• Biomedical Science Letters
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• v.13 no.2
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• pp.75-81
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• 2007

Sodium salicylate (NaSal), a chemopreventive drug, has been shown to induce apoptosis and cell circle arrest depending on its concentrations in a variety of cancer cells. In A549 cells, low concentration of NaSal (5$\sim$10 mM) induces cell cycle arrest, whereas it induces apoptosis at higher concentration of 20 mM. In the present study, we examined the molecular mechanism for NaSal-induced cell cycle arrest. NaSal induced expression of p53, p21 (Wafl/Cipl), and p27 (Kipl) that play important roles in cell cycle arrest. p53 induction was mediated by its phosphorylation at Ser-15 that could be prevented by the PI3K-related kinase (ATM, ATR and DNA-PK) inhibitors including wortmannin, caffeine and LY294002. In addition, NaSal-induction of p2l (Wafl/Cipl) was detected in P53 (+/+) wild type A549 cells but not in p53 (-/-) mutant H1299 cells, indicating p53-dependent p21 (Wafl/Cipl) induction. In contrast, p27 (Kipl) that is a negative regulate. of cell cycle with p21 (Wafl/Cipl) was observed both in A549 cells and H1299 cells. Thus, 5 mM NaSal appeared to cause cell cycle arrest through inducing the cyclin-dependent kinase inhibitor p21 (Wafl/Cipl) via PI3K-related protein kinase-dependent p53 activation as well as by up-regulating p27 (Kipl) independently of p53 in A549 cells.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.144.1-144.1
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• 2003

We previously reported that the activation of p$21^{WAFl/Cip1}$ transcription by histone deacetylase inhibitor apicidin was mediated through Spl sites and pointed to the possible participation of protein kinase C (PKC). In this study, we investigated the role and identity of the specific isoforms of PKC involved and identified phosphatidylinositol 3-kinase (PI 3-kinase) as an upstream effector in HeLa cells. Using an isoform-specific pharmacological inhibitor of PKC, a PKC$\varepsilon$ dominant-negative mutant, and antisense oligonucleotide to inhibit PKC$\varepsilon$ specifically, (omitted)

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.152.2-153
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• 2003

${\beta}Although$ it has been demonstrated that $p2l^{WAFl/Cip1}$, a well known cell cycle inhibitor, could be induced by $TGF-{\beta}$ in a p53-independent manner, the detailed signal transduction pathways still remain poorly understood. In this study, we show that ERK is required for $TGF-{\beta}$ induction of $p21^{WAF1/Cip1}$, but JNK or p38 MAPK is not. ERK activation by $TGF-{\beta}$ significantly attenuated by treatment with ROS scavenger such as NAC or catalase, indicating that ROS, mainly $H_2O_2$, generation by $TGF-{\beta}$ might stimulate ERK signaling pathway to require the induction of $p21^{WAF1/Cip1}$. (omitted)

• Proceedings of the Korean Magnetic Resonance Society Conference
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• 1999.02a
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• pp.22-22
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• 1999

• The Journal of Korean Medicine
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• v.19 no.1
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• pp.145-164
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• 1998

