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1.
Crit Rev Oncol Hematol ; 138: 112-119, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31092366

RESUMO

Immune checkpoint inhibitors have changed history and management of different tumor types, including non-small cell lung cancer (NSCLC). Response patterns may be more heterogeneous than those seen with cytotoxic chemotherapy. Besides atypical response patterns, new types of outcome should be taken into account such as pseudo-progression (PP) and hyper-progressive disease (HPD). PP is described as initial tumor increase or appearance of new lesions followed by their shrinkage during immunotherapy treatment while HPD is a rapid and severe pattern of progression with a not yet univocal definition. Physiopathology and underlying mechanism of these phenomena are not completely understood and in absence of reliable clinical and biological markers of response to immunotherapy, radiological evaluation remains a key point in clinicians' decision-making process but further efforts would be useful to identify a unique system of evaluation.In this review we summarize the main radiological criteria available in the evaluation of response to checkpoint inhibitors and we describe peculiar response patterns such PP and HPD with a focus on lung cancer.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Imunoterapia/métodos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Progressão da Doença , Humanos , Resultado do Tratamento
2.
Transl Res ; 202: 99-108, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30080989

RESUMO

Adrenocortical dysplasia (ACD) is a shelterin protein involved in the maintenance of telomere length and in cancer radioresistance. This study investigated the expression profile of ACD in human gliomas and its role in radioresistance of glioma cells. The expression of ACD was analyzed in 62 different grades of glioma tissues and correlated with prognosis. A radioresistant cell line was generated from U87MG cells. For mechanistic studies, ACD was inhibited by small interfering RNA-targeting ACD and the effect on cell radioresistance, telomerase activity, cyclinD1, caspase-3, hTERT, and BIRC1 was evaluated. Clonogenic assay was performed after irradiation, to investigate the effect of ACD silencing on radiation sensitivity. ACD expression appeared strongly upregulated in higher grade gliomas, and its expression was significantly correlated to grading and poor prognosis. In glioma cell lines, ACD expression pattern was similar to those observed in glioma tissues. In irradiated cells, ACD expression was increased in an ionizing radiation dose-dependent manner. A higher expression of ACD was observed in the radioresistant clones than parental cells. Silencing of ACD led to the enhanced radiation sensitivity, decreased telomerase activity and cyclin D1 expression, reduced expression of BIRC1, and finally to the upregulation of caspase-3. This study represents the first report, which demonstrated the expression pattern of ACD in gliomas and its prognostic value. Our results suggested that ACD is involved in glioblastoma radioresistance, likely through the modulation of telomerase activity, proliferation, and apoptosis. ACD might represent a potential molecular biomarker and a novel therapeutic target in glioblastoma.


Assuntos
Neoplasias Encefálicas/metabolismo , Inativação Gênica , Glioblastoma/metabolismo , Tolerância a Radiação , Proteínas de Ligação a Telômeros/metabolismo , Neoplasias Encefálicas/patologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Ciclina D1/metabolismo , Glioblastoma/patologia , Humanos , Gradação de Tumores , Proteína Inibidora de Apoptose Neuronal/metabolismo , Complexo Shelterina , Telomerase/metabolismo
4.
Crit Rev Oncol Hematol ; 123: 149-161, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29482776

RESUMO

In the last few years, the development of targeted therapies for non-small cell lung cancer (NSCLC) expressing oncogenic driver mutations (e.g. EGFR) has changed the clinical management and the survival outcomes of this specific minority of patients. Several phase III trials demonstrated the superiority of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) over chemotherapy in EGFR-mutant NSCLC patients. However, in the vast majority of cases EGFR TKIs lose their clinical activity within 8-12 months. Many genetic aberrations have been described as possible mechanisms of EGFR TKIs acquired resistance and can be clustered in four main sub-groups: 1. Development of secondary EGFR mutations; 2. Activation of parallel signaling pathways; 3. Histological transformation; 4. Activation of downstream signaling pathways. In this review we will describe the molecular alterations underlying each of these EGFR TKIs resistance mechanisms, focusing on the currently available and future therapeutic strategies to overcome these phenomena.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Terapias em Estudo/tendências , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/patologia , Mutação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
5.
Oncotarget ; 8(6): 9144-9154, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-27880720

