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1.
PLoS One ; 15(2): e0229271, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32084238

RESUMO

BACKGROUND: Truncated tissue factor (tTF) retargeted by NGR-peptides to aminopeptidase N (CD13) in tumor vasculature is effective in experimental tumor therapy. tTF-NGR induces tumor growth inhibition in a variety of human tumor xenografts of different histology. To improve on the therapeutic efficacy we have combined tTF-NGR with radiotherapy. METHODS: Serum-stimulated human umbilical vein endothelial cells (HUVEC) and human HT1080 sarcoma cells were irradiated in vitro, and upregulated early-apoptotic phosphatidylserine (PS) on the cell surface was measured by standard flow cytometry. Increase of cellular procoagulant function in relation to irradiation and PS cell surface concentration was measured in a tTF-NGR-dependent Factor X activation assay. In vivo experiments with CD-1 athymic mice bearing human HT1080 sarcoma xenotransplants were performed to test the systemic therapeutic effects of tTF-NGR on tumor growth alone or in combination with regional tumor ionizing radiotherapy. RESULTS: As shown by flow cytometry with HUVEC and HT1080 sarcoma cells in vitro, irradiation with 4 and 6 Gy in the process of apoptosis induced upregulation of PS presence on the outer surface of both cell types. Proapoptotic HUVEC and HT1080 cells both showed significantly higher procoagulant efficacy on the basis of equimolar concentrations of tTF-NGR as measured by FX activation. This effect can be reverted by masking of PS with Annexin V. HT1080 human sarcoma xenografted tumors showed shrinkage induced by combined regional radiotherapy and systemic tTF-NGR as compared to growth inhibition achieved by either of the treatment modalities alone. CONCLUSIONS: Irradiation renders tumor and tumor vascular cells procoagulant by PS upregulation on their outer surface and radiotherapy can significantly improve the therapeutic antitumor efficacy of tTF-NGR in the xenograft model used. This synergistic effect will influence design of future clinical combination studies.


Assuntos
Antineoplásicos/farmacologia , Antígenos CD13/metabolismo , Terapia de Alvo Molecular , Sarcoma/tratamento farmacológico , Sarcoma/radioterapia , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Antineoplásicos/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Coagulação Sanguínea/efeitos da radiação , Linhagem Celular Tumoral , Terapia Combinada , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos , Fosfatidilserinas/metabolismo , Sarcoma/metabolismo , Sarcoma/patologia
2.
Head Neck ; 37(8): 1137-41, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24764129

RESUMO

BACKGROUND: The registry for the evaluation of side effects after radiotherapy in childhood and adolescence (RiSK) was established to prospectively characterize radiation-associated side effects. The purpose of this analysis was to characterize side effects after radiotherapy to the head and neck in children and adolescents. METHODS: Radiation doses have been collected across Germany since 2001. Acute and late side effects were characterized. RESULTS: Until January 2010, 133 patients (median age, 12.7 years) were recruited who had received radiotherapy to the salivary glands. Toxicity evaluation was available for 114 patients (median follow-up, 2.9 years). Acute and late toxicity significantly depended on the maximum radiation dose to the salivary glands. An increase of the mean value of maximum dose of 1 Gray (Gy) to the submandibular glands resulted in an odds ratio of 1.04 (range, 1.00-1.08; p = .039) for acute toxicities of the salivary glands and 1.08 (range, 1.03-1.13; p = .001) for acute mucosal toxicities. CONCLUSION: These data can be used for an individual risk assessment in pediatric head and neck radiotherapy.


Assuntos
Relação Dose-Resposta à Radiação , Mucosa Bucal/efeitos da radiação , Lesões por Radiação/etiologia , Radioterapia Adjuvante/efeitos adversos , Glândulas Salivares/efeitos da radiação , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Alemanha/epidemiologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Lactente , Masculino , Estudos Prospectivos , Lesões por Radiação/epidemiologia , Compostos Radiofarmacêuticos , Dosagem Radioterapêutica , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo
3.
PLoS One ; 7(10): e47185, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23110060

