• 동의생리병리학회지
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• 제17권1호
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• pp.165-176
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• 2003

The present study was carried out to examine the effects of Kami-hwal-hyeol-tang(KHHT) on the immune responses of synoviocyte cells prepared from the rheumatoid arthritis patients, and also on the collagen-mediated arthritis in mouse model. Several experiments were performed in vitro and in vivo to analyse the immunomodulatory effects of KHHT, and the major findings are summarized below: 1. KHHT did not show the cytotoxicity against mLFCs and hFLSs. 2. KHHT inhibited gene expression of IL-1β, IL-6, TNF-α, COX-2, NOS and GM-CSF in hFLSs. Furthermore, KHHT-treated hFLSs showed reduced production of pro-inflammatory cytokines such as IL-1β and IL-6 compared to the control cells. 3. KHHT treatment of hFLSs inhibited the binding activity of NF-kB and AP-1 to their consensus DNA sequences. 4. KHHT treatment(400 ㎍/㎖) of hFLSs significantly inhibited hFLSs proliferations compared to the control cells. 5. KHHT significantly reduced the production of ROS in hFLSs compared to the control cells. The present data show that KHHT plays an important role for the regulation of AP-1 and NF-kB gene expression. Also, it was found that KHHT has anti-arthritis effect. Further studies of KHHT in relation to RA therapeutics may provide important information to develop drugs to treat this disease.

• Mycobiology
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• 제40권1호
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• pp.47-52
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• 2012

$Elfvingia$ $applanata$, a medicinal mushroom belonging to Basidiomycota, has been used in the effort to cure cancers of the esophagus and stomach, and is also known to have inhibitory effects on hepatitis B virus infection. The hot water soluble fraction (as Fr. HW) was extracted from fruiting bodies of the mushroom. $In$ $vitro$ cytotoxicity tests showed that hot water extract was not cytotoxic against cancer cell lines such as Sarcoma 180, HT-29, HepG2, and TR at concentrations of 10-2,000 ${\mu}g/mL$. Intraperitoneal injection with Fr. HW resulted in a life prolongation effect of 45.2% in mice previously inoculated with Sarcoma 180. Treatment of Fr. HW resulted in a 2.53-fold increase in the numbers of murine spleen cells at a concentration of 50 ${\mu}g/mL$, compared with control. Incubation of murine spleen cells with Fr. HW at a concentration of 500 ${\mu}g/mL$ resulted in improved immune-potwntiating activity of B lymphocytes through an 8.3-folds increase in alkaline phosphatase activity, compared with control. Fr. HW generated 12.5 ${\mu}M$ of nitric oxide (NO) when cultured with RAW 264.7, a mouse macrophage cell line, at the concentration of 50 ${\mu}g/mL$, while lipopolysaccharide, a positive control, produced 15.2 ${\mu}M$ of NO. Therefore, the results suggested that antitumor activities of Fr. HW from $E.$ $applanata$ might, in part, be due to host mediated immunostimulating activity.

• Biomolecules & Therapeutics
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• 제1권2호
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• pp.131-136
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• 1993

