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1.
Int J Mol Sci ; 25(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38892447

RESUMO

Bisphenol-A (BPA), a synthetic compound ubiquitously present in the environment, can act as an endocrine disruptor by binding to both canonical and non-canonical estrogen receptors (ERs). Exposure to BPA has been linked to various cancers, in particular, those arising in hormone-targeted tissues such as the breast. In this study, we evaluated the effect of BPA intake through drinking water on ErbB2/neu-driven cancerogenesis in BALB-neuT mice, transgenic for a mutated ErbB2/neu receptor gene, which reproducibly develop carcinomas in all mammary glands. In this model, BPA accelerated mammary cancerogenesis with an increase in the number of tumors per mouse and a concurrent decrease in tumor-free and overall survival. As assessed by immunohistochemistry, BALB-neuT tumors were ER-negative but expressed high levels of the alternative estrogen receptor GPR30, regardless of BPA exposure. On the other hand, BPA exposure resulted in a marked upregulation of progesterone receptors in preinvasive tumors and of Ki67, CD31, and phosphorylated Akt in invasive tumors. Moreover, based on several infiltration markers of immune cells, BPA favored an immunosuppressive tumor microenvironment. Finally, in vitro cell survival studies performed on a cell line established from a BALB-neuT breast carcinoma confirmed that BPA's impact on cancer progression can be particularly relevant after chronic, low-dose exposure.


Assuntos
Compostos Benzidrílicos , Camundongos Endogâmicos BALB C , Fenóis , Receptores de Estrogênio , Microambiente Tumoral , Animais , Microambiente Tumoral/efeitos dos fármacos , Feminino , Camundongos , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Água Potável , Neoplasias Mamárias Experimentais/induzido quimicamente , Neoplasias Mamárias Experimentais/patologia , Neoplasias Mamárias Experimentais/metabolismo , Camundongos Transgênicos , Receptor ErbB-2/metabolismo , Receptor ErbB-2/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores de Progesterona/metabolismo , Receptores de Progesterona/genética , Carcinogênese/induzido quimicamente , Carcinogênese/efeitos dos fármacos , Disruptores Endócrinos/toxicidade
2.
Brain ; 145(8): 2687-2703, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-35675510

RESUMO

Vacuolar-type H+-ATPase (V-ATPase) is a multimeric complex present in a variety of cellular membranes that acts as an ATP-dependent proton pump and plays a key role in pH homeostasis and intracellular signalling pathways. In humans, 22 autosomal genes encode for a redundant set of subunits allowing the composition of diverse V-ATPase complexes with specific properties and expression. Sixteen subunits have been linked to human disease. Here we describe 26 patients harbouring 20 distinct pathogenic de novo missense ATP6V1A variants, mainly clustering within the ATP synthase α/ß family-nucleotide-binding domain. At a mean age of 7 years (extremes: 6 weeks, youngest deceased patient to 22 years, oldest patient) clinical pictures included early lethal encephalopathies with rapidly progressive massive brain atrophy, severe developmental epileptic encephalopathies and static intellectual disability with epilepsy. The first clinical manifestation was early hypotonia, in 70%; 81% developed epilepsy, manifested as developmental epileptic encephalopathies in 58% of the cohort and with infantile spasms in 62%; 63% of developmental epileptic encephalopathies failed to achieve any developmental, communicative or motor skills. Less severe outcomes were observed in 23% of patients who, at a mean age of 10 years and 6 months, exhibited moderate intellectual disability, with independent walking and variable epilepsy. None of the patients developed communicative language. Microcephaly (38%) and amelogenesis imperfecta/enamel dysplasia (42%) were additional clinical features. Brain MRI demonstrated hypomyelination and generalized atrophy in 68%. Atrophy was progressive in all eight individuals undergoing repeated MRIs. Fibroblasts of two patients with developmental epileptic encephalopathies showed decreased LAMP1 expression, Lysotracker staining and increased organelle pH, consistent with lysosomal impairment and loss of V-ATPase function. Fibroblasts of two patients with milder disease, exhibited a different phenotype with increased Lysotracker staining, decreased organelle pH and no significant modification in LAMP1 expression. Quantification of substrates for lysosomal enzymes in cellular extracts from four patients revealed discrete accumulation. Transmission electron microscopy of fibroblasts of four patients with variable severity and of induced pluripotent stem cell-derived neurons from two patients with developmental epileptic encephalopathies showed electron-dense inclusions, lipid droplets, osmiophilic material and lamellated membrane structures resembling phospholipids. Quantitative assessment in induced pluripotent stem cell-derived neurons identified significantly smaller lysosomes. ATP6V1A-related encephalopathy represents a new paradigm among lysosomal disorders. It results from a dysfunctional endo-lysosomal membrane protein causing altered pH homeostasis. Its pathophysiology implies intracellular accumulation of substrates whose composition remains unclear, and a combination of developmental brain abnormalities and neurodegenerative changes established during prenatal and early postanal development, whose severity is variably determined by specific pathogenic variants.