RESUMO

Radiotherapy is a powerful cure for several types of solid tumours, but its application is often limited because of severe side effects in individual patients. With the aim to find biomarkers capable of predicting normal tissue side reactions we analysed the radiation responses of cells from individual head and neck tumour and breast cancer patients of different clinical radiosensitivity in a multicentric study. Multiple parameters of cellular radiosensitivity were analysed in coded samples of peripheral blood lymphocytes (PBLs) and derived lymphoblastoid cell lines (LCLs) from 15 clinical radio-hypersensitive tumour patients and compared to age- and sex-matched non-radiosensitive patient controls and 15 lymphoblastoid cell lines from age- and sex- matched healthy controls of the KORA study. Experimental parameters included ionizing radiation (IR)-induced cell death (AnnexinV), induction and repair of DNA strand breaks (Comet assay), induction of yH2AX foci (as a result of DNA double strand breaks), and whole genome expression analyses. Considerable inter-individual differences in IR-induced DNA strand breaks and their repair and/or cell death could be detected in primary and immortalised cells with the applied assays. The group of clinically radiosensitive patients was not unequivocally distinguishable from normal responding patients nor were individual overreacting patients in the test system unambiguously identified by two different laboratories. Thus, the in vitro test systems investigated here seem not to be appropriate for a general prediction of clinical reactions during or after radiotherapy due to the experimental variability compared to the small effect of radiation sensitivity. Genome-wide expression analysis however revealed a set of 67 marker genes which were differentially induced 6 h after in vitro-irradiation in lymphocytes from radio-hypersensitive and non-radiosensitive patients. These results warrant future validation in larger cohorts in order to determine parameters potentially predictive for clinical radiosensitivity.


Assuntos
Biomarcadores/análise , Tolerância a Radiação/fisiologia , Células Cultivadas , Ensaio Cometa , Dano ao DNA/fisiologia , Relação Dose-Resposta à Radiação , Histonas/metabolismo , Humanos , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , Radiação Ionizante
4.
BMC Cancer ; 12: 283, 2012 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-22780988

RESUMO

BACKGROUND: Recently published results of quality of life (QoL) studies indicated different outcomes of palliative radiotherapy for brain metastases. This prospective multi-center QoL study of patients with brain metastases was designed to investigate which QoL domains improve or worsen after palliative radiotherapy and which might provide prognostic information. METHODS: From 01/2007-01/2009, n=151 patients with previously untreated brain metastases were recruited at 14 centers in Germany and Austria. Most patients (82 %) received whole-brain radiotherapy. QoL was measured with the EORTC-QLQ-C15-PAL and brain module BN20 before the start of radiotherapy and after 3 months. RESULTS: At 3 months, 88/142 (62 %) survived. Nine patients were not able to be followed up. 62 patients (70.5 % of 3-month survivors) completed the second set of questionnaires. Three months after the start of radiotherapy QoL deteriorated significantly in the areas of global QoL, physical function, fatigue, nausea, pain, appetite loss, hair loss, drowsiness, motor dysfunction, communication deficit and weakness of legs. Although the use of corticosteroid at 3 months could be reduced compared to pre-treatment (63 % vs. 37 %), the score for headaches remained stable. Initial QoL at the start of treatment was better in those alive than in those deceased at 3 months, significantly for physical function, motor dysfunction and the symptom scales fatigue, pain, appetite loss and weakness of legs. In a multivariate model, lower Karnofsky performance score, higher age and higher pain ratings before radiotherapy were prognostic of 3-month survival. CONCLUSIONS: Moderate deterioration in several QoL domains was predominantly observed three months after start of palliative radiotherapy for brain metastases. Future studies will need to address the individual subjective benefit or burden from such treatment. Baseline QoL scores before palliative radiotherapy for brain metastases may contain prognostic information.


Assuntos
Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Cuidados Paliativos , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Inquéritos e Questionários
5.
Anticancer Res ; 31(11): 3903-8, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22110217

