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1.
Nat Commun ; 11(1): 4907, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32999289

RESUMO

Global alterations in the metabolic network provide substances and energy to support tumor progression. To fuel these metabolic processes, extracellular matrix (ECM) plays a dominant role in supporting the mass transport and providing essential nutrients. Here, we report a fibrinogen and thrombin based coagulation system to construct an artificial ECM (aECM) for selectively cutting-off the tumor metabolic flux. Once a micro-wound is induced, a cascaded gelation of aECM can be triggered to besiege the tumor. Studies on cell behaviors and metabolomics reveal that aECM cuts off the mass transport and leads to a tumor specific starvation to inhibit tumor growth. In orthotopic and spontaneous murine tumor models, this physical barrier also hinders cancer cells from distant metastasis. The in vivo gelation provides an efficient approach to selectively alter the tumor mass transport. This strategy results in a 77% suppression of tumor growth. Most importantly, the gelation of aECM can be induced by clinical operations such as ultrasonic treatment, surgery or radiotherapy, implying this strategy is potential to be translated into a clinical combination regimen.


Assuntos
Materiais Biomiméticos/administração & dosagem , Matriz Extracelular/química , Neoplasias/terapia , Animais , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/efeitos da radiação , Materiais Biomiméticos/química , Materiais Biomiméticos/efeitos da radiação , Linhagem Celular Tumoral/transplante , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Quimiorradioterapia/métodos , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos da radiação , Feminino , Fibrinogênio/administração & dosagem , Fibrinogênio/química , Fibrinogênio/efeitos da radiação , Géis , Humanos , Injeções Intravenosas , Metabolômica , Camundongos , Neoplasias/metabolismo , Trombina/administração & dosagem , Trombina/química , Trombina/efeitos da radiação , Terapia por Ultrassom/métodos , Ondas Ultrassônicas
2.
Anticancer Res ; 40(9): 5001-5013, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32878788

RESUMO

AIM: Newly synthesized platinum(IV) complexes with ethylenediamine-N,N'-diacetate ligands (EDDA-type) (butyl-Pt and pentyl-Pt) were investigated against two cancer (A549 lung, and HTB 140 melanoma) and one non-cancerous (MRC-5 embryonic lung fibroblast) human cell lines. MATERIALS AND METHODS: The effects of these agents were compared with those of cisplatin after 6-, 24- and 48-h treatment. Sulforhodamine-B (SRB) assay was performed to estimate the cytotoxic effect, while the inhibitory effect on cell proliferation was measured using 5-bromo-2,-deoxyuridine (BrdU) incorporation assay. Cell cycle analysis was performed by flow cytometry. Type of cell death induced by these agents was determined by electrophoretic analysis of DNA, flow cytometry and by western blot analysis of proteins involved in induction of apoptosis. The effects of gamma irradiation, alone and in combination with platinum-based compounds, were examined by clonogenic and SRB assays. RESULTS: All examined platinum-based compounds had inhibitory and antiproliferative effects on A549 cells, but not on HTB140 and MRC-5 cells. Butyl-Pt, pentyl-Pt and cisplatin arrested the cell cycle in the S-phase and induced apoptotic cell death via regulation of expression of B-cell lymphoma 2 (BCL2) and BCL2-associated X (BAX) proteins. Platinum-based compounds increased the sensitivity of A549 cells to gamma irradiation. Butyl-Pt and pentyl-Pt showed better antitumour effects against A549 cells than did cisplatin, by interfering in cell proliferation and the cell cycle, and by triggering apoptosis. CONCLUSION: The effects of gamma irradiation on tumour cells may be amplified by pre-treatment of cells with platinum-based compounds.


Assuntos
Antineoplásicos/farmacologia , Compostos Organoplatínicos/farmacologia , Radiossensibilizantes/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , 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 , Cisplatino/farmacologia , Relação Dose-Resposta a Droga , Ácido Edético/análogos & derivados , Ácido Edético/química , Raios gama , Humanos , Concentração Inibidora 50 , Compostos Organoplatínicos/síntese química , Compostos Organoplatínicos/química , Radiossensibilizantes/síntese química , Radiossensibilizantes/química
3.
Nucleic Acids Res ; 48(18): 10342-10352, 2020 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-32894284

RESUMO

Ribosomal DNA (rDNA) consists of highly repeated sequences that are prone to incurring damage. Delays or failure of rDNA double-strand break (DSB) repair are deleterious, and can lead to rDNA transcriptional arrest, chromosomal translocations, genomic losses, and cell death. Here, we show that the zinc-finger transcription factor GLI1, a terminal effector of the Hedgehog (Hh) pathway, is required for the repair of rDNA DSBs. We found that GLI1 is activated in triple-negative breast cancer cells in response to ionizing radiation (IR) and localizes to rDNA sequences in response to both global DSBs generated by IR and site-specific DSBs in rDNA. Inhibiting GLI1 interferes with rDNA DSB repair and impacts RNA polymerase I activity and cell viability. Our findings tie Hh signaling to rDNA repair and this heretofore unknown function may be critically important in proliferating cancer cells.


