• Archives of Pharmacal Research
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• 제27권4호
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• pp.402-406
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• 2004

This research team found in previous studies, that the ginseng saponin metabolite IH901 induces apoptosis in HepG2 cells via a mitochondrial-mediated pathway, which resulted in the activation of caspase-9 and subsequently of caspase-3 and -8. Based on these results, the involvement of the Fas/Fas ligand (FasL) death-receptor pathway, in IH901-induced apoptosis in HepG2 cells, was investigated. Levels of Fas and the Fas ligand (FasL) mRNA or protein were not increased by IH901, rather they were decreased significantly at 18 h post treatment. Soluble FasL (sFasL) was detectable by immunoprecipitation analysis En the medium of HepG2 cells treated with IH901. Increased levels of sFasL were inversely correlated with the levels of FasL. Preincubation of HepG2 cells with antagonistic anti-Fas antibody showed little protective effect, if any, on IH901-induced cell death. At a $30{\mu}M$ (24 and 48 h) and $40{\mu}M$ (24 h) concentration of IH901, the cytotoxic effect of IH901 was less then $50\%$, anti-Fas antibody prevented IH901-induced cell death. However, at a $60{\mu}M$ (24 and 48 h) and $40{\mu}M$ (48 h) concentration of IH901, cell death rates were about $80\%$ or more and most of the chemopreventive and chemotherapeutic effects of IH901 were manifested. Blocking the Fas receptor did not influence IH901-induced cell death. These results indicate that the Fas/FasL system is engaged, but not required for IH901-induced cell death, at pharmacologically significant concentrations.

• IMMUNE NETWORK
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• 제13권5호
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• pp.205-212
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• 2013

Dectin-1, which specifically recognizes ${\beta}$-glucan of fungal cell walls, is a non-Toll-like receptor (TLR) pattern recognition receptor and a representative of C-type lectin receptors (CLRs). The importance of Dectin-1 in innate immune cells, such as dendritic cells and macrophages, has previously been well studied. However, the function of Dectin-1 in B cells is very poorly understood. To determine the role of Dectin-1 in B cell activation, we first investigated whether mouse B cells express Dectin-1 and then assessed the effect of Dectin-1 stimulation on B cell proliferation and antibody production. Mouse B cells express mRNAs encoding CLRs, including Dectin-1, and surface Dectin-1 was expressed in B cells of C57BL/6 rather than BALB/c strain. Dectin-1 agonists, heat-killed Candida albicans (HKCA) and heat-killed Saccharomyces cerevisiae (HKSC), alone induced B cell proliferation but not antibody production. Interestingly, HKSC, HKCA, and depleted zymosan (a selective Dectin-1 agonist) selectively enhanced LPS-driven IgG1 production. Taken together, these results suggest that, during fungal infection, ${\beta}$-glucan-stimulated Dectin-1 may cooperate with TLR4 to specifically enhance IgG1 production by mouse B cells.

• Molecules and Cells
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• 제43권5호
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• pp.459-468
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• 2020

Nuclear receptor subfamily group H member 4 (NR1H4), also known as farnesoid X receptor, has been implicated in several cellular processes in the liver and intestine. Preclinical and clinical studies have suggested a role of NR1H4 in colon cancer development; however, how NR1H4 regulates colon cancer cell growth and survival remains unclear. We generated NR1H4 knockout (KO) colon cancer cells using clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein-9 nuclease (CAS9) technology and explored the effects of NR1H4 KO in colon cancer cell proliferation, survival, and apoptosis. Interestingly, NR1H4 KO cells showed impaired cell proliferation, reduced colony formation, and increased apoptotic cell death compared to control colon cancer cells. We identified MYC as an important mediator of the signaling pathway alterations induced by NR1H4 KO. NR1H4 silencing in colon cancer cells resulted in reduced MYC protein levels, while NR1H4 activation using an NR1H4 ligand, chenodeoxycholic acid, resulted in time- and dose-dependent MYC induction. Moreover, NR1H4 KO enhanced the anti-cancer effects of doxorubicin and cisplatin, supporting the role of MYC in the enhanced apoptosis observed in NR1H4 KO cells. Taken together, our findings suggest that modulating NR1H4 activity in colon cancer cells might be a promising alternative approach to treat cancer using MYC-targeting agents.