RESUMO

AIM: To assess the overall impact of the most common contemporary prostate cancer therapies (radical prostatectomy, percutaneous irradiation, brachytherapy, hormonal therapy) with regard to physical and psychological well-being, as well as to general patient satisfaction. PATIENTS AND METHODS: In October 2006, a questionnaire focused on patients' opinions and satisfaction regarding their previous prostate cancer therapies was published in a patient cancer journal (Krebsmagazin). Results were collected until March, 2007 and analyzed using Wilcoxon and Student's t-tests. RESULTS: Answers were obtained from 634 patients (radical prostatectomy: 61%; percutaneous irradiation: 17%; brachytherapy: 2%; hormonal therapy: 15%; other/combined: 5%). Concerning late side effects and convenience of treatment, 96% of all patients who had undergone percutaneous irradiation were very satisfied with their choice and would choose the same therapy again (brachytherapy: 93%; hormonal therapy: 84%; radical prostatectomy: 79%). Erectile dysfunction with inability to perform sexual intercourse was reported by 32% of all patients who underwent percutaneous irradiation (brachytherapy: 21%; hormonal therapy: 63%; radical prostatectomy: 52%). No sexual problems at all were reported by 22% of patients who underwent percutaneous irradiation (brachytherapy: 21%; hormonal therapy: 13%; radical prostatectomy: 4%). With regard to psychological and physical deficits (fear; depression; urinary, bowel, erectile dysfunction; hormonal disorders), percutaneous irradiation was superior to the other treatment options (no deficits: percutaneous irradiation; 49%; brachytherapy: 36%; hormonal therapy: 17%; radical prostatectomy: 15%). CONCLUSION: Radiotherapy showed superior results regarding patient convenience and satisfaction in comparison to hormonal therapy and surgery in the treatment of patients with prostate cancer.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Braquiterapia , Satisfação do Paciente , Prostatectomia , Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Seguimentos , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/psicologia , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários
6.
Strahlenther Onkol ; 187(5): 311-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21533759

RESUMO

PURPOSE: Total body irradiation (TBI) is a standard treatment modality within the multidisciplinary approach for allogeneous stem cell or bone marrow transplantation. However, surviving patients are at risk for developing a variety of late sequelae. This analysis aimed to retrospectively characterize late effects after TBI in adults treated in a single center. PATIENTS AND METHODS: Patients ≥ 18 years treated with fractionated TBI (4-12 Gy) between 1996 and 2008 were included in this study. Treatment data were collected retrospectively from the treating departments. Late effects were evaluated using the clinic charts and/or were obtained from the general practitioners using a standardized questionnaire. Analyses were performed by calculation of the cumulative incidences using the Kaplan-Meier method and the log rank test. RESULTS: A total of 308 patients ≥ 18 years were treated including a TBI of whom 78 patients were excluded from further analysis due to death within less than 1 year after TBI. Patients suffered from leukemia in most cases. Late toxicity follow-up was available in 120 patients (mean age 46.1 years; range, 18-70 years) after a mean follow-up of 23 months (range, 12-96 months). The cumulative incidences (CI) at 3 years were 28% for pulmonary event, 8% for pulmonary toxicity, 25% for kidney toxicity, 8% for cataract, 17% for bone toxicity, and 10% for secondary malignancy. The CI of bone toxicity was higher in female than in male patients (p = 0.019). CONCLUSION: Late effects after TBI in the context of allogeneous stem cell or bone marrow transplantation can frequently be observed. Regular follow-up examinations are advised for the early registration and treatment of adverse effects.


Assuntos
Irradiação Corporal Total/efeitos adversos , Adulto , Idoso , Transplante de Medula Óssea/métodos , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores Sexuais , Transplante de Células-Tronco/métodos , Fatores de Tempo , Adulto Jovem
7.
Pediatr Blood Cancer ; 57(4): 549-53, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21442722

RESUMO

BACKGROUND: The prognosis in patients with relapsed Ewing sarcoma is unfavorable. Our investigation identifies factors predicting for the outcome following relapse. PROCEDURE: We analyzed type of relapse, time to relapse and overall survival after relapse (OSr) in 714 patients with first recurrence. All patients had been treated within the Cooperative Ewing Sarcoma Studies (CESS) 81 or 86, or the European Intergroup CESS (EICESS 92). OSr time was calculated from diagnosis of first relapse to last follow-up or death. RESULTS: Median follow-up time from diagnosis of primary disease was 2.2 years (mean = 4.0; range: 0.2-24.9). Relapse sites were local in 15%, combined local and systemic in 12%, and systemic in 73%. Among patients with a localized primary tumor, 20% relapsed locally, while 12% showed combined and 68% systemic relapse. When the primary disease was disseminated, 82% developed systemic, 13% combined, and 5% local relapse. Five-year OSr was 0.13 (SE = 0.01). Outcome following local relapse, with a 5-year survival rate of 0.24 (P < 0.001), was superior to outcome after systemic or combined recurrence. Five-year OSr was 0.07 (SE = 0.01) in patients who relapsed 0-2 years after the diagnosis of primary disease, as compared to a 5-year OSr of 0.29 (SE = 0.03) when relapse occurred later. CONCLUSIONS: 5-year OSr in Ewing sarcoma is poor (<0.2). Prognostically favorable factors are: late onset (>2 years) and strictly localized relapse.