RESUMO

Reproductive history and exogenous hormonal exposures are acknowledged risk factors for breast cancer in the general population. In women at increased breast cancer risk for genetic predisposition or positive family history, data regarding these risk factors are limited or conflicting, and recommendations for these categories are unclear. We evaluated the characteristics of reproductive life in 2522 women at increased genetic or familial breast cancer risk attending our Family Cancer Center. Breast cancers in BRCA mutation carriers were more likely to be hormone receptor negative, diagnosed at 35 years or before and multiple during the lifetime than tumors in women at increased familial risk, while the distribution of invasive cancers and HER2 positive tumors was similar in the different risk groups. At least one full-term pregnancy (HR 0.27; 95% CI 0.12-0.58; p = 0.001), breastfeeding either less (HR 0.24; 95% CI 0.09-0.66; p = 0.005) or more (HR 0.25; 95% IC 0.08-0.82; p = 0.022) than one year and late age at menopause (HR 0.10; 95% CI 0.01-0.82; p = 0.033) showed to be protective factors in BRCA mutation carriers, while in women at increased familial risk early age at first full-term pregnancy (HR 0.62; 95% IC 0.38-0.99; p = 0.048) and late menarche (HR 0.61; 95% CI 0.42-0.85; p = 0.004) showed to be the main protective factors. Finally, for the entire population, combined hormonal contraceptives demonstrated to do not increase breast cancer risk. The results of our study suggest that women at high familial risk and mutation carries develop tumors with different clinical-pathological characteristics and, consequently, are influenced by different protective and risk factors.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Fertilidade , Mutação , Saúde Reprodutiva , Adulto , Idoso , Aleitamento Materno , Neoplasias da Mama/terapia , Distribuição de Qui-Quadrado , Anticoncepcionais Orais Sequenciais/efeitos adversos , Feminino , Predisposição Genética para Doença , Hereditariedade , Humanos , Itália , Menarca , Menopausa , Pessoa de Meia-Idade , Paridade , Linhagem , Fenótipo , Gravidez , Modelos de Riscos Proporcionais , Fatores de Risco , Fatores de Tempo
6.
Oncol Lett ; 12(4): 2992-2998, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27698888

RESUMO

Sirtuins are a family of 7 histone deacetylases largely involved in the regulation of cell proliferation, survival and death. The role of sirtuins in tumorigenesis and cancer progression has been previously studied in certain cancer types. Few studies have investigated sirtuin expression in gliomas, with controversial results. The aim of the present study was to investigate the expression of sirtuin-1 (Sirt-1) in diffuse astrocytoma [low grade astrocytoma (LGA)], anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM) and in primary glioma cell lines: PLGAC (primary LGA cells); PAAC (primary AA cells); and PGBMC (primary GBM cells). Tumor samples were obtained from patients who underwent craniotomy for microsurgical tumor resection at the Neurosurgery Unit of the University of Messina between 2011 and 2014. Sirt-1 expression was qualitatively analyzed in 30 human glial tumor samples and 5 non-neoplastic brain tissue (NBT) specimens using immunohistochemistry and western blotting techniques. Sirt-1 expression was quantitatively analyzed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). In addition, Sirt-1 expression in primary cell lines was investigated by immunoblotting and RT-qPCR. Sirt-1 expression was downregulated in gliomas compared to NBTs. Sirt-1 levels also varied among different tumor grades, with more evident downregulation in high-grade (P<0.001) than low-grade tumors (P<0.01). These data were confirmed in cell lines, with the exception of upregulation of protein level in the highest malignancy grade cell lines. The present results suggest a role for miRNA-34a, miRNA-132 and miRNA-217 in the epigenetic control of Sirt-1 during gliomagenesis and progression, and demonstrate the different implications of Sirt-1 in human tissues and cell lines. Furthermore, the present results reveal that Sirt-1 may be an intrinsic regulator of tumor progression and the regulation of Sirt-1 involves complex molecular pathways. However, the biological functions of Sirt-1 in gliomagenesis require additional investigation.

