• Title/Summary/Keyword: tumor inhibition

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Anti-angiogenic Activity of Ursolic Acid (우르솔릭산의 혈관형성 억제활성)

  • 손경희;이옥희;이열남;정해영;이정준;김규원
    • YAKHAK HOEJI
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    • v.37 no.5
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    • pp.532-537
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    • 1993
  • Angiogenesis refers to the formation of new capillary blood vessels, or neovascularization occurring under various physical conditions, such as development of the embryo, formation of corpus luteum, wound healing and pathological conditions including tumor growth and metastases, hemangiomas, diabetic retinopathy, rheumatoid arthritis. There are many evidences that angiogenesis is important for the progressive growth of solid tumors and also permits the shedding of metastatic tumors from the primary site. Thus, treatment of angiogenesis inhibitors might be a novel strategy for tumor growth inhibition. Normal vascular endothelial cells are in a state of differentiation and angiogenic endothelial cells migrate and proliferate, and they subsequently differentiate into vessel-forming quiescent phenotype cells, Therfore, it was speculated that a modifier of cell differentiation could also affect angiogenesis. In order to identify new antiangiogenic factors, the research was conducted to estimate the inhibitory activities of cell differentiation agents by means of chick embryo chorioallantoic membrane(CAM) assay. Hence, we have established the CAM assay for the screening of antiangiogenic agents. Using the CAM assay, we found that ursolic acid, a tumor cell differentiation-inducing agent, showed a markedly inhibitory effect on chick embryonic angiogenesis.

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Studies on the Antineoplastic Components of Korean Basidiomycetes (한국산(韓國産) 담자균류(擔子菌類) 항암(抗癌) 성분(成分)에 관한 연구(硏究))

  • Kim, Byong-Kak;Chung, Hee-Soo;Chung, Kyung-Soo;Yang, Moon-Sik
    • The Korean Journal of Mycology
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    • v.8 no.2
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    • pp.107-113
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    • 1980
  • To investigate antitumor components of Korean higher fungi, the carpophores of Ganoderma lucidum (Fr.)Karst. were collected at Gal-mae-ri in Gyeong-gi Province and extracted with 0.1N sodium hydroxide solution. The extract was purified by dialyzing through Visking tube and a dark brownish power was obtained. The antitumor activity of the fraction was tested against sarcoma 180 implanted in mice. The tumor inhibition ratio of the fraction against the tumor was 87.6% in doses of 50 mg/kg/day for the period of ten days. The tumor in five of 15 mice was completely regressed. The antitumor fraction was chemically analyzed and found to be a complex of polysaccharide and protein, from which four monosaccharides and eighteen amino acids were identified.

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Differential Antitumor Activities of the Proteoglycans from the Mycelium of Lentinus Lepideus (잣버섯 균사체로부터 분리한 단백다당체의 암종에따른 선별적 항암작용)

  • Jin, Mi-Rim;Jung, Kyu-Sun;Kim, Byong-Kak
    • YAKHAK HOEJI
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    • v.42 no.5
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    • pp.480-486
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    • 1998
  • Many antitumor and immune modulating components have been isolated from fungal extracts. In this study, the authors isolated the proteoglycans from cultured mycelia of Lentin us lepideus, including especially the acidic polysaccharide fraction, named lepidan. It was obtained by extraction with hot water followed by purification using DEAE cellulose anion exchange. To elucidate antitumor effects against different type of tumor, the proteoglycans were tested on sarcoma 180, C3H MCA clone 16 and P388 leukemia in vivo. Lepidan showed 58.3% of tumor inhibition against solid form of sarcoma 180 and 58.6% against MCA clone 16. But lepidan did not affect life span of mice against P388 leukemia. Also when Lepidan was applicated to MTT assay, it did not show any direct cytotoxicity against various tumor cells in vitro.

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Cryptotanshinone Induces Inhibition of Breast Tumor Growth by Cytotoxic CD4+ T Cells through the JAK2/STAT4/ Perforin Pathway

  • Zhou, Jun;Xu, Xiao-Zhen;Hu, Yao-Ren;Hu, Ai-Rong;Zhu, Cheng-Liang;Gao, Guo-Sheng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2439-2445
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    • 2014
  • Cryptotanshinone (CPT), is a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miotiorrhiza bunge. Numerous researchers have found that it could work as a potent antitumor agent to inhibit tumor growth in vitro, buith there has been much less emphasis on its in vivo role against breast tumors. Using a mouse tumor model of MCF7 cells, we showed that CPT strongly inhibited MCF7 cell growth in vivo with polarization of immune reactions toward Th1-type responses, stimulation of naive CD4+ T cell proliferation, and also increased IFN-${\gamma}$ and perforin production of CD4+ T cells in response to tumor-activated splenocytes. Furthermore, data revealed that the cytotoxic activity of CD4+ T cells induced by CPT was markedly abrogated by concanamycin A(CMA), a perforin inhibitor, but not IFN-${\gamma}$ Ab. On the other hand, after depletion of CD4+ T cells or blocked perforin with CMA in a tumor-bearing model, CPT could not effectively suppress tumor growth, but this phenomenon could be reversed by injecting naive CD4+ T cells. Thus, our results suggested that CPT mainly inhibited breast tumor growth through inducing cytotoxic CD4+ T cells to secrete perforin. We further found that CPT enhanced perforin production of CD4+ T cells by up-regulating JAK2 and STAT4 phosphorylation. These findings suggest a novel potential therapeutic role for CPT in tumor therapy, and demonstrate that CPT performs its antitumor functions through cytotoxic CD4+ T cells.