Assuntos
Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Sarcoma de Ewing/mortalidade , Sarcoma de Ewing/patologia , Adolescente , Adulto , Neoplasias Ósseas/terapia , Criança , Pré-Escolar , Terapia Combinada , Feminino , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Prognóstico , Sarcoma de Ewing/terapia , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Int J Radiat Oncol Biol Phys ; 81(5): e787-91, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21167655

RESUMO

PURPOSE: The "Registry for the Evaluation of Side Effects After Radiotherapy in Childhood and Adolescence" (RiSK) has been established to prospectively characterize dose-volume effects of radiation in terms of side effects. The aim of this analysis was to characterize the function of the thyroid gland after radiotherapy to the head-and-neck region in children and adolescents. METHODS AND MATERIALS: Detailed information regarding radiation doses to at-risk organs has been collected across Germany since 2001. Thyroid function was evaluated by blood value examinations of thyroid-stimulating hormone, triiodothyronine, and thyroxine. Information regarding thyroid hormone substitution was requested from the treating physicians. RESULTS: Until May 2009, 1,086 patients from 62 centers were recruited, including 404 patients (median age, 10.9 years) who had received radiotherapy to the thyroid gland and/or hypophysis. Follow-up information was available for 264 patients (60.9%; median follow-up, 40 months), with 60 patients (22.7%) showing pathologic values. In comparison to patients treated with prophylactic cranial irradiation (median dose, 12 Gy), patients with radiation doses of 15 to 25 Gy to the thyroid gland had a hazard ratio of 3.072 (p=0.002) for the development of pathologic thyroid blood values. Patients with greater than 25 Gy to the thyroid gland and patients who underwent craniospinal irradiation had hazard ratios of 3.768 (p=0.009) and 5.674 (p<0.001), respectively. The cumulative incidence of thyroid hormone substitution therapy did not differ between defined subgroups. CONCLUSIONS: Radiation-induced thyroid function impairment, including damage to the thyroid gland and/or hypophysis, can frequently be observed after radiotherapy in children. A structured follow-up examination is advised.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Hipotireoidismo/etiologia , Órgãos em Risco/efeitos da radiação , Sistema de Registros , Glândula Tireoide/efeitos da radiação , Adolescente , Criança , Pré-Escolar , Irradiação Craniana/efeitos adversos , Alemanha , Terapia de Reposição Hormonal/estatística & dados numéricos , Humanos , Hipotireoidismo/sangue , Hipotireoidismo/tratamento farmacológico , Lactente , Estudos Longitudinais , Hipófise/efeitos da radiação , Dosagem Radioterapêutica , Risco , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Adulto Jovem
9.
Int J Radiat Oncol Biol Phys ; 80(3): 840-4, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20638187

RESUMO

PURPOSE: To characterize kidney function in children and adolescents who had undergone radiation treatment that included parts of the kidney. METHODS AND MATERIALS: Patients receiving radiotherapy during childhood or adolescence were prospectively registered in Germany's Registry for the Evaluation of Side Effects after Radiation in Childhood and Adolescence (RiSK). Detailed information was recorded regarding radiation doses at the organs at risk since 2001 all over Germany. Toxicity evaluation was performed according to standardized Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria. RESULTS: Up to May 2009, 1086 patients from 62 centers were recruited, including 126 patients (median age, 10.2 years) who underwent radiotherapy to parts of the kidneys. Maximal late toxicity (median follow-up 28.5 months in 74 patients) was characterized as Grade 0 (n = 65), 1 (n = 7) or 2 (n = 2). All patients with late effects had received potentially nephrotoxic chemotherapy. A statistically significant difference between patients with and without Grade 1 toxicity, revealing higher exposed kidney volumes in patients with toxicity, was seen for the kidney volume exposed to 20 Gy (V20; p = 0.031) and 30 Gy (V30; p = 0.003). CONCLUSIONS: Preliminary data indicate that radiation-induced kidney function impairment is rare in current pediatric multimodal treatment approaches. In the future, RiSK will be able to provide further detailed data regarding dose-volume effect relationships of radiation-associated side effects in pediatric oncology patients.


