• The Korean Journal of Physiology and Pharmacology
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• v.22 no.5
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• pp.513-523
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• 2018

The tumor microenvironment greatly influences cancer cell characteristics, and acidic extracellular pH has been implicated as an essential factor in tumor malignancy and the induction of drug resistance. Here, we examined the characteristics of gastric carcinoma (GC) cells under conditions of extracellular acidity and attempted to identify a means of enhancing treatment efficacy. Acidic conditions caused several changes in GC cells adversely affecting chemotherapeutic treatment. Extracellular acidity did inhibit GC cell growth by inducing cell cycle arrest, but did not induce cell death at pH values down to 6.2, which was consistent with down-regulated cyclin D1 and up-regulated p21 mRNA expression. Additionally, an acidic environment altered the expression of atg5, HSPA1B, collagen XIII, collagen XXAI, slug, snail, and zeb1 genes which are related to regulation of cell resistance to cytotoxicity and malignancy, and as expected, resulted in increased resistance of cells to multiple chemotherapeutic drugs including etoposide, doxorubicin, daunorubicin, cisplatin, oxaliplatin and 5-FU. Interestingly, however, acidic environment dramatically sensitized GC cells to apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Consistently, the acidity at pH 6.5 increased mRNA levels of DR4 and DR5 genes, and also elevated protein expression of both death receptors as detected by immunoblotting. Gene silencing analysis showed that of these two receptors, the major role in this effect was played by DR5. Therefore, these results suggest that extracellular acidity can sensitize TRAIL-mediated apoptosis at least partially via DR5 in GCs while it confers resistance to various type of chemotherapeutic drugs.

• Molecular Medicine Reports
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• v.20 no.4
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• pp.3933-3941
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• 2019

The microbiome has recently attracted research interest in a variety of subjects, including cancer. In the present study, it was determined that reinforced clostridium media (RC M) for microbiome culture, exerts antitumor effects on renal cell carcinoma cells when compared to the microbiome 'X'. The antitumor effects of RC M were investigated for all ingredients of RC M, and the results revealed that yeast extract could be a candidate for the ingredient driving this phenomenon. Further experiments including MTT assay, cell counting, cell death analysis, cell cycle analysis and western blotting were conducted with yeast extract on renal cell carcinoma cells (Caki-1 and Caki-2) and normal human proximal tubular cells (HK-2). As a result, yeast extract exhibited dose-dependent antitumor effects on Caki-1 and Caki-2, but only slight effects on HK-2. In addition, yeast extract only exhibited slight effects on necrosis, autophagy, or apoptosis of Caki-1 and Caki-2. Yeast extract produced cell cycle arrest with an increased G0/G1 fraction and a decreased S fraction, and this was considered to be related to the decreased cyclin D1. Although yeast extract treatment increased anti-oxidant activities, the antitumor effects of yeast extract were also related to iron metabolism, based on the decreased transferrin receptor and increased ferritin. In addition, decreased GPX4 may be related to iron-dependent cell death, particularly in Caki-2. These results revealed that yeast extract may inhibit proliferation of renal cell carcinoma cells by regulating iron metabolism. Since an increased iron requirement is a classic phenomenon of cancer cells, yeast extract may be a candidate for adjuvant treatment of renal cell carcinoma.

• The Journal of Internal Korean Medicine
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• v.31 no.3
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• pp.586-599
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• 2010

Objective : The water extract of Yukgunja-tang(YGJT) has been traditionally used in treatment of qi deficiency and phlegm in Oriental medicine. However, little is known about the mechanism by which YGJT protects neuronal cells from injury damages. Therefore, this study was designed to evaluate the protective effects of YGJT on C6 glial cells by glutamate-induced cell death. Methods : The present study describes glutamate, which is known as an excitatory neurotransmitter, related with oxidative damages, and YGJT, which shows protective effects against glutamate-induced C6 glial cell death. One of the main mediators of glutamate-induced cytotoxicity was known on the generation of reactive oxygen species(ROS) via activation of NADPH oxidase (NOX). The protective effects of antioxidant(NAC) and NOX inhibitor(apocynin) on the glutamate-induced C6 glial cells were determined by a MTT reduction assay. Result : YGJT inhibited glutamate-induced ROS generation via inhibition of NOX expression on glutamate-stimulated C6 glial cells. Furthermore, YGJT attenuated glutamate-induced caspase activation. These results suggest that YGJT could be a new potential candidate against glutamate-induced oxidative stress and cell death. Conclusion : These findings indicate that in C6 glial cells, ROS plays an important role of glutamate-induced cell death and that YGJT may prevent cell death from glutamate-induced cell death by inhibiting the ROS generation.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8405-8408
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• 2014

