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1.
Radiother Oncol ; 185: 109728, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37301259

RESUMO

BACKGROUND AND PURPOSE: Our study aimed to assess whether quantitative pretreatment 18F-FDG-PET/CT parameters could predict prognostic clinical outcome of recurrent NSCLC patients who may benefit from ablative reirradiation. MATERIALS AND METHODS: Forty-eight patients with recurrent NSCLC of all UICC stages who underwent ablative thoracic reirradiation were analyzed. Twenty-nine (60%) patients received immunotherapy with or without chemotherapy in addition to reirradiation. Twelve patients (25%) received reirradiation only and seven (15%) received chemotherapy and reirradiation. Pretreatment 18-FDG-PET/CT was mandatory in initial diagnosis and recurrence, based on which volumetric and intensity quantitative parameters were measured before reirradiation and their impact on overall survival, progression-free survival, and locoregional control was assessed. RESULTS: With a median follow-up time of 16.7 months, the median OS was 21.8 months (95%-CI: 16.2-27.3). On multivariate analysis, OS and PFS were significantly influenced by MTV (p < 0.001 for OS; p = 0.006 for PFS), TLG (p < 0.001 for OS; p = 0.001 for PFS) and SUL peak (p = 0.0024 for OS; p = 0.02 for PFS) of the tumor and MTV (p = 0.004 for OS; p < 0.001 for PFS) as well as TLG (p = 0.007 for OS; p = 0.015 for PFS) of the metastatic lymph nodes. SUL peak of the tumor (p = 0.05) and the MTV of the lymph nodes (p = 0.003) were only PET quantitative parameters that significantly impacted LRC. CONCLUSION: Pretreatment tumor and metastastic lymph node MTV, TLG and tumor SUL peak significantly correlated with clinical outcome in recurrent NSCLC patients treated with reirradiation-chemoimmunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Reirradiação , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Prognóstico , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/terapia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/patologia , Biomarcadores , Estudos Retrospectivos , Carga Tumoral , Compostos Radiofarmacêuticos , Glicólise
2.
Cancers (Basel) ; 15(7)2023 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-37046627

RESUMO

INTRODUCTION: Durvalumab following chemoradiotherapy (CRT) for non-small cell lung cancer stage III has become the standard of care (SoC) in the past few years. With this regimen, 5-year overall survival (OS) has risen to 43%. Therefore, adequate pulmonary function (PF) after treatment is paramount in long-term survivors. In this respect, carbon monoxide diffusing capacity (DLCO), which represents the alveolar compartment, seems to be a suitable measure for residual lung capacity. The aim of the current analysis was to correlate DLCO with pneumonitis and radiation dose. PATIENTS AND METHODS: One hundred and twelve patients with histologically confirmed NSCLC III treated between 2015/10 and 2022/03 were eligible for this study. Patients received two cycles of platinum-based induction chemotherapy followed by high-dose radiotherapy (RT). As of 2017/09, durvalumab maintenance therapy was administered for one year. The clinical endpoints were based on the thresholds jointly published by the European Respiratory Society (ERS) and the American Thoracic Society (ATS). Pre-treatment DLCO of 60% was correlated to the incidence of pneumonitis, whereas the post-treatment DLCO decline of 10% was related to radiation dose. RESULTS: Patients with a pre-treatment DLCO < 60% had a higher probability of pneumonitis (n = 98; r = 0.175; p-value 0.042), which could be reproduced in the subgroup of patients who did not receive durvalumab (n = 40; r = 0.288; p-value 0.036). In these individuals, the decline in DLCO ≥ 10% depended significantly on the size of the lung volume receiving between 45% and 65% (V65-45%) of the total radiation dose (r = 0.354; p-value = 0.020) and V20 Total Lung (r = 0.466; corrected p-value = 0.042). CONCLUSIONS: The current analysis revealed that DLCO is a predictor for clinically relevant pneumonitis and a monitoring tool for post-treatment lung function as it correlates with radiation dose. This underlines the importance of peri-treatment lung function testing.

