• IMMUNE NETWORK
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• v.21 no.6
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• pp.44.1-44.15
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• 2021

Tumor peptides associated with MHC class I molecules or their synthetic variants have attracted great attention for their potential use as vaccines to induce tumor-specific CTLs. However, the outcome of clinical trials of peptide-based tumor vaccines has been disappointing. There are various reasons for this lack of success, such as difficulties in delivering the peptides specifically to professional Ag-presenting cells, short peptide half-life in vivo, and limited peptide immunogenicity. We report here a novel peptide vaccination strategy that efficiently induces peptide-specific CTLs. Nanoparticles (NPs) were fabricated from a biodegradable polymer, poly(D,L-lactic-co-glycolic acid), attached to H-2K^b molecules, and then the natural peptide epitopes associated with the H-2K^b molecules were exchanged with a model tumor peptide, SIINFEKL (OVA_257-268). These NPs were efficiently phagocytosed by immature dendritic cells (DCs), inducing DC maturation and activation. In addition, the DCs that phagocytosed SIINFEKL-pulsed NPs potently activated SIINFEKL-H2K^b complex-specific CD8⁺ T cells via cross-presentation of SIINFEKL. In vivo studies showed that intravenous administration of SIINFEKL-pulsed NPs effectively generated SIINFEKL-specific CD8⁺ T cells in both normal and tumor-bearing mice. Furthermore, intravenous administration of SIINFEKL-pulsed NPs into EG7.OVA tumor-bearing mice almost completely inhibited the tumor growth. These results demonstrate that vaccination with polymeric NPs coated with tumor peptide-MHC-I complexes is a novel strategy for efficient induction of tumor-specific CTLs.

• Korean Journal of Pharmacognosy
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• v.45 no.2
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• pp.174-180
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• 2014

D-Pinitol, an anti-diabetic substance, is a naturally occurring compound found in legumes. In this study, we investigated the inhibitory effect of D-pinitol on growth and recurrence of breast cancer. When D-pinitol was treated on MDA-MB-231 or MCF-7 breast cancer cells, it was observed that the viability of the two cancer cell lines was reduced in MTT assay. In order to examine the effect on the growth of breast tumor, mouse xenograft assay was carried out. On day 0, nine millions cells of MDA-MB-231 were injected subcutaneously into nude mouse and D-pinitol was administered orally at the dose of 500 mg/kg or 1000 mg/kg body weight for consecutive 45 days. Tumor size was reduced in dose-dependent manner upto 95.4% in 1000 mpk-treated group, compared with the non-treated control group. When D-pinitol was co-administrated with $4{\mu}g$ of doxorubicin, recurrence of breast tumor was delayed by two weeks, compared with the mouse group of doxorubicin monotherapy. Consistent with this data, it was observed that the population of cancer stem cells (CSCs), responsible for recurrence of cancer, within tumor mass was significantly reduced. Taken together, D-pinitol inhibits the growth of breast cancer and relapse of the tumor by suppressing the proliferation of CSCs.

• BMB Reports
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• v.48 no.3
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• pp.127-128
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• 2015

Tumor metastasis involves circulating and tumor-initiating capacities of metastatic cancer cells. Hepatic TM4SF5 promotes EMT for malignant growth and migration. Hepatocellular carcinoma (HCC) biomarkers remain unexplored for metastatic potential throughout metastasis. Here, novel TM4SF5/CD44 interaction-mediated self-renewal and circulating tumor cell (CTC) capacities were mechanistically explored. TM4SF5-dependent sphere growth was correlated with $CD133^+$, $CD24^-$, ALDH activity, and a physical association between CD44 and TM4SF5. The TM4SF5/CD44 interaction activated c-Src/STAT3/ Twist1/ B mi1 signaling for spheroid formation, while disturbing the interaction, expression, or activity of any component in this signaling pathway inhibited spheroid formation. In serial xenografts of less than 5,000 cells/injection, TM4SF5-positive tumors exhibited locally-increased CD44 expression, suggesting tumor cell differentiation. TM4SF5-positive cells were identified circulating in blood 4 to 6 weeks after orthotopic liver-injection. Anti-TM4SF reagents blocked their metastasis to distal intestinal organs. Altogether, our results provide evidence that TM4SF5 promotes self-renewal and CTC properties supported by $CD133^+/TM4SF5^+/CD44^+^{(TM4SF5-bound)}/ALDH^+/CD24^-$ markers during HCC metastasis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1502-1506
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• 2006