Background: This analysis was conducted to evaluate the efficacy and safety of temozolomide based chemotherapy in treating patients with glioma. Methods: Clinical studies evaluating the efficacy and safety of temozolomide based regimens for patients with glioma were identified using a predefined search strategy. Pooled response rates (RRs) were calculated. Results: In temozolomide based regimens, 5 clinical studies including 152 patients with advanced glioma were considered eligible for inclusion. Four clinical studies included temozolomide. Systematic analysis suggested that, in all patients, pooled CR was 21% (32/152), and PR was 21% (32/152). Grade 3/4 toxicity included neutropenia, thrombocytopenia, and anemia. No grade 3 or 4 renal or liver toxicity was observed. No treatment related death occurred with temozolomide based treatment. Conclusion: This systematic analysis suggests that temozolomide based regimens are associated with mild response rate and acceptable toxicity for treatment of glioma patients.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.138-143
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• 2023

Liver fibrosis is caused by metabolic problems such as cholestasis, genetic problems, or viral infections. Inhibiting hepatic stellate cell (HSC) activation or inducing selective apoptosis of activated HSCs is used as a treatment strategy for liver fibrosis. It has been reported that when HSCs are activated, their apoptosis sensitivity to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is enhanced because the expression of death receptor 5 is elevated. Finding a natural compound that can enhance the apoptotic effect of TRAIL on HSCs is a necessary strategy for liver fibrosis treatment. It was confirmed here that mangosteen-derived gartanin increased the effect of TRAIL-induced apoptosis by increasing the expression of DR5 in a p38-dependent manner in the hepatic stellate cell line LX-2. Combined treatment with gartanin and TRAIL accelerated DNA cleavage through caspase-3 activation and enhanced antifibrotic effects in LX-2 cells.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.64.1-64
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• 2003

Inoculation of primary pepper leaves with an avirulent strain of Xanthomonas campestris pv. vesicatoria induced systemic acquired resistance (SAR) in secondary leaves. This SAR response was accompanied by the systemic expression of defense-related genes, a systemic microoxidative burst generating H2O2, and the systemic induction of ion-leakage and callose deposition in the non-inoculated, secondary leaves. Some defense-related genes encoding PR-1, chitinase, peroxidase, PR10, thionin, defensin and zinc-finger protein were distiilctly induced in the systemic leaves. The systemically striking accumulation of H$_2$O$_2$and strong increase in peroxidase activity in pepper was suggested to contribute to the triggering of cell death In the systemic micro-HRs, leading to the induction of SAR. Treatment of non-inoculated, secondary leaves with diphenylene iodinium (DPI), an inhibitor of the oxidative burst, substantially reduced the induction of some defense-related genes and subsequently SAR.

• Korean Journal of Psychosomatic Medicine
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• v.4 no.2
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• pp.215-225
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• 1996

We studied the factors that would affect the severity of psychiatric symptoms of the Sampoong accident survivors. In this study, the analyzed factors are sex, age, marital status, educational level, loss of consciousness, witness of death, death of related person, duration until the rescue, duration of hospitalization, and psychiatric treatment after the accident. Although our study has some limitations, we found some factors that affect the severity of psychiatric symptoms after the severe traumatic accident.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.sup1
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• pp.116-120
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• 2008

Prostate cancer is the second leading cause of cancer death of men in western countries and the death related to this disease in Korea is also getting increased. Although anatomic imaging tools such as transrectal US or MRI have been playing a great role in detection of primary prostate lesion, the evaluation of regional lymph node or distant organ metastasis using these modalities is not successful. $^{18}F-FDG-PET$ scan is emerging diagnostic tool for various malignancies. Considering the usual characteristics of prostate cancer such as slow growing and osteoblastic metastasis, the application of FDG PET scan to this disease might be limited. However, in advanced prostate cancer refractory to chemotherapy, FDG PET scan show strong FDG uptake and SUV changes in serial PET scan can be a good indicator of treatment response. Although FDG PET can be useful only in limited cases of prostate cancer, its indication can be widened in future owing to rapid technical improvement and accumulated experiences in this field.

• YAKHAK HOEJI
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• v.56 no.1
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• pp.35-41
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• 2012

In this study, we examined the effect of luteolin to enhance TRAIL-induced anticancer effect in SK-Hep1 cells. We found that combined use of TRAIL with luteolin markedly enhanced the cytotoxicity compared to either agent alone by inducing apoptosis. Furthermore, combined treatment of TRAIL with luteolin significantly induced activation of death receptor pathway-related proteins as well as PARP-cleavage and activation of effector caspases. Also, our result indicated that upregulation of DR4 and DR5 by luteolin combination may contribute to enhanced susceptibility of SK-Hep1 cells to TRAIL.

• Journal of Trauma and Injury
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• v.33 no.4
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• pp.269-274
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• 2020

Open pelvic fractures are rare, but pose challenges for trauma surgeons due to their high morbidity and mortality. Generally, early death results from uncontrolled exsanguination and late death is related to pelvic sepsis. Therefore, management of these injuries should prioritize hemostasis and contamination control starting in the initial phase of treatment. We report two cases of unstable open pelvic fractures with perineal wounds that were managed successfully.