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1.
Life Sci ; 286: 120051, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34666039

RESUMO

AIMS: To overcome radioresistant cancer cells, clinically relevant radioresistant (CRR) cells were established. To maintain their radioresistance, CRR cells were exposed 2 Gy/day of X-rays daily (maintenance irradiation: MI). To understand whether the radioresistance induced by X-rays was reversible or irreversible, the difference between CRR cells and those without MI for a year (CRR-NoIR cells) was investigated by the mitochondrial function as an index. MAIN METHODS: Radiation sensitivity was determined by modified high density survival assay. Mitochondrial membrane potential (Δψm) was determined by 5,5',6,6'-tetrachloro-1,1', tetraethylbenzimidazolocarbo-cyanine iodide (JC-1) staining. Rapid Glucose-Galactose assay was performed to determine the shift in their energy metabolism from aerobic glycolysis to oxidative phosphorylation in CRR cells. Involvement of prohibitin-1 (PHB1) in Δψm was evaluated by knockdown of PHB1 gene followed by real-time PCR. KEY FINDINGS: CRR cells that exhibited resistant to 2 Gy/day X-ray lost their radioresistance after more than one year of culture without MI for a year. In addition, CRR cells lost their radioresistance when the mitochondria were activated by galactose. Furthermore, Δψm were increased and PHB1 expression was down-regulated, in the process of losing their radioresistance. SIGNIFICANCE: Our finding reveled that tune regulation of mitochondrial function is implicated in radioresistance phenotype of cancer cells. Moreover, as our findings indicate, though further studies are required to clarify the precise mechanisms underlying cancer cell radioresistance, radioresistant cells induced by irradiation and cancer stem cells that are originally radioresistant should be considered separately, the radioresistance of CRR cells is reversible.

2.
Genes (Basel) ; 12(9)2021 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-34573330

RESUMO

Mitochondria are very important intracellular organelles because they have various functions. They produce ATP, are involved in cell signaling and cell death, and are a major source of reactive oxygen species (ROS). Mitochondria have their own DNA (mtDNA) and mutation of mtDNA or change the mtDNA copy numbers leads to disease, cancer chemo/radioresistance and aging including longevity. In this review, we discuss the mtDNA mutation, mitochondrial disease, longevity, and importance of mitochondrial dysfunction in cancer first. In the later part, we particularly focus on the role in cancer resistance and the mitochondrial condition such as mtDNA copy number, mitochondrial membrane potential, ROS levels, and ATP production. We suggest a therapeutic strategy employing mitochondrial transplantation (mtTP) for treatment-resistant cancer.

3.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361070

RESUMO

In cancer therapy, radioresistance or chemoresistance cells are major problems. We established clinically relevant radioresistant (CRR) cells that can survive over 30 days after 2 Gy/day X-ray exposures. These cells also show resistance to anticancer agents and hydrogen peroxide (H2O2). We have previously demonstrated that all the CRR cells examined had up-regulated miR-7-5p and after miR-7-5p knockdown, they lost radioresistance. However, the mechanism of losing radioresistance remains to be elucidated. Therefore, we investigated the role of miR-7-5p in radioresistance by knockdown of miR-7-5p using CRR cells. As a result, knockdown of miR-7-5p increased reactive oxygen species (ROS), mitochondrial membrane potential, and intracellular Fe2+ amount. Furthermore, miR-7-5p knockdown results in the down-regulation of the iron storage gene expression such as ferritin, up-regulation of the ferroptosis marker ALOX12 gene expression, and increases of Liperfluo amount. H2O2 treatment after ALOX12 overexpression led to the enhancement of intracellular H2O2 amount and lipid peroxidation. By contrast, miR-7-5p knockdown seemed not to be involved in COX-2 and glycolysis signaling but affected the morphology of CRR cells. These results indicate that miR-7-5p control radioresistance via ROS generation that leads to ferroptosis.


