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1.
Cancer Diagn Progn ; 3(1): 44-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36632583

RESUMO

BACKGROUND/AIM: Lung cancer is one of the most common malignant neoplastic diseases and by far the leading cause of cancer death worldwide. Recently, immune checkpoint inhibitors (ICIs) have received increasing attention for playing a crucial role in non-small cell lung cancer (NSCLC). Biomarkers, such as programmed cell death-ligand 1 (PD-L1) and tumor mutational burden (TMB), seemed to be helpful in selecting patients who are more likely to benefit from ICI treatment: however, their role has not yet been fully clarified. PATIENTS AND METHODS: In this retrospective study, we evaluated the relationship between pre-treatment peripheral blood neutrophil-to-lymphocyte ratio (NLR) and survival in 252 patients suffering from advanced NSCLC who had received pembrolizumab as their first-line immunotherapy. RESULTS: Compared to their NLR low counterparts who had a median overall survival (OS) of 34.8 months, patients with NLRs above 4.8 had a median OS of 7.6 months (HR=3.26, 95%Cl=2.3-4.6, p-value<0.0000001). In multivariate Cox regression analysis, alongside other variables, such as metastatic sites, age, and sex, NLR and PD-L1 predicted progression-free survival and OS; furthermore, a very high NLR - over 10 - seemed to forecast a very dismal prognosis in patients undergoing immunotherapy, with sudden deaths in the days immediately following therapy (median OS=3.8 months). CONCLUSION: NLR acts as a valuable and reliable prognostic factor in non-small cell lung carcinoma patients undergoing first line immunotherapy with pembrolizumab. Additional investigation is necessary to fully elucidate the underlying biological rationale, which can be found in myeloid derived suppressor cells, a heterogeneous population of cells with neutrophil-like immunophenotypic features.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35886338

RESUMO

Kazakhstan is known as a country with a complex radioecological situation resulting from different sources such as a natural radiation background, extensive activities of the industrial system of the former Soviet Union and a well-known testing of nuclear power weapons occurred in the Semipalatinsk Test Site (STS) area. The present study focuses on the assessment of the background of dicentric chromosomes in Kazakhstan's population, which is the starting point in the dose assessment of irradiated people, since the baseline level of spontaneous dicentrics can vary significantly in different populations. In this context, aiming to determine the background frequency of chromosome aberrations in the population of Kazakhstan, considering the heterogeneity of natural radiation background levels of its large territory, a selection of 40 control subjects living in four cities of North, South, West and East Kazakhstan was performed. The cytogenetic study on the selected groups showed fairly low background frequency values of chromosome aberrations (0.84 ± 0.83 per 1000 cells), comparable with other data in the literature on general populations, reporting background frequency values between 0.54 and 2.99 per 1000 cells. The obtained results should be taken into account when constructing the dose-effect calibration curve used in cytogenetic biodosimetry, as a "zero" dose point, which will reduce the uncertainty in quantifying the individual absorbed dose in emergency radiological situations.


Assuntos
Monitoramento Biológico , Guerra Nuclear , Aberrações Cromossômicas , Humanos , Cazaquistão/epidemiologia , U.R.S.S.
3.
J Exp Clin Cancer Res ; 40(1): 281, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488829