7.
Cancer Genomics Proteomics ; 13(5): 369-79, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27566655

RESUMO

Meningiomas are one of the most common tumors affecting the central nervous system, exhibiting a great heterogeneity in grading, treatment and molecular background. This article provides an overview of the current literature regarding the molecular aspect of meningiomas. Analysis of potential biomarkers in serum, cerebrospinal fluid (CSF) and pathological tissues was reported. Applying bioinformatic methods and matching the common proteic profile, arising from different biological samples, we highlighted the role of nine proteins, particularly related to tumorigenesis and grading of meningiomas: serpin peptidase inhibitor alpha 1, ceruloplasmin, hemopexin, albumin, C3, apolipoprotein, haptoglobin, amyloid-P-component serum and alpha-1-beta-glycoprotein. These proteins and their associated pathways, including complement and coagulation cascades, plasma lipoprotein particle remodeling and lipid metabolism could be considered possible diagnostic, prognostic biomarkers, and eventually therapeutic targets. Further investigations are needed to better characterize the role of these proteins and pathways in meningiomas. The role of new therapeutic strategies are also discussed.


Assuntos
Meningioma/metabolismo , Proteoma , Proteômica , Biomarcadores , Biologia Computacional/métodos , Ontologia Genética , Humanos , Meningioma/genética , Mapeamento de Interação de Proteínas , Mapas de Interação de Proteínas , Proteômica/métodos , Transdução de Sinais
8.
Tumour Biol ; 37(10): 14035-14048, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27495233

RESUMO

The role of microRNAs (miRNAs) in glioma biology is increasingly recognized. To investigate the regulatory mechanisms governing the malignant signature of gliomas with different grades of malignancy, we analyzed miRNA expression profiles in human grade I-IV tumor samples and primary glioma cell cultures. Multiplex real-time PCR was used to profile miRNA expression in a set of World Health Organization (WHO) grade I (pilocytic astrocytoma), II (diffuse fibrillary astrocytoma), and IV (glioblastoma multiforme) astrocytic tumors and primary glioma cell cultures. Primary glioma cell cultures were used to evaluate the effect of transfection of specific miRNAs and miRNA inhibitors. miRNA microarray showed that a set of miRNAs was consistently upregulated in all glioma samples. miR-363 was upregulated in all tumor specimens and cell lines, and its expression correlated with tumor grading. The transfection of glioma cells with the specific inhibitor of miR-363 increased the expression level of tumor suppressor growth-associated protein 43 (GAP-43). Transfection of miR-363 induced cell survival, while inhibition of miR-363 significantly reduced glioma cell viability. Furthermore, miRNA-363 inhibition induced the downregulation of AKT, cyclin-D1, matrix metalloproteinase (MMP)-2, MMP-9, and Bcl-2 and upregulation of caspase 3. Together, these data suggest that the upregulation of miR-363 may play a role in malignant glioma signature.