• 셀메드
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• 제3권2호
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• pp.10.1-10.8
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• 2013

Cancer is one of the major dreaded diseases causing high mortality. Lung cancer is second in position of all cancer related deaths and mainly divided into two morphologic sub-types: small-cell lung cancer and non-small cell lung cancer (NSCLC). NSCLC is an aggressive neoplasm which hardly responds to any conventional chemotherapy. Epidermal growth factor receptor (EGFR) belongs to the ErbB family of receptor tyrosine kinase that is mainly over-expressed in NSCLC. EGFR is mainly involved in the pathogenesis and progression of different carcinoma. In vivo and in vitro studies suggest that EGFR and EGF like peptides are often over-expressed in human NSCLC and these proteins are able to induce cell transformation. The conventional therapies mostly inhibit the EGFR activity and expression level in human NSCLC with the use of some EGFR-inhibitors like HKI-272, EKB569, CL-387785 etc. and some synthetic chemotherapeutic drugs like erlotinib, gefitinib, plumbagin, docetaxel, cisplatin etc., alone or in combination of two or more drugs. These therapies selectively act by competitive inhibition of the binding of adenosine triphosphate to the tyrosine kinase domain of the EGFR, resulting in inhibition of the EGFR signaling pathway. But these chemotherapeutic drugs have some cytotoxic activities to the normal cells and have some adverse side-effects. Recent studies on some traditional alternative therapies including some herbal and plant extracts, active ingredients like curcumin, different homeopathic drugs, etc. can target EGFR-signalling in NSCLC with less toxic side-effects are being currently developed.

• Nutritional Sciences
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• 제8권3호
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• pp.159-168
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• 2005

Phytoestrogens, especially Yak-kong or soybean-derived isoflavones have been traditionally used as a supplement of estrogen for preventing postmemopausal osteoporosis in oriental folk medicine. In our previous study, the treatment of Yak-kong and soybean increased estrogen receptor-a (ERa) expression and proliferation of MG-63 osteoblastic cells. In contrast, the increase of estrogen receptor-$\beta$ (ER$\beta$) expression in proliferating MG-63 cells with Yak-kong and soybean treatment was less pronounced, which suggested that ER$\beta$ may play a role rather in the regulation of bone cell differentiation To determine the role of ER$\beta$ in Yak-kong or soybean mediated regulation of bone cell differentiation, we established MG-63 cell lines stably expressing either ER$\beta$ or antisense ER$\beta$ RNAs. Increased expression of ER$\beta$ did not affect ERa expression and proliferation of MG-63 cells. However, increased expression of ER$\beta$ in MG-63 cells (ER$\beta$-MG63 cells) selectively enhanced Yak-kong or soybean induced expression of osteoprotegerin (OPG), a novel soluble glycoprotein which is secreted from osteoblasts and mediates the signal for osteoclast differentiation. Inhibition of ER$\beta$ expression by antisense ER$\beta$ RNAs (As-ER$\beta$-MG63) caused these cells to insensitize Yak-kong or soybean induced expression of OPG but increased MG-63 cell proliferation. Furthermore, the comparable effects between Yak-kong and the combined treatment of genistein and daidzein at $0.5{\times}l0^{-8}$ M, which is a concentration of these two isoflavones similar to Yak-kong at 0.001 mg/mL, on OPG expression in ER$\beta$-MG63 cell demonstrate that the enhanced expression of OPG with Yak-kong treatment is mediated by the synergistic effect of low leveled isoflavones in the extracts. Together, coupled with low level of ER expression in osteoclasts, our data demonstrate that ER$\beta$ in osteoblasts plays an important role in Yak-kong and soybean mediated inhibition of osteoclast differentiation indirectly by enhancing the expression of OPG.