In the present study, the effect of $HgCl_2$on the function of human peripheral polymorphonuclear leukocytes(PMNs) was examined. PMNs were isolated from human peripheral blood with density centrifugation in Ficoll-Paque. The cells were then incubated with $0.5{\sim}5{\mu}M\;HgCl_2$and glass adherence, chemotactic activity and erythrocyte-antibody rosette forming activity were measured. $HgCl_2$ decreased the function of PMNs in all three aspects tested. $HgCl_2$significantly diminished glass adherence(40.5 {\mu}M: 92{\pm}12%$ (percentage of control, $mean{\pm}$ S.D.); 41 {\mu}M: 46{\pm}11%,$ P<0.01; $3{\mu}M: 35{\pm}7%,$P<0.01;$5{\mu}M:49{\pm}10%,$ P<0.01). Similarly, significant differences were observed in chemotactic activity after $HgCl_2$treatment compared with control (control: $0.95{\pm}0.14mm; 0.5 {\mu}M: 0.91{\pm}0.11 mm; 1 {\mu}M: 0.77{\pm}0.16mm, P<0.05; 3{\mu}M: 0.61{\pm} 0.06mm, P<0.01; 5{\mu}M: 0.15{\pm}0.03 mm, P<0.01).$ Also, 4HgCl_2$decreased the percentage of rosette-forming PMNs, indicating diminished phagocytic activity of PMNs upon $HgCl_2$ exposure compared with control (control: $58{\pm}4%; 1{\mu}M: 53{\pm}4%, p<0.05; 3{\mu}M: 49{\pm}3%, P<0.01; 5{\mu}M: 46{\pm}3%, P<0.01).$ Cell viability was not antered after $HgCl_2$treatment (483{\pm}5%$ viability in control PMNs versus $81{\pm}8%$ viability in $5{\mu}M$ Hg-treated PMNs), suggesting that the impaired PMN function after $HgCl_2$treatment was not due to nonspecific cytotoxicity induced by $HgCl_2$. $HgCl_2$-induced decrease in the function of PMNs may have some implications in depressed host susceptibilityupon bacterial challenge after mercury exposure.

• Toxicological Research
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• 제34권4호
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• pp.281-290
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• 2018

Exposure to chemical agents is an inevitable consequence of modern society; some of these agents are hazardous to human health. The effects of chemical carcinogens are of great concern in many countries, and international organizations, such as the World Health Organization, have established guidelines for the regulation of these chemicals. Carcinogens are currently categorized into two classes, genotoxic and non-genotoxic carcinogens, which are subject to different regulatory policies. Genotoxic carcinogens are chemicals that exert carcinogenicity via the induction of mutations. Owing to their DNA interaction properties, there is thought to be no safe exposure threshold or dose. Genotoxic carcinogens are regulated under the assumption that they pose a cancer risk for humans, even at very low doses. In contrast, non-genotoxic carcinogens, which induce cancer through mechanisms other than mutations, such as hormonal effects, cytotoxicity, cell proliferation, or epigenetic changes, are thought to have a safe exposure threshold or dose; thus, their use in society is permitted unless the exposure or intake level would exceed the threshold. Genotoxicity assays are an important method to distinguish the two classes of carcinogens. However, some carcinogens have negative results in in vitro bacterial mutation assays, but yield positive results in the in vivo transgenic rodent gene mutation assay. Non-DNA damage, such as spindle poison or topoisomerase inhibition, often leads to positive results in cytogenetic genotoxicity assays such as the chromosome aberration assay or the micronucleus assay. Therefore, mechanistic considerations of tumor induction, based on the results of the genotoxicity assays, are necessary to distinguish genotoxic and non-genotoxic carcinogens. In this review, the concept of threshold of toxicological concern is introduced and the potential risk from multiple exposures to low doses of genotoxic carcinogens is also discussed.

• Journal of Microbiology and Biotechnology
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• 제23권9호
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• pp.1339-1346
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• 2013

Conventional chemotherapeutic regimens often accompany severe side effects and fail to induce complete regression of chemoresistant or relapsing metastatic cancers. The need for establishing more efficacious anticancer strategies led to the development of a combined modality treatment of chemotherapy in conjunction with immunotherapy or radiotherapy. It has been reported that poly-gamma-glutamate (${\gamma}$-PGA), a natural polymer composed of glutamic acids, increases antitumor activity by activating antigen-presenting cells and natural killer (NK) cells. Here, we investigated the antitumor effect of ${\gamma}$-PGA in combination with cyclophosphamide in a murine melanoma model. Whereas cyclophosphamide alone directly triggered apoptosis of tumor cells in vitro, ${\gamma}$-PGA did not show cytotoxicity in tumor cells. Instead, it activated macrophages, as reflected by the upregulation of surface activation markers and the secretion of proinflammatory factors, such as nitric oxide and tumor necrosis factor ${\alpha}$. When the antitumor effects were examined in a mouse model, combined treatment with cyclophosphamide and ${\gamma}$-PGA markedly suppressed tumor growth and metastasis. Notably, ${\gamma}$-PGA treatment dramatically increased the NK cell population in lung tissues, coinciding with decreased metastasis and increased survival. These data collectively suggest that ${\gamma}$-PGA can act as an immunotherapeutic agent that exhibits a synergistic antitumor effect in combination with conventional chemotherapy.