Assuntos
Ferroptose , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Bucais/patologia , Tolerância a Radiação , Espécies Reativas de Oxigênio/metabolismo , Araquidonato 12-Lipoxigenase/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/metabolismo , Potencial da Membrana Mitocondrial , Neoplasias Bucais/genética , Neoplasias Bucais/radioterapia , Transdução de Sinais , Células Tumorais Cultivadas
4.
Pharmacol Biochem Behav ; 209: 173257, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34418452

RESUMO

Metoprine increases the content of histamine in brain by inhibiting histamine N-methyltransferase (HMT), a centrally acting histamine degrading enzyme. We present data demonstrating that pretreatment with metoprine attenuates the hyperlocomotive effects of METH in mice using a multi-configuration behavior apparatus designed to monitor four behavioral outcomes [horizontal locomotion, appetitive behavior (food access), and food and water intake]. Metoprine pretreatment itself induced hyperlocomotion in mice challenged with saline during the large part of light phase. The trend was also observed during the following dark phase. This is the first report that metoprine has a long-lasting locomotor stimulating property. Similarly, in a tail suspension test, a single injection of metoprine significantly reduced total time of immobility in mice, consistent with the idea that metoprine possesses motor stimulating properties. Metoprine pretreatment did not affect other aspects of behavior. Metoprine did not affect the appetitive and drinking behavior while exerted an effect on stereotypy. No stereotyped behavior was observed in mice pretreated with vehicle followed by METH, while stereotyped sniffing was observed in mice pretreated with metoprine followed by METH. The metoprine pretreatment attenuated METH-induced hyperlocomotion during the first 2 h of light phase, suggesting that metoprine-induced locomotor stimulating property might be different from that of METH. The hypothalamic content of histamine (but not its brain metabolite) was increased after metoprine or METH administration. Both METH and metoprine reduced dopamine and histamine turnover in the striatum and the nucleus accumbens and the hypothalamus, respectively, and there is a significant metoprine pretreatment x METH challenge interaction in the histamine turnover. It is likely that metoprine may attenuate METH-induced hyperlocomotion via activation of histaminergic neurotransmission. Metoprine also might induce a long-lasting locomotor stimulating effect via a putative mechanism different from that whereby METH induces the locomotor stimulating effect.

5.
Brain Res ; 1768: 147580, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34260963

RESUMO

Kamishoyosan (KSS), a Japanese traditional herbal formula, is used to treat symptoms related to the autonomic nervous system in men and women; it is especially known for improving the symptoms of irritability (e.g., bad temper and persistent anger). Although clinical and ethological studies of KSS have been conducted, its efficacy in reducing irritability remains to be validated. In the present study, male and female ddY-strain mice were isolation-reared for 8 weeks (from the third postnatal week) to induce pathologically aggressive biting behavior (ABB), which was used as an indicator of irritability. The ABB of mice toward metal rods was measured using the Aggressive Response Meter. An intraperitoneal administration of KSS (100 mg/kg) effectively reduced ABB in male and female mice at 2 h after the administration; however, this effect was canceled by prior administration of WAY-100635 [a 5-hydroxytryptoamine (5-HT)-1A receptor antagonist; 0.5 mg/kg] and bicuculline (a type-A gamma-aminobutyric acid receptor antagonist; 1.0 mg/kg). Additionally, tamoxifen, ICI-182780, and G-15 (all estrogen receptor antagonists) inhibited the action of KSS in a dose-dependent manner. Furthermore, gene expression of tryptophan hydroxylase (Tph) 1 and Tph2 were increased and 5-HT immunofluorescence was slightly increased in the dorsal raphe nucleus (DRN) of isolation-reared mice administered with KSS. Collectively, these results indicate that KSS effectively reduces ABB in isolation-reared male and female mice through stimulation of 5-HT production in the DRN. Our findings also suggest that gene expression of estrogen receptor (Esr) 2 increased in the DRN might be associated with the reduction of ABB.

