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1.
J Photochem Photobiol B ; 201: 111653, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31710929

RESUMO

Autophagy is an important process for maintaining intracellular homeostasis. Our previous study demonstrated that autophagy was down-regulated in ultraviolet B (UVB)-irradiated keratinocytes. Raffinose is a natural oligosaccharide that serves as a novel activator of autophagy and as a balancing agent to regulate the diversity of environmental stress. However, whether raffinose balances ultraviolet stress through the autophagy activation pathway has yet to be established. In this study, we found that raffinose treatment inhibited the LDH release and trypan blue staining in UVB-challenged human keratinocytes cell line HaCaT but did not affect the cleavage of apoptotic markers Caspase-3 and PARP, as well as translocation into nucleus of other cell death markers Endonuclease G and AIF. Moreover, we confirmed that raffinose treatment enhanced autophagy flux in an MTOR-independent manner in HaCaT cells. Importantly, decrease of LC3-II turnover in UVB-irradiated keratinocytes could be rescued by raffinose treatment, indicating that raffinose treatment increased autophagy in UVB-irradiated HaCaT cells. Furthermore, the effect on cell death by raffinose was inhibited when autophagy was suppressed with either a small interfering RNA targeting ATG5 (siATG5) or autophagic inhibitor wortmannin. In conclusion, we demonstrated that raffinose increases MTOR-independent autophagy and reduces cell death in UVB-irradiated keratinocytes. Our study indicated that the natural agent raffinose presents the potential value in opposing photodamage.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Rafinose/farmacologia , Raios Ultravioleta , Apoptose/efeitos da radiação , Autofagia/efeitos da radiação , Proteína 5 Relacionada à Autofagia/antagonistas & inibidores , Proteína 5 Relacionada à Autofagia/genética , Proteína 5 Relacionada à Autofagia/metabolismo , Caspase 3/metabolismo , Linhagem Celular , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo
3.
J Exp Clin Cancer Res ; 38(1): 325, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31331356

RESUMO

BACKGROUND: Sodium/iodide symporter (NIS)-mediated iodide uptake plays an important physiological role in regulating thyroid gland function, as well as in diagnosing and treating Graves' disease and thyroid cancer. High-mobility group box 1 (HMGB1), a highly conserved nuclear protein, is a positive regulator of autophagy conferring resistance to chemotherapy, radiotherapy and immunotherapy in cancer cells. Here the authors intended to identify the role of HMGB1 in Hank's balanced salt solution (HBSS)-induced autophagy, explore NIS protein degradation through a autophagy-lysosome pathway in thyroid cancer cells and elucidate the possible molecular mechanisms. METHODS: Immunohistochemical staining and reverse transcription-polymerase chain reaction (RT-PCR) were performed for detecting the expression of HMGB1 in different tissues. HMGB1 was knocked down by lentiviral transfection in FTC-133/TPC-1 cells. Autophagic markers LC3-II, p62, Beclin1 and autophagosomal formation were employed for evaluating HMGB1-mediated autophagy in HBSS-treated cells by Western blot, immunofluorescence and electron microscopy. Western blot, quantitative RT-PCR and gamma counter analysis were performed for detecting NIS expression and iodide uptake in HMGB1-knockdown cells after different treatments. The reactive oxygen species (ROS) level, ROS-mediated LC3-II expression and HMGB1 cytosolic translocation were detected by fluorospectrophotometer, flow cytometry, Western blot and immunofluorescence. HMGB1-mediated AMPK, mTOR and p70S6K phosphorylation (p-AMPK, p-mTOR & p-p70S6K) were detected by Western blot. Furthermore, a nude murine model with transplanted tumor was employed for examining the effect of HMGB1-mediated autophagy on imaging and biodistribution of 99mTcO4-. NIS, Beclin1, p-AMPK and p-mTOR were detected by immunohistochemical staining and Western blot in transplanted tumor samples. RESULTS: HMGB1 was a critical regulator of autophagy-mediated NIS degradation in HBSS-treated FTC-133/TPC-1 cells. And HMGB1 up-regulation was rather prevalent in thyroid cancer tissues and closely correlated with worse overall lymph node metastasis and clinical stage. HMGB1-knockdown dramatically suppressed autophagy, NIS degradation and boosted iodide uptake in HBSS-treated cells. Moreover, HBSS enhanced ROS-sustained autophagy and promoted the cytosolic translocation of HMGB1. A knockdown of HMGB1 suppressed LC3-II conversion and NIS degradation via an AMPK/mTOR-dependent signal pathway through a regulation of ROS generation, rather than ATP. Furthermore, these data were further supported by our in vivo experiment of xenografts formed by HMGB1 knockdown cells reverting the uptake of 99mTcO4- as compared with control shRNA-transfected cells in hunger group. CONCLUSIONS: Acting as a critical regulator of autophagy-mediated NIS degradation via ROS/AMPK/mTOR pathway, HMGB1is a potential intervention target of radioiodine therapy in thyroid cancer.