The purpose of this study is to evaluate the effect of Injinchunggantang-derivative on proliferation of hepatocyte in rats. Cell viability is studied by MTI assay. The gene related to cell replication such as p53, waf1, bcl-2 and $bcl-_{X_L}$ is quantitized by quantitative RT-PCR and the proteins coded by these genes are studied by Western blotting. The results are as follows. 1. The hepatocytes cultured in medium with lnjinchunggantang-derivative showed better viability compared with control grroup in MTI assay, and the hepatocytes cultured in medium with the Injinchunggantang-derivative-and-ethanol-mixed group showed better viability than the hepatocytes cultrued in 10% ethanol culture medium(control group), noting that Injinchunggantang-derivative has protective effect on hepatocyte injury. There was no dose- and time-dependence. 2. In quantitative RT-PCR, i) Bel-2 gene increased significantly both in Injinchunggantang-derivative group and in Injinchunggantang-derivative-and-ethanol-mixed group, while it showed no significant increase or decrease in other group. ii) $Bcl-_{X_L}$ gene increased significantly in Injinchunggantang-derivative group as well as in Injinchunggantang-deri vative-and-ethanol -mixed group. iii) P53 gene showed no significant increase or decrease in hepatocytes cultured in medium with 10% ethanol and in hepatocytes cultured in medium with Injinchunggantang-derivative-and-ethanol-mixed group, suggesting that 10% ethanol induced cell toxicity, thus increased p53 gene expression. iv) Wafl gene showed no significant increase or decrease in hepatocytes cutured in medium with Injinchtrnggantang-derivative, while increased in hepatocytes cultured in medium with 10% ethanol and in hepatocytes cultured in medium with Injinchtrnggantang-derivative-andethanol-mixed group, suggesting that 10% ethanol induced cell toxicity increased wafl gene expression. 3. In the study on protein by western blotting, the band of bcl-2 and $bcl-_{X_L}$ were widened in Injinchtrnggantang-derivative group. Especially the amount of $bcl-_{X_L}$ increased significantly compared with other groups. But in the study on p53 and wafl, there was no significant difference among those groups. Above study shows that Injinchunggantang-derivative has good effect on cell viability and that the genes resistant to cell death such as bcl-2 and $bcl-_{X_L}$ are induced by Injinchunggantang-derivative to resist to cell death by toxic agent And this is reconfirmed in protein study using' western blotting: These results suggest that Injinchunggantang-derivative has inhibitory effect on cell death as well as protective effect on hepatocyte. Therefore this prescription is recommended in various liver diseases such as chronic liver disease and-induced hepatic injury.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.7 no.1
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• pp.1-18
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• 2001

Objective: This experimental study was carried out to evaluate the effects of Saussurea Radix and Plantaginis Herba on cellular viability, proliferation, apoptosis and expression of the cell cycle-related genes in cultured gastric cancer cells. Method :MTT assay for analysis of cellular toxicity and the effect on suppression of cellular viability, $[^{3}H]$ thymidine incorporation assay for evaluation of the effect on suppression of DNA replication, tryphan blue exclusion assay for measurement of induction of apoptosis and Quantitative RT-PCR for analysis of the effects on expression of cell cycle or apoptosis-related genes were performed. Results: Antitumor activity of Saussurea Radix associated with inhibition of cell cycle progression and promotion of apoptosis caused by transcriptional regulation of p53, p21/Wafl and the other related genes was observed.

• The Journal of Internal Korean Medicine
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• v.24 no.1
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• pp.134-143
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• 2003

Objectives : We performed this study to understand the molecular basis of the antitumor effect of Saussurea lappa, Pharbitis nil, Plantago asiatica and Taraxacum mongolicum, which have been used for cancer treatment in Korean traditional medicine. Design: We analyzed, the effect of these medicinal herbs on proliferation and apoptosis of tumor cells and its association with gene expression, We performed semi-quantitative reverse transcription-polymerase chain reaction(RT-PCR) analysis of cell cycle- and apoptosis-related genes using a gastric cancer cell line AGS. Results : Cell counting assay and $[^3H]thymidine$ uptake analysis showed that Saussurea lappa and Pharbitis nil strongly inhibit cell proliferation of AGS in a dose-dependent manner. Interestingly, gene espression assay revealed that mRNA espression levels of c-Jun, c-Fos, c-Myc, and Cyclin D1 were markedly decreased by Saussurea lappa and Pharbitis nil. Furthermore, Saussurea lappa was identified to activate expression of the p53 tumor suppressor and its downstream effector $p21^{Wafl}$, which leads to $G_1$ cell cycle arrest and apoptosis. These observations suggest that the anticancer effect of Saussurea lappa and Pharbitis nil might be associated with their regulatory capability of tumor-related gene expression.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.6
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• pp.1843-1849
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• 2004