6.
J Radiat Res ; 62(1): 12-24, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33231252

RESUMO

Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/-, p53-/-) and Hd-rR HNI hybrid (p53+/-) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/- fish than in p53-/- fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.


Assuntos
Carcinogênese/genética , Carcinogênese/efeitos da radiação , Ciprinodontiformes/genética , Radiação Ionizante , Transgenes , Animais , Animais Geneticamente Modificados , Carcinogênese/patologia , Relação Dose-Resposta à Radiação , Proteínas de Peixes/genética , Raios gama , Hibridização Genética , Hiperpigmentação/genética , Receptores Proteína Tirosina Quinases/genética , Proteína Supressora de Tumor p53/genética
7.
Peptides ; 150: 170734, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-34974081

RESUMO

Inflammation, especially neuroinflammation, which is caused by stress, leads to central nervous system (CNS) dysfunction. Because lipopolysaccharides (LPSs) cause neuroinflammation, we investigated the effect of LPSs to CNS. In PC-12 cells, LPSs derived from oral bacteria reduced the expression of KCC2, a Cl- transporter. LPS derived from P. gingivalis (P. g) administered to rat primary cultured cells also reduced the KCC2 expression. However, LPSs derived from E. coli did not reduce the KCC2 expression. LPS treatment activated TLR4, IL-1ß, and REST gene expressions, which led to KCC2 inactivation in PC-12 cells. The mechanism of KCC2 has been shown to play an important role in brain maturation, function (such as the GABA switch), and behavioral problems, we investigated the GABA function. We found that the GABA function was changed from inhibitory to excitatory by the LPS derived from P. g treatment. We demonstrated that the GSK3ß also involved in the KCC2 reduction by LPS treatment. We show that oxytocin rescued the reduction in KCC2 expression caused by LPSs by inhibiting GSK3ß signaling but vasopressin could not. Considered together, our results indicate that the LPSs from oral bacteria but not the LPS from E. coli increase the risk for brain disorders and oxytocin might be a candidate to overcome the abnormal behavior caused by brain disorders such as psychiatric disorders.

8.
Technol Cancer Res Treat ; 19: 1533033820980077, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33334271

RESUMO

BACKGROUND: Radiation therapy is a highly cost-effective treatment for cancer, but the existence of radio-resistant cells remains the most critical obstacle in radiotherapy. We have been established clinically relevant radioresistant (CRR) cell lines by exposure to a stepwise increase of fractionated X-rays. We are trying to overcome the radio-resistance by analyzing the properties of these cells. In this study, we tried to evaluate the effects of hydrogen peroxide (H2O2) on the CRR cells because this can evaluate the efficacy of Kochi Oxydol-Radiation Therapy for Unresectable Carcinomas (KORTUC) that treats H2O2 before irradiation. We also established H2O2-resistant cells to compare the radiation and H2O2 resistant phenotype. MATERIALS AND METHODS: We used human cancer cell lines derived from hepatoblastoma (HepG2), oral squamous cell carcinoma (SAS), and cervical cancer (HeLa). We established HepG2, SAS, and HeLa CRR cells and HepG2, SAS, and HeLa H2O2-resistant cells. To evaluate their sensitivity to radiation or H2O2, high-density survival assay, or WST assay was performed. CellROXTM was used to detect intracellular Reactive Oxygen Species (ROS). RESULTS: CRR cells were resistant to H2O2-induced cell death but H2O2-resistant cells were not resistant to irradiation. This phenotype of CRR cells was irreversible. The intracellular ROS was increased in parental cells after H2O2 treatment for 3 h, but in CRR cells, no significant increase was observed. CONCLUSION: Fractionated X-ray exposure induces H2O2 resistance in CRR cells. Therefore, it is necessary to carry out cancer therapy such as KORTUC with the presence of these resistant cells in mind, and as the next stage, it would be necessary to investigate the appearance rate of these cells immediately and take countermeasures.


