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1.
Artigo em Inglês | MEDLINE | ID: mdl-34351104

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is a complex clinical syndrome that accounts for more than half of all heart failure patients. Identification, early diagnosis and management of patients are still complex, and no targeted treatment is available, since all tested drugs were not able to lower hard clinical outcomes. A multi-hormonal deficiency syndrome has been described in HFpEF patients suggesting that different hormones may represent new biomarkers of the disease, but their clinical utility is still debated. The natriuretic peptides are the cornerstone biomarker in heart failure, predicting cardiovascular death and heart failure hospitalization. Testosterone and DHEA-S deficiencies have been reported in HFpEF and associated with right ventricular impairment and diastolic dysfunction. IGFBP-1/IGF-1 axis correlates with echocardiographic parameters of HFpEF patients and with several prognostic biomarkers including NT-proBNP and C reactive protein. Low triiodothyronine syndrome is frequently found in HFpEF and thyroid hormones should represent a potential biomarker of risk stratification and prognosis.

2.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361060

RESUMO

Homeodomain-interacting protein kinase 2 (HIPK2) is a serine-threonine kinase that phosphorylates various transcriptional and chromatin regulators, thus modulating numerous important cellular processes, such as proliferation, apoptosis, DNA damage response, and oxidative stress. The role of HIPK2 in the pathogenesis of cancer and fibrosis is well established, and evidence of its involvement in the homeostasis of multiple organs has been recently emerging. We have previously demonstrated that Hipk2-null (Hipk2-KO) mice present cerebellar alterations associated with psychomotor abnormalities and that the double ablation of HIPK2 and its interactor HMGA1 causes perinatal death due to respiratory failure. To identify other alterations caused by the loss of HIPK2, we performed a systematic morphological analysis of Hipk2-KO mice. Post-mortem examinations and histological analysis revealed that Hipk2 ablation causes neuronal loss, neuronal morphological alterations, and satellitosis throughout the whole central nervous system (CNS); a myopathic phenotype characterized by variable fiber size, mitochondrial proliferation, sarcoplasmic inclusions, morphological alterations at neuromuscular junctions; and a cardiac phenotype characterized by fibrosis and cardiomyocyte hypertrophy. These data demonstrate the importance of HIPK2 in the physiology of skeletal and cardiac muscles and of different parts of the CNS, thus suggesting its potential relevance for different new aspects of human pathology.


Assuntos
Sistema Nervoso Central/patologia , Fibrose/patologia , Miocárdio/patologia , Neurônios/patologia , Proteínas Serina-Treonina Quinases/fisiologia , Animais , Sistema Nervoso Central/metabolismo , Feminino , Fibrose/metabolismo , Proteínas HMGA/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Neurônios/metabolismo , Fenótipo , Fosforilação
3.
Artigo em Inglês | MEDLINE | ID: mdl-34284526

RESUMO

Arterial stiffness, defined as the rigidity of the arterial wall, is the consequence of vascular aging and is associated with the full spectrum of cardiovascular diseases. Carotid-femoral pulse wave velocity (cf-PWV) is the gold standard method for arterial stiffness evaluation: it measures the velocity of the arterial pulse along the thoracic and abdominal aorta alongside arterial distensibility. Its value rises as stiffness progresses. Cf-PWV is helpful to assess residual cardiovascular risk (CVR) in hypertension (HT). In fact, an increase in pulsatility and arterial stiffness predicts CVR in patients affected by arterial HT, independently of other risk factors. Arterial stiffness can predict cardiovascular events in several other clinical conditions such as heart failure, diabetes, and pulmonary HT. However, cf-PWV has not been yet included in routine clinical practice so far. A possible reason might be its methodological and theoretical limitations (inaccuracy in the traveled distance, intra and interindividual variability, lack of well-defined references values, and age- and blood pressure-independent cutoff). To exceed these limits a strict adherence to guidelines, use of analytical approaches, and possibility of integrating the results with other stiffness examinations are essential approaches.

