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1.
Brain Spine ; 4: 102740, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510629

RESUMO

Introduction: The reconstruction of frontobasal defects following oncologic resections of paranasal and anterior skull base (ASB) malignancies remains challenging. Ineffective reconstruction could lead to cerebrospinal fluid leak, meningitis, and tension pneumocephalus. Research question: Aim of this investigation was to analyse postoperative complication rates with or without bone graft for anterior skull base reconstruction. Material and methods: In this retrospective study, we included patients following resection of paranasal and/or anterior skull base malignancies between October 2013 and December 2022. Complications were analysed with regards to the type of skull base reconstruction. Results: Eleven patients were identified (2 female, 9 male, age (median, SD) 64 ± 14.1 years (range 38-81). There were nine cases of paranasal sinus and nasal cavity carcinomas and two cases of olfactory neuroblastomas. Overall survival was 22.5 ± 28 months (range: 5-78), progression free survival was 17.0 ± 20.3 months (range: 11-78). Bone skull base reconstruction using a split graft was performed in three cases. Postoperative complications requiring surgical intervention were seen in 33% (one tension pneumocephalus) of cases in the bone reconstruction group and 50% (three patients with cerebrospinal fluid leak, one infection) in the non-bone reconstruction group. Discussion and conclusion: The structural reinforcement of structural bone chip grafting might provide additional support of the ASB and prevent CSF leakage or encephalocele. Especially in large (>10 cm2) bone defects of advanced sinonasal malignancies extending into the middle cranial fossa, the full armamentarium of reconstruction possibilities should be considered.

2.
Strahlenther Onkol ; 198(12): 1105-1111, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36149437

RESUMO

PURPOSE: Does focal cavity radiotherapy after resection of brain metastasis "spare" whole-brain radiotherapy, which is associated with toxicity for patients, through the complete course of their disease without compromising long-term local control of the brain? METHODS: We retrospectively analyzed outcomes of patients who underwent adjuvant focal cavity radiotherapy between 2014 and 2021 at our center. RESULTS: A total of 83 patients with 86 resected brain metastases were analyzed. 64% had singular, 36% two to four brain metastases. In cases with multiple metastases, omitted lesions were treated with radiosurgery. Median follow-up was 7.3 months (range 0-71.2 months), 1­year overall survival rate was 57.8% (95% CI 44.9-68.8%). Radiotherapy was administered with a median biologically effective dose (α/ß 10) surrounding the planning target volume of 48 Gy (range 23.4-60 Gy). Estimated 1­year local control rate was 82.7% (95% CI 67.7-91.2%), estimated 1­year distant brain control rate was 55.7% (95% CI 40.5-68.4%), estimated 1­year leptomeningeal disease rate was 16.0% (95% CI 7.3-32.9%). Eleven distant brain recurrences could be salvaged with radiosurgery. In the further course of disease, 14 patients (17%) developed disseminated metastatic disease in the brain. Estimated 1­year free of whole-brain radiotherapy rate was 72.3% (95% CI 57.1-82.9%). All applied treatments led to an estimated 1­year neuro-control rate of 79.1% (95% CI 65.0-88.0%), estimated 1­year radionecrosis rate was 23% (95% CI 12.4-40.5%). CONCLUSION: In our single-center study, focal cavity radiotherapy was associated with high local control. In three out of four patients, whole-brain radiotherapy could be avoided in the complete course of disease, using radiosurgery as salvage approach without compromising neuro-control.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Humanos , Estudos Retrospectivos , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/secundário , Terapia de Salvação , Radioterapia Adjuvante , Irradiação Craniana
3.
Strahlenther Onkol ; 197(12): 1124-1130, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34415358