To investigate the inhibitory effects of Citaowan (CTW) on the growth and angiogenesis of breast cancer in vivo. Orthotopic breast cancer model was established by injection of MDA-MB-231 cells into mammary fat pad of nude mice. Seven weeks after injection, CTW was orally administered at dose of 50, 100 mg/mouse every day for 40 days. Body weight, tumor volume, tumor apoptosis, microvessel density and tumor proliferation were evaluated, after the mice were sacrificed. The body weight and tumor volume were not significantly changed in CTW group compared with the control group. Tumor apoptosis, proliferation and microvessel density were significantly reduced in CTW group (100 mg/mouse) compared with the control group. These data indicate that CTW has anti-angiogenic and proapoptotic effects on breast cancer.

• Korean Journal of Pharmacognosy
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• v.25 no.3
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• pp.249-257
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• 1994

The cytotoxic and antitumor activity of Perilla frutescens extract on cultured 3T3 fibroblast and skin melanoma cells were evaluated by tetrazolium MTT (MTT) and neutral red (NR) colorimetric assay methods. Lactate dehydrogenase activity was also measured. The light microscopic study was carried out to observe morphological changes of cultured mouse fibroblast and skin melanoma cells. The results were as follows: 1. Water and ether extracts showed a significant cytotoxicity in 3T3 fibroblast and all extracts exhibited a significant anti-tumor activity in skin melanoma cells. Methanol, ethyl acetate and ethanol extracts showed low cytotoxic effects, but exhibited a high anti-tumor activity. 2. The MTT absorbance in 3T3 fibroblast was significantly decreased by treatment with ether, water, chloroform and ethanol extracts and skin melanoma cells was significantly decreased by treatment with all extracts. The difference in MTT absorbance in two cell types was most remarkable when treated with methanol and ethanol extracts. 3. Methanol and ethyl acetate extracts showed the strongest effect in growth inhibition of melanoma cells. These results indicated that methanol extract possessed a low cytotoxicity and a strong anti-tumor activity.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.218-222
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• 2009

Ability of water extract from Prunella vulgaris Labiatae to stimulate immune system and inhibit tumor metastasis in mice was assessed. In experimental lung metastasis, prophylactic intravenous (i.v.) administration of water extract from P. vulgaris significantly inhibited lung metastasis in a dose-dependant manner. Peritoneal macrophages stimulated with P. vulgaris produced various cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interlukin (IL)-12 as well as induced tumoricidal activity. In an assay for natural killer (NK) cell activity, i.v. administration of P. vulgaris significantly augmented NK cytotoxicity. The depletion of NK cells by injection of rabbit anti-asialo GM1 serum abolished the inhibitory effect of P. vulgaris on lung metastasis of colon26-M3.1 cells. These data demonstrate that P. vulgaris activate innate immune system to inhibit the growth of foreign materials including tumor cells in mice.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6219-6225
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• 2014

Background: Increasing evidence from animal, epidemiological and clinical investigations suggest that dietary anthocyanins have potential to prevent chronic diseases, including cancers. It is also noteworthy that human epidermal growth factor receptor 2 (ErbB2) protein overexpression or ErbB2 gene amplification has been included as an indicator for metastasis and higher risk of recurrence for breast cancer. Materials and Methods: The present experiments investigated the anti-metastasis effects of black rice anthocyanins (BRACs) on ErbB2 positive breast cancer cells in vivo and in vitro. Results: Oral administration of BRACs (150 mg/kg/day) reduced transplanted tumor growth, inhibited pulmonary metastasis, and decreased lung tumor nodules in BALB/c nude mice bearing ErbB2 positive breast cancer cell MDA-MB-453 xenografts. The capacity for migration, adhesion, motility and invasion was also inhibited by BRACs in MDA-MB-453 cells in a concentration dependent manner, accompanied by decreased activity of a transfer promoting factor, urokinase-type plasminogen activator (u-PA). Conclusions: Together, our results indicated that BRACs possess anti-metastasis potential against ErbB2 positive human breast cancer cells in vivo and in vitro through inhibition of metastasis promoting molecules.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.4
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• pp.338-342
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• 2004

