• 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.

• BMB Reports
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• v.47 no.4
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• pp.221-226
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• 2014

Drug-resistance and imbalance of apoptotic regulation limit chemotherapy clinical application for the human hepatocellular carcinoma (HCC) treatment. The reactivation of p53 is an attractive therapeutic strategy in cancer with disrupted-p53 function. Nutlin-3, a MDM2 antagonist, has antitumor activity in various cancers. The post-translational modifications of p53 are a hot topic, but there are some controversy ideas about the function of phospho-$Ser^{392}$-p53 protein in cancer cell lines in response to Nutlin-3. Therefore, we investigated the relationship between Nutlin-3 and phospho-$Ser^{392}$-p53 protein expression levels in SMMC-7721 (wild-type TP53) and HuH-7 cells (mutant TP53). We demonstrated that Nutlin-3 induced apoptosis through down-regulation phospho-$Ser^{392}$-p53 in two HCC cells. The result suggests that inhibition of p53 phosphorylation on $Ser^{392}$ presents an alternative for HCC chemotherapy.

• BMB Reports
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• v.51 no.6
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• pp.296-301
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• 2018

Mitochondrial DNA (mtDNA) mutations are often observed in various cancer types. Although the correlation between mitochondrial dysfunction and cancer malignancy has been demonstrated by several studies, further research is required to elucidate the molecular mechanisms underlying accelerated tumor development and progression due to mitochondrial mutations. We generated an mtDNA-depleted cell line, ${\rho}^0$, via long-term ethidium bromide treatment to define the molecular mechanisms of tumor malignancy induced by mitochondrial dysfunction. Mitochondrial dysfunction in ${\rho}^0$ cells reduced drug-induced cell death and decreased the expression of pro-apoptotic proteins including p53. The p53 expression was reduced by activation of nuclear $factor-{\kappa}B$ that depended on elevated levels of free calcium in $HCT116/{\rho}^0$ cells. Overall, these data provide a novel mechanism for tumor development and drug resistance due to mitochondrial dysfunction.

• BMB Reports
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• v.39 no.5
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• pp.560-570
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• 2006

Mistletoe (Viscum album) lectins, which are classified as a type II ribosome-inactivating protein (RIP) due to their unique biological function and the potential medical and therapeutic application in cancer cells, receive a rising attention. The heterodimeric glycoproteins contain the A-chain with catalytic activity and the B-chain with sugar binding properties. In recent years, studies involving the lectins from the white berry European mistletoe (Viscum album) and the yellow berry Korean mistletoe (Viscum album coloratum) have been described. However, the detailed mechanism in exerting unique cytotoxic effect on cancer cells still remains unclear. Here, we aim to understand and define the molecular basis and biological effects of the type II RIPs, through the studies of the recombinant Korean mistletoe lectin. To this end, we expressed, purified the recombinant Korean mistletoe lectin (rKML), and investigated its molecular characteristics in vitro, its cytotoxicity and ability to induce apoptotic cell death in cancer cells. To gain structural basis for its catalytic activity and sugar binding properties, we performed homology modeling studies based on the high degree of sequence identity and conserved secondary structure prediction between Korean and European, Himalayan mistletoe lectins, and Ricin.

• The Journal of Internal Korean Medicine
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• v.37 no.6
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• pp.1030-1041
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• 2016

Objectives: This study investigated the administration of Jeungmiyijin-tang (JYT) to rats with reflux esophagitis (RE) induced by pylorus and forestomach ligation operations. Methods: Twenty laboratory rats were divided into three groups with 5~7 rats in each group. The control group consisted of rats with no inflammation (CON). The RE group had rats with gastroesophageal reflux elicited by pylorus and forestomach ligation operations. The JYT group had rats that were orally administered Jeungmiyijin-tang (1.5 ml/day/300 g) once a day for 14 days before reflux esophagitis was induced by the pylorus and forestomach ligation operations. Six hours after the operations, the rats were sacrificed, morphological changes were observed, and histological examinations were done in the stomach and esophagus lesion areas. If apoptosis was observed, the apoptotic cells in the esophagus lesion areas were counted. Results: The morphological and histochemical changes consisted of various injuries from hemorrhagic erosion in the RE group, while there were significantly fewer in the JYT group. The RE group marked increases of gastric mucosa erosion and infiltration of inflammatory cells in the submucosa, as well as cell division in the epithelial layer, the proliferation and degranulation of mast cells, and increases in the IL-$1{\beta}$, TNF-${\alpha}$, and MMP-9 expressions in the esophagus of the rats. The JYT group was inhibited above expression compared with the RE group. Apoptosis was statistically significantly decreased in the JYT group compared with the RE group. Conclusions: According to the above results, it appears that Jeungmiyijin-tang inhibits the expression of pro-inflammatory cytokines (TNF-${\alpha}$, IL-$1{\beta}$, and MMP-9) and apoptosis in the esophagus mucosa, thereby preventing esophageal mucosal damage from esophageal reflux.