RESUMO

PURPOSE: External-beam radiotherapy (EBRT) is the predominant method for localized brain radiotherapy (LBRT) after resection of brain metastases (BM). Intraoperative radiotherapy (IORT) with 50-kV x­rays is an alternative way to focally irradiate the resection cavity after BM surgery, with the option of shortening the overall treatment time and limiting normal tissue irradiation. METHODS: We retrospectively analyzed the outcomes of all patients who underwent neurosurgical resection of BM and 50-kV x­ray IORT between 2013 and 2020 at Augsburg University Medical Center. RESULTS: We identified 40 patients with 44 resected BM treated with 50-kV x­ray IORT. Median diameter of the resected metastases was 2.8 cm (range 1.5-5.9 cm). Median applied dose was 20 Gy. All patients received standardized follow-up (FU) including 3­monthly MRI of the brain. Mean FU was 14.4 months, with a median MRI FU for alive patients of 12.2 months. Median overall survival (OS) of all treated patients was 26.4 months (estimated 1­year OS 61.6%). The observed local control (LC) rate of the resection cavity was 88.6% (estimated 1­year LC 84.3%). Distant brain control (DC) was 47.5% (estimated 1­year DC 33.5%). Only 25% of all patients needed WBI in the further course of disease. The observed radionecrosis rate was 2.5%. CONCLUSION: IORT with 50-kV x­rays is a safe and appealing way to apply LBRT after neurosurgical resection of BM, with low toxicity and excellent LC. Close MRI FU is paramount to detect distant brain failure (DBF) early.


Assuntos
Neoplasias Encefálicas , Centros Médicos Acadêmicos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Humanos , Recidiva Local de Neoplasia/radioterapia , Radiografia , Estudos Retrospectivos , Raios X
4.
Oncol Res Treat ; 43(7-8): 372-379, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32485721

RESUMO

INTRODUCTION: Esophageal cancer (EC) is a common malignant tumor entity with increasing occurrence. The incidence of esophageal adenocarcinoma (AC), particularly, is constantly rising in the Western world. The mainstays of therapy with curative intent for EC in advanced stages are neoadjuvant radiochemotherapy (neoRCT) with surgery and definitive radiochemotherapy (defRCT). METHODS: We examined our internal files to identify patients suffering from EC. Palliative cases were excluded. Statistical testing was performed by χ2 test, Student's t test, Kaplan-Meier analyses, and the Mann-Whitney U test. RESULTS: One hundred and twenty-two cases were included. Histology revealed squamous cell carcinoma in 92 cases and AC in 23 cases. Ninety-five patients underwent defRCT, 27 underwent neoRCT, and 114 (in both therapy regimes) received simultaneous chemotherapy. There was no difference in the overall survival (OS) (p = 0.654; HR 1.145; 95% CI 0.629-2.086) or and progression-free survival (PFS) (p = 0.912) of patients who underwent neoRCT or defRCT. Median OS was 13.5 (2-197) months for defRCT patients and 19.5 (2-134) months for neoRCT patients (p = 0.751). Karnofsky index (KI) with a cut-off of 70% was strongest, but not a significant parameter for OS (p = 0.608) or PFS (p = 0.137). CONCLUSION: defRCT is a valid and an equal alternative to neoRCT for patients suffering from EC. Selection of patients for therapy is of crucial relevance. Further studies and improvements in follow-up are needed when neoRCT has been completed before surgery, in order to spare the patient undergoing operative treatment if there is complete remission. The identification of valid markers urgently needed to limit treatment side effects.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia Adjuvante/mortalidade , Neoplasias Esofágicas/terapia , Terapia Neoadjuvante/mortalidade , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Intervalo Livre de Doença , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Strahlenther Onkol ; 195(6): 544-557, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30859254

RESUMO

PURPOSE: Long-term impact of stage-adapted field reduction in a large cohort of gastric marginal zone lymphoma (gMZL) patients treated conservatively with curative radiation therapy (RT). PATIENTS AND METHODS: Prospective analysis of paper records of 290 patients with stage IE-IIE gMZL, treated in 78 radiotherapeutic institutions in Germany from 1992-2013. Stage-adapted radiation fields decreased from extended field (EF) to involved field (IF) over the course of three consecutive prospective trials of the German Study Group on Gastrointestinal Lymphoma (DSGL). Treatment results were compared between the three cohorts. RESULTS: Overall collective with median age of 60 years, slight male predominance (m:f = 1.1:1) and ratio of disease stage I:stage II = 2.1:1. Median follow-up 6.4 years in total: 13.0 years in the first gastrointestinal study (GIT 1992), 8.2 years in the second (GIT 1996) and 4.7 years in the third study (DSGL 01/2003). Stage-adapted radiation field decrease together with further technological development led to reduced relative frequencies of acute/chronic adverse effects and until now was accompanied by lower disease recurrence. The third study design with smallest field size (IF in stage I, locoregional EF in stage II) achieved the best survival outcome at the 5­year follow-up (overall survival 92.7%, event-free survival 89.5% and lymphoma-specific survival 100.0%). Disease relapse observed in 10 patients. Cumulative incidence of disease-specific death was 1.7% of the followed patients. Primary disease stage associated with lymphoma-specific survival. CONCLUSION: Stage-adapted reduction towards IF in gMZL resulted in favorable adverse effects, local control and survival rates. These results support further decreases in modern RT of gMZL.


