• The Korean Journal of Physiology and Pharmacology
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• v.14 no.6
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• pp.391-397
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• 2010

E2F transcription factors and their target genes have been known to play an important role in cell growth control. We found that curcumin, a polyphenolic phytochemical isolated from the plant Curcuma longa, markedly suppressed E2F4 expression in HCT116 colon cancer cells. Hydrogen peroxide was also found to decrease E2F4 protein level, indicating the involvement of reactive oxygen species (ROS) in curucmin-induced downregulation of E2F4 expression. Involvement of ROS in E2F4 downregulation in response to curcumin was confirmed by the result that pretreatment of cells with N-acetylcystein (NAC) before exposure of curcumin almost completely blocked the reduction of E2F4 expression at the protein as well as mRNA level. Anti-proliferative effect of curcumin was also suppressed by NAC which is consistent to previous reports showing curcumin-superoxide production and induction of poly (ADP-ribose) polymerase (PARP) cleavage as well as apoptosis. Expression of several genes, cyclin A, p21, and p27, which has been shown to be regulated in E2F4-dependent manner and involved in the cell cycle progression was also affected by curcumin. Moreover, decreased (cyclin A) and increased (p21 and p27) expression of these E2F4 downstream genes by curcumin was restored by pretreatment of cells with NAC and E2F4 overexpression which is induced by doxycycline. In addition, E2F4 overexpression was observed to partially ameliorate curcumin-induced growth inhibition by cell viability assay. Taken together, we found curcumin-induced ROS down-regulation of E2F4 expression and modulation of E2F4 target genes which finally lead to the apoptotic cell death in HCT116 colon cancer cells, suggesting that E2F4 appears to be a novel determinant of curcumin-induced cytotoxicity.

• The Korean Journal of Physiology and Pharmacology
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• v.22 no.6
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• pp.617-625
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• 2018

Neddylation is a post-translational protein modification process. MLN4924 is a newly discovered pharmaceutical neddylation inhibitor that suppresses cancer growth with several cancer types. In our study, we first investigated the effect of MLN4924 on colon cancer cells (HCT116 and HT29). MLN4924 significantly inhibited the neddylation of cullin-1 and colon cancer cell growth in a time and dose-dependent manner. MLN4924 induced G2/M cell cycle arrest and apoptosis in HCT116 and HT29 cells. Moreover, MLN4924 also triggered autophagy in HCT116 and HT29 cells via suppressing the PI3K/AKT/mTOR pathway. Inhibiting autophagy by autophagy inhibitor 3-MA or ATG5 knockdown reversed the function of MLN4924 in suppressing colon cancer cell growth and cell death. Interestingly, MLN4924 suppresses colon cell growth in a xenograft model. Together, our finding revealed that blocking neddylation is an attractive colon cancer therapy strategy, and autophagy might act as a novel anti-cancer mechanism for the treatment of colon cancer by MLN4924.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2943-2948
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• 2012

Arsenic exposure is a serious health hazard worldwide. We have previously established that it may result in immune suppression by upregulating Th2 cytokines while downregulating Th1 cytokines and causing lymphocytic death. Treatment modalities for arsenic poisoning have mainly been restricted to the use of chelating agents in the past. Only recently have combination therapies using a chelating agent in conjunction with other compounds such as anti-oxidants, micronutrients and various plant products, been introduced. In the present study, we used T11TS, a novel immune potentiating glycopeptide alone and in combination with the sulfhydryl-containing chelator, mono-iso-amyl-dimarcaptosuccinic acid (MiADMSA) as a therapeutic regimen to combat arsenic toxicity in a mouse model. Results indicated that Th1 cytokines such as TNF-${\alpha}$, $IFN{\gamma}$, IL12 and the Th2 cytokines such as IL4, IL6, IL10 which were respectively downregulated and upregulated following arsenic induction were more efficiently restored to their near normal levels by T11TS alone in comparison with the combined regimen. Similar results were obtained with the apoptotic proteins studied, FasL, BAX, BCL2 and the caspases 3, 8 and 9, where again T11TS proved more potent than in combination with MiADMSA in preventing lymphocyte death. The results thus indicate that T11TS alone is more efficient in immune re-establishment after arsenic exposureas compared to combination therapy with T11TS+MiADMSA.

