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1.
Radiat Oncol ; 17(1): 79, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440003

RESUMO

BACKGROUND: Inherent resistance to radio/chemotherapy is one of the major reasons for early recurrence, treatment failure, and dismal prognosis of glioblastoma. Thus, the identification of resistance driving regulators as prognostic and/or predictive markers as well as potential vulnerabilities for combined modality treatment approaches is of pivotal importance. METHODS: We performed an integrative analysis of treatment resistance and DNA damage response regulator expression in a panel of human glioblastoma cell lines. mRNA expression levels of 38 DNA damage response regulators were analyzed by qRT-PCR. Inherent resistance to radiotherapy (single-shot and fractionated mode) and/or temozolomide treatment was assessed by clonogenic survival assays. Resistance scores were extracted by dimensionality reduction and subjected to correlation analyses with the mRNA expression data. Top-hit candidates with positive correlation coefficients were validated by pharmacological inhibition in clonogenic survival assays and DNA repair analyses via residual γH2AX/53BP1-foci staining. RESULTS: Inherent resistance to single-shot and similarly also to fractionated radiotherapy showed strong positive correlations with mRNA expression levels of known vulnerabilities of GBM, including PARP1, NBN, and BLM, as well as ATR and LIG4-two so far underestimated targets. Inhibition of ATR by AZD-6738 resulted in robust and dose-dependent radiosensitization of glioblastoma cells, whereas LIG4 inhibition by L189 had no noticeable impact. Resistance against temozolomide showed strong positive correlation with mRNA expression levels of MGMT as to be expected. Interestingly, it also correlated with mRNA expression levels of ATM, suggesting a potential role of ATM in the context of temozolomide resistance in glioblastoma cells. ATM inhibition exhibited slight sensitization effects towards temozolomide treatment in MGMT low expressing glioblastoma cells, thus encouraging further characterization. CONCLUSIONS: Here, we describe a systematic approach integrating clonogenic survival data with mRNA expression data of DNA damage response regulators in human glioblastoma cell lines to identify markers of inherent therapy resistance and potential vulnerabilities for targeted sensitization. Our results provide proof-of-concept for the feasibility of this approach, including its limitations. We consider this strategy to be adaptable to other cancer entities as well as other molecular data qualities, and its upscaling potential in terms of model systems and observational data levels deserves further investigation.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/terapia , Linhagem Celular Tumoral , Quimiorradioterapia , Terapia Combinada , Metilases de Modificação do DNA/genética , Metilases de Modificação do DNA/metabolismo , Metilases de Modificação do DNA/uso terapêutico , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Enzimas Reparadoras do DNA/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/terapia , Humanos , RNA Mensageiro/genética , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Transcriptoma
2.
Psychooncology ; 31(5): 770-778, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34894364

RESUMO

OBJECTIVE: To improve allocation of psychosocial care and to provide patient-oriented support offers, identification of determinants of elevated distress is needed. So far, there is a lack of evidence investigating the interplay between individual disposition and current clinical and psychosocial determinants of distress in the inpatient setting. METHODS: In this cross-sectional study, we investigated 879 inpatients with different cancer sites treated in a German Comprehensive Cancer Center. Assessment of determinants of elevated distress included sociodemographic, clinical and psychosocial characteristics as well as dimensions of personality. Multiple linear regression was applied to identify determinants of psychosocial distress. RESULTS: Mean age of the patients was M = 61.9 (SD = 11.8), 48.1% were women. In the multiple linear regression model younger age (ß = -0.061, p = 0.033), higher neuroticism (ß = 0.178, p = <0.001), having metastases (ß = 0.091, p = 0.002), being in a worse physical condition (ß = 0.380, p = <0.001), depressive symptoms (ß = 0.270, p = <0.001), not feeling well informed about psychological support (ß = 0.054, p = 0.046) and previous uptake of psychological treatment (ß = 0.067, p = 0.020) showed significant associations with higher psychosocial distress. The adjusted R2 of the overall model was 0.464. CONCLUSION: Controlling for sociodemographic characteristics and dispositional vulnerability, that is neuroticism, current clinical and psychosocial characteristics were still associated with hospitalized patients' psychosocial distress. Psycho-oncologists should address both, the more transient emotional responses, such as depressive symptoms, as well as more enduring patient characteristics, like neuroticism.