Assuntos
Apoptose , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Glioma/patologia , MicroRNAs/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Seguimentos , Proteína GAP-43/genética , Proteína GAP-43/metabolismo , Glioma/genética , Glioma/metabolismo , Glioma/cirurgia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Células Tumorais Cultivadas , Proteínas rap1 de Ligação ao GTP/genética , Proteínas rap1 de Ligação ao GTP/metabolismo
9.
Biomed Res Int ; 2015: 341723, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075229

RESUMO

More than one-fifth of ovarian tumors have hereditary susceptibility and, in about 65-85% of these cases, the genetic abnormality is a germline mutation in BRCA genes. Nevertheless, several other suppressor genes and oncogenes have been associated with hereditary ovarian cancers, including the mismatch repair (MMR) genes in Lynch syndrome, the tumor suppressor gene, TP53, in the Li-Fraumeni syndrome, and several other genes involved in the double-strand breaks repair system, such as CHEK2, RAD51, BRIP1, and PALB2. The study of genetic discriminators and deregulated pathways involved in hereditary ovarian syndromes is relevant for the future development of molecular diagnostic strategies and targeted therapeutic approaches. The recent development and implementation of next-generation sequencing technologies have provided the opportunity to simultaneously analyze multiple cancer susceptibility genes, reduce the delay and costs, and optimize the molecular diagnosis of hereditary tumors. Particularly, the identification of mutations in ovarian cancer susceptibility genes in healthy women may result in a more personalized cancer risk management with tailored clinical and radiological surveillance, chemopreventive approaches, and/or prophylactic surgeries. On the other hand, for ovarian cancer patients, the identification of mutations may provide potential targets for biologic agents and guide treatment decision-making.


Assuntos
Proteína BRCA1 , Proteína BRCA2 , Reparo de Erro de Pareamento de DNA , Predisposição Genética para Doença , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/metabolismo , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Neoplasias Colorretais Hereditárias sem Polipose/terapia , Feminino , Humanos , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/metabolismo , Síndrome de Li-Fraumeni/patologia , Síndrome de Li-Fraumeni/terapia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia
10.
Springerplus ; 4: 37, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25674497

RESUMO

Single fraction radiosurgery is conventionally precluded for lesions lying <2-3 mm of the anterior visual pathway because of the radiosensitivity of the optic nerve. We analyzed a series of 64 patients with "perioptic" meningiomas treated by CyberKnife multisession radiosurgery and hypofractionated stereotactic radiotherapy (hSRT). Between July 2007-May 2010, patients were treated using conventional multisession Cyberknife schemes (2-5 fractions) and results were retrospectively analyzed. A radiobiological model was then developed to estimate the best tumor control probability (TCP)/ normal tissue complication probability (NTCP) for these lesions. Resulting dose/fraction schemes were applied to patients treated between May 2010 and July 2014. Data were prospectively collected Twenty-five patients were included in the retrospective part of the study. Median tumor volume was 4.95 cc; median dose was 23.0 Gy and median number of fraction was 5 (range 2-5). No patient had visual deterioration at mean follow-up of 60 ± 12 months. Tumor control was achieved in all cases. Thirty-nine patients were treated according the radiobiology model and results prospectively analyzed. Median tumor volume was 7.5 cc, median dose 25.0 Gy and mean number of fraction 5 (range 3-15). No patient had visual deterioration or tumor progression at mean follow-up of 17 ± 10 months. Conventional multisession CyberKnife treatments (2-5 fractions) provided satisfactory results. Nonetheless, our estimation of TCP suggests the use of higher doses to grant long-term disease control. To achieve higher equivalent doses without significantly increasing the NTCP, we suggest the use of a greater number of fractions, moving to hSRT, in tumors in which the encasement of optic nerves is presumed.