Assuntos
Autofagia/genética , Proteína HMGB1/genética , Radioisótopos do Iodo/farmacologia , Simportadores/genética , Neoplasias da Glândula Tireoide/radioterapia , Animais , Autofagossomos/efeitos dos fármacos , Autofagia/efeitos da radiação , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Técnicas de Silenciamento de Genes , Xenoenxertos , Humanos , Radioisótopos do Iodo/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteólise/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Simportadores/química , Glândula Tireoide/efeitos da radiação , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia
4.
Cell Physiol Biochem ; 53(1): 242-257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31313540

RESUMO

BACKGROUND/AIMS: Excessive exposure to UV radiation negatively affects the human skin, characterized by photo-damage (premature aging & carcinogenesis). UV-B radiation causes about 90% of non-melanoma skin cancers by damaging de-oxy ribonucleic acids (DNA). We have previously reported that UV-B radiation induces skin photodamage through oxidative & Endoplasmic Reticulum (ER) stresses and Glycyrrhizic acid (GA), a natural triterpene, protects skin cells against such stresses. UV-B radiation elicits signalling cascade by activation of proteins involved in sensing, signalling, and repair process of DNA damage. In this study, we explored the effects & mechanisms of Glycyrrhizic acid (GA) against UV-B -induced photodamage using a well established cellular model. METHODS: We used primary human dermal fibroblasts as a cellular model. The cells were cultured in the presence or absence of GA for 3,6, & 24 h. Effect of UV-B was assessed by examining cell viability, cell morphology, oxidative stress, ER stress, DNA damage & cellular autophagy levels through biochemical assays, microscopy & protein expression studies. RESULTS: In this study, we have determined the effect of GA on autophagy mediated DNA damage response system as the main mechanism in preventing photodamage due to UV-B -irradiation to primary human dermal fibroblasts (HDFs). GA treatment to UV-B exposed HDFs, significantly inhibited cell death, oxidative & ER stress responses, prevented Cyclobutane Pyrimidine dimer (CPD) DNA adduct formation, and DNA fragmentation via modulation of UV-B induced autophagic flux. Present results showed that GA treatment quenched reactive oxygen species (ROS), relieved ER stress response, improved autophagy (6 hr's post-UV-B -irradiation) and prevented UV-B induced DNA damage. CONCLUSION: The present study links autophagy induction by GA as the main mechanism in the prevention of DNA damage and provides a mechanistic basis for the photoprotective effect of GA and suggests that GA can be potentially developed as a promising agent against UV-B induced skin photo-damage.


Assuntos
Autofagia , Derme/metabolismo , Fibroblastos/metabolismo , Ácido Glicirrízico/farmacologia , Estresse Oxidativo , Raios Ultravioleta/efeitos adversos , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Células Cultivadas , Derme/patologia , Fibroblastos/patologia , Humanos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação
5.
Photodermatol Photoimmunol Photomed ; 35(5): 360-368, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31166622

RESUMO

BACKGROUND/PURPOSE: Ultraviolet (UV) A (315-400 nm) is the UV light that most frequently reaches the Earth's surface and can penetrate the epidermis through to the dermis, causing various issues, including skin aging and skin cancer. The results of our previous studies have shown that the flavonoid monomer cyanidin-3-o-glucoside (C3G) can effectively inhibit primary human dermal fibroblast (HDF) oxidative damage and apoptosis caused by UVA radiation. Many flavonoids can regulate the level of autophagy. However, whether C3G inhibits UVA-induced oxidative damage to primary HDFs by regulating autophagy levels remains unclear. METHODS AND RESULTS: In this study, we used different doses (0-12 J/cm2 ) of UVA to irradiate cells and showed that the expression levels of autophagy-related gene 5 (Atg5) and microtubule-associated protein 1 light chain 3 (LC3)-II in primary HDFs first increased and then decreased. The expression of Atg5 and LC3-II was significantly decreased under 12 J/cm2 (light-damage model). C3G increased the levels of Atg5 and LC3-II. Primary HDFs were pretreated with C3G, followed by treatment with the autophagy inhibitor 3-methyladenine (3-MA) after 12 J/cm2 UVA irradiation. The inhibitory effects of C3G on morphological changes, oxidative damage, and apoptosis in primary HDFs induced by UVA were significantly decreased. CONCLUSION: C3G can inhibit UVA-induced damage to primary HDFs by inducing autophagy. These results provide a theoretical basis for the application of natural compounds to resist light damage to the skin in the future.


