half of the code submission could not be executed in the initial review due to missing code, missing data or errors in the code. Careful checks of the submitted code as part of the reviewing process are essential to eliminate these issues and to foster RR. In this article, we reviewed n=56 recent submissions of code and data to identify common reproducibility issues. Based on these findings, guidelines for structuring code submission to the Biometrical Journal have been established to help authors. These guidelines should help researchers to implement RR in general. Together with the code reviews, this supports the mission of the Biometrical Journal in publishing highest quality, novel and relevant papers on statistical methods and their applications in life sciences. Source code and data to reproduce the presented data analyses are available as Supplementary Material on the journal's web page.


Assuntos
Biometria , Guias como Assunto , Publicações Periódicas como Assunto , Estatística como Assunto , Documentação , Reprodutibilidade dos Testes , Software
4.
BMC Cancer ; 15: 868, 2015 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-26547188

RESUMO

BACKGROUND: Definitive, percutaneous irradiation of the prostate and the pelvic lymph nodes in high-risk prostate cancer is the alternative to prostatectomy plus lymphadenectomy. To date, the role of whole pelvis radiotherapy (WPRT) has not been clarified especially taking into consideration the benefits of high conformal IMRT (intensity modulated radiotherapy) of complex-shaped target volumes. METHODS: From 2009 to 2012, 40 patients of high-risk prostate cancer with an increased risk of microscopic lymph node involvement were enrolled into this prospective phase II trial. Patients received at least two months of antihormonal treatment (AT) before radiotherapy continuing for at least 2 years. Helical IMRT (tomotherapy) of the pelvic lymph nodes (51.0 Gy) with a simultaneous integrated, moderate hypofractionated boost (single dose of 2.25 Gy) to the prostate (76.5 Gy) was performed in 34 fractions. PSA levels, prostate-related symptoms and quality of life were assessed at regular intervals for 24 months. RESULTS: Of the 40 patients enrolled, 38 finished the treatment as planned. Overall acute toxicity rates were low and no acute grade 3 or 4 gastrointestinal (GI) and genitourinary (GU) toxicity occurred. 21.6% of patients experienced acute grade 2 but no late grade ≥ 2 GI toxicity. Regarding GU side effects, results showed 48.6% acute grade 2 and 6.4% late grade 2 toxicity. After a median observation time of 23.4 months the PLATIN 1 trial can be considered as sufficiently safe meeting the prospectively defined aims of the trial. With 34/37 patients free of a PSA recurrence it shows promising efficacy. CONCLUSION: Tomotherapy of the pelvic lymph nodes with a simultaneous integrated boost to the prostate can be performed safely and without excessive toxicity. The combined irradiation of both prostate and pelvic lymph nodes seems to be as well tolerated as the irradiation of the prostate alone. TRIAL REGISTRATION: Trial Numbers: ARO 2009-05, ClinicalTrials.gov: NCT01903408.


Assuntos
Linfonodos/patologia , Pelve , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada , Idoso , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/mortalidade , Qualidade de Vida , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Resultado do Tratamento
5.
BMC Cancer ; 14: 20, 2014 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-24422782

RESUMO

BACKGROUND: Adjuvant and salvage radiotherapy of the prostate bed are established treatment options for prostate cancer. While the benefit of an additional radiotherapy of the pelvic lymph nodes is still under debate, the PLATIN 3 prospective phase II clinical trial was initiated to substantiate toxicity data on postoperative IMRT of the pelvic lymph nodes and the prostate bed. METHODS: From 2009 to 2011, 40 patients with high-risk prostate cancer after prostatectomy with pT3 R0/1 M0 or pT2 R1 M0 or a PSA recurrence and either > 20% risk of lymph node involvement and inadequate lymphadenectomy or pN + were enrolled. Patients received two months of antihormonal treatment (AT) before radiotherapy. AT continuation was mandatory during radiotherapy and was recommended for another two years. IMRT of the pelvic lymph nodes (51.0 Gy) with a simultaneous integrated boost to the prostate bed (68.0 Gy) was performed in 34 fractions. PSA level, prostate-related symptoms and quality of life were assessed at regular intervals for 24 months. RESULTS: Of the 40 patients enrolled, 39 finished treatment as planned. Overall acute toxicity rates were low and no acute grade 3/4 toxicity occurred. Only 22.5% of patients experienced acute grade 2 gastrointestinal (GI) and genitourinary (GU) toxicity. During follow-up, 10.0% late grade 2 GI and 5.0% late grade 2 GU toxicity occurred, and one patient developed late grade 3 proctitis and enteritis. After a median observation time of 24 months the PLATIN 3 trial has shown in 97.5% of all patients sufficient safety and thus met its prospectively defined aims. After a median of 24 months, 34/38 patients were free of a PSA recurrence. CONCLUSIONS: Postoperative whole-pelvis IMRT with an integrated boost to the prostate bed can be performed safely and without excessive toxicity.


