• Korean Journal of Pharmacognosy
• /
• v.39 no.4
• /
• pp.310-315
• /
• 2008

Viscum album coloratum (Korean mistletoe; KM) is a semi-parasitic plant growing on various trees. This plant hasbeen shown to possess a variety of biological functions such as immunomodulation, apoptosis-induction and antitumor activity. However, there is no information about how the extract of KM affects life span of the host. In this study, in order to examine the effect of KM on the longevity of the host, we investigated whether a Korean mistletoe extract (KME) was able to extend the life length in an experimental model using the spring silkworm moth of Bombyx mori (Lepidoptera bombycidae). We established a model test for survival in which all of the male and female moths died within 18 days after the beginning of the experiment. Mean survival time of female moths was longer than that of male moths. Both male and female moths fed with KME containing diet (200 or 400 ${\mu}g$/head/day) showed significantly higher mean survival times than those of the control moths. Studying the effect of KME on prolongation of mean survival time showed that male moths were more susceptible than female moths. The moths fed with KME-containing diet showed a slight decrease in body weight. Interestingly, however, no difference in food intake was observed between moths fed with KME-containing diet and those with control diet. In analysis for mRNA increase in the SIRT2 gene, a member of the Sir2 gene family playing important roles in regulation of cell death and prolongation of life span, moths fed with KME-containing diet showed a significant increase in SIRT2 gene expression. These results suggest that KME has a potential to extend the life span in Bombyx mori, and its effect is partly associated with increase in SIRT2 gene expression.

• Korean Journal of Food Science and Technology
• /
• v.41 no.5
• /
• pp.597-601
• /
• 2009

Activation of hepatic stellate cells (HSCs) is known to be responsible for hepatic fibrosis and cirrhosis. When round-shape quiescent HSCs go to activation by liver injury, production of extracellular matrix is increased, and its shape becomes myofibroblast-like shape. The activated HSCs are characterized by the high rate of proliferation and the increased production of extracellular matrix. One way of the regeneration of activated HSCs is an apoptosis induction followed by removing the activated myofibroblast-like cells. The effect of extract of Terminalia chebula Retz. (TCE) on cytotoxicity was evaluated using the rat primary hepatocyte, HepG2 and T-HSC/Cl-6 by incubating these cells with TCE up to the dose of $1,000{\mu}g/mL$. At the maximum dose of TCE, no cytotoxicity was found on primary hepatocyte and HepG2, but cytotoxic effect of TCE was found on activated HSCs, and T-HSC/Cl-6 in a U-shaped dose-response manner with the highest effect at $500{\mu}g/mL$ of TCE. Finally, we confirmed the occurrence of apoptotic cell death by annexin-V/PI double staining. The population of annexin-V positive cells was increased in a dose dependent manner.

• The Korea Journal of Herbology
• /
• v.30 no.4
• /
• pp.57-64
• /
• 2015

Objectives : Oxidative stress is one of the most causes of hepatocyte injury. Gleditsia spina, the thorns ofGleditsia sinensisLam., has been known for its anti-cancer and anti-inflammatory effects in Korean medicine. The present study investigated hepatoprotective effect of Gleditsia spina water extract (GSE) against oxidative stress induced by arachidonic acid (AA) + iron in HepG2 cells.Methods : To investigate cytoprotective effect of GSE, cells were pretreated with GSE and then subsequently exposed to 10 μM AA for 12 h, followed by 5 μM iron. Cell viability was monitored by MTT assay, and expression of apoptosis-related proteins was examined by immunoblot analysis. To identify responsible molecular mechanisms, reactive oxygen species (ROS) production, GSH contents, and mitochondrial membrane potential were measured. In addition, effect of GSE on nuclear factor erythroid 2-related factor 2 (Nrf2) activation was determined by immunoblot and antioxidant response element (ARE)-driven reporter gene assays.Results : GSE pretreatment prevented AA + iron-mediated cytotoxicity in concentration dependent manner. In addition, ROS production, glutathione depletion, and mitochondrial impairment by AA + iron were significantly inhibited by GSE. Furthermore, GSE promoted translocation of Nrf2 to nucleus, which acts as essential transcription factor for induction of antioxidant genes. Increased nuclear Nrf2 that caused by GSE treatment promoted transcriptional activity of ARE. Finally, GSE up-regulated sestrin-2 which was widely recognized as target gene of Nrf2.Conclusions : This study demonstrates that GSE protects hepatocytes from oxidative stress via activation of Nrf2 signaling pathway.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.10
• /
• pp.4353-4358
• /
• 2014