Assuntos
Neoplasias , Estudos Transversais , Feminino , Humanos , Pacientes Internados/psicologia , Masculino , Neoplasias/psicologia , Neuroticismo , Personalidade , Estresse Psicológico/psicologia
3.
Cell Death Dis ; 12(12): 1162, 2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34911941

RESUMO

Resistance against radio(chemo)therapy-induced cell death is a major determinant of oncological treatment failure and remains a perpetual clinical challenge. The underlying mechanisms are manifold and demand for comprehensive, cancer entity- and subtype-specific examination. In the present study, resistance against radiotherapy was systematically assessed in a panel of human head-and-neck squamous cell carcinoma (HNSCC) cell lines and xenotransplants derived thereof with the overarching aim to extract master regulators and potential candidates for mechanism-based pharmacological targeting. Clonogenic survival data were integrated with molecular and functional data on DNA damage repair and different cell fate decisions. A positive correlation between radioresistance and early induction of HNSCC cell senescence accompanied by NF-κB-dependent production of distinct senescence-associated cytokines, particularly ligands of the CXCR2 chemokine receptor, was identified. Time-lapse microscopy and medium transfer experiments disclosed the non-cell autonomous, paracrine nature of these mechanisms, and pharmacological interference with senescence-associated cytokine production by the NF-κB inhibitor metformin significantly improved radiotherapeutic performance in vitro and in vivo. With regard to clinical relevance, retrospective analyses of TCGA HNSCC data and an in-house HNSCC cohort revealed that elevated expression of CXCR2 and/or its ligands are associated with impaired treatment outcome. Collectively, our study identifies radiation-induced tumor cell senescence and the NF-κB-dependent production of distinct senescence-associated cytokines as critical drivers of radioresistance in HNSCC whose therapeutic targeting in the context of multi-modality treatment approaches should be further examined and may be of particular interest for the subgroup of patients with elevated expression of the CXCR2/ligand axis.


Assuntos
Senescência Celular , Neoplasias de Cabeça e Pescoço , Tolerância a Radiação , Receptores de Interleucina-8B , Carcinoma de Células Escamosas de Cabeça e Pescoço , Linhagem Celular Tumoral , Citocinas , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Ligantes , NF-kappa B , Receptores de Interleucina-8B/metabolismo , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/radioterapia
4.
Gastroenterology ; 161(3): 996-1010.e1, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34097885

RESUMO

BACKGROUNDS & AIMS: Fluoropyrimidine c (5-fluorouracil [5FU]) increasingly represents the chemotherapeutic backbone for neoadjuvant, adjuvant, and palliative treatment of pancreatic ductal adenocarcinoma (PDAC). Even in combination with other agents, 5FU efficacy remains transient and limited. One explanation for the inadequate response is insufficient and nonspecific delivery of 5FU to the tumor. METHODS: We designed, generated, and characterized 5FU-incorporated systematic evolution of ligands by exponential enrichment (SELEX)-selected epidermal growth factor receptor (EGFR)-targeted aptamers for tumor-specific delivery of 5FU to PDAC cells and tested their therapeutic efficacy in vitro and in vivo. RESULTS: 5FU-EGFR aptamers reduced proliferation in a concentration-dependent manner in mouse and human pancreatic cancer cell lines. Time-lapsed live imaging showed EGFR-specific uptake of aptamers via clathrin-dependent endocytosis. The 5FU-aptamer treatment was equally effective in 5FU-sensitive and 5FU-refractory PDAC cell lines. Biweekly treatment with 5FU-EGFR aptamers reduced tumor burden in a syngeneic orthotopic transplantation model of PDAC, in an autochthonously growing genetically engineered PDAC model (LSL-KrasG12D/+;LSL-Trp53flox/+;Ptf1a-Cre [KPC]), in an orthotopic cell line-derived xenograft model using human PDAC cells in athymic mice (CDX; Crl:NU-Foxn1nu), and in patient-derived organoids. Tumor growth was significantly attenuated during 5FU-EGFR aptamer treatment in the course of follow-up. CONCLUSIONS: Tumor-specific targeted delivery of 5FU using EGFR aptamers as the carrier achieved high target specificity; overcame 5FU resistance; and proved to be effective in a syngeneic orthotopic transplantation model, in KPC mice, in a CDX model, and in patient-derived organoids and, therefore, represents a promising backbone for pancreatic cancer chemotherapy in patients. Furthermore, our approach has the potential to target virtually any cancer entity sensitive to 5FU treatment by incorporating 5FU into cancer cell-targeting aptamers as the delivery platform.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Aptâmeros de Nucleotídeos/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Sistemas de Liberação de Medicamentos , Receptores ErbB/metabolismo , Fluoruracila/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Animais , Antimetabólitos Antineoplásicos/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Endocitose , Receptores ErbB/genética , Feminino , Fluoruracila/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Organoides , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Técnica de Seleção de Aptâmeros , Carga Tumoral/efeitos dos fármacos , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
J Med Internet Res ; 22(4): e16533, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32077858