Assuntos
Linfonodos/efeitos da radiação , Irradiação Linfática/métodos , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada , Idoso , Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Alemanha , Humanos , Calicreínas/sangue , Linfonodos/patologia , Irradiação Linfática/efeitos adversos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Pelve , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
6.
BMC Cancer ; 14: 202, 2014 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24641841

RESUMO

BACKGROUND: Due to physical characteristics, ions like protons or carbon ions can administer the dose to the target volume more efficiently than photons since the dose can be lowered at the surrounding normal tissue. Radiation biological considerations are based on the assumption that the α/ß value for prostate cancer cells is 1.5 Gy, so that a biologically more effective dose could be administered due to hypofractionation without increasing risks of late effects of bladder (α/ß = 4.0) and rectum (α/ß = 3.9). METHODS/DESIGN: The IPI study is a prospective randomized phase II study exploring the safety and feasibility of primary hypofractionated irradiation of the prostate with protons and carbon ions in a raster scan technique. The study is designed to enroll 92 patients with localized prostate cancer. Primary aim is the assessment of the safety and feasibility of the study treatment on the basis of incidence grade III and IV NCI-CTC-AE (v. 4.02) toxicity and/or the dropout of the patient from the planned therapy due to any reason. Secondary endpoints are PSA-progression free survival (PSA-PFS), overall survival (OS) and quality-of-life (QoL). DISCUSSION: This pilot study aims at the evaluation of the safety and feasibility of hypofractionated irradiation of the prostate with protons and carbon ions in prostate cancer patients in an active beam technique. Additionally, the safety results will be compared with Japanese results recently published for carbon ion irradiation. Due to the missing data of protons in this hypofractionated scheme, an in depth evaluation of the toxicity will be created to gain basic data for a following comparison study with carbon ion irradiation. TRIAL REGISTRATION: Clinical Trial Identifier: NCT01641185 (clinicaltrials.gov).


Assuntos
Radioterapia com Íons Pesados/efeitos adversos , Próstata/efeitos da radiação , Neoplasias da Próstata/radioterapia , Terapia com Prótons/efeitos adversos , Intervalo Livre de Doença , Humanos , Masculino , Estudos Prospectivos , Próstata/patologia , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologia , Qualidade de Vida , Resultado do Tratamento
7.
Toxicol Appl Pharmacol ; 270(3): 218-29, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22306862

RESUMO

Melamine can be present at low levels in food and feed mostly from its legal use as a food contact material in laminates and plastics, as a trace contaminant in nitrogen supplements used in animal feeds, and as a metabolite of the pesticide cyromazine. The mechanism of toxicity of melamine involves dose-dependent formation of crystals with either endogenous uric acid or a structural analogue of melamine, cyanuric acid, in renal tubules resulting in potential acute kidney failure. Co-exposure to melamine and cyanuric acid in livestock, fish, pets and laboratory animals shows higher toxicity compared with melamine or cyanuric acid alone. Evidence for crystal formation between melamine and other structural analogs i.e. ammelide and ammeline is limited. Illegal pet food adulterations with melamine and cyanuric acid and adulteration of milk with melamine resulted in melamine-cyanuric acid crystals, kidney damage and deaths of cats and dogs and melamine-uric acid stones, hospitalisation and deaths of children in China respectively. Following these incidents, the tolerable daily intake for melamine was re-evaluated by the U.S. Food and Drug Administration, the World Health Organisation, and the Scientific Panel on Contaminants in the Food Chain of the European Food Safety Authority (EFSA). This review provides an overview of toxicology, the adulteration incidents and risk assessments for melamine and its structural analogues. Particular focus is given to the recent EFSA risk assessment addressing impacts on animal and human health of background levels of melamine and structural analogues in animal feed. Recent research and future directions are discussed.


