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1.
J Clin Invest ; 134(15)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38885332

RESUMO

Most children with medulloblastoma (MB) achieve remission, but some face very aggressive metastatic tumors. Their dismal outcome highlights the critical need to advance therapeutic approaches that benefit such high-risk patients. Minnelide, a clinically relevant analog of the natural product triptolide, has oncostatic activity in both preclinical and early clinical settings. Despite its efficacy and tolerable toxicity, this compound has not been evaluated in MB. Utilizing a bioinformatic data set that integrates cellular drug response data with gene expression, we predicted that Group 3 (G3) MB, which has a poor 5-year survival, would be sensitive to triptolide/Minnelide. We subsequently showed that both triptolide and Minnelide attenuate the viability of G3 MB cells ex vivo. Transcriptomic analyses identified MYC signaling, a pathologically relevant driver of G3 MB, as a downstream target of this class of drugs. We validated this MYC dependency in G3 MB cells and showed that triptolide exerts its efficacy by reducing both MYC transcription and MYC protein stability. Importantly, Minnelide acted on MYC to reduce tumor growth and leptomeningeal spread, which resulted in improved survival of G3 MB animal models. Moreover, Minnelide improved the efficacy of adjuvant chemotherapy, further highlighting its potential for the treatment of MYC-driven G3 MB.


Assuntos
Diterpenos , Compostos de Epóxi , Meduloblastoma , Fenantrenos , Proteínas Proto-Oncogênicas c-myc , Ensaios Antitumorais Modelo de Xenoenxerto , Fenantrenos/farmacologia , Diterpenos/farmacologia , Compostos de Epóxi/farmacologia , Meduloblastoma/tratamento farmacológico , Meduloblastoma/genética , Meduloblastoma/patologia , Meduloblastoma/metabolismo , Animais , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Linhagem Celular Tumoral , Pró-Fármacos/farmacologia , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Organofosfatos
2.
Hematol Oncol ; 42(3): e3281, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38775115

RESUMO

The FLT3-ITD mutation represents the most frequent genetic alteration in newly diagnosed acute myeloid leukemia (AML) patient and is associated with poor prognosis. Mutation result in the retention of a constitutively active form of this receptor in the endoplasmic reticulum (ER) and the subsequent modification of its downstream effectors. Here, we assessed the impact of such retention on ER homeostasis and found that mutant cells present lower levels of ER stress due to the overexpression of ERO1α, one of the main proteins of the protein folding machinery at the ER. Overexpression of ERO1α resulted essential for ITD mutant cells survival and chemoresistance and also played a crucial role in shaping the type of glucose metabolism in AML cells, being the mitochondrial pathway the predominant one in those with a higher ER stress (non-mutated cells) and the glycolytic pathway the predominant one in those with lower ER stress (mutated cells). Our data indicate that FLT3 mutational status dictates the route for glucose metabolism in an ERO1α depending on manner and this provides a survival advantage to tumors carrying these ITD mutations.


Assuntos
Estresse do Retículo Endoplasmático , Retículo Endoplasmático , Leucemia Mieloide Aguda , Tirosina Quinase 3 Semelhante a fms , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , Retículo Endoplasmático/metabolismo , Mutação , Linhagem Celular Tumoral , Glicoproteínas de Membrana , Oxirredutases
3.
Foods ; 13(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38611418

RESUMO

Coffee fruit cascara, which is the skin and pulp of the coffee cherry, has been authorized as a novel food for commercialization in the European Union. The present research assessed the feasibility of using spray drying to produce a soluble powder called instant cascara (IC), employing sun-dried ripe coffee cherry pulp as a raw material. Although there were no significant differences (p > 0.05) in the overall antioxidant capacity between the freeze-dried and spray-dried samples, after an in vitro simulation of the digestion process, the spray-dried sample was significantly (p < 0.05) more antioxidant. Both samples reduced physiological intracellular ROS and significantly decreased (p < 0.05) the secretion of the pro-inflammatory factor NO. Alkaloids and phenolic compounds were detected in intestinal digests. In conclusion, spray drying is a good technique for producing IC as its use does not affect its properties and causes less environmental impact than freeze drying, as calculated by life cycle assessment. Sensory analysis did not show significant differences between the commercial beverage and the IC beverage in the adult population. IC at 10 mg/mL was significantly less accepted in adolescents than the commercial beverage. Future work will include the reformulation of the IC beverage at 10 mg/mL, which has antioxidant and anti-inflammatory potential, to increase its hedonic acceptance in all consumer segments.