Assuntos
Linfoma de Zona Marginal Tipo Células B/radioterapia , Neoplasias Gástricas/radioterapia , Idoso , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Linfoma de Zona Marginal Tipo Células B/mortalidade , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Estudos Prospectivos , Doses de Radiação , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
6.
Oncology ; 76(6): 405-12, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19407473

RESUMO

OBJECTIVE: Hyperfractionated accelerated radiotherapy (HART) has been combined with chemotherapy (CC) for locally advanced head and neck cancer, but no data from randomized trials are available for a comparison with conventionally fractionated radiotherapy (CFRT) and CC. METHODS: This monoinstitutional retrospective study compares the results of both treatment schedules: 315 patients with locally advanced carcinoma (UICC stage III and IV) of the oral cavity and the orohypopharynx were treated from January 1990 to March 2006 with a radiochemotherapy combination based on mitomycin C and fluorouracil (HART-CC: 203 patients, CFRT-CC: 112 patients, total dose: 70-72 Gy) with curative intent. RESULTS: Two- and 4-year survival was 60 and 42 (HART-CC) and 59 and 42% (CFRT-CC; p = 0.82, log-rank test), respectively. Using multivariate Cox regression, pretreatment hemoglobin level, N stage, tumor site but not the year of treatment, gender and T stage were significant prognosticators for survival. For locoregional control, only N stage was significant. The prognostic value of these pretreatment factors did not variate with the fractionation schedule used. CONCLUSIONS: In combination with CC, there was no trend towards an improved efficacy of HART in comparison with CFRT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Carcinoma/radioterapia , Fracionamento da Dose de Radiação , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Idoso , Terapia Combinada/métodos , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Análise de Regressão , Estudos Retrospectivos , Resultado do Tratamento
7.
J Clin Oncol ; 25(31): 4987-92, 2007 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-17971598

RESUMO

PURPOSE: To investigate the role of prophylactic cranial irradiation (PCI) within a trimodality protocol (chemotherapy, chemoradiotherapy, surgery) for patients with operable stage IIIA non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: After mediastinoscopic staging, patients with operable stage IIIA NSCLC were enrolled to a German multicenter trial and randomly assigned to receive either primary resection followed by adjuvant thoracic radiation therapy (50 to 60 Gy; arm A) or preoperative chemotherapy (cisplatin/etoposide [PE]; three cycles) followed by concurrent chemoradiotherapy (PE plus 45 Gy; 1.5 Gy twice per day) and definitive surgery (arm B), respectively. Patients in arm B were scheduled to receive PCI (30 Gy; 2 Gy daily fractions). RESULTS: One hundred twelve patients were randomly assigned between November 1994 and July 2001. One hundred six patients were eligible (arm A: 51, arm B: 55), 90 males and 16 females, 50 with squamous cell, 16 with large cell, five with adenosquamous, and 35 with adenocarcenoma (median age, 57 years; range, 37 to 71 years). Forty-three patients received PCI as scheduled in arm B. Eleven long-term survivors (arm A: four; arm B: seven) underwent a comprehensive neuropsychological examination. PCI significantly reduced the probability of brain metastases as first site of failure (7.8% at 5 years v 34.7%; P = .02), the overall brain relapse rate was reduced comparably (9.1% at 5 years v 27.2%; P = .04). A slightly reduced neurocognitive performance in comparison with the age-matched normal population was found for patients in both treatment groups. No significant difference between patients who were treated with or without PCI could be noted. CONCLUSION: PCI is effective in preventing brain metastases following this aggressive trimodality approach. Neurocognitive late effects are not significantly different between patients treated with or without PCI.


