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1.
Med Oncol ; 39(5): 52, 2022 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-35150326

RESUMO

Light-emitting diode (LED)-based therapies, particularly blue LEDs with wavelengths of 400-500 nm, have shown beneficial results in several cancers, including melanoma, lymphoid cells, and skin tumors. In this study, the cell viability and apoptosis of Kasumi-1 cells treated by blue light (BL) irradiation have been explored. Firstly, BL can specially inhibit the proliferation and promote the apoptosis of Kasumi-1 cells. Furthermore, the apoptosis was triggered by the production of reactive oxygen species and the decline of mitochondrial membrane potential which was regulated by the ratio of Bcl-2(Bcl-xL)/Bax; BL caused the cells' final apoptosis accompanied with the increased cleavage of caspase-3 and poly-ADP-ribose polymerase. Finally, BL induced the degradation of AML1-ETO dependent on the activation of caspase-3. These results are helpful for establishing a low toxicity and high efficiency strategy of BL irradiation for clinical treatment of Kasumi-1 cells.


Assuntos
Apoptose/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Potencial da Membrana Mitocondrial/efeitos da radiação , Proteínas de Fusão Oncogênica/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Caspase 3/metabolismo , Linhagem Celular Tumoral , Cor , Subunidade alfa 2 de Fator de Ligação ao Core/efeitos da radiação , Humanos , Proteínas de Fusão Oncogênica/efeitos da radiação , Estimulação Luminosa/métodos , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína 1 Parceira de Translocação de RUNX1/efeitos da radiação
2.
Asian Pac J Cancer Prev ; 23(2): 383-388, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35225447

RESUMO

BACKGROUND: Preclinical development of new drugs for cancer immunotherapy requires preconditioning total body irradiation (TBI) of mice to be humanized via hematopoietic stem cell transplantation. To assess the effect of preconditioning TBI, we detected the reactive oxygen species (ROS), Annexin V, propidium iodide (PI) level in bone marrow samples by flow cytometer. METHODS: We divided all NOG mice between irradiated (n = 20) and control groups (n = 10) for two time points. Irradiated mice were exposed to 3.5 Gy of radiation. After sacrificing BM samples were collected, the flow cytometric percentage of ROS, Annexin V, and PI markers were investigated on days 2 and 14 after exposure. RESULTS: At the first time point, the level of ROS was higher in the irradiated group than in the control group, and this difference was statistically significant (P < 0.05). Also, at the second time point, the mean differences of all markers in the irradiated group were significantly compared to the control group (P < 0.05). CONCLUSION: Thus, in NOG mice, the measurement of ROS level is helpful to the assessment of preconditioning TBI.


Assuntos
Citometria de Fluxo , Espécies Reativas de Oxigênio/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Animais , Anexina A5/efeitos da radiação , Medula Óssea/efeitos da radiação , Transplante de Células-Tronco Hematopoéticas , Camundongos , Propídio/efeitos da radiação
3.
J Med Chem ; 65(4): 3632-3643, 2022 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-35164509

RESUMO

Targeted protein degradation technologies (e.g., PROTACs) that can selectively degrade intracellular protein are an emerging class of promising therapeutic modalities. Herein, we describe the conjugation of photosensitizers and protein ligands (PS-Degrons), as an activable targeted protein degradation platform. PS-Degrons are capable of degrading protein of interest via light-triggered 1O2, which is orthogonal and complementary to existing technologies. This generalizable platform allows controllable knockdown of the target protein with high spatiotemporal precision. Our lead compound PSDalpha induces a complete degradation of human estrogen receptor α (ERα) under visible light. The high degrading ERα efficacy of PSDalpha enables an excellent anti-proliferation performance on MCF-7 cells. Our results establish a modular strategy for the controllable degradation of target proteins, which can hopefully overcome the systemic toxicity in clinical treatment of PROTACs. We anticipate that PS-Degrons would open a new chapter for biochemical research and for the therapeutics.


Assuntos
Proteínas/efeitos da radiação , Espécies Reativas de Oxigênio/química , Espécies Reativas de Oxigênio/efeitos da radiação , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Ligantes , Luz , Células MCF-7 , Modelos Moleculares , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/farmacologia , Proteínas/química , Ubiquitina-Proteína Ligases
4.
J Insect Sci ; 21(5)2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34718645