Assuntos
DNA Ribossômico/genética , Proteínas Hedgehog/genética , RNA Polimerase I/genética , Neoplasias de Mama Triplo Negativas/radioterapia , Proteína GLI1 em Dedos de Zinco/genética , Proteínas de Ciclo Celular/genética , Nucléolo Celular/genética , Nucléolo Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Dano ao DNA/efeitos da radiação , Reparo do DNA/efeitos da radiação , DNA Ribossômico/efeitos da radiação , Regulação da Expressão Gênica/genética , Regulação da Expressão Gênica/efeitos da radiação , Humanos , RNA Polimerase I/efeitos da radiação , Radiação Ionizante , Ribossomos/genética , Ribossomos/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Transcrição Genética/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
4.
Mutat Res ; 856-857: 503220, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32928367

RESUMO

We assessed the radioprotective and mitigative actions of sodium diclofenac, a non-steroidal anti-inflammatory drug using cultured human peripheral blood as a model. Both pre- and post-irradiation treatments with the drug reduced gamma radiation-induced formation of dicentric chromosome, cytochalasin-blocked micronuclei and γ-H2AX foci in human peripheral blood lymphocytes. This work supports the concept that sodium diclofenac may be a useful radiation countermeasure agent.


Assuntos
Diclofenaco/farmacologia , Relação Dose-Resposta à Radiação , Histonas/genética , Protetores contra Radiação/farmacologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Aberrações Cromossômicas/efeitos dos fármacos , Aberrações Cromossômicas/efeitos da radiação , Análise Citogenética/métodos , Reposicionamento de Medicamentos , Raios gama/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Linfócitos/efeitos dos fármacos , Linfócitos/efeitos da radiação
5.
PLoS One ; 15(9): e0239456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32976517

RESUMO

The use of ultrasound-stimulated microbubble therapy has successfully been used to target tumor vasculature and enhance the effects of radiation therapy in tumor xenografts in mice. Here, we further investigate this treatment using larger, more clinically relevant tumor models. New Zealand white rabbits bearing prostate tumor (PC3) xenografts received a single treatment of either ultrasound-stimulated microbubbles (USMB), ionizing radiation (XRT; 8Gy), or a combination of both treatments (USMB+XRT). Treatment outcome was evaluated 24 hours after treatment using histopathology, immunolabeling, 3D Doppler ultrasound and photoacoustic imaging. A second cohort of rabbits received multiple treatments over a period of three weeks, where USMB treatments were delivered twice weekly with daily XRT treatments to deliver a fractionated 2Gy dose five days per week. A significant decrease in vascular function, observed through immunolabeling of vascular endothelial cells, was observed in tumors receiving the combined treatment (USMB+XRT) compared to control and single treatment groups. This was associated with an increase in cell death as observed through in situ end labeling (ISEL), a decrease in vascular index measured by Power Doppler imaging, and a decrease in oxygen saturation. In rabbits undergoing the long-term fractionated combined treatment, a significant growth delay was observed after 1 week and a significant reduction in tumor size was observed after 3 weeks with combined therapy. Results demonstrated an enhancement of radiation effect and superior anti-tumor effect of the combination of USMB+XRT compared to the single treatments alone. Tumor growth was maximally inhibited with fractionated radiotherapy combined with the ultrasound-stimulated microbubble-based therapy.


Assuntos
Microbolhas/uso terapêutico , Neoplasias da Próstata/radioterapia , Terapia por Ultrassom/métodos , Animais , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Terapia Combinada/métodos , Células Endoteliais/efeitos da radiação , Humanos , Masculino , Camundongos , Células PC-3 , Coelhos , Ondas Ultrassônicas
6.
PLoS Comput Biol ; 16(8): e1008041, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32745136

RESUMO

Hypoxia-activated prodrugs (HAPs) present a conceptually elegant approach to not only overcome, but better yet, exploit intra-tumoural hypoxia. Despite being successful in vitro and in vivo, HAPs are yet to achieve successful results in clinical settings. It has been hypothesised that this lack of clinical success can, in part, be explained by the insufficiently stringent clinical screening selection of determining which tumours are suitable for HAP treatments. Taking a mathematical modelling approach, we investigate how tumour properties and HAP-radiation scheduling influence treatment outcomes in simulated tumours. The following key results are demonstrated in silico: (i) HAP and ionising radiation (IR) monotherapies may attack tumours in dissimilar, and complementary, ways. (ii) HAP-IR scheduling may impact treatment efficacy. (iii) HAPs may function as IR treatment intensifiers. (iv) The spatio-temporal intra-tumoural oxygen landscape may impact HAP efficacy. Our in silico framework is based on an on-lattice, hybrid, multiscale cellular automaton spanning three spatial dimensions. The mathematical model for tumour spheroid growth is parameterised by multicellular tumour spheroid (MCTS) data.