RESUMO

BACKGROUND: Many comprehensive cancer centers incorporate tumor documentation software supplying structured information from the associated centers' oncology patients for internal and external audit purposes. However, much of the documentation data included in these systems often remain unused and unknown by most of the clinicians at the sites. OBJECTIVE: To improve access to such data for analytical purposes, a prerollout of an analysis layer based on the business intelligence software QlikView was implemented. This software allows for the real-time analysis and inspection of oncology-related data. The system is meant to increase access to the data while simultaneously providing tools for user-friendly real-time analytics. METHODS: The system combines in-memory capabilities (based on QlikView software) with innovative techniques that compress the complexity of the data, consequently improving its readability as well as its accessibility for designated end users. Aside from the technical and conceptual components, the software's implementation necessitated a complex system of permission and governance. RESULTS: A continuously running system including daily updates with a user-friendly Web interface and real-time usage was established. This paper introduces its main components and major design ideas. A commented video summarizing and presenting the work can be found within the Multimedia Appendix. CONCLUSIONS: The system has been well-received by a focus group of physicians within an initial prerollout. Aside from improving data transparency, the system's main benefits are its quality and process control capabilities, knowledge discovery, and hypothesis generation. Limitations such as run time, governance, or misinterpretation of data are considered.


Assuntos
Oncologia/métodos , Humanos , Internet , Software/normas
6.
Med Phys ; 45(11): 4916-4926, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30199101

RESUMO

PURPOSE: To demonstrate a proof-of-concept for fast cone-beam CT (CBCT) intensity correction in projection space by the use of deep learning. METHODS: The CBCT scans and corresponding projections were acquired from 30 prostate cancer patients. Reference shading correction was performed using a validated method (CBCT cor ), which estimates scatter and other low-frequency deviations in the measured CBCT projections on the basis of a prior CT image obtained from warping the planning CT to the CBCT. A convolutional neural network (ScatterNet) was designed, consisting of an attenuation conversion stage followed by a shading correction stage using a UNet-like architecture. The combined network was trained in 2D, utilizing pairs of measured and corrected projections of the reference method, in order to perform shading correction in projection space before reconstruction. The number of patients used for training, testing, and evaluation was 15, 7, and 8, respectively. The reconstructed CBCT ScatterNet was compared to CBCT cor in terms of mean and absolute errors (ME and MAE) for the eight evaluation patients (not included in the network training). Volumetric modulated arc photon therapy (VMAT) and intensity-modulated proton therapy (IMPT) plans were generated on CBCT cor . Dose was recalculated on CBCT ScatterNet to evaluate its dosimetric accuracy. Single-field uniform dose proton plans were utilized for proton range comparison of CBCT ScatterNet and CBCT cor . RESULTS: The CBCT ScatterNet showed no cupping artifacts and a considerably smaller MAE and ME with respect to CBCT cor than the uncorrected CBCT (on average 144 Hounsfield units (HU) vs 46 HU for MAE and 138 HU vs -3 HU for ME). The pass-rates using a 2% dose-difference criterion at 50% dose cut-off, were close to 100% for the VMAT plans of all patients when comparing CBCT ScatterNet to CBCT cor . For IMPT plans pass-rates were clearly lower, ranging from 15% to 81%. Proton range differences of up to 5 mm occurred. CONCLUSIONS: Using a deep convolutional neural network for CBCT intensity correction was shown to be feasible in the pelvic region for the first time. Dose calculation accuracy on CBCT ScatterNet was high for VMAT, but unsatisfactory for IMPT. With respect to the reference technique (CBCT cor ), the neural network enabled a considerable increase in speed for intensity correction and might eventually allow for on-the-fly shading correction during CBCT acquisition.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Radiometria
7.
Radiat Oncol ; 13(1): 123, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970111