4.
Monaldi Arch Chest Dis ; 91(2)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33792231

RESUMO

Insulin resistance (IR) and the related hyperinsulinamia play a key role in the genesis and progression of the continuum of cardiovascular (CV) disease. Thus, it is reasonable to pursue in primary and secondary CV prevention, the pharmacological strategies that are capable to interfere with the development of IR. The renin-angiotensin-aldosterone system (RAAS) plays an important role in the pathogenesis of IR. In particular, angiotensin II (Ang II) through the generation of reactive oxygen species, induces a low grade of inflammation, which impairs the insulin signal transduction. The angiotensin converting enzyme (ACE) inhibitors are effective not only as blood pressure-lowering agents, but also as modulators of metabolic abnormalities. Indeed, experimental evidence indicates that in animal models of IR, ACE inhibitors are capable to ameliorate the insulin sensitivity. The Ang II receptor blockers (ARBs) modulate the peroxisome proliferator-activated receptor (PPAR)-γ activity. PPARâ€"γ is a transcription factor that controls the gene expression of several key enzymes of glucose metabolism. A further mechanism that accounts for the favorable metabolic properties of ARBs is the capability to modulate the hypothalamicâ€"pituitary-adrenal (HPA) axis. The available clinical evidence is consistent with the concept that both ACE inhibitors and ARBs are able to interfere with the development of IR and its consequences like type 2 diabetes. In addition, pharmacological inhibition of the RAAS has favourable effects on dyslipidaemias, metabolic syndrome and obesity. Therefore, the pharmacological antagonism of the RAAS, nowadays, represents the first choice in the prevention of cardio-metabolic diseases.

5.
Front Cell Infect Microbiol ; 11: 627043, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33718274

RESUMO

This study was aimed at analyzing proto-oncogenic signaling pathway activation in normal oral keratinocytes (NOK-si) and neoplastic cell lines (SCC 25 and Detroit 562) stimulated with metabolites (soluble factors) from single and dual biofilms of Candida albicans and Staphylococcus aureus. Soluble factors (SF) from early (16-h) and mature (36-h) biofilms of C. albicans and S. aureus were collected and incubated with cell cultures, which were subsequently evaluated using gene expression via RT-qPCR, cell viability via AlamarBlueTM, and flow cytometry cell cycle analysis. In general, exposure to the SF of early and mature biofilms from C. albicans and dual species caused a major reduction in NOK-si cell viability and enhanced the sub G0 phase. This led to a decrease in gene expression. However, in this cell line, SF of S. aureus biofilms upregulated the CDKN1A gene followed by the maintenance of cell viability and a significant increase in the G2/M population. For tumor cells, SCC 25 and Detroit 562, the stimuli of SF biofilms upregulated oncogenes such as hRAS and mTOR, as well as Bcl-2 and CDKN1A. SCC 25 and Detroit 562 cells could survive even after 24 h of stimuli from both SF (early and mature). This occurred without significant changes taking place in the cell cycle progression for SCC 25, and with a significant tendency to increase the G2/M phase for Detroit 562. These results point to the fact that metabolites from prevalent clinical fungal and bacterial biofilms, C. albicans and S. aureus, can disrupt the homeostasis of normal and neoplastic oral epithelial cells. This changes proto-oncogenes' expression, specifically PI3KCA, hRAS, mTOR, BRAF, and cell cycle genes CDKN1A and Bcl-2, thus causing a disturbance in cell viability, survival, and the cell cycle profile.


Assuntos
Candida albicans , Staphylococcus aureus , Biofilmes , Candida albicans/genética , Células Epiteliais , Genes cdc , Proto-Oncogenes , Staphylococcus aureus/genética
6.
Monaldi Arch Chest Dis ; 91(1)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33567818