Background: PI3/AKT and NF-kB signaling pathways are constitutively active in acute myeloid leukemia and cross-talk between the two has been shown in various cancers. However, their role in acute myeloid leukemia has not been completely explored. We therefore used cell penetrating inhibitor peptides to define the contributions of AKT and NF-kB to survival and multi drug resistance (MDR) in HL-60 cells. Materials and Methods: Inhibition of AKT and NF-kB activity by AKT inhibitor peptide and NBD inhibitor peptide, respectively, resulted in decreased expression of mRNA for the MDR1 gene as assessed by real time PCR. In addition, treatment of HL-60 cells with AKT and NBD inhibitor peptides led to inhibition of cell viability and induction of apoptosis in a dose dependent manner as detected by flow cytometer. Results: Finally, co-treatment of HL-60 cells with sub-optimal doses of AKT and NBD inhibitor peptides led to synergistic apoptotic responses in AML cells. Conclusions: These data support a strong biological link between NF-kB and PI3-kinase/AKT pathways in the modulation of antiapoptotic and multi drug resistant effects in AML cells. Synergistic targeting of these pathways using NF-kB and PI3-kinase/AK inhibitor peptides may have a therapeutic potential for AML and possibly other malignancies with constitutive activation of these pathways.

• Environmental Mutagens and Carcinogens
• /
• v.25 no.2
• /
• pp.51-59
• /
• 2005

Overexpression of HSP25 delayed cell growth, increased the level of $p21^{waf}$, reduced the levels of cyclin D1, cylcin A and cdc2, and induced radioresistance in L929 cells. We demonstrated that extracellular regulated kinase (ERK) and MAP kinase/ERK kinase (MEK) expressions as well as their activation (phospho-forms) were inhibited by hsp25 overexpression. To confirm the relationship between ERK1/2 and hsp25-mediated radioresistance, ERK1 or ERK2 cDNA was transiently transfected into the hsp25 overexpressed cells and their radioresistance was examined. HSP25-mediated radioresistance was abolished by overexpression of ERK2, but not by overexpression of ERK1. Alteration of cell cycle distribution and cell cycle related protein expressions (cyclin D, cyclin A and cdc2) by hsp25 overexpression were also recovered by ERK2 cDNA transfection. Increase in Bc1-2 protein by hsp25 gene transfection was also reduced by subsequent ERK2 cDNA-transfection. In addition, HSP25 overexpression reduced reactive oxygen species (ROS) and increased expression of manganese superoxide dismutase (MnSOD) gene. Increased activation of NF-kB (IkB degradation) was also found in hsp25-overexpressed cells. Moreover, transfection of hsp25 antisense gene abrogated all the HSP25-mediated phenomena. To further elucidate the exact relationship between MnSOD induction and NF-kB activation, dominant negative $I-kB\alpha(I-kB\alpha-DN)$ construction was transfected to HSP25 overexpressed cells. $I-kB\alpha-DN$ inhibited HSP25 mediated MnSOD gene expression. In addition, HSP25 mediated radioresistance was blocked by $I-kB\alpha-DN$ transfection. Blockage of MnSOD with antisense oligonucleotides in HSP25 overexpressed cells, prevented apoptosis and returned the ERK1/2 activation to the control level. From the above results, we suggest for the first time that reduced oxidative damage by HSP25 was due to MnSOD-mediated down regulation of ERK1/2.