11.
Stroke ; 45(10): 2959-66, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25184356

RESUMO

BACKGROUND AND PURPOSE: Cerebral autosomal-dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), a rare autosomal dominant disorder caused by NOTCH3 mutations, is characterized by vascular smooth muscle and endothelial cells abnormalities, altered vasoreactivity, and recurrent lacunar infarcts. Vasomotor function may represent a key factor for disease progression. Tetrahydrobiopterin, essential cofactor for nitric oxide synthesis in endothelial cells, ameliorates endothelial function. We assessed whether supplementation with sapropterin, a synthetic tetrahydrobiopterin analog, improves endothelium-dependent vasodilation in CADASIL patients. METHODS: In a 24-month, multicenter randomized, double-blind, placebo-controlled trial, CADASIL patients aged 30 to 65 years were randomly assigned to receive placebo or sapropterin 200 to 400 mg BID. The primary end point was change in the reactive hyperemia index by peripheral arterial tonometry at 24 months. We also assessed the safety and tolerability of sapropterin. Analysis was done by intention-to-treat. RESULTS: The intention-to-treat population included 61 patients. We found no significant difference between sapropterin (n=32) and placebo (n=29) in the primary end point (mean difference in reactive hyperemia index by peripheral arterial tonometry changes 0.19 [95% confidence interval, -0.18, 0.56]). Reactive hyperemia index by peripheral arterial tonometry increased after 24 months in 37% of patients on sapropterin and in 28% on placebo; however, after adjustment for age, sex, and clinical characteristics, improvement was not associated with treatment arm. The proportion of patients with adverse events was similar on sapropterin and on placebo (50% versus 48.3%); serious adverse events occurred in 6.3% versus 13.8%, respectively. CONCLUSIONS: Sapropterin was safe and well-tolerated at the average dose of 5 mg/kg/day, but did not affect endothelium-dependent vasodilation in CADASIL patients. CLINICAL TRIAL REGISTRATION URL: https://www.clinicaltrialsregister.eu. Unique identifier: 2007-004370-55.


Assuntos
Biopterinas/análogos & derivados , CADASIL/tratamento farmacológico , Endotélio Vascular/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Adulto , Idoso , Biopterinas/farmacologia , Método Duplo-Cego , Feminino , Humanos , Hiperemia/tratamento farmacológico , Masculino , Pessoa de Meia-Idade
12.
J Neurol ; 260(12): 3134-43, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24122064

RESUMO

The role of the cerebellum in cognition, both in healthy subjects and in patients with cerebellar diseases, is debated. Neuropsychological studies in spinocerebellar ataxia type 1 (SCA1) and type 2 (SCA2) demonstrated impairments in executive functions, verbal memory, and visuospatial performances, but prospective evaluations are not available. Our aims were to assess progression of cognitive and psychiatric functions in patients with SCA1 and SCA2 in a longitudinal study. We evaluated at baseline 20 patients with SCA1, 22 patients with SCA2 and 17 matched controls. Two subgroups of patients (9 SCA1, 11 SCA2) were re-evaluated after 2 years. We tested cognitive functions (Mini Mental State Examination, digit span, Corsi span, verbal memory, attentional matrices, modified Wisconsin Card Sorting Test, Raven Progressive Matrices, Benton test, phonemic and semantic fluency), psychiatric status (Scales for Assessment of Negative and Positive Symptoms, Hamilton Depression and Anxiety Scales), neurological conditions (Scale for Assessment and Rating of Ataxia), and functional abilities (Unified Huntington Disease Rating Scale­part IV). At baseline, SCA1 and SCA2 patients had significant deficits compared to controls, mainly in executive functions (phonemic and semantic fluencies, attentional matrices); SCA2 showed further impairment in visuospatial and visuoperceptive tests (Raven matrices, Benton test, Corsi span). Both SCA groups had higher depression and negative symptoms, particularly apathy, compared to controls. After 2 years, motor and functional disability worsened, while only attentive performances deteriorated in SCA2. This longitudinal study showed dissociation in progression of motor disability and cognitive impairment, suggesting that in SCA1 and SCA2 motor and cognitive functions might be involved with different progression rates.