RESUMO

The dysregulation of renin-angiotensin-system (RAS) plays a pivotal role in hypertension and in the development of the related target organ damage (TOD). The main goal of treating hypertension is represented by the long-term reduction of cardiovascular (CV) risk. RAS inhibition either by angiotensin converting enzyme (ACE)-inhibitors or by type 1 Angiotensin II receptors blockers (ARBs), reduce the incidence of CV events in hypertensive patients. Actually, ACE-inhibitors and ARBs have been demonstrated to be effective to prevent, or delay TOD like left ventricular hypertrophy, chronic kidney disease, and atherosclerosis. The beneficial effects of RAS blockers on clinical outcome of hypertensive patients are due to the key role of angiotensin II in the pathogenesis of TOD. In particular, Angiotensin II through an inflammatory-mediated mechanism plays a role in the initiation, progression and vulnerability of atherosclerotic plaque. In addition, Angiotensin II can be considered the hormonal transductor of the pressure overload in cardiac myocytes, and through an autocrine-paracrine mechanism plays a role in the development of left ventricular hypertrophy. Angiotensin II by modulating the redox status and the immune system participates to the development of chronic kidney disease. The RAS blocker should be considered the first therapeutic option in patients with hypertension, even if ACE-inhibitors and ARBs have different impact on CV prevention. ARBs seem to have greater neuro-protective effects, while ACE-inhibitors have greater cardio-protective action.

8.
Mol Med Rep ; 21(3): 1501-1508, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32016459

RESUMO

Colorectal cancer (CRC) is the third most prevalent type of cancer worldwide. It is also the second most common cause of cancer­associated mortality; it accounted for about 9.2% of all cancer deaths in 2018, most of which were due to resistance to therapy. The main treatment for CRC is surgery, generally associated with chemotherapy, radiation therapy and combination therapy. However, while chemo­radiotherapy kills differentiated cancer cells, mesenchymal stem­like cells are resistant to this treatment, and this can give rise to therapy­resistant tumors. Our previous study isolated T88 primary colon cancer cells from a patient with sporadic colon cancer. These cells exhibited mesenchymal and epithelial features, high levels of epithelial­to­mesenchymal transition transcription factors, and stemness markers. In addition, it was revealed that lithium chloride (LiCl), a specific glycogen synthase kinase (GSK)­3ß inhibitor, induced both the mesenchymal­to­epithelial transition and differentiation, and also reduced cell migration, stemness features and cell plasticity in these primary colon cancer cells. The aim of the present study was to investigate the effect of LiCl treatment on the viability of primary colon cancer cells exposed to 7 Gy delivered by high­energy photon beams, which corresponds to 6 megavolts of energy. To achieve this aim, the viability of irradiated T88 cells was compared with that of irradiated T88 cells pre­treated with LiCl. As expected, it was observed that LiCl sensitized primary colon cancer cells to high­energy photon irradiation treatment. Notably, the decrease in cell viability was greater with combined therapy than with irradiation alone. To explore the molecular basis of this response, the effect of LiCl on the expression of Bax, p53 and Survivin, which are proteins involved in the apoptotic mechanism and in death escape, was analyzed. The present study revealed that LiCl upregulated the expression of pro­apoptotic proteins and downregulated the expression of proteins involved in survival. These effects were enhanced by high­energy photon irradiation, suggesting that LiCl could be used to sensitize colon cancer cells to radiation therapy.


Assuntos
Cloreto de Lítio/farmacologia , Fótons , Tolerância a Radiação/efeitos dos fármacos , Radiossensibilizantes/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/radioterapia , Humanos , Radioterapia de Alta Energia/métodos , Transdução de Sinais/efeitos dos fármacos
9.
Cancer Gene Ther ; 27(5): 319-329, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31138900

RESUMO

The Holliday Junction-Recognition Protein (HJURP) was reported as overexpressed in several cancers and also strongly correlated with poor prognosis of patients, especially in glioblastoma (GBM), the most common and deadly type of primary brain tumor. HJURP is responsible for loading the histone H3 variant-the Centromeric Protein A (CENP-A)-at the centromeres in a cell cycle-regulated manner, being required for proper chromosome segregation. Here we investigated HJURP association with survival and radioresistance of different GBM cell lines. HJURP knockdown compromised the clonogenic capacity and severely impaired survival of five distinct GBM cells, while nontumor astrocytes were not affected. U251MG cells showed a robust cell cycle arrest in G2/M phases followed by a drastic increment in cell death after HJURP silencing, while U138MG and U343MG cell lines presented augmented senescence with a comparable increase in cell death. Importantly, we verified that the impact on cell cycle dynamics and clonogenic survival were associated with loss CENP-A at the centromeres. Moreover, radiation resistance was also impacted by HJURP modulation in several GBM cell lines. U87MG, T98G, U138MG, and U343MG cells were all sensitized to ionizing radiation after HJURP reduction. These data reinforce the requirement of HJURP for proliferative capacity and radioresistance of tumor cells, underlining its potential as a promising therapeutic target for GBM.