4.
Cell Oncol (Dordr) ; 47(3): 1065-1070, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38150153

RESUMO

STAT3 is a pleiotropic transcription factor overactivated in 70% of solid tumours. We have recently reported that inactivating mutations on residues susceptible to post-translational modifications (PTMs) in only one of the monomers (i.e. asymmetric) caused changes in the cellular distribution of STAT3 homodimers. Here, we used more controlled experimental conditions, i.e. without the interference of endogenous STAT3 (STAT3-/- HeLa cells) and in the presence of a defined cytokine stimulus (Leukemia Inhibitory Factor, LIF), to provide further evidence that asymmetric PTMs affect the nuclear translocation of STAT3 homodimers. Time-lapse microscopy for 20 min after LIF stimulation showed that S727 dephosphorylation (S727A) and K685 inactivation (K685R) slightly enhanced the nuclear translocation of STAT3 homodimers, while K49 inactivation (K49R) delayed STAT3 nuclear translocation. Our findings suggest that asymmetrically modified STAT3 homodimers could be a new level of STAT3 regulation and, therefore, a potential target for cancer therapy.


Assuntos
Núcleo Celular , Fator Inibidor de Leucemia , Multimerização Proteica , Processamento de Proteína Pós-Traducional , Fator de Transcrição STAT3 , Humanos , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Células HeLa , Fator Inibidor de Leucemia/metabolismo , Fosforilação , Transporte Proteico/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo
5.
Chemistry ; 29(40): e202301078, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37103792

RESUMO

Platinum(II) complexes bearing N-heterocyclic carbenes based guanosine and caffeine have been synthesized by unassisted C-H oxidative addition, leading to the corresponding trans-hydride complexes. Platinum guanosine derivatives bearing triflate as counterion or bromide instead of hydride as co-ligand were also synthesized to facilitate correlation between structure and activity. The hydride compounds show high antiproliferative activity against all cell lines (TC-71, MV-4-11, U-937 and A-172). Methyl Guanosine complex 3, bearing a hydride ligand, is up to 30 times more active than compound 4, with a bromide in the same position. Changing the counterion has no significant effect in antiproliferative activity. Increasing bulkiness at N7, with an isopropyl group (compound 6), allows to maintain the antiproliferative activity while decreasing toxicity for non-cancer cells. Compound 6 leads to an increase in endoplasmic reticulum and autophagy markers on TC71 and MV-4-11 cancer cells, induces reductive stress and increases glutathione levels in cancer cells but not in non-cancer cell line HEK-293.


Assuntos
Antineoplásicos , Platina , Humanos , Platina/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Ligantes , Brometos , Células HEK293 , Guanosina , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais
6.
Antioxidants (Basel) ; 12(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36978864

RESUMO

Most effective anticancer drugs normally generate considerable cytotoxicity in normal cells; therefore, the preferential activation of apoptosis in cancer cells and the reduction of toxicity in normal cells is a great challenge in cancer research. Natural products with selective anticancer properties used as complementary medicine can help to achieve this goal. The aim of the present study was to analyze the effect of the addition of bee products [propolis (PR) or royal jelly (RJ) or propolis and royal jelly (PR+RJ), 2-10%] to thyme (TH) and chestnut honeys (CH) on the differential anticancer properties, mainly the cytotoxic and pro-apoptotic effects, in normal and cancer hepatic cells. The cytotoxic effects of samples were analyzed using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay (0-250 mg/mL) and the effects on apoptosis were analyzed using cell cycle analysis, TdT-dUTP terminal nick-end labeling (TUNEL) assay, DR5 (Death Receptor 5) and BAX (BCL-2-Associated X) activation, and caspases 8, 9, and 3 activities. Both honey samples alone and honey mixtures had no or very little apoptotic effect on normal cells. Antioxidant honey mixtures enhanced the apoptotic capacity of the corresponding honey alone via both extrinsic and intrinsic pathways. Of all the samples, chestnut honey enriched with 10% royal jelly and 10% propolis (sample 14, CH+10RJ+10PR) showed the highest apoptotic effect on tumor liver cells. The enrichment of monofloral honey with bee products could be used together with conventional anticancer treatments as a dietary supplement without side effects. On the other hand, it could be included in the diet as a natural sweetener with high added value.