Assuntos
Antineoplásicos/farmacologia , Hipóxia Celular/fisiologia , Modelos Biológicos , Pró-Fármacos/farmacologia , Microambiente Tumoral/fisiologia , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Biologia Computacional , Simulação por Computador , Humanos , Radiação Ionizante , Radioterapia , Esferoides Celulares , Células Tumorais Cultivadas
7.
Nat Commun ; 11(1): 4116, 2020 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-32807793

RESUMO

Glioblastoma contains a rare population of self-renewing brain tumor stem cells (BTSCs) which are endowed with properties to proliferate, spur the growth of new tumors, and at the same time, evade ionizing radiation (IR) and chemotherapy. However, the drivers of BTSC resistance to therapy remain unknown. The cytokine receptor for oncostatin M (OSMR) regulates BTSC proliferation and glioblastoma tumorigenesis. Here, we report our discovery of a mitochondrial OSMR that confers resistance to IR via regulation of oxidative phosphorylation, independent of its role in cell proliferation. Mechanistically, OSMR is targeted to the mitochondrial matrix via the presequence translocase-associated motor complex components, mtHSP70 and TIM44. OSMR interacts with NADH ubiquinone oxidoreductase 1/2 (NDUFS1/2) of complex I and promotes mitochondrial respiration. Deletion of OSMR impairs spare respiratory capacity, increases reactive oxygen species, and sensitizes BTSCs to IR-induced cell death. Importantly, suppression of OSMR improves glioblastoma response to IR and prolongs lifespan.


Assuntos
Glioblastoma/metabolismo , Células-Tronco Neoplásicas/metabolismo , Radiação Ionizante , Receptores de Oncostatina M/metabolismo , Animais , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Masculino , Camundongos , Camundongos SCID , NADH Desidrogenase/genética , NADH Desidrogenase/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Oncostatina M/metabolismo , Estresse Oxidativo/efeitos da radiação , Receptores de Oncostatina M/genética , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos da radiação
8.
Life Sci ; 257: 118087, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32702442

RESUMO

AIMS: Recent studies suggest that direct exposure of cells to fractionated radiotherapy might induce radioresistance. However, the effects of fractionated radiotherapy on the non-irradiated bystander cells remain unclear. We hypothesized that fractionated radiotherapy could enhance radioresistance and proliferation of bystander cells. MAIN METHODS: Human tumor cell lines, including A549 and HT29 were irradiated (2 Gy per day). The irradiated cells (either A549 or HT29) were co-cultured with non-irradiated cells of the same line using transwell co-culture system. Tumor cell proliferation, radioresistance and apoptosis were measured using MTT assay, clonogenic survival assay and Annexin-V in bystander cells, respectively. In addition, activation of Chk1 (Ser 317), Chk2 (Thr 68) and Akt (Ser473) were measured via western blot. KEY FINDINGS: Irradiated HT29 cells induced conventional bystander effects detected as modulation of clonogenic survival parameters (decreased area under curve, D10 and ED50 and increased α) and proliferation in recipient neighbors. While, irradiated A549 cells significantly enhanced the radioresistance and proliferation of bystander cells. These changes were accompanied with enhanced activation of Chk1, Chk2 and Akt in non-irradiated bystander A549 cells. Moreover, both bystander effects (damaging and protective) were mediated through secreted factors. SIGNIFICANCE: These findings suggest that fractionated radiotherapy could promote proliferation and radioresistance of bystander cells probably through survival and proliferation pathways.


Assuntos
Apoptose/efeitos da radiação , Efeito Espectador/efeitos da radiação , Proliferação de Células/efeitos da radiação , Tolerância a Radiação/efeitos da radiação , Células A549 , Sobrevivência Celular/efeitos da radiação , Técnicas de Cocultura , Células HT29 , Humanos
9.
Int J Nanomedicine ; 15: 3771-3790, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547027