Assuntos
Ração Animal/análise , Contaminação de Alimentos , Fraude , Triazinas/análise , Ração Animal/efeitos adversos , Animais , Contaminação de Alimentos/prevenção & controle , Fraude/prevenção & controle , Humanos , Medição de Risco/normas , Medição de Risco/tendências , Triazinas/efeitos adversos
8.
Acta Oncol ; 52(1): 147-52, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22686472

RESUMO

UNLABELLED: Re-irradiation using high-precision radiation techniques has been established within the clinical routine for patients with recurrent gliomas. In the present work, we developed a practical prognostic score to predict survival outcome after re-irradiation. PATIENTS AND METHODS: Fractionated stereotactic radiotherapy (FSRT) was applied in 233 patients. Primary histology included glioblastoma (n = 89; 38%), WHO Grade III gliomas (n = 52; 22%) and low-grade glioma (n = 92; 40%). FSRT was applied with a median dose of 36 Gy in 2 Gy single fractions. We evaluated survival after re-irradiation as well as progression-free survival after re-irradiation; prognostic factors analyzed included age, tumor volume at re-irradiation, histology, time between initial radiotherapy and re-irradiation, age and Karnofsky Performance Score. RESULTS: Median survival after FSRT was 8 months for glioblastoma, 20 months for anaplastic gliomas, and 24 months for recurrent low-grade patients. The strongest prognostic factors significantly impacting survival after re-irradiation were histology (p < 0.0001) and age (< 50 vs. ≥ 50, p < 0.0001) at diagnosis and the time between initial radiotherapy and re-irradiation ≤ 12 vs. > 12 months (p < 0.0001). We generated a four-class prognostic score to distinguish patients with excellent (0 points), good (1 point), moderate (2 points) and poor (3-4 points) survival after re-irradiation. The difference in outcome was highly significant (p < 0.0001). CONCLUSION: We generated a practical prognostic score index based on three clinically relevant factors to predict the benefit of patients from re-irradiation. This score index can be helpful in patient counseling, and for the design of further clinical trials. However, individual treatment decisions may include other patient-related factors not directly influencing outcome.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Glioma/radioterapia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/radioterapia , Adolescente , Adulto , Fatores Etários , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Criança , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Retratamento , Tempo para o Tratamento , Adulto Jovem
9.
Int J Cancer ; 131(12): 2920-8, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22473764

RESUMO

ATP-binding cassette (ABC) transporter expression and genetic heterogeneity have been implicated in response to anticancer therapy. This study characterized genetic variability of the ABCB1 (also known as MDR1), ABCC2 (MRP2) and ABCG2 (BCRP) genes, which are key players in the metabolism of many chemotherapeutic agents including those used in the treatment of lung cancer. We genotyped 53 polymorphisms in the candidate genes in genomic DNA samples of 171 cases of small cell lung carcinoma (SCLC) and 206 cases of non-small cell lung carcinoma (NSCLC), and studied their impact on early response to chemotherapy, progression-free survival and overall survival. SNP rs717620 in ABCC2 was moderately associated with a poor response to chemotherapy but strongly with shorter progression-free survival and overall survival in SCLC but not NSCLC patients, indicating that ABCC2 genetic variation is an important factor in SCLC survival after chemotherapy.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/genética , Antineoplásicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas de Neoplasias/genética , Polimorfismo Genético , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/patologia , Feminino , Haplótipos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Prognóstico
10.
BMC Cancer ; 12: 504, 2012 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-23114055

RESUMO

BACKGROUND: While evidence on safety and efficacy of primary hypofractionated radiotherapy in prostate cancer is accumulating, data on postoperative hypofractionated treatment of the prostate bed and of the pelvic lymph nodes is still scarce. This phase II trial was initiated to investigate safety and feasibility of hypofractionated treatment of the prostate bed alone or with the pelvic lymph nodes. METHODS/DESIGN: A total of 80 prostate cancer patients with the indication for adjuvant radiotherapy will be enrolled, where 40 patients with a low risk of lymph node involvement (arm 1) and another 40 patients with a high risk of lymph node involvement (arm 2) will each receive 54 Gy in 18 fractions to the prostate bed. Arm 2 will be given 45 Gy to the pelvic lymph nodes additionally. Helical Tomotherapy and daily image guidance will be used. DISCUSSION: This trial was initiated to substantiate data on hypofractionated treatment of the prostate bed and generate first data on adjuvant hypofractionated radiotherapy of the pelvic lymph nodes. TRIAL REGISTRATION: ClinicalTrials.gov; NCT01620710.


