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1.
Int J Mol Sci ; 22(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34769261

RESUMO

Obesity is a complex disease caused by an excessive amount of body fat. Obesity is a medical problem and represents an important risk factor for the development of serious diseases such as insulin resistance, type 2 diabetes, cardiovascular disease, and some types of cancer. Not to be overlooked are the psychological issues that, in obese subjects, turn into very serious pathologies, such as depression, phobias, anxiety, and lack of self-esteem. In addition to modifying one's lifestyle, the reduction of body mass can be promoted by different natural compounds such as essential oils (EOs). EOs are mixtures of aromatic substances produced by many plants, particularly in medicinal and aromatic ones. They are odorous and volatile and contain a mixture of terpenes, alcohols, aldehydes, ketones, and esters. Thanks to the characteristics of the various chemical components present in them, EOs are used in the food, cosmetic, and pharmaceutical fields. Indeed, it has been shown that EOs possess great antibiotic, anti-inflammatory, and antitumor powers. Emerging results also demonstrate the anti-obesity effects of EOs. We have examined the main data obtained in experimental studies and, in this review, we summarize the effect of EOs in obesity and obesity-related metabolic diseases.

2.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360732

RESUMO

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a well-known transcription factor best recognised as one of the main regulators of the oxidative stress response. Beyond playing a crucial role in cell defence by transactivating cytoprotective genes encoding antioxidant and detoxifying enzymes, Nrf2 is also implicated in a wide network regulating anti-inflammatory response and metabolic reprogramming. Such a broad spectrum of actions renders the factor a key regulator of cell fate and a strategic player in the control of cell transformation and response to viral infections. The Nrf2 protective roles in normal cells account for its anti-tumour and anti-viral functions. However, Nrf2 overstimulation often occurs in tumour cells and a complex correlation of Nrf2 with cancer initiation and progression has been widely described. Therefore, if on one hand, Nrf2 has a dual role in cancer, on the other hand, the factor seems to display a univocal function in preventing inflammation and cytokine storm that occur under viral infections, specifically in coronavirus disease 19 (COVID-19). In such a variegate context, the present review aims to dissect the roles of Nrf2 in both cancer and COVID-19, two widespread diseases that represent a cause of major concern today. In particular, the review describes the molecular aspects of Nrf2 signalling in both pathological situations and the most recent findings about the advantages of Nrf2 inhibition or activation as possible strategies for cancer and COVID-19 treatment respectively.


Assuntos
COVID-19/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Neoplasias/metabolismo , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Antioxidantes/química , Antioxidantes/metabolismo , COVID-19/tratamento farmacológico , Humanos , Fator 2 Relacionado a NF-E2/química , Neoplasias/tratamento farmacológico , Transdução de Sinais
3.
Molecules ; 26(14)2021 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-34299603

RESUMO

Today, an improved understanding of cancer cell response to cellular stress has become more necessary. Indeed, targeting the intracellular pro-oxidant/antioxidant balance triggering the tumor commitment to cell demise could represent an advantageous strategy to develop cancer-tailored therapies. In this scenario, the present study shows how the peel extract of mango-a tropical fruit rich in phytochemicals with nutraceutical properties-can affect the cell viability of three colon cancer cell lines (HT29, Caco-2 and HCT116), inducing an imbalance of cellular redox responses. By using hydro-alcoholic mango peel extract (MPE), we observed a consistent decline in thiol group content, which was accompanied by upregulation of MnSOD-a mitochondrial scavenger enzyme that modulates the cellular response against oxidative damage. Such an effect was the consequence of an early production of mitochondrial superoxide anions that appeared after just 30 min of exposure of colon cancer cells to MPE. The effect was accompanied by mitochondrial injury, consisting of the dissipation of mitochondrial membrane potential and a decrease in the level of proteins localized in the mitochondrial membrane-such as voltage-dependent anion-selective channel (VDAC1), mitofilin, and some members of Bcl-2 family proteins (Mcl-1, Bcl-2 and Bcl-XL)-with the mitochondrial release of apoptogenic factors (cytochrome C and AIF). The analysis of the cytotoxic effects exerted by the different constituents of MPE (gallic acid, mangiferin, citric acid, quinic acid, pentagalloyl glucose, and methyl gallate) allowed us to identify those phytochemicals responsible for the observed anticancer effects, sustaining their future employment as chemopreventive or therapeutic agents.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Mangifera , Mitocôndrias/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Mangifera/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias/metabolismo , Neoplasias/patologia , Oxirredução/efeitos dos fármacos , Extratos Vegetais/química
4.
Int J Mol Sci ; 21(21)2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-33143349