RESUMO

Introduction: Rapamycin has been considered as a potential treatment for osteoarthritis (OA). Drug carriers fabricated from liposomes can prolong the effects of drugs and reduce side effects of drugs. Low-intensity pulsed ultrasound (LIPUS) has been found to possess anti-OA effects. Materials and Methods: The anti-osteoarthritic effects of liposome-encapsulated rapamycin (L-rapa) combined with LIPUS were examined by culture of normal and OA chondrocytes in alginate beads and further validated in OA prone Dunkin-Hartley guinea pigs. Results: L-rapa with LIPUS largely up-regulated aggrecan and type II collagen mRNA in human OA chondrocytes (HOACs). L-rapa with LIPUS caused significant enhancement in proteoglycan and type II collagen production in HOACs. Large decreases in both MMP-13 and IL-6 proteins were found in the HOACs exposed to L-rapa with LIPUS. Intra-articular injection of 40 µL L-rapa at both 5 µM and 50 µM twice a week combined with LIPUS thrice a week for 8 weeks significantly increased GAGs and type II collagen in the cartilage of knee. Results on OARSI score showed that intra-articular injection of 5 µM L-rapa with LIPUS displayed the greatest anti-OA effects. Immunohistochemistry revealed that L-rapa with or without LIPUS predominantly reduced MMP-13 in vivo. The values of complete blood count and serum biochemical examinations remained in the normal ranges after the injections with or without LIPUS. These data indicated that intra-articular injection of L-rapa collaborated with LIPUS is not only effective against OA but a safe OA therapy. Conclusion: Taken together, L-rapa combined with LIPUS possessed the most consistently and effectively anabolic and anti-catabolic effects in HOACs and the spontaneous OA guinea pigs. This study evidently revealed that liposome-encapsulation collaborated with LIPUS is able to reduce the effective dose and administration frequency of rapamycin and further stably reinforce its therapeutic actions against OA.


Assuntos
Osteoartrite/terapia , Sirolimo/uso terapêutico , Ondas Ultrassônicas , Animais , Peso Corporal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/patologia , Condrócitos/efeitos da radiação , Colágeno Tipo II/metabolismo , Liberação Controlada de Fármacos , Cobaias , Humanos , Injeções Intra-Articulares , Interleucina-6/metabolismo , Lipossomos/ultraestrutura , Masculino , Metaloproteinase 13 da Matriz/metabolismo , Pessoa de Meia-Idade , Osteoartrite/sangue , Osteoartrite/patologia , Proteoglicanas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sirolimo/administração & dosagem , Sirolimo/farmacologia
10.
Prostate ; 80(12): 986-992, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32557725

RESUMO

BACKGROUND: Focal therapies for prostate cancer (PC) can reduce adverse events and do not lead to androgen-independent progression. Ultrasound could be used for cancer treatments if the repetition frequency is fitted to the purpose. We investigated the possible therapeutic effect of ultrasound irradiation on PC cells. MATERIALS AND METHODS: We irradiated two PC cell lines, androgen-dependent LNCaP and -independent PC-3 with ultrasound (3.0 W/cm2 , 3 MHz, irradiation time rate: 20%) for 2 minutes for 1 day or 3 consecutive days at a repetition frequency of 1, 10, or 100 Hz in vitro. Cell proliferation and apoptosis were determined after irradiation. RESULTS: Cell proliferation of PC-3 was significantly inhibited after 1 day (P < .0001) and 3 days (P < .0001) of 10 Hz ultrasound irradiation, and that of LNCaP after 1 day (P < .0001) and 3 days (P < .0001) of irradiation. LNCaP was more sensitive to ultrasound at both lower and higher cell density but PC-3 was only sensitive at a lower cell density (P < .01). Irradiation with 10 Hz ultrasound-induced significantly more PC-3 apoptotic cells than control (1 day, P = .0137; 3 days, P = .0386) rather than irradiation with 1 Hz. Apoptosis via caspase-3 was induced at 10 Hz in 1-day (P < .05) irradiation in both cell lines. CONCLUSIONS: Ultrasound irradiation with even 1 day of 10 Hz significantly inhibited cell proliferation in both LNCaP and PC-3, especially by the remarkable induction of apoptosis in vitro. Our study indicated that ultrasound irradiation can be a therapeutic option for PC and further studies in vivo will be undertaken.


Assuntos
Neoplasias da Próstata/radioterapia , Terapia por Ultrassom/métodos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Humanos , Masculino , Células PC-3 , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/radioterapia
11.
J Food Sci ; 85(6): 1924-1931, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32418198

RESUMO

Radioresistance is an important factor affecting the radiotherapy effect of colorectal cancer (CRC). Allicin is a versatile sulfur-containing organic compound extracted from garlic (Allium sativum L.), which has many pharmacological effects. However, the effect of allicin on the sensitivity of CRC radiotherapy has not been confirmed. The present study is to observe the radiosensitivity effects of allicin and to explore its mechanism in CRC radiotherapy. The proliferation inhibition effects of allicin combined with X-ray radiotherapy in HCT116 cells were measured by growth curve of cell and colony formation assays. The cell apoptosis was detected by Hoechst 33258 nucleus staining assay. The migration ability of cells was detected by Transwell chamber migration assay. The animal model of CRC was established in BALB/c mice via transplantation of CT26 cell, and the radiosensitization effect of allicin on CRC was detected in vivo. The mRNA expressions of NF-κB, IKKß, and IκBα were analyzed by reverse transcription-polymerase chain reaction (RT-PCR). The protein expressions of NF-κB, p-NF-κB, IKKß, p-IKKß, IκBα, and p-IκBα were detected by western blotting. Our results showed that allicin improves the sensitivity of X-ray radiotherapy in CRC, and its mechanism may be associated with inhibition of NF-κB signaling pathway. These findings suggest that allicin may be used as a potential sensitizer for tumor radiotherapy in the clinic.