3.
Diagnostics (Basel) ; 12(5)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35626183

RESUMO

Introduction: Curatively intended chemo-radio-immunotherapy for non-small cell lung cancer (NSCLC) stage III may lead to post-therapeutic pulmonary function (PF) impairment. We hypothesized that the decrease in global PF corresponds to the increase in tissue density in follow-up CTs. Hence, the study aim was to correlate the dynamics in radiographic alterations to carbon monoxide diffusing capacity (DLCO) and FEV1, which may contribute to a better understanding of radiation-induced lung disease. Methods: Eighty-five patients with NSCLC III were included. All of them received two cycles of platinum-based induction chemotherapy followed by high dose radiation. Thereafter, durvalumab was administered for one year in 63/85 patients (74%). Pulmonary function tests (PFTs) were performed three months and six months after completion of radiotherapy (RT) and compared to baseline. At the same time points, patients underwent diagnostic CT (dCT). These dCTs were matched to the planning CT (pCT) using RayStation® Model Based Segmentation and deformable image registration. Differential volumes defined by specific isodoses were generated to correlate them with the PFTs. Results: In general, significant correlations between PFTs and differential volumes were found in the mid-dose range, especially for the volume of the lungs receiving between 65% and 45% of the dose prescribed (V65−45%) and DLCO (p<0.01). This volume range predicted DLCO after RT (p-value 0.03) as well. In multivariate analysis, DLCO (p-value 0.040) and FEV1 (p-value 0.014) predicted pneumonitis. Conclusions: The current analysis revealed a strong relation between the dynamics of DLCO and CT morphology changes in the mid-dose range, which convincingly indicates the importance of routinely used PFTs in the context of a curative treatment approach.

4.
Biomedicines ; 10(4)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35453544

RESUMO

Gliomas are the most common intrinsic brain tumors in adults, and in accordance with their clinical behavior and patients' outcome, they are graded by the World Health Organization (WHO) classification of brain tumors. One very interesting candidate for targeted tumor therapy may be epidermal growth factor receptor (EGFR) amplification. Here, we performed an integrated comparative analysis of EGFR amplification in 34 glioma samples using standard fluorescence in situ hybridization (FISH) and Illumina EPIC Infinium Methylation Bead Chip and correlated results with molecular glioma hallmarks. We found that the EPIC analysis showed the same power of detecting EGFR amplification compared with FISH. EGFR amplification was detectable in high-grade gliomas (25%). Moreover, EGFR amplification was found to be present solely in IDH wildtype gliomas (26%) and TERT mutated gliomas (27%), occurring independently of MGMT promoter methylation status and being mutually exclusive with 1p/19q codeletion (LOH). In summary, EPIC Bead Chip analysis is a reliable tool for detecting EGFR amplification and is comparable with the standard method FISH. EGFR amplification is a phenomenon of IDH wildtype TERT mutated high-grade gliomas.

5.
Cancers (Basel) ; 14(3)2022 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-35158841

RESUMO

INTRODUCTION: Thoracic re-irradiation for recurrent lung cancer dates back four decades, when the first small series on 29 patients receiving palliative doses was published. With 5-year overall survival rates of 57% in PDL-1 positive patients after primary chemo-radio-immunotherapy, the number of patients who experience loco-regional relapse will increase in the near future. In this context, centrally recurring lung tumors pose a major treatment challenge. Hence, the aim of the current review is to compile the available evidence on curatively intended thoracic re-irradiation for this special clinical situation. METHODS: A systematic literature search according to the PRISMA guidelines was performed. A study was included when the following criteria were met: (1) 66% of the patients had NSCLC, (2) a total dose of 50 Gy in the second course and/or a biologically effective dose of at least 100 Gy in both treatment courses was administered, (3) re-irradiation was administered with modern radiation techniques, (4) 50% or more of the patients had a centrally located relapse, (5) the minimum cohort size was 30 patients. RESULTS: Of the initial 227 studies, 11 were analyzed, 1 of which was prospective. Median overall survival (OS) was 18.1 months (range 9.3-25.1), median progression free survival (PFS) was nine months (range 4.5-16), and median loco-regional control (LRC) was 12.1 months (range 6.5-20). Treatment-related mortality rates ranged from 2% to 14%. The total dose at re-irradiation correlated with both LRC (p-value = 0.012) and OS (p-value = 0.007) with a close relation between these two clinical endpoints (p-value = 0.006). The occurrence of acute toxicity grade 1 to 4 depended on the PTV size at re-irradiation (p-value = 0.033). CONCLUSION: The evidence regarding curative re-irradiation for centrally recurrent NSCLC is primarily based on scarce retrospective data, which are characterized by a high degree of heterogeneity. The OS in this clinically challenging situation is expected to be around 1.5 years after re-treatment. Patients with a good performance score, younger age, small tumors, and a longer interval to recurrence potentially benefit most from re-irradiation. In this context, prospective trials are warranted to achieve substantial advances in the field.