RESUMO

Organotin compounds represent potential cancer therapeutics due to their pro-apoptotic action. We recently synthesized the novel organotin ferulic acid derivative tributyltin (IV) ferulate (TBT-F) and demonstrated that it displays anti-tumor properties in colon cancer cells related with autophagic cell death. The purpose of the present study was to elucidate the mechanism of TBT-F action in colon cancer cells. We specifically show that TBT-F-dependent autophagy is determined by a rapid generation of reactive oxygen species (ROS) and correlated with endoplasmic reticulum (ER) stress. TBT-F evoked nuclear factor erythroid-2 related factor 2 (Nrf2)-mediated antioxidant response and Nrf2 silencing by RNA interference markedly increased the anti-tumor efficacy of the compound. Moreover, as a consequence of ROS production, TBT-F increased the levels of glucose regulated protein 78 (Grp78) and C/EBP homologous protein (CHOP), two ER stress markers. Interestingly, Grp78 silencing produced significant decreasing effects on the levels of the autophagic proteins p62 and LC3-II, while only p62 decreased in CHOP-silenced cells. Taken together, these results indicate that ROS-dependent ER stress and autophagy play a major role in the TBT-F action mechanism in colon cancer cells and open a new perspective to consider the compound as a potential candidate for colon cancer treatment.


Assuntos
Autofagia , Neoplasias do Colo/tratamento farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Compostos de Trialquitina/farmacologia , Apoptose , Proliferação de Células , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Fator 2 Relacionado a NF-E2/genética , Células Tumorais Cultivadas
5.
Healthcare (Basel) ; 8(4)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066519

RESUMO

A lifelong adherence to a gluten-free (GF) diet is currently the only treatment for Celiac disease (CD), an autoimmune disorder that arises after gluten ingestion in individuals who are genetically predisposed. The gluten intake exerts toxic effects through several pathways involving gut barrier integrity, intestinal microbiota composition and immune system stimulation. However, despite the great benefit of GF diet for CD patients, its use has been debated. Indeed, individuals who adopt this diet regime may be at risk of nutrient deficiencies. Emerging evidence supports a beneficial effect of a GF diet also for other pathological conditions, including gluten-related disorders (GRD) often associated to CD, such as Non celiac gluten sensitivity (NCGS) and Dermatitis Herpetiforme (DH) as well as Irritable bowel syndrome (IBS) and Diabetes. This suggests a pathogenic role of gluten in these conditions. Despite the growing popularity of GF diet among consumers, to date, there are limited evidences supporting its use for the management of non-celiac diseases. Therefore, in this review, we discuss whether the GF diet could really improve the general quality of life of patients with GRD and non-GRD conditions, keeping in mind its sensorial limitations and nutritional inadequacies. In addition, we discuss the current motivations, leading to the use of a GF diet, despite the inferior quality of GF products respect to those containing gluten.

6.
Cell Stress Chaperones ; 25(6): 805-820, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32856199

RESUMO

Fatty acid-binding proteins (FABPs) are lipid chaperones assisting in the trafficking of long-chain fatty acids with functions in various cell compartments, including oxidation, signaling, gene-transcription regulation, and storage. The various known FABP isoforms display distinctive tissue distribution, but some are active in more than one tissue. Quantitative and/or qualitative changes of FABPs are associated with pathological conditions. Increased circulating levels of FABPs are biomarkers of disorders such as obesity, insulin resistance, cardiovascular disease, and cancer. Deregulated expression and malfunction of FABPs can result from genetic alterations or posttranslational modifications and can be pathogenic. We have assembled the disorders with abnormal FABPs as chaperonopathies in a distinct nosological entity. This entity is similar but separate from that encompassing the chaperonopathies pertaining to protein chaperones. In this review, we discuss the role of FABPs in the pathogenesis of metabolic syndrome, cancer, and neurological diseases. We highlight the opportunities for improving diagnosis and treatment that open by encompassing all these pathological conditions within of a coherent nosological group, focusing on abnormal lipid chaperones as biomarkers of disease and etiological-pathogenic factors.