Assuntos
Neoplasias Colorretais/radioterapia , NF-kappa B/metabolismo , Ácidos Sulfínicos/administração & dosagem , Animais , Apoptose/efeitos da radiação , Proliferação de Células/efeitos da radiação , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/metabolismo , NF-kappa B/genética , Tolerância a Radiação , Transdução de Sinais/efeitos da radiação
12.
Anticancer Res ; 40(4): 1981-1988, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234887

RESUMO

BACKGROUND/AIM: We aimed to elucidate the pathological findings following acute and late re-irradiation in a preclinical model. MATERIALS AND METHODS: Mice were divided into five treatment groups: sham-irradiation (Sham-IR), 10-12 Gy (Single IR Acute), 15 Gy (Single IR Late), 15 Gy followed by 10-12 Gy re-irradiation 7 days later (Re-IR Acute), or 15 Gy followed by 10-12 Gy re-irradiation 12 weeks later (Re-IR Late). Mice were sacrificed after either single irradiation or re-irradiation for pathological assessment. RESULTS: The Re-IR Late group had significantly lower numbers of crypts with apoptotic cells than those observed in mice in the Single IR Acute group. There were no significant differences between the Single IR Acute and re-IR Acute groups in cell proliferation or in a crypt survival assay. CONCLUSION: Re-irradiation with a long interval after the first irradiation may cause similar acute biological effects in normal intestine as observed following irradiation without re-irradiation.


Assuntos
Apoptose/efeitos da radiação , Proliferação de Células/efeitos da radiação , Intestinos/efeitos da radiação , Lesões Experimentais por Radiação/fisiopatologia , Animais , Humanos , Intestinos/fisiopatologia , Camundongos , Modelos Animais , Reirradiação/efeitos adversos
13.
Am J Physiol Renal Physiol ; 318(5): F1167-F1176, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32223312

RESUMO

Cellular senescence, a permanent arrest of cell proliferation, is characterized by a senescence-associated secretory phenotype (SASP), which reinforces senescence and exerts noxious effects on adjacent cells. Recent studies have suggested that transplanting small numbers of senescent cells suffices to provoke tissue inflammation. We hypothesized that senescent cells can directly augment renal injury. Primary scattered tubular-like cells (STCs) acquired from pig kidneys were irradiated by 10 Gy of cesium radiation, and 3 wk later cells were characterized for levels of senescence and SASP markers. Control or senescent STCs were then prelabeled and injected (5 × 105 cells) into the aorta of C57BL/6J mice. Four weeks later, renal oxygenation was studied in vivo using 16.4-T magnetic resonance imaging and function by plasma creatinine level. Renal markers of SASP, fibrosis, and microvascular density were evaluated ex vivo. Per flow cytometry, irradiation induced senescence in 80-99% of STCs, which showed increased gene expression of senescence and SASP markers, senescence-associated ß-galactosidase staining, and cytokine levels (especially IL-6) secreted in conditioned medium. Four weeks after injection, cells were detected engrafted in the mouse kidneys with no evidence for rejection. Plasma creatinine and renal tissue hypoxia increased in senescent compared with control cells. Senescent kidneys were more fibrotic, with fewer CD31+ endothelial cells, and showed upregulation of IL-6 gene expression. Therefore, exogenously delivered senescent renal STCs directly injure healthy mouse kidneys. Additional studies are needed to determine the role of endogenous cellular senescence in the pathogenesis of kidney injury and evaluate the utility of senolytic therapy.