Assuntos
Transtornos Cognitivos/psicologia , Ataxias Espinocerebelares/psicologia , Transtornos Cognitivos/etiologia , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos
13.
PLoS One ; 8(6): e67077, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23799141

RESUMO

The altered aggregation of proteins in non-native conformation is associated with endoplasmic reticulum derangements, mitochondrial dysfunction and excessive production of reactive oxygen species. Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare hereditary systemic vasculopathy, caused by NOTCH3 mutations within the receptor extracellular domain, that lead to abnormal accumulation of the mutated protein in the vascular wall. NOTCH3 misfolding could cause free radicals increase also in CADASIL. Aim of the study was to verify whether CADASIL patients have increased oxidative stress compared to unrelated healthy controls. We enrolled 15 CADASIL patients and 16 gender- and age-matched healthy controls with comparable cardiovascular risk factor. Blood and plasma reduced and total aminothiols (homocysteine, cysteine, glutathione, cysteinylglycine) were measured by HPLC and plasma 3-nitrotyrosine by ELISA. Only plasma reduced cysteine (Pr-Cys) and blood reduced glutathione (Br-GSH) concentrations differed between groups: in CADASIL patients Br-GSH levels were higher (p = 0.019) and Pr-Cys lower (p = 0.010) than in controls. No correlation was found between Br-GSH and Pr-Cys either in CADASIL patients (rho 0.25, P = 0.36) or in controls (rho -0.15, P = 0.44). Conversely, 3-nitrotyrosine values were similar in CADASIL and healthy subjects (p = 0.82). The high levels of antioxidant molecules and low levels of oxidant mediators found in our CADASIL population might either be expression of an effective protective action against free radical formation at an early stage of clinical symptoms or they could suggest that oxidative stress is not directly involved in the pathogenesis of CADASIL.


Assuntos
CADASIL/sangue , Estresse Oxidativo , Adulto , Antioxidantes/metabolismo , Estudos de Casos e Controles , Cisteína/sangue , Dipeptídeos/sangue , Feminino , Glutationa/sangue , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Oxidantes/sangue , Oxirredução , Tirosina/análogos & derivados , Tirosina/sangue
14.
PLoS One ; 8(5): e64296, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23691191

RESUMO

BACKGROUND: Telomeres alteration during carcinogenesis and tumor progression has been described in several cancer types. Telomeres length is stabilized by telomerase (h-TERT) and controlled by several proteins that protect telomere integrity, such as the Telomere Repeat-binding Factor (TRF) 1 and 2 and the tankyrase-poli-ADP-ribose polymerase (TANKs-PARP) complex. OBJECTIVE: To investigate telomere dysfunction in astroglial brain tumors we analyzed telomeres length, telomerase activity and the expression of a panel of genes controlling the length and structure of telomeres in tissue samples obtained in vivo from astroglial brain tumors with different grade of malignancy. MATERIALS AND METHODS: Eight Low Grade Astrocytomas (LGA), 11 Anaplastic Astrocytomas (AA) and 11 Glioblastoma Multiforme (GBM) samples were analyzed. Three samples of normal brain tissue (NBT) were used as controls. Telomeres length was assessed through Southern Blotting. Telomerase activity was evaluated by a telomere repeat amplification protocol (TRAP) assay. The expression levels of TRF1, TRF2, h-TERT and TANKs-PARP complex were determined through Immunoblotting and RT-PCR. RESULTS: LGA were featured by an up-regulation of TRF1 and 2 and by shorter telomeres. Conversely, AA and GBM were featured by a down-regulation of TRF1 and 2 and an up-regulation of both telomerase and TANKs-PARP complex. CONCLUSIONS: In human astroglial brain tumours, up-regulation of TRF1 and TRF2 occurs in the early stages of carcinogenesis determining telomeres shortening and genomic instability. In a later stage, up-regulation of PARP-TANKs and telomerase activation may occur together with an ADP-ribosylation of TRF1, causing a reduced ability to bind telomeric DNA, telomeres elongation and tumor malignant progression.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Glioblastoma/genética , Telômero/genética , Adulto , Idoso , Astrocitoma/enzimologia , Astrocitoma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/patologia , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Glioblastoma/enzimologia , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Poli(ADP-Ribose) Polimerases/genética , Tanquirases/genética , Telomerase/genética , Proteína 1 de Ligação a Repetições Teloméricas/genética , Proteína 2 de Ligação a Repetições Teloméricas/genética
16.
Acta Neurochir (Wien) ; 154(2): 203-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21984132