Assuntos
Neoplasias Encefálicas/radioterapia , Proteína Centromérica A/metabolismo , Proteínas de Ligação a DNA/metabolismo , Glioblastoma/radioterapia , Células-Tronco Neoplásicas/efeitos da radiação , Neoplasias Encefálicas/patologia , Pontos de Checagem do Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Centrômero/metabolismo , Centrômero/efeitos da radiação , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Glioblastoma/patologia , Humanos , Células-Tronco Neoplásicas/patologia , Tolerância a Radiação/genética , Ensaio Tumoral de Célula-Tronco
10.
Cell Death Dis ; 10(10): 747, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582725

RESUMO

The serine-threonine kinase homeodomain-interacting protein kinase 2 (HIPK2) modulates important cellular functions during development, acting as a signal integrator of a wide variety of stress signals, and as a regulator of transcription factors and cofactors. We have previously demonstrated that HIPK2 binds and phosphorylates High-Mobility Group A1 (HMGA1), an architectural chromatinic protein ubiquitously expressed in embryonic tissues, decreasing its binding affinity to DNA. To better define the functional role of HIPK2 and HMGA1 interaction in vivo, we generated mice in which both genes are disrupted. About 50% of these Hmga1/Hipk2 double knock-out (DKO) mice die within 12 h of life (P1) for respiratory failure. The DKO mice present an altered lung morphology, likely owing to a drastic reduction in the expression of surfactant proteins, that are required for lung development. Consistently, we report that both HMGA1 and HIPK2 proteins positively regulate the transcriptional activity of the genes encoding the surfactant proteins. Moreover, these mice display an altered expression of thyroid differentiation markers, reasonably because of a drastic reduction in the expression of the thyroid-specific transcription factors PAX8 and FOXE1, which we demonstrate here to be positively regulated by HMGA1 and HIPK2. Therefore, these data indicate a critical role of HIPK2/HMGA1 cooperation in lung and thyroid development and function, suggesting the potential involvement of their impairment in the pathogenesis of human lung and thyroid diseases.


Assuntos
Proteína HMGA1a/genética , Proteínas Serina-Treonina Quinases/genética , Doenças Respiratórias/genética , Glândula Tireoide/anormalidades , Animais , Animais Recém-Nascidos , Desenvolvimento Embrionário , Deleção de Genes , Regulação da Expressão Gênica , Proteína HMGA1a/metabolismo , Células HeLa , Humanos , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Associadas a Surfactantes Pulmonares , Doenças Respiratórias/patologia , Glândula Tireoide/embriologia , Glândula Tireoide/patologia
11.
Eur J Hum Genet ; 27(10): 1509-1518, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31231133

RESUMO

Incontinentia pigmenti (IP; OMIM#308300) is a rare genetic disease resulting in neuroectodermal defects, which can lead to disability. At present, there is neither definitive cure available nor are there any sufficiently reliable insights to predict the severity of the disease. We launched the Incontinentia Pigmenti Genetic Biobank (IPGB) project ( http://www.igb.cnr.it/ipgb ) in 2015 to establish a large-scale deposit of biological samples, to provide detailed clinical information about children diagnosed with IP and to facilitate research. We have built a cohort comprising samples of 381 clinically confirmed patients with IP and 633 healthy individuals recruited through IP patients' associations. The collection includes 269 trios, 83 duos, and 95 families with at least two affected members and represents an extensive dataset (200 cooperative medical institutes, 139 in Italy and 61 worldwide) that enables a comprehensive phenotyping. Joining the IPGB guarantees all participants access to the results including the genetic testing of IP and the long-term storage of the samples. The IPGB is the largest IP sample collection and one of the largest rare-disease-oriented collections in the world and will be open to requests for access to data by the national and international scientific community.