7.
Lancet Neurol ; 22(2): 137-146, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36681446

RESUMO

BACKGROUND: Pilot clinical trials have shown the safety of intra-arterial bone marrow mononuclear cells (BMMNCs) in stroke. However, the efficacy of different doses of intra-arterial BMMNCs in patients with acute stroke has not been tested in a randomised clinical trial. We aimed to show safety and efficacy of two different doses of autologous intra-arterial BMMNC transplantation in patients with acute stroke. METHODS: The IBIS trial was a multicentre phase 2, randomised, controlled, investigator-initiated, assessor-blinded, clinical trial, in four stroke centres in Spain. We included patients (aged 18-80 years) with a non-lacunar, middle cerebral artery ischaemic stroke within 1-7 days from stroke onset and with a National Institutes of Health Stroke Scale score of 6-20. We randomly assigned patients (2:1:1) with a computer-generated randomisation sequence to standard of care (control group) or intra-arterial injection of autologous BMMNCs at one of two different doses (2 × 106 BMMNCs/kg or 5 × 106 BMMNCs/kg). The primary efficacy outcome was the proportion of patients with modified Rankin Scale scores of 0-2 at 180 days in the intention-to-treat population, comparing each BMMNC dose group and the pooled BMMNC group versus the control group. The primary safety endpoint was the proportion of serious adverse events. This trial was registered at ClinicalTrials.gov, NCT02178657 and is completed. FINDINGS: Between April 1, 2015, and May 20, 2021, we assessed 114 patients for eligibility. We randomly assigned 77 (68%) patients: 38 (49%) to the control group, 20 (26%) to the low-dose BMMNC group, and 19 (25%) the high-dose BMMNC group. The mean age of participants was 62·4 years (SD 12·7), 46 (60%) were men, 31 (40%) were women, all were White, and 63 (82%) received thrombectomy. The median NIHSS score before randomisation was 12 (IQR 9-15), with intra-arterial BMMNC injection done a median of 6 days (4-7) after stroke onset. The primary efficacy outcome occurred in 14 (39%) patients in the control group versus ten (50%) in the low-dose group (adjusted odds ratio 2·08 [95% CI 0·55-7·85]; p=0·28), eight (44%) in the high-dose group (1·89 [0·52-6·96]; p=0·33), and 18 (47%) in the pooled BMMNC group (2·22 [0·72-6·85]; p=0·16). We found no differences in the proportion of patients who had adverse events or dose-related events, but two patients had a groin haematoma after cell injection in the low-dose BMMNC group. INTERPRETATION: Intra-arterial BMMNCs were safe in patients with acute ischaemic stroke, but we found no significant improvement at 180 days on the mRS. Further clinical trials are warranted to investigate whether improvements might be possible at different timepoints. FUNDING: Instituto de Salud Carlos III co-funded by the European Regional Development Fund/European Social Fund, Mutua Madrileña, and the Regional Ministry of Health of Andalusia.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Espanha , Medula Óssea , Resultado do Tratamento , Transplante de Células
8.
Artigo em Inglês | MEDLINE | ID: mdl-36554850

RESUMO

The aim of the present study was to validate the cytotoxicity, genotoxicity, and preventive potential against benzo(a)pyrene (BaP)-induced DNA damage of nine samples of thyme and chestnut honeys enriched with bee products (royal jelly and propolis, 2-10%). Cell viability was determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay (0-250 mg/mL) to select nontoxic concentrations, and DNA damage (0.1-10 µg/mL) was evaluated by the alkaline single-cell gel electrophoresis or comet assay. Treatment with honey samples or royal jelly and propolis did not affect the viability of HepG2 cells up to 100 and 50 mg/mL, respectively. Treatment with 100 µM BaP significantly increased (p ≤ 0.001) the levels of the DNA strand breaks. None of the tested concentrations (0.1-10 µg/mL) of the honey samples (thyme and chestnut), royal jelly, and propolis caused DNA damage per se. All tested samples at all the concentrations used decreased the genotoxic effect of BaP. In addition, all mixtures of thyme or chestnut honeys with royal jelly or propolis showed a greater protective effect against BaP than the samples alone, being the thyme and chestnut honey samples enriched with 10% royal jelly and 10% propolis the most effective (70.4% and 69.4%, respectively). The observed protective effect may be associated with the phenolic content and antioxidant capacity of the studied samples. In conclusion, the thyme and chestnut honey samples enriched with bee products present potential as natural chemoprotective agents against the chemical carcinogen BaP.