Assuntos
Antocianinas/farmacologia , Autofagia , Derme/metabolismo , Fibroblastos/metabolismo , Glucosídeos/farmacologia , Raios Ultravioleta/efeitos adversos , Regulação para Cima , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Células Cultivadas , Derme/patologia , Fibroblastos/patologia , Humanos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/efeitos da radiação
6.
Oncol Rep ; 42(1): 377-385, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059051

RESUMO

The PI3K/AKT/mTOR pathway and autophagy are known to play important roles in cancer radioresistance. The aim of the present study was to investigate whether the combination of temsirolimus (TEM), an mTOR inhibitor, and chloroquine (CQ), an autophagy inhibitor, can increase radiosensitivity in colorectal cancer (CRC) cells. The efficacies of TEM and/or CQ as radiosensitizers were examined using clonogenic assays in CRC cell lines SW480 and HT­29. The expression levels of the phosphorylated isoforms of S6 and 4E­BP1, downstream proteins of mTOR, as well as the expression levels of p62 and LC3, autophagy­related proteins, were assessed by western blot analysis. The formation of acidic organelles was detected in acridine orange­stained cells. Apoptosis and caspase activity were assessed using flow cytometry. The results revealed that ionizing radiation (IR) activated the downstream proteins of mTOR and induced autophagy. In the clonogenic assays, neither TEM nor CQ influenced the efficacy of IR, whereas their combination significantly increased the dose­dependent efficacy of IR. TEM inhibited phosphorylation of the downstream proteins of mTOR and induced autophagy. CQ inhibited autophagy in the late phase and did not influence the downstream proteins of mTOR. TEM and CQ inhibited both the phosphorylation of downstream proteins of mTOR and autophagy. Cell death analysis revealed that the combination of TEM and CQ strongly induced apoptosis in cells exposed to IR. In conclusion, the combination of TEM and CQ increased radiosensitivity in CRC cells through co­inhibition of mTOR and autophagy.


Assuntos
Autofagia/efeitos dos fármacos , Cloroquina/farmacologia , Neoplasias Colorretais/metabolismo , Radiossensibilizantes/farmacologia , Sirolimo/análogos & derivados , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Autofagia/efeitos da radiação , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Neoplasias Colorretais/terapia , Células HT29 , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Proteínas de Ligação a RNA/metabolismo , Proteínas Quinases S6 Ribossômicas/metabolismo , Sirolimo/farmacologia
7.
Oxid Med Cell Longev ; 2019: 9679731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31073356

RESUMO

Ethnopharmacological Relevance. Penthorum chinense Pursh (Penthoraceae) is a traditional herbal plant that has been used in China for the treatment of jaundice, cholecystitis, edema, and infectious hepatitis. In addition, the Korea Medicinal Plant Dictionary states that Penthorum chinense Pursh can be used to treat contusions and skin bruises by improving blood flow. Recent studies have shown that Penthorum chinense Pursh ethanol extract (Pc-EE) exhibits strong antioxidant effects. In this study, we examined the effects of Pc-EE on UVB-induced or H2O2-induced oxidative stress, as well as its antimelanogenic properties. Cell viability, matrix metalloproteinase (MMP) expression, cyclooxygenease-2 (COX-2), and interleukin-6 (IL-6) expression and moisturizing factors were investigated in keratinocytes. Collagen synthesis induction was measured in HEK293T cells. For melanogenesis, the effects of Pc-EE on melanin content and tyrosinase activity were measured. Additionally, the antimelanogenic- and autophagy-inducing activities of Pc-EE were examined using immunoblotting and confocal microscopy. Pc-EE protected HaCaT cells against death from UVB irradiation- or H2O2-induced oxidative stress. Pc-EE increased the promoter activity of the type 1 procollagen gene Col1A1 and decreased the expression of MMPs, COX-2, IL-6, and hyaluronidase induced by UVB irradiation- or H2O2-induced oxidative stress. Pc-EE showed a strong antioxidant effect in the DPPH assay. In α-melanocyte-stimulating hormone- (α-MSH-) stimulated B16F10 cells, Pc-EE reduced melanin production, decreased tyrosinase expression and microphthalmia-associated transcription factor (MITF) protein levels, and decreased the phosphorylation levels of p38 and JNK. In HEK293T cells, Pc-EE promoted the expression of GFP-LC3B. In B16F10 cells, the LC3B and melanin contents were reduced by Pc-EE and were restored by the autophagy inhibitor 3-methyladenine (3-MA). These results suggest that Pc-EE can be used as a skin protection agent due to its antiapoptotic, antiaging, anti-inflammatory, and antimelanogenic properties.