Assuntos
Peróxido de Hidrogênio/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Radiação Ionizante , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Humanos , Espécies Reativas de Oxigênio/metabolismo , Raios X
9.
Free Radic Biol Med ; 161: 60-70, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33017631

RESUMO

Most anti-cancer agents and radiotherapy exert their therapeutic effects via the production of free radicals. Ferroptosis is a recently described cell death process that is accompanied by iron-dependent lipid peroxidation. Hydrogen peroxide (H2O2) has been reported to induce cell death. However, it remains controversial whether H2O2-induced cell death is ferroptosis. In the present study, we aimed to elucidate the involvement of mitochondria in H2O2-induced ferroptosis and examined the molecules that regulate ferroptosis. We found that one mechanism underlying H2O2-induced cell death is ferroptosis, which occurs soon after H2O2 treatment (within 3 h after H2O2 treatment). We also investigated the involvement of mitochondria in H2O2-induced ferroptosis using mitochondrial DNA-depleted ρ0 cells because ρ0 cells produce more lipid peroxidation, hydroxyl radicals (•OH), and are more sensitive to H2O2 treatment. We found that ρ0 cells contain high Fe2+ levels that lead to •OH production by H2O2. Further, we observed that aquaporin (AQP) 3, 5, and 8 bind nicotinamide-adenine dinucleotide phosphate oxidase 2 and regulate the permeability of extracellular H2O2, thereby contributing to ferroptosis. Additionally, the role of mitochondria in ferroptosis was investigated using mitochondrial transfer in ρ0 cells. When mitochondria were transferred into ρ0 cells, the cells exhibited no sensitivity to H2O2-induced cytotoxicity because of decreased Fe2+ levels. Moreover, mitochondrial transfer upregulated the mitochondrial quality control protein prohibitin 2 (PHB2), which contributes to reduced AQP expression. Our findings also revealed the involvement of AQP and PHB2 in ferroptosis. Our results indicate that H2O2 treatment enhances AQP expression, Fe2+ level, and lipid peroxidation, and decrease mitochondrial function by downregulating PHB2, and thus, is a promising modality for effective cancer treatment.


Assuntos
Aquaporinas , Ferroptose , Mitocôndrias , Aquaporinas/metabolismo , Células HeLa , Humanos , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , Mitocôndrias/metabolismo , Permeabilidade
10.
Mol Biol Rep ; 47(6): 4401-4411, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32394308

RESUMO

Mitochondrial dysfunction is known to contribute to cancer initiation, progression, and chemo-and radio-resistance. However, the precise role of mitochondria in cancer is controversial. Hence, here we tried to further clarify the role of mitochondria in cancer by transferring healthy mitochondria to cancer cells, and also to cells with depleted mitochondrial DNA (ρ0). Healthy mitochondria were isolated from WI-38 cells and were transferred to HeLa, SAS, HeLa ρ0, and SAS ρ0 cells. Then, cell proliferation was verified. In addition, the cells were treated by different concentrations of cisplatin and assessed for apoptosis induction and quantifying the mRNA expression of apoptosis-related genes. Results revealed that incubation of the HeLa, SAS and HeLa ρ0 cells with 5 µg/ml of the isolated mitochondria for 24 h significantly (p < 0.001) increased cell proliferation compared to non-treated controls. Interestingly, the mitochondria transfer rescued the ρ0 cells and made them capable of growing under conventional culture medium. However, the number of apoptotic cells was significantly higher in the HeLa ρ0 cells that received the mitochondria (HeLa-Fibro-Mit) compared to the HeLa ρ0. Furthermore, the expression level of BCL-2 anti-apoptotic gene was down-regulated in both HeLa-Fibro-Mit and SAS-Fibro-Mit cell lines while the expression levels of the BAX, caspase8, caspase9, and AIF pro-apoptotic genes were upregulated. Our findings indicated that although the response of cancer cells to the mitochondria transfer is cancer-type dependent, but the introduction of normal exogenous mitochondria to some cancer cells might be considered as a potential novel therapeutic strategy.