Assuntos
Bancos de Espécimes Biológicos , Incontinência Pigmentar/genética , Doenças Raras , Bases de Dados Genéticas , Feminino , Geografia Médica , Saúde Global , Humanos , Incontinência Pigmentar/diagnóstico , Incontinência Pigmentar/epidemiologia , Masculino , Linhagem , Sistema de Registros , Pesquisa , Projetos de Pesquisa , Fatores Socioeconômicos , Navegador
12.
Pharmacogenomics J ; 19(1): 72-82, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30131588

RESUMO

Multiple Sclerosis (MS) is an inflammatory neurodegenerative disease that affects approximately 2.5 million people globally. Even though the etiology of MS remains unknown, it is accepted that it involves a combination of genetic alterations and environmental factors. Here, after performing whole exome sequencing, we found a MS patient harboring a rare and homozygous single nucleotide variant (SNV; rs61745847) of the G-protein coupled receptor (GPCR) galanin-receptor 2 (GALR2) that alters an important amino acid in the TM6 molecular toggle switch region (W249L). Nuclear magnetic resonance imaging showed that the hypothalamus (an area rich in GALR2) of this patient exhibited an important volumetric reduction leading to an enlarged third ventricle. Ex vivo experiments with patient-derived blood cells (AKT phosphorylation), as well as studies in recombinant cell lines expressing the human GALR2 (calcium mobilization and NFAT mediated gene transcription), showed that galanin (GAL) was unable to stimulate cell signaling in cells expressing the variant GALR2 allele. Live cell confocal microscopy showed that the GALR2 mutant receptor was primarily localized to intracellular endosomes. We conclude that the W249L SNV is likely to abrogate GAL-mediated signaling through GALR2 due to the spontaneous internalization of this receptor in this patient. Although this homozygous SNV was rare in our MS cohort (1:262 cases), our findings raise the potential importance of impaired neuroregenerative pathways in the pathogenesis of MS, warrant future studies into the relevance of the GAL/GALR2 axis in MS and further suggest the activation of GALR2 as a potential therapeutic route for this disease.


Assuntos
Galanina/genética , Esclerose Múltipla/genética , Receptor Tipo 2 de Galanina/genética , Adulto , Sequência de Aminoácidos , Sequência de Bases , Estudos de Casos e Controles , Linhagem Celular , Feminino , Células HEK293 , Humanos , Fosforilação/genética , Polimorfismo de Nucleotídeo Único/genética , Transdução de Sinais/genética , Adulto Jovem
13.
Pigment Cell Melanoma Res ; 32(2): 303-314, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30457212

RESUMO

RMEL3 is a recently identified lncRNA associated with BRAFV600E mutation and melanoma cell survival. Here, we demonstrate strong and moderate RMEL3 upregulation in BRAF and NRAS mutant melanoma cells, respectively, compared to melanocytes. High expression is also more frequent in cutaneous than in acral/mucosal melanomas, and analysis of an ICGC melanoma dataset showed that mutations in RMEL3 locus are preponderantly C > T substitutions at dipyrimidine sites including CC > TT, typical of UV signature. RMEL3 mutation does not correlate with RMEL3 levels, but does with poor patient survival, in TCGA melanoma dataset. Accordingly, RMEL3 lncRNA levels were significantly reduced in BRAFV600E melanoma cells upon treatment with BRAF or MEK inhibitors, supporting the notion that BRAF-MEK-ERK pathway plays a role to activate RMEL3 gene transcription. RMEL3 overexpression, in immortalized fibroblasts and melanoma cells, increased proliferation and survival under serum starvation, clonogenic ability, and xenografted melanoma tumor growth. Although future studies will be needed to elucidate the mechanistic activities of RMEL3, our data demonstrate that its overexpression bypasses the need of mitogen activation to sustain proliferation/survival of non-transformed cells and suggest an oncogenic role for RMEL3.