Assuntos
Mel , Própole , Thymus (Planta) , Mel/análise , Benzo(a)pireno/toxicidade , Própole/farmacologia , Dano ao DNA
9.
Foods ; 11(19)2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36230193

RESUMO

Honey consumption and imports have increased in recent years, and it is considered by consumers to be a healthy alternative to more commonly used sweeteners. Honey contains a mixture of polyphenols and antioxidant compounds, and the botanical origin and geographical area of collection play an important role on its chemical composition. The present study investigated the physicochemical properties, total phenolic content and antioxidant capacity of Spanish thyme honey and chestnut honey, and their mixtures with royal jelly (2% and 10%) and propolis (2% and 10%). The analysis of the physicochemical parameters of both honey samples showed values within the established limits. Propolis showed the highest value of total phenolic content (17.21-266.83 mg GAE/100 g) and antioxidant capacity (DPPH, ORAC and ABTS assays; 0.63-24.10 µg eq. Tx/g, 1.61-40.82 µg eq. Tx/g and 1.89-68.54 µg eq. Tx/g, respectively), and significantly reduced ROS production in human hepatoma cells. In addition, mixtures of honey with 10% of propolis improved the results obtained with natural honey, increasing the value of total phenolic content and antioxidant capacity. A significant positive correlation was observed between total phenolic compounds and antioxidant capacity. Therefore, the antioxidant capacity could be attributed to the phenolic compounds present in the samples, at least partially. In conclusion, our results indicated that thyme and chestnut honey supplemented with propolis can be an excellent natural source of antioxidants and could be incorporated as a potential food ingredient with biological properties of technological interest, added as a preservative. Moreover, these mixtures could be used as natural sweeteners enriched in antioxidants and other bioactive compounds.

10.
Sci Adv ; 8(29): eabj9138, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35857834

RESUMO

SRY (sex determining region Y)-box 2 (SOX2)-labeled cells play key roles in chemoresistance and tumor relapse; thus, it is critical to elucidate the mechanisms propagating them. Single-cell transcriptomic analyses of the most common malignant pediatric brain tumor, medulloblastoma (MB), revealed the existence of astrocytic Sox2+ cells expressing sonic hedgehog (SHH) signaling biomarkers. Treatment with vismodegib, an SHH inhibitor that acts on Smoothened (Smo), led to increases in astrocyte-like Sox2+ cells. Using SOX2-enriched MB cultures, we observed that SOX2+ cells required SHH signaling to propagate, and unlike in the proliferative tumor bulk, the SHH pathway was activated in these cells downstream of Smo in an MYC-dependent manner. Functionally different GLI inhibitors depleted vismodegib-resistant SOX2+ cells from MB tissues, reduced their ability to further engraft in vivo, and increased symptom-free survival. Our results emphasize the promise of therapies targeting GLI to deplete SOX2+ cells and provide stable tumor remission.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Meduloblastoma , Neoplasias Cerebelares/genética , Criança , Proteínas Hedgehog/metabolismo , Humanos , Meduloblastoma/genética , Meduloblastoma/patologia , Recidiva Local de Neoplasia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco/metabolismo
11.
Cell Oncol (Dordr) ; 45(3): 415-428, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35499815