Assuntos
Encefalopatias , Epilepsia , Deficiência Intelectual , Espasmos Infantis , ATPases Vacuolares Próton-Translocadoras , Trifosfato de Adenosina , Atrofia , Criança , Homeostase , Humanos , Lactente , Lisossomos , Fenótipo
3.
Brain ; 145(1): 208-223, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-34382076

RESUMO

Subcellular membrane systems are highly enriched in dolichol, whose role in organelle homeostasis and endosomal-lysosomal pathway remains largely unclear besides being involved in protein glycosylation. DHDDS encodes for the catalytic subunit (DHDDS) of the enzyme cis-prenyltransferase (cis-PTase), involved in dolichol biosynthesis and dolichol-dependent protein glycosylation in the endoplasmic reticulum. An autosomal recessive form of retinitis pigmentosa (retinitis pigmentosa 59) has been associated with a recurrent DHDDS variant. Moreover, two recurring de novo substitutions were detected in a few cases presenting with neurodevelopmental disorder, epilepsy and movement disorder. We evaluated a large cohort of patients (n = 25) with de novo pathogenic variants in DHDDS and provided the first systematic description of the clinical features and long-term outcome of this new neurodevelopmental and neurodegenerative disorder. The functional impact of the identified variants was explored by yeast complementation system and enzymatic assay. Patients presented during infancy or childhood with a variable association of neurodevelopmental disorder, generalized epilepsy, action myoclonus/cortical tremor and ataxia. Later in the disease course, they experienced a slow neurological decline with the emergence of hyperkinetic and/or hypokinetic movement disorder, cognitive deterioration and psychiatric disturbances. Storage of lipidic material and altered lysosomes were detected in myelinated fibres and fibroblasts, suggesting a dysfunction of the lysosomal enzymatic scavenger machinery. Serum glycoprotein hypoglycosylation was not detected and, in contrast to retinitis pigmentosa and other congenital disorders of glycosylation involving dolichol metabolism, the urinary dolichol D18/D19 ratio was normal. Mapping the disease-causing variants into the protein structure revealed that most of them clustered around the active site of the DHDDS subunit. Functional studies using yeast complementation assay and in vitro activity measurements confirmed that these changes affected the catalytic activity of the cis-PTase and showed growth defect in yeast complementation system as compared with the wild-type enzyme and retinitis pigmentosa-associated protein. In conclusion, we characterized a distinctive neurodegenerative disorder due to de novo DHDDS variants, which clinically belongs to the spectrum of genetic progressive encephalopathies with myoclonus. Clinical and biochemical data from this cohort depicted a condition at the intersection of congenital disorders of glycosylation and inherited storage diseases with several features akin to of progressive myoclonus epilepsy such as neuronal ceroid lipofuscinosis and other lysosomal disorders.


