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1.
Cancer Cell Int ; 24(1): 56, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317193

RESUMO

BACKGROUND: About 30% of Prostate cancer (PCa) patients progress to metastatic PCa that remains largely incurable. This evidence underlines the need for the development of innovative therapies. In this direction, the potential research focus might be on long non-coding RNAs (lncRNAs) like H19, which serve critical biological functions and show significant dysregulation in cancer. Previously, we showed a transcriptional down-regulation of H19 under combined pro-tumoral estrogen and hypoxia treatment in PCa cells that, in turn, induced both E-cadherin and ß4 integrin expression. H19, indeed, acts as transcriptional repressor of cell adhesion molecules affecting the PCa metastatic properties. Here, we investigated the role of H19/cell adhesion molecules circuitry on in vivo PCa experimental tumor growth and metastatic dissemination models. METHODS: H19 was silenced in luciferase-positive PC-3 and 22Rv1 cells and in vitro effect was evaluated by gene expression, proliferation and invasion assays before and after treatment with the histone lysine demethylase inhibitor, GSK-J4. In vivo tumor growth and metastasis dissemination, in the presence or absence of GSK-J4, were analyzed in two models of human tumor in immunodeficient mice by in vivo bioluminescent imaging and immunohistochemistry (IHC) on explanted tissues. Organotypic Slice Cultures (OSCs) from fresh PCa-explant were used as ex vivo model to test GSK-J4 effects. RESULTS: H19 silencing in both PC-3 and 22Rv1 cells increased: i) E-cadherin and ß4 integrin expression as well as proliferation and invasion, ii) in vivo tumor growth, and iii) metastasis formation at bone, lung, and liver. Of note, treatment with GSK-J4 reduced lesions. In parallel, GSK-J4 efficiently induced cell death in PCa-derived OSCs. CONCLUSIONS: Our findings underscore the potential of the H19/cell adhesion molecules circuitry as a targeted approach in PCa treatment. Modulating this interaction has proven effective in inhibiting tumor growth and metastasis, presenting a logical foundation for targeted therapy.

2.
Eur Stroke J ; 8(2): 501-507, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37231696

RESUMO

INTRODUCTION: Marfan syndrome (MFS) is the most common inherited connective tissue disorder and its association with intracranial aneurysms (ICAs) has been debated for more than two decades. Here, we report the prevalence of ICAs at screening neuroimaging in a population of genetically confirmed MFS patients and present the results of a meta-analysis including our cohort of patients and those of previous studies. PATIENTS AND METHODS: We enrolled 100 consecutive MFS patients, who underwent screening with brain magnetic resonance angiography at our tertiary center between August 2018 and May 2022. We did a PubMed and Web of Science search to retrieve all studies on the prevalence of ICAs in patients with MFS published before November, 2022. RESULTS: Of the 100 patients included in this study (94% Caucasians, 40% females, mean age 38.6 ± 14.6 years), three had an ICA. We pooled the current study with five previously published studies, including a total of 465 patients, 43 of which harbored at least one unruptured ICA, leading to an overall ICA prevalence of 8.9% (95% CI 5.8%-13.3%). DISCUSSION AND CONCLUSION: In our cohort of genetically confirmed MFS patients, the prevalence of ICAs was 3%, which is substantially lower compared to previous studies based on neuroimaging. The high frequency of ICA found in previous studies could be explained by selection bias and lack of genetic testing, which may have led to the inclusion of patients with different connective tissue disorders. Further studies, including several centers and a large number of patients with genetically confirmed MFS, are needed to confirm our results.


Assuntos
Doenças do Tecido Conjuntivo , Aneurisma Intracraniano , Síndrome de Marfan , Feminino , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Masculino , Síndrome de Marfan/epidemiologia , Estudos Transversais , Aneurisma Intracraniano/diagnóstico por imagem , Prevalência , Doenças do Tecido Conjuntivo/complicações
3.
Autophagy ; 19(7): 2078-2093, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36704963

RESUMO

Macroautophagy/autophagy has been shown to exert a dual role in cancer i.e., promoting cell survival or cell death depending on the cellular context and the cancer stage. Therefore, development of potent autophagy modulators, with a clear mechanistic understanding of their target action, has paramount importance in both mechanistic and clinical studies. In the process of exploring the mechanism of action of a previously identified cytotoxic small molecule (SM15) designed to target microtubules and the interaction domain of microtubules and the kinetochore component NDC80/HEC1, we discovered that the molecule acts as a potent autophagy inhibitor. By using several biochemical and cell biology assays we demonstrated that SM15 blocks basal autophagic flux by inhibiting the fusion of correctly formed autophagosomes with lysosomes. SM15-induced autophagic flux blockage promoted apoptosis-mediated cell death associated with ROS production. Interestingly, autophagic flux blockage, apoptosis induction and ROS production were rescued by genetic or pharmacological inhibition of OGT (O-linked N-acetylglucosamine (GlcNAc) transferase) or by expressing an O-GlcNAcylation-defective mutant of the SNARE fusion complex component SNAP29, pointing to SNAP29 as the molecular target of SM15 in autophagy. Accordingly, SM15 was found to enhance SNAP29 O-GlcNAcylation and, thereby, inhibit the formation of the SNARE fusion complex. In conclusion, these findings identify a new pathway in autophagy connecting O-GlcNAcylated SNAP29 to autophagic flux blockage and autophagosome accumulation, that, in turn, drives ROS production and apoptotic cell death. Consequently, modulation of SNAP29 activity may represent a new opportunity for therapeutic intervention in cancer and other autophagy-associated diseases.