RESUMO

PURPOSE: Chondrosarcoma and osteosarcoma are the most frequently occurring bone cancers. Although surgery and chemotherapy are currently clinically applied, improved treatment options are urgently needed. Melatonin is known to inhibit cell proliferation in both tumor types. Although the underlying mechanisms are not clear yet, calcium homeostasis has been reported to be a key factor in cancer biology. Here, we set out to investigate whether regulation of calcium by this indolamine may be involved in its antitumor effect. METHODS: Cell viability was measured using a MTT assay and flow cytometry was used to measure levels of cytosolic calcium, intracellular oxidants, mitochondrial membrane potential and cell cycle progression. Mitochondrial calcium was analyzed by fluorimetry. Cell migration was determined using a scratch wound-healing assay. Western blot analysis was used to assess the expression of proteins related to cell cycle progression, epithelial to mesenchymal transition (EMT), Ac-CoA synthesis and intracellular signaling pathways. RESULTS: We found that melatonin decreases cytosolic and mitochondrial Ca2+ levels, intracellular oxidant levels, mitochondrial function and the expression of the E1 subunit of the pyruvate dehydrogenase complex. These changes were found to be accompanied by decreases in cell proliferation, cell migration and EMT marker expression. The addition of CaCl2 prevented the changes mentioned above, while co-treatment with the calcium chelator BAPTA enhanced the effects. CONCLUSIONS: Our data indicate that regulation of calcium homeostasis is a key factor in the inhibition of cell proliferation and migration by melatonin. This effect should be taken into consideration in combined therapies with traditional or new antitumor compounds, since it may circumvent therapy resistance.


Assuntos
Neoplasias Ósseas , Melatonina , Osteossarcoma , Neoplasias de Tecidos Moles , Neoplasias Ósseas/patologia , Cálcio/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Humanos , Melatonina/farmacologia , Melatonina/uso terapêutico , Osteossarcoma/patologia
12.
Cells ; 11(2)2022 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-35053415

RESUMO

Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a neurodegenerative disorder commonly diagnosed in infants and characterized by progressive cerebellar ataxia, spasticity, motor sensory neuropathy and axonal demyelination. ARSACS is caused by mutations in the SACS gene that lead to truncated or defective forms of the 520 kDa multidomain protein, sacsin. Sacsin function is exclusively studied on neuronal cells, where it regulates mitochondrial network organization and facilitates the normal polymerization of neuronal intermediate filaments (i.e., neurofilaments and vimentin). Here, we show that sacsin is also highly expressed in astrocytes, C6 rat glioma cells and N9 mouse microglia. Sacsin knockout in C6 cells (C6Sacs-/-) induced the accumulation of the glial intermediate filaments glial fibrillary acidic protein (GFAP), nestin and vimentin in the juxtanuclear area, and a concomitant depletion of mitochondria. C6Sacs-/- cells showed impaired responses to oxidative challenges (Rotenone) and inflammatory stimuli (Interleukin-6). GFAP aggregation is also associated with other neurodegenerative conditions diagnosed in infants, such as Alexander disease or Giant Axonal Neuropathy. Our results, and the similarities between these disorders, reinforce the possible connection between ARSACS and intermediate filament-associated diseases and point to a potential role of glia in ARSACS pathology.


Assuntos
Deleção de Genes , Filamentos Intermediários/metabolismo , Chaperonas Moleculares/metabolismo , Neuroglia/metabolismo , Animais , Animais Recém-Nascidos , Linhagem Celular Tumoral , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Rotenona/toxicidade
13.
Life Sci ; 278: 119597, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33974932

RESUMO

This brief review describes the association of the endogenous pineal melatonin rhythm with the metabolic flux of solid tumors, particularly breast cancer. It also summarizes new information on the potential mechanisms by which endogenously-produced or exogenously-administered melatonin impacts the metabolic phenotype of cancer cells. The evidence indicates that solid tumors may redirect their metabolic phenotype from the pathological Warburg-type metabolism during the day to the healthier mitochondrial oxidative phosphorylation on a nightly basis. Thus, they function as cancer cells only during the day and as healthier cells at night, that is, they are only part-time cancerous. This switch to oxidative phosphorylation at night causes cancer cells to exhibit a reduced tumor phenotype and less likely to rapidly proliferate or to become invasive or metastatic. Also discussed is the likelihood that some solid tumors are especially aggressive during the day and much less so at night due to the nocturnal rise in melatonin which determines their metabolic state. We further propose that when melatonin is used/tested in clinical trials, a specific treatment paradigm be used that is consistent with the temporal metabolic changes in tumor metabolism. Finally, it seems likely that the concurrent use of melatonin in combination with conventional chemotherapies also would improve cancer treatment outcomes.