Assuntos
Nefropatias/etiologia , Rim/efeitos da radiação , Lesões por Radiação/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Alemanha , Humanos , Lactente , Rim/efeitos dos fármacos , Nefropatias/patologia , Neoplasias/radioterapia , Órgãos em Risco/patologia , Órgãos em Risco/efeitos da radiação , Estudos Prospectivos , Lesões por Radiação/patologia , Dosagem Radioterapêutica , Sistema de Registros , Adulto Jovem
10.
Pediatr Blood Cancer ; 55(6): 1145-52, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20734400

RESUMO

BACKGROUND: To analyze the impact of mediastinal irradiation on the incidence of cardiac late effects in long-term survivors of pediatric Hodgkin disease (HD). METHODS: The study cohort comprised 1,132 survivors of HD who received treatment before 18 years of age in consecutive trials between 1978 and 1995. They had maintained remission without secondary malignancy for 3.1-29.4 years. The cumulative doxorubicin dose was uniformly 160 mg/m(2), the mediastinal radiation dose (MedRD) was 36, 30, 25, 20, or 0 Gy. Follow-up questionnaires complemented by additional contacts served to collect information on late effects from patients and physicians. A central expert panel reviewed all reported cardiac abnormalities. RESULTS: By October 2008, cardiac diseases (CD) had been diagnosed in 50 of 1,132 patients aged 15.0-41.7 (median 32.2) years. The interval since HD therapy was 3.0-28.2 (median 19.5) years. Valvular defects were diagnosed most frequently, followed by coronary artery diseases, cardiomyopathies, conduction disorders, and pericardial abnormalities. The cumulative incidence of CD after 25 years was highest in the MedRD-36 group (21%) decreasing to 10%, 6%, 5%, and 3% in the lower MedRD groups (P < 0.001). Multivariate Cox analysis of several putative risk factors showed MedRD to be the only significant variable predicting for CD-free survival (P = 0.0025). CONCLUSIONS: Our results indicate that lower MedRDs are less cardiotoxic. Consequently, reduction of cardiac late effects may be expected with the lower radiation doses used in current HD protocols. Longer follow-up is needed to confirm the present results.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cardiopatias/etiologia , Doenças das Valvas Cardíacas/etiologia , Doença de Hodgkin/radioterapia , Neoplasias do Mediastino/radioterapia , Adolescente , Criança , Pré-Escolar , Terapia Combinada , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Cardiopatias/diagnóstico , Doenças das Valvas Cardíacas/diagnóstico , Doença de Hodgkin/complicações , Doença de Hodgkin/tratamento farmacológico , Humanos , Estudos Longitudinais , Masculino , Neoplasias do Mediastino/complicações , Neoplasias do Mediastino/tratamento farmacológico , Prednisona/administração & dosagem , Procarbazina/administração & dosagem , Dosagem Radioterapêutica , Taxa de Sobrevida , Resultado do Tratamento , Vincristina/administração & dosagem
11.
Anticancer Res ; 30(7): 2857-61, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20683023

RESUMO

AIM: To characterize the interaction of tumour necrosis factor alpha (TNF-alpha) and ionising radiation in six sarcoma, lymphoma and carcinoma cell lines. MATERIALS AND METHODS: Cells were characterized regarding annexin V/propiduim iodine affinity and caspase-3 status after application of TNF-alpha, radiation, or combined treatment. RESULTS: Three cell lines showed similar results with additive effects of TNF-alpha and radiation in both assays. The other three cell lines significantly differed regarding the detection of apoptotic cells between treatment conditions (radiation and/or TNF application) and between the two apoptosis assays. CONCLUSION: The interaction between TNF-alpha and radiation differs between tumour entities and cannot be described by using only one parameter.