Assuntos
Antioxidantes/farmacologia , Autofagia/efeitos dos fármacos , Etanol/química , Melaninas/antagonistas & inibidores , Extratos Vegetais/farmacologia , Saxifragaceae/química , Envelhecimento da Pele/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Autofagia/efeitos da radiação , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Colágeno/metabolismo , Humanos , Peróxido de Hidrogênio/toxicidade , Inflamação/patologia , Melanoma Experimental/patologia , Camundongos , Oxirredução , Transdução de Sinais/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta , alfa-MSH/farmacologia
8.
Oncol Rep ; 41(5): 3100-3110, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30976815

RESUMO

The pleiotropic effects of hyperthermia on cancer cells have been well documented, and microwave hyperthermia (MWHT) has been widely applied for multifarious cancer treatment. However, the mechanisms underlying the anticancer effect of MWHT combined with gemcitabine (GEM) remain poorly understood. The aim of the present study was to investigate the role of autophagy in the thermo­chemotherapy of human squamous cell lung carcinoma cells. It was observed that MWHT combined with GEM potently suppressed the viability of NCI­H2170 and NCI­H1703 cells, and induced G0/G1 cell cycle arrest. Notably, MWHT with GEM induced autophagy, as indicated by the formation of autophagic vacuoles, downregulation of p62 and upregulation of light chain 3­II. It was further demonstrated that the autophagy was due to the production of reactive oxygen species (ROS), whereas N­acetyl cysteine, an ROS scavenger, attenuated the level of autophagy. However, when the autophagy inhibitor 3­methyladenine was used, there was no significant change in the production of ROS. Furthermore, it was observed that MWHT combined with GEM downregulated the protein expression levels of phosphoinositide 3­kinase (PI3K), phosphorylated (p)­PI3K, protein kinase B (AKT), p­AKT, mammalian target of rapamycin (mTOR), p­mTOR, phosphorylated S6 (pS6) and p70 S6 kinase, which are associated with autophagy. In addition, the results demonstrated that ROS served as an upstream mediator of PI3K/AKT/mTOR signaling. In light of these findings, the present study provides original insights into the molecular mechanisms underlying the cell death induced by MWHT combined with GEM, and this may be a promising approach for the treatment of human squamous cell lung carcinoma.


Assuntos
Autofagia/efeitos da radiação , Carcinoma Pulmonar de Células não Pequenas/terapia , Desoxicitidina/análogos & derivados , Hipertermia Induzida/métodos , Neoplasias Pulmonares/terapia , Adenina/análogos & derivados , Adenina/farmacologia , Autofagia/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Terapia Combinada/métodos , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos da radiação , Humanos , Neoplasias Pulmonares/patologia , Micro-Ondas/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Serina-Treonina Quinases TOR/metabolismo
9.
BMB Rep ; 52(4): 277-282, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30940322

RESUMO

Currently speaking, it is noted that radiofrequency ablation (RFA) has been the most widely used treatment for hepatocellular carcinoma (HCC) occurring in patients. However, accumulating evidence has demonstrated that the incidence of insufficient RFA (IRFA) may result in the identified rapid progression of residual HCC in the patient, which can greatly hinder the effectiveness and patient reported benefits of utilizing this technique. Although many efforts have been proposed, the underlying mechanisms triggering the rapid progression of residual HCC after IRFA have not yet been fully clarified through current research literature reviews. It was shown in this study that cell proliferation, migration and invasion of residual HepG2 and SMMC7721 cells were significantly increased after the IRFA was simulated in vitro. In other words, it is noted that IRFA could do this by enhancing the image of autophagy of the residual HCC cell via the HIF-1α/BNIP3 pathway. Consequently, the down-regulation of BNIP3 may result in the inhibition of the residual HCC cell progression and autophagy after IRFA. Our present study results suggest that IRFA could promote residual HCC cell progression in vitro by enhancing autophagy via the HIF-1α/BNIP3 pathway. For this reason, it is noted that the targeting of the BNIP3 may be useful in preventing the rapid growth and metastasis of residual HCC after IRFA. [BMB Reports 2019; 52(4): 277-282].


Assuntos
Carcinoma Hepatocelular/terapia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias Hepáticas/terapia , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ablação por Radiofrequência/métodos , Autofagia/efeitos da radiação , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Progressão da Doença , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Ablação por Radiofrequência/tendências , Transdução de Sinais
10.
J Photochem Photobiol B ; 194: 84-95, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30933875