RESUMO

Radiation is considered as a promising insect pest control strategy for minimizing postharvest yield losses. Among various techniques, irradiation is a method of choice as it induces lethal biochemical or molecular changes that cause a downstream cascade of abrupt physiological abnormalities at the cellular level. In this study, we evaluated the effect of 60Co-γ radiation on various developmental stages of Zeugodacus cucurbitae Coquillett and subsequent carry-over effects on the progeny. For this purpose, we treated eggs with 30- and 50-Gy radiation doses of 60Co-γ. We found that radiation significantly affected cellular antioxidants, insect morphology, and gene expression profiles. Our results indicate that in response to various doses of irradiation reactive oxygen species, catalase, peroxidase, and superoxide dismutase activities were increased along with a significant increase in the malondialdehyde (MDA) content. We observed higher mortality rates during the pupal stage of the insects that hatched from irradiated eggs (50 Gy). Furthermore, the life span of the adults was reduced in response to 50 Gy radiation. The negative effects carried over to the next generation were marked by significantly lower fecundity in the F1 generation of the irradiation groups as compared to control. The radiation induced morphological abnormalities at the pupal, as well as the adult, stages. Furthermore, variations in the gene expression following irradiation are discussed. Taken together, our results signify the utility of 60Co-γ radiation for fruit fly postharvest management.


Assuntos
Apoptose/efeitos da radiação , Raios gama , Expressão Gênica/efeitos da radiação , Tephritidae/efeitos da radiação , Animais , Antioxidantes/metabolismo , Antioxidantes/efeitos da radiação , Apoptose/genética , Catalase/metabolismo , Catalase/efeitos da radiação , Radioisótopos de Cobalto/farmacologia , Controle de Insetos/métodos , Proteínas de Insetos/metabolismo , Proteínas de Insetos/efeitos da radiação , Larva/genética , Larva/metabolismo , Larva/fisiologia , Larva/efeitos da radiação , Longevidade/efeitos da radiação , Malondialdeído/metabolismo , Malondialdeído/efeitos da radiação , Peroxidase/metabolismo , Peroxidase/efeitos da radiação , Controle de Pragas/métodos , Pupa/genética , Pupa/metabolismo , Pupa/fisiologia , Pupa/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Tephritidae/genética , Tephritidae/metabolismo , Tephritidae/fisiologia
5.
Int J Mol Sci ; 22(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34681819

RESUMO

Non-ionizing radiation is commonly used in the clinical setting, despite its known ability to trigger oxidative stress and apoptosis, which can lead to damage and cell death. Although induction of cell death is typically considered harmful, apoptosis can also be beneficial in the right context. For example, cell death can serve as the signal for new tissue growth, such as in apoptosis-induced proliferation. Recent data has shown that exposure to non-ionizing radiation (such as weak static magnetic fields, weak radiofrequency magnetic fields, and weak electromagnetic fields) is able to modulate proliferation, both in cell culture and in living organisms (for example during tissue regeneration). This occurs via in vivo changes in the levels of reactive oxygen species (ROS), which are canonical activators of apoptosis. This review will describe the literature that highlights the tantalizing possibility that non-ionizing radiation could be used to manipulate apoptosis-induced proliferation to either promote growth (for regenerative medicine) or inhibit it (for cancer therapies). However, as uncontrolled growth can lead to tumorigenesis, much more research into this exciting and developing area is needed in order to realize its promise.


Assuntos
Apoptose/efeitos da radiação , Proliferação de Células/efeitos da radiação , Radiação não Ionizante , Espécies Reativas de Oxigênio/efeitos da radiação , Animais , Protocolos Antineoplásicos , Humanos , Medicina Regenerativa
6.
J Neurooncol ; 152(2): 245-255, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33566263

RESUMO

BACKGROUND: Radiotherapy-induced tumor death remains critical in the successful first-line management of glioblastoma, whereas resistance to radiation serves as a major factor in disease progression. Mesenchymal shift has been identified as a driver in GBM recurrence, with gene expression associated with enhanced repair of macromolecular damage caused by radiation. METHODS: Using distinct mesenchymal subtype GBM cells lines, radiation response was assessed by clonogenic assay and orthotopic mouse tumor model. RNA-sequencing was performed in the setting of increasing radiation dosing while real-time assessment of ROS generation was achieved by the measurement of hydroxyl spin trap adducts via electron paramagnetic resonance. RESULTS: Radiation-induced cell death determined by clonogenic assay was significantly different at low dose (4-8 Gy) between the resistant U3035 cells and the sensitive U3020 cells. Similar trends were present in the in vivo NSG mouse model following radiation dosing on post-implantation day 7-10, with the rate of reduction in tumor bioluminescence reversing between the U3020 and U3035 cells after the third dose of radiation. Changes in gene expression following radiation determined by RNA-sequencing indicate both U3035 and U3020 cells demonstrate a shift toward more mesenchymal profiles, with concurrent shift away from pro-neural subtype gene expression in the U3020 cells that appeared to develop resistance to radiation in vivo. Persistence of ROS generated following radiation was greater in U3020 cells shown to be more sensitive to radiation. CONCLUSIONS: Despite the same molecular classification, distinct GBM cell lines can demonstrate differential response to radiation and potential for mesenchymal shift associated with radiation resistance.


