• Journal of Marine Bioscience and Biotechnology
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• v.1 no.2
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• pp.76-83
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• 2006

Epidemiological studies have indicated that the ubiquitous consumption of seaweeds is a protective factor against some types of cancer. Previous results showed that the administration of seaweed powder or extract reduced the incidence rate of chemically induced tumorigenesis using in vivo animal model. Recently, we reported that the extracts of Gloiopeltis furcata, a kind of Korean edible seaweed, caused he cell growth inhibition of various human cancer cell lines, among them methanol extract exhibited a relatively strong antiproliferative activity. However, the molecular mechanisms of this seaweed in malignant cells have been poorly studied until now. To elucidate this problem, we investigated the effects of methanol extract of G. furcata (MEGF) on the growth inhibition in several human cancer cell lines, and further we analyzed the effects of this extract were tested on the activity of apoptosis induction in human leukemic cells. The results demonstrated that MEGF treatment resulted in the morphological changes and the growth inhibition in a dose-dependent manner. Furthermore, MEGF potently suppresses the growth of human leukemic U937 cells by induction of apoptosis, which was associated with induction of cyclin-dependent kinase inhibitor p21(WAF1/CIP1) in a tumor suppressor p53-independent fashion and up-regulation of Fas/FasL system. Further studies will be needed to identify the active compounds that confer the anticancer activity of MEGF. Once such compounds are identified, the mechanisms by which they exert their effects can begin to be characterized.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.41-50
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• 2009

Fucoidan is a uniquely-structured sulfated fucose-rich polysaccharide derived from brown algae. Recently, the abalone glycosidase-digested fucoidan extract (fucoidan extract) derived from seaweed Cladosiphon novae-caledoniae Kylin (Mozuku) draws much attention because of its clinical anti-cancer effect in Japan. Here, we report the cancer cells-specific apoptosis inducing effects of the fucoidan extract. The fucoidan extract suppressed the growth of various anchorage-dependent and -independent cancer cells. The fucoidan extract contained low molecular weight components, which induced apoptosis of human leukemic HL 60 cells but not of human lymphocytes. It was shown that the fucoidan extract lead caspase 3/7 activation and loss of mitochondrial membrane potential in HL 60 cells. Another function of the fucoidan extract was also observed. It has been known that sugar chain expression on the surface of cancer cell membrane changes dependent on their malignancy. The analysis on sugar chain expression profiling using FITC-labeled lectins revealed that the expression of concanavalin A (Con A) binding sugar chain was enhanced by the treatment of human lung adenocarcinoma A549, human uterine carcinoma HeLa and human fibrosarcoma HT1080 cells with the fucoidan extract. Con A-induced apoptosis of cancer cells was stimulated in a dose-and time-dependent manner by the treatment with the fucoidan extract but not of human normal fibroblast TIG-1 cells.

• Proceedings of the Korean Society of Life Science Conference
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• 2006.09a
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• pp.98.2-98.2
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• 2006

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.41.2-41.2
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• 2007

See Full Text

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.42.2-42.2
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• 2007

See Full Text

• Archives of Pharmacal Research
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• v.20 no.5
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• pp.410-413
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• 1997

In the course of screening synthetic compounds to inhibit tumor cell growth, pyrrolo[1,2-.alpha.] benzimidazole (PBI), an intermediate of azamitosene, was found to inhibit a proliferation of gastric cancer cell lines. Despite a potential cytotoxic activity against solid tumor cells as opposed to that against rapidly-doubled leukemic cells, there has been no report on the inhibition of gastric cancer cell line by PBI and its' derivatives. The present experiment was designed to determine if PBI derivatives can effectively inhibit the cellular proliferation of gastric cancer cells by using in vitro as well as in vivo chemosensitivity system (MTT assay, clonogenic assay and human tumor xenografted assay). Of the tested PBI derivatives, PBI (18) and PBI (20), displayed the effective growth inhibition of cultured gastric cancer cells or even in the xenografted nude mouse model.