RESUMO

BACKGROUND: Postoperative (chemo) radiation improves tumor control and survival in high-risk patients with head and neck squamous cell carcinoma based on established risk factors. The clinical cooperation group "Personalized Radiotherapy in Head and Neck Cancer" focuses on the identification and validation of new biomarkers, which are aimed at eventually stratifying and personalizing the therapy concept. Hence, we reviewed all patients with head and neck squamous cell carcinoma of the oral cavity, oropharynx, hypopharynx, or larynx, treated with postoperative (chemo) radiation from 06/2008 until 06/2015 at the Department of Radiation Oncology in the University Hospital, LMU Munich. Here we report the clinical results of the cohort, laying the foundation for further research within the framework of a clinical cooperation group. METHODS: Patient data were retrospectively (until 2013) and prospectively (from 2013) collected and analyzed for outcome and treatment failures with regard to previously described and established risk factors. RESULTS: We identified 302 patients (median follow-up 45 months, average age 60.7 years), having received postoperative (chemo)radiation (median 64 Gy). Chemotherapy was added in 58% of cases, mostly Cisplatin/5- Fluorouracil in concordance with the ARO 96-3 study. The 3-year overall survival, local, locoregional and distant failure estimates were 70.5, 9.7, 12.2 and 13.5%, respectively. Human papillomavirus-associated oropharyngeal cancer was associated with a significant improved overall survival, locoregional, distant and overall tumor control rates in multivariate analysis. Additionally, in multivariate analysis, for local failure, resection status and perineural invasion, for locoregional and distant failure extracapsular extension and for overall survival the presence of nodal disease were significant adverse factors. Moreover, 138 patients have been treated in concordance with the ARO 96-3 protocol, corroborating the results of this study. CONCLUSIONS: Our cohort represents a large unselected cohort of patients with head and neck squamous cell carcinoma treated with postoperative (chemo)radiation. Tumor control rates and survival rates are consistent with the results of previously reported data.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Neoplasias Laríngeas/terapia , Neoplasias Bucais/terapia , Neoplasias Faríngeas/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cisplatino/administração & dosagem , Terapia Combinada , Células Epiteliais , Feminino , Fluoruracila/administração & dosagem , Alemanha , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Cuidados Pós-Operatórios , Estudos Prospectivos , Estudos Retrospectivos
8.
JAMA Oncol ; 4(4): 483-492, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29450452

RESUMO

IMPORTANCE: Patients with soft tissue sarcoma are at risk for local recurrence and distant metastases despite optimal local treatment. Preoperative anthracycline plus ifosfamide chemotherapy improves outcome in common histological subtypes. OBJECTIVE: To analyze whether the previously reported improvement in local progression-free survival by adding regional hyperthermia to neoadjuvant chemotherapy translates into improved survival. DESIGN, SETTING, AND PARTICIPANTS: Open-label, phase 3 randomized clinical trial to evaluate the efficacy and toxic effects of neoadjuvant chemotherapy plus regional hyperthermia. Adult patients (age ≥18 years) with localized soft tissue sarcoma (tumor ≥5 cm, French Federation Nationale des Centers de Lutte Contre le Cancer [FNCLCC] grade 2 or 3, deep) were accrued across 9 centers (6, Germany; 1, Norway; 1, Austria; 1, United States) from July 1997 to November 2006. Follow-up ended December 2014. INTERVENTIONS: After stratification for tumor presentation and site, patients were randomly assigned to either neoadjuvant chemotherapy consisting of doxorubicin, ifosfamide, and etoposide alone, or combined with regional hyperthermia. MAIN OUTCOMES AND MEASURES: The primary end point was local progression-free survival. Secondary end points included treatment safety and survival, with survival defined from date of randomization to death due to disease or treatment. Patients lost to follow-up were censored at the date of their last follow-up. RESULTS: A total of 341 patients were randomized, and 329 (median [range] age, 51 [18-70] years; 147 women, 182 men) were eligible for the intention-to-treat analysis. By December 2014, 220 patients (67%; 95% CI, 62%-72%) had experienced disease relapse, and 188 (57%; 95% CI, 52%-62%) had died. Median follow-up was 11.3 years. Compared with neoadjuvant chemotherapy alone, adding regional hyperthermia improved local progression-free survival (hazard ratio [HR], 0.65; 95% CI, 0.49-0.86; P = .002). Patients randomized to chemotherapy plus hyperthermia had prolonged survival rates compared with those randomized to neoadjuvant chemotherapy alone (HR, 0.73; 95% CI, 0.54-0.98; P = .04) with 5-year survival of 62.7% (95% CI, 55.2%-70.1%) vs 51.3% (95% CI, 43.7%-59.0%), respectively, and 10-year survival of 52.6% (95% CI, 44.7%-60.6%) vs 42.7% (95% CI, 35.0%-50.4%). CONCLUSIONS AND RELEVANCE: Among patients with localized high-risk soft tissue sarcoma the addition of regional hyperthermia to neoadjuvant chemotherapy resulted in increased survival, as well as local progression-free survival. For patients who are candidates for neoadjuvant treatment, adding regional hyperthermia may be warranted. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00003052.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hipertermia Induzida/métodos , Sarcoma/terapia , Neoplasias de Tecidos Moles/terapia , Adolescente , Adulto , Idoso , Terapia Combinada , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Intervalo Livre de Progressão , Fatores de Risco , Sarcoma/mortalidade , Sarcoma/patologia , Neoplasias de Tecidos Moles/mortalidade , Neoplasias de Tecidos Moles/patologia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
9.
Strahlenther Onkol ; 193(4): 324-331, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28124093