Assuntos
Neoplasias Encefálicas/patologia , Glioblastoma/patologia , Tolerância a Radiação/fisiologia , Espécies Reativas de Oxigênio/efeitos da radiação , Transcriptoma/efeitos da radiação , Animais , Linhagem Celular Tumoral , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
J Photochem Photobiol B ; 216: 112143, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33550219

RESUMO

A new silicon phthalocyanine with piperazine-furan ring and its quaternized form were synthesized. All compounds were analyzed by spectroscopic techniques (FT-IR, 1H-NMR, MS, and UV-vis), and the absorbance characteristics of silicon phthalocyanines were evaluated with the expected strong typical absorption bands in the far-red spectrum. The cytotoxic effects of these phthalocyanines induced by photodynamic therapy (PDT) were determined in a dose-dependent manner. Following cytotoxicity analysis, flow cytometric research of cell death was performed. The formation of reactive oxygen species (ROS) was determined by confocal microscopy. High levels of cytotoxicity and decreased viable cell population have been detected in cancer cells after treatment. In addition, ROS formation was observed in PDT treated cancer cells. However, low levels of cell death and ROS formation were observed in non-tumorigenic cells. According to western blot data, PDT-mediated treatment was found to provide different expression patterns of the cleaved PARP1 protein. The presented study demonstrates that PDT-mediated treatment of newly synthesized phthalocyanines has significant anti-cancer effects on breast cancer cells and may induce different cell death pathways.


Assuntos
Antineoplásicos/química , Neoplasias da Mama/terapia , Indóis/química , Compostos de Organossilício/química , Fármacos Fotossensibilizantes/química , Piperazina/química , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Indóis/farmacologia , Imagem Óptica , Compostos de Organossilício/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação
8.
Oxid Med Cell Longev ; 2021: 5826932, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35028001

RESUMO

Glutamine metabolism provides energy to tumor cells and also produces reactive oxygen species (ROS). Excessive accumulation of ROS can damage mitochondria and eventually lead to cell death. xCT (SLC7A11) is responsible for the synthesis of glutathione in order to neutralize ROS. In addition, mitophagy can remove damaged mitochondria to keep the cell alive. Ionizing radiation kills tumor cells by causing the accumulation of ROS, which subsequently induces nuclear DNA damage. With this in mind, we explored the mechanism of intracellular ROS accumulation induced by ionizing radiation and hypothesized new methods to enhance the effect of radiotherapy. We used MCF-7 breast cancer cells and HCT116 colorectal cancer cells in our study. The above-mentioned cells were irradiated with different doses of X-rays or carbon ions. Clone formation assays were used to detect cell proliferation, enzyme-linked immunosorbent assay (ELISA) detected ATP, and glutathione (GSH) production, while the expression of proteins was detected by Western blot and quantitative real-time PCR analysis. The production of ROS was detected by flow cytometry, and immunofluorescence was used to track mitophagy-related processes. Finally, BALB/C tumor-bearing nude mice were irradiated with X-rays in order to further explore the protein expression found in tumors with the use of immunohistochemistry. Ionizing radiation increased the protein expressions of ASCT2, GLS, and GLUD in order to upregulate the glutamine metabolic flux in tumor cells. This caused an increase in ATP secretion. Meanwhile, ionizing radiation inhibited the expression of the xCT (SLC7A11) protein and reduced the generation of glutathione, leading to excessive accumulation of intracellular ROS. The mitophagy inhibitor, or knockdown Parkin gene, is able to enhance the ionizing radiation-induced ROS production and increase nucleus DNA damage. This combined treatment can significantly improve the killing effect of radiation on tumor cells. We concluded that ionizing radiation could upregulate the glutamine metabolic flux and enhance ROS accumulation in mitochondria. Ionizing radiation also decreased the SLC7A11 expression, resulting in reduced GSH generation. Therefore, inhibition of mitophagy can increase ionizing radiation-induced cell death.


Assuntos
Morte Celular/efeitos da radiação , Glutamina/metabolismo , Glutamina/efeitos da radiação , Radiação Ionizante , Espécies Reativas de Oxigênio/efeitos da radiação , Animais , Feminino , Humanos , Camundongos , Camundongos Nus , Regulação para Cima
9.
J Photochem Photobiol B ; 214: 112088, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33278762

RESUMO

Low level light therapy uses light of specific wavelengths in red and near-infrared spectral range to treat various pathological conditions. This light is able to modulate biochemical cascade reactions in cells that can have important health implications. In this study, the effect of low intensity light at 650, 808 and 1064 nm on neurons and two types of cancer cells (neuroblastoma and HeLa) is reported, with focus on the photoinduced change of intracellular level of Ca2+ ions and corresponding signaling pathways. The obtained results show that 650 and 808 nm light promotes intracellular Ca2+ elevation regardless of cell type, but with different dynamics due to the specificities of Ca2+ regulation in neurons and cancer cells. Two origins responsible for Ca2+ elevation are determined to be: influx of exogenous Ca2+ ions into cells and Ca2+ release from endoplasmic reticulum. Our investigation of the related cellular processes shows that light-induced membrane depolarization is distinctly involved in the mechanism of Ca2+ influx. Ca2+ release from endoplasmic reticulum activated by reactive oxygen species generation is considered as a possible light-dependent signaling pathway. In contrast to the irradiation with 650 and 808 nm light, no effects are observed under 1064 nm irradiation. We believe that the obtained insights are of high significance and can be useful for the development of drug-free phototherapy.