Assuntos
Linfonodos/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase II como Assunto/métodos , Antagonistas de Hormônios/uso terapêutico , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Prostatectomia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/cirurgia , Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Análise de Sobrevida
11.
BMC Cancer ; 12: 287, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22788989

RESUMO

BACKGROUND: Local control rates in patients with retroperitoneal soft tissue sarcoma (RSTS) remain disappointing even after gross total resection, mainly because wide margins are not achievable in the majority of patients. In contrast to extremity sarcoma, postoperative radiation therapy (RT) has shown limited efficacy due to its limitations in achievable dose and coverage. Although Intraoperative Radiation Therapy (IORT) has been introduced in some centers to overcome the dose limitations and resulted in increased outcome, local failure rates are still high even if considerable treatment related toxicity is accepted. As postoperative administration of RT has some general disadvantages, neoadjuvant approaches could offer benefits in terms of dose escalation, target coverage and reduction of toxicity, especially if highly conformal techniques like intensity-modulated radiation therapy (IMRT) are considered. METHODS/DESIGN: The trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant dose-escalated IMRT (50-56 Gy) followed by surgery and IORT (10-12 Gy) in patients with at least marginally resectable RSTS. The primary objective is the local control rate after five years. Secondary endpoints are progression-free and overall survival, acute and late toxicity, surgical resectability and patterns of failure. The aim of accrual is 37 patients in the per-protocol population. DISCUSSION: The present study evaluates combined neoadjuvant dose-escalated IMRT followed by surgery and IORT concerning its value for improved local control without markedly increased toxicity. TRIAL REGISTRATION: NCT01566123.


Assuntos
Neoplasias Retroperitoneais/radioterapia , Neoplasias Retroperitoneais/cirurgia , Sarcoma/radioterapia , Sarcoma/cirurgia , Ensaios Clínicos Fase I como Assunto/métodos , Ensaios Clínicos Fase II como Assunto/métodos , Humanos , Cuidados Intraoperatórios/métodos , Terapia Neoadjuvante , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia Adjuvante/métodos , Radioterapia de Intensidade Modulada/métodos
12.
Stat Med ; 31(11-12): 1303-5, 2012 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21948351

RESUMO

International regulatory guidelines require that a 'qualified statistician' takes responsibility for the statistical aspects of a clinical trial used for drug licensing. No consensus on what constitutes a 'qualified statistician' appears to have been developed so far. The International Society for Clinical Biostatistics is issuing this reflection paper in order to stimulate a discussion on the concept.


Assuntos
Ensaios Clínicos como Assunto/legislação & jurisprudência , Ensaios Clínicos como Assunto/estatística & dados numéricos , Pesquisadores , Bioestatística , Humanos , Licenciamento/normas , Licenciamento/estatística & dados numéricos , Guias de Prática Clínica como Assunto , Estatística como Assunto/educação
13.
Mutat Res ; 744(1): 36-41, 2012 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-22178130

RESUMO

Validation activities of the BALB/c 3T3 cell transformation assay (CTA) - a test method used for the assessment of the carcinogenic potential of compounds - have revealed the need for statistical analysis tailored to specific features of BALB/c 3T3 CTA data. Whereas a standard statistical approach for the Syrian hamster embryo (SHE) CTA was considered sufficient, an international expert group was gathered by the European Centre for the Validation of Alternative Methods (ECVAM) to review commonly applied statistical approaches for BALB/c 3T3 CTA. As it was concluded that none of the commonly applied approaches is entirely appropriate, two novel statistical approaches were found to be recommended for the evaluation of BALB/c 3T3 CTA data accounting for possible non-monotone concentration-response relationship and variance heterogeneity: a negative binomial generalised linear model with William's-type downturn-protected trend tests and a normalisation of the data by a specific transformation allowing for application of a general linear model that estimates effects assuming a normal distribution with William's-type protected tests. Both approaches are described in this article and their performance and the quality of the results they generate is demonstrated using exemplary data. Our work confirmed that both approaches are suitable for the statistical analysis of BALB/c 3T3 CTA data and that each of them is superior to commonly used methods. Furthermore, a procedure dichotomising data into negatives and positives is proposed which allows re-testing in cases where inconclusive data are encountered. The scripts of the statistical evaluation programs written in R - a freely available statistical software - are appended including exemplary outputs (Appendix A).