Assuntos
Pesquisa Biomédica , Doença , Lipídeos/química , Chaperonas Moleculares/metabolismo , Animais , Proteínas de Ligação a Ácido Graxo/metabolismo , Humanos , Modelos Biológicos
7.
Brain Sci ; 10(7)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659996

RESUMO

Celiac Disease (CD) is an immune-mediated disease triggered by the ingestion of wheat gliadin and related prolamins from other cereals, such as barley and rye. Immunity against these cereal-derived proteins is mediated by pro-inflammatory cytokines produced by both innate and adaptive system response in individuals unable to adequately digest them. Peptides generated in this condition are absorbed across the gut barrier, which in these patients is characterized by the deregulation of its permeability. Here, we discuss a possible correlation between CD and Autistic Spectrum Disorder (ASD) pathogenesis. ASD can be induced by an excessive and inappropriate brain opioid activity during the neonatal period. Cereal-derived peptides produced in celiac patients cross the blood-brain barrier and bind to endogenous opioid receptors interfering with neurotransmission and generating deleterious effects on brain maturation, learning and social relations. Moreover, an increase in oxidative stress and a decrease in the antioxidant capacity, as well as an extended mitochondrial impairment in the brain, could represent a possible connection between ASD and CD. Therefore, we critically discuss the proposed relationship between ASD and CD and the possible usefulness of a gluten-free diet in ASD patients.

8.
Int J Mol Sci ; 21(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708719

RESUMO

p62 is a versatile protein involved in the delicate balance between cell death and survival, which is fundamental for cell fate decision in the context of both cancer and neurodegenerative diseases. As an autophagy adaptor, p62 recognizes polyubiquitin chains and interacts with LC3, thereby targeting the selected cargo to the autophagosome with consequent autophagic degradation. Beside this function, p62 behaves as an interactive hub in multiple signalling including those mediated by Nrf2, NF-κB, caspase-8, and mTORC1. The protein is thus crucial for the control of oxidative stress, inflammation and cell survival, apoptosis, and metabolic reprogramming, respectively. As a multifunctional protein, p62 falls into the category of those factors that can exert opposite roles in the cells. Chronic p62 accumulation was found in many types of tumors as well as in stress granules present in different forms of neurodegenerative diseases. However, the protein seems to have a Janus behaviour since it may also serve protective functions against tumorigenesis or neurodegeneration. This review describes the diversified roles of p62 through its multiple domains and interactors and specifically focuses on its oncoJanus and neuroJanus roles.


Assuntos
Neoplasias/metabolismo , Doenças Neurodegenerativas/metabolismo , Proteína Sequestossoma-1/metabolismo , Animais , Apoptose , Autofagia , Humanos , Estresse Oxidativo , Transdução de Sinais
9.
Antioxidants (Basel) ; 8(10)2019 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-31546694

RESUMO

Ethanolic extracts from Mangifera indica L. have been proved to possess anti-tumor properties in many cancer systems. However, although most effects have been demonstrated with fruit pulp extract, the underlying molecular mechanisms of mango peel are still unclear. This study was designed to explore the effects of mango peel extract (MPE) on colon cancer cell lines. MPE affected cell viability and inhibited the colony formation trend of tumor cells, while no effects were observed in human dermal fibroblasts used as a non-cancerous cell line model. These events were a consequence of the induction of apoptosis associated to reactive oxygen species (ROS) production, activation of players of the oxidative response such as JNK and ERK1/2, and the increase in Nrf2 and manganese superoxide dismutase (MnSOD). Significantly, mango peel-activated stress triggered a DNA damage response evidenced by the precocious phosphorylation of histone 2AX (γH2AX), as well as phosphorylated Ataxia telangiectasia-mutated (ATM) kinase and p53 upregulation. Mango peel extract was also characterized, and HPLC/MS (High Performance Liquid Chromatography/Mass Spectrometry) analysis unveiled the presence of some phenolic compounds that could be responsible for the anti-cancer effects. Collectively, these findings point out the importance of the genotoxic stress signaling pathway mediated by γH2AX in targeting colon tumor cells to apoptosis.