• Biomolecules & Therapeutics
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• 제26권3호
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• pp.322-327
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• 2018

A type of breast cancer with a defect in three molecular markers such as the estrogen receptor, progesterone receptor, and human epidermal growth factor receptor is called triple-negative breast cancer (TNBC). Many patients with TNBC have a lower survival rate than patients with other types due to a poor prognosis. In this study, we confirmed the anti-cancer effect of a natural compound, Gomisin G, in TNBC cancer cells. Treatment with Gomisin G suppressed the viability of two TNBC cell lines, MDA-MB-231 and MDA-MB-468 but not non-TNBC cell lines such as MCF-7, T47D, and ZR75-1. To investigate the molecular mechanism of this activity, we examined the signal transduction pathways after treatment with Gomisin G in MDA-MB-231 cells. Gomisin G did not induce apoptosis but drastically inhibited AKT phosphorylation and reduced the amount of retinoblastoma tumor suppressor protein (Rb) and phosphorylated Rb. Gomisin G induced in a proteasome-dependent manner a decrease in Cyclin D1. Consequently, Gomisin G causes cell cycle arrest in the G1 phase. In contrast, there was no significant change in T47D cells except for a mild decrease in AKT phosphorylation. These results show that Gomisin G has an anti-cancer activity by suppressing proliferation rather than inducing apoptosis in TNBC cells. Our study suggests that Gomisin G could be used as a therapeutic agent in the treatment of TNBC patients.

• Parasites, Hosts and Diseases
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• 제53권4호
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• pp.431-438
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• 2015

In Trichinella spiralis infection, type 2 helper T (Th2) cell-related and regulatory T ($T_{reg}$) cell-related immune responses are the most important immune events. In order to clarify which Toll-like receptors (TLRs) are closely associated with these responses, we analyzed the expression of mouse TLR genes in the small intestine and muscle tissue during T. spiralis infection. In addition, the expression of several chemokine- and cytokine-encoding genes, which are related to Th2 and $T_{reg}$ cell mediated immune responses, were analyzed in mouse embryonic fibroblasts (MEFs) isolated from myeloid differentiation factor 88 (MyD88)/TIR-associated proteins (TIRAP) and Toll receptor-associated activator of interferons (TRIF) adapter protein deficient and wild type (WT) mice. The results showed significantly increased TLR4 and TLR9 gene expression in the small intestine after 2 weeks of T. spiralis infection. In the muscle, TLR1, TLR2, TLR5, and TLR9 gene expression significantly increased after 4 weeks of infection. Only the expression of the TLR4 and TLR9 genes was significantly elevated in WT MEF cells after treatment with excretory-secretory (ES) proteins. Gene expression for Th2 chemokine genes were highly enhanced by ES proteins in WT MEF cells, while this elevation was slightly reduced in MyD88/$TIRAP^{-/-}$ MEF cells, and quite substantially decreased in $TRIF^{-/-}$ MEF cells. In contrast, IL-10 and $TGF-{\beta}$ expression levels were not elevated in MyD88/$TIRAP^{-/-}$ MEF cells. In conclusion, we suggest that TLR4 and TLR9 might be closely linked to Th2 cell and $T_{reg}$ cell mediated immune responses, although additional data are needed to convincingly prove this observation.

• Molecules and Cells
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• 제42권12호
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• pp.869-883
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• 2019

Interleukin (IL)-15 is an essential immune-modulator with high potential for use in cancer treatment. Natural IL-15 has a low biological potency because of its short half-life and difficulties in mass-production. IL-15Rα, a member of the IL-15 receptor complex, is famous for its high affinity to IL-15 and its ability to lengthen the half-life of IL-15. We have double-transfected IL-15 and its truncated receptor IL-15Rα into CT26 colon cancer cells to target them for intracellular assembly. The secreted IL-15:IL-15Rα complexes were confirmed in ELISA and Co-IP experiments. IL-15:IL-15Rα secreting clones showed a higher anti-tumor effect than IL-15 secreting clones. Furthermore, we also evaluated the vaccine and therapeutic efficacy of the whole cancer-cell vaccine using mitomycin C (MMC)-treated IL-15:IL-15Rα secreting CT26 clones. Three sets of experiments were evaluated; (1) therapeutics, (2) vaccination, and (3) long-term protection. Wild-type CT26-bearing mice treated with a single dose of MMC-inactivated secreted IL-15:IL-15Rα clones prolonged survival compared to the control group. Survival of MMC-inactivated IL-15:IL-15Rα clone-vaccinated mice (without any further adjuvant) exceeded up to 100%. This protection effect even lasted for at least three months after the immunization. Secreted IL-15:IL-15Rα clones challenging trigger anti-tumor response via CD4⁺ T, CD8⁺ T, and natural killer (NK) cell-dependent cytotoxicity. Our result suggested that cell-based vaccine secreting IL-15:IL-15Rα, may offer the new tools for immunotherapy to treat cancer.