Assuntos
Fibroblastos/metabolismo , Mitocôndrias/metabolismo , Neoplasias/metabolismo , Apoptose/efeitos dos fármacos , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Cisplatino/farmacologia , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
11.
Biochem Biophys Res Commun ; 518(4): 712-718, 2019 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-31472959

RESUMO

MicroRNA (miRNA) is a non-coding RNA involved in regulating both cancer gene promotion and suppression. We investigated the role of miRNA in inducing radiation resistance in cancer cell lines using clinically relevant radioresistant (CRR) cells. Analysis using miRNA arrays and qPCR revealed that miR-7-5p is highly expressed in all examined CRR cells. Additionally, CRR cells lose their radioresistance when daily irradiation is interrupted for over 6 months. MiR-7-5p expression is reduced in these cells, and treating CRR cells with a miR-7-5p inhibitor leads to a loss of resistance to irradiation. Conversely, overexpression of miR-7-5p in CRR cells using a miR-7-5p mimic shows further resistance to radiation. Overexpression of miR-7-5p in parent cells also results in resistance to radiation. These results indicate that miR-7-5p may control radioresistance in various cancer cells at the clinically relevant dose of irradiation. Furthermore, miR-7-5p downregulates mitoferrin and reduces Fe2+, which influences ferroptosis. Our findings have great potential not only for examining radiation resistance prior to treatment but also for providing new therapeutic agents for treatment-resistant cancers.


Assuntos
Espaço Intracelular/metabolismo , Ferro/metabolismo , MicroRNAs/genética , Tolerância a Radiação/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Relação Dose-Resposta à Radiação , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Células HeLa , Células Hep G2 , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Interferência de RNA , Tolerância a Radiação/genética
12.
Cancer Sci ; 110(9): 2856-2866, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31314163

RESUMO

4-Hydroxynonenal (HNE) is an important product of plasma membrane lipid peroxidation, which is a cause of cell and tissue injury. Mitochondrial DNA (mtDNA)-depleted ρ0 cells were established using human cervical cancer and oral squamous cell carcinoma cell lines. We investigated the effect of reactive oxygen species in ρ0 cells, especially the mechanism of hydrogen peroxide (H2 O2 )-mediated cell death. These cell were subjected to high oxidative stress and, compared with their parental cells, showed greater sensitivity to H2 O2 and high lipid peroxidation. Upregulation of HNE in the plasma membrane was observed prior to the increase in intracellular H2 O2 . The amount of oxidized lipid present changed H2 O2 permeability and administration of oxidized lipid led to further cell death after treatment with H2 O2 . Expression levels of lipoxygenase ALOX genes (ie ALOX5, ALOX12, and ALOX15) were upregulated in ρ0 cells, as were expression levels of ALOX12 and ALOX15 proteins. ALOX5 protein was mainly distributed in the nucleus, while ALOX12 and ALOX15 proteins were distributed in the nucleus and the cytoplasm. Although expression of COX2 gene was upregulated, its protein expression did not increase. ALOX (especially ALOX15) may be involved in the sensitivity of cancer cells to treatment. These data offer promise for the development of novel anticancer agents by altering the oxidation state of the plasma membrane. Our results showed that lipid peroxidation status is important for H2 O2 sensitivity and that ALOX15 is involved in lipid peroxidation status.