Assuntos
Células 3T3 BALB , Testes de Carcinogenicidade/métodos , Transformação Celular Neoplásica , Modelos Estatísticos , Alternativas aos Testes com Animais/métodos , Animais , Carcinógenos/toxicidade , Camundongos , Projetos de Pesquisa
14.
J Biopharm Stat ; 22(2): 294-311, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22251175

RESUMO

For rare diseases, standard treatments are often not available and essential study parameters are difficult or impossible to obtain. Therefore, designs of clinical trials for these diseases are often based on little information. Adaptive designs allow such trials to be started and to gain information during the study. Motivated by a trial for a rare subtype of renal-cell carcinoma, we present a two-stage adaptive design for right-censored time-to-event data and a two-sided test. After the first stage, one can stop for futility or continue with reestimated sample size. The properties of such designs are analyzed by simulation studies.


Assuntos
Ensaios Clínicos Fase II como Assunto/estatística & dados numéricos , Doenças Raras/tratamento farmacológico , Doenças Raras/mortalidade , Projetos de Pesquisa/estatística & dados numéricos , Algoritmos , Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/mortalidade , Ensaios Clínicos Fase II como Assunto/métodos , Simulação por Computador , Interpretação Estatística de Dados , Humanos , Indóis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/mortalidade , Modelos de Riscos Proporcionais , Pirróis/uso terapêutico , Tamanho da Amostra , Sirolimo/análogos & derivados , Sirolimo/uso terapêutico , Sunitinibe , Sobrevida
15.
EFSA J ; 20(10): e07584, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36304832

RESUMO

The Scientific Committee (SC) reconfirms that the benchmark dose (BMD) approach is a scientifically more advanced method compared to the no-observed-adverse-effect-level (NOAEL) approach for deriving a Reference Point (RP). The major change compared to the previous Guidance (EFSA SC, 2017) concerns the Section 2.5, in which a change from the frequentist to the Bayesian paradigm is recommended. In the former, uncertainty about the unknown parameters is measured by confidence and significance levels, interpreted and calibrated under hypothetical repetition, while probability distributions are attached to the unknown parameters in the Bayesian approach, and the notion of probability is extended to reflect uncertainty of knowledge. In addition, the Bayesian approach can mimic a learning process and reflects the accumulation of knowledge over time. Model averaging is again recommended as the preferred method for estimating the BMD and calculating its credible interval. The set of default models to be used for BMD analysis has been reviewed and amended so that there is now a single set of models for quantal and continuous data. The flow chart guiding the reader step-by-step when performing a BMD analysis has also been updated, and a chapter comparing the frequentist to the Bayesian paradigm inserted. Also, when using Bayesian BMD modelling, the lower bound (BMDL) is to be considered as potential RP, and the upper bound (BMDU) is needed for establishing the BMDU/BMDL ratio reflecting the uncertainty in the BMD estimate. This updated guidance does not call for a general re-evaluation of previous assessments where the NOAEL approach or the BMD approach as described in the 2009 or 2017 Guidance was used, in particular when the exposure is clearly lower (e.g. more than one order of magnitude) than the health-based guidance value. Finally, the SC firmly reiterates to reconsider test guidelines given the wide application of the BMD approach.

16.
BMC Cancer ; 11: 67, 2011 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-21314962

RESUMO

BACKGROUND: Treatment options for patients with advanced hepatocellular carcinoma (HCC) are often limited. In most cases, they are not amenable to local therapies including surgery or radiofrequency ablation. The multi-kinase inhibitor sorafenib has shown to increase overall survival in this patient group for about 3 months.Radiation therapy is a treatment alternative, however, high local doses are required for long-term local control. However, due to the relatively low radiation tolerance of liver normal tissue, even using stereotactic techniques, delivery of sufficient doses for successful local tumor control has not be achieved to date.Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 2 and 3 depending on the HCC cell line as well as the endpoint analyzed.Japanese Data on the evaluation of carbon ion radiation therapy showed promising results for patients with HCC. METHODS/DESIGN: In the current Phase I-PROMETHEUS-01-Study, carbon ion radiotherapy will be evaluated for patients with advanced HCC. The study will be performed as a dose-escalation study evaluating the optimal carbon ion dose with respect to toxicity and tumor control.Primary endpoint is toxicity, secondary endpoint is progression-free survival and response. DISCUSSION: The Prometheus-01 trial ist the first trial evaluating carbon ion radiotherapy delivered by intensity-modulated rasterscanning for the treatment of HCC. Within this Phase I dose escalation study, the optimal dose of carbon ion radiotherapy will be determined. TRIAL REGISTRATION: NCT 01167374.