• The Korean Journal of Physiology and Pharmacology
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• 제17권4호
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• pp.331-338
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• 2013

AMP-activated protein kinase (AMPK), an important regulator of energy metabolism, is activated in response to cellular stress when intracellular levels of AMP increase. We investigated the neuroprotective effects of AMPK against scopolamine-induced memory impairment in vivo and glutamate-induced cytotoxicity in vitro. An adenovirus expressing AMPK wild type alpha subunit (WT) or a dominant negative form (DN) was injected into the hippocampus of rats using a stereotaxic apparatus. The AMPK WT-injected rats showed significant reversal of the scopolamine induced cognitive deficit as evaluated by escape latency in the Morris water maze. In addition, they showed enhanced acetylcholinesterase (AChE)-reactive neurons in the hippocampus, implying increased cholinergic activity in response to AMPK. We also studied the cellular mechanism by which AMPK protects against glutamate-induced cell death in primary cultured rat hippocampal neurons. We further demonstrated that AMPK WT-infected cells increased cell viability and reduced Annexin V positive hippocampal neurons. Western blot analysis indicated that AMPK WT-infected cells reduced the expression of Bax and had no effects on Bcl-2, which resulted in a decreased Bax/Bcl-2 ratio. These data suggest that AMPK is a useful cognitive impairment treatment target, and that its beneficial effects are mediated via the protective capacity of hippocampal neurons.

• BMB Reports
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• 제35권4호
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• pp.377-383
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• 2002

Arsenic trioxide ($As_O_3$) was recently demonstrated to be an effective inducer of apoptosis in patients with relapsed acute promyelocytic leukemia (APL) as well as patients with APL in whom all-trans-retinoic acid and conventional chemotherapy failed. Chronic myelogenous leukemia cells are highly resistant to chemotherapeutic drugs. To determine if $As_O_3$ might be useful for the treatment of chronic myelogenous leukemia, we examined the ability of $As_O_3$ to induce apoptosis in K562 cells. In vitro cytotoxicity of $As_O_3$ was evaluated in K562 cells by a MTT assay: the $IC_50$ value for $As_O_3$ was determined to be $10\;{\mu}m$. When analyzed by agarose gel electorphoresis, the DNA fragments became evident after incubation of the cells with $20\;{\mu}m$ $As_O_3$ for 24 h. We also found morphological changes and chromatin condensation of the cells undergoing apoptosis. Activation of caspase-3 was observed 6 h after treatment with $20\;{\mu}m$ $As_O_3$ by a Western blot analysis. Next, we examined the MAP kinase-signaling pathway of $As_O_3$-induced apoptosis in K562 cells. $As_O_3$ at $10\;{\mu}m$ strongly induced the activation of p38, inhibited $As_O_3$ induced apoptotic cell death. These results suggest that $As_O_3$ is able to induce the apoptotic activity in K562 cells, and its apoptotic mechanism may be associated with the activation of p38.

• 한국연초학회지
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• 제32권1호
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• pp.19-27
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• 2010

The aim of this study is to compare the sensitivity of both two NCI-H292 and A549 cell types to acute inflammatory responses induced by cigarette smoke. For this, we treated two kinds of smoke fractions derived from 2R4F reference cigarettes: total particulate matter(TPM) collected onto a Cambridge filter pad and gas/vapor phase(GVP) prepared by bubbling through in buffer solution. When we measured cellular cytotoxicity by neutral red uptake assay after treatment for 24 hours, TPM and GVP induced cytotoxic effect in a dose-dependent manner in the range of 10-$100{\mu}g$/mL and 60-$300 {\mu}g$/mL., respectively, in both cell types without any cellular difference. Additionally, when we examined acute inflammatory responses by analyzing cytokines secreted into culture media including tumor necrosis factor-$\alpha$ (TNF-$\alpha$), interleukin-8(IL-8), and transforming growth factor-$\alpha$(TGF-$\alpha$) as well as matrix metalloproteinase-1(MMP-1), the treatment with smoke fractions increased those marker proteins in a dose-dependent manner in NCI-H292. Meanwhile, in A549 cells only MMP-1 was observed to be increased in a dose-dependent fashion. Collectively, our data indicate that NCI-H292 cell type is more sensitive to cigarette smoke-induced inflammatory response than A549 cells. This suggests that NCI-H292 could be useful as an in vitro evaluation tool to assess harmful effects of cigarette smoke.