Assuntos
Melatonina/metabolismo , Neoplasias/metabolismo , Efeito Warburg em Oncologia , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Melatonina/farmacologia , Melatonina/uso terapêutico , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fosforilação Oxidativa/efeitos dos fármacos , Efeito Warburg em Oncologia/efeitos dos fármacos
14.
J Cell Physiol ; 236(1): 27-40, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32725819

RESUMO

Several oncogenic pathways plus local microenvironmental conditions, such as hypoxia, converge on the regulation of cancer cells metabolism. The major metabolic alteration consists of a shift from oxidative phosphorylation as the major glucose consumer to aerobic glycolysis, although most of cancer cells utilize both pathways to a greater or lesser extent. Aerobic glycolysis, together with the directly related metabolic pathways such as the tricarboxylic acid cycle, the pentose phosphate pathway, or gluconeogenesis are currently considered as therapeutic targets in cancer research. Melatonin has been reported to present numerous antitumor effects, which result in a reduced cell growth. This is achieved with both low and high concentrations with no relevant side effects. Indeed, high concentrations of this indolamine reduce proliferation of cancer types resistant to low concentrations and induce cell death in some types of tumors. Previous work suggest that regulation of glucose metabolism and other related pathways play an important role in the antitumoral effects of high concentration of melatonin. In the present review, we analyze recent work on the regulation by such concentrations of this indolamine on aerobic glycolysis, gluconeogenesis, the tricarboxylic acid cycle and the pentose phosphate pathways of cancer cells.


Assuntos
Glucose/metabolismo , Melatonina/administração & dosagem , Neoplasias/metabolismo , Animais , Carcinogênese/efeitos dos fármacos , Carcinogênese/metabolismo , Proliferação de Células/efeitos dos fármacos , Gluconeogênese/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos
15.
Oncol Rep ; 44(1): 293-302, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32319665

RESUMO

The FMS­like tyrosine kinase 3 internal tandem duplication (FLT3­ITD) mutation represents the most frequent genetic alteration in acute myeloid leukemia (AML) and is associated with poor prognosis. The mutation promotes cancer cell survival and proliferation, and shifts their glucose metabolism towards aerobic glycolysis, a frequent alteration in cancer. In the present study, the impact of melatonin on the viability of AML cell lines with (MV­4­11 and MOLM­13) or without the FLT3­ITD mutation (OCI­AML3 and U­937) was evaluated. Melatonin induces cell death in AML cells carrying the FLT3­ITD mutation, but only inhibits the proliferation of AML cells without this mutation. Consistently, melatonin decreases tumor growth and increases animal survival in a xenograft model of FLT3­ITD AML. Toxicity is related to a decrease in glucose uptake, lactate dehydrogenase activity, lactate production and hypoxia­inducible factor­1α activation. Melatonin also regulates the expression of glucose metabolism­related genes, impairing the balance between anaplerosis and cataplerosis, through the upregulation of the expression of phosphoenolpyruvate carboxykinase 2 (PCK2). Collectively, the present findings highlight the regulation of glucose metabolism, currently considered a possible therapeutic target in cancer, as a key event in melatonin­induced cytotoxicity, suggesting its potential as a therapeutic tool for the treatment of patients with AML, particularly those carrying the FLT3­ITD mutation that results in low basal expression levels of PCK2.


Assuntos
Glucose/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Melatonina/administração & dosagem , Mutação , Tirosina Quinase 3 Semelhante a fms/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Melatonina/farmacologia , Camundongos , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
FASEB Bioadv ; 2(2): 116-125, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32123861