Assuntos
Neoplasias Encefálicas/prevenção & controle , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/terapia , Adulto , Idoso , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/terapia , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/terapia , Terapia Combinada , Feminino , Alemanha , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante
8.
Lab Anim ; 41(2): 239-46, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17430623

RESUMO

The implantation of tumour cells in normal tissues and the subsequent induction of angiogenesis by the growing xenograft were studied by means of immunohistochemistry and digital image analysis. Tumour growth was induced by injection of a human spindle cell sarcoma (ES3) into the subcutis of HsdCpb:NMRI-nu/nu mice. In vivo injection of Hoechst 33342 was used as a marker of perfusion. The vasculature was stained with specific antibodies and subsequently analysed by digital image analysis. Starting at day 3 up to day 6, angiogenesis could be detected and the relative amount of perfusion within the investigated area reached a peak at day 6. This method, which allows investigation of both functional and morphometric characteristics of human xenograft vasculature, serves as an excellent assay for evaluation of antiangiogenic therapies in translational research of experimental tumours.


Assuntos
Neovascularização Patológica/metabolismo , Sarcoma/irrigação sanguínea , Animais , Feminino , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Nus , Modelos Biológicos , Transplante de Neoplasias , Fatores de Tempo , Transplante Heterólogo
9.
Strahlenther Onkol ; 179(9): 620-5, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14628128

RESUMO

BACKGROUND: Pronounced oxygen deficiency in tumors which might be caused by a diminished oxygen transport capacity of the blood (e.g., in anemia) reduces the efficacy of ionizing radiation. The aim of this study was to analyze whether anemia prevention by recombinant human erythropoietin (rHuEPO) affects the radiosensitivity of human glioblastoma xenografts during fractionated irradiation. MATERIAL AND METHODS: Anemia was induced by total body irradiation (TBI, 2 x 4 Gy) of mice prior to tumor implantation into the subcuts of the hind leg. In one experimental group, the development of anemia was prevented by rHuEPO (750 U/kg s.c.) given three times weekly starting 10 days prior to TBI. 13 days after tumor implantation (tumor volume approx. 40 mm3), fractionated irradiation (4 x 7 Gy, one daily fraction) of the glioblastomas was performed resulting in a growth delay with subsequent regrowth of the tumors. RESULTS: Compared to nonanemic control animals (hemoglobin concentration cHb = 14.7 g/dl), the growth delay in anemic mice (cHb = 9.9 g/dl) was significantly shorter (49 +/- 5 days vs. 79 +/- 4 days to reach four times the initial tumor volume) upon fractionated radiation. The prevention of anemia by rHuEPO treatment (cHb = 13.3 g/dl) resulted in a significantly prolonged growth delay (61 +/- 5 days) compared to the anemia group, even though the growth inhibition found in control animals was not completely achieved. CONCLUSIONS: These data indicate that moderate anemia significantly reduces the efficacy of radiotherapy. Prevention of anemia with rHuEPO partially restores the radiosensitivity of xenografted glioblastomas to fractionated irradiation.


Assuntos
Anemia/prevenção & controle , Neoplasias Encefálicas/radioterapia , Eritropoetina/uso terapêutico , Glioblastoma/radioterapia , Tolerância a Radiação , Anemia/complicações , Anemia/etiologia , Animais , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Hipóxia Celular , Linhagem Celular Tumoral , Fracionamento da Dose de Radiação , Eritropoetina/administração & dosagem , Eritropoetina/farmacologia , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Tolerância a Radiação/efeitos dos fármacos , Dosagem Radioterapêutica , Proteínas Recombinantes , Fatores de Tempo , Transplante Heterólogo , Irradiação Corporal Total
10.
Strahlenther Onkol ; 179(9): 626-32, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14628129

