• Clinical and Experimental Pediatrics
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• v.52 no.2
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• pp.213-219
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• 2009

Purpose:Iron is a critical nutritional element that is essential for a variety of important biological processes, including cell growth and differentiation, electron transfer reactions, and oxygen transport, activation, and detoxification. Iron is also required for neoplastic cell growth due to its catalytic effects on the formation of hydroxyl radicals, suppression of host defense cell activities, and promotion of cancer cell multiplication. Chronic transfusion-dependent patients receiving chemotherapy may have iron overload, which requires iron-chelating therapy. We performed this study to demonstrate whether the iron chelating agent deferoxamine induces apoptosis in Saos-2 osteosarcoma cells, and to investigate the underlying apoptotic mechanism. Methods:To analyze the apoptotic effects of an iron chelator, cultured Saos-2 cells were treated with deferoxamine. We analyzed cell survival by trypan blue and crystal violet analysis, apoptosis by nuclear condensation, DNA fragmentation, and cell cycle analysis, and the expression of apoptotic related proteins by Western immunoblot analysis. Results:Deferoxamine inhibited the growth of Saos-2 cell in a time- and dose-dependent manner. The major mechanism for growth inhibition with the deferoxamine treatment was by the induction of apoptosis, which was supported by nuclear staining, DNA fragmentation analysis, and flow cytometric analysis. Furthermore, bcl-2 expression decreased, while bax, caspase-3, caspase-9, and PARP expression increased in Saos-2 cells treated with deferoxamine. Conclusion:These results demonstrated that the iron chelating agent deferoxamine induced growth inhibition and mitochondrial-dependent apoptosis in osteosarcoma Saos-2 cells, suggesting that iron chelating agents used in controlling neoplastic cell fate can be potentially developed as an adjuvant agent enhancing the anti-tumor effect for the treatment of osteosarcoma.

• Tuberculosis and Respiratory Diseases
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• v.57 no.2
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• pp.160-168
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• 2004

Background : The role of second-line chemotherapy in the treatment of advanced non-small cell lung cancer (NSCLC) is known to be limited. Recently, ZD1839, the small molecule epidermal growth factor receptor-tyrosine kinase inhibitor, has been developed and has shown anti-tumor activity in patients with solid malignant tumors including lung cancer. We evaluated the response rate and toxicities of ZD1839 in patients with advanced NSCLC which has progressed after previous chemotherapy. Patients and Methods : We examined 83 patients with advanced NSCLC treated with ZD1839 for more than 1 month in Korea Cancer Center Hospital during the period from January 2002 to September 2003. All the patients were enrolled in the international expanded access program (EAP) with ZD1839 by AstraZeneca. The administered dose of ZD1839 was 250 mg once daily. Chest radiography and laboratory tests were followed-up. We evaluated the response rate, median survival, and toxicity after treatment. Results : Median age of the patients was 59 years (range 33-76). The most predominant cell type was adenocarcinoma and the most stage of the patients was IV. ECOG performance status was as follows; grade 0-1 in 10, grade 2 in 42, and grade 3 in 31 patients. Partial response was achieved in 12 patients (14.5%). Median overall survival was 9.2 (range 1.3-21.6+) months and median time to progression was 3.1 (range 1-21.2+) months. The most common adverse effect of ZD1839 was skin eruption which developed in 25 patients (25.8%). Significantly higher response rate and survival was found in patients with adenocarcinoma or good performance status. Conclusion : ZD1839 showed modest activity and tolerable toxicity in the treatment for patients with NSCLC which has progressed after previous chemotherapy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.929-937
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• 2016

The purpose of this study was to investigate the effect of Acanthopanax senticosus extract (ASE) (ethanol : DW=1:1, v/v) on inhibition of type 2 diabetes using an OLETF rat model via regulation of HbA1c and AGEs levels. Supplementation with ASE 0.1% and 0.5% effectively lowered levels of glucose, insulin, oral glucose tolerance test, and Homa-insulin resistance, suggesting reduced insulin resistance. Blood levels of HbA1c and AGEs were significantly reduced in a dose-dependent manner. As oxidative stress plays a key role in accelerating production of HbA1c and AGEs, which worsen symptoms of type 2 diabetes, levels of malonaldehyde and pro-inflammatory cytokines were measured. Lipid peroxidation in both blood and liver tissues was significantly reduced, and induction of pro-inflammatory cytokines interleukin-${\beta}$ and tumor necrosis factor-${\alpha}$, which elevate production of HbA1c and AGEs, was inhibited (P<0.05). To evaluate the possible cellular events after AGEs receptor activation, genetic expression of protein kinase C (PKC)-${\delta}$ and transforming growth factor (TGF)-${\beta}$ was measured by real-time polymerase chain reaction. Supplementation with both ASE 0.1% and 0.5% significantly inhibited mRNA expression of PKC-${\delta}$ and TGF-${\beta}$, indicating that ASE may have beneficial effects on preventing insulin-resistant cells or tissues from progressing to diabetic complications. Taken together, ASE has potential to improve type 2 diabetes by inhibiting insulin resistance and protein glycosylation, including production of HbA1c and AGEs. Anti-oxidative activities of ASE are a main requisite for reducing production of HbA1c and AGEs and are also related to regulation of the PKC signaling pathway, resulting in suppression of TGF-${\beta}$, which increases synthesis of collagen, prostaglandin, and disease-related proteins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.664-672
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• 2015