RESUMO

BACKGROUND: The optimal sequence of mastectomy with immediate breast reconstruction (IBR) and radiotherapy (RT) for the treatment of locally advanced breast cancer (LABC) is still under debate. Increased rates of postoperative complications are described following postmastectomy RT. Neoadjuvant RT aims to improve the aesthetic results and simplify the reconstructive pathway. PATIENTS: A total of 22 patients diagnosed with LABC and treated with neoadjuvant RT followed by mastectomy and IBR between 04/2012 and 03/2015 were retrospectively analyzed. RT consisted of external beam RT to the breast and the regional lymphatics, if indicated. Both implant-based and autologous tissue-transfer reconstruction techniques were used. RESULTS: At the time of RT, 10 patients had no prior surgery and 12 patients had previously undergone breast-conserving surgery (BCS) with positive resection margins without the possibility to perform a second BCS. Additional neoadjuvant chemotherapy was administered in 18 patients prior to RT. A complete pathological response was achieved in 55.0% of patients. The 2­year overall survival rate was 89.3%, the 2­year disease-free-survival 79.8% and the local-recurrence-free survival was 95.2%. The cosmetic result was excellent or good in 66% of the patients treated with upfront mastectomy and 37% of the patients who had previously undergone BCS. Among patients who received implant-based IBR, 4 patients developed serious wound-healing problems with implant loss. The most satisfactory results were achieved with autologous tissue reconstruction. CONCLUSION: A sequential neoadjuvant chemo-/radiotherapy to allow IBR following mastectomy in selected cases of LABC seems feasible and can be safely attempted. Careful patient selection, close monitoring, and continuous patient support is mandatory to ensure compliance in this treatment strategy.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/terapia , Mamoplastia/métodos , Mastectomia/métodos , Radioterapia Conformacional/métodos , Adulto , Idoso , Neoplasias da Mama/psicologia , Terapia Combinada/métodos , Procedimentos Clínicos/organização & administração , Feminino , Humanos , Mamoplastia/psicologia , Mastectomia/psicologia , Pessoa de Meia-Idade , Satisfação do Paciente , Dosagem Radioterapêutica , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/psicologia , Radioterapia Conformacional/psicologia , Resultado do Tratamento
10.
Strahlenther Onkol ; 192(11): 780-788, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27349709

RESUMO

BACKGROUND: Outcome and toxicity profiles of salvage stereotactic ablative radiation strategies for recurrent pre-irradiated brain metastases are poorly defined. This study compared risk-benefit profiles of upfront and salvage iodine-125 brachytherapy (SBT) for small brain metastases. As the applied SBT treatment algorithm required histologic proof of metastatic brain disease in all patients, we additionally aimed to elucidate the value of biopsy before SBT. PATIENTS AND METHODS: Patients with small untreated (n = 20) or pre-irradiated (n =28) suspected metastases intended for upfront or salvage SBT, respectively, were consecutively included. Temporary iodine-125 implants were used (median reference dose: 50 Gy, median dose rate: 15 cGy/h). Cumulative biologically effective doses (BED) were calculated and used for risk assessment. Treatment toxicity was classified according to Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer (RTOG/EORTC) criteria. RESULTS: Upfront SBT was initiated in 20 patients and salvage SBT in 23. In 5 patients, salvage SBT was withheld because of proven radiation-induced lesions. Treatment groups exhibited similar epidemiologic data except for tumor size (which was slightly smaller in the salvage group). One-year local/distant tumor control rates after upfront and salvage SBT were similar (94 %/65 % vs. 87 %/57 %, p = 0.45, respectively). Grade I/II toxicity was suffered by 2 patients after salvage SBT (cumulative BED: 192.1 Gy3 and 249.6 Gy3). No toxicity-related risk factors were identified. CONCLUSION: SBT combines diagnostic yield with effective treatment in selected patients. The low toxicity rate in the salvage group points to protective radiobiologic characteristics of continuous low-dose rate irradiation. Upfront and salvage SBT are similarly effective and safe. Histologic reevaluation should be reconsidered after previous radiotherapy to avoid under- or overtreatment.


Assuntos
Braquiterapia/efeitos adversos , Lesões Encefálicas/prevenção & controle , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Lesões por Radiação/prevenção & controle , Lesões Encefálicas/etiologia , Neoplasias Encefálicas/patologia , Feminino , Humanos , Radioisótopos do Iodo/efeitos adversos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Lesões por Radiação/etiologia , Compostos Radiofarmacêuticos/efeitos adversos , Compostos Radiofarmacêuticos/uso terapêutico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Adjuvante , Estudos Retrospectivos , Terapia de Salvação/efeitos adversos , Terapia de Salvação/métodos , Resultado do Tratamento
11.
Int J Cancer ; 139(2): 467-79, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-26933761