• Asian Pacific Journal of Cancer Prevention
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• 제16권14호
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• pp.5727-5731
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• 2015

Background: There is a long standing interest in natural compounds especially those with a high polyphenolic content and high scavenging activity for hazardous free radicals. Cornus mas (CM) fruit is well known for its antioxidant activities; however, its toxicity against human cancers needs to be addressed. Here, we investigated selective anticancer effects of CM on different human cancer cells. Materials and Methods: A hydro-alcoholic extract of CM (HECM) was prepared and total phenolic content (TPC) and total flavonoid content (TFC) were determined by colorimetric assays. Antioxidant activity was assessed with respectto DPPH radical scavenging. MTT assays were used to evaluate the cytotoxicity of different doses of CM (0, 5, 20, 100, 250, 500, $1000{\mu}g/ml$) towards A549 (lung non small cell cancer), MCF-7 (breast adenocarcinoma), SKOV3 (ovarian cancer) and PC-3 (prostate adenocarcinoma) cells. Results: Significant (P<0.05) or very significant (P<0.001) differences were observed in comparison to negative controls at all tested doses ($5-1000{\mu}g/ml$). In all cancer cells, HECM reduced the cell viability to values below 26%, even at the lowest doses. In all cases, $IC_{50}$ was obtained at doses below $5{\mu}g/ml$. The mean growth inhibition was 81.8%, 81.9%, 81.6% and 79.3% in SKOV3, MCF-7, PC-3 and A549 cells, respectively. Conclusions: Altogether, to our best knowledge, this is a first study that evaluated toxicity of a HECM with high antioxidant activity in different human cancer cells in vitro. Our results indicated that a hydro-alcoholic extract of CM possesses high potency to inhibit proliferation of different tumor cells in a dose independent manner, suggesting that an optimal biological dose is more important and relevant than a maximally tolerated one.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.2121-2127
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• 2012

Objective: Deoxyribonucleoside kinase of Drosophila melanogaster (Dm-dNK) mutants have been reported to exert suicide gene effects in combined gene/chemotherapy of cancer. Here, we aimed to further evaluate the capacity of the mutanted enzyme and its potential for inhibiting cancer cell growth. Methods: We altered the sequence of the last 10 amino acids of Dm-dNK to perform site-directed mutagenesis and constructed active site mutanted Dm-dNK (Dm-dNKmut), RT-PCR and western bloting studies were used to reveal the expression of lentivirus mediated Dm-dNKmut in a breast cancer cell line (Bcap37), a gastric cancer cell line (SGC7901) and a colorectal cancer cell line (CCL187). [3H]-labeled substrates were used for enzyme activity assays, cell cytotoxicity was assessed by MTT assays, cell proliferation using a hemocytometer and apoptosis induction by thenannexin-V-FITC labeled FACS method. In vivo, an animal study was set out in which BALB/C nude mice bearing tumors were treated with lentivirus mediated expression of Dm-dNKmut with the pyrimidine nucleoside analog brivudine (BVDU, (E)-5-(2-bromovinyl)-(2-deoxyuridine). Results: The Dm-dNKmut could be stably expressed in the cancer cell lines and retained its enzymatic activity. Moreover, the cells expressing Dm-dNKmut exhibited increased sensitivity in combination with BVDU, with induction of apoptosis in vitro and in vivo. Conclusion: These findings underlined the importance of BVDU phosphorylated by Dm-dNKmut in transduced cancer cells and the potential role of Dm-dNKmut as a suicide gene, thus providing the basis for future intensive research for cancer therapy.