Assuntos
Alquil e Aril Transferases , Mioclonia , Doenças Neurodegenerativas , Retinose Pigmentar , Criança , Dolicóis/metabolismo , Humanos , Doenças Neurodegenerativas/genética , Retinose Pigmentar/genética
4.
Int J Food Sci Nutr ; 74(7): 746-759, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37661348

RESUMO

Several attempts have been made to develop targeted therapies for malignant mesothelioma (MM), an aggressive tumour with a poor prognosis. In this study we evaluated whether Curcumin (CUR) potentiated the antitumor activity of the ErbB receptors inhibitor Afatinib (AFA) on MM, employing cell lines cultured in vitro and mice bearing intraperitoneally transplanted, syngeneic MM cells. The rationale behind this hypothesis was that CUR could counteract mechanisms of acquired resistance to AFA. We analysed CUR and AFA effects on MM cell growth, cell cycle, autophagy, and on the modulation of tumour-supporting signalling pathways.This study demonstrated that, as compared to the individual compounds, the combination of AFA + CUR had a stronger effect on MM progression which can be ascribed either to increased tumour cell growth inhibition or to an enhanced pro-apoptotic effect. These results warrant future studies aimed at further exploring the therapeutic potential of AFA + CUR-based combination regimens for MM treatment.


Assuntos
Curcumina , Mesotelioma Maligno , Camundongos , Animais , Afatinib/farmacologia , Receptores ErbB , Curcumina/farmacologia , Linhagem Celular Tumoral
5.
Int J Mol Sci ; 24(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37108403

RESUMO

The various immune effector cells that infiltrate the tumor microenvironment (TME) play a key role in directing the outcome of tumor growth [...].


Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/patologia , Imunoterapia
6.
Int J Mol Sci ; 25(1)2023 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-38203402

RESUMO

The polyphenols Curcumin (CUR) and Resveratrol (RES) are widely described for their antitumoral effects. However, their low bioavailability is a drawback for their use in therapy. The aim of this study was to explore whether CUR and RES, used at a bioavailable concentration, could modulate immune responses while retaining antitumor activity and to determine whether CUR and RES effects on the immune responses of peripheral blood mononuclear cells (PBMCs) and tumor growth inhibition could be improved by their combination. We demonstrate that the low-dose combination of CUR and RES reduced the survival of cancer cell lines but had no effect on the viability of PBMCs. Although following CUR + RES treatment T lymphocytes showed an enhanced activated state, RES counteracted the increased IFN-γ expression induced by CUR in T cells and the polyphenol combination increased IL-10 production by T regulatory cells. On the other hand, the combined treatment enhanced NK cell activity through the up- and downregulation of activating and inhibitory receptors and increased CD68 expression levels on monocytes/macrophages. Overall, our results indicate that the combination of CUR and RES at low doses differentially shapes immune cells while retaining antitumor activity, support the use of this polyphenol combinations in anticancer therapy and suggest its possible application as adjuvant for NK cell-based immunotherapies.


Assuntos
Curcumina , Neoplasias , Humanos , Resveratrol/farmacologia , Sobrevivência Celular , Curcumina/farmacologia , Leucócitos Mononucleares , Polifenóis/farmacologia , Neoplasias/tratamento farmacológico , Imunidade
7.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298418