RESUMO

PURPOSE: To analyze the long-term results following whole brain radiotherapy (WBRT) with sequential intrathecal (i.th.) cytosine arabinoside (Ara-C) +/- intravenous (i.v.) Ara-C in patients with primary central nervous system lymphoma (PCNSL). PATIENTS AND METHODS: 14 patients were treated between July 1987 and August 1995. All had sporadic PCNSL with proven histology of high-grade CNS lymphoma (twelve diffuse large-cell B-lymphomas, one lymphoblastic lymphoma, one large T-cell lymphoma). Patients were treated with two to four cycles of induction chemotherapy (40 mg/m2 Ara-C i.th.), four patients received additional Ara-C i.v. (150 mg/m2, d1-4). WBRT was administered using 1.8-Gy fractions. Intrathecal chemotherapy was planned afterwards in 4-week intervals for 6 months. Posttreatment neurocognitive evaluations were performed in two long-term survivors. RESULTS: Two of four patients who received i.v. and i.th. induction chemotherapy showed progressive disease, and irradiation was started immediately. Six of 14 patients received 50.4 Gy WBRT, four patients had WBRT up to 39.6 Gy followed by a 10.8-Gy boost. Five patients died early during therapy either due to a decline of the general medical condition or progressive disease. Median survival was 41 months (95% confidence interval: 6-79 months), survival at 3 and 5 years was 59% and 42%, respectively. Six patients survived for 3 years, two younger patients are still alive (> 12 years). They show only slightly impaired neurocognitive functions without clinical relevance. CONCLUSION: This WBRT-based protocol with i.th. meningeal prophylaxis using Ara-C +/- i.v. Ara-C yields substantial long-term survival with moderate toxicity. The value of i.v. chemotherapy is currently being investigated in prospective studies.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/terapia , Citarabina/uso terapêutico , Linfoma/mortalidade , Linfoma/terapia , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Causas de Morte , Terapia Combinada , Intervalos de Confiança , Citarabina/administração & dosagem , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Injeções Espinhais , Linfoma/tratamento farmacológico , Linfoma/radioterapia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/mortalidade , Linfoma de Células B/radioterapia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/radioterapia , Linfoma Anaplásico de Células Grandes/tratamento farmacológico , Linfoma Anaplásico de Células Grandes/mortalidade , Linfoma Anaplásico de Células Grandes/radioterapia , Linfoma de Células T/tratamento farmacológico , Linfoma de Células T/mortalidade , Linfoma de Células T/radioterapia , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/radioterapia , Dosagem Radioterapêutica , Análise de Sobrevida , Fatores de Tempo
11.
Int J Cancer ; 106(5): 723-8, 2003 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-12866032

RESUMO

In spite of aggressive therapy, children suffering from neuroblastoma have a poor prognosis. Therapeutic failure is most often observed in neuroblastomas with unfavorable features, including amplification/over-expression of the N-myc oncogene, rapid growth, effective angiogenesis and/or the tendency to metastasize. Here, we have used cultured human neuroblastoma cells with such features and we have examined whether antiangiogenic agents alone or in combination with tumor irradiation inhibit their angiogenesis and growth in vivo. We report that antiangiogenic agents (arginine deiminase, SU5416 and DC101) inhibit in vivo growth of neuroblastomas with unfavorable properties and that these effects are potentiated by simultaneous irradiation. Combination of either agent with irradiation leads to a reduction in the absolute number of tumor vessels and of perfused tumor vessels. Combination of arginine deiminase or DC101 with irradiation does not increase tumor hypoxia. Our data demonstrate for the first time that arginine deiminase suppresses the growth of unfavorable experimental neuroblastomas and that this effect is potentiated by irradiation. We suggest that antiangiogenesis alone or in combination with established therapeutic regimen may improve the outcome of unfavorable neuroblastomas in a clinical setting.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Hidrolases/uso terapêutico , Neuroblastoma/patologia , Animais , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Hipóxia Celular , Terapia Combinada , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/patologia , Endotélio Vascular/efeitos da radiação , Regulação Neoplásica da Expressão Gênica , Humanos , Indóis/uso terapêutico , Camundongos , Camundongos Nus , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirróis/uso terapêutico , Células Tumorais Cultivadas , Irradiação Corporal Total , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Int J Radiat Oncol Biol Phys ; 55(5): 1358-62, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12654448