Assuntos
Citoproteção , Melanoma/genética , Melanoma/patologia , RNA Longo não Codificante/metabolismo , Soro/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Transformada , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Clonais , Citoproteção/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/patologia , GTP Fosfo-Hidrolases/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Células NIH 3T3 , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , RNA Longo não Codificante/genética
14.
Eur J Med Chem ; 164: 8-26, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30583248

RESUMO

Glioblastoma (GBM) is one of the most common central nervous system cancers. It is characterized as a fast-growing tumor that arises from multiple cell types with neural stem-cell-like properties. Additionally, GBM tumors are highly invasive, which is attributed to the presence of glioblastoma stem cells that makes surgery ineffective in most cases. Currently, temozolomide is the unique chemotherapy option approved by the U.S. Food and Drug Administration for GBM treatment. This review analyzes the emergence and development of new synthetic small molecules discovered as promising anti-glioblastoma agents. A number of compounds were described herein and grouped according to the main chemical class used in the drug discovery process. Importantly, we focused only on synthetic compounds published in the last 10 years, thus excluding natural products. Furthermore, we included in this review only those most biologically active compounds with proven in vitro and/or in vivo efficacy.


Assuntos
Glioblastoma/tratamento farmacológico , Animais , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Descoberta de Drogas , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia
15.
Genet Mol Biol ; 43(1 suppl 1): e20190066, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31930277

RESUMO

Glioblastoma (GBM) is the most common and malignant type of primary brain tumor, showing rapid development and resistance to therapies. On average, patients survive 14.6 months after diagnosis and less than 5% survive five years or more. Several pieces of evidence have suggested that the DNA damage signaling and repair activities are directly correlated with GBM phenotype and exhibit opposite functions in cancer establishment and progression. The functions of these pathways appear to present a dual role in tumorigenesis and cancer progression. Activation and/or overexpression of ATRX, ATM and RAD51 genes were extensively characterized as barriers for GBM initiation, but paradoxically the exacerbated activity of these genes was further associated with cancer progression to more aggressive stages. Excessive amounts of other DNA repair proteins, namely HJURP, EXO1, NEIL3, BRCA2, and BRIP, have also been connected to proliferative competence, resistance and poor prognosis. This scenario suggests that these networks help tumor cells to manage replicative stress and treatment-induced damage, diminishing genome instability and conferring therapy resistance. Finally, in this review we address promising new drugs and therapeutic approaches with potential to improve patient survival. However, despite all technological advances, the prognosis is still dismal and further research is needed to dissect such complex mechanisms.

16.
Phytomedicine ; 48: 179-186, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-30195876

RESUMO

BACKGROUND: Cervical cancer, the fourth most common type of cancer among women worldwide, accounts for approximately 12% of all types of malignancies that affect women. Natural products have contributed significantly to the development of modern therapies; approximately 70% of the drugs available for chemotherapy are naturally based products. PURPOSE: The purpose of this study was to examine the biological activities of nitensidine B (NTB), a guanidinic alkaloid isolated from the leaves of Pterogyne nitens Tul. (Fabaceae) in a cervical cancer cell line. METHODS: In vitro experiments were performed using cervical carcinoma cells immortalized by human papillomavirus type 16 (HPV16, SiHa cells), since epidemiological and molecular studies have demonstrated robust associations between the etiologies of cervical cancer and HPV infection. Cytotoxicity as well as the effect of NTB treatment on intracellular signals of apoptosis, fragmentation of internucleosomal DNA via terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and levels of apoptosis effectors (Caspase 3/7) were evaluated. In addition, differential proteomic analysis (iTRAQ) and protein validation using western blot were performed. RESULTS: The cytotoxicity of NTB treatment in the SiHa cell line was concentration-dependent, with the minimum inhibitory concentration of 50% of the cells of 40.98 µM. In the TUNEL assay, SiHa cell apoptosis with 3/7 caspase activation was reported at 12 h following treatment. Differential proteomic analysis by iTRAQ demonstrated that proteins of the glycolytic pathway, aldolase A, alpha-enolase, pyruvate kinase, and glyceraldehyde 3-phosphate dehydrogenase were underexpressed. CONCLUSION: These results indicated that NTB could play a role in decreasing glycolysis . Since tumor cells prefer the glycolytic pathway to generate energy, these findings suggest that NTB may be a reliable model for the study of human cervical cancer cell lines immortalized by HPV16, however more experiments can be performed.