10.
Cancers (Basel) ; 11(4)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974805

RESUMO

Epidemiological studies suggest that chronic alcohol consumption is a lifestyle risk factor strongly associated with colorectal cancer development and progression. The aim of the present study was to examine the effect of ethanol (EtOH) on survival and progression of three different colon cancer cell lines (HCT116, HT29, and Caco-2). Our data showed that EtOH induces oxidative and endoplasmic reticulum (ER) stress, as demonstrated by reactive oxygen species (ROS) and ER stress markers Grp78, ATF6, PERK and, CHOP increase. Moreover, EtOH triggers an autophagic response which is accompanied by the upregulation of beclin, LC3-II, ATG7, and p62 proteins. The addition of the antioxidant N-acetylcysteine significantly prevents autophagy, suggesting that autophagy is triggered by oxidative stress as a prosurvival response. EtOH treatment also upregulates the antioxidant enzymes SOD, catalase, and heme oxygenase (HO-1) and promotes the nuclear translocation of both Nrf2 and HO-1. Interestingly, EtOH also upregulates the levels of matrix metalloproteases (MMP2 and MMP9) and VEGF. Nrf2 silencing or preventing HO-1 nuclear translocation by the protease inhibitor E64d abrogates the EtOH-induced increase in the antioxidant enzyme levels as well as the migration markers. Taken together, our results suggest that EtOH mediates both the activation of Nrf2 and HO-1 to sustain colon cancer cell survival, thus leading to the acquisition of a more aggressive phenotype.

11.
Int J Mol Sci ; 20(2)2019 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-30669512

RESUMO

Extracellular vesicles (EVs), including exosomes, are membranous particles released by cells into the extracellular space. They are involved in cell differentiation, tissue homeostasis, and organ remodelling in virtually all tissues, including the central nervous system (CNS). They are secreted by a range of cell types and via blood reaching other cells whose functioning they can modify because they transport and deliver active molecules, such as proteins of various types and functions, lipids, DNA, and miRNAs. Since they are relatively easy to isolate, exosomes can be characterized, and their composition elucidated and manipulated by bioengineering techniques. Consequently, exosomes appear as promising theranostics elements, applicable to accurately diagnosing pathological conditions, and assessing prognosis and response to treatment in a variety of disorders. Likewise, the characteristics and manageability of exosomes make them potential candidates for delivering selected molecules, e.g., therapeutic drugs, to specific target tissues. All these possible applications are pertinent to research in neurophysiology, as well as to the study of neurological disorders, including CNS tumors, and autoimmune and neurodegenerative diseases. In this brief review, we discuss what is known about the role and potential future applications of exosomes in the nervous system and its diseases, focusing on cell⁻cell communication in physiology and pathology.


Assuntos
Sistema Nervoso Central/fisiologia , Vesículas Extracelulares/fisiologia , Doenças Neurodegenerativas/terapia , Comunicação Celular , Diferenciação Celular , Portadores de Fármacos , Exossomos/fisiologia , Humanos , Nanomedicina Teranóstica
12.
Oncotarget ; 8(17): 28939-28958, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28423652

RESUMO

MiR-29 family dysregulation occurs in various cancers including breast cancers. We investigated miR-29b-1 functional role in human triple negative breast cancer (TNBC) the most aggressive breast cancer subtype. We found that miR-29b-1-5p was downregulated in human TNBC tissues and cell lines. To assess whether miR-29b-1-5p correlated with TNBC regenerative potential, we evaluated cancer stem cell enrichment in our TNBC cell lines, and found that only MDA-MB-231 and BT-20 produced primary, secondary and tertiary mammospheres, which were progressively enriched in OCT4, NANOG and SOX2 stemness genes. MiR-29b-1-5p expression inversely correlated with mammosphere stemness potential, and miR-29b-1 ectopic overexpression decreased TNBC cell growth, self-renewal, migration, invasiveness and paclitaxel resistance repressing WNT/ßcatenin and AKT signaling pathways and stemness regulators. We identified SPINDLIN1 (SPIN1) among predicted miR-29b-1-5p targets. Consistently, SPIN1 was overexpressed in most TNBC tissues and cell lines and negatively correlated with miR-29b-1-5p. Target site inhibition showed that SPIN1 seems to be directly controlled by miR-29b-1-5p. Silencing SPIN1 mirrored the effects triggered by miR-29b-1 overexpression, whereas SPIN1 rescue by SPIN1miScript protector, determined the reversal of the molecular effects produced by the mimic-miR-29b-1-5p. Overall, we show that miR-29b-1 deregulation impacts on multiple oncogenic features of TNBC cells and their renewal potential, acting, at least partly, through SPIN1, and suggest that both these factors should be evaluated as new possible therapeutic targets against TNBC.