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.241-246
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• 2014

Acute promyelocytic leukemia (APL) is a cancer of the blood. Although electron beam (EB) irradiation is used with other anti-cancer agents, EB irradiation can be harmful to normal tissues around the cancer. In the present study, we evaluate the differential cytotoxic effect of EB irradiation with other molecules, including TNF-${\alpha}$, on DMSO-treated HL-60 cells and HL-60 cells. HL-60 cells are the human promyleocytic leukemia cell line and are differentiated by DMSO. DMSO-treated HL-60 cells are considered to be normal granulocytic cells. In these results, TNF-${\alpha}$ may be used as the potential agent for the treatment of blood cancer without side effects in low dose of EB irradiation therapy.

• Korean Journal of Plant Resources
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• v.33 no.5
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• pp.460-466
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• 2020

In this study, we evaluated the anti-cancer activity and potential molecular mechanism of 70% ethanol extracts of leaves from Rodgersia podophylla against human colorectal cancer cells, HCT116. RPL dose-dependently decreased the cell viability through RPL-induced apoptosis in HCT116 cells. RPL induced inactivation the nuclear factor κB(NF-κB) through blocking IκB-α degradtion and P65 nuclear accumulation. The inhibition of GSK3β by LiCl attenuated RP-L-mediated NF-κB signaling inactivation. In addition, RP-L induced GSK3β activation. Based on these findings, RPL may be a potential candidate for the development of chemopreventive or therapeutic agents for human colorectal cancer.

• Korean Journal of Oriental Medicine
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• v.8 no.2 s.9
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• pp.95-107
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• 2002

Yukmijihwang-tang(YM) is a noted herbal prescription in Chinese and Korean traditional medicines, and it has been known to reinforce the vital essence and has been widely used for a variety of disease such as stroke, osteoporosis, anti-tumor, and hypothyrodism. Regarding its traditional use, YM has been known to reinforce the Yin (vital essence) of liver and kidney. Also it has been known to reinforce nutrition and biological function in brain. Recently, studies suggested that YM increase antioxidant activities and exert the protective effect against oxidant-induced liver cell injury. We investigated the high-throughput gene expression analysis on the Yukmijihwang-tang administrated in SD rats. Microarray data were validated on a limited number of genes by semiquantitative RT-PCR and Western blot analyses. The recent availability of microarrays provides an attractive strategy for elaborating an unbiased molecular profile of large number of genes in drug discovery This experimental approach offers the potential to identify molecules or cellular pathways not previously associated with herbal medicine. Total RNA from normal control brain and Yukmijihwang-tang administrated brain were hybridized to microarrays containing 10,000 rat genes. The 52 genes were found to be up-regulated(twice or more) excluding EST gene. The nine genes were found to be down-regulated(twice or more) excluding EST gene. Gene array technology was used to identify for the first time many genes expression pathway analysis that arecell cycle pathway, apoptosis pathway, electron transport chain pathway, cytoplasmic ribosomal protein pathway, fatty acid degradation pathway, and TGF-beta signaling pathway. These differentially expressed genes pathway analysis have not previously been iavestigated in the context of herbal medicine efficacy and represent novel factors for further study of the mechanism of herbal medicine efficacy.

• Korean Journal of Oriental Medicine
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• v.18 no.1
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• pp.75-84
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• 2012

Objective : The purpose of this study was to investigate the anti-cancer effects of Sophorae Radix and the effects of Doxorubicin (DOX) in human breast adenocarcinoma cells (MCF-7). Method : We used human breast adenocarcinoma cell line, MCF-7 cells. We examined cell death by MTT assay and caspase 3 assay with Sophorae Radix. To examine the inhibitory effects of Sophorae Radix, cell cycle analysis was done the MCF-7 cells after three days with Sophorae Radix. The reversibility of Sophorae Radix was examined on one day to five days treatment with 100 ${\mu}g/ml$ Sophorae Radix. Result : Sophorae Radix inhibited the growth of MCF-7 cells in a dose-dependent fashion. Also we showed that Sophorae Radix induced apoptosis in MCF-7 cells by MTT assay, caspase 3 assay and sub-G1 analysis. Sophorae Radix combined with DOX markedly inhibited the growth of MCF-7 cells compared to Sophorae Radix or DOX alone. After 3 days treatment of MCF-7 cells with Sophorae Radix, the fraction of cells in sub-G1 phase was much higher than that of the control group. Conclusion : Our findings provide insight into unraveling the effects of Sophorae Radix in human breast adenocarcinoma cells and developing therapeutic agents against breast cancer.