RESUMO

Signal transducer and activator of transcription 3 (STAT3) is a ubiquitous and pleiotropic transcription factor that plays essential roles in normal development, immunity, response to tissue damage and cancer. We have developed a Venus-STAT3 bimolecular fluorescence complementation assay that allows the visualization and study of STAT3 dimerization and protein-protein interactions in living cells. Inactivating mutations on residues susceptible to post-translational modifications (PTMs) (K49R, K140R, K685R, Y705F and S727A) changed significantly the intracellular distribution of unstimulated STAT3 dimers when the dimers were formed by STAT3 molecules that carried different mutations (ie they were "asymmetric"). Some of these asymmetric dimers changed the proliferation rate of HeLa cells. Our results indicate that asymmetric PTMs on STAT3 dimers could constitute a new level of regulation of STAT3 signaling. We put forward these observations as a working hypothesis, since confirming the existence of asymmetric STAT3 homodimers in nature is extremely difficult, and our own experimental setup has technical limitations that we discuss. However, if our hypothesis is confirmed, its conceptual implications go far beyond STAT3, and could advance our understanding and control of signaling pathways.

17.
Front Pharmacol ; 10: 935, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31551765

RESUMO

α-Hispanolol (α-H) is a labdane diterpenoid that has been shown to induce apoptosis in several human cancer cells. However, the effect of α-H in human glioblastoma cells has not been described. In the present work, we have investigated the effects of α-H on apoptosis, migration, and invasion of human glioblastoma cells with the aim of identifying the molecular targets underlying its mechanism of action. The results revealed that α-H showed significant cytotoxicity against human glioma cancer cell lines U87 and U373 in a concentration- and time-dependent manner. This effect was higher in U87 cells and linked to apoptosis, as revealed the increased percentage of sub-G1 population by cell cycle analysis and acquisition of typical features of apoptotic cell morphology. Apoptosis was also confirmed by significant presence of annexin V-positive cells and caspase activation. Pretreatment with caspase inhibitors diminishes the activities of caspase 8, 9, and 3 and maintains the percentage of viable glioblastoma cells, indicating that α-H induced cell apoptosis through both the extrinsic and the intrinsic pathways. Moreover, we also found that α-H downregulated the anti-apoptotic Bcl-2 and Bcl-xL proteins and activated the pro-apoptotic Bid and Bax proteins. On the other hand, α-H exhibited inhibitory effects on the migration and invasion of U87 cells in a concentration-dependent manner. Furthermore, additional experiments showed that α-H treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase MMP-2 and MMP-9 and increased the expression of TIMP-1 inhibitor, probably via p38MAPK regulation. Finally, xenograft assays confirmed the anti-glioma efficacy of α-H. Taken together, these findings suggest that α-H may exert anti-tumoral effects in vitro and in vivo through the inhibition of cell proliferation and invasion as well as by the induction of apoptosis in human glioblastoma cells. This research describes α-H as a new drug that may improve the therapeutic efficacy against glioblastoma tumors.

18.
J Orthop Surg Res ; 14(1): 121, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31068197

RESUMO

BACKGROUND: Metatarsalgia of the lesser toes is a common cause of consultation in the podiatric clinic. However, there continues to be a controversy with respect to which is the best surgical technique, and there is few information in the literature regarding objectively comparable results in percutaneous surgery. METHODS: The second metatarsal bones of 30 feet belonging to patients who had attended the podiatric clinic were studied before and after distal metatarsal pecutaneous osteotomy. The degree of shortening of the second metatarsal (RX) and the degree of functional recovery and perception of the well-being of the patient (AOFAS) were evaluated retrospectively. The same bones of 10 cadaveric feet were also studied. The surgical procedure was identical to that used on patients, and electronic callipers were employed to take measurements of the second metatarsal. The integrity of the plantar plate was checked visually. RESULTS: The mean shortening of the second metatarsal bone, as determined by the radiological study, was 2.76 mm. After an average follow-up period of 1.5 years, the final mean score on the AOFAS scale was 95.26 points. In none of the cases was the mobility of the metatarsophalangeal (MTP) joint affected. The mean shortening in the cadaveric feet was 2.10 mm, and in all cases, the plantar plate and flexor apparatus were perfectly preserved. CONCLUSIONS: Percutaneous osteotomy achieved, in our study, a lower degree of shortening than Weil's surgery, according to the data published in the literature. However, it shows good clinical results without causing problems of consolidation or rigidity in the MTP joint. Neither, with the caution that should be taken due to the use of experimental cadaver models, damage of the flexor apparatus of the foot is observed. These results suggest that this could be a safe and effective surgical procedure to be considered for metatarsalgias of the lesser rays.