• IMMUNE NETWORK
• /
• v.2 no.4
• /
• pp.242-247
• /
• 2002

Background: Tumor necrosis factor-alpha (TNF-$\alpha$) is known to play an important role in various conditions such as inflammation, autoimmunity, apoptosis, insulin resistance and sleep induction. Five single nucleotide polymorphisms (SNPs) have been known to affect the transcriptional activities of TNF-$\alpha$: -1,031T/C, -863C/A, -857C/T, -308G/A and -238G/A. Methods: We have investigated 5 SNPs of the promoter region of TNF-$\alpha$ gene, the distribution of 5-locus TNF-$\alpha$ haplotypes, and their haplotypic associations with previously typed HLA-A, -B and -DRB1 loci in 107 healthy unrelated Koreans. TNF-$\alpha$ SNPs were typed using PCR-single-strand conformation polymorphism (SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. Results: The allele frequencies of -1,031C, -863A, -857T, -308A, and-238A, which are known as the high-producer-type, were 19.3%, 15.9%, 14.0%, 5.9%, and 2.9%, respectively. The frequency of -308A allele, known to be associated with autoimmune diseases, was 5.9% in Koreans which was lower than Caucasians (14~17%) and somewhat higher than Japanese (1.7%). Five most common TNF-$\alpha$ haplotypes (-1,031/-863/-857/-308/-238) comprised over 95% of total haplotypes: TCCGG (58.4%), CACGG (14.8%), TCTGG (13.7%), TCCAG (5.3%), and CCCGA (3.1%). Strong positive associations (P<0.001) were observed between TCCGG and B62; between CACGG and B51, $DRB1^*0901$; between TCTGG and B35, B54, B59, $DRB1^*1201$; and between TCCAG and A33, B58, $DRB1^*0301$, $DRB1^*1302$. Five most common extended haplotypes (>3%) comprised around 16% of total haplotypes: A33-B58-TCCAG-$DRB1^*1302$, A24-B52-TCCGG-$DRB1^*1502$, A33-B44-TCCGG-$DRB1^*1302$, A24-B7-TCCGG-$DRB1^*0101$, and A11-B62-TCCGG-$DRB1^*0406$. The distribution of extended HLA and TNF-$\alpha$ haplotypes showed that most of HLA haplotypes were almost exclusively associated with particular TNF-$\alpha$ haplotypes. Conclusion: The results obtained in this study would be useful as basic data for anthropologic studies and disease association studies in Koreans.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
• /
• v.6 no.1
• /
• pp.67-79
• /
• 2000

Objective : Hedyotis diffusa has been used as an anticancer agent for several decades in oriental medicine. We test whether the methanol extract of the herb affects transcriptional activation factors including $NF-{\kappa}B$ and AP-1. Methods : 1. HL-60 cells were treated with various concentrations(from 200 to $50{\mu}g/ml$) of methanol extract and $H_2O$ extract($200{\mu}g/ml$)of hedyotis diffusa, After 48h later, the cells were tested for viability by MTT assay. 2. The HL-60 cells were treated with $200{\mu}g/ml$ of methanol extract for the indicated periods. First. Nuclear extracts were isolated and incubated with oligonucleotide probe of $NF-{\kappa}B$ and AP-1. Second. Nuclear extracts were isolated and reacted with p50, p65. c-rel pan-Jun, c-Jun, JunB. JunD antibody on ice for 30min. Finally The cell lysates were prepared and analyzed by western blotting using anti-Fas, anti-FasL and anti-p53 antibody. Results : 1. The methanol extract decreases the viability of human lymphoid origin leukemia HL-60 cells in a dose-dependent manner. 2. $NF-{\kappa}B$ is rapidly activated by the addition of the methanol extract, reaches a peak at 30min and gradually returns to resting level. We confirm that $NF-{\kappa}B$ is a heterodimer mainly composed of p65 subunit with c-Rel. 3. Transcriptional activation of AP-1 is detected at 30min and reaches a maximum at 1hr after stimulation of the cells with the methanol extract. AP-1 is mainly composed with Jur-D and partially Jug-B proteins. 4. the methanol extract of Hedyotis diffusa induces the expression of Fas, Fas ligand and p53 proteins of HL-60 cells in a time dependent fashion. Conclusions : These results suggest that the methanol extract of Hedyotis diffusa exerts anticancer effects to induce the death of human leukomic HL-60 cells via activation of trascriptional factors such as $NF-{\kappa}B$ and AP-1, increase in expression of Fas mediated signalling proteins, and induction of tumor suppressor gene. p53.

