• Journal of Life Science
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• v.26 no.10
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• pp.1182-1188
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• 2016

Membrane-associated guanylate kinase inverted-3 (MAGI-3) is a member of the family of membrane-associated guanylate kinases (MAGUKs). MAGI-3 modulates the kinase activity of protein kinase B (PKB)/AKT through interactions with phosphatase and tensin homolog (PTEN)/MMAC. Coxsackievirus B3 (CVB3) is a common causative agent of acute myocarditis and chronic dilated cardiomyopathy. Activation of AKT and extracellular signal-regulated kinases 1/2 (ERK1/2) is essential for CVB3 replication, but the relation between MAGI-3 signaling and CVB3 replication is not well understood. This study investigated the role of MAGI-3 in CVB3 infection and replication. MAGI-3 was overexpressed in HeLa cells by polyethylenimine (PEI) transfection. To optimize the transfection conditions, different ratios of plasmid DNA to PEI concentrations were used. MAGI-3 and empty plasmid DNA were transfected into the HeLa cells. MAGI-3 overexpression alone was not sufficient to efficiently activate AKT. However, expression of the CVB3 capsid protein VP1 dramatically increased in the HeLa cells overexpressing MAGI-3 24 h after CVB3 infection. In addition, the activities of AKT and ERK were significantly induced in the CVB3-infected MAGI-3 cells overexpressing HeLa. These results demonstrate that MAGI-3 expression upregulates CVB3 replication through AKT and ERK signaling activation. MAGI-3 may be an important target to control CVB3 replication.

• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.255-259
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• 2005

IgE-dependent histamine-releasing factor (HRF) is found extracellularly to regulate the degranulation process of histamine in mast cells and basophils and known to play a predominant role in the pathogenesis of chronic allergic disease. HRF has been also identified in the intracellular region of the cell. Previously, we reported that HRF interacts with the 3rd cytoplasmic domain of the alpha subunit of Na,K-ATPase. To understand the molecular mechanism of the regulation of Na, K-ATPase activity by HRF, we investigated the interaction between HRF and TPI since TPI was obtained as HRF-interacting protein in HeLa cDNA library, using yeast two hybrid screening. Domain mapping study of the interaction between HRF and TPI revealed that the C-terminal region of the residue 156-249 of TPI is involved in the interaction with HRF. The interaction between HRF and TPI was confirmed by immunoprecipitation from HeLa cell extracts. Our results suggest that TPI is a HRF-binding protein and the interaction between HRF and TPI nay thus affect Na, K-ATPase activity.

• Korean Journal of Pharmacognosy
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• v.35 no.3 s.138
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• pp.250-254
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• 2004

Helicobacter pylori (H. pyroli) infection it associated with type B gastritis, peptic uler disease, and gastric cancer. The vacuolation of cells induced by H. pylori is thought to be essential for the initiation and maintenance of gastric infection. The roles of H. pylori cytotoxin, urease, and ammonia in the vacuolation of HeLa cells were determined. H. pylori toxin induced vacuolation of HeLa cells. Korean and Japanese radishes significantly prevented the vacuolation of HeLa cells induced by H. pylori toxin. The urease activity in vacuolated cells was also decreased with Korean and Japanese radishes. H. Pylori toxin-induced vacuolation was inhibited by vacuolar type ATPase inhibitors (bafilomycin and N-ethylmaleimide). However, further investigation is required to determine the mechanisms of radish for the inhibition of vacuole formation of eukaryotic cells in response to the H. pylori toxin.

• The Korean Journal of Zoology
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• v.11 no.3
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• pp.75-82
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• 1968

The effects of x-irradiation on the utilization of glucose, succinate, citrate and $\\alpha$-ketoglutarate, on the response of the cell metabolism to $NaN_3$ and DNP, and on the uptake of lysine in the presence or absence of the metabolitesor the inhibitors were studied using HeLa cells and the results are summarized as follows: 1. 200r of x-irradiation had no immediate effect on the oxygen consumption of cells. 2. The oxygen consumption was greatly stimulated by succinate, $\\alpha$-ketoglutarate and citraed and in decreasing order and x-irradiation caused no remarkable change in this order. 3. The respiratory response of the cell to the metabolic inhibitors seems to be altered by x-irradiation. 4. The initial rate of the uptake of lysine was markedly retarded and the accumulation of lysine in the cell was decreased by irradiation. 5. Glucose increased the lysine uptake whereas succinate had no effect and citrate and $\\alpha$-ketoglutarate reduced the absorption. X-irradiation did not alter this tendency. 6. The inhibitory effects of $NaN_3$ and DNP on the lysine uptake were quite different from those seen in the oxygen consumption.