Assuntos
Ossos do Metatarso/cirurgia , Metatarsalgia/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/tendências , Osteotomia/tendências , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Ossos do Metatarso/diagnóstico por imagem , Metatarsalgia/diagnóstico por imagem , Articulação Metatarsofalângica/diagnóstico por imagem , Articulação Metatarsofalângica/cirurgia , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Osteotomia/métodos , Estudos Retrospectivos , Resultado do Tratamento
19.
Mol Cancer Ther ; 17(3): 614-624, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29339551

RESUMO

Internal tandem duplication (ITD) or tyrosine kinase domain mutations of FLT3 is the most frequent genetic alteration in acute myelogenous leukemia (AML) and are associated with poor disease outcome. Despite considerable efforts to develop single-target FLT3 drugs, so far, the most promising clinical response has been achieved using the multikinase inhibitor midostaurin. Here, we explore the activity of the indolocarbazole EC-70124, from the same chemical space as midostaurin, in preclinical models of AML, focusing on those bearing FLT3-ITD mutations. EC-70124 potently inhibits wild-type and mutant FLT3, and also other important kinases such as PIM kinases. EC-70124 inhibits proliferation of AML cell lines, inducing cell-cycle arrest and apoptosis. EC-70124 is orally bioavailable and displays higher metabolic stability and lower human protein plasma binding compared with midostaurin. Both in vitro and in vivo pharmacodynamic analyses demonstrate inhibition of FLT3-STAT5, Akt-mTOR-S6, and PIM-BAD pathways. Oral administration of EC-70124 in FLT3-ITD xenograft models demonstrates high efficacy, reaching complete tumor regression. Ex vivo, EC-70124 impaired cell viability in leukemic blasts, especially from FLT3-ITD patients. Our results demonstrate the ability of EC-70124 to reduce proliferation and induce cell death in AML cell lines, patient-derived leukemic blast and xenograft animal models, reaching best results in FLT3 mutants that carry other molecular pathways' alterations. Thus, its unique inhibition profile warrants EC-70124 as a promising agent for AML treatment based on its ability to interfere the complex oncogenic events activated in AML at several levels. Mol Cancer Ther; 17(3); 614-24. ©2018 AACR.


Assuntos
Carbazóis/farmacologia , Indóis/farmacologia , Leucemia Mieloide/tratamento farmacológico , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Doença Aguda , Animais , Disponibilidade Biológica , Células CACO-2 , Carbazóis/farmacocinética , Carbazóis/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Feminino , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Indóis/farmacocinética , Indóis/uso terapêutico , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Camundongos SCID , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-pim-1/genética , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Células THP-1 , Tirosina Quinase 3 Semelhante a fms/metabolismo
20.
Mol Cell Endocrinol ; 434: 238-49, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27402602

RESUMO

Melatonin (N-acetyl-5-methoxytryptamine) is a highly pleiotropic hormone with antioxidant, antiproliferative, oncolytic and neuroprotective properties. Here, we present evidence that the N-acetyl side chain plays a key role in melatonin's antiproliferative effect in HT22 and sw-1353 cells, but it does so at the expense of antioxidant and neuroprotective properties. Removal of the N-acetyl group enhances the antioxidant and neuroprotective properties of the indole, but it can lead to toxic methamphetamine-like effects in several cell lines. Inhibition of NFkB mimicked melatonin's antiproliferative and antioxidant effects, but not neuroprotection. Our results strongly suggest that neuroprotective and antiproliferative effects of melatonin rely on different parts of the molecule and are likely mediated by different mechanisms. We also predict that melatonin metabolism by target cells could determine whether melatonin inhibits cell proliferation, prevents toxicity or induces cell death (e.g. apoptosis or autophagy). These observations could have important implications for the rational use of melatonin in personalized medicine.


Assuntos
Antioxidantes/farmacologia , Ácido Glutâmico/toxicidade , Hipocampo/efeitos dos fármacos , Melatonina/farmacologia , Fármacos Neuroprotetores/farmacologia , 5-Metoxitriptamina , Animais , Autofagia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HEK293 , Hipocampo/citologia , Humanos , Camundongos
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