RESUMO

BACKGROUND: 223Ra is currently used for treatment of metastatic castration resistant prostate cancer patients (mCRPC) bone metastases with fixed standard activity. Individualized treatments, based on adsorbed dose (AD) in target and non-target tissue, are absolutely needed to optimize efficacy while reducing toxicity of α-emitter targeted therapy. This is a pilot first in human clinical trial aimed to correlate dosimetry, clinical response and biological side effects to personalize 223Ra treatment. METHODS: Out of 20 mCRPC patients who underwent standard 223Ra treatment and dosimetry, in a subset of 5 patients the AD to target and non-target tissues was correlated with clinical effects and radiation-induced chromosome damages. Before each 223Ra administrations, haematological parameters, PSA and ALP values were evaluated. Additional blood samples were obtained baseline (T0), at 7 days (T7), 30 days (T30) and 180 days (T180) to evaluate chromosome damage. After administration WB planar 223Ra images were obtained at 2-4 and 18-24 h. Treatment response and toxicity were monitored with clinical evaluation, bone scan, 18F-choline-PET/CT, PSA value and ALP while haematological parameters were evaluated weekly after 223Ra injection and 2 months after last cycle. RESULTS: 1. a correlation between AD to target and clinical response was evidenced with threshold of 20 Gy as a cut-off to obtain tumor control; 2. the AD to red marrow was lower than 2 Gy in all the patients with no apparently correlation between dosimetry and clinical toxicity. 3. a high dose dependent increase of the number of dicentrics and micronuclei during the course of 223Ra therapy was observed and a linear correlation has been found between blood AD (BAD) and number of dicentrics. CONCLUSIONS: This study provides some interesting preliminary evidence to be further investigated: dosimetry may be useful to identify a more appropriate 223Ra administered activity predicting AD to target tissue; a dose dependent complex chromosome damage occurs during 223Ra administration and this injury is more evident in heavily pre-treated patients; dosimetry could be used for radioprotection purpose. TRIAL REGISTRATION: The pilot study has been approved from the Ethics Committee of Regina Elena National Cancer Institute (N:RS1083/18-2111).


Assuntos
Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Radiometria/métodos , Rádio (Elemento)/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Rádio (Elemento)/farmacologia
4.
Methods Mol Biol ; 2031: 105-119, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31473956

RESUMO

Biological dosimetry is an essential tool for estimating radiation doses received from individuals when the physical dosimetry is not available or inadequate. Early knowledge about the absorbed dose levels in radiation accidents is of paramount importance for selecting the unaffected subjects from those individuals requiring medical evaluation and intervention. A lesson learned from many radiological incidents is the importance to identify the "worried well."Several assays are useful for biological dosimetry approaches, since no one single assay is sufficiently robust for all potential radiation scenarios including early-phase acute exposures, partial-body exposures, and biosampling years after exposure or in case of suspected mixed exposures (radiological and chemicals).The most commonly used biodosimetry methods are based on the evaluation of the radiation-specific dicentric chromosomes (Dic) and micronuclei (MN) in exposed individuals' peripheral blood lymphocytes (PBL).The present chapter does not claim to make an exhaustive and complete picture on the complex world of biodosimetry, to which a large number of specific guidelines for performing laboratory services by the International Organization for Standardization (ISO) are dedicated, but it aims to support the reader in understanding the application of two cytogenetic methods in the individual ionizing radiation dose assessment, suggesting some appropriate scientific sources to consult for each case.


Assuntos
Aberrações Cromossômicas/efeitos da radiação , Linfócitos/efeitos da radiação , Testes para Micronúcleos/métodos , Técnicas de Cultura de Células/métodos , Células Cultivadas , Análise Citogenética/métodos , Humanos , Linfócitos/metabolismo , Radiometria/métodos
5.
Radiat Res ; 189(6): 597-604, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29624483

RESUMO

There is a continued need for further clarification of various aspects of radiation-induced chromosomal aberration, including its correlation with radiation track structure. As part of the EMRP joint research project, Biologically Weighted Quantities in Radiotherapy (BioQuaRT), we performed experimental and theoretical analyses on chromosomal aberrations in Chinese hamster ovary cells (CHO-K1) exposed to α particles with final energies of 5.5 and 17.8 MeV (absorbed doses: ∼2.3 Gy and ∼1.9 Gy, respectively), which were generated by the microbeam at the Physikalisch-Technische Bundesanstalt (PTB) in Braunschweig, Germany. In line with the differences in linear energy transfer (approximately 85 keV/µm for 5.5 MeV and 36 keV/µm for 17.8 MeV α particles), the 5.5 MeV α particles were more effective than the 17.8 MeV α particles, both in terms of the percentage of aberrant cells (57% vs. 33%) and aberration frequency. The yield of total aberrations increased by a factor of ∼2, although the increase in dicentrics plus centric rings was less pronounced than in acentric fragments. The experimental data were compared with Monte Carlo simulations based on the BIophysical ANalysis of Cell death and chromosomal Aberrations model (BIANCA). This comparison allowed interpretation of the results in terms of critical DNA damage [cluster lesions (CLs)]. More specifically, the higher aberration yields observed for the 5.5 MeV α particles were explained by taking into account that, although the nucleus was traversed by fewer particles (nominally, 11 vs. 25), each particle was much more effective (by a factor of ∼3) at inducing CLs. This led to an increased yield of CLs per cell (by a factor of ∼1.4), consistent with the increased yield of total aberrations observed in the experiments.