• Journal of Nutrition and Health
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• v.35 no.4
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• pp.439-445
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• 2002

This study was undertaken to investigate the inhibitory effect of prunus fume extracts on the growth of Hep G2 and HeLa cells. Prunus mums was extracted using the following solvents hexane, chloroform, ethylacetate, methanol, and hot water. The effect on the growth of each cancer cell line was examined by MTT (3-[4, 5-dimethylthiaeol-2-yl)-2,5-diphenyl tetrazolium bromide) assay, cytotoxicity testing, and microscopic observation. The ethylacetate extracts of Prunus muse at the concentration of 250 $\mu\textrm{g}$/ml exhibited the greatest inhibitory effect on the growth of Hep G2 in the MW assay. In cytotoxicity testing, the treatment of the Hep G2 cells with ethylacetate extracts (1000 $\mu\textrm{g}$/ml for 72 hrs) destroyed 75% of the cells, and morphological changes were also observed. futhermore, the hexane extracts of Prunes muse at the concentration of 250 $\mu\textrm{g}$/ml exhibited the greatest inhibitory effect on the growth of HeLa cells in the MTT assay. The treatment of the HeLa cells with the hexane extracts (1000 $\mu\textrm{g}$/ml for 72 hrs) resulted in the destruction of 68% of the cells. Fibroblasts were not affected by either ethylacetate or hexane extracts of prunus muse.

• Korean Journal of Pharmacognosy
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• v.25 no.2
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• pp.144-152
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• 1994

The combined effects of Ulmi Cortex and some anti-cancer drugs on the proliferation of HeLa cells, Hep G2 cells and S 180 cells were estimated by MTT calorimetric assay. The n-BuOH fraction(UBF) of Ulmi Cortex inhibited the proliferation of HeLa cell at $10^{-3}\;g/ml$, Hep G2 cell at $10^{-5}\;g/ml$ and S 180 cell at $10^{-3}\;g/ml$. The inhibitory effects of mitomycin C(MMC), cisplatin(CPT) and 5-fluorouracil (5-FU), respectively, on Hep G2 cell was increased by the UBF. The UBF did not influence the proliferation of Balb/c 3T3 cells at concentrations of $10^{-6}$ to $10^{-4}\;g/ml$, but increased the proliferation of T cells at concentrations of $10^{-5}$ to $10^{-4}\;g/ml$. The UBF did not influence the number of leukocyte, and on the thymus weight of mice. The UBF increased the number of total-peritoreal cells of mice. In conclusion, the results suggest that the UBF have anti-cancer activity without the side effect, such as leukopenia and immunosuppresion, and increase the inhibitory activity of the anti-cancer drugs on Hep G2 cells.

• Radiation Oncology Journal
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• v.16 no.2
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• pp.99-106
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• 1998

Purpose : We conducted clonogenic assay using human cancer cell lines (MKN-45, PC-14, Y-79, HeLa) to investigate a correlation between the parameters of radiosensitivity. Materials and Methods : Human cancer cell lines were irradiated with single doses of 1, 2, 3, 5, 7 and 10Gy for the study of radiosensitivity and subrethal damage repair capacity was assessed with two fractions of 5Gy separated with a time interval of 0, 1, 2, 3, 4, 6 and 24 hours. Surviving fraction was assessed with clonogenic assay using $Sperman-H\"{a}rbor$ method and mathematical analysis of survival curves was done with linear-quadratic (LQ) , multitarget-single hit(MS) model and mean inactivation dose$(\v{D})$. Results : Surviving fractions at 2Gy(SF2) were variable among the cell lines, ranged from 0.174 to 0.85 The SF2 of Y-79 was lowest and that of PC-14 was highest(p<0.05, t-test). LQ model analysis showed that the values of $\alpha$ for Y-79, MKN-45, HeLa and PC-14 were 0.603, 0.356, 0.275 and 0.102 respectively, and those of $\beta$ were 0.005, 0.016, 0.025 and 0.027 respectively. Fitting to MS model showed that the values of Do for Y-79. MKN-45, HeLa and PC-14 were 1.59. 1.84. 1.88 and 2.52 respectively, and those of n were 0.97, 1.46, 1.52 and 1 69 respectively. The $\v{D}s$ calculated by Gauss-Laguerre method were 1.62, 2.37, 2,01 and 3.95 respectively So the SF2 was significantly correlated with $\alpha$, Do and $\v{D}$. Their Pearson correlation coefficiencics were -0.953 and 0,993. 0.999 respectively(p<0.05). Sublethal damage repair was saturated around 4 hours and recovery ratios (RR) at plateau phase ranged from 2 to 3.79. But RR was not correlated with SF2, ${\alpha}$, ${\beta}$, Do, $\v{D}$. Conclusion : The intrinsic radiosensitivity was very different among the tested human cell lines. Y-79 was the most sensitive and PC-l4 was the least sensitive. SF2 was well correlated with ${\alpha}$, Do, and $\v{D}$. RR was high for MKN-45 and HeLa but had nothing to do with radiosensitivity parameters. These basic parameters can be used as baseline data for various in vitro radiobiological experiments.