RESUMO

Ultraviolet (UV)-B radiation is a major environmental risk factor that is responsible for the development and progression of many skin cancers. Apigenin, a type of bioflavonoid, has been reported to inhibit UVB-induced skin cancer. However, how apigenin functions in keratinocytes with UV damage remains unclear. In this study, by lactate dehydrogenase (LDH) release assay, we found that apigenin treatment increased cell death in the primary human epidermal keratinocytes (HEKs) and the cutaneous squamous cell carcinoma cell line COLO-16. Apigenin treatment reduced microtubule-associated protein 1 light chain 3 (LC3)-II turnover, acridine orange staining and GFP-LC3 puncta in both cell types, suggesting autophagy inhibition. However, apigenin treatment restored the inhibition of autophagy in UVB-challenged HEKs. Moreover, apigenin treatment restored the UVB-induced downregulation of ataxia-telangiectasia mutated (ATM), ataxia-telangiectasia, Rad3-related (ATR) and the unfolded protein response (UPR) regulatory proteins, BiP, IRE1α and PERK in HEKs. Apigenin treatment also inhibited UVB-induced apoptosis and cell death in HEKs. In addition, autophagy inhibition by autophagy-related gene (ATG) 5 RNA interference interrupted apigenin-induced restoration of ATR, ATM and BiP, which were downregulated in HEKs exposed to UVB radiation. Our findings indicate that apigenin exhibits a novel protective effect in keratinocytes with UVB damage, suggesting potential application as a photoprotective agent.


Assuntos
Apigenina/farmacologia , Autofagia/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Autofagia/efeitos da radiação , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Regulação para Baixo/efeitos da radiação , Células HEK293 , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Protetores contra Radiação/farmacologia , Resposta a Proteínas não Dobradas/efeitos da radiação
11.
J Photochem Photobiol B ; 194: 46-55, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30925276

RESUMO

Human papillomavirus (HPV) infection is linked to several diseases, the most prominent of which are cervical cancer and genital condyloma acuminatum. Previous studies have suggested an effective role for 5-aminolevulinic acid photodynamic therapy (ALA-PDT) against various cancers by the induction of autophagy and apoptosis. However, few reports have focused on the effectiveness of ALA-PDT on HPV related disorders. To identify the role of ALA-PDT in the context of HPV infection, we initially investigated 111 patients suffering from genital condyloma acuminatum. HPV viral load detected before and after ALA-PDT treatment was compared during this procedure; a significant difference was noted. HeLa (HPV18) cells were exposed to ALA-PDT in vitro to further explore the underlying mechanisms. Western blot analysis showed that ALA-PDT induces LC3II and p62 expression, along with the up regulation of caspase-3 and cleaved caspase-3. Our study also demonstrated that ALA-PDT treatment inhibits the proliferation of HeLa cells in a dose dependent manner and effectively reduces HPV viral load via autophagy and apoptosis by regulating the Ras/Raf/MEK/ERK and PI3K/AKT/mTOR pathways. Hydroxychloroquine (HCQ), although it inhibited autophagy degradation, functioned to activate reactive oxygen species (ROS) levels of ALA-PDT to enhance the observed effect. These findings suggest strategies for the improvement of PDT efficacy in patients.


Assuntos
Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Ácidos Levulínicos/farmacologia , Papillomaviridae/fisiologia , Fotoquimioterapia , Carga Viral/efeitos dos fármacos , Carga Viral/efeitos da radiação , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HeLa , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos da radiação , Papillomaviridae/efeitos dos fármacos , Papillomaviridae/efeitos da radiação , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Quinases raf/metabolismo , Proteínas ras/metabolismo
12.
J Photochem Photobiol B ; 194: 32-45, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30904584

RESUMO

Sun or therapy-related ultraviolet B (UVB) irradiation induces different cell death modalities such as apoptosis, necrosis/necroptosis and autophagy. Understanding of mechanisms implicated in regulation and execution of cell death program is imperative for prevention and treatment of skin diseases. An essential component of death-inducing complex is Fas-associated protein with death domain (FADD), involved in conduction of death signals of different death modalities. The purpose of this study was to enlighten the role of FADD in the selection of cell death mode after narrow-band UVB (NB-UVB) irradiation using specific cell death inhibitors (carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (zVAD-fmk), Necrostatin-1 and 3-Methyladenine) and FADD-deficient (FADD-/-) mouse embryonic fibroblasts (MEFs) and their wild type (wt) counterparts. The results imply that lack of FADD sensitized MEFs to induction of receptor-interacting protein 1 (RIPK1)-dependent apoptosis by the generation of reactive oxygen species (ROS), but without activation of the proteins p53, Bax and Bcl-2 as well as without the enrolment of calpain-2. Autophagy was established as a contributing factor to NB-UVB-induced death execution. By contrast, wt cells triggered intrinsic apoptotic pathway that was resistant to the inhibition by zVAD-fmk and Necrostatin-1 pointing to the mechanism overcoming the cell survival. These findings support the role of FADD in prevention of autophagy-dependent apoptosis.