Assuntos
Proliferação de Células , Senescência Celular , Túbulos Renais/transplante , Rim/cirurgia , Animais , Proliferação de Células/efeitos da radiação , Células Cultivadas , Senescência Celular/efeitos da radiação , Feminino , Fibrose , Mediadores da Inflamação/metabolismo , Rim/metabolismo , Rim/patologia , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Túbulos Renais/efeitos da radiação , Masculino , Camundongos Endogâmicos C57BL , Fenótipo , Sus scrofa , Transplante Heterólogo
14.
Tissue Cell ; 63: 101329, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32223956

RESUMO

To investigate the protective function of low-level laser irradiation (LLLI) against ionizing irradiation and explore the molecular mechanism of photomodulation of Nrf2 protein, the impact of LLLI (635 nm, 5.7 J/cm2) before 2 Gy gamma ray radiation of radio-sensitive tissue hematopoietic stem cells was evaluated. As a result, reduced levels of reactive oxygen species and increased expression of antioxidant enzymes were detected. Moreover, increased expression of Nrf2 was observed after LLLI, whereas brusatol pretreatment before LLLI abolished this effect. In vivo, transplantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) was employed for therapy of hematopoietic function in an acute radiation sickness (H-ARS) mouse model, which was induced by 6-Gy ionizing irradiation; different hUC-MSC pretreatments including LLLI and Nrf2 RNAi were accounted for during experimental grouping. LLLI treatment of cells significantly increased the erythrocyte count and number of myelopoiesis clones (P < 0.05), but such improvements were reduced by Nrf2 RNAi pretreatment compared with cells transplanted without intervention. Therefore, LLLI may improve the radiation protection effect through molecular mechanisms related to the Nrf2 antioxidant pathway.


Assuntos
Proliferação de Células/efeitos da radiação , Células-Tronco Mesenquimais/efeitos da radiação , Fator 2 Relacionado a NF-E2/genética , Animais , Antioxidantes/metabolismo , Diferenciação Celular/efeitos da radiação , Linhagem Celular , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Lasers/efeitos adversos , Transplante de Células-Tronco Mesenquimais , Camundongos , Proteção Radiológica , Cordão Umbilical/efeitos da radiação
15.
Aquat Toxicol ; 222: 105468, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32199137

RESUMO

The extracellular matrix (ECM) is a non-cellular and three-dimensional structure, constituted by a macromolecular dynamic network that involves the cells in all animal tissues, including embryonic ones. Several studies with vertebrates and cell cultures have reported deleterious effects of ultraviolet-B (UVB) radiation on the components associated with the ECM. However, studies focusing on the UVB radiation effects on ECM components of crustaceans during embryonic development are very scarce. Thus, the aim of this study was to identify the coding sequences of components associated with the ECM and to evaluate the effect of UVB radiation on embryos of the ecologically-important decapod Macrobrachium olfersii. To evaluate the modulation of these ECM components during embryonic development, the transcript levels of Col4α1, Itgß, Lamα, Mmp1 and Timp in M. olfersii embryos were analyzed at early developmental stages (E1, E3 and E4), intermediate developmental stage (E7) and late developmental stages (E10 and E14). In addition, embryos at E7, which correspond to a landmark of crustacean development, were analyzed after 12 h of UVB exposure to verify UVB effects on the ECM components. The ECM component sequences were similar to other decapods, suggesting conservation of these genes among crustaceans. The results showed modulations of the ECM components of M. olfersii embryos that reflect the need for each component in the cellular mechanisms, necessary for normal embryonic development. After UVB exposure, embryos showed opacity of embryonic tissues and it was found the overexpression of Col4α1, Itgß, Mmp1 and Timp transcript levels (1.82-, 1.52-, 2.34- and 6.27-fold, respectively). These impairments can compromise important events for normal embryonic development, such as growth of optic lobes, caudal papilla, ramification of appendages and differentiation of organic systems. The results presented here, together with the effects on morphology, cell proliferation, differentiation, and apoptosis demonstrated previously, strengthen the knowledge of the complex impacts of UVB radiation on freshwater embryos. Nevertheless, our results encourage further investigations focusing on the assessment of UVB effects on different organisms in order to better understand the myriad of UVB effects on ECM components.


Assuntos
Embrião não Mamífero/efeitos da radiação , Desenvolvimento Embrionário/efeitos da radiação , Matriz Extracelular/efeitos da radiação , Palaemonidae/efeitos da radiação , Transcrição Genética/efeitos da radiação , Raios Ultravioleta , Animais , Apoptose/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Embrião não Mamífero/metabolismo , Embrião não Mamífero/patologia , Desenvolvimento Embrionário/genética , Matriz Extracelular/genética , Água Doce/química , Palaemonidae/genética , Palaemonidae/crescimento & desenvolvimento
16.
Arch Biochem Biophys ; 685: 108333, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32194044

RESUMO

This study summarizes the available evidence from systematic reviews on the in vitro effects of photobiomodulation on the proliferation and differentiation of human bone and stromal cells by appraising their methodological quality. Improvements for future studies are also highlighted, with particular emphasis on in vitro protocols and cell-related characteristics. Six reviews using explicit eligibility criteria and methods selected in order to minimize bias were included. There was no compelling evidence on the cellular mechanisms of action or treatment parameters of photobiomodulation; compliance with quality assessment was poor. A rigorous description of laser parameters (wavelength, power, beam spot size, power density, energy density, repetition rate, pulse duration or duty cycle, exposure duration, frequency of treatments, and total radiant energy), exposure conditions (methods to ensure a uniform irradiation and to avoid cross-irradiation, laser-cell culture surface distance, lid presence during irradiation) and cell-related characteristics (cell type or line, isolation and culture conditions, donor-related factors where applicable, tissue source, cell phenotype, cell density, number of cell passages in culture) should be included among eligibility criteria for study inclusion. These methodological improvements will maximize the contribution of in vitro studies on the effects of photobiomodulation on human bone and stromal cells to evidence-based translational research.