6.
Brain Tumor Pathol ; 39(2): 111-119, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35018523

RESUMO

Here, we report on a patient presenting with two histopathologically distinct gliomas. At the age of 42, the patient underwent initial resection of a right temporal oligodendroglioma IDH mutated 1p/19q co-deleted WHO Grade II followed by adjuvant radiochemotherapy with temozolomide. 15 months after initial diagnosis, the patient showed right hemispheric tumor progression and an additional new left frontal contrast enhancement in the subsequent imaging. A re-resection of the right-sided tumor and resection of the left frontal tumor were conducted. Neuropathological work-up showed recurrence of the right-sided oligodendroglioma with features of an anaplastic oligodendroglioma WHO Grade III, but a glioblastoma WHO grade IV for the left frontal lesion. In depth molecular profiling revealed two independent brain tumors with distinct molecular profiles of anaplastic oligodendroglioma IDH mutated 1p/19q co-deleted WHO Grade III and glioblastoma IDH wildtype WHO grade IV. This unique and rare case of a patient with two independent brain tumors revealed by in-depth molecular work-up and epigenomic profiling emphasizes the importance of integrated work-up of brain tumors including methylome profiling for advanced patient care.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Glioma , Oligodendroglioma , Astrocitoma/patologia , Biologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Cromossomos Humanos Par 1 , DNA , Glioblastoma/genética , Glioblastoma/patologia , Glioblastoma/terapia , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Metilação , Mutação , Oligodendroglioma/diagnóstico , Oligodendroglioma/genética , Oligodendroglioma/terapia
7.
Breast Cancer ; 29(2): 274-286, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34865205

RESUMO

BACKGROUND: MicroRNAs are small non-coding RNAs with pivotal regulatory functions in multiple cellular processes. Their significance as molecular predictors for breast cancer was demonstrated in the past 15 years. The aim of this study was to elucidate the role of hsa-miR-3651 for predicting of local control (LC) in early breast cancer. RESULTS: By means of high-throughput technology, hsa-miR-3651 was found to be differentially expressed between patients who experienced local relapse compared to those without (N = 23; p = 0.0035). This result could be validated in an independent cohort of 87 patients using RT-qPCR (p < 0.0005). In a second analysis step with a chip-based microarray containing 70,523 probes of potential target molecules, FERM domain protein 3 (FRMD3) was found to be the most down-regulated protein (N = 21; p = 0.0016). Computational analysis employing different prediction algorithms revealed FRMD3 as a likely downstream target of hsa-miR-3651 with an 8mer binding site between the two molecules. This could be validated in an independent patient set (N = 20, p = 0.134). CONCLUSION: The current study revealed that hsa-miR-3651 is a predictor of LC in early breast cancer via its putative target protein FRMD3. Since microRNAs interfere in multiple pathways, the results of this hypothesis generating study may contribute to the development of tailored therapies for breast cancer in the future.


Assuntos
Neoplasias da Mama , MicroRNAs , Recidiva Local de Neoplasia , Proteínas Supressoras de Tumor , Neoplasias da Mama/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Recidiva Local de Neoplasia/genética , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Supressoras de Tumor/genética
8.
Forensic Sci Med Pathol ; 18(3): 231-239, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34780010

RESUMO

A 9-year-old boy collapsed shortly after complaining of shortness of breath. Despite immediate resuscitation measures, the boy died. A few weeks earlier, he had received antibiotic treatment for respiratory infection. However, the post-mortem examination revealed an advanced tumor mass of the mediastinum with infiltration of vital structures, which was identified as a small blue round neoplasm with aspects of an extramedullary Ewing-like sarcoma by supplementary histological and immunohistochemical examinations.This dramatic clinical course of events shows that the possible presence of serious diseases should always be considered behind harmless symptoms, even in children.


Assuntos
Sarcoma de Ewing , Sarcoma , Criança , Masculino , Humanos , Sarcoma de Ewing/diagnóstico , Sarcoma de Ewing/patologia , Antibacterianos
9.
Clin Case Rep ; 9(9): e04544, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34484744

RESUMO

This case of severe phenotype-genotype mismatch brain tumor morphologically mimicking benign ganglioglioma emphasizes the urgent need for advanced molecular profiling in brain tumor diagnosis in the era of sophisticated molecular profiling.