• BMB Reports
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• v.47 no.5
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• pp.274-279
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• 2014

Bortezomib has been known as the most promising anti-cancer drug for multiple myeloma (MM). However, recent studies reported that not all MM patients respond to bortezomib. To overcome such a stumbling-block, studies are needed to clarify the mechanisms of bortezomib resistance. In this study, we established a bortezomib-resistant cell line (U266/velR), and explored its biological characteristics. The U266/velR showed reduced sensitivity to bortezomib, and also showed cross-resistance to the chemically unrelated drug thalidomide. U266/velR cells had a higher proportion of CD138 negative subpopulation, known as stem-like feature, compared to parental U266 cells. U266/velR showed relatively less inhibitory effect of prosurvival NF-${\kappa}B$ signaling by bortezomib. Further analysis of RNA microarray identified genes related to ubiquitination that were differentially regulated in U266/velR. Moreover, the expression level of CD52 in U266 cells was associated with bortezomib response. Our findings provide the basis for developing therapeutic strategies in bortezomib-resistant relapsed and refractory MM patients.

• BMB Reports
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• v.51 no.10
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• pp.538-543
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• 2018

Pancreatic beta cell destruction and dysfunction induced by cytokines is a major cause of type 1 diabetes. Paraoxonase 1 (PON1), an arylesterase with antioxidant activity, has been shown to play an important role in preventing the development of diabetes in transgenic mice. However, no studies have examined the anti-diabetic effect of PON1 delivered to beta cells using protein transduction. In this study, we expressed the cell-permeable PON1 fused with PEP-1 protein transduction domain (PEP-1-PON1) to investigate whether transduced PEP-1-PON1 protects beta cells against cytokine-induced cytotoxicity. PEP-1-PON1 was effectively delivered to INS-1 cells and prevented cytokine-induced cell destruction in a dose-dependent manner. Transduced PEP-1-PON1 significantly reduced the levels of reactive oxygen species (ROS) and nitric oxide (NO), DNA fragmentation, and expression of inflammatory mediators, endoplasmic reticulum (ER) stress proteins, and apoptosis-related proteins in cytokine-treated cells. Moreover, transduced PEP-1-PON1 restored the decrease in basal and glucose-stimulated insulin secretion induced by cytokines. These data indicate that PEP-1-PON1 protects beta cells from cytokine-induced cytotoxicity by alleviating oxidative/nitrosative stress, ER stress, and inflammation. Thus, PEP-1-mediated PON1 transduction might be an effective method to reduce the extent of destruction and dysfunction of pancreatic beta cells in autoimmune diabetes.

• BMB Reports
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• v.53 no.8
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• pp.419-424
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• 2020

Bee venom (BV), secreted from the venom gland of the honey bee, contains several biological active compounds. BV has been widely used as a traditional medicine for treating human disease, including cancer. In this study, we have shown the molecular mechanism underlying the therapeutic effect of BV on cancer. Treatment with BV reduced the proliferation of cervical-cancer cells in a dose- and time-dependent manner. Interestingly, the killing effect of BV was specific to HPV-positive cervical-cancer cell lines, such as Caski and HeLa cells, and not to HPV-negative cervical-cancer cells (C33A). BV reduced the expression of HPV E6 and E7 at RNA and protein levels, leading to an increase in the expression of p53 and Rb in Caski and HeLa cells. Further, BV decreased the levels of cell-cycle proteins, such as cyclin A and B, and increased the levels of cell-cycle inhibitors, such as p21 and p27. BV significantly induced apoptosis and inhibited wound healing and migration of cervical-cancer cells. It also upregulated the expression of pro-apoptotic BAX and downregulated the expression of anti-apoptotic Bcl-2 and Bcl-XL. Cleavage of caspase-3, caspase-9, and PARP were also induced by BV treatment, whereas the phosphorylation of mitogenic signaling-related proteins, such as AKT, JNK, p38, and ERK, were downregulated. Our results indicate that BV has a therapeutic selectivity for HPV-positive malignant cells, so further clinical studies are needed to assess its clinical application.