Assuntos
Terapia com Luz de Baixa Intensidade , Osteócitos/metabolismo , Células Estromais/metabolismo , Animais , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Humanos , Osteócitos/efeitos da radiação , Células Estromais/efeitos da radiação , Revisões Sistemáticas como Assunto
17.
PLoS One ; 15(3): e0229272, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119704

RESUMO

BACKGROUND AND AIMS: Radiotherapy is one of the major remedies for the treatment of cancer, including nasopharyngeal carcinoma (NPC). Radioresistance occurs very often in target cells that is a large drawback in cancer treated with radiotherapy. Livin involves the over-growth of cancer cells. This study aims to investigate the role of livin in the radioresistance formation in NPC cells. METHODS: NPC cell lines were exposed to small doses of irradiation to establish a cell model of radioresistance, in which the role of livin in the development of radioresistance was evaluated. RESULTS: The expression of livin was observed in NPC cells, which was significantly increased after exposing to small doses of irradiation. A negative correlation was detected between livin and Fas expression in NPC cells. Livin formed a complex with heat shock factor-1 (HSF1, the transcription factor of Fas) in NPC cells after irradiation, which sped up ubiquitination of HSF1. Livin was involved in suppressing Fas expression in NPC cells with radioresistance. Exposure to livin inhibitors prevented radioresistance development and overcame the established radioresistance in NPC cells. CONCLUSIONS: Livin expression in NPC cells plays a critical role in the development of radioresistance. Depletion of livin increases the sensitiveness of NPC cells to irradiation. Target therapy against livin may have the translational potential for the treatment of NPC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Carcinoma Nasofaríngeo/metabolismo , Neoplasias Nasofaríngeas/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Tolerância a Radiação , Regulação para Cima , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , 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 , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Fatores de Transcrição de Choque Térmico/metabolismo , Humanos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/radioterapia , Proteínas de Neoplasias/antagonistas & inibidores , Peptídeos/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Transdução de Sinais , Ubiquitinação , Regulação para Cima/efeitos dos fármacos , Receptor fas/metabolismo
18.
Radiat Res ; 193(5): 481-496, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32196412

RESUMO

During fractionated radiotherapy, epithelial cell populations are thought to decrease initially, followed by accelerated repopulation to compensate cell loss. However, previous findings in skin with daily 1.1 Gy dose fractions indicate continued and increasing cell depletion. Here we investigated epidermal keratinocyte response with daily 2 Gy fractions as well as accelerated and hypofractionation. Epidermal interfollicular melanocytes were also assessed. Skin-punch biopsies were collected from breast cancer patients before, during and after mastectomy radiotherapy to the thoracic wall with daily 2 Gy fractions for 5 weeks. In addition, 2.4 Gy radiotherapy four times per week and 4 Gy fractions twice per week for 5 weeks, and two times 2 Gy daily for 2.5 weeks, were used. Basal keratinocyte density of the interfollicular epidermis was determined and immunostainings of keratinocytes for DNA double-strand break (DSB) foci, growth arrest, apoptosis and mitosis were quantified. In addition, interfollicular melanocytes were counted. Initially minimal keratinocyte loss was observed followed by pronounced depletion during the second half of treatment and full recovery at 2 weeks post treatment. DSB foci per cell peaked towards the end of treatment. p21-stained cell counts increased during radiotherapy, especially the second half. Apoptotic frequency was low throughout radiotherapy but increased at treatment end. Mitotic cell count was significantly suppressed throughout radiotherapy and did not recover during weekend treatment gaps, but increased more than threefold compared to unexposed skin 2 weeks post-radiotherapy. The number of melanocytes remained constant over the study period. Germinal keratinocyte loss rate increased gradually during daily 2 Gy fractions for 5 weeks, and similarly for hypofractionation. DSB foci number after 2 Gy irradiation revealed an initial radioresistance followed by increasing radiosensitivity. Growth arrest mediated by p21 strongly suggests that cells within or recruited into the cell cycle during treatment are at high risk of loss and do not contribute significantly to repopulation. It is possible that quiescent (G0) cells at treatment completion accounted for the accelerated post-treatment repopulation. Recent knowledge of epidermal tissue regeneration and cell cycle progression during genotoxic and mitogen stress allows for a credible explanation of the current finding. Melanocytes were radioresistant regarding cell depletion.