Assuntos
Sinalização do Cálcio/efeitos da radiação , Cálcio/efeitos da radiação , Retículo Endoplasmático/metabolismo , Retículo Endoplasmático/efeitos da radiação , Cálcio/fisiologia , Membrana Celular/metabolismo , Eletrofisiologia , Corantes Fluorescentes/química , Células HeLa , Humanos , Raios Infravermelhos , Terapia com Luz de Baixa Intensidade , Neurônios/efeitos da radiação , Imagem Óptica , Espécies Reativas de Oxigênio/efeitos da radiação
10.
Int J Radiat Oncol Biol Phys ; 109(5): 1440-1453, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33186615

RESUMO

PURPOSE: To investigate whether the vascular collapse in tumors by conventional dose rate (CONV) irradiation (IR) would also occur by the ultra-high dose rate FLASH IR. METHODS AND MATERIALS: Lewis lung carcinoma (LLC) cells were subcutaneously implanted in mice. This was followed by CONV or FLASH IR at 15 Gy. Tumors were harvested at 6 or 48 hours after IR and stained for CD31, phosphorylated myosin light chain (p-MLC), γH2AX (a surrogate marker for DNA double strand break), intracellular reactive oxygen species (ROS), or immune cells such as myeloid and CD8α T cells. Cell lines were irradiated with CONV IR for Western blot analyses. ML-7 was intraperitoneally administered daily to LLC-bearing mice for 7 days before 15 Gy CONV IR. Tumors were similarly harvested and analyzed. RESULTS: By immunostaining, we observed that CONV IR at 6 hours resulted in constricted vessel morphology, increased expression of p-MLC, and much higher numbers of γH2AX-positive cells in tumors, which were not observed with FLASH IR. Mechanistically, MLC activation by ROS is unlikely, because FLASH IR produced significantly more ROS than CONV IR in tumors. In vitro studies demonstrated that ML-7, an inhibitor of MLC kinase, abrogated IR-induced γH2AX formation and disappearance kinetics. Lastly, we observed that CONV IR when combined with ML-7 produced some effects similar to FLASH IR, including reduction in the vasculature collapse, fewer γH2AX-positive cells, and increased immune cell influx to the tumors. CONCLUSIONS: FLASH IR produced novel changes in the tumor microenvironment that were not observed with CONV IR. We believe that MLC activation in tumors may be responsible for some of the microenvironmental changes differentially regulated between CONV and FLASH IR.


Assuntos
Carcinoma Pulmonar de Lewis/radioterapia , Cadeias Leves de Miosina/efeitos da radiação , Microambiente Tumoral/efeitos da radiação , Animais , Azepinas/administração & dosagem , Vasos Sanguíneos/patologia , Vasos Sanguíneos/efeitos da radiação , Linfócitos T CD8-Positivos/citologia , Carcinoma Pulmonar de Lewis/irrigação sanguínea , Carcinoma Pulmonar de Lewis/metabolismo , Histonas/metabolismo , Histonas/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Cadeias Leves de Miosina/antagonistas & inibidores , Cadeias Leves de Miosina/metabolismo , Naftalenos/administração & dosagem , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Molécula-1 de Adesão Celular Endotelial a Plaquetas/efeitos da radiação , Radioterapia/métodos , Dosagem Radioterapêutica , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação
11.
J Ethnopharmacol ; 269: 113694, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33321189

