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1.
Immunity ; 32(2): 240-52, 2010 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-20153221

RESUMEN

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.


Asunto(s)
Movimiento Celular , Proteína Ligando Fas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Células Mieloides/metabolismo , Peritonitis/inmunología , Proteínas Tirosina Quinasas/metabolismo , Animales , Células Cultivadas , Proteína Ligando Fas/genética , Proteína Ligando Fas/inmunología , Humanos , Inflamación , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Mieloides/inmunología , Células Mieloides/patología , Peritoneo/inmunología , Peritoneo/patología , Peritonitis/inducido químicamente , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Médula Espinal/inmunología , Médula Espinal/patología , Quinasa Syk , Tioglicolatos/administración & dosificación
2.
Breast Cancer Res Treat ; 164(2): 359-369, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28439738

RESUMEN

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.


Asunto(s)
Antineoplásicos Hormonales/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Artemisininas/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Adulto , Anciano , Antineoplásicos Hormonales/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Artemisininas/efectos adversos , Artesunato , Esquema de Medicación , Femenino , Humanos , Dosis Máxima Tolerada , Persona de Mediana Edad , Metástasis de la Neoplasia , Estudios Prospectivos , Resultado del Tratamiento
3.
Biom J ; 58(2): 416-27, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26711717

RESUMEN

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.


Asunto(s)
Biometría , Guías como Asunto , Publicaciones Periódicas como Asunto , Estadística como Asunto , Documentación , Reproducibilidad de los Resultados , Programas Informáticos
4.
BMC Cancer ; 15: 868, 2015 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-26547188

RESUMEN

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.


Asunto(s)
Ganglios Linfáticos/patología , Pelvis , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada , Anciano , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/mortalidad , Calidad de Vida , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Resultado del Tratamiento
5.
BMC Cancer ; 14: 20, 2014 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-24422782

RESUMEN

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.


Asunto(s)
Ganglios Linfáticos/efectos de la radiación , Irradiación Linfática/métodos , Neoplasias de la Próstata/radioterapia , Radioterapia de Intensidad Modulada , Anciano , Antagonistas de Andrógenos/uso terapéutico , Antineoplásicos Hormonales/uso terapéutico , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Alemania , Humanos , Calicreínas/sangre , Ganglios Linfáticos/patología , Irradiación Linfática/efectos adversos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Pelvis , Estudios Prospectivos , Antígeno Prostático Específico/sangre , Prostatectomía , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/efectos adversos , Factores de Tiempo , Resultado del Tratamiento
6.
BMC Cancer ; 14: 202, 2014 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-24641841

RESUMEN

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).


Asunto(s)
Radioterapia de Iones Pesados/efectos adversos , Próstata/efectos de la radiación , Neoplasias de la Próstata/radioterapia , Terapia de Protones/efectos adversos , Supervivencia sin Enfermedad , Humanos , Masculino , Estudios Prospectivos , Próstata/patología , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/patología , Calidad de Vida , Resultado del Tratamiento
7.
Toxicol Appl Pharmacol ; 270(3): 218-29, 2013 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22306862

RESUMEN

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.


Asunto(s)
Alimentación Animal/análisis , Contaminación de Alimentos , Fraude , Triazinas/análisis , Alimentación Animal/efectos adversos , Animales , Contaminación de Alimentos/prevención & control , Fraude/prevención & control , Humanos , Medición de Riesgo/normas , Medición de Riesgo/tendencias , Triazinas/efectos adversos
8.
Acta Oncol ; 52(1): 147-52, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22686472

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Glioma/radioterapia , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/radioterapia , Adolescente , Adulto , Factores de Edad , Anciano , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Niño , Supervivencia sin Enfermedad , Fraccionamiento de la Dosis de Radiación , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Glioma/mortalidad , Glioma/patología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Retratamiento , Tiempo de Tratamiento , Adulto Joven
9.
Int J Cancer ; 131(12): 2920-8, 2012 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-22473764

RESUMEN

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.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/genética , Antineoplásicos/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas de Neoplasias/genética , Polimorfismo Genético , Subfamilia B de Transportador de Casetes de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/patología , Femenino , Haplotipos , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Pronóstico
10.
BMC Cancer ; 12: 504, 2012 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-23114055

RESUMEN

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.


Asunto(s)
Ganglios Linfáticos/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Ensayos Clínicos Fase II como Asunto/métodos , Antagonistas de Hormonas/uso terapéutico , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prostatectomía , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Radioterapia Asistida por Computador , Radioterapia de Intensidad Modulada , Análisis de Supervivencia
11.
BMC Cancer ; 12: 287, 2012 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-22788989

RESUMEN

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.