Assuntos
Apoptose/efeitos da radiação , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Epiderme/efeitos da radiação , Queratinócitos/efeitos da radiação , Melanócitos/efeitos da radiação , Tolerância a Radiação , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Melanócitos/citologia , Melanócitos/metabolismo , Fatores de Tempo
19.
Radiat Res ; 193(6): 520-530, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32216710

RESUMO

Genetic and epigenetic profile changes associated with individual radiation sensitivity are well documented and have led to enhanced understanding of the mechanisms of the radiation-induced DNA damage response. However, the search continues to identify reliable biomarkers of individual radiation sensitivity. Herein, we report on a multi-biomarker approach using traditional cytogenetic biomarkers, DNA damage biomarkers and transcriptional microRNA (miR) biomarkers coupled with their potential gene targets to identify radiosensitivity in ataxia-telangiectasia mutated (ATM)-deficient lymphoblastoid cell lines (LCL); ATM-proficient cell lines were used as controls. Cells were 0.05 and 0.5 Gy irradiated, using a linear accelerator, with sham-irradiated cells as controls. At 1 h postirradiation, cells were fixed for γ-H2AX analysis as a measurement of DNA damage, and cytogenetic analysis using the G2 chromosomal sensitivity assay, G-banding and FISH techniques. RNA was also isolated for genetic profiling by microRNA (miR) and RT-PCR analysis. A panel of 752 miR were analyzed, and potential target genes, phosphatase and tensin homolog (PTEN) and cyclin D1 (CCND1), were measured. The cytogenetic assays revealed that although the control cell line had functional cell cycle checkpoints, the radiosensitivity of the control and AT cell lines were similar. Analysis of DNA damage in all cell lines, including an additional control cell line, showed elevated γ-H2AX levels for only one AT cell line. Of the 752 miR analyzed, eight miR were upregulated, and six miR were downregulated in the AT cells compared to the control. Upregulated miR-152-3p, miR-24-5p and miR-92-15p and all downregulated miR were indicated as modulators of PTEN and CCDN1. Further measurement of both genes validated their potential role as radiation-response biomarkers. The multi-biomarker approach not only revealed potential candidates for radiation response, but provided additional mechanistic insights into the response in AT-deficient cells.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Ciclina D1/metabolismo , Linfócitos/metabolismo , Linfócitos/efeitos da radiação , MicroRNAs/genética , PTEN Fosfo-Hidrolase/metabolismo , Biomarcadores/metabolismo , Linhagem Celular , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Dano ao DNA , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Linfócitos/citologia
20.
Gene ; 738: 144485, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32087272

RESUMO

Impairment of neurogenesis is thought to be one of the important mechanisms underlying radiation-induced cognitive decline. Self-renewal and differentiation of neural stem cells (NSCs) are important components of neurogenesis. It has been well established that autophagy plays an important role in neurodegenerative conditions, however, its role in radiation-induced cognitive decline remains unclear. Our previous studies have found that ionizing radiation (IR) induces autophagy in mouse neurons, and minocycline, an antibiotic that can cross the blood-brain barrier, protects neurons from radiation-induced apoptosis through promoting autophagy, thus may contribute to the improvement of mouse cognitive performance after whole-brain irradiation. In the present study, we investigated whether autophagy is involved in radiation-induced damage in self-renewal and differentiation of NSCs. We found that NSCs were extremely sensitive to IR. Irradiation induced autophagy in NSCs in a dose-dependent manner. Atg7 knockdown significantly decreased autophagy, thus increased the apoptosis levels in irradiated NSCs, suggesting that autophagy protected NSCs from radiation-induced apoptosis. Moreover, compared with the negative control NSCs, the neurosphere size was significantly reduced and the neuronal differentiation was notably inhibited in Atg7-deficient NSCs after irradiation, indicating that autophagy defect could exacerbate radiation-induced reduction in NSC self-renewal and differentiation potential. In conclusion, down-regulating autophagy by selective Atg7 knockdown in NSCs enhanced radiation-induced NSC damage, suggesting an important protective role of autophagy in maintaining neurogenesis. Along with the protective effect of autophagy on irradiated neurons, our results on NSCs not only shed the light on the involvement of autophagy in the development of radiation-induced cognitive decline, but also provided a potential target for preventing cognitive impairment after cranial radiation exposure.


Assuntos
Proteína 7 Relacionada à Autofagia/metabolismo , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/efeitos da radiação , Animais , Apoptose/efeitos da radiação , Autofagia/efeitos da radiação , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Neurogênese/efeitos da radiação , Neurônios/efeitos da radiação , Gravidez , Radiação Ionizante
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