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ultra Violet (UV) radiation is the major reason for reactive oxygen species (ROS) forming, skin cell damage, melanin production, and could horribly cause skin cancer. Saussureae Involucratae Herba (SIH) is the aerial part of Saussurea involucrata Matsum. & Koidz. This Material Medica is popular with both in Uyghur and Chinese medicines filed. SIH is one of the famous species of the Asteraceae family and which prescribed for skin protection from UV-induced damage according to China Pharmacopeia (2020). However, the detailed working mechanism involved is still not elucidated. AIM OF THE STUDY: We would like to probe the potential transduction pathway of SIH against UV-induced skin cell damages in cultured B16F10 cells. METHODS: Western blot, luciferase assay, laser confocal, RT-PCR and flow cytometer were employed here to verify the protective pharmaceutical value of SIH in cultured B16F10 cells after UV pre-treatment. RESULTS: Our result revealed that SIH attenuates ROS formation after UV-induced damage in B16F10 cells in a dose-dependent manner. Moreover, the transcriptional and translational anti-oxidative encoding genes were up-regulated under the presence of SIH. Further studies showed that SIH activated transcriptional activity of anti-oxidant response element (ARE). Moreover, we found that SIH dramatically stimulates PI3K/Akt phosphorylation in cultured B16F10 cells, this result was further verified by its specific inhibitors, LY294002 and Tocris. CONCLUSION: Our findings concluded that SIH protect melanoma cells from UV damages via activating PI3K/Akt signaling and which could provide scientific evidence for anti-UV pharmaceutical values of this herbal extract.


Assuntos
Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Saussurea , Transdução de Sinais/efeitos dos fármacos , Raios Ultravioleta/efeitos adversos , Animais , Melanoma Experimental , Camundongos , Fosfatidilinositol 3-Quinases/efeitos da radiação , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos da radiação
12.
Int J Mol Sci ; 21(21)2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-33139657

RESUMO

Here, we report the synthesis of a quantum dot (QD)-DNA covalent conjugate to be used as an H2O2-free DNAzyme system with oxidase activity. Amino-coupling conjugation was carried out between amino-modified oligonucleotides (CatG4-NH2) and carboxylated quantum dots (CdTe@COOH QDs). The obtained products were characterized by spectroscopic methods (UV-Vis, fluorescence, circular dichroizm (CD), and IR) and the transmission electron microscopy (TEM) technique. A QD-DNA system with a low polydispersity and high stability in aqueous solutions was successfully obtained. The catalytic activity of the QD-DNA conjugate was examined with Amplex Red and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate)) indicators using reactive oxygen species (ROS) generated by visible light irradiation. The synthesized QD-DNAzyme exhibited enhanced catalytic activity compared with the reference system (a mixture of QDs and DNAzyme). This proved the assumption that the covalent attachment of DNAzyme to the surface of QD resulted in a beneficial effect on its catalytic activity. The results proved that the QD-DNAzyme system can be used for generation of the signal by light irradiation. The light-induced oxidase activity of the conjugate was demonstrated, proving that the QD-DNAzyme system can be useful for the development of new cellular bioassays, e.g., for the determination of oxygen radical scavengers.


Assuntos
DNA Catalítico/metabolismo , Oxirredutases/metabolismo , Pontos Quânticos , Benzotiazóis/química , Benzotiazóis/metabolismo , DNA Catalítico/química , Luz , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/ultraestrutura , Oxazinas/química , Oxazinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Análise Espectral/métodos , Ácidos Sulfônicos/química , Ácidos Sulfônicos/metabolismo
13.
J Photochem Photobiol B ; 213: 112080, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33232882

RESUMO

Differential inherent and acquired radioresistance of human lung cancer cells contribute to poor therapeutic outcome and tumor recurrence after radiotherapy. Inherent radioresistance of lung cancer cells is known to be associated with ROSLow cancer stem cells (CSCs). However, mechanism of acquired radioresistance in lung cancer cells is poorly understood. Here, we exposed human lung cancer cells (A549) to a cumulative dose of 40Gy and allowed the radioresistant (RR) survivors to divide and form macroscopic colonies after each fraction of 5Gy dose. The RR subline exhibited enrichment of cytosolic ROSHigh cells without specific increase in mitochondrial ROS levels. We found a concomitant increase in the expression of redox regulatory transcription factor Nrf2 and its dependent antioxidant genes in RR cells and cell cycle delay as compared to parental cells. The treatment of RR cells with Nrf2 inhibitor resulted in decreased clonogenic survival indicating their addiction to Nrf2 for metabolic adaptations under high levels of cytosolic ROS. A causal role of inherent ROS levels in conferring radioresistance was established by sorting ROSHigh and ROSLow populations from parental and RR cells. It was observed that ROSHigh population from both parental and RR cells exhibited radioresistance as observed by clonogenic assay. Interestingly, ROSHigh population of cells exhibited higher levels of cellular thiols in both parental and RR cells. Thus, our observations highlight presence of a novel subpopulation in lung cancer cells, which exhibits radioresistance by maintaining 'oxidative stress' and Nrf2 dependent metabolic adaptations. We also posit Nrf2 pathway as a druggable target for radiosensitization of RR A549 cells.