This study was performed to measure the antioxidant effects of red ginseng extracts which antioxidation had been promoted through enzyme hydrolysis. In order to observe their tumor-suppressing effects, an anti-cancer medicine and Saponin-SOD, which was a highly antioxidant beverage made from red ginseng saponin adding SOD-like rice (with embryo buds) extracts, were administered to nude mice with large intestine cancer induced. There was a significant increase in the content of phenolic compounds as the enzyme was added. The red ginseng extracts showed a high electron-donating ability with the passage of time. The electron-donating ability was particularly high in the enzyme-treated red ginseng extract, and also observed as high in Saponin-SOD. The lipid-peroxide generation was inhibited depending on the concentration of Saponin-SOD added; the addition of 0.625% Saponin-SOD served to decrease the inhibition level up to 65% compared with the case of no addition (100%). As a result, it could be assumed that Saponin-SOD would strongly inhibit the oxidation of ghost membrane. After the cancer was induced in nude mice through the injection of SNUC-4 cell, there was a significant inhibition in the growth of tumors in nude mice into which Saponin-SOD were injected; the growth of tumors was gradually decreasing with the passage of time after the cancer induction. In particular, when Saponin-SOD was administered together with an anti-cancer medicine, the synergic effect was observed. In conclusion, Saponin-SOD, when used with an anti-cancer medicine, is expected to reduce the amount of free radical and lipid peroxide, which are known to cause harmful effects occurring from the internal application of medicine.

• International Journal of Oncology
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• v.54 no.6
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• pp.2117-2126
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• 2019

Transforming growth factor-β1 (TGF-β1) is a multifunctional cytokine that functions as a growth suppressor in normal epithelial cells and early stage tumors, but acts as a tumor promoter during malignant progression. However, the molecular basis underlying the conversion of TGF-β1 function remains largely undefined. X-linked inhibitor of apoptosis-associated factor 1 (XAF1) is a pro-apoptotic tumor suppressor that frequently displays epigenetic inactivation in various types of human malignancies, including colorectal cancer. The present study explored whether the anti-apoptotic effect of TGF-β1 is linked to its regulatory effect on XAF1 induction in human colon cancer cells under stressful conditions. The results revealed that TGF-β1 treatment protected tumor cells from various apoptotic stresses, including 5-fluorouracil, etoposide and γ-irradiation. XAF1 expression was activated at the transcriptional level by these apoptotic stresses and TGF-β1 blocked the stress-mediated activation of the XAF1 promoter. The study also demonstrated that mitogen-activated protein kinase kinase inhibition or extracellular signal-activated kinase (Erk)1/2 depletion induced XAF1 induction, while the activation of K-Ras (G12C) led to its reduction. In addition, TGF-β1 blocked the stress-mediated XAF1 promoter activation and induction of apoptosis. This effect was abrogated if Erk1/2 was depleted, indicating that TGF-β1 represses XAF1 transcription through Erk activation, thereby protecting tumor cells from apoptotic stresses. These findings point to a novel molecular mechanism underlying the tumor-promoting function of TGF-β1, which may be utilized in the development of a novel therapeutic strategy for the treatment of colorectal cancer.

• Parasites, Hosts and Diseases
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• v.52 no.6
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• pp.605-612
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• 2014

Toxoplasma gondii is an intracellular protozoan parasite that causes a Th1 cellular immunity. Our previous study showed that T. gondii lysate antigen (TLA) treatment in S180 tumor-bearing mice resulted in tumor reduction by suppressing CD31 expression, a marker of angiogenesis. In the present study, to investigate tumor suppressive effect of TLA under the absence of T lymphocytes, athymic nude mice were compared with euthymic mice in the anti-tumorigenic effect triggered by TLA in CT26 tumors. According to the results, intratumorally injected TLA reduced tumor growth and TIMP-1 level, a metastatic marker, in both euthymic and athymic mice. TLA treatment led to a sharp increase in IL-12 expression in serum cytokine profiling of athymic mice, and increased MyD88 signals in macrophages derived from the bone marrow, implying the activation of innate immunity. The selective induction of IL-12 by TLA treatment had an anti-tumorigenic effect.