Assuntos
Proteínas de Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Fosfoproteínas/genética , Transdução de Sinais/genética , Neoplasias de Mama Triplo Negativas/genética , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Mama/patologia , Carcinogênese/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , MicroRNAs/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Proteína Homeobox Nanog/metabolismo , Invasividade Neoplásica/genética , Células-Tronco Neoplásicas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Fosfoproteínas/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia
13.
Cell Death Discov ; 3: 17078, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29354292

RESUMO

Triple-negative breast cancer is a group of aggressive cancers with poor prognosis owing to chemoresistance, recurrence and metastasis. New strategies are required that could reduce chemoresistance and increases the effectiveness of chemotherapy. The results presented in this paper, showing that parthenolide (PN) prevents drug resistance in MDA-MB231 cells, represent a contribution to one of these possible strategies. MDA-MB231 cells, the most studied line of TNBC cells, were submitted to selection treatment with mitoxantrone (Mitox) and doxorubicin (DOX). The presence of resistant cells was confirmed through the measurement of the resistance index. Cells submitted to this treatment exhibited a remarkable increment of NF-E2-related factor 2 (Nrf2) level, which was accompanied by upregulation of catalase, MnSOD, HSP70, Bcl-2 and P-glycoprotein. Moreover, as a consequence of overexpression of Nrf2 and correlated proteins, drug-treated cells exhibited a much lower ability than parental cells to generate ROS in response to a suitable stimulation. The addition of PN (2.0 µM) to Mitox and DOX, over the total selection time, prevented both the induction of resistance and the overexpression of Nrf2 and correlated proteins, whereas the cells showed a good ability to generate ROS in response to adequate stimulation. To demonstrate that Nrf2 exerted a crucial role in the induction of resistance, the cells were transiently transfected with a specific small interfering RNA for Nrf2. Similarly to the effects induced by PN, downregulation of Nrf2 was accompanied by reductions in the levels of catalase, MnSOD, HSP70 and Bcl-2, prevention of chemoresistance and increased ability to generate ROS under stimulation. In conclusion, our results show that PN inhibited the development of the resistance toward Mitox and DOX, and suggest that these effects were correlated with the prevention of the overexpression of Nrf2 and its target proteins, which occurred in the cells submitted to drug treatment.

14.
Int J Oncol ; 48(6): 2339-48, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27082853

RESUMO

Triple-negative breast cancer (TNBC) is a clinically aggressive form of breast cancer that is unresponsive to endocrine agents or trastuzumab. TNBC accounts for ~10-20% of all breast cancer cases and represents the form with the poorest prognosis. Patients with TNBC are at higher risk of early recurrence, mainly in the lungs, brain and soft tissue, therefore, there is an urgent need for new therapies. The present study was carried out in MDA-MB-231 cells, where we assessed the role of caspase-8 (casp-8), a critical effector of death receptors, also involved in non­apoptotic functions. Analysis of casp-8 mRNA and protein levels indicated that they were up-regulated with respect to the normal human mammalian epithelial cells. We demonstrated that silencing of casp-8 by small interfering-RNA, strongly decreased MDA-MB-231 cell growth by delaying G0/G1- to S-phase transition and increasing p21, p27 and hypo-phosphorylated/active form of pRb levels. Surprisingly, casp-8-knockdown, also potently increased both the migratory and metastatic capacity of MDA-MB­231 cells, as shown by both wound healing and Matrigel assay, and by the expression of a number of related-genes and/or proteins such as VEGFA, C-MYC, CTNNB1, HMGA2, CXCR4, KLF4, VERSICAN V1 and MMP2. Among these, KLF4, a transcriptional factor with a dual role (activator and repressor), seemed to play critical roles. We suggest that in MDA-MB­231 cells, the endogenous expression of casp-8 might keep the cells perpetually cycling through downregulation of KLF4, the subsequent lowering of p21 and p27, and the inactivation by hyperphosphorylation of pRb. Simultaneously, by lowering the expression of some migratory and invasive genes, casp-8 might restrain the metastatic ability of the cells. Overall, our findings showed that, in MDA-MB-231 cells, casp-8 might play some unusual roles which should be better explored, in order to understand whether it might be identified as a molecular therapeutic target.