10.
J Cancer Res Clin Oncol ; 147(8): 2271-2280, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33963441

RESUMO

PURPOSE: Gliomas are the most frequent primary brain tumors of adults. Despite intensive research, there are still no targeted therapies available. Here, we performed an integrated analysis of glioma and programmed cell death ligand 1 (PD-L1) in 90 samples including 58 glioma and 32 control brain tissues. METHODS: To identify PD-L1 expression in glioma, we performed immunohistochemical analysis of PD-L1 tumor proportion score (TPS) using the clinically valid PD-L1 22C3 antibody on 90 samples including controls and WHO grade I-IV gliomas. RESULTS: We found that PD-L1 is highly expressed in a subfraction of glioma cells. Analysis of PD-L1 levels in different glioma subtypes revealed a strong intertumoral variation of PD-L1 protein. Furthermore, we correlated PD-L1 expression with molecular glioma hallmarks such as MGMT-promoter methylation, IDH1/2 mutations, TERT promoter mutations and LOH1p/19q. CONCLUSION: In summary, we found that PD-L1 is highly expressed in a subfraction of glioma, indicating PD-L1 as a potential new marker in glioma assessment opening up novel therapeutic approaches.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , Feminino , Glioma/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Adulto Jovem
11.
Genes (Basel) ; 11(12)2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33255991

RESUMO

BACKGROUND: In order to characterize the various subtypes of breast cancer more precisely and improve patients selection for breast conserving therapy (BCT), molecular profiling has gained importance over the past two decades. MicroRNAs, which are small non-coding RNAs, can potentially regulate numerous downstream target molecules and thereby interfere in carcinogenesis and treatment response via multiple pathways. The aim of the current two-phase study was to investigate whether hsa-miR-375-signaling through RASD1 could predict local control (LC) in early breast cancer. RESULTS: The patient and treatment characteristics of 81 individuals were similarly distributed between relapse (n = 27) and control groups (n = 54). In the pilot phase, the primary tumors of 28 patients were analyzed with microarray technology. Of the more than 70,000 genes on the chip, 104 potential hsa-miR-375 target molecules were found to have a lower expression level in relapse patients compared to controls (p-value < 0.2). For RASD1, a hsa-miR-375 binding site was predicted by an in silico search in five mRNA-miRNA databases and mechanistically proven in previous pre-clinical studies. Its expression levels were markedly lower in relapse patients than in controls (p-value of 0.058). In a second phase, this finding could be validated in an independent set of 53 patients using ddPCR. Patients with enhanced levels of hsa-miR-375 compared to RASD1 had a higher probability of local relapse than those with the inverse expression pattern of the two markers (log-rank test, p-value = 0.069). CONCLUSION: This two-phase study demonstrates that hsa-miR-375/RASD1 signaling is able to predict local control in early breast cancer patients, which-to our knowledge-is the first clinical report on a miR combined with one of its downstream target proteins predicting LC in breast cancer.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/genética , Transdução de Sinais/genética , Proteínas ras/genética , Adulto , Idoso , Biologia Computacional/métodos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Redes Reguladoras de Genes/genética , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , RNA Mensageiro/genética
12.
Brain Tumor Pathol ; 37(3): 89-94, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451719

RESUMO

Here, we report on a 28-year old male patient presenting with neck and shoulder pain, dysesthesia of all four limbs and hypesthesia of both hands, without motor deficits. Magnetic resonance imaging showed an intradural, intramedullary mass of the cervical spinal cord of 6.4 cm length and 1.7 cm diameter. The patient underwent surgical resection. Histological and immunohistochemical evaluation showed pleomorphic glial tumor cells, mitoses, calcifications, and atypical ganglioid cells compatible with the morphology of anaplastic ganglioglioma (WHO Grade III). Extensive molecular workup revealed H3F3A K27M, TERT C228T and PDGFRα Y849C mutations indicating poor prognosis. The H3F3A K27M mutation assigned the tumor to the molecular group of diffuse midline glioma (WHO Grade IV). Epigenome-wide methylation profiling confirmed the methylation class of diffuse midline glioma. Thus, this is a very rare case of malignant glioma with H3 K27M genotype phenotypically mimicking anaplastic ganglioglioma. This case emphasizes the importance of comprehensive morphological and molecular workup including methylome profiling for advanced patient care.