RESUMO

The tetrahydroisoquinoline trabectedin is a marine compound with approved activity against human soft-tissue sarcoma. It exerts antiproliferative activity mainly by specific binding to the DNA and inducing DNA double-strand breaks (DSB). As homologous recombination repair (HRR)-deficient tumors are more susceptible to trabectedin, hyperthermia-mediated on-demand induction of HRR deficiency represents a novel and promising strategy to boost trabectedin treatment. For the first time, we demonstrate enhancement of trabectedin effectiveness in human sarcoma cell lines by heat and characterize cellular events and molecular mechanisms related to heat-induced effects. Hyperthermic temperatures (41.8 or 43°C) enhanced significantly trabectedin-related clonogenic cell death and G2/M cell cycle arrest followed by cell type-dependent induction of apoptosis or senescence. Heat combination increased accumulation of γH2AX foci as key marker of DSBs. Expression of BRCA2 protein, an integral protein of the HRR machinery, was significantly decreased by heat. Consequently, recruitment of downstream RAD51 to γH2AX-positive repair foci was almost abolished indicating relevant impairment of HRR by heat. Accordingly, enhancement of trabectedin effectiveness was significantly augmented in BRCA2-proficient cells by hyperthermia and alleviated in BRCA2 knockout or siRNA-transfected BRCA2 knockdown cells. In peripheral blood mononuclear cells isolated from sarcoma patients, increased numbers of nuclear γH2AX foci were detected after systemic treatment with trabectedin and hyperthermia of the tumor region. The findings establish BRCA2 degradation by heat as a key factor for a novel treatment strategy that allows targeted chemosensitization to trabectedin and other DNA damaging antitumor drugs by on-demand induction of HRR deficiency.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Proteína BRCA2/metabolismo , Dioxóis/farmacologia , Hipertermia Induzida , Reparo de DNA por Recombinação/efeitos dos fármacos , Reparo de DNA por Recombinação/efeitos da radiação , Tetra-Hidroisoquinolinas/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Histonas/metabolismo , Humanos , Modelos Biológicos , Ligação Proteica , Transporte Proteico , Proteólise/efeitos dos fármacos , Proteólise/efeitos da radiação , Rad51 Recombinase/metabolismo , Sarcoma/metabolismo , Sarcoma/patologia , Sarcoma/terapia , Trabectedina
12.
Cancer Lett ; 368(2): 209-29, 2015 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25754814

RESUMO

Radiotherapy represents an essential treatment option for the majority of cancer patients in different stages of their disease. Physical achievements of the recent years led to the implementation of high precision treatment planning procedures, and image-guided dose delivery is current state of the art. Yet, radiotherapy still faces several limitations with cancer intrinsic radioresistance being a key driver of therapeutic failure. Accordingly, the mechanisms orchestrating radioresistance and their therapeutic targeting by combined modality approaches are in the center of attention of numerous radiation oncologists. In the present review, we summarize and discuss therapeutic approaches that exploit the heat shock response, either by hyperthermia or by pharmacological heat shock protein inhibition, in combination with radiotherapy. These strategies appear particularly promising, since they sensitize cancer cells to irradiation-induced cell death and at the same time have proven the potential to promote systemic anti-tumor immune mechanisms, which may target not only locally surviving tumor cells, but also distant out-of-field metastases.


Assuntos
Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Resposta ao Choque Térmico/efeitos da radiação , Hipertermia Induzida/métodos , Neoplasias/imunologia , Neoplasias/radioterapia , Animais , Morte Celular/imunologia , Morte Celular/efeitos da radiação , Terapia Combinada , Proteínas de Choque Térmico HSP90/imunologia , Proteínas de Choque Térmico/imunologia , Resposta ao Choque Térmico/imunologia , Humanos
13.
Radiother Oncol ; 104(1): 78-82, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22673727

RESUMO

BACKGROUND AND PURPOSE: The aim of the present study was to evaluate factors predicting the recurrence pattern determined by [(18)F]FET-PET imaging in patients with newly diagnosed glioblastoma after combined radio-chemotherapy treated according to the EORTC/NCIC trial. MATERIAL AND METHODS: Seventy-nine patients with newly diagnosed GBM treated with radiotherapy plus temozolomide (75 mg/m(2)/d) followed by adjuvant cyclic (5/28 days) temozolomide (150-200 mg/m(2)) were retrospectively analysed. Recurrence patterns were assessed by means of positron-emission-tomography with [(18)F]FET and additional MRI; in 54 patients MGMT methylation status was evaluated. RESULTS: Whilst 49.4% of the patients had an in-field recurrence, 12.6% an ex-field recurrence and 3.8% a recurrence at the field margin, 34.2% of the patients did not relapse during follow-up (median 595 days). Considering all patients included in this study, 41.5% (12/29) of the MGMT methylated population had no relapse, 37.9% (11/29) had an in-field-recurrence and 20.7% (6/29) an ex-field/marginal recurrence, whilst 28.0% (7/25) of the MGMT unmethylated population had no relapse, 64.0% (16/25) had an in-field-recurrence and 8.0% (2/25) an ex-field/marginal recurrence (p=0.15). CONCLUSIONS: After the administration of temozolomide concomitant with and adjuvant to radiotherapy in patients with glioblastoma, the pattern determined by [(18)F]FET-PET seems to be associated with MGMT methylation status.