• Asian Pacific Journal of Cancer Prevention
• /
• v.16 no.14
• /
• pp.6039-6046
• /
• 2015

Aims: To investigate effect of metallic nanoparticles, silver (AgNPs) and gold nanoparticles (AuNPs) as antitumor treatment in vitro against human breast cancer cells (MCF-7) and their associated mechanisms. This could provide new class of engineered nanoparticles with desired physicochemical properties and may present newer approaches for therapeutic modalities to breast cancer in women. Materials and Methods: A human breast cancer cell line (MCF-7) was used as a model of cells. Metallic nanoparticles were characterized using UV-visible spectra and transmission electron microscopy (TEM). Cytotoxic effects of metallic nanoparticles on MCF-7 cells were followed by colorimetric SRB cell viability assays, microscopy, and cellular uptake. Nature of cell death was further investigated by DNA analysis and flow cytometry. Results: Treatment of MCF-7 with different concentrations of 5-10nm diameter of AgNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $6.28{\mu}M$, whereas treatment of MCF-7 with different concentrations of 13-15nm diameter of AuNPs inhibited cell viability in a dose-dependent manner, with IC50 value of $14.48{\mu}M$. Treatment of cells with a IC50 concentration of AgNPs generated progressive accumulation of cells in the S phase of the cell cycle and prevented entry into the M phase. The treatment of cells with IC50 concentrations of AuNPs similarly generated progressive accumulation of cells in sub-G1 and S phase, and inhibited the entrance of cells into the M phase of the cell cycle. DNA fragmentation, as demonstrated by electrophoresis, indicated induction of apoptosis. Conclusions: Our engineered silver nanoparticles effectively inhibit the proliferation of human breast carcinoma cell line MCF-7 in vitro at high concentration ($1000{\mu}M$) through apoptotic mechanisms, and may be a beneficial agent against human carcinoma but further detailed study is still needed.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.10
• /
• pp.6159-6164
• /
• 2013

Background: Phytochemical compounds are emerging as a new generation of anticancer agents with limited toxicity in cancer patients. The purpose of this study was to investigate the potential effcts of thymoquinone, caffeic acid phenylester (CAPE) and resveratrol on inflammatory markers, oxidative stress parameters, mRNA expression levels of proteins and survival of lung cancer cells in Vitro. Materials and Methods: The A549 cell line was treated with benzo(a)pyrene, benzo(a)pyrene plus caffeic acid phenylester (CAPE), benzo(a)pyrene plus resveratrol (RES), and benzo(a)pyrene plus thymoquinone (TQ). Inflammatory markers, oxidative stress parameters, mRNA expression levels of apoptotic and anti-apoptotic proteins and cell viability were assessed and results were compared among study groups. Results: TQ treatment up-regulated Bax and down-regulated Bcl2 proteins and increased the Bax/Bcl2 ratio. CAPE and TQ also up-regulated Bax expression. RES and TQ down-regulated the expression of Bcl-2. All three agents decreased the expression of cyclin D and increased the expression of p21. However, the most significant up-regulation of p21 expression was observed in TQ treated cells. CAPE, RES and TQ up-regulated TRAIL receptor 1 and 2 expression. RES and TQ down-regulated the expression of NF-kappa B and IKK1. Viability of CAPE, RES and TQ treated cells was found to be significantly decreased when compared with the control group (p=0.004). Conclusions: Our results revealed up-regulation of the key upstream signaling factors, which ultimately cause increase in their regulatory p53 levels affecting the induction of G2/M cell cycle arrest and apoptosis. Overall these results provide mechanistic insights for understanding the molecular basis and utility of the anti-tumor activity of TQ, RES and CAPE.

• Journal of Life Science
• /
• v.18 no.6
• /
• pp.884-890
• /
• 2008

Genistein, an isoflavone in soybean products, is a potential chemopreventive agent against various types of cancer. There are several studies documenting molecular alterations leading to cell cycle arrest at G2/M phase and induction of apoptosis; however, its mechanism of action and its molecular targets on the prostaglandin $E_2$ ($PGE_2$) production and telomere length regulation in human cancer remain unclear. In this study, we investigated the effect of genistein on the levels of cyclooxygenases (COXs) and telomere regulatory components of several human cancer cell lines (T24, human bladder carcinoma cells; U937, human leukemic cells; AGS, human stomach adenocarcinoma cells and SK-MEL-2, human skin melanoma cells). Genistein treatment resulted in the inhibition of cancer cell proliferation in a concentration-dependent manner. It was found that genistein treatment markedly decreased the levels of COX-2 mRNA and protein expression without significant changes in the expression of COX-1, which was correlated with a decrease in $PGE_2$ synthesis. Genistein treatment also partly inhibited the levels of human telomerase reverse transcriptase (hTERT) as well as human telomerase RNA (hTR) and telomerase-associated protein (TEP)-1, and the activity of telomerase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of genistein.