RESUMO

Natural Killer (NK) cells are innate cytotoxic lymphoid cells that play a crucial role in cancer immunosurveillance. NKG2D is an activating receptor that binds to MIC and ULBP molecules typically induced on damaged, transformed, or infected cells. The secretion of NKG2D ligands (NKG2DLs) through protease-mediated cleavage or in an extracellular vesicle (EV) is a mode to control their cell surface expression and a mechanism used by cancer cells to evade NKG2D-mediated immunosurveillance. EVs are emerging as important players in mediating cell-to-cell communication due to their ability to transfer biological material to acceptor cells. Herein, we investigated the spreading of NKG2DLs of both MIC and ULBP molecules through the EV-mediated cross-dressing on multiple myeloma (MM) cells. We focused our attention on two MICA allelic variants, namely MICA*008 and MICA*019, representing the prototype of short and long MICA alleles, respectively, and on ULBP-1, ULBP-2, and ULBP-3. Our findings demonstrate that both ULBP and MICA ligands can be acquired from tumor cells through EVs enhancing NK cell recognition and killing. Moreover, besides MICA, EVs expressing ULBP-1 but not ULBP-2 and 3 were detected in bone marrow aspirates derived from a cohort of MM patients. Our findings shed light on the role of EV-associated MICA allelic variants and ULBP molecules in the modulation of NKG2D-mediated NK cell immunosurveillance in the tumor microenvironment. Moreover, the EV-mediated transfer of NKG2DLs could suggest novel therapeutic approaches based on the usage of engineered nanoparticles aimed at increasing cancer cell immunogenicity.


Assuntos
Vesículas Extracelulares , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/metabolismo , Ligantes , Subfamília K de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais , Vesículas Extracelulares/metabolismo , Morte Celular , Bandagens , Microambiente Tumoral
8.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37047835

RESUMO

The success of senescence-based anticancer therapies relies on their anti-proliferative power and on their ability to trigger anti-tumor immune responses. Indeed, genotoxic drug-induced senescence increases the expression of NK cell-activating ligands on multiple myeloma (MM) cells, boosting NK cell recognition and effector functions. Senescent cells undergo morphological change and context-dependent functional diversification, acquiring the ability to secrete a vast pool of molecules termed the senescence-associated secretory phenotype (SASP), which affects neighboring cells. Recently, exosomes have been recognized as SASP factors, contributing to modulating a variety of cell functions. In particular, evidence suggests a key role for exosomal microRNAs in influencing many hallmarks of cancer. Herein, we demonstrate that doxorubicin treatment of MM cells leads to the enrichment of miR-433 into exosomes, which in turn induces bystander senescence. Our analysis reveals that the establishment of the senescent phenotype on neighboring MM cells is p53- and p21-independent and is related to CDK-6 down-regulation. Notably, miR-433-dependent senescence does not induce the up-regulation of activating ligands on MM cells. Altogether, our findings highlight the possibility of miR-433-enriched exosomes to reinforce doxorubicin-mediated cellular senescence.


Assuntos
Antibióticos Antineoplásicos , Efeito Espectador , Senescência Celular , Doxorrubicina , Exossomos , MicroRNAs , Mieloma Múltiplo , Inibidores da Topoisomerase II , Senescência Celular/efeitos dos fármacos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Inibidores da Topoisomerase II/farmacologia , Inibidores da Topoisomerase II/uso terapêutico , Humanos , Linhagem Celular Tumoral , Exossomos/efeitos dos fármacos , Exossomos/metabolismo , Dano ao DNA , MicroRNAs/genética , MicroRNAs/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo
9.
Semin Cancer Biol ; 72: 65-75, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-31698088

RESUMO

Breast cancer is both the most common type of cancer and the most frequent cause of cancer mortality in women, mainly because of its heterogeneity and limited immunogenicity. The aim of specific active cancer immunotherapy is to stimulate the host's immune response against cancer cells directly using a vaccine platform carrying one or more tumor antigens. In particular, the ideal tumor antigen should be able to elicit T cell and B cell responses, be specific for the tumor and be expressed at high levels on cancer cells. Neoantigens are ideal targets for immunotherapy because they are exclusive to individual patient's tumors, are absent in healthy tissues and are not subject to immune tolerance mechanisms. Thus, neoantigens should generate a specific reaction towards tumors since they constitute the largest fraction of targets of tumor-infiltrating T cells. In this review, we describe the technologies used for neoantigen discovery, the heterogeneity of neoantigens in breast cancer and recent studies of breast cancer immunotherapy targeting neoantigens.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias da Mama/imunologia , Neoplasias da Mama/terapia , Vacinas Anticâncer/imunologia , Imunidade , Imunoterapia/métodos , Animais , Antígenos de Neoplasias/classificação , Neoplasias da Mama/genética , Vacinas Anticâncer/administração & dosagem , Feminino , Humanos , Mutação
10.
Hum Mutat ; 43(1): 67-73, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34747546