Assuntos
Neoplasias Encefálicas/terapia , Quimiorradioterapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/terapia , Recidiva Local de Neoplasia/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Proteínas Supressoras de Tumor/genética , Tirosina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/mortalidade , Feminino , Glioblastoma/genética , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade
16.
Oncology ; 81(5-6): 387-94, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22269965

RESUMO

OBJECTIVES: It was the aim of this study to assess our institutional experience with definitive chemoradiation (CRT) versus induction chemotherapy followed by CRT with or without surgery (C-CRT/S) in esophageal cancer. METHODS: We retrospectively analyzed 129 institutional patients with locally advanced esophageal cancer who had been treated by either CRT in analogy to the RTOG 8501 trial (n = 78) or C-CRT/S (n = 51). RESULTS: The median, 2- and 5-year overall survival (OS) of the entire collective was 17.6 months, 42 and 24%, respectively, without a significant difference between the CRT and C-CRT/S groups. In C-CRT/S patients, surgery statistically improved the locoregional control (LRC) rates (2-year LRC 73.6 vs. 21.2%; p = 0.003); however, this was translated only into a trend towards improved OS (p = 0.084). The impact of escalated radiation doses (≥60.0 vs. <60.0 Gy) on LRC was detectable only in T1-3 N0-1 M0 patients of the CRT group (2-year LRC 77.8 vs. 42.3%; p = 0.036). CONCLUSION: Definitive CRT and a trimodality approach including surgery (C-CRT/S) had a comparable outcome in this unselected patient collective. Surgery and higher radiation doses improve LRC rates in subgroups of patients, respectively, but without effect on OS.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia Adjuvante/métodos , Cisplatino/administração & dosagem , Terapia Combinada/métodos , Neoplasias Esofágicas/patologia , Feminino , Fluoruracila/administração & dosagem , Humanos , Quimioterapia de Indução/métodos , Masculino , Pessoa de Meia-Idade , Prognóstico , Doses de Radiação , Tolerância a Radiação , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
17.
Int J Radiat Oncol Biol Phys ; 69(5): 1429-35, 2007 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-17692474

RESUMO

PURPOSE: Adjuvant, 5-fluorouracil (5-FU)-based chemoradiotherapy for completely resected high-risk gastric adenocarcinoma has been shown to improve survival in a randomized Intergroup trial. However, the results still showed an unsatisfactory outcome. On the basis of previously reported results of a Phase II trial using a more aggressive, cisplatin-containing chemoradiotherapy schedule, we investigated the effects of this approach on long-term renal function. PATIENTS AND METHODS: Between December 2000 and September 2003, 27 patients were treated at Tübingen University in a Phase II multicenter trial investigating adjuvant chemoradiotherapy. The adjuvant chemoradiotherapy consisted of two cycles of adjuvant 5-FU, folinic acid, cisplatin (200 mg/m2), and paclitaxel before and after radiotherapy (45 Gy in 1.8-Gy fractions) with daily concomitant 5-FU (225 mg/m2/24 h). A dose constraint of

Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Rim/efeitos dos fármacos , Rim/efeitos da radiação , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/radioterapia , Adulto , Idoso , Análise de Variância , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Biomarcadores/sangue , Quimioterapia Adjuvante/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Creatinina/sangue , Junção Esofagogástrica , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Dosagem Radioterapêutica , Radioterapia Adjuvante/efeitos adversos
18.
Int J Radiat Oncol Biol Phys ; 67(2): 347-55, 2007 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17236960

RESUMO

PURPOSE: Irradiation of adjuvant lymph nodes in high-risk prostate cancer was shown to be associated with improved rates of biochemical nonevidence of disease in the Radiation Therapy Oncology Group trial (RTOG 94-13). To account for the highly individual lymphatic drainage pattern we tested an intensity-modulated radiation therapy (IMRT) approach based on the determination of pelvic sentinel lymph nodes (SN). METHODS AND MATERIALS: Patients with a risk of more than 15% lymph node involvement were included. For treatment planning, SN localizations were included into the pelvic clinical target volume. Dose prescriptions were 50.4 Gy to the adjuvant area and 70.0 Gy to the prostate. All treatment plans were generated using equivalent uniform dose (EUD)-based optimization algorithms and Monte Carlo dose calculations and compared with 3D conventional plans. RESULTS: A total of 25 patients were treated and 142 SN were detectable (mean: n = 5.7; range, 0-13). Most SN were found in the external iliac (35%), the internal iliac (18.3%), and the iliac commune (11.3%) regions. Using a standard CT-based planning target volume, relevant SN would have been missed in 19 of 25 patients, mostly in the presacral/perirectal area (22 SN in 12 patients). The comparison of conventional 3D plans with the respective IMRT plans revealed a clear superiority of the IMRT plans. No gastrointestinal or genitourinary acute toxicity Grade 3 or 4 (RTOG criteria) occurred. CONCLUSIONS: Distributions of SN are highly variable. Data for SN derived from single photon emission computed tomography are easily integrated into an IMRT-based treatment strategy. By using SN data the probability of a geographic miss is reduced. The use of IMRT allows sparing of normal tissue irradiation.