In order to develop new immuno-stimulating ingredients from mature leaves of green tea, crude polysaccharides were isolated from pectinase digests of tea leaves (green tea enzyme digestion, GTE-0), after which their immuno-stimulating activities and chemical properties were examined. GTE-0 mainly contained neutral sugars (54.9%) such as glucose (14.2%), arabinose (12.2%), rhamnose (11.1%), and galacturonic acid (45.1%), which are characteristic of pectic polysaccharides. The anti-complementary activity of GTE-0 was similar to that of polysaccharide K (used as positive control). Number of morphologically activated macrophages was significantly increased in the GTE-0-treated group. GTE-0 significantly augmented $H_2O_2$ and reactive oxygen species production by murine peritoneal macrophage cells in a dose-dependent manner, whereas production of nitric oxide showed the highest activity at a dose of $100{\mu}g/mL$ among all tested concentrations. Murine peritoneal macrophages stimulated with GTE-0 showed enhanced production of various cytokines such as interleukin (IL)-6, IL-12, and tumor necrosis factors-${\alpha}$ in a dose-dependent manner. Further, GTE-0 induced higher phagocytic activity in a dose-dependent manner. In ex vivo assay for cytolytic activity of murine peritoneal macrophages, GTE-0-treated group showed significantly higher activity compared to the untreated group at an effector-to-target cell ratio of 20. The above results lead us to conclude that polysaccharides from leaves of green tea have a potent immuno-stimulating effect on murine peritoneal macrophage cells.

• Tuberculosis and Respiratory Diseases
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• v.62 no.1
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• pp.33-42
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• 2007

Background: Heme oxygenase-1 (HO-1) is known to modulates the cellular functions, including cell proliferation and apoptosis. It is known that a high level of HO-1 expression is found in many tumors, and HO-1 plays an important role in rapid tumor growth on account of its antioxidant and antiapoptotic effects. Cisplatin is a widely used anti-cancer agent for the treatment of lung cancer. However, the development of resistance to cisplatin is a major obstacle to its use in clinical treatment. We previously demonstrated that inhibiting HO-1 expression through the transcriptional activation of Nrf2 induces apoptosis in A549 cells. The aim of this study was to determine of the inhibiting HO-1 enhance the chemosensitivity of A549 cells to cisplatin. Materials and Methods: The human lung cancer cell line, A549, was treated cisplatin, and the cell viability was measured by a MTT assay. The change in HO-1, Nrf2, and MAPK expression after the cisplatin treatment was examined by Western blotting. HO-1 inhibition was suppressed by ZnPP, which is a specific pharmacologic inhibitor of HO activity, and small interfering RNA (siRNA). Flow cytometry analysis and Western blot were performed in to determine the level of apoptosis. The level of hydrogen peroxide ($H_2O_2$) generation was monitored fluoimetrically using 2',7'-dichlorofluorescein diacetate. Results: The A549 cells showed more resistance to the cisplatin treatment than the other cell lines examined, whereas cisplatin increased the expression of HO-1 and Nrf2, as well as the phosphorylation of MAPK in a time-dependent fashion. Inhibitors of the MAPK pathway blocked the induction of HO-1 and Nrf2 by the cisplatin treatment in A549 cells. In addition, the cisplatin-treated A549 cells transfected with dither the HO-1 small interfering RNA (siRNA) or ZnPP, specific HO-1 inhibitor, showed in a more significantly decrease in viability than the cisplatin-only-treated group. The combination treatment of ZnPP and cisplatin caused in a marked increase in the ROS generation and a decrease in the HO-1 expression. Conclusion: Cisplatin increases the expression of HO-1, probably through the MAPK-Nrf2 pathway, and the inhibition of HO-1 enhances the chemosensitivity of A549 cells to cisplatin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.619-624
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• 2011

Tea extract (TE) has been shown to have anti-tumor properties in a wide variety of experimental systems. We evaluated green tea extract (GTE) as a biochemical modulator for the antitumor activity of cisplatin and doxorubicin in the treatment of human lung cancer A549 cells. Cells were grown in RPMI-1640 medium supplemented with 10% (v/v) heat-inactivated fetal bovine serum and two antibiotics (100 units/mL penicillin and $100\;{\mu}g$/mL streptomycin). Two types of TE, epigallocatechin galate (EGCG) and GTE, were used in this experiment. The cells were seeded at $1{\times}10^4$ cells/well in the RPMI-1640 media with or without TE ($100\;{\mu}g$/mL) and then treated with different concentrations of doxorubicin ($0{\sim}14\;{\mu}g$/mL) or cisplatin ($0{\sim}35\;{\mu}g$/mL). After incubation in 5% $CO_2$ at $37^{\circ}C$ for 24 hr, cell viability was determined with a MTT assay. We used a Western blot to detect the influence of EGCG and GTE on the expression of p53 and caspase-3 genes in the A549 cells. A549 cell viability decreased to 15% with a $10\;{\mu}g$/mL concentration of cisplatin, and to 21% with a $8\;{\mu}g$/mL concentration of doxorubicin, as measured with the MTT assay. However, pre-treatment of the cells with EGCG ($100\;{\mu}g$/mL) or GTE ($100\;{\mu}g$/mL) resulted in decreased cell viability with $6\;{\mu}g$/mL of cisplatin and $4\;{\mu}g$/mL of doxorubicin. There was no apparent change in cell viability between EGCG or GTE administration in cisplatin- or doxorubicin-induced cytotoxicity in A549 cells. The levels of p53 and caspase-3 in the A549 cells increased with both EGCG and GTE treatment. We found that GTE could potentially affect cisplatin- or doxorubicin-induced cytotoxicity of A549 cells, which may be useful in the chemotreatment of cancer.