Assuntos
Apoptose/efeitos da radiação , Carcinoma/radioterapia , Linfoma/radioterapia , Sarcoma/radioterapia , Fator de Necrose Tumoral alfa/farmacologia , Anexina A5/metabolismo , Apoptose/efeitos dos fármacos , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Carcinoma/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Humanos , Linfoma/tratamento farmacológico , Linfoma/metabolismo , Linfoma/patologia , Sarcoma/tratamento farmacológico , Sarcoma/metabolismo , Sarcoma/patologia
12.
Radiat Oncol ; 5: 66, 2010 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-20642823

RESUMO

BACKGROUND: Telomerase activity compensates shortening of telomeres during cell division and enables cancer cells to escape senescent processes. It is also supposed, that telomerase is associated with radio- and chemoresistance. In the here described study we systematically investigated the influence of telomerase activity (TA) and telomere length on the outcome of radio- and chemotherapy in neuroblastoma. METHODS: We studied the effects on dominant negative (DN) mutant, wild type (WT) of the telomerase catalytic unit (hTERT) using neuroblastoma cell lines. The cells were irradiated with 60Co and treated with doxorubicin, etoposide, cisplatin and ifosfamide, respectively. Viability was determined by MTS/MTT-test and the GI50 was calculated. Telomere length was measured by southernblot analysis and TA by Trap-Assay. RESULTS: Compared to the hTERT expressing cells the dominant negative cells showed increased radiosensitivity with decreased telomere length. Independent of telomere length, telomerase negative cells are significantly more sensitive to irradiation. The effect of TA knock-down or overexpression on chemosensitivity were dependent on TA, the anticancer drug, and the chemosensitivity of the maternal cell line. CONCLUSIONS: Our results supported the concept of telomerase inhibition as an antiproliferative treatment approach in neuroblastomas. Telomerase inhibition increases the outcome of radiotherapy while in combination with chemotherapy the outcome depends on drug- and cell line and can be additive/synergistic or antagonistic. High telomerase activity is one distinct cancer stem cell feature and the here described cellular constructs in combination with stem cell markers like CD133, Aldehyddehydrogenase-1 (ALDH-1) or Side population (SP) may help to investigate the impact of telomerase activity on cancer stem cell survival under therapy.


Assuntos
Resistencia a Medicamentos Antineoplásicos/fisiologia , Neuroblastoma/enzimologia , Tolerância a Radiação/fisiologia , Telomerase/metabolismo , Southern Blotting , Linhagem Celular Tumoral , Humanos , Transfecção
13.
Radiother Oncol ; 97(1): 119-26, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20605649

RESUMO

BACKGROUND AND PURPOSE: The "Registry for the evaluation of side effects after radiation in childhood and adolescence" (risk) was introduced to characterize adverse effects of radiotherapy in childhood and adolescence prospectively. The aim of this analysis was to characterize the pattern of acute side effects. MATERIALS AND METHODS: Since 2001, patients receiving radiotherapy in one of the German pediatric therapy trials have been registered in RiSK with detailed information regarding radiation doses to organs at risk and characterization of acute toxicities. RESULTS: From 2001 to May 2009, 690 patients have been characterized for acute toxicity in primary therapy. Acute toxicity ≥ grade 1 was observed in 506 patients. In patients irradiated in their lung and liver, patients with grade 1 or 2 acute toxicities showed higher organ volumes exposed to radiation doses <20 Gray (Gy) compared to patients without toxicities. For the salivary glands, there was a positive correlation between the acute toxicity grade and the maximum radiation dose to the organ; the lower GI tract showed a similar trend. The impact of different chemotherapy regimens on these acute side effects remains unclear. Age did not have any impact on side effects. CONCLUSION: This analysis gives a comprehensive overview of the acute toxicities of radiotherapy in children and adolescents. With prolongation of follow-up, detailed analyses regarding late toxicities will be possible with the characterization of dose-volume-effect relationships.


Assuntos
Neoplasias/radioterapia , Lesões por Radiação/radioterapia , Radioterapia/efeitos adversos , Sistema de Registros , Adolescente , Criança , Feminino , Alemanha , Humanos , Masculino , Estudos Prospectivos , Dosagem Radioterapêutica , Medição de Risco , Estatísticas não Paramétricas
15.
Anticancer Res ; 30(1): 227-31, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20150640

RESUMO

AIM: To comprehensively summarize the most important literature regarding the late effects of radiotherapy to the abdomen in childhood and adolescence. MATERIALS AND METHODS: Published trials, studies and series were identified using the PubMed database. The key words late effects, late sequelae, child, radiation, radiotherapy, abdomen, kidney, liver, and bowel were used. RESULTS: A dose-volume effect is confirmed for liver irradiation. Radiation with doses <20 Gy to major parts of the liver or higher doses to smaller parts seems to be safe. Kidney function impairment due to radiation is rare in children. Renal sequelae may occur after radiation to the remaining kidney in patients who underwent nephrectomy or who received higher doses to both kidneys. Several reports describe small bowel obstruction as a sequelae of surgery, but radiotherapy seems to be less important. CONCLUSION: Several retrospective reports describe radiation-associated late sequelae in children. However, there is still a lack of sufficient data regarding the characterization of dose-volume effects.