Conventional medicines have usually sorted to a number of treatments such asoperation, radiotherapy, and chemotherapy. The existing anti-cancer agents, designed to eradicate cancer cells, have strong toxicities, also with leading to harmful side effects. Recently, a number of researches on natural products have been actively carried out in efforts to develop new treatments that can decrease side effects or increase anti-cancer effects. We performed this study to understand the molecular basis underlying the antitumor effects of Pharbitis nil, and Plantago asiatica, which have been used for herbal medicinal treatments against cancers in East Asia. We analyzed the effects of these medicinal herbs on proliferation and on expression of cell growth/apoptosis related molecules, with using an AGS gastric cancer cell line. The treatment of Pharbitis nil dramatically reduced cell viabilities in a dose and time-dependent manner, but Plantago asiatica didn't. FACS analysis and Annexin V staining assay also showed that Pharbitis nil induce apoptotic cell death of AGS. Expression analyses via RT-PCR and Western blots revealed that Pharbitis nil didn't increase expression of the p53 and its downstream effector p21/sup wafl/, and that the both increased expression of apoptosis related Sax and cleavage of active caspase-3 protein. We also confirmed the translocation of Sax to mitochondria. Collectively, our data demonstrate that Pharbitis nilinduce growth inhibition and apoptosis of human gastric cancer cells, and these effects are correlated with down- and up-regulation of growth-regulating apoptotic and tumor suppressor genes, respectively.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.4
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• pp.1186-1191
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• 2004

The root of Saussurea lappa includes sesquiterpene lactones such as costunolide and dehydrocostus lactone, and has been shown to be anti-tumorigenic with being used in traditional medicinal therapy in the Eastern Asia. However, the molecular basis of the effects of Saussurea lappa on fate of gastric carcinoma, which incur very frequently in the area, has not been well identified. In this study, the cytostatic effects of Saussurea lappa were examined using gastric AGS cancer cells. Cell viability was dramatically reduced by Saussurea lappa, in a dose-dependent manner. As time passed after its treatment, apoptotic population was increased and clearly showed G2-arrest. Being consistent, its treatment resulted in maintaining of G1 and S-phase cyclins D1, E, and A even until a significant apoptotic population was observed, for example, at 24h after treatment. However, G2/M phase cyclin B1 was reduced even at 12 h after treatment. In addition, its treatment increased expression of p53, p21/sup Wafl / cyclin dependent kinase inhibitor (CKI), and Bax, resulted in cleavages of procaspase 3 and poly ADP-ribose polymerase(PARP), indicating that such G2 arrest- and apoptosis-related molecules are involved. Therefore, these suggest that extracts of Saussurea lappa root may be a safer and effective reagent to deal with gastric cancers either by traditional herbal therapy or combinational therapy with conventional chemotherapy.

• Journal of Acupuncture Research
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• v.18 no.1
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• pp.129-145
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• 2001

Objectives : To characterize the antitumorigenic potential of three representative bee venom components, Melittin, Apamin, and Phospholipase A2, their effects on cell proliferation and apotosis of the human melanoma cell line SK-MEL-2 were analyzed using molecular biological approaches. Methodes & Results : To determine the doses of the drugs that do not induce cytotoxic damage to this cell line, cell viability was examined by MTT assay. While SK-MEL-2 cells treated with 0.5 - 2.0㎍/㎖ of each drug showed no recognizable cytotoxic effect, marked reductions of cell viability were detected at concentrations over 5.0㎍/㎖. [3H]thymidine incorporation assay for cell proliferation demonstrated that DNA replication of SK-MEL-2 cells is inhibited by Apamin and Phospholipase A2 in a dose-dependent manner. Consistent with this result, the cells were accumulated at the G1 phase of the cell cycle after treatment with Apamin and Phospholipase A2, whereas no detectable change in cell proliferation was identified by Melittin treatment. In addition, tryphan blue exclusion and flow cytometric analyses showed that all of these drugs can trigger apoptotic cell death of SK-MEL-2, suggesting that Melittin, Apamin, and Phospholipase A2 have antitumorigenic potential through the suppression of cell growth and/or induction of apoptosis. Qantitative RT-PCR analysis revealed that Apamin and Phospholipase A2 inhibit expression of growth-promoting genes such as c-Jun, c-Fos, and Cyciin D1. Furthermore, Phospholipase A2 induced tumor suppressors p53 and p21/Wafl. In addition, all three drugs were found to activate expression of a representative apoptosis-inducing gene Bax while expression of apoptosis-suppressing Bcl-2 and Bcl-XL genes was not changed. Taken together, this study strongly suggests that Metittin, Apamin, and Phosphalipase A2 may have antitumorigenic activities, which are associated with its growth-inhibiting and/or apoptosis-inducing potentials.