Assuntos
Caspase 8/metabolismo , Neoplasias de Mama Triplo Negativas/enzimologia , Caspase 8/genética , Ciclo Celular/fisiologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Fase G1/fisiologia , Humanos , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Fase de Repouso do Ciclo Celular/fisiologia , Transfecção , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
15.
Int J Oncol ; 49(1): 352-60, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27121069

RESUMO

Breast cancer stem cells seem to play important roles in breast tumor recurrence and endocrine therapy resistance, although the underlying mechanisms have not been well established. Moreover, in some tumor systems the immunosurveillance failure against cancer cells has been related to the presence of the granzyme B inhibitor PI-9. This study explored the status of PI-9 in tumorspheres isolated from estrogen receptor-α positive (ERα+) breast cancer MCF7 cells. Studies were performed in tertiary tumorspheres which possess high levels of stemness markers (Nanog, Oct3/4 and Sox2) and self-renewal ability. The exposure to estrogens (17-ß estradiol and genistein) increased the number and sizes of tumorspheres, promoting cell proliferation as demonstrated by the increase in the proliferating cell nuclear antigen (PCNA). The study of the three isoforms (66, 46 and 36 kDa) of ERα disclosed that tertiary tumorspheres exhibit a marked increase in ERα36, while the level of ERα66, which is highly expressed in MCF7 cells, declines. Although it is known that PI-9 is a transcriptional target of ERα66, surprisingly in tertiary tumorspheres, despite the reduced level of ERα66, the protein and mRNA content of PI-9 is higher than in MCF7 cells. Treatment with estrogens further increased PI-9 level while decreased that of ERα66 isoform thus excluding the involvement of this receptor isoform in the event. Moreover, our studies also provided evidence that tertiary tumorspheres express elevated levels of CXCR4 and phospho-p38, suggesting that the high PI-9 content might be ascribed to the activation of the proliferative CXCR4/phospho-p38 axis. Taken together, these events could supply a selective advantage to breast cancer stem cells by interfering with immunosurveillance systems and open up the avenue to new possible targets for breast cancer treatment.


Assuntos
Neoplasias da Mama/genética , Receptor alfa de Estrogênio/biossíntese , Recidiva Local de Neoplasia/genética , Células-Tronco Neoplásicas/metabolismo , Serpinas/biossíntese , Neoplasias da Mama/patologia , Proliferação de Células/genética , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genisteína/administração & dosagem , Granzimas/antagonistas & inibidores , Humanos , Células MCF-7 , Recidiva Local de Neoplasia/fisiopatologia , Células-Tronco Neoplásicas/patologia , Receptores CXCR4/biossíntese , Serpinas/genética , Transdução de Sinais/efeitos dos fármacos , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese
16.
J Cell Physiol ; 231(8): 1832-41, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26679758