Assuntos
Adaptação Fisiológica/efeitos da radiação , Radioisótopos de Cobalto/química , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Neoplasias Pulmonares/radioterapia , Estresse Oxidativo/efeitos da radiação , Células A549 , Antioxidantes/metabolismo , Apoptose/efeitos da radiação , Relação Dose-Resposta à Radiação , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Oxirredução , Tolerância a Radiação , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Compostos de Sulfidrila/metabolismo
14.
Biochem Pharmacol ; 182: 114205, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32828802

RESUMO

A continuous state of oxidative stress during inflammation contributes to the development of 25% of human cancers. Epithelial and inflammatory cells release reactive oxygen species (ROS) and reactive nitrogen species (RNS) that can damage DNA. ROS/RNS have biological implications in both chemoresistance and tumor recurrence. As several clinically employed anticancer drugs can generate ROS/RNS, we have addressed herein how inducible nitric oxide synthase and nitric oxide (iNOS/•NO) affect the molecular pathways implicated in the tumor response to oxidative stress. To mimic the oxidative stress associated with chemotherapy, we used a photosensitizer (pheophorbide a) that can generate ROS/RNS in a controlled manner. We investigated how iNOS/•NO modulates the tumor response to oxidative stress by involving the NF-κB and Nrf2 molecular pathways. We found that low levels of iNOS induce the development of a more aggressive tumor population, leading to survival, recurrence and resistance. By contrast, high levels of iNOS/•NO sensitize tumor cells to oxidative treatment, causing cell growth arrest. Our analysis showed that NF-κB and Nrf2, which are activated in response to oxidative stress, communicate with each other through RKIP. For this critical role, RKIP could be an interesting target for anticancer drugs. Our study provides insight into the complex signaling response of cancer cells to oxidative treatments as well as new possibilities for the rational design of new therapeutic strategies.


Assuntos
Óxido Nítrico/fisiologia , Estresse Oxidativo/fisiologia , Neoplasias da Próstata/metabolismo , Radiossensibilizantes/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Clorofila/análogos & derivados , Clorofila/toxicidade , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Humanos , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/efeitos da radiação , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/efeitos da radiação , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Neoplasias da Próstata/patologia , Espécies Reativas de Oxigênio/efeitos da radiação
15.
Health Phys ; 119(1): 101-108, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32483045

RESUMO

Ionizing radiation exposure produces direct or indirect biological effects on genomic DNA. The latter are ionizing radiation mediated by induction of free radicals and oxygen species (ROS). The study was conducted to evaluate the dose-effect/time-effect of antioxidant treatments in reducing the induction of double-strand breaks in human blood lymphocytes. Human peripheral blood samples of 2 mL each from healthy donors were irradiated with 10 mGy after pre-incubation with different antioxidants (ß-carotene, vitamin E, vitamin C, N-acetyl L-cysteine). In order to assess their efficiency as prophylactic therapy for irradiation, various concentrations and combinations of antioxidants, as well as different incubation times, have been evaluated. To assess double-strand breaks induced by ionizing radiation, the phosphorylated histone γ-H2AX has been used. A significant reduction (p < 0.001) in double-strand breaks studied with a γ-H2AX assay was observed with N-acetyl L-cysteine with a 1-h incubation time, followed by vitamin C, vitamin E, and ß-carotene. The use of antioxidants, especially N-acetyl L-cysteine before irradiation, significantly decreased the occurrence of double-strand breaks, demonstrating the potential radiological protection for exposure to ionizing radiation.


Assuntos
Antioxidantes/farmacologia , Células Sanguíneas/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , DNA/efeitos da radiação , Histonas/efeitos da radiação , Linfócitos/efeitos da radiação , Acetilcisteína/farmacologia , Ácido Ascórbico/farmacologia , Relação Dose-Resposta à Radiação , Histonas/genética , Humanos , Microscopia de Fluorescência , Doses de Radiação , Radiação Ionizante , Radiografia , Espécies Reativas de Oxigênio/efeitos da radiação , Vitamina E/farmacologia , Raios X , beta Caroteno/farmacologia
16.
Br J Cancer ; 123(1): 126-136, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32367071

RESUMO

BACKGROUND: Antioxidase alleviates the accumulation of radiation-induced reactive oxygen species (ROS) and therefore has strong connections with radioresistance. Isocitrate dehydrogenase 2 (IDH2) facilitates the turnover of antioxidase, but its role in radiotherapeutic efficiency in oesophageal squamous cell carcinoma (ESCC) still remains elusive. METHODS: The involvement of IDH2 in radiotherapeutic efficacy in ESCC was investigated in vitro and vivo by IDH2 knockdown. IDH2 expression in biopsy specimens of 141 patients was identified to evaluate its clinical significance. RESULTS: We found that Kyse510 and Kyse140 cells were more radioresistant and had higher IDH2 expression. In these two cell lines, IDH2 knockdown intensified the radiation-induced ROS overload and oxidative damage on lipid, protein, and nucleic acids. In addition, IDH2 silencing aggravated the radiation-induced mitochondrial dysfunction and cell apoptosis and ultimately promoted radiosensitisation via inhibiting AKT phosphorylation in a ROS-dependent manner. Furthermore, IDH2 depletion facilitated the radiation-induced growth inhibition and cell apoptosis in murine xenografts. Finally, IDH2 expression was correlated with definite chemoradiotherapy (dCRT) efficacy and served as an independent prognostic factor for survival of ESCC patients. CONCLUSIONS: IDH2 plays a key role in the radioresistance of ESCC. Targeting IDH2 could be a promising regimen to improve radiotherapeutic efficiency in ESCC patients.