RESUMO

Biallelic mutations in the BRAT1 gene, encoding BRCA1-associated ATM activator 1, result in variable phenotypes, from rigidity and multifocal seizure syndrome, lethal neonatal to neurodevelopmental disorder, and cerebellar atrophy with or without seizures, without obvious genotype-phenotype associations. We describe two families at the mildest end of the spectrum, differing in clinical presentation despite a common genotype at the BRAT1 locus. Two siblings displayed nonprogressive congenital ataxia and shrunken cerebellum on magnetic resonance imaging. A third unrelated patient showed normal neurodevelopment, adolescence-onset seizures, and ataxia, shrunken cerebellum, and ultrastructural abnormalities on skin biopsy, representing the mildest form of NEDCAS hitherto described. Exome sequencing identified the c.638dup and the novel c.1395G>A BRAT1 variants, the latter causing exon 10 skippings. The p53-MCL test revealed normal ATM kinase activity. Our findings broaden the allelic and clinical spectrum of BRAT1-related disease, which should be suspected in presence of nonprogressive cerebellar signs, even without a neurodevelopmental disorder.


Assuntos
Proteínas Nucleares , Convulsões , Estudos de Associação Genética , Genótipo , Humanos , Mutação , Proteínas Nucleares/genética , Fenótipo , Convulsões/genética
11.
J Transl Med ; 20(1): 286, 2022 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-35752861

RESUMO

Malignant mesothelioma (MM) is a rare orphan aggressive neoplasia with low survival rates. Among the other signaling pathways, ErbB receptors and Hh signaling are deregulated in MM. Thus, molecules involved in these signaling pathways could be used for targeted therapy approaches. The aim of this study was to evaluate the effects of inhibitors of Hh- (GANT-61) and ErbB receptors (Afatinib)-mediated signaling pathways, when used alone or in combination, on growth, cell cycle, cell death and autophagy, modulation of molecules involved in transduction pathways, in three human MM cell lines of different histotypes. The efficacy of the combined treatment was also evaluated in a murine epithelioid MM cell line both in vitro and in vivo. This study demonstrated that combined treatment with two inhibitors counteracting the activation of two different signaling pathways involved in neoplastic transformation and progression, such as those activated by ErbB and Hh signaling, is more effective than the single treatments in reducing MM growth in vitro and in vivo. This study may have clinical implications for the development of targeted therapy approaches for MM.


Assuntos
Receptores ErbB , Mesotelioma Maligno , Animais , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Proteínas Hedgehog , Humanos , Camundongos , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco
12.
J Transl Med ; 20(1): 469, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243798

RESUMO

BACKGROUND: Melanoma is the deadliest form of skin cancer and metastatic disease is associated with a significant survival rate drop. There is an urgent need for consistent tumor biomarkers to scale precision medicine and reduce cancer mortality. Here, we aimed to identify a melanoma-specific circulating microRNA signature and assess its value as a diagnostic tool. METHODS: The study consisted of a discovery phase and two validation phases. Circulating plasma extracellular vesicles (pEV) associated microRNA profiles were obtained from a discovery cohort of metastatic melanoma patients and normal subjects as controls. A pEV-microRNA signature was obtained using a LASSO penalized logistic regression model. The pEV-microRNA signature was subsequently validated both in a publicly available dataset and in an independent internal cohort. RESULTS: We identified and validated in three independent cohorts a panel of melanoma-specific circulating microRNAs that showed high accuracy in differentiating melanoma patients from healthy subjects with an area under the curve (AUC) of 1.00, 0.94 and 0.75 respectively. Investigation of the function of the pEV-microRNA signature evidenced their possible immune suppressive role in melanoma patients. CONCLUSIONS: We demonstrate that a blood test based on circulating microRNAs can non-invasively detect melanoma, offering a novel diagnostic tool for improving standard care. Moreover, we revealed an immune suppressive role for melanoma pEV-microRNAs.