• Biomolecules & Therapeutics
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• v.18 no.2
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• pp.178-183
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• 2010

Costunolide is an active compound isolated from the stem bark of Magnolia sieboldii, and is considered a potential therapeutic for the treatment of various cancers. In this study, we investigated the underlying mechanism whereby costunolide induces the apoptosis of human leukemia cells. Using apoptosis analysis and quantitative reverse transcription-polymerase chain reaction (RT-PCR) results obtained during this study show that costunolide is a potent inducer of apoptosis and that it is triggered due to the premature activation of Cdc2. $G_1$-synchronized cells, which cannot undergo mitosis, were found to be more sensitive to costunolide, and Cdc2 mRNA levels were increased by costunolide treatment. Furthermore, the Cdk inhibitors, olomucine and butyrolactone I, were found to suppress costunolide-induced apoptosis. In addition, the PKC activator TPA rescued cells from cell death by costunolide, and this was prevented by the PKC inhibitor staurosporin. The present study suggests that costunolide induces the apoptosis of HL-60 leukemic cells by modulating cyclin-dependent kinase Cdc2.

• Advances in Traditional Medicine
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• v.9 no.2
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• pp.149-156
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• 2009

Equisetum hyemale Linne. (EH) (Equisetaceae) has been used for the treatment of eye and skin disease, chronic eczema, pneumoconiosis and asthma in Korea and China. Human leukemic mast cells are widely distributed in the connective tissues of mammals and other vertebrates. Phorbol 12-myristrate 13-acetate (PMA) and calcium ionophore A23187 stimulated Human leukaemic mast cell line-1 (HMC-1) can produce a variety of inflammatory mediators and several pro-inflammatory and chemotactic cytokines such as TNF-$\alpha$, IL-6 and IL-8. Since TNF-$\alpha$, IL-6 and IL-8 are major factors during the inflammatory process, we studied the effects of EH on TNF-$\alpha$, IL-6 and IL-8 release in HMC-1 stimulated with PMA and A23187. The result of this study indicate that EH inhibits TNF-$\alpha$, IL-6 and IL-8 in activated HMC-1 cells via $I{\kappa}B$/Nuclear factor-${\kappa}B$ pathway. Therefore, EH might contribute significantly to the prevention or treatment of mast-cell mediated inflammatory diseases and EH has potential use in the therapy of chronic allergic inflammation.

• Journal of Industrial Technology
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• v.25 no.B
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• pp.241-251
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• 2005

Exopolysaccharide (CBP) from submerged culture broth of Ganoderma lucidum mycelium and the water soluble (BWS) and water insoluble (BWI) fractions of CBP were prepared by gel filtration. Antitumor activity and effects on proliferation and differenciation of human cancer cells and mouse NIH 3T3 cells were studied. Cytotoxicity test of CBP, BWS and BWI fractions on human cancer cell lines was performed by using sulforhodamine B (SRB) assay. A549 (lung carcinoma), Colo320 DM and HSR (colon carcinoma), and NIH 3T3 cells were used. BWI fraction showed the strongest cytotoxicity (maximum 20% survival) to all human cells tested. However it did not induced apoptosis. Interestingly BWI fraction did not exert cytotoxic effect on NIH 3T3 cells at low concentration of cells ($5{\times}10^4$) but strong toxic effect at high concentration of cells($5{\times}10^5$) which showed transformed morphology. These results suggest that BWI may have cancer cell specific anticancer activity. However, BWI fraction did not effect the amount of pRb and c-myc protein, which implied that BWI fraction did not act at the early stage of signal transduction pathway. CBP fraction induced differenciation of human leukemic cell line, HL-60 cells suggesting the carcinogenesis prevention of normal cell and possible induction of normalization for cancer cell.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.5
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• pp.1226-1232
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• 2007

Phellinus linteus is a well-known Oriental medicinal fungus that has various biological activities, including immunomodulatory and anti-tumor activities, the mechanisms of which are poorly understood. In the present study, we investigated the anti-proliferative activity of the methanol extract of P. linteus-Barley corn (MEPLB) in human lekemic U937 cells. It was found that exposure of U937 cells to MEPLB resulted morphological change and growth inhibition in a dose-dependent manner as measured by trypan blue count and MTT assay. Upon treatment with MEPLB, U937 cells developed many of the hallmark features of apoptosis, including condensation of chromatin and an increase in the sub-G1 population suggesting that the anti-proliferative effect of MEPLB is associated with the induction of apoptosis. The anti-proliferative and apoptotic effects of MEPLB were connected with a marked induction of the pro-apoptotic Bax and cyclin-dependent kinase (Cdk) inhibitor p21 in a p53-independent manner. Additionally, MEPLB treatment significantly induced the caspase-3 activity in U937 cells. Taken together, the present results suggest that apoptotic signals evoked by MEPLB in human leukemic U937 cells may converge caspase-3 activation through an up-regulation of Bax rather than a down-regulation of Bcl-2 or Bel-xL.