Assuntos
Apoptose/efeitos da radiação , Autofagia/efeitos da radiação , Proteína de Domínio de Morte Associada a Fas/deficiência , Fibroblastos/citologia , Fibroblastos/efeitos da radiação , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Raios Ultravioleta , Clorometilcetonas de Aminoácidos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Dano ao DNA , Embrião de Mamíferos/citologia , Fibroblastos/metabolismo , Imidazóis/farmacologia , Indóis/farmacologia , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
13.
Photochem Photobiol Sci ; 18(2): 546-554, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30681107

RESUMO

Photodynamic therapy (PDT) is a clinically approved treatment that exerts a selective cytotoxic activity toward cancer cells. The procedure involves the administration of a photosensitizer drug followed by its activation by visible light. In the presence of oxygen, a series of events lead to tumor cell death. PDT releases different cell signals, some of these lead to death while others can lead to survival. The surviving or resistant cells contribute to the recurrence of tumors after treatment, from which the necessity to understand this molecular response induced by PDT arises. It has been shown that both Heat Shock Proteins (HSPs) and autophagy promote PDT resistance. Moreover, both of them can be stimulated by PDT treatment. However, the molecular interplay between HSPs and autophagy in the photodynamic therapy context is poorly understood. We studied whether PDT induces autophagic activity through HSPs. We demonstrated that PDT promoted HSP27 expression, which in turn triggered autophagic cell survival as well as inhibited apoptosis in colon cancer cells. In addition, an overexpression of the HSP27/autophagy axis was observed in skin carcinoma cells resistant to PDT.


Assuntos
Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Proteínas de Choque Térmico HSP27/metabolismo , Fotoquimioterapia , Células CACO-2 , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Técnicas de Silenciamento de Genes , Proteínas de Choque Térmico HSP27/deficiência , Proteínas de Choque Térmico HSP27/genética , Humanos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia
14.
Artif Cells Nanomed Biotechnol ; 47(1): 132-143, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30663430

RESUMO

Glioblastoma is a heterogeneous disease with multiple genotypic origins. Despite treatment protocols such as surgery, radiotherapy and chemotherapy, the prognosis for patients remains poor. This study investigates the cytotoxic and radiation dose-enhancing and radiosensitizing ability of five rare earth oxide nanoparticles, in two different immortalized mammalian cell lines; U-87 MG and Mo59K. Significant cytotoxicity was observed in U-87 MG cells when exposed to Nd2O3 and La2O3. Autophagy was also detected in cells after incubation with Nd2O3. Radiosensitization was observed in U-87 MG when incubated with Gd2O3, CeO2-Gd and Nd2O3:Si. Importantly, these elements did not cause any intrinsic toxicity in the absence of irradiation and so could be considered biocompatible. The Gd2O3 and CeO2-Gd nanoparticles were also seen to generate ROS in U-87 MG cells after irradiation. Furthermore, the Mo59K and U-87 MG cells responded very differently to exposure to the rare earth nanoparticles. This may indicate the importance of the genotype of cells in the successful use of rare earth oxides for treatment.


Assuntos
Glioblastoma/patologia , Nanopartículas Metálicas/química , Metais Terras Raras/química , Metais Terras Raras/farmacologia , Radiossensibilizantes/química , Radiossensibilizantes/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Neoplasias Encefálicas/patologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta a Droga , Humanos , Espécies Reativas de Oxigênio/metabolismo
15.
J Radiat Res ; 60(2): 163-170, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30624744

RESUMO

Radiation-induced rescue effect (RIRE) refers to the phenomenon in which detrimental effects in targeted irradiated cells are reduced upon receiving feedback signals from partnered non-irradiated bystander cells, or from the medium previously conditioning these partnered non-irradiated bystander cells. For convenience, in the current review we define two types of RIRE: (i) Type 1 RIRE (reduced detrimental effects in targeted cells upon receiving feedback signals from bystander cells) and (ii) Type 2 RIRE (exacerbated detrimental effects in targeted cells upon receiving feedback signals from bystander cells). The two types of RIRE, as well as the associated mechanisms and chemical messengers, have been separately reviewed. The recent report on the potential effects of RIRE on the traditional colony-formation assays has also been reviewed. Finally, future priorities and directions for research into RIRE are discussed.