Assuntos
Carbono/uso terapêutico , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Íons/uso terapêutico , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Adulto Jovem
17.
BMC Cancer ; 11: 419, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-21961577

RESUMO

BACKGROUND: Insufficient migration and activation of tumor specific effector T cells in the tumor is one of the main reasons for inadequate host anti-tumor immune response. External radiation seems to induce inflammation and activate the immune response. This phase I/II clinical trial aims to evaluate whether low dose single fraction radiotherapy can improve T cell associated antitumor immune response in patients with colorectal liver metastases. METHODS/DESIGN: This is an investigator-initiated, prospective randomised, 4-armed, controlled Phase I/II trial. Patients undergoing elective hepatic resection due to colorectal cancer liver metastasis will be enrolled in the study. Patients will receive 0 Gy, 0.5 Gy, 2 Gy or 5 Gy radiation targeted to their liver metastasis. Radiation will be applied by external beam radiotherapy using a 6 MV linear accelerator (Linac) with intensity modulated radiotherapy (IMRT) technique two days prior to surgical resection. All patients admitted to the Department of General-, Visceral-, and Transplantion Surgery, University of Heidelberg for elective hepatic resection are consecutively screened for eligibility into this trial, and written informed consent is obtained before inclusion. The primary objective is to assess the effect of active local external beam radiation dose on, tumor infiltrating T cells as a surrogate parameter for antitumor activity. Secondary objectives include radiogenic treatment toxicity, postoperative morbidity and mortality, local tumor control and recurrence patterns, survival and quality of life. Furthermore, frequencies of systemic tumor reactive T cells in blood and bone marrow will be correlated with clinical outcome. DISCUSSION: This is a randomized controlled patient blinded trial to assess the safety and efficiency of low dose radiotherapy on metastasis infiltrating T cells and thus potentially enhance the antitumor immune response. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01191632.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Colorretais/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Linfócitos do Interstício Tumoral/efeitos da radiação , Idoso , Neoplasias Colorretais/imunologia , Humanos , Neoplasias Hepáticas/imunologia , Linfócitos do Interstício Tumoral/imunologia , Pessoa de Meia-Idade , Dosagem Radioterapêutica
18.
J Pathol ; 220(5): 551-61, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20077528

RESUMO

Endometrial carcinomas (ECs) are classified into type 1 (less aggressive) and type 2 (aggressive) tumours that differ in genetic alterations. So far, reliable immunohistochemical markers that can identify patients with high risk for recurrence are rare. We have defined the expression of L1 cell adhesion molecule (L1CAM), a biomarker previously identified for EC, and compared its expression to oestrogen receptor (ER)/progesterone receptor (PR) and E-cadherin. We found that L1CAM was absent in normal endometrium and the vast majority of endometrioid ECs (type 1) but was strongly expressed in serous and clear-cell ECs, considered as type 2. 78/272 cases were identified as L1CAM-positive endometrioid ECs that were correlated with a poor prognosis. Strikingly, we observed an inverse relationship between L1CAM and ER/PR/E-cadherin expression in all ECs. In mixed ECs, composed of endometrioid (L1CAM(-) ER/PR(+) E-cadherin(+)) and clear-cell/serous (L1CAM(+) ER/PR(-) E-cadherin(-)), both phenotypes were co-expressed. In some of these cases L1CAM was up-regulated at the leading edge of the tumour, where ER/PR and E-cadherin expression were selectively lost. In EC cell lines treated with the epithelial-mesenchymal transition (EMT) inducer TGFbeta1, L1CAM and vimentin were strongly up-regulated, while E-cadherin expression was reduced. The treatment also resulted in an increased expression of the EMT transcription factor Slug and an enhanced cell invasion. Depletion of Slug by siRNA knockdown prevented both L1CAM up-regulation and enhanced cell invasion. According to our analysis, we suggest that L1CAM is a novel marker for EMT in ECs and that L1CAM-typing could identify endometrioid ECs that have type 2-like features and are at high risk for recurrence.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias do Endométrio/metabolismo , Proteínas de Neoplasias/metabolismo , Molécula L1 de Adesão de Célula Nervosa/biossíntese , Regulação para Cima , Biomarcadores Tumorais/genética , Caderinas/metabolismo , Neoplasias do Endométrio/patologia , Endométrio/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Técnicas Imunoenzimáticas , Invasividade Neoplásica/fisiopatologia , Molécula L1 de Adesão de Célula Nervosa/genética , Prognóstico , RNA Neoplásico/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
19.
Nat Med ; 10(4): 389-95, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15004554