Assuntos
Autofagossomos , Autofagia , Autofagossomos/metabolismo , Autofagia/fisiologia , Macroautofagia , Espécies Reativas de Oxigênio/metabolismo , Lisossomos/metabolismo , Proteínas SNARE/metabolismo , Apoptose
4.
Cancers (Basel) ; 14(12)2022 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-35740569

RESUMO

BACKGROUND: Choline kinase alpha (CHKA), an essential gene in phospholipid metabolism, is among the modulated MALAT1-targeted transcripts in advanced and metastatic prostate cancer (PCa). METHODS: We analyzed CHKA mRNA by qPCR upon MALAT1 targeting in PCa cells, which is characterized by high dose-responsiveness to the androgen receptor (AR) and its variants. Metabolome analysis of MALAT1-depleted cells was performed by quantitative High-resolution 1 H-Nuclear Magnetic Resonance (NMR) spectroscopy. In addition, CHKA genomic regions were evaluated by chromatin immunoprecipitation (ChIP) in order to assess MALAT1-dependent histone-tail modifications and AR recruitment. RESULTS: In MALAT1-depleted cells, the decrease of CHKA gene expression was associated with reduced total choline-containing metabolites compared to controls, particularly phosphocholine (PCho). Upon MALAT1 targeting a significant increase in repressive histone modifications was observed at the CHKA intron-2, encompassing relevant AR binding sites. Combining of MALAT1 targeting with androgen treatment prevented MALAT1-dependent CHKA silencing in androgen-responsive (LNCaP) cells, while it did not in hormone-refractory cells (22RV1 cells). Moreover, AR nuclear translocation and its activation were detected by confocal microscopy analysis and ChIP upon MALAT1 targeting or androgen treatment. CONCLUSIONS: These findings support the role of MALAT1 as a CHKA activator through putative association with the liganded or unliganded AR, unveiling its targeting as a therapeutic option from a metabolic rewiring perspective.

5.
Radiol Med ; 127(4): 414-425, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35226245

RESUMO

PURPOSE: To assess utility of computed tomography perfusion (CTP) protocols for selection of patients with acute ischemic stroke (AIS) for reperfusive treatments and compare the diagnostic accuracy (ACC) in predicting follow-up infarction, using time-to-maximum (Tmax) maps. METHODS: We retrospectively reviewed consecutive AIS patients evaluated for reperfusive treatments at comprehensive stroke center, employing a multimodal computed tomography. To assess prognostic accuracy of CTP summary maps in predicting final infarct area (FIA) in AIS patients, we assumed the best correlation between non-viable tissue (NVT) and FIA in early and fully recanalized patients and/or in patients with favorable clinical response (FCR). On the other hand, the tissue at risk (TAR) should better correlate with FIA in untreated patients and in treatment failure. RESULTS: We enrolled 158 patients, for which CTP maps with Tmax thresholds of 9.5 s and 16 s, presented sensitivity of 82.5%, specificity of 74.6%, and ACC of 75.9%. In patients selected for perfusion deficit in anterior circulation territory, CTP-Tmax > 16 s has proven relatively reliable to identify NVT in FCR patients, with a tendency to overestimate NVT. Similarly, CTP-Tmax > 9.5 s was reliable for TAR, but it was overestimated comparing to FIA, in patients with unfavorable outcomes. CONCLUSIONS: In our experience, Tmax thresholds have proven sufficiently reliable to identify global hypoperfusion, with tendency to overestimate both NVT and TAR, not yielding satisfactory differentiation between true penumbra and benign oligoemia. In particular, the overestimation of NVT could have serious consequences in not selecting potential candidates for a reperfusion treatment.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Circulação Cerebrovascular/fisiologia , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/terapia , Perfusão , Estudos Retrospectivos , Acidente Vascular Cerebral/diagnóstico por imagem
6.
Neuroradiol J ; 33(5): 416-423, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32539656

RESUMO

We present the neuroimaging findings of three cases of non-ketotic hyperglycaemia (NKH) associated with focal seizures and a review of the previous cases and series reported in literature. NKH is a cause of seizures in both long-standing and newly diagnosed diabetic patients. They are usually focal motor seizures, rarely with a secondary generalisation. This condition does not fully respond to anticonvulsant therapy if glycaemic levels are not normalised. Of interest, magnetic resonance imaging (MRI) of NKH could be different from those observed during other kinds of seizures. Indeed, seizure-related MRI abnormalities mainly involve the cortical grey matter, while NKH-related seizures usually appear as reversible subcortical T2/fluid attenuation inversion recovery (FLAIR) hypointensity. This latter abnormality shows a good spatial correlation with the area of the ictal focus on electroencephalogram and could be associated with other more common post-ictal MRI changes (cortical grey matter T2/FLAIR hyperintensity, cortical or leptomeningeal enhancement). Although these abnormalities tend to be transient, a focal volume loss or gliosis can result on follow-up imaging. Our cases confirm T2/FLAIR subcortical hypointensity as a main neuroradiological hallmark of NKH-induced seizures.


Assuntos
Hiperglicemia/complicações , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Convulsões/diagnóstico por imagem , Convulsões/etiologia , Anticonvulsivantes/uso terapêutico , Meios de Contraste , Eletroencefalografia , Feminino , Humanos , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , Convulsões/tratamento farmacológico
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