Inhibition of Tumor Invasion and Metastasis by Calcium Spirulan(Ca-SP), a Novel Sulfated Polysaccharide Derived from a Blue-Green Alga Spirulina Platensis

  • Saiki, Ikuo;Murata, Jun;Fujii, Hideki;Kato, Toshimitsu
    • Nutritional Sciences
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    • v.7 no.3
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    • pp.144-150
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    • 2004
  • We have investigated the effect of calcium spirulan(Ca-SP) isolated from a blue-green alga Spirulina platensis, which is a sulfated polysaccharide chelating calcium and mainly composed of rhamnose and fructose, on invasion of both B16- BL6 melanoma cells, Colon 26 carcinoma and HT-1080 fibrosarcoma cells through reconstituted basement membrane (Matrigel). Ca-SP significantly inhibited the invasion of these tumor cells through Matrigel/fibronectin-coated filters in a concentration-dependent manner. Ca-SP also inhibited the haptotactic migration of tumor cells to laminin, but it had no inhibitory effect on tumor cell migration to fibronectin-coated filters. Ca-SP prevented the adhesion of B16-BL6 cells to Matrigel- and laminin-substrates but did not affect the adhesion to fibronectin. The pretreatment of tumor cells with Ca-SP inhibited the adhesion to laminin in a concentration-dependent fashion, while the pretreatment of laminin-substrates did not. Ca-SP had no effect on the production and activation of type IV collagenase in gelatin zymography. In contraset, Ca-SP significantly inhibited degradation of heparan sulfate by purified heparanase. The experimental lung metastasis was significantly reduced by co-injection of B16-BL6 cells with Ca-SP in a dose-dependent manner. Seven intermittent ⅰ.ⅴ. injection of 100$\mu\textrm{g}$ of Ca-SP caused a marked decrease of lung tumor colonization of B16-BL6 cells in a spontaneous lung metastasis model. These results suggest that Ca-SP, a novel sulfated polysaccharide, could reduce the lung colonization of B16-BL6 melanoma cells in experimental metastasis model, by inhibiting the tumor invasion of basement membrane Matrigel, probably through the prevention of the adhesion and migration of tumor cells to laminin-substrate and of the heparanase activity.

Tumor Growth Inhibitory and Immunomodulatory Activities of Cordyceps Militaris Water Extracts in ICR Mice Bearing Sarcoma-180 Solid Tumor (누에번데기 및 누에애벌레 밀리타리스동충하초(Cordyceps militaris) 열수추출물의 투여가 고형암이 유발된 마우스의 종양성장 억제 및 면역기능에 미치는 영향)

  • 이해미;이여진;박태선
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.1
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    • pp.59-65
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    • 2004
  • Hot water-extracts prepared from Cordyceps militaris of silkworm pupa (CMP) or Cordyceps militaris of silkworm larva (CML) were tested for tumor growth inhibitory and immunomodulatory activities in ICR mice bearing sarcoma-180 cells solid tumor, and compared with those of the known compound, cordycepin, found in Cordyceps militaris. Mice were subcutaneously injected with sarcoma-180 cells, and i.p. injected with either saline (Control), 50 mg/kg or 100 mg/kg of CMP (CMP50 or CMP100, respectively), or CML (CML50 or CML100, respectively), or 1 or 2 mg/kg of cordycepin (C1 or C2, respectively) for 10 days. Mice injected with CMP50 or CMP100 showed a 47.3% or 57.6% inhibition in the solid tumor growth (P<0.05), while those injected with CML50 or CML100 exhibited a 35.5% or 37.1% reduction (p<0.05) in solid tumor size compared to the value for control mice treated with saline. Animals injected with corcycepin showed a 26∼30% inhibition in the solid tumor growth (P<0.05). Mice bearing solid tumor and injected with CMP or CML showed a significantly increased thymus weight (38∼44% increase), lymphocyte percentages of CD4+ T-cell, CD8+ T-cell, and NK-cell (63∼110% increase) in the spleen, and interleukin-2 excretion (33∼51% increase) by the isolated splenocytes compared to those in control mice (p<0.05). These results indicate that the anti-tumor activity of hot water extracts of Cordyceps militaris, raised on both silkworm pupa and silkworm larva, appears to be associated with their immunomodulatory activity, and these activities found in Cordyceps militaris are superior to those for the single compound, cordycepin.

