• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Effects of Edible Phytochemicals and Their Synthetic Derivatives on Carcinogenesis and Mutagenesis
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• pp.15-15
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• 2001

In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz［$\alpha$］anthracene (DMBA).(omitted)

• 한국독성학회:학술대회논문집
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• 한국독성학회 2001년도 International Symposium on Dietary and Medicinal Antimutgens and Anticarcinogens
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• pp.58-58
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• 2001

In the present study, we examined the chemopreventive effects of indole-3-carbinol (I3C), a constituent of cruciferous vegetables (the Family of Cruciferae) such as cabbages, cauliflowers and broccoli on multiple intestinal neoplasia (Min) genetic mouse model and on mouse colon carcinogenesis induced by azoxymethane (AOM) as well as on rat mammary carcinogenesis induced by 7, 12-dimethybenz［$\alpha$］anthracene (DMBA).(omitted)

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2005년도 Proceedings of The 2nd Asian Society of Veterinary Pathology Symposium(Vol.2) and 2005 Annual Meeting of The Korean Society of Veterinary Pathology(Vol.9)
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• pp.81-82
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• 2005

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.118-118
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• 2003

The influence of dietary supplementation with dehydroepiandrosterone-sulphate (DHEA-S) at 0.6% was investigated in male Syrian golden hamsters initiated by treatments with azoxymethane(AOM), and dihydroxy-di-n-propyl nitrosamine (DHPN), timed after transfer from a choline-deficient to a normal diet.(omitted)

• 한국식품위생안전성학회지
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• 제25권3호
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• pp.269-277
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• 2010

본 연구에서는 azoxymethane (AOM)과 dextran sodium sulfate (DSS)로 유도된 대장 발암과정에 대한 셀레늄의 방어 효과를 조사하였다. 셀레늄 결핍(0.02 ppm Se), 정상(0.1 ppm Se), 과다(0.5 ppm Se)사료를 12주간 식이로 급여하여 혈액검사와 대장암 발생의 초기단계인 aberrant crypt foci (ACF)수를 측정했으며, 암 발생율을 조사하였다. ICP-AES를 사용하여 간의 셀레늄 농도를 측정하였으며, 또한 셀레늄포함 항산화효소인 glutathione peroxidase (GPx) 활성을 알아보았다. 또한 TUNEL assay와 PCNA, $\beta$-catenin에 대한 면역조직 염색을 수행하였다. ACF 수 및 종양 발생률에 있어서, 셀레늄과다사료를 급여한 군이 정상셀레늄사료를 급여한 군보다 낮았으며, 셀레늄결핍사료를 급여한 군은 오히려 ACF 수 및 종양 발생률이 높았다. GPx 활성은 셀레늄의 섭취가 과다한 군에서 높게 나타났으며, 이 때, TUNEL에서 apoptotic positive cell이 증가하는 것을 확인했다. 또한 셀레늄의 섭취가 과다한 군에서 PCNA와 $\beta$-catenin의 발현이 감소됨을 볼 수 있었다. 본 마우스 모델실험에서 셀레늄은 여러 기전에 의해 대장암 발생을 억제할 수 있을 것으로 사료된다.

• 대한한방내과학회지
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• 제38권6호
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• pp.863-876
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• 2017

Objectives: The aim of this experimental study was to evaluate the anti-neoplastic and anti-inflammatory effects of single and mixed extracts of Ulmus davidiana (UD) and Oldenlandia diffusa (OD) on azoxymethane/dextran sodium sulfate (AOM/DSS)-induced colonic neoplasms in mice. Methods: AOM/DSS induces colitis-associated colonic neoplasms in mice. Mice were divided into seven groups: normal-no inducement and no treatment; control-colonic neoplasms with no treatment; UD-colonic neoplasms and treatment with UD; OD-colonic neoplasms and treatment with OD; UD1+OD1-colonic neoplasms and treatment with UD1 and OD1. UD1+OD2-colonic neoplasms