Assuntos
Apoptose/efeitos dos fármacos , Permeabilidade da Membrana Celular/genética , DNA Mitocondrial/genética , Peróxido de Hidrogênio/administração & dosagem , Peroxidação de Lipídeos/genética , Neoplasias/patologia , Aldeídos/metabolismo , Araquidonato 15-Lipoxigenase/metabolismo , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos , Complexo de Proteínas da Cadeia de Transporte de Elétrons/genética , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/farmacocinética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Estresse Oxidativo/efeitos dos fármacos , Éteres Fosfolipídicos/administração & dosagem , Regulação para Cima
13.
Genes Genet Syst ; 94(2): 81-93, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-30930342

RESUMO

Apurinic/apyrimidinic (AP) sites are the most common form of cytotoxic DNA damage. Since AP sites inhibit DNA replication and transcription, repairing them is critical for cell growth. However, the significance of repairing AP sites during early embryonic development has not yet been clearly determined. Here, we focused on APEX1 from the ascidian Ciona intestinalis (CiApex1), a homolog of human AP endonuclease 1 (APEX1), and examined its role in early embryonic development. Recombinant CiApex1 protein complemented the drug sensitivities of an AP endonuclease-deficient Escherichia coli mutant, and exhibited Mg2+-dependent AP endonuclease activity, like human APEX1, in vitro. Next, the effects of abnormal AP site repair on embryonic development were investigated. Treatment with methyl methanesulfonate, which alkylates DNA bases and generates AP sites, induced abnormal embryonic development. This abnormal phenotype was also caused by treatment with methoxyamine, which inhibits AP endonuclease activity. Furthermore, we constructed dominant-negative CiApex1, which inhibits CiApex1 action, and found that its expression impaired embryonic growth. These results suggested that AP site repair is essential for embryonic development and CiApex1 plays an important role in AP site repair during early embryonic development in C. intestinalis.


Assuntos
Ciona intestinalis/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Desenvolvimento Embrionário/genética , Animais , Ciona intestinalis/embriologia , Ciona intestinalis/enzimologia , Reparo do DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Mutação
14.
Biol Open ; 8(3)2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30651235

RESUMO

hox genes are found as clusters in the genome in most bilaterians. The order of genes in the cluster is supposed to be correlated with the site of expression along the anterior-posterior body axis and the timing of expression during development, and these correlations are called spatial and temporal collinearity, respectively. Here we studied the expression dynamics of all hox genes of the diploid species Xenopus tropicalis in four Hox clusters (A-D) by analyzing high-temporal-resolution RNA-seq databases and the results showed that temporal collinearity is not supported, which is consistent with our previous data from allotetraploid X enopus laevis Because the temporal collinearity hypothesis implicitly assumes the collinear order of gene activation, not mRNA accumulation, we determined for the first time the timing of when new transcripts of hox genes are produced, by detecting pre-spliced RNA in whole embryos with reverse transcription and quantitative PCR (RT-qPCR) for all hoxa genes as well as several selected hoxb, hox c and hoxd genes. Our analyses showed that, coinciding with the RNA-seq results, hoxa genes started to be transcribed in a non-sequential order, and found that multiple genes start expression almost simultaneously or more posterior genes could be expressed earlier than anterior ones. This tendency was also found in hoxb and hoxc genes. These results suggest that temporal collinearity of hox genes is not held during early development of Xenopus.

15.
Data Brief ; 20: 402-410, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30175205

RESUMO

We present data about mitochondrial DNA (mtDNA) copy number and aquaporin (AQP) gene expression in clinically radioresistant (CRR), ρ0, and their parental cells from human cervical cancer and human tongue squamous cell carcinoma. In both ρ0 and CRR cells, the mtDNA copy number was lower than for the parental strain. In addition, the obtained data suggest an association between the gene expression levels of AQP (1, 3, 8, and 9) and the difference in hydrogen peroxide (H2O2) sensitivity between ρ0 and CRR cells. Here, the composition of cell culture medium differs between CRR and ρ0 cells. To compare the gene expression of AQPs between ρ0 and CRR cells, therefore, we showed the data as the ratio to that in their parental cells.