• Journal of Life Science
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• v.29 no.4
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• pp.484-491
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• 2019

Proanthocyanidins are naturally occurring polyphenolic compounds abundant in many vegetables, plant skins (rind/bark), seeds, flowers, fruits, and nuts. Numerous in vitro and in vivo studies have demonstrated myriad effects potentially beneficial to human health, such as antioxidation, immunomodulation, DNA repair, and antitumor activity. Among immune cells, macrophages are crucial players in a variety of inflammatory responses to environmental conditions. However, it has been widely reported that macrophages cause chronic inflammation and are involved in a variety of diseases, such as obesity, diabetes, metabolic syndrome, and cancer. In this study, we report the suppressive effect of proanthocyanidins via the heme oxygenase-1 (HO-1)-related system, on the immune response of the LPS-stimulated mouse macrophage cell line RAW264.7. Increased HO-1 expression at mRNA and protein levels were found in proanthocyanidins-treated RAW264.7 cells. Further, proanthocyanidins enhanced nuclear factor-erythroid 2-related factor 2 translocation into the nucleus. RAW264.7 cells were treated with lipopolysaccharide (LPS) with or without proanthocyanidins, and inflammatory mediator expression levels were assessed. Proanthocyanidins treatment resulted in the attenuation of nitric oxide production and inducible nitric oxide synthase expression in LPS-stimulated RAW264.7 cells. In addition, mRNA and protein expression of proinflammatory cytokines, such as tumor necrosis factor-${\alpha}$ and interleukin-6, was inhibited by proanthocyanidins treatment in LPS-stimulated RAW264.7 cells. These findings support proanthocyanidins as a promising anti-inflammatory agent.

• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.382-392
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• 2003

Purpose: Uptakes of Tc-99m MIBI (MIBI) and Tc-99m tetrofosmin (tetrofosmin) in human non-small cell lung cancer A549, multidrug-resistance associated protein (MRP) expressing cell, were investigated in vitro and in vivo. Materials and Methods: Western blot analysis and immunohistochemistry were used for detection of MRP in A549 cells with anti-MRPr1 antibody. Cellular uptakes of two tracers were evaluated at $100{\mu}M$ of verapamil (Vrp), $50{\mu}M$ of cyclosporin A (CsA) and $25{\mu}M$ of butoxysulfoximide (BSO) after incubation with MIBI and tetrofosmin for 30 and 50 min at $37^{\circ}C$, using single cell suspensions at $1{\times}10^6cells/ml$. Radioactivities in supernatants and pellets were measured with gamma well counter. A549 cells were inoculated in each flanks of 24 nude mice. Group 1 (Gr1) and Gr3 mice were treated with only MIBI or tetrofosmin, and Gr2 and Gr4 mice were treated with 70mg/kg of CsA i.p. for 1 hour before injection of 370KBq of MIBI or tetrofosmin. Mice were sacrificed at 10, 60 and 240 min. Radioactivities of organs and tumors were expressed as percentage injected dose per gram of tissue (%ID/gm). Results: Western blot analysis of the A549 cells detected expression of MRPr1 (190 kDa) and immunohistochemical staining of tumor tissue for MRPr1 revealed brownish staining in cell membrane but not P-gp. Upon incubating A549 cells for 60 min with MIBI and tetrofosmin, cellular uptake of MIBI was higher than that of tetrofosmin. Coincubation with modulators resulted in an increase in cellular uptakes of MIBI and tetrofosmin. Percentage increase of MIBI was higher than that of tetrofosmin with Vrp by 623% and 427%, CsA by 753% and 629% and BSO by 219% and 140%, respectively. There was no significant difference in tumoral uptakes of MIBI and tetrofosmin between Gr1 and Gr3. Percentage increases in MIBI (114% at 10 min, 257% at 60 min, 396% at 240 min) and tetrofosmin uptake (110% at 10 min, 205% at 60 min, 410% at 240 min) were progressively higher by the time up to 240 min with CsA. Conclusion: These results indicate that MIBI and tetrofosmin are suitable tracers for imaging MRP-mediated drug resistance in A549 tumors. MIBI may be a better tracer than tetrofosmin for evaluating MRP reversal effect of modulators.