Assuntos
Linfonodos/patologia , Neoplasias da Próstata/radioterapia , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Colo Sigmoide/efeitos da radiação , Humanos , Metástase Linfática , Masculino , Método de Monte Carlo , Estadiamento de Neoplasias , Pelve , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia Conformacional/efeitos adversos , Radioterapia de Intensidade Modulada/efeitos adversos , Reto/efeitos da radiação , Bexiga Urinária/efeitos da radiação
19.
Int J Radiat Oncol Biol Phys ; 55(5): 1374-80, 2003 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-12654450

RESUMO

PURPOSE: The human liver is known to be a relatively radiosensitive organ that develops clinically relevant late radiation hepatitis subsequent to whole liver treatment with total doses above 30 Gy in conventional fractionation. Experimental data, as well as clinical series, have demonstrated that hyperthermia of solid tumors in addition to radiotherapy enhances tumor growth inhibition and tumor control probability. We therefore developed an experimental model for combined radiotherapy and hyperthermia of the liver in transplantable rat Morris hepatoma 3924A. METHODS AND MATERIALS: A cube of approximately 8 mm(3) was implanted subcapsularly into the middle liver lobe of 59 male syngenic ACI rats weighing approximately 180-200 g. On Day 16 after tumor implantation, irradiation of the tumor-bearing liver with either 0 Gy/25 Gy/35 Gy/45 Gy total dose in 10 fractions +/- hyperthermia (target temperature 40-42 degrees C) twice a week was initiated. Energy deposition was monitored by temperature probes in the liver and esophagus of the rats. Determination of tumor volume with magnetic resonance imaging was performed 2 to 5 weeks after the end of therapy. The tumor growth rates could be estimated for 44 rats. If the growth rate was positive (37 rats), the inverse of the growth rate was interpreted as the time to 10-fold tumor volume. Otherwise the maximum observation time was considered as a censored value in a parametric survival analysis. RESULTS: Intrahepatic temperature probes showed a temperature plateau of greater than 40 degrees C after 5 to 8 min subsequent to initiation of hyperthermia. The target temperatures could be maintained for at least 22 min > or =40 degrees C and 10 min > or =41 degrees C, respectively. Median plateau temperature in liver, esophagus, and epicutaneously was 41.2 degrees C (standard deviation [SD] 0.7 degrees C; range 38.2 to 43.3 degrees C), 40.4 degrees C (SD 1.08 degrees C; range 38.9 to 41.8 degrees C), and 40.8 degrees C (SD 0.8 degrees C; range 38.2 to 42.7 degrees C), respectively. Elevation of the temperature in the esophagus correlated with intrahepatic temperatures in the range of 39-42 degrees C, r = 0.957. The increase in time to 10-fold tumor volume for each step of irradiation dosage was by 34% (95% confidence interval [CI] 20% to 49%) without hyperthermia and by 60% (95% CI 47% to 80%) with hyperthermia (p < 0.0001). CONCLUSION: Treatment outcome after experimental percutaneous thermoradiotherapy in intrahepatically implanted Morris hepatoma 3924A was related to total dose of irradiation and concurrently administered regional hyperthermia. An increased radiosensitivity due to hyperthermia (<42 degrees C) has to be assumed.


Assuntos
Hipertermia Induzida , Neoplasias Hepáticas Experimentais/terapia , Radioterapia de Alta Energia , Animais , Temperatura Corporal , Terapia Combinada , Relação Dose-Resposta à Radiação , Hepatite/etiologia , Hepatite/prevenção & controle , Hipertermia Induzida/instrumentação , Fígado/efeitos da radiação , Circulação Hepática , Neoplasias Hepáticas Experimentais/radioterapia , Masculino , Transplante de Neoplasias , Imagens de Fantasmas , Lesões Experimentais por Radiação/etiologia , Lesões Experimentais por Radiação/prevenção & controle , Ondas de Rádio , Radioterapia de Alta Energia/efeitos adversos , Ratos , Ratos Endogâmicos ACI
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