Assuntos
Genótipo , Glioma/genética , Glioma/patologia , Histonas/genética , Neoplasias da Medula Espinal/genética , Neoplasias da Medula Espinal/patologia , Adulto , Vértebras Cervicais , Imagem de Difusão por Ressonância Magnética , Ganglioglioma , Glioma/diagnóstico por imagem , Humanos , Masculino , Neoplasias da Medula Espinal/diagnóstico por imagem
13.
Wien Klin Wochenschr ; 129(15-16): 540-544, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28493027

RESUMO

OBJECTIVE: The aim of our investigation was to evaluate the clinicopathological characteristics and mutation patterns in newly diagnosed cases of thyroid cancer in the federal state of Salzburg, Austria, in the year 2013. METHODS: The medical records of all patients newly diagnosed with thyroid cancer in 2013 in the federal state of Salzburg were retrospectively reviewed. The clinicopathological characteristics and mutations of thyroid cancers were analyzed. RESULTS: 63 patients (mean age: 51.0 years, range: 21-81 years; female 75%, male 25%) were identified. 53 patients had papillary (12 follicular variant), 4 patients follicular (1 oxyphilic variant), 3 patients medullary, and 3 patients anaplastic thyroid cancer. T1 tumors were found in 34 patients (pT1a, 20 patients; pT1b, 14 patients), T2 tumors in 10 patients, T3 tumors in 16 patients, and T4 tumors in 3 patients. Lymph node involvement was seen in 15 patients and metastatic disease in 1 patient. Mutations of BRAF (B-type Raf kinase) were detected in 23 and mutation of NRAS (Neuroblastoma RAS Viral Oncogene Homolog) in 2 papillary thyroid cancers. No concomitant mutations of BRAF and NRAS were found. CONCLUSION: Females accounted for 75% of the patients with newly diagnosed thyroid cancer and the incidence peaked at a younger age than in males. Papillary thyroid cancer was the most frequent tumor type, accounting for 84% of the cases. A high frequency of T1 tumors and cancers with no lymph node involvement was found. Males had a higher proportion of large tumors and more aggressive forms of thyroid cancer than females. Mutations (mostly of BRAF) were found in 47% of the cases. Neither mutations of KRAS (Kirsten rat sarcoma viral oncogene homologue) nor concomitant mutations of BRAF and NRAS were found.


Assuntos
Adenocarcinoma Folicular/diagnóstico , Carcinoma Medular/diagnóstico , Câncer Papilífero da Tireoide/diagnóstico , Carcinoma Anaplásico da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Carcinoma Medular/genética , Carcinoma Medular/patologia , Análise Mutacional de DNA , Feminino , GTP Fosfo-Hidrolases/genética , Humanos , Metástase Linfática/genética , Metástase Linfática/patologia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteínas Proto-Oncogênicas B-raf/genética , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/patologia , Carcinoma Anaplásico da Tireoide/genética , Carcinoma Anaplásico da Tireoide/patologia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
14.
Clin Epigenetics ; 8: 28, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26962366

RESUMO

BACKGROUND: A long-term analysis by the Early Breast Cancer Trialist Group (EBCTG) revealed a strong correlation between local control and cancer-specific mortality. MicroRNAs (miRs), short (20-25 nucleotides) non-coding RNAs, have been described as prognosticators and predictors for breast cancer in recent years. The aim of the current study was to identify miRs that can predict local control after breast conserving therapy (BCT) in early stage breast cancer. RESULTS: Clinical data of 46 early stage breast cancer patients with local relapse after BCT were selected from the institutional database. These patients were matched to 101 control patients showing identical clinical features but without local relapse. The study was conducted in two steps. (1) In the pilot study, 32 patients (16 relapses versus 16 controls) were screened for the most de-regulated microRNAs (= candidate microRNAs) in a panel of 1250 miRs by microarray technology. Eight miRs were found to be significantly de-regulated. (2) In the validation study, the candidate microRNAs were analyzed in an independent cohort of 115 patients (30 relapses versus 85 controls) with reverse transcription quantitative polymerase chain reaction (RT-qPCR). From these eight candidates, hsa-miR-375 could be validated. Its median fold change was 2.28 (Mann-Whitney U test, corrected p value = 0.008). In the log-rank analysis, high expression levels of hsa-miR-375 correlated with a significantly higher risk of local relapse (p = 0.003). In a multivariate analysis (forward stepwise regression) including established predictors and prognosticators, hsa-miR-375 was the only variable that was able to distinguish the statistical significance between relapse and control groups (raw p value = 0.000195 HR = 0.76, 95 % CI 0.66-0.88; corrected p value = 0.005). CONCLUSIONS: Hsa-miR-375 predicts local control in patient with early stage breast cancer, especially in estrogen receptor α (ER-α)-positive patients. It can therefore serve as an additional molecular marker for treatment choice independently from known predictors and prognosticators. Validation in larger prospective studies is warranted.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/genética , Adulto , Idoso , Neoplasias da Mama/diagnóstico , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Genes Dev ; 26(15): 1703-13, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22810623