16.
Tumour Biol ; 40(9): 1010428318799250, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30192208

RESUMO

Radiation therapy is one of the choices to treat malignant tumors. In radiation therapy, existence of radiation-resistant cell is a major problem to overcome. We established clinically relevant radioresistant cells that had been obtained by exposing to 2 Gy/day X-rays for more than 30 days. These cells are resistant to 2 Gy/day X-ray exposure and anticancer agents. However, the underlying resistance mechanism remains unclear. We investigated the resistance of clinically relevant radioresistant cells to hydrogen peroxide (H2O2), confirming a degree of resistance. Neither catalase enzyme activity nor aquaporins appeared to be involved in H2O2 resistance. Mitochondrial DNA copy number, adenosine triphosphate (ATP) concentration, and plasma membrane potential were decreased. The timing of H2O2 intake was delayed and lipid peroxidation was decreased. Sensitivity of clinically relevant radioresistant cells to H2O2 was enhanced by 1-palmitoyl-2-(5'-oxo-valeroyl)-sn-glycero-3-phosphocholine administration. These results suggest that the membrane status is a major factor conferring H2O2 resistance in clinically relevant radioresistant cells, and we should further investigate how membrane status could be used to enhance the therapeutic effect on cancer.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células Escamosas/patologia , Peróxido de Hidrogênio/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Neoplasias Bucais/patologia , Oxidantes/farmacologia , Tolerância a Radiação/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/radioterapia , Catalase/metabolismo , Células HeLa , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/metabolismo , Neoplasias Bucais/radioterapia , Oxirredução , Células Tumorais Cultivadas , Raios X
17.
J Immunol ; 198(10): 4107-4114, 2017 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-28404634

RESUMO

How parasites recognize their definitive hosts is a mystery; however, parasitism is reportedly initiated by recognition of certain molecules on host surfaces. Fish ectoparasites make initial contact with their hosts at body surfaces, such as skin and gills, which are covered with mucosa that are similar to those of mammalian guts. Fish are among the most primitive vertebrates with immune systems that are equivalent to those in mammals, and they produce and secrete IgM into mucus. In this study, we showed that the monogenean parasite Heterobothrium okamotoi utilizes IgM to recognize its host, fugu Takifugu rubripes Oncomiracidia are infective larvae of H. okamotoi that shed their cilia and metamorphose into juveniles when exposed to purified d-mannose-binding fractions from fugu mucus. Using liquid chromatography-tandem mass spectrometry analysis, proteins contained in the fraction were identified as d-mannose-specific IgM with two d-mannose-binding lectins. However, although deciliation was significantly induced by IgM and was inhibited by d-mannose or a specific Ab against fugu IgM, other lectins had no effect, and IgM without d-mannose affinity induced deciliation to a limited degree. Subsequent immunofluorescent staining experiments showed that fugu d-mannose-specific IgM binds ciliated epidermal cells of oncomiracidium. These observations suggest that deciliation is triggered by binding of fugu IgM to cell surface Ags via Ag binding sites. Moreover, concentrations of d-mannose-binding IgM in gill mucus were sufficient to induce deciliation in vitro, indicating that H. okamotoi parasites initially use host Abs to colonize host gills.


Assuntos
Imunoglobulina M/imunologia , Manose/metabolismo , Membrana Mucosa/imunologia , Takifugu/imunologia , Takifugu/parasitologia , Trematódeos/fisiologia , Animais , Afinidade de Anticorpos , Sítios de Ligação de Anticorpos , Cromatografia Líquida , Cílios/fisiologia , Brânquias/parasitologia , Imunidade nas Mucosas , Imunoglobulina M/metabolismo , Larva/imunologia , Larva/fisiologia , Manose/imunologia , Membrana Mucosa/parasitologia , Espectrometria de Massas em Tandem
18.
Environ Pollut ; 224: 35-43, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28347471