RESUMO

PURPOSE: The effect of recombinant human erythropoietin (rhEPO) on the radiosensitivity of human tumor xenografts growing in anemic and nonanemic nude mice was studied. METHODS AND MATERIALS: Anemia was induced by total body irradiation ([TBI], 2 x 4 Gy) of mice before tumor implantation into the subcutis of the hind leg. The development of anemia was prevented by rhEPO (750 U/kg s.c.) given 3 times weekly starting 2 weeks before TBI. Fourteen days after fractionated TBI (tumor volume of approx. 40 mm(3)), single-dose irradiation of the tumor with varying doses was performed so that in full dose-response relationship for the probability of tumor cure was obtained. RESULTS: Radiation-induced anemia (hemoglobin concentration [cHb] = 9.9 g/dl) led to a reduced radiosensitivity compared to controls [49.4 vs. 40.1 Gy radiation dose to control 50% of the tumors (TCD50)]. Upon rhEPO treatment for anemia prevention (cHb = 13.3 g/dl), the TCD50 was 39.8 Gy, illustrating restored radiosensitivity compared to anemic mice. CONCLUSION: These data provide further experimental evidence for restored radiosensitivity upon prevention of anemia with rhEPO.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/farmacologia , Lesões Experimentais por Radiação/tratamento farmacológico , Tolerância a Radiação/efeitos dos fármacos , Sarcoma/radioterapia , Irradiação Corporal Total , Anemia/complicações , Anemia/metabolismo , Animais , Hipóxia Celular , Fracionamento da Dose de Radiação , Avaliação Pré-Clínica de Medicamentos , Eritropoetina/uso terapêutico , Hemoglobinas/análise , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Lesões Experimentais por Radiação/complicações , Lesões Experimentais por Radiação/metabolismo , Proteínas Recombinantes , Sarcoma/complicações , Sarcoma/metabolismo , Transplante Heterólogo , Irradiação Corporal Total/efeitos adversos
13.
Cancer Gene Ther ; 10(12): 926-34, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14712319

RESUMO

Lung cancer is difficult to control locally by radiotherapy and is known to have frequently p53 mutations. Previous results have shown that non-small-cell lung cancer (NSCLC) cell lines with nonfunctional p53 have a higher fraction of radiation-induced apoptosis and that apoptosis follows after the release from the G2/M arrest. The aim of the present work was to study whether inhibition of the p53 response in NSCLC cell lines can modulate the G2/M arrest and the induction of apoptosis after ionizing radiation. Antisense oligodeoxynucleotides (As-ODNs) were used to inhibit the p53 response in the cell lines H460 and A549 with functional p53. In addition, H661 with nonfunctional p53 was used. The results have shown that As-ODNs targeting mRNA of p53 and p21 downregulate radiation-induced expression of p53 and p21(WAF1/CIP1). Delayed apoptosis (35.7+/-4.2% in H460, 1.2+/-0.4% in A549 and 72.2+/-6.5% in H661) was observed after cell cycle progression beyond the G2 block, either in the late G2 phase of the same cell cycle being irradiated (H661) or in the G1 phase of the subsequent cell cycle (H460, A549). As-p53 significantly decreased the fraction of G2/M-arrested cells in H460 cells and increased radiation-induced apoptosis at 96 hours by 17.9+/-8.5 and 9.1+/-3.3% to 53.6+/-7.4 and 10.8+/-2.9% in H460 and A549 cells (P<.01), respectively, but had no effect in H661 cells with nonfunctional p53. In addition, As-p21 decreased the fraction of G2-arrested A549 and H460 cells and increased apoptosis by 23.8+/-5.2 and 31.6+/-7.3% to 59.4+/-3.1 and 32.8+/-7.3%, respectively (P<.01). In conclusion, these data show that radiation-induced G2 arrest is decreased in NSCLC cells and radiation-induced apoptosis is increased when p53-responsive pathways are blocked via As-ODN targeting p53 or p21(WAF1/CIP1) mRNA. In view of the fact that p53 and p21 As-ODN had similar effects on radiation-induced apoptosis normalized by their ability to inhibit radiation-induced p21 expression, we concluded that p21 is an important trigger of late ionizing radiation-induced apoptosis.


Assuntos
Apoptose , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular , Ciclinas/genética , Genes p53/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Oligonucleotídeos Antissenso/genética , Apoptose/genética , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21 , Humanos , RNA Mensageiro , Radiação Ionizante
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