Asunto(s)
Neoplasias Retroperitoneales/radioterapia , Neoplasias Retroperitoneales/cirugía , Sarcoma/radioterapia , Sarcoma/cirugía , Ensayos Clínicos Fase I como Asunto/métodos , Ensayos Clínicos Fase II como Asunto/métodos , Humanos , Cuidados Intraoperatorios/métodos , Terapia Neoadyuvante , Estudios Prospectivos , Dosificación Radioterapéutica , Radioterapia Adyuvante/métodos , Radioterapia de Intensidad Modulada/métodos
12.
Stat Med ; 31(11-12): 1303-5, 2012 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-21948351

RESUMEN

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.


Asunto(s)
Ensayos Clínicos como Asunto/legislación & jurisprudencia , Ensayos Clínicos como Asunto/estadística & datos numéricos , Investigadores , Bioestadística , Humanos , Concesión de Licencias/normas , Concesión de Licencias/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Estadística como Asunto/educación
13.
Mutat Res ; 744(1): 36-41, 2012 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-22178130

RESUMEN

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).


Asunto(s)
Células 3T3 BALB , Pruebas de Carcinogenicidad/métodos , Transformación Celular Neoplásica , Modelos Estadísticos , Alternativas a las Pruebas en Animales/métodos , Animales , Carcinógenos/toxicidad , Ratones , Proyectos de Investigación
14.
J Biopharm Stat ; 22(2): 294-311, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22251175

RESUMEN

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.


Asunto(s)
Ensayos Clínicos Fase II como Asunto/estadística & datos numéricos , Enfermedades Raras/tratamiento farmacológico , Enfermedades Raras/mortalidad , Proyectos de Investigación/estadística & datos numéricos , Algoritmos , Antineoplásicos/uso terapéutico , Carcinoma de Células Renales/tratamiento farmacológico , Carcinoma de Células Renales/mortalidad , Ensayos Clínicos Fase II como Asunto/métodos , Simulación por Computador , Interpretación Estadística de Datos , Humanos , Indoles/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Neoplasias Renales/mortalidad , Modelos de Riesgos Proporcionales , Pirroles/uso terapéutico , Tamaño de la Muestra , Sirolimus/análogos & derivados , Sirolimus/uso terapéutico , Sunitinib , Sobrevida
15.
EFSA J ; 20(10): e07584, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36304832

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-21314962

RESUMEN

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.


Asunto(s)
Carbono/uso terapéutico , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Carcinoma Hepatocelular/patología , Femenino , Humanos , Iones/uso terapéutico , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Dosificación Radioterapéutica , Adulto Joven
17.
BMC Cancer ; 11: 419, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-21961577

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Colorrectales/radioterapia , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundario , Linfocitos Infiltrantes de Tumor/efectos de la radiación , Anciano , Neoplasias Colorrectales/inmunología , Humanos , Neoplasias Hepáticas/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Persona de Mediana Edad , Dosificación Radioterapéutica
18.
J Pathol ; 220(5): 551-61, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20077528

RESUMEN

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.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Neoplasias Endometriales/metabolismo , Proteínas de Neoplasias/metabolismo , Molécula L1 de Adhesión de Célula Nerviosa/biosíntesis , Regulación hacia Arriba , Biomarcadores de Tumor/genética , Cadherinas/metabolismo , Neoplasias Endometriales/patología , Endometrio/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Técnicas para Inmunoenzimas , Invasividad Neoplásica/fisiopatología , Molécula L1 de Adhesión de Célula Nerviosa/genética , Pronóstico , ARN Neoplásico/genética , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Factores de Transcripción de la Familia Snail , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacos
19.
Nat Med ; 10(4): 389-95, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15004554

RESUMEN

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.


Asunto(s)
Axones/fisiología , Glicoproteínas de Membrana/antagonistas & inhibidores , Regeneración , Traumatismos de la Médula Espinal/fisiopatología , Animales , Supervivencia Celular , Proteína Ligando Fas , Ratones , Neuronas/citología , Pruebas de Neutralización , Oligodendroglía/citología , Traumatismos de la Médula Espinal/patología
20.
Lab Invest ; 90(10): 1482-91, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20479716

RESUMEN

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.


Asunto(s)
Cuello del Útero/metabolismo , Interferón Tipo I/metabolismo , Queratinocitos/metabolismo , Papillomaviridae , Infecciones por Papillomavirus/metabolismo , Neoplasias del Cuello Uterino/metabolismo , Cuello del Útero/patología , Cuello del Útero/virología , Regulación hacia Abajo , Femenino , Humanos , Interferón beta/metabolismo , Interferón gamma/metabolismo , Queratinocitos/patología , Queratinocitos/virología , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias del Cuello Uterino/inmunología , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
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