RESUMO

BACKGROUND: Stereotactic radiosurgery (SRS) can be a useful adjunct to the treatment of recurrent glioblastoma multiforme (GBM). Its combination with chemotherapy is attractive for the possible radiosensitization effect and cytotoxicity on tumor cells in distant areas. The aim of this study was to evaluate the efficacy and toxicity of CyberKnife SRS alone and combined with a "dose-dense" administration of temozolomide (TMZ) for recurrent GBM. METHODS: Between July 2007 and July 2010, 23 patients underwent CyberKnife SRS. In 12 patients irradiation was combined with TMZ at 75 mg/m(2)/day for 21 days every 28 days. The median prescription dose in this group was 20 Gy (mean 20.7 ± 4 Gy) with a median number of fractions of 2. The median dose for the 11 patients who underwent SRS alone was 20 Gy (mean 19.9 ± 4.4 Gy; p = NS). RESULTS: The median survival was 12 months for patients who underwent SRS/TMZ and 7 months for those who received SRS alone (p < 0.01). The 6-month progression-free survival (PFS) of the SRS/TMZ group was 66.7% vs. 18% for those who underwent SRS alone (p = 0.03). The median time to progression (TTP) was 7 months for patients who underwent SRS/TMZ and 4 months for those who underwent SRS alone (p = 0.01). Corticosteroid dependency was developed by most patients; radionecrosis was evident in one patient (4.3%) receiving TMZ. Grade 3 hematological toxicity was recorded in >40% of patients receiving chemotherapy. CONCLUSIONS: The results suggest that Cyberknife re-treatments are relatively safe using selected dose/fraction schemes. The combination with TMZ improved patients' outcomes with OS and 6-month PFS that favorably compares with alternative treatments, but the incidence of major adverse effects was >40%. Further studies are warranted.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Glioblastoma/cirurgia , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/cirurgia , Antineoplásicos Alquilantes/uso terapêutico , Astenia/induzido quimicamente , Neoplasias Encefálicas/mortalidade , Dacarbazina/efeitos adversos , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Feminino , Glioblastoma/mortalidade , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Radiocirurgia , Reoperação , Taxa de Sobrevida , Temozolomida , Vômito/induzido quimicamente
17.
J Neurol Neurosurg Psychiatry ; 83(3): 268-74, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22072702

RESUMO

BACKGROUND AND PURPOSE: CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is a rare genetic disease caused by NOTCH3 gene mutations. A dysfunction in vasoreactivity has been proposed as an early event in the pathogenesis of the disease. The aim of this study was to verify whether endothelium dependent and/or independent function is altered in CADASIL patients with respect to controls. METHODS: Vasoreactivity was studied by a non-invasive pletismographic method in 49 mildly disabled CADASIL patients (30-65 years, 58% male, Rankin scale ≤2) and 25 controls. Endothelium dependent vasodilatation was assessed by reactive hyperaemia (flow mediated dilation-peripheral arterial tone (FMD-PAT)) and endothelium independent vasoreactivity by glyceryl trinitrate (GTN) administration (GTN-PAT). RESULTS: Patients and controls showed comparable age, gender and cardiovascular risk factor distribution. GTN-PAT values were significantly lower in CADASIL patients (1.54 (1.01 to 2.25)) than in controls (1.89 (1.61 to 2.59); p=0.041). FMD-PAT scores did not differ between patients and controls (1.88 (1.57 to 2.43) vs 2.08 (1.81 to 2.58); p=0.126) but 17 CADASIL patients (35%) had FMD-PAT scores below the fifth percentile of controls. FMD-PAT and GTN-PAT values correlated both in controls (ρ=0.648, p<0.001) and CADASIL patients (ρ=0.563, p<0.001). By multivariable logistic regression for clinical and laboratory variables, only GTN-PAT (OR 0.39, 95% CI 0.15 to 0.97; p=0.044) was independently associated with FMD-PAT below the fifth percentile in CADASIL patients. CONCLUSIONS: The impaired vasoreactivity observed in CADASIL patients highlights the fact that both endothelial and smooth muscle functional alterations may already be present in mildly disabled subjects. The improvement in vascular function could be a new target for pharmacological trials in CADASIL patients.