RESUMO

Single-stranded telomeric DNA protrusions are considered to be evolutionarily conserved structural elements essential for chromosome end protection. Their formation at telomeres replicated by the leading strand mechanism is thought to involve poorly understood post-replicative processing of blunt ends. Unexpectedly, we found that angiosperm plants contain blunt-ended and short (1- to 3-nucleotide) G-overhang-containing telomeres that are stably retained in post-mitotic tissues, revealing a novel mechanism of chromosome end protection. The integrity of blunt-ended telomeres depends on the Ku70/80 heterodimer but not on another telomere capping protein, STN1. Curiously, Ku-depleted telomeres are fully functional. They are resected by exonuclease 1, promoting intrachromatid recombination, which may facilitate formation of an alternative capping structure. These data challenge the view that telomeres require ssDNA protrusions for forming a functional capping structure and demonstrate flexibility in solutions to the chromosome end protection problem.


Assuntos
Arabidopsis/metabolismo , Cromossomos de Plantas/metabolismo , Telômero/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , DNA Helicases/metabolismo , DNA de Cadeia Simples/metabolismo , Proteínas de Ligação a DNA/metabolismo , Exodesoxirribonucleases/metabolismo , Recombinação Genética
16.
Mol Cell ; 27(1): 163-9, 2007 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-17612498

RESUMO

Telomeres in mammals and plants are protected by the terminal t loop structure, the formation of which parallels the first steps of intrachromatid homologous recombination (HR). Under some circumstances, cells can also utilize an HR-based mechanism (alternative lengthening of telomeres [ALT]) as a back-up pathway for telomere maintenance. We have found that the Ku70/80 heterodimer, a central nonhomologous end-joining DNA repair factor, inhibits engagement of ALT in Arabidopsis telomerase-negative cells. To further assess HR activities at telomeres, we have developed a sensitive assay for detecting extrachromosomal telomeric circles (t circles) that may arise from t loop resolution and aberrant HR. We show that Ku70/80 specifically inhibits circle formation at telomeres, but not at centromeric and rDNA repeats. Ku inactivation results in increased formation of t circles that represent approximately 4% of total telomeric DNA. However, telomeres in ku mutants are fully functional, indicating that telomerase efficiently heals ongoing terminal deletions arising from excision of the t circles.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , DNA Helicases/metabolismo , DNA Circular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Telômero/metabolismo , Cromossomos de Plantas/genética , Eletroforese em Gel Bidimensional , Mutação/genética
17.
Biochim Biophys Acta ; 1769(5-6): 399-409, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17383025

RESUMO

Telomeres are essential elements of eukaryotic chromosomes that differentiate native chromosome ends from deleterious DNA double-strand breaks (DSBs). This is achieved by assembling chromosome termini in elaborate high-order nucleoprotein structures that in most organisms encompass telomeric DNA, specific telomere-associated proteins as well as general chromatin and DNA repair factors. Although the individual components of telomeric chromatin are evolutionary highly conserved, cross species comparisons have revealed a remarkable flexibility in their utilization at telomeres. This review outlines the strategies used for chromosome end protection and maintenance in mammals, yeast and flies and discusses current progress in deciphering telomere structure in plants.


Assuntos
Plantas/genética , Plantas/metabolismo , Telômero/genética , Telômero/metabolismo , Animais , DNA de Plantas/genética , DNA de Plantas/metabolismo , Drosophila/genética , Drosophila/metabolismo , Modelos Biológicos , Modelos Moleculares , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Telômero/química
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