• Biomolecules & Therapeutics
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• v.25 no.4
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• pp.396-403
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• 2017

Under normal, non-stressed conditions, intracellular p53 is continually ubiquitinated by MDM2 and targeted for degradation. However, in response to severe genotoxic stress, p53 protein levels are markedly increased and apoptotic cell death is triggered. Inhibiting the ubiquitination of p53 under conditions where DNA damage has occurred is therefore crucial for preventing the development of cancer, because if cells with severely damaged genomes are not removed from the population, uncontrolled growth can result. However, questions remain about the cellular mechanisms underlying the regulation of p53 stability. In this study, we show that p53-inducible gene 3 (PIG3), which is a transcriptional target of p53, regulates p53 stability. Overexpression of PIG3 stabilized both endogenous and transfected wild-type p53, whereas a knockdown of PIG3 lead to a reduction in both endogenous and UV-induced p53 levels in p53-proficient human cancer cells. Using both in vivo and in vitro ubiquitination assays, we found that PIG3 suppressed both ubiquitination- and MDM2-dependent proteasomal degradation of p53. Notably, we demonstrate that PIG3 interacts directly with MDM2 and promoted MDM2 ubiquitination. Moreover, elimination of endogenous PIG3 in p53-proficient HCT116 cells decreased p53 phosphorylation in response to UV irradiation. These results suggest an important role for PIG3 in regulating intracellular p53 levels through the inhibition of p53 ubiquitination.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7641-7651
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• 2015

It has been shown previously that nutritional supplements rich in polyphenolic compounds play a significant role in prostate cancer chemoprevention. Propolis is a natural, resinous hive product that has several pharmacological activities including antimicrobial, antioxidant, anti-inflammatory, and antitumoral activities. The aim of this study was to compare the cytotoxic, antioxidant and antitumoral activities of an ethanolic extract of Egyptian propolis (EEP) in vitro with an established chemotherapeutic drug such as doxorubicin (DOX), and the effects of their combination against the PC3 human prostate cancer cell line. Cellular viability and $IC_{50}$ levels with EEP, DOX and their (v/v) combination were detected by sulphorhodamine-B (SRB) assay after incubation of PC3 cells for 72h with different doses (0, 0.01, 0.1, 1, 10 and $100{\mu}g/ml$). Two selected doses of $IC_{50}$ and $IC_{25}$ were applied to cells for 24h for antitumor evaluation assay of treatment compounds. EEP and its (v/v) combination with DOX showed significant antitumor potential besides high antioxidant properties of superoxide dismutase (SOD), total antioxidant capacity (TAC), catalase (CAT), nitric oxide (NO) and reduced glutathione (GSH) levels when compared with the control untreated cells. DNA fragmentation assay and semi quantitative RT-PCR analyses for p53 and Bax genes showed that EEP activated cellular apoptosis and increased the mRNA expression levels more than other treatment. In conclusion, EEP alone or in combination with DOX at both doses used here showed greater antioxidant, antiproliferative and apoptotic effects against the PC3 cell lines as compared to treatment with DOX alone. Therefore, EEP could be considered as a promising candidate for prostate cancer chemotherapy.

• Applied Microscopy
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• v.38 no.3
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• pp.245-250
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• 2008

Etoposide (Eto) is chemotherapeutic compounds that is currently used in the treatment of metastatic prostate cancer but new therapeutic agents are needed for the treatment of androgen-independent prostate cancer. The objective of the present study was to determine whether vitamin C (VC), the antioxidant, plays a role in regulating the growth of prostate cancer cell lines and whether VC has synergistic effect to tumor cell killing by chemotherapeutic drugs. Androgen-dependent LNCaP and androgen-independent DU-145 prostate cancer cell lines were used in this study. Both cells presented increase of dose- and time-dependent cytotoxicity in Eto-treated cultures. The combined treatment with Eto and VC significantly increased the percentage of apoptotic cells compared to Eto-treated cells(p<0.05). The present findings demonstrated that VC inhibited the growth of prostate cancer cell lines by Eto-mediated cytotoxicity and induced apoptosis. These results suggest that the chemotherapeutic effect of Eto on prostate cancer can be enhanced by VC.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.195-200
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• 2011

Neuronal cell death is a common characteristic feature of a variety of neurodegenerative disorders including Alzheimer's disease and Parkinson's disease. However, there have been no effective drugs to successfully prevent neuronal death in those diseases. In the present study, docosyl cafferate (DC), a derivative of caffeic acid, was isolated from Rhus verniciflua and its protective effects on tBHP-induced neuronal cell death were examined in SH-SY5Y human neuroblastoma cells. Pretreatment of DC significantly attenuated tBHP-induced neuronal cell death in a concentration-dependent manner. DC also significantly suppressed tBHP-induced caspase-3 activation. In addition, DC restored tBHP-induced depletion of intracellular Bcl-2, an anti-apoptotic member of the Bcl-2 family. Furthermore, DC significantly suppressed tBHP-induced degradation of IKB, which retains $NF-{\kappa}B$ in the cytoplasm, resulting in the suppression of nuclear translocation of $NF-{\kappa}B$ and its subsequent activation. Taken together, the results clearly demonstrate that DC exerts its neuroprotective activity against tBHP-induced oxidative stress through the suppression of nuclear translocation of $NF-{\kappa}B$.

• Journal of Chest Surgery
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• v.39 no.9 s.266
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• pp.668-673
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• 2006

Background: Docetaxel has been effectively used as an anti-cancer chemotherapuetic agent for various tumor treatments including lung cancer. However, the cell death induction mechanism(s) involved with docetaxel treatment in lung cancer cells has not been known yet. Material and Method: In the present study, the cellular and biochemical changes of NCI-H1703 cells (non-small cell lung cancer cell line, p53-mutant) after docetaxel treatment have been monitored by flow cytometry, fluorescence microscopy and western blot. Result: Docetaxel treatment significantly resulted in decrease of S phase as well as increase of G2 phase, and consequently evoked an increase of cell death in NCI-H1703 cells. After docetaxel exposure the activations of caspase-3 and caspase-9 were detected. Conclusion: Take together, it is suggested that the docetaxel induces NCI-H1703 cell death by caspase-9 and caspase-3 dependent mitochondrial apoptotic pathway.