RESUMO

The study of the DNA damage response in erythrocytes after γ-irradiation may provide evidence for its effectiveness as a biomarkers for genotoxic environmental stress. We previously reported various malformations in erythrocytes of medaka irradiated with10 Gy, but not in their micronuclei. In this study, we optimized an assay method for γ-H2AX and double strand breaks in erythrocytes of adult medaka fish after 15 Gy of γ-irradiation. The highest level of apoptosis and nuclear abnormalities, including in micronuclei, were recorded 4 h after γ-irradiation, as was the highest level of γ-H2AX foci in erythrocytes. These results suggest that recognition and repair processes occur as a response to DNA damage in erythrocytes in medaka.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA , Eritrócitos/efeitos da radiação , Raios gama , Histonas/efeitos da radiação , Oryzias/genética , Animais , Apoptose , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/efeitos da radiação , Feminino
19.
PLoS One ; 12(1): e0170006, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28107384

RESUMO

Nbs1 is one of the genes responsible for Nijmegen breakage syndrome, which is marked with high radiosensitivity. In human NBS1 (hNBS1), Q185E polymorphism is known as the factor to cancer risks, although its DSB repair defect has not been addressed. Here we investigated the genetic variations in medaka (Oryzias latipes) wild populations, and found 40 nonsynonymous single nucleotide polymorphisms (SNPs) in medaka nbs1 (olnbs1) gene within 5 inbred strains. A mutation to histidine in Q170 residue in olNbs1, which corresponds to Q185 residue of hNBS1, was widely distributed in the closed colonies derived from the eastern Korean population of medaka. Overexpression of H170 type olNbs1 in medaka cultured cell lines resulted in the increased accumulation of olNbs1 at laser-induced DSB sites. Autophosphorylation of DNA-dependent protein kinase at T2609 was suppressed after the γ-ray irradiation, which was followed by prolonged formation of γ-H2AX foci and delayed DSB repair. These findings suggested that the nonsynonymous SNP (Q170H) in olnbs1, which induced DSB repair defects, is specifically distributed in the eastern Korean population of medaka. Furthermore, examination using the variation within wild populations might provide a novel method to characterize a driving force to spread the disease risk alleles.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Reparo do DNA/fisiologia , Proteínas Nucleares/fisiologia , Oryzias/genética , Polimorfismo Genético , Sequência de Aminoácidos , Animais , Animais Selvagens , Proteínas de Ciclo Celular/química , Proteína Quinase Ativada por DNA/metabolismo , Modelos Moleculares , Proteínas Nucleares/química , Fosforilação , Homologia de Sequência de Aminoácidos
20.
Sci Rep ; 6: 28691, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27345436

RESUMO

Radiotherapy is widely used in cancer treatment. In addition to inducing effects in the irradiated area, irradiation may induce effects on tissues close to and distant from the irradiated area. Japanese medaka, Oryzias latipes, is a small teleost fish and a model organism for evaluating the environmental effects of radiation. In this study, we applied low-energy carbon-ion (26.7 MeV/u) irradiation to adult medaka to a depth of approximately 2.2 mm from the body surface using an irradiation system at the National Institutes for Quantum and Radiological Science and Technology. We histologically evaluated the systemic alterations induced by irradiation using serial sections of the whole body, and conducted a heart rate analysis. Tissues from the irradiated side showed signs of serious injury that corresponded with the radiation dose. A 3D reconstruction analysis of the kidney sections showed reductions in the kidney volume and blood cell mass along the irradiated area, reflecting the precise localization of the injuries caused by carbon-beam irradiation. Capillary aneurysms were observed in the gill in both ventrally and dorsally irradiated fish, suggesting systemic irradiation effects. The present study provides an in vivo model for further investigation of the effects of irradiation beyond the locally irradiated area.


Assuntos
Radioterapia com Íons Pesados/efeitos adversos , Rim/patologia , Miocárdio/patologia , Oryzias/metabolismo , Lesões Experimentais por Radiação/patologia , Animais , Rim/metabolismo , Miocárdio/metabolismo , Lesões Experimentais por Radiação/metabolismo
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