RESUMO

Osteosarcoma (OS), an aggressive highly invasive and metastatic bone-malignancy, shows therapy resistance and recurrence, two features that likely depend on cancer stem cells (CSCs), which hold both self-renewing and malignant potential. So, effective anticancer therapies against OS should specifically target and destroy CSCs. We previously found that the let-7d microRNA was downregulated in the 3AB-OS-CSCs, derived from the human OS-MG63 cells. Here, we aimed to assess whether let-7d modulation affected tumorigenic and stemness properties of these OS-CSCs. We found that let-7d-overexpression reduced cell proliferation by decreasing CCND2 and E2F2 cell-cycle-activators and increasing p21 and p27 CDK-inhibitors. Let-7d also decreased sarcosphere-and-colony forming ability, two features associated with self-renewing, and it reduced the expression of stemness genes, including Oct3/4, Sox2, Nanog, Lin28B, and HMGA2. Moreover, let-7d induced mesenchymal-to-epithelial-transition, as shown by both N-Cadherin-E-cadherin-switch and decrease in vimentin. Surprisingly, such switch was accompanied by enhanced migratory/invasive capacities, with a strong increase in MMP9, CXCR4 and VersicanV1. Let-7d- overexpression also reduced cell sensitivity to apoptosis induced by both serum-starvation and various chemotherapy drugs, concomitant with decrease in caspase-3 and increase in BCL2 expression. Our data suggest that let-7d in 3AB-OS-CSCs could induce plastic-transitions from CSCs-to-non-CSCs and vice-versa. To our knowledge this is the first study to comprehensively examine the expression and functions of let-7d in OS-CSCs. By showing that let-7d has both tumor suppressor and oncogenic functions in this context, our findings suggest that, before prospecting new therapeutic strategies based on let-7d modulation, it is urgent to better define its multiple functions. J. Cell. Physiol. 231: 1832-1841, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Neoplasias Ósseas/metabolismo , MicroRNAs/metabolismo , Células-Tronco Neoplásicas/metabolismo , Osteossarcoma/metabolismo , Antineoplásicos/farmacologia , Apoptose , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Ciclo Celular , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Autorrenovação Celular , Resistencia a Medicamentos Antineoplásicos , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Invasividade Neoplásica , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/genética , Osteossarcoma/patologia , Fenótipo , Transdução de Sinais , Fatores de Tempo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção
17.
J Cell Physiol ; 230(6): 1276-89, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25370819

RESUMO

The sesquiterpene lactone Parthenolide (PN) exerted a cytotoxic effect on MDA-MB231 cells, a triple-negative breast cancer (TNBC) cell line, but its effectiveness was scarce when employed at low doses. This represents an obstacle for a therapeutic utilization of PN. In order to overcome this difficulty we associated to PN the suberoylanilide hydroxamic acid (SAHA), an histone deacetylase inhibitor. Our results show that SAHA synergistically sensitized MDA-MB231 cells to the cytotoxic effect of PN. It is noteworthy that treatment with PN alone stimulated the survival pathway Akt/mTOR and the consequent nuclear translocation of Nrf2, while treatment with SAHA alone induced autophagic activity. However, when the cells were treated with SAHA/PN combination, SAHA suppressed PN effect on Akt/mTOR/Nrf2 pathway, while PN reduced the prosurvival autophagic activity of SAHA. In addition SAHA/PN combination induced GSH depletion, fall in Δψm, release of cytochrome c, activation of caspase 3 and apoptosis. Finally we demonstrated that combined treatment maintained both hyperacetylation of histones H3 and H4 induced by SAHA and down-regulation of DNMT1 expression induced by PN. Inhibition of the DNA-binding activity of NF-kB, which is determined by PN, was also observed after combined treatment. In conclusion, combination of PN to SAHA inhibits the cytoprotective responses induced by the single compounds, but does not alter the mechanisms leading to the cytotoxic effects. Taken together our results suggest that this combination could be a candidate for TNBC therapy.


Assuntos
Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Sesquiterpenos/farmacologia , Autofagia/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Inibidores de Histona Desacetilases/metabolismo , Humanos , NF-kappa B/metabolismo , Vorinostat
18.
Int J Oncol ; 45(5): 2013-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25174983

RESUMO

Osteosarcoma (OS) is the most common type of bone cancer, with a peak incidence in the early childhood. Emerging evidence suggests that treatments targeting cancer stem cells (CSCs) within a tumor can halt cancer and improve patient survival. MicroRNAs (miRNAs) have been implicated in the maintenance of the CSC phenotype, thus, identification of CSC-related miRNAs would provide information for a better understanding of CSCs. Downregulation of miRNA-29 family members (miR-29a/b/c; miR­29s) was observed in human OS, however, little is known about the functions of miR-29s in human OS CSCs. Previously, during the characterization of 3AB-OS cells, a CSC line selected from human OS MG63 cells, we showed a potent downregulation of miR-29b. In this study, after stable transfection of 3AB-OS cells with miR-29b-1, we investigated the role of miR-29b-1 in regulating cell proliferation, sarcosphere-forming ability, clonogenic growth, chemosensitivity, migration and invasive ability of 3AB-OS cells, in vitro. We found that, miR-29b-1 overexpression consistently reduced both, 3AB-OS CSCs growth in two- and three-dimensional culture systems and their sarcosphere- and colony-forming ability. In addition, while miR-29b-1 overexpression sensitized 3AB-OS cells to chemotherapeutic drug-induced apoptosis, it did not influence their migratory and invasive capacities, thus suggesting a context-depending role of miR-29b-1. Using publicly available databases, we proceeded to identify potential miR-29b target genes, known to play a role in the above reported functions. Among these targets we analyzed CD133, N-Myc, CCND2, E2F1 and E2F2, Bcl-2 and IAP-2. We also analyzed the most important stemness markers as Oct3/4, Sox2 and Nanog. Real-time RT-PCR and western-blot analyses showed that miR-29b-1 negatively regulated the expression of these markers. Overall, the results show that miR-29b-1 suppresses stemness properties of 3AB-OS CSCs and suggest that developing miR-29b-1 as a novel therapeutic agent might offer benefits for OS treatment.