Assuntos
Apoptose/efeitos dos fármacos , Glicólise , Guanidinas/farmacologia , Papillomavirus Humano 16 , Neoplasias do Colo do Útero/virologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Fabaceae/química , Feminino , Humanos , Folhas de Planta/química , Proteoma
17.
Tumour Biol ; 39(4): 1010428317694552, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28378638

RESUMO

Astrocytomas are the most common primary brain tumors. They are very resistant to therapies and usually progress rapidly to high-grade lesions. Here, we investigated the potential role of DNA repair genes in astrocytoma progression and resistance. To this aim, we performed a polymerase chain reaction array-based analysis focused on DNA repair genes and searched for correlations between expression patters and survival prognoses. We found 19 genes significantly altered. Combining these genes in all possible arrangements, we found 421 expression signatures strongly associated with poor survival. Importantly, five genes (DDB2, EXO1, NEIL3, BRCA2, and BRIP1) were independently correlated with worse prognoses, revealing single-gene signatures. Moreover, silencing of EXO1, which is remarkably overexpressed, promoted faster restoration of double-strand breaks, while NEIL3 knockdown, also highly overexpressed, caused an increment in DNA damage and cell death after irradiation of glioblastoma cells. These results disclose the importance of DNA repair pathways for the maintenance of genomic stability of high-grade astrocytomas and suggest that EXO1 and NEIL3 overexpression confers more efficiency for double-strand break repair and resistance to reactive oxygen species, respectively. Thereby, we highlight these two genes as potentially related with tumor aggressiveness and promising candidates as novel therapeutic targets.


Assuntos
Astrocitoma/mortalidade , Neoplasias Encefálicas/mortalidade , Reparo do DNA , Apoptose , Astrocitoma/genética , Astrocitoma/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Enzimas Reparadoras do DNA/genética , Enzimas Reparadoras do DNA/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , N-Glicosil Hidrolases/genética , N-Glicosil Hidrolases/metabolismo , Prognóstico
18.
Oncotarget ; 8(15): 24518-24532, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28445939

RESUMO

Radiation therapy is widely used to treat human malignancies, but many tumor types, including gliomas, exhibit significant radioresistance. Radiation therapy creates DNA double-strand breaks (DSBs), and DSB repair is linked to rapid changes in epigenetic modifications, including increased histone methylation. This increased histone methylation recruits DNA repair proteins which can then alter the local chromatin structure and promote repair. Consequently, combining inhibitors of specific histone methyltransferases with radiation therapy may increase tumor radiosensitivity, particularly in tumors with significant therapeutic resistance. Here, we demonstrate that inhibitors of the H4K20 methyltransferase SETD8 (UNC-0379) and the H3K9 methyltransferase G9a (BIX-01294) are effective radiosensitizers of human glioma cells. UNC-0379 blocked H4K20 methylation and reduced recruitment of the 53BP1 protein to DSBs, although this loss of 53BP1 caused only limited changes in radiosensitivity. In contrast, loss of H3K9 methylation through G9a inhibition with BIX-01294 increased radiosensitivity of a panel of glioma cells (SER2Gy range: 1.5 - 2.9). Further, loss of H3K9 methylation reduced DSB signaling dependent on H3K9, including reduced activation of the Tip60 acetyltransferase, loss of ATM signaling and reduced phosphorylation of the KAP-1 repressor. In addition, BIX-0194 inhibited DSB repair through both the homologous recombination and nonhomologous end-joining pathways. Inhibition of G9a and loss of H3K9 methylation is therefore an effective approach for increasing radiosensitivity of glioma cells. These results suggest that combining inhibitors of histone methyltransferases which are critical for DSB repair with radiation therapy may provide a new therapeutic route for sensitizing gliomas and other tumors to radiation therapy.