Assuntos
Efeito Espectador/efeitos da radiação , Radiação , Animais , Autofagia/efeitos da radiação , Ensaio de Unidades Formadoras de Colônias , Humanos , NF-kappa B/metabolismo , Transdução de Sinais
16.
Aquat Toxicol ; 208: 20-28, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30597291

RESUMO

This study aimed to elucidate the biological responses of eelgrass (Zostera marina) to artificially induced stresses such as herbicide (Irgarol 1051, Irg) exposure, insufficient light, and high water temperature (27 ± 1.0 °C) by evaluating growth inhibition, photosynthetic activity, and metabolomic profiles. After 14 days, all treatments inhibited growth, but photosynthetic activity was only reduced in the Irg-exposed group. In the Irg-exposed and insufficient light groups, the metabolomic profiles were characterized by decreased levels of sugar (sucrose) and increased levels of amino acids such as glutamine, glycine, and leucine. Biochemical and ultrastructural analyses revealed that the loss of sugar-derived metabolic energy was compensated for by energy generated during autophagic protein degradation. Furthermore, the level of myo-inositol, which has various biological roles and participates in several cellular processes such as cell wall synthesis, stress response, and mineral nutrient storage, was markedly increased in the Irg-exposed and insufficient light groups. A combination of metabolomic analysis with other analyses such as measurement of photosynthetic activity might further elucidate the response of eelgrass to ambient stresses in the natural environment.


Assuntos
Herbicidas/toxicidade , Temperatura Alta , Luz , Água/química , Zosteraceae/fisiologia , Zosteraceae/efeitos da radiação , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Metaboloma/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Análise de Componente Principal , Triazinas/toxicidade , Poluentes Químicos da Água/toxicidade , Zosteraceae/efeitos dos fármacos , Zosteraceae/crescimento & desenvolvimento
17.
Cerebellum ; 18(1): 22-32, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29725949

RESUMO

Spinocerebellar ataxia type 3 (SCA3) is a polyglutamine neurodegenerative disease resulting from the misfolding and accumulation of a pathogenic protein, causing cerebellar dysfunction, and this disease currently has no effective treatments. Far-infrared radiation (FIR) has been found to protect the viability of SCA3 cells by preventing mutant ataxin-3 protein aggregation and promoting autophagy. However, this possible treatment still lacks in vivo evidence. This study assessed the effect of FIR therapy on SCA3 in vivo by using a mouse model over 28 weeks. Control mice carried a healthy wild-type ATXN3 allele that had a polyglutamine tract with 15 CAG repeats (15Q), whereas SCA3 transgenic mice possessed an allele with a pathological polyglutamine tract with expanded 84 CAG (84Q) repeats. The results showed that the 84Q SCA3 mice displayed impaired motor coordination, balance abilities, and gait performance, along with the associated loss of Purkinje cells in the cerebellum, compared with the normal 15Q controls; nevertheless, FIR treatment was sufficient to prevent those defects. FIR significantly improved performance in terms of maximal contact area, stride length, and base support in the forepaws, hindpaws, or both. Moreover, FIR treatment supported the survival of Purkinje cells in the cerebellum and promoted the autophagy, as reflected by the induction of autophagic markers, LC3II and Beclin-1, concomitant with the reduction of p62 and ataxin-3 accumulation in cerebellar Purkinje cells, which might partially contribute to the rescue mechanism. In summary, our results reveal that FIR confers therapeutic effects in an SCA3 transgenic animal model and therefore has considerable potential for future clinical use.


Assuntos
Cerebelo/patologia , Raios Infravermelhos/uso terapêutico , Doença de Machado-Joseph/patologia , Doença de Machado-Joseph/radioterapia , Atividade Motora , Animais , Ataxina-3/genética , Ataxina-3/metabolismo , Autofagia/efeitos da radiação , Cerebelo/metabolismo , Cerebelo/efeitos da radiação , Modelos Animais de Doenças , Marcha/efeitos da radiação , Doença de Machado-Joseph/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Atividade Motora/efeitos da radiação , Equilíbrio Postural/efeitos da radiação , Distribuição Aleatória
18.
Cell Mol Life Sci ; 76(7): 1255-1273, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30535789

RESUMO

This article reviews the current knowledge on the mechanisms of adaptive response to low doses of ionizing radiation or chemical exposure. A better knowledge of these mechanisms is needed to improve our understanding of health risks at low levels of environmental or occupational exposure and their involvement in cancer or non-cancer diseases. This response is orchestrated through a multifaceted cellular program involving the concerted action of diverse stress response pathways. These evolutionary highly conserved defense mechanisms determine the cellular response to chemical and physical aggression. They include DNA damage repair (p53, ATM, PARP pathways), antioxidant response (Nrf2 pathway), immune/inflammatory response (NF-κB pathway), cell survival/death pathway (apoptosis), endoplasmic response to stress (UPR response), and other cytoprotective processes including autophagy, cell cycle regulation, and the unfolded protein response. The coordinated action of these processes induced by low-dose radiation or chemicals produces biological effects that are currently estimated with the linear non-threshold model. These effects are controversial. They are difficult to detect because of their low magnitude, the scarcity of events in humans, and the difficulty of corroborating associations over the long term. Improving our understanding of these biological consequences should help humans and their environment by enabling better risk estimates, the revision of radiation protection standards, and possible therapeutic advances.