Immunostimulation Effects of Cell Wall Components Isolated from Lactobacillus plantarum

  • TAE BOO CHOE;KANG, KWAN YUEB;SUNG HO PARK
    • Journal of Microbiology and Biotechnology
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    • v.4 no.3
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    • pp.195-199
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    • 1994
  • Immunostimulation effects of the cell wall components isolated from Lactobacillus plantarum were investigated by studying the macrophage s tumorcidal activity, splenocyte proliferation, anticomplementary activity and the inhibition of peritoneal tumor cell growth measured with ICR mice inoculated with sarcoma 180. The immunopotentiating cell wall components were a complex of peptidoglycan and exopolysaccharides. The tumorcidal activity of macrophage against Yacl and B16 tumor cells was enhanced when the cell wall components were added into the macrophage s culture medium. They also stimulated splenocytes to proliferate up to the same level as when the concanavalin A was added into the splenocyte's culture medium. The complementary activity was inhibited by 50% when the cell wall components were incubated with the sheep red blood cells treated with hemolysin and guinea pig complement. This result confirmed that the cell wall components had an antitumor effect, because the anticomplementary activity is usually accompanied by an antitumor activity at the same time. This fact was confirmed again by the inhibition of the growth of sarcoma 180 when the cell wall components were injected intraperitoneally into ICR mice inoculated with sarcoma 180. As a result, it is concluded that the cell wall components isolated from Lactobacillus plantarum had multifunctional immunostimulation effects in vitro and in vivo.

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Toll-like Receptor 5 Agonist Inhibition of Growth of A549 Lung Cancer Cells in Vivo in a Myd88 Dependent Manner

  • Zhou, Shi-Xiang;Li, Feng-Sheng;Qiao, Yu-Lei;Zhang, Xue-Qing;Wang, Zhi-Dong
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2807-2812
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    • 2012
  • The purpose of this study was to examine the effect of a Toll-like receptor 5 (TLR5) agonist, CBLB502, on the growth and radiosensitivity of A549 lung cancer cells in vivo. Expression of myeloid differentiation factor 88 (MyD88) or TLR5 was stably knocked down in human lung cancer cells (A549) using lentivirus expressing short hairpin RNA targeting human MyD88 or TLR5. Lack of MyD88 or TLR5 expression enhanced tumor growth in mouse xenografts of A549 lung cancer cells. CBLB502 inhibited the growth of A549 lung cancer cells, not A549-MyD88-KD cells in vivo in the murine xenograft model. Our results showed that the inhibition of A549 by CBLB502 in vivo was realized through regulating the expression of neutrophil recruiting cytokines and neutrophil infiltration. Finally, we found that activation of TLR5 signaling did not affect the radiosensitivity of tumors in vivo.

ATF3 Activates Stat3 Phosphorylation through Inhibition of p53 Expression in Skin Cancer Cells

  • Hao, Zhen-Feng;Ao, Jun-Hong;Zhang, Jie;Su, You-Ming;Yang, Rong-Ya
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.12
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    • pp.7439-7444
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    • 2013
  • Aim: ATF3, a member of the ATF/CREB family of transcription factors, has been found to be selectively induced by calcineurin/NFAT inhibition and to enhance keratinocyte tumor formation, although the precise role of ATF3 in human skin cancer and possible mechanisms remain unknown. Methods: In this study, clinical analysis of 30 skin cancer patients and 30 normal donors revealed that ATF3 was accumulated in skin cancer tissues. Functional assays demonstrated that ATF3 significantly promoted skin cancer cell proliferation. Results: Mechanically, ATF3 activated Stat3 phosphorylation in skin cancer cell through regulation of p53 expression. Moreover, the promotion effect of ATF3 on skin cancer cell proliferation was dependent on the p53-Stat3 signaling cascade. Conclusion: Together, the results indicate that ATF3 might promote skin cancer cell proliferation and enhance skin keratinocyte tumor development through inhibiting p53 expression and then activating Stat3 phosphorylation.

Effects of Seman Armenicae and Radix Trichosanthis on the iNOS expression and superoxide formation in the RAW264.7 cells (행인 과루인 추출물이 마우스 대식세포주인 RAW264.7 세포주의 iNOS 발현 및 Superoxide 형성에 미치는 영향)

  • Park, Joug-Un;Moon, Seok-Jae;Moon, Goo;Won, Jin-Hee
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.5 no.1
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    • pp.137-150
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    • 1999
  • Macrophage play a major role in host defence against infection and tumor development and this activity is regulated through the production of several mediators. In particular, the production of NO by macrophages mediates killing or growth inhibition of tumor cells, bacteria, fungi and parasites. However, over-expression of iNOS by various stimuli, resulting in over-production of NO, contributes to the pathogenesis of septic shock and some inflammator and auto-immune disease. Therefore, it would be valuable to develop potent and selective inhibitors of for potential therapeutic use. Thus the agent that supprees the expression of iNOS mRNA or enzyme protein will be usefull for the prevention of various diseases. We are intersted in identifying selective inhibitiors of iNOS which might be useful intreating inflammatory human diseases. In summary, we have demenstrated that scopoletin, isolated from Seman Armenicae and Radix Trichosanthis the production of NO induced by $IFN-\gammer$ plus LPS in RAW 264.7 macrophages, The mechanism for the inhibition of NO production was due to suppression of the expression of iNOS mRNA or enzyme protein.

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