Assuntos
MicroRNA Circulante , Melanoma , MicroRNAs , Biomarcadores Tumorais/genética , MicroRNA Circulante/genética , Perfilação da Expressão Gênica , Humanos , Biópsia Líquida , Melanoma/diagnóstico , Melanoma/genética , MicroRNAs/genética
13.
Int J Mol Sci ; 22(12)2021 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-34202978

RESUMO

Niemann-Pick type C (NPC) disease is an autosomal recessive storage disorder, characterized by abnormal sequestration of unesterified cholesterol in the late endo-lysosomal system of cells. Progressive neurological deterioration and the onset of symptoms, such as ataxia, seizures, cognitive decline, and severe dementia, are pathognomonic features of the disease. In addition, different pathological similarities, including degeneration of hippocampal and cortical neurons, hyperphosphorylated tau, and neurofibrillary tangle formation, have been identified between NPC disease and other neurodegenerative pathologies. However, the underlying pathophysiological mechanisms are not yet well understood, and even a real cure to counteract neurodegeneration has not been identified. Therefore, the combination of current pharmacological therapies, represented by miglustat and cyclodextrin, and non-pharmacological approaches, such as physical exercise and appropriate diet, could represent a strategy to improve the quality of life of NPC patients. Based on this evidence, in our review we focused on the neurodegenerative aspects of NPC disease, summarizing the current knowledge on the molecular and biochemical mechanisms responsible for cognitive impairment, and suggesting physical exercise and nutritional treatments as additional non-pharmacologic approaches to reduce the progression and neurodegenerative course of NPC disease.


Assuntos
Suscetibilidade a Doenças , Degeneração Neural/etiologia , Doença de Niemann-Pick Tipo C/etiologia , Doença de Niemann-Pick Tipo C/terapia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Tomada de Decisão Clínica , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/terapia , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Gerenciamento Clínico , Humanos , Degeneração Neural/diagnóstico , Doença de Niemann-Pick Tipo C/diagnóstico , Doença de Niemann-Pick Tipo C/tratamento farmacológico , Resultado do Tratamento
14.
Invest New Drugs ; 38(3): 675-689, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31264066

RESUMO

Osteosarcoma (OS) is the most common primary malignant bone tumor and mainly affects children and adolescents. The OS five-year survival rate remains very low. Thus, novel therapeutic protocols for the treatment of OS are needed. Several approaches targeting deregulated signaling pathways have been proposed. The antitumoral effects of polyphenols, which are naturally occurring compounds with potent antioxidant and anti-inflammatory activity, have been investigated in different tumors. Gossypol, which is a natural polyphenolic aldehyde isolated from the seeds of the cotton plant, has been shown to exert antitumoral activity in leukemia and lymphoma and in breast, head and neck, colon and prostate cancers. Therefore, in this study, we evaluated the effect of AT-101, which is the (-) enantiomer and more active form of gossypol, on the growth of human and murine OS cells in vitro and in vivo. Several clinical trials employing AT-101 have been performed, and some clinical trials are ongoing. Our results showed for the first time that AT-101 significantly inhibits OS cell growth in a dose- and time-dependent manner, inducing apoptosis and necrosis and partially activating autophagy. Our results demonstrated that AT-101 inhibits prosurvival signaling pathways depending on Akt, p38 MAPK and JNK. In addition, treatment with AT-101 increases the survival of OS-bearing mice. Overall, these results suggest that AT-101 is a candidate chemo-supportive molecule for the development of novel chemotherapeutic protocols for the treatment of OS.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Gossipol/análogos & derivados , Osteossarcoma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Gossipol/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Osteossarcoma/metabolismo , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Int J Mol Sci ; 21(19)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992895