Assuntos
Partículas alfa/efeitos adversos , Aberrações Cromossômicas/efeitos da radiação , Modelos Biológicos , Animais , Células CHO , Cricetinae , Cricetulus , Humanos
6.
Int J Radiat Biol ; 93(1): 75-80, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27559844

RESUMO

PURPOSE: The RENEB accident exercise was carried out in order to train the RENEB participants in coordinating and managing potentially large data sets that would be generated in case of a major radiological event. MATERIALS AND METHODS: Each participant was offered the possibility to activate the network by sending an alerting email about a simulated radiation emergency. The same participant had to collect, compile and report capacity, triage categorization and exposure scenario results obtained from all other participants. The exercise was performed over 27 weeks and involved the network consisting of 28 institutes: 21 RENEB members, four candidates and three non-RENEB partners. RESULTS: The duration of a single exercise never exceeded 10 days, while the response from the assisting laboratories never came later than within half a day. During each week of the exercise, around 4500 samples were reported by all service laboratories (SL) to be examined and 54 scenarios were coherently estimated by all laboratories (the standard deviation from the mean of all SL answers for a given scenario category and a set of data was not larger than 3 patient codes). CONCLUSIONS: Each participant received training in both the role of a reference laboratory (activating the network) and of a service laboratory (responding to an activation request). The procedures in the case of radiological event were successfully established and tested.


Assuntos
Planejamento em Desastres/organização & administração , Monitoramento de Radiação/métodos , Liberação Nociva de Radioativos , Radiobiologia/educação , Gestão da Segurança/organização & administração , Triagem/organização & administração , Europa (Continente)
7.
Artigo em Inglês | MEDLINE | ID: mdl-27476334

RESUMO

Resveratrol (3,4',5-trihydroxystilbene; RSV) acts on cancer cells in several ways, inducing cell cycle delay and apoptotic death, and enhancing ionizing radiation (IR)-mediated responses. However, fewer studies have examined RSV effects on normal cells. We have treated human lymphocytes in vitro with RSV, either alone or combined with IR, to evaluate its potential use as a radioprotector. We measured the effects of RSV on induction of DNA damage, repair kinetics, and modulation of histone deacetylase activity.


Assuntos
Radiação Ionizante , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/efeitos da radiação , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/efeitos da radiação , Citometria de Fluxo , Humanos , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação , Resveratrol
8.
Cell Mol Neurobiol ; 33(5): 673-80, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23552977

RESUMO

Parkinson's disease (PD) is one of the most common neurodegenerative disorders whose etiology is multifactorial including both hereditary and environmental factors. Currently, pathogenic mutations in at least five genes have been implicated in familial PD generally accounting for less than 10 % of all PD cases in most populations. It has been suggested that polymorphisms in other genes such as those encoding enzymes involved in oxidative metabolism and detoxification could be involved in predisposition to PD since oxidative stress in dopaminergic neurons is thought to be of central importance in the pathogenesis of the disease. The aim of our work was to study the association of genetic polymorphisms in genes involved in oxidative metabolism and detoxification mechanism, namely GSTM1, GSTT1, GSTP1, and those involved in DNA damage repair, OGG1 and XRCC1, in an Italian cohort of sporadic PD patients. We did not detect any association between GSTT1 and GTTM1 null polymorphisms and PD, whereas the 104GSTP1 polymorphism was associated with PD in male patients but not in females. Furthermore, we detected a protective effect of wild type genotype of XRCC1 in women.


Assuntos
Reparo do DNA/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Glutationa Transferase/genética , Doença de Parkinson/epidemiologia , Doença de Parkinson/genética , Polimorfismo Genético , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , DNA Glicosilases/genética , Proteínas de Ligação a DNA/genética , Demografia , Feminino , Frequência do Gene/genética , Glutationa S-Transferase pi/genética , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Doença de Parkinson/enzimologia , Proteína 1 Complementadora Cruzada de Reparo de Raio-X
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