• Journal of Ginseng Research
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• 제44권4호
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• pp.593-602
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• 2020

Background: Heat stress orchestrates neurodegenerative disorders and results in the formation of reactive oxygen species that leads to cell death. Although the immunomodulatory effects of ginseng are well studied, the mechanism by which ginseng alleviates heat stress in the brain remains elusive. Methods: Rats were exposed to intermittent heat stress for 6 months, and brain samples were examined to elucidate survival and antiinflammatory effect after Korean Red Ginseng (KRG) treatment. Results: Intermittent long-term heat stress (ILTHS) upregulated the expression of cyclooxygenase 2 and inducible nitric oxide synthase, increasing infiltration of inflammatory cells (hematoxylin and eosin staining) and the level of proinflammatory cytokines [tumor necrosis factor α, interferon gamma (IFN-γ), interleukin (IL)-1β, IL-6], leading to cell death (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay) and elevated markers of oxidative stress damage (myeloperoxidase and malondialdehyde), resulting in the downregulation of antiapoptotic markers (Bcl-2 and Bcl-x_L) and expression of estrogen receptor beta and brain-derived neurotrophic factor, key factors in regulating neuronal cell survival. In contrast, KRG mitigated ILTHS-induced release of proinflammatory mediators, upregulated the mRNA level of the antiinflammatory cytokine IL-10, and increased myeloperoxidase and malondialdehyde levels. In addition, KRG significantly decreased the expression of the proapoptotic marker (Bax), did not affect caspase-3 expression, but increased the expression of antiapoptotic markers (Bcl-2 and Bcl-x_L). Furthermore, KRG significantly activated the expression of both estrogen receptor beta and brain-derived neurotrophic factor. Conclusion: ILTHS induced oxidative stress responses and inflammatory molecules, which can lead to impaired neurogenesis and ultimately neuronal death, whereas, KRG, being the antioxidant, inhibited neuronal damage and increased cell viability.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권2호
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• pp.66-73
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• 2009

Tumor angiogenesis is a process leading to formation of blood vessels within tumors and is crucial for maintaining a supply of oxygen and nutrients to support tumor growth and metastasis. Vascular endothelial growth factor(VEGF) plays a key role in tumor angiogenesis including induction of endothelial cell proliferation, migration, survival and capillary tube formation. VEGF binds to two distinct receptors on endothelial cells. VEGFR-2 is considered to be the dominant signaling receptor for endothelial cell permeability, proliferation, and differentiation. Bevacizumab(Avastin, Genetech, USA) is a monoclonal antibody against vascular endothelial growth factor. It is used in the treatment of cancer, where it inhibits tumor growth by blocking the formation of new blood vessels. The goal of this study is to identify the anti-tumor effect of Bevacizumab(Avastin) for oral squamous cell carcinoma cell lines. Human squamous cell carcinoma cell line(HN4) was used in this study. We examined the sensitivity of HN4 cell line to Bevacizumab(Avastin) by using in vitro proliferation assays. The results were as follows. 1. In the result of MTT assay according to concentration of Bevacizumab(Avastin), antiproliferative effect for oral squamous cell carcinoma cell lines was observed. 2. The growth curve of cell line showed the gradual growth inhibition of oral squamous cell carcinoma cell lines after exposure of Bevacizumab(Avastin). 3. In the apoptotic index, groups inoculated Bevacizumab(Avastin) were higher than control groups. 4. In condition of serum starvation, VEGFR-2 did not show any detectable autophosphorylation, whereas the addition of VEGF activated the receptor. Suppression of phosphorylated VEGFR-2 and phosphorylated MAPK was observed following treatment with Bevacizumab(Avastin) in a dose-dependent manner. 5. In TEM view, dispersed nuclear membrane, scattered many cytoplasmic vacuoles and localized chromosomal margination after Bevacizumab(Avastin) treatment were observed. These findings suggest that Bevacizumab(Avastin) has the potential to inhibit MAPK pathway in proliferation of oral squamous cell carcinoma cell lines via inhibition of VEGF-dependent tumor growth.