RESUMO

The increasing exposure to radiofrequency electromagnetic fields (RF-EMF), especially from wireless communication devices, raises questions about their possible adverse health effects. So far, several in vitro studies evaluating RF-EMF genotoxic and cytotoxic non-thermal effects have reported contradictory results that could be mainly due to inadequate experimental design and lack of well-characterized exposure systems and conditions. Moreover, a topic poorly investigated is related to signal modulation induced by electromagnetic fields. The aim of this study was to perform an analysis of the potential non-thermal biological effects induced by 2.45 GHz exposures through a characterized exposure system and a multimethodological approach. Human fibroblasts were exposed to continuous (CW) and pulsed (PW) signals for 2 h in a wire patch cell-based exposure system at the specific absorption rate (SAR) of 0.7 W/kg. The evaluation of the potential biological effects was carried out through a multimethodological approach, including classical biological markers (genotoxic, cell cycle, and ultrastructural) and the evaluation of gene expression profile through the powerful high-throughput next generation sequencing (NGS) RNA sequencing (RNA-seq) approach. Our results suggest that 2.45 GHz radiofrequency fields did not induce significant biological effects at a cellular or molecular level for the evaluated exposure parameters and conditions.


Assuntos
Ciclo Celular/efeitos da radiação , Derme/efeitos da radiação , Fibroblastos/efeitos da radiação , Expressão Gênica/efeitos da radiação , Ondas de Rádio/efeitos adversos , Idoso , Células Cultivadas , Derme/citologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Int J Mol Sci ; 21(18)2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32927836

RESUMO

One of the hallmarks of cellular transformation is the altered mechanism of cell death. There are three main types of cell death, characterized by different morphological and biochemical features, namely apoptosis (type I), autophagic cell death (type II) and necrosis (type III). Autophagy, or self-eating, is a tightly regulated process involved in stress responses, and it is a lysosomal degradation process. The role of autophagy in cancer is controversial and has been associated with both the induction and the inhibition of tumor growth. Autophagy can exert tumor suppression through the degradation of oncogenic proteins, suppression of inflammation, chronic tissue damage and ultimately by preventing mutations and genetic instability. On the other hand, tumor cells activate autophagy for survival in cellular stress conditions. Thus, autophagy modulation could represent a promising therapeutic strategy for cancer. Several studies have shown that polyphenols, natural compounds found in foods and beverages of plant origin, can efficiently modulate autophagy in several types of cancer. In this review, we summarize the current knowledge on the effects of polyphenols on autophagy, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of polyphenols for envisioning future therapies employing polyphenols as chemoadjuvants.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Polifenóis/uso terapêutico , Animais , Humanos , Polifenóis/farmacologia
17.
J Gen Virol ; 100(1): 89-98, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30427305

RESUMO

Herpesviruses are known to manipulate autophagy to optimize their replication, counteract immune response and probably to promote tumourigenesis. This study explored, for the first time, the impact of human herpesvirus (HHV)-6 lytic infection on autophagy and demonstrated that HHV-6A and B (viruses sharing more than 80 % homology) differently affected this cellular process. Indeed, while HHV-6A (GS) infection of HSB2 cells promoted autophagy, HHV-6B (Z29) or the virus isolated from the serum of roseola infantum-affected patient-inhibited autophagy in Molt-3 cells or in PBMCs, respectively. Interestingly, the different behaviour of HHV-6A and B on the autophagic process was accompanied by different effects on endoplasmic reticulum stress, unfolded protein response and cell survival that was more strongly reduced by HHV-6B infection. We hypothesize that the ability to inhibit autophagy displayed by HHV-6B could be due to the fact that it contains gene homologues of those encoding for TRS1; the protein responsible for the block of autophagy by human cytomegalovirus. Understanding how HHV-6A/B infection regulates autophagy could be of particular interest, as it has been recently shown that this virus may be involved in Alzheimer's disease in which a dysregulation of autophagy may also play a role.