Assuntos
Poluentes Ambientais/toxicidade , Radiação Ionizante , Transdução de Sinais/efeitos dos fármacos , Antioxidantes/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Poluentes Ambientais/química , Humanos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transdução de Sinais/efeitos da radiação , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Resposta a Proteínas não Dobradas/efeitos da radiação
19.
Int J Biochem Cell Biol ; 111: 12-18, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30278227

RESUMO

Treatment failure through radioresistance of tumors is associated with activation of the epidermal growth factor receptor (EGFR). Tumor cell proliferation, DNA-repair, hypoxia and metastases-formation are four mechanisms in which EGFR signaling has an important role. However, the effect of hypoxia on EGFR expression is still controversial. In this study, we demonstrated that hypoxia enhanced EGFR expression and sustained cell survival in SiHa, CAL 27 and A549 cells at both low and high cell desnities, while in MCF-7, MDA-MB-231 and HeLa cells, EGFR and cell survival were regulated by hypoxic treatment in a cell-density dependent manner: upregulated at low cell density and downregulated at high cell density. In MCF-7 and HeLa xenografts in nude mice, EGFR expression varied inversely with the pimonidazole level that was used as an indicator of hypoxia, accordant with the effect of hypoxia at high cell density in vitro. Hypoxia induced more remarkable cell autophagy at high cell density than at low cell density. Autophagy inhibitor 3MA, rather than proteasome inhibitor MG132 inhibited hypoxia-mediated EGFR loss and shifted cell death to cell survival in HeLa cells. The MCF7 cells' sensitivity to ionizing radiation (IR) under hypoxia was also conditional on the cell densities when the hypoxia treatment was introduced, inversely associated with the expression levels of EGFR. Altogether, hypoxia can decrease EGFR expression in some cell lines by enhancing autophagy at high cell density, leading to cell death and hypersensitivity to radiotherapy. This study may help to understand how hypoxia influences EGFR expression and radiosensitivity.


Assuntos
Autofagia/efeitos da radiação , Receptores ErbB/metabolismo , Tolerância a Radiação , Hipóxia Tumoral/efeitos da radiação , Animais , Contagem de Células , Proliferação de Células/efeitos da radiação , Transformação Celular Neoplásica , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Células HeLa , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos BALB C
20.
Biomed Pharmacother ; 111: 282-291, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30590316

RESUMO

Ultraviolet light (UV) is a major inducer of skin cancer. Therefore, recovery and removal of UV-damaged skin cells are important in the prevention of skin carcinogenesis. Here, we investigated the effect of deep sea water (DSW) in HaCaT keratinocyte exposed by UVB (λ = 290∼320 nm). The result showed that UVB-induced cell death was reinforced by DSW treatment in a hardness-dependent manner. Furthermore, the increase of cell death by DSW was associated with the down-regulation of survivin and RAD51 expressions induced by UVB. Moreover, we confirmed the inhibition of H2 A.X phosphorylation, a marker for double-stranded DNA damage, and the enhancement of LC3-II and SQSTM1/p62 expressions by DSW administration in UVB-radiated HaCaT keratinocyte. The results imply that the enhancement of UVB-induced cell death by DSW is associated with autophagy. Therefore, we further explored the regulation of autophagy-regulating proteins and apoptosis-related factors expression. Phosphorylation of mammalian target of rapamycin (mTOR), ribosomal protein S6, and S6 kinase by UVB radiation were regressed via DSW treatment, underlying the increase of AMP-activated protein kinase (AMPK) phosphorylation. Furthermore, UVB-enhanced nuclear factor κB (NF-κB) and c-Jun N-terminal kinase (JNK) phosphorylations were increased with DSW treatment. Contrastingly, DSW lessened the Ser15 phosphorylation of p53 and cleavage of poly (ADP-ribose) polymerase induced by UVB radiation. Consequently, the results demonstrate that DSW enhances UVB-damaged skin cell clearance through the activation of autophagic cell death underlying the regulation of AMP-activated protein kinase (AMPK)/mTOR signaling as well as NF-κB and JNK phosphorylations. In conclusion, this investigation suggests that DSW is a potent candidate for the prevention of UV-induced skin cancer development.


Assuntos
Autofagia/efeitos da radiação , Carcinogênese/efeitos da radiação , Queratinócitos/efeitos da radiação , Água do Mar , Neoplasias Cutâneas/prevenção & controle , Raios Ultravioleta/efeitos adversos , Autofagia/fisiologia , Carcinogênese/patologia , Linhagem Celular , Sobrevivência Celular/fisiologia , Sobrevivência Celular/efeitos da radiação , Humanos , Queratinócitos/patologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/patologia
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