Assuntos
Dano ao DNA/genética , Glioma/genética , Histonas/metabolismo , Glioma/metabolismo , Glioma/patologia , Humanos , Metilação , Radiossensibilizantes , Transdução de Sinais
19.
BMC Cancer ; 17(1): 123, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28187758

RESUMO

BACKGROUND: Photodynamic therapy (PDT) has proven to be a promising alternative to current cancer treatments, especially if combined with conventional approaches. The technique is based on the administration of a non-toxic photosensitizing agent to the patient with subsequent localized exposure to a light source of a specific wavelength, resulting in a cytotoxic response to oxidative damage. The present study intended to evaluate in vitro the type of induced death and the genotoxic and mutagenic effects of PDT alone and associated with cisplatin. METHODS: We used the cell lines SiHa (ATCC® HTB35™), C-33 A (ATCC® HTB31™) and HaCaT cells, all available at Dr. Christiane Soares' Lab. Photosensitizers were Photogem (PGPDT) and methylene blue (MBPDT), alone or combined with cisplatin. Cell death was accessed through Hoechst and Propidium iodide staining and caspase-3 activity. Genotoxicity and mutagenicity were accessed via flow cytometry with anti-gama-H2AX and micronuclei assay, respectively. Data were analyzed by one-way ANOVA with Tukey's posthoc test. RESULTS: Both MBPDT and PGPDT induced caspase-independent death, but MBPDT induced the morphology of typical necrosis, while PGPDT induced morphological alterations most similar to apoptosis. Cisplatin predominantly induced apoptosis, and the combined therapy induced variable rates of apoptosis- or necrosis-like phenotypes according to the cell line, but the percentage of dead cells was always higher than with monotherapies. MBPDT, either as monotherapy or in combination with cisplatin, was the unique therapy to induce significant damage to DNA (double strand breaks) in the three cell lines evaluated. However, there was no mutagenic potential observed for the damage induced by MBPDT, since the few cells that survived the treatment have lost their clonogenic capacity. CONCLUSIONS: Our results elicit the potential of combined therapy in diminishing the toxicity of antineoplastic drugs. Ultimately, photodynamic therapy mediated by either methylene blue or Photogem as monotherapy or in combination with cisplatin has low mutagenic potential, which supports its safe use in clinical practice for the treatment of cervical cancer.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Cisplatino/farmacologia , Luz , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Histonas/metabolismo , Humanos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Fotoquimioterapia/métodos , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
20.
FEBS Open Bio ; 6(11): 1040-1053, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27833845

RESUMO

Different isoforms of ataxin-2 are predicted in Drosophila and may underlie different cellular processes. Here, we validated the isoforms B and C of Drosophila ataxin-2 locus (dAtx2), which we found to be expressed in various tissues and at different levels during development. dAtx2-B mRNA was detected at low amounts during all developmental stages, whereas dAtx2-C mRNA levels increase by eightfold from L3 to pupal-adult stages. Higher amounts of dAtx2-B protein were detected in embryos, while dAtx2-C protein was also expressed in higher levels in pupal-adult stages, indicating post-transcriptional control for isoform B and transcription induction for isoform C, respectively. Moreover, in the fat body of L3 larvae dAtx2-C, but not dAtx2-B, accumulates in cytoplasmic foci that colocalize with sec23, a marker of endoplasmic reticulum exit sites (ERES). Interestingly, animals subjected to selective knockdown of dAtx2 in the larval fat body do not complete metamorphosis and die at the third larval stage or early puparium. Additionally, larvae knocked down for dAtx2, grown at 29 °C, are significantly smaller than control animals due to reduction in DNA replication and cell growth, which are consistent with the decreased levels of phosphorylated-AKT observed in the fat body. Based on the localization of ataxin-2 (dAtx2-C) in ERESs, and on the phenotypes observed by dAtx2 knockdown in the larval fat body, we speculate a possible role for this protein in processes that regulate ERES formation. These data provide new insights into the biological function of ataxin-2 with potential relevance to neurodegenerative diseases.

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