Assuntos
Carcinoma de Células Escamosas do Esôfago/radioterapia , Isocitrato Desidrogenase/genética , Estresse Oxidativo/efeitos da radiação , Tolerância a Radiação/genética , Animais , Antioxidantes/metabolismo , Apoptose/efeitos da radiação , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Knockout , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Estresse Oxidativo/genética , Espécies Reativas de Oxigênio/efeitos da radiação
17.
Oxid Med Cell Longev ; 2020: 2576823, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32104530

RESUMO

UVA irradiation induced ROS-mediated photo damage to the human skin leading to coarseness, wrinkling, pigmentation, and cutaneous malignancies. We investigated the dermatoprotective efficacies of submicromolar concentrations of ergothioneine (EGT, 0.125-0.5 µM), which occurs naturally as a sulfur-containing amino acid, in the mechanisms in human skin fibroblast (HSF) cells. UVA-induced AP-1 (c-Fos and c-Jun) translocation was found to be inhibited by EGT treatments with the parallel inhibition of the collagenolytic matrix metalloproteinase- (MMP-) 1 activation and type I procollagen degradation. Moreover, EGT mitigated UVA-induced ROS generation. An increase in the amount of antioxidant genes (HO-1, NQO-1, and γ-GCLC) from EGT and were associated with upregulated Nrf2 expressions in a dose-dependent or time-dependent manner. We confirmed this from Nrf2 translocation and increased nuclear ARE promoter activity that underlie EGT dermatoprotective activities. Also, glutathione (GSH) levels (from γ-GCLC) were significantly increased. Moreover, we showed that mediated by ERK, JNK, and PKC, signaling cascades mediate Nrf2 translocation. We confirmed this phenomenon by the suppressed nuclear Nrf2 activation in cells that were treated with respective inhibitors (PD98059, SP600125, and GF109203X). However, antioxidant protein expressions were impaired in Nrf2 knockdown cells to confirm that ARE/Nrf2 pathways and the inhibition of AP-1 had significant roles in EGT-mediated protective effects. We can conclude that ergothioneine ameliorated UVA-induced skin aging and is a useful food supplement for skin care products.


Assuntos
Ergotioneína/farmacologia , Fibroblastos/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Envelhecimento da Pele/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismo , Antioxidantes/farmacologia , Linhagem Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Glutationa/metabolismo , Heme Oxigenase-1/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/genética , Pró-Colágeno/metabolismo , Proteína Quinase C/metabolismo , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Transdução de Sinais/genética , Fator de Transcrição AP-1/antagonistas & inibidores , Raios Ultravioleta , Regulação para Cima/efeitos dos fármacos
18.
FEBS Lett ; 594(2): 209-226, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31468514

RESUMO

Low Temperature Plasma (LTP) generates reactive oxygen and nitrogen species, causing cell death, similarly to radiation. Radiation resistance results in tumour recurrence, however mechanisms of LTP resistance are unknown. LTP was applied to patient-derived prostate epithelial cells and gene expression assessed. A typical global oxidative response (AP-1 and Nrf2 signalling) was induced, whereas Notch signalling was activated exclusively in progenitor cells. Notch inhibition induced expression of prostatic acid phosphatase (PAP), a marker of prostate epithelial cell differentiation, whilst reducing colony forming ability and preventing tumour formation. Therefore, if LTP is to be progressed as a novel treatment for prostate cancer, combination treatments should be considered in the context of cellular heterogeneity and existence of cell type-specific resistance mechanisms.


Assuntos
Gases em Plasma/uso terapêutico , Neoplasias da Próstata/radioterapia , Tolerância a Radiação/efeitos da radiação , Receptores Notch/genética , Fosfatase Ácida/genética , Morte Celular/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Células Epiteliais/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Masculino , Fator 2 Relacionado a NF-E2/genética , Gases em Plasma/efeitos adversos , Próstata/patologia , Próstata/efeitos da radiação , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Tolerância a Radiação/genética , Espécies Reativas de Nitrogênio/efeitos da radiação , Espécies Reativas de Oxigênio/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Células-Tronco/efeitos da radiação , Fator de Transcrição AP-1/genética
19.
Cytokine ; 125: 154777, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400640