Assuntos
Abdome/efeitos da radiação , Lesões por Radiação/etiologia , Criança , Relação Dose-Resposta à Radiação , Humanos , Intestinos/efeitos da radiação , Rim/efeitos da radiação , Fígado/efeitos da radiação , Radioterapia/efeitos adversos
18.
Strahlenther Onkol ; 185 Suppl 2: 21-2, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19685030
19.
Anticancer Res ; 29(8): 3397-400, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19661363

RESUMO

BACKGROUND: A 28-year-old man suffering from a Ewing tumour arising from the 9th-11th ribs with infiltration of neuroforamina without distant metastases was planned to receive radiotherapy following primary intralesional surgery and induction chemotherapy. Due to pleural infiltration and effusion, a hemithorax irradiation with a sequential boost to the primary tumour site had to be administered. Different treatment planning variants failed to provide sufficient radiotherapy planning in view of target volume coverage and avoidance of organs at risk, especially due to high calculated radiation doses potentially compromising the left kidney. MATERIALS AND METHODS: To prevent left kidney organ exposure, an autotransplantation of the left kidney into the right fossa iliaca was performed. An infiltration of the kidney was initially excluded. RESULTS: Postoperatively, a renal scintigraphy showed a normal function of both kidneys allowing sufficient radiotherapy treatment planning. Target volume coverage was easily obtained using a combination of hemithorax irradiation and a sequential boost by an intensity-modulated-radiotherapy technique. CONCLUSION: In difficult individual treatment situations, surgical transpositions as well as organ autotransplantation might be useful in reducing radiotherapy organ dose levels.


Assuntos
Neoplasias Ósseas/cirurgia , Transplante de Rim , Sarcoma de Ewing/cirurgia , Adulto , Neoplasias Ósseas/patologia , Neoplasias Ósseas/radioterapia , Humanos , Rim/efeitos da radiação , Rim/cirurgia , Imageamento por Ressonância Magnética , Masculino , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Sarcoma de Ewing/patologia , Sarcoma de Ewing/radioterapia , Transplante Autólogo
20.
Strahlenther Onkol ; 185(5): 275-81, 2009 May.
Artigo em Alemão | MEDLINE | ID: mdl-19440665

RESUMO

BACKGROUND AND PURPOSE: A sufficient number of well-trained specialists in radiation oncology is needed for an adequate supply in radiation oncology. Therefore, the training in radiation oncology is of utmost importance. This requirement is faced with a growing lack of physicians in Germany. The aim of this study was to characterize the current situation of radiation oncology training in Germany and to work out proposals to avoid a lack of radiotherapists. MATERIAL AND METHODS: In summer 2008, 233 questionnaires were sent out to potential trainers in radiation oncology in Germany. The questions included, among others, the individual training situation and problems in finding physicians. A second questionnaire was addressed to trainees in radiation oncology and contained, e.g., questions regarding satisfaction, motivation for the choice of radiation oncology, a previous work in another discipline, and future perspectives. RESULTS: Answers were obtained from 107 supervisor physicians of whom 84.1% had the permission to employ trainees in radiation oncology. The finding of new trainees provided large problems in 47.1%; 35.3% had few and 17.6% no problems. For specialists in radiation oncology, 47.2% reported large, 26.4% few and 26.4% no problems in finding candidates. 113 trainees answered the questionnaires. Almost half of them (46.9%) had previously worked in another discipline. The majority was quite (44.2%) or fully (46.0%) satisfied with their job, 84.1% stated good up to excellent future perspectives. The vast majority (88.5%) would decide for a training in radiation oncology again. CONCLUSION: Trainees in radiation oncology in Germany are satisfied with their training, see good future perspectives and would again decide to do their training in radiation oncology. However, there are large problems in finding candidates for open jobs. A positive promotion is recommended to face these problems.


Assuntos
Avaliação Educacional , Radioterapia (Especialidade)/educação , Radioterapia (Especialidade)/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Alemanha
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