RESUMO

The clinical outcome of spinal cord injury (SCI) depends in part on the extent of secondary damage, to which apoptosis contributes. The CD95 and tumor necrosis factor (TNF) ligand/receptor systems play an essential role in various apoptotic mechanisms. To determine the involvement of these ligands in SCI-induced damage, we neutralized the activity of CD95 ligand (CD95L) and/or TNF in spinal cord-injured mice. Therapeutic neutralization of CD95L, but not of TNF, significantly decreased apoptotic cell death after SCI. Mice treated with CD95L-specific antibodies were capable of initiating active hind-limb movements several weeks after injury. The improvement in locomotor performance was mirrored by an increase in regenerating fibers and upregulation of growth-associated protein-43 (GAP-43). Thus, neutralization of CD95L promoted axonal regeneration and functional improvement in injured adult animals. This therapeutic strategy may constitute a potent future treatment for human spinal injury.


Assuntos
Axônios/fisiologia , Glicoproteínas de Membrana/antagonistas & inibidores , Regeneração , Traumatismos da Medula Espinal/fisiopatologia , Animais , Sobrevivência Celular , Proteína Ligante Fas , Camundongos , Neurônios/citologia , Testes de Neutralização , Oligodendroglia/citologia , Traumatismos da Medula Espinal/patologia
20.
Lab Invest ; 90(10): 1482-91, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20479716

RESUMO

Interferons (IFNs) are expressed by many cell types and play a pivotal role in the generation of immune responses against viral infections. IFN-κ, a novel type I IFN, displays a tight tropism for keratinocytes and specific lymphoid populations and exhibits functional similarities with other type I IFNs. The human papillomavirus (HPV), the etiological agent for cervical cancer, infects keratinocytes of the uterine cervix and has been shown to directly inhibit the IFN pathway. We evaluated IFN-κ, -ß, and -γ gene expression in HPV-negative normal and HPV-positive pre-malignant and malignant ex vivo cervical tissue covering the entire spectrum of cervical disease. Quantitative real-time polymerase chain reaction and methods previously optimized for detecting low-expressing genes in cervical tissue were used. In contrast to IFN-ß and -γ, IFN-κ mRNA prevalence and levels were unexpectedly higher in diseased compared with normal whole cervical tissue with highest levels observed in invasive carcinoma tissue. Strikingly, laser capture microdissection revealed an absence of IFN-κ mRNA in diseased epithelium, whereas stromal IFN-κ was found exclusively in diseased tissue. IFN-γ and IFN-ß were likewise found to be upregulated in diseased cervical stroma. Immunofluorescence supports the involvement of monocytes and dendritic cells in the stromal induction of IFNs in diseased tissue. Further, using three-dimensional raft cultures in which the viral life cycle can be mimicked, human keratinocytes transfected with full-length HPV16 displayed a significant decrease in IFN-κ mRNA compared with non-transfected human keratinocytes. Altogether, these findings show that IFN-κ is down-regulated in cervical keratinocytes harboring HPV, which may be a contributing factor in the progression of a cervical lesion.


Assuntos
Colo do Útero/metabolismo , Interferon Tipo I/metabolismo , Queratinócitos/metabolismo , Papillomaviridae , Infecções por Papillomavirus/metabolismo , Neoplasias do Colo do Útero/metabolismo , Colo do Útero/patologia , Colo do Útero/virologia , Regulação para Baixo , Feminino , Humanos , Interferon beta/metabolismo , Interferon gama/metabolismo , Queratinócitos/patologia , Queratinócitos/virologia , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia
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