RESUMO

Literature studies suggest important protective effects of low-frequency, low-energy pulsed electromagnetic fields (PEMFs) on inflammatory pathways affecting joint and cerebral diseases. However, it is not clear on which bases they affect neuroprotection and the mechanism responsible is yet unknown. Therefore the aim of this study was to identify the molecular targets of PEMFs anti-neuroinflammatory action. The effects of PEMF exposure in cytokine production by lipopolysaccharide (LPS)-activated N9 microglial cells as well as the pathways involved, including adenylyl cyclase (AC), phospholipase C (PLC), protein kinase C epsilon (PKC-ε) and delta (PKC-δ), p38, ERK1/2, JNK1/2 mitogen activated protein kinases (MAPK), Akt and caspase 1, were investigated. In addition, the ability of PEMFs to modulate ROS generation, cell invasion and phagocytosis, was addressed. PEMFs reduced the LPS-increased production of TNF-α and IL-1ß in N9 cells, through a pathway involving JNK1/2. Furthermore, they decreased the LPS-induced release of IL-6, by a mechanism not dependent on AC, PLC, PKC-ε, PKC-δ, p38, ERK1/2, JNK1/2, Akt and caspase 1. Importantly, a significant effect of PEMFs in the reduction of crucial cell functions specific of microglia like ROS generation, cell invasion and phagocytosis was found. PEMFs inhibit neuroinflammation in N9 cells through a mechanism involving, at least in part, the activation of JNK MAPK signalling pathway and may be relevant to treat a variety of diseases characterized by neuroinflammation.


Assuntos
Inflamação/metabolismo , Interleucina-1beta/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Microglia/efeitos da radiação , Fator de Necrose Tumoral alfa/metabolismo , Inibidores de Adenilil Ciclases/farmacologia , Adenilil Ciclases/metabolismo , Animais , Caspase 1/metabolismo , Linhagem Celular , Citocinas/metabolismo , Campos Eletromagnéticos , Interleucina-6/metabolismo , Janus Quinases/antagonistas & inibidores , Janus Quinases/metabolismo , Lipopolissacarídeos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Microglia/efeitos dos fármacos , Microglia/enzimologia , Microglia/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fagocitose/efeitos dos fármacos , Fagocitose/efeitos da radiação , Proteína Quinase C-delta/antagonistas & inibidores , Proteína Quinase C-delta/metabolismo , Proteína Quinase C-épsilon/antagonistas & inibidores , Proteína Quinase C-épsilon/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Eur J Pharm Biopharm ; 146: 101-110, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31841689

RESUMO

Previous studies have shown that curcumin (Cur) induced by ultrasound has protective effects on atherosclerosis even if low bioavailability of the Cur. The enhancement of bioavailability of the Cur further improved the curative effect of sonodynamic therapy (SDT) on atherosclerosis through nanotechnology. Nanosuspensions as a good drug delivery system had obvious advantages in increasing the solubility and improving the effectiveness of insoluble drugs. The aim of this study was to develop curcumin nanosuspensions (Cur-ns) which used polyvinylpyrrolidone (PVPK30) and sodium dodecyl sulfate (SDS) as stabilizers to improve poor water solubility and bioavailability of the Cur. And then the therapeutic effects of Cur-ns-SDT on atherosclerotic plaques and its possible mechanisms would be investigated and elucidated. Cur-ns with a small particle size has been successfully prepared and the data have confirmed that Cur-ns could be more easily engulfed into RAW264.7 cells than free Cur and accumulated more under the stimulation of the ultrasound. Reactive oxygen species (ROS) inside RAW264.7 cells after SDT led to the decrease of mitochondrial membrane potential (MMP) and the higher expression of cleaved caspase-9/3. The results of in vivo experiments showed that Cur-ns-SDT reduced the level of total cholesterol (TC) and low density lipoprotein (LDL) and promoted the transformation from M1 to M2 macrophages, relieved atherosclerosis syndrome. Therefore, Cur-ns-SDT was a potential treatment of anti-atherosclerosis by enhancing macrophages apoptosis through mitochondrial pathway and inhibiting the progression of plaques by interfering with macrophages polarization.


Assuntos
Aterosclerose/terapia , Curcumina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanomedicina Teranóstica/métodos , Terapia por Ultrassom/métodos , Administração Oral , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Aterosclerose/sangue , Disponibilidade Biológica , Colesterol/sangue , Terapia Combinada/métodos , Curcumina/farmacocinética , Modelos Animais de Doenças , Humanos , Lipoproteínas LDL/sangue , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos da radiação , Camundongos , Camundongos Knockout para ApoE , Nanopartículas/química , Tamanho da Partícula , Veículos Farmacêuticos/química , Povidona/química , Células RAW 264.7 , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/efeitos da radiação , Dodecilsulfato de Sódio/química
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