Assuntos
CADASIL/fisiopatologia , Músculo Liso Vascular/fisiopatologia , Adulto , Vasos Sanguíneos/fisiopatologia , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Manometria , Pessoa de Meia-Idade , Neuroimagem , Pletismografia
18.
Leuk Lymphoma ; 52(9): 1689-96, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21663500

RESUMO

We conducted a population-based study to assess how positron emission tomography (PET) is currently used in patients with Hodgkin lymphoma (HL). Four cancer registries from northern Italy were used to identify patients with HL diagnosed from 2006 to 2008. Computed tomography (CT) and PET scans were collected before treatment start (B), at the end (F), and during treatment (I). One hundred and thirty-six patients were identified as the study population. B-PET, I-PET, and F-PET were performed in 82%, 65%, and 85% of patients, respectively. Overall, I-PET was coded as positive in 16% of cases. F-PET was positive in 13% of cases. The I-PET result was a prognostic factor for failure-free survival (FFS) (hazard ratio [HR] 5.33); the F-PET result was the only prognostic factor for overall survival (OS) (HR 14.2). This population-based study confirms the prognostic role of I-PET for FFS also in daily practice; the results of F-PET can be used to predict OS.


Assuntos
Fluordesoxiglucose F18 , Doença de Hodgkin/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adolescente , Adulto , Idoso , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Doença de Hodgkin/terapia , Humanos , Itália , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento , Adulto Jovem
19.
Cancers (Basel) ; 2(2): 693-712, 2010 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-24281089

RESUMO

Gliomas are the most common primary brain tumors of the central nervous system. Despite relevant progress in conventional treatments, the prognosis of such tumors remains almost invariably dismal. The genesis of gliomas is a complex, multistep process that includes cellular neoplastic transformation, resistance to apoptosis, loss of control of the cell cycle, angiogenesis, and the acquisition of invasive properties. Among a number of different biomolecular events, the existence of molecular connections between inflammation and oxidative stress pathways and the development of this cancer has been demonstrated. In particular, the tumor microenvironment, which is largely orchestrated by inflammatory molecules, is an indispensable participant in the neoplastic process, promoting proliferation, survival and migration of such tumors. Proinflammatory cytokines, such as tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma, as well as chemokines and prostaglandins, are synthesized by resident brain cells and lymphocytes invading the affected brain tissue. Key mediators of cancer progression include nuclear factor-kappaB, reactive oxygen and nitrogen species, and specific microRNAs. The collective activity of these mediators is largely responsible for a pro-tumorigenic response through changes in cell proliferation, cell death, cellular senescence, DNA mutation rates, DNA methylation and angiogenesis. We provide a general overview of the connection between specific inflammation and oxidative stress pathway molecules and gliomas. The elucidation of specific effects and interactions of these factors may provide the opportunity for the identification of new target molecules leading to improved diagnosis and treatment.

20.
J Neurol ; 256(11): 1926-8, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19644730

RESUMO

We report a rare association of spinocerebellar ataxia and motor neuron disease (MND) in a woman with genetically confirmed SCA2 who subsequently developed a rapidly progressive and fatal form of MND. Considering the rarity of these two neurological conditions, it is interesting to note that the concomitant occurrence of SCA mutations and MND have been previously observed in three cases: in one patient affected by SCA6 and two other cases with SCA2.


Assuntos
Doença dos Neurônios Motores/complicações , Ataxias Espinocerebelares/complicações , Idoso , Feminino , Humanos
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