Assuntos
Neoplasias Ósseas/genética , Resistencia a Medicamentos Antineoplásicos/genética , MicroRNAs/biossíntese , Osteossarcoma/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Invasividade Neoplásica/genética , Osteossarcoma/patologia
19.
Oncol Rep ; 32(1): 167-72, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24859613

RESUMO

It has been shown that the sesquiterpene lactone parthenolide lowers the viability of MDA-MB-231 breast cancer cells, in correlation with oxidative stress. The present report examined the different radical species produced during parthenolide treatment and their possible role in the toxicity caused by the drug. Time course experiments showed that in the first phase of treatment (0-8 h), and in particular in the first 3 h, parthenolide induced dichlorofluorescein (DCF) signal in a large percentage of cells, while dihydroethidium (DHE) signal was not stimulated. Since the effect on DCF signal was suppressed by apocynin and diphenyleneiodonium (DPI), two inhibitors of NADPH oxidase (NOX), we suggest that parthenolide rapidly stimulated NOX activity with production of superoxide anion (O2•-), which was converted by superoxide dismutase 1 (SOD1) into hydrogen peroxide (H2O2). In the second phase of treatment (8-16 h), parthenolide increased the number of positive cells to DHE signal. Since this event was not prevented by apocynin and DPI and was associated with positivity of cells to MitoSox Red, a fluorochrome used to detect mitochondrial production of O2•-, we suggest that parthenolide induced production of O2•- at the mitochondrial level independently by NOX activity in the second phase of treatment. Finally, in this phase, most cells became positive to hydroxyphenyl fluorescein (HPF) signal, a fluorescent probe to detect highly reactive oxygen species (hROS), such as hydroxyl radical and peroxynitrite. Therefore, parthenolide between 8-16 h of treatment induced generation of O2•- and hROS, in close correlation with a marked reduction in cell viability.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Neoplasias da Mama/tratamento farmacológico , Peróxido de Hidrogênio/metabolismo , Sesquiterpenos/farmacologia , Superóxidos/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , NADPH Oxidases/metabolismo , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1
20.
Eur J Med Chem ; 72: 1-9, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24333609

RESUMO

The reaction under reflux between 1-phenyl-3-R-5-methylaminopyrazoles and 2,5-hexanedione lead to 5,7:7,13-dimethanopyrazolo[3,4-b]pyrazolo[3',4':2,3]azepino[4,5-f]azocine derivatives 3b-g. These unusual molecules show the structural complexity of many biologically active natural products and are endowed with the chemical diversity that is required in drug discovery. The compounds 3b,e were reduced by hydrogen in the presence of Palladium on activated charcoal to give the dihydro derivatives 5b,e. Compounds 3b-f and 5b,e were selected by the NCI to evaluate their in vitro antiproliferative activity against 60 human cell lines derived from nine clinically isolated cancer types (leukaemia, lung, colon, melanoma, renal, ovarian, brain, breast, and prostate). The most active compound of this series, caused a block in G0-G1 phase of cell cycle. Analysis of pRb expression showed that this compound favours pRb dephosphorylation.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Compostos Policíclicos/farmacologia , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HL-60 , Compostos Heterocíclicos de 4 ou mais Anéis/química , Humanos , Células K562 , Células MCF-7 , Modelos Moleculares , Estrutura Molecular , Compostos Policíclicos/síntese química , Compostos Policíclicos/química , Relação Estrutura-Atividade
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