Assuntos
Autofagia , Estresse do Retículo Endoplasmático , Herpesvirus Humano 6/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Linhagem Celular , Genótipo , Herpesvirus Humano 6/genética , Humanos , Linfócitos T/patologia , Linfócitos T/virologia
19.
Hum Mol Genet ; 24(24): 6921-31, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26410888

RESUMO

Leber's hereditary optic neuropathy (LHON) is a maternally inherited blinding disease characterized by degeneration of retinal ganglion cells (RGCs) and consequent optic nerve atrophy. Peculiar features of LHON are incomplete penetrance and gender bias, with a marked male prevalence. Based on the different hormonal metabolism between genders, we proposed that estrogens play a protective role in females and showed that these hormones ameliorate mitochondrial dysfunction in LHON through the estrogen receptors (ERs). We also showed that ERß localize to the mitochondria of RGCs. Thus, targeting ERß may become a therapeutic strategy for LHON specifically aimed at avoiding or delaying the onset of disease in mutation carriers. Here, we tested the effects of ERß targeting on LHON mitochondrial defective metabolism by treating LHON cybrid cells carrying the m.11778G>A mutation with a combination of natural estrogen-like compounds that bind ERß with high selectivity. We demonstrated that these molecules improve cell viability by reducing apoptosis, inducing mitochondrial biogenesis and strongly reducing the levels of reactive oxygen species in LHON cells. These effects were abolished in cells with ERß knockdown by silencing receptor expression or by using specific receptor antagonists. Our observations support the hypothesis that estrogen-like molecules may be useful in LHON prophylactic therapy. This is particularly important for lifelong disease prevention in unaffected LHON mutation carriers. Current strategies attempting to combat degeneration of RGCs during the acute phase of LHON have not been very effective. Implementing a different and preemptive approach with a low risk profile may be very helpful.


Assuntos
Receptor beta de Estrogênio/antagonistas & inibidores , Atrofia Óptica Hereditária de Leber/prevenção & controle , Fitoestrógenos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Respiração Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Receptor beta de Estrogênio/genética , Feminino , Técnicas de Silenciamento de Genes , Humanos , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mutação , Atrofia Óptica Hereditária de Leber/metabolismo , Biogênese de Organelas , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio , Células Ganglionares da Retina/metabolismo
20.
Int J Food Sci Nutr ; 68(3): 298-312, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27670669

RESUMO

Racemic Gossypol [(±)-GOS], composed of both (-)-GOS and (+)-GOS, is a small BH3-mimetic polyphenol derived from cotton seeds. (±)-GOS has been employed and well tolerated by cancer patients. Head and neck carcinoma (HNC) represents one of the most fatal cancers worldwide, and a significant proportion of HNC expresses high levels of antiapoptotic Bcl-2 proteins. In this study, we demonstrate that (±)-GOS inhibits cell proliferation and induces apoptosis and autophagy of human pharynx, tongue, and salivary gland cancer cell lines and of mouse salivary gland cancer cells (SALTO). (±)-GOS was able to: (a) decrease the ErbB2 protein expression; (b) inhibit the phosphorylation of ERK1/2 and AKT; (c) stimulate p38 and JNK1/2 protein phosphorylation. (±)-GOS administration was safe in BALB/c mice and it reduced the growth of transplanted SALTO cells in vivo and prolonged mice median survival. Our results suggest the potential role of (±)-GOS as an antitumor agent in HNC patients.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Gossipol/farmacologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias das Glândulas Salivares/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação da Expressão Gênica , Genes erbB-2 , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Neoplasias das Glândulas Salivares/patologia , Transdução de Sinais
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