• BMB Reports
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• v.41 no.3
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• pp.230-235
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• 2008

LRP15 is a novel gene cloned from lymphocytic cells, and its function is still unknown. Bioinformatic data showed that LRP15 might be regulated by DNA methylation and had an important role in DNA repair. In this study, we investigate whether the expression of LRP15 is regulated by DNA methylation, and whether overexpression of LRP15 increases efficiency of DNA repair of UV-induced DNA damage in HeLa cells. The results showed (1) the promoter of LRP15 was hypermethylated in HeLa cells, resulting a silence of its expression. Gene expression was restored by a demethylating agent, 5-aza-2'-deoxycytidine, but not by a histone deacetylase inhibitor, trichostatin A; (2) overexpression of LRP15 inhibited HeLa cell proliferation, and the numbers of cells in the G2/M phase of the cell cycle in cells transfected with LRP15 increased about 10% compared with controls; (3) cyclin B1 level was much lower in cells overexpressing LRP15 than in control cells; and (4) after exposure to UV radiation, the LRP15-positive cells showed shorter comet tails compared with the LRP15-negative cells. From these results we conclude that the expression of LRP15 is controlled by methylation in its promoter in HeLa cells, and LRP15 confers resistance to UV damage and accelerates the DNA repair rate.

• Korean Journal of Pharmacognosy
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• v.31 no.1
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• pp.7-15
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• 2000

Glycyrrhizae Radix aqua-acupuncture solution (GRAS) and Glycyrrhizae Radix water-extracted solution (GRWS) were prepared and tested for organ toxicities, antitumor activities, and immunomodulatory effects. The organ-toxicity of GRAS to male ICR mice was studied by the measurements of glutamic oxaloacetic transaminase (GOT), glutamic pyruvate transaminase (GPT), lactate dehydrogenase (LDH), and alkaline phosphatase (ALP-s) activities after injection of GRAS for 7 days. The activities of GOT, GPT, LDH, ALP-s were decreased with GRAS. It was shown to possess considerable toxicity toward various tumor cell lines. Concentration of GRAS at 1.5g/ml and 3g/ml resulted in more than 80% inhibition of growth in Ehrlich ascites tumor cells (EATC), Hepa1c1c7, and HeLa cells. Toxicity of GRAS to A549 revealed that 68% inhibition of growth. GRWS at the concentration of 3g/ml showed more than 80% inhibition of growth with EATC, Hepalclc7, A549 and HeLa. In morphological study, the number of cells were decreased, and the shape of cells was round-form in EATC, Hepalclc7, A549 and HeLa cells with GRAS. Administration of GRAS inhibited the growth of EATC in vivo. Mice given EATC at 1.5g/ml or 0.3g/ml GRAS had 16.7% to 50% survival after 21 days. GRAS increased the proliferation of T and B cells and the cytolytic activity of purified T cell. The biosyntheses of nucleic acid and protein of EATC, Hepalclc7, A549 and HeLa cells were inhibited by GRAS.

• Toxicological Research
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• v.33 no.3
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• pp.211-218
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• 2017

Cytochrome P450 1B1 (CYP1B1) acts as a hydroxylase for estrogen and activates potential carcinogens. Moreover, its expression in tumor tissues is much higher than that in normal tissues. Despite this association between CYP1B1 and cancer, the detailed molecular mechanism of CYP1B1 on cancer progression in HeLa cells remains unknown. Previous reports indicated that the mRNA expression level of Herc5, an E3 ligase for ISGylation, is promoted by CYP1B1 suppression using specific small interfering RNA, and that ISGylation may be involved in ubiquitination related to ${\beta}-catenin$ degradation. With this background, we investigated the relationships among CYP1B1, Herc5, and ${\beta}-catenin$. RT-PCR and western blot analyses showed that CYP1B1 overexpression induced and CYP1B1 inhibition reduced, respectively, the expression of $Wnt/{\beta}-catenin$ signaling target genes including ${\beta}-catenin$ and cyclin D1. Moreover, HeLa cells were treated with the CYP1B1 inducer $7,12-dimethylbenz[{\alpha}]anthracene$ (DMBA) or the CYP1B1 specific inhibitor, tetramethoxystilbene (TMS) and consequently DMBA increased and TMS decreased ${\beta}-catenin$ and cyclin D1 expression, respectively. To determine the correlation between CYP1B1 expression and ISGylation, the expression of ISG15, a ubiquitin-like protein, was detected following CYP1B1 regulation, which revealed that CYP1B1 may inhibit ISGylation through suppression of ISG15 expression. In addition, the mRNA and protein expression levels of Herc5 were strongly suppressed by CYP1B1. Finally, an immunoprecipitation assay revealed a direct physical interaction between Herc5 and ${\beta}-catenin$ in HeLa cells. In conclusion, these data suggest that CYP1B1 may activate $Wnt/{\beta}-catenin$ signaling through stabilization of ${\beta}-catenin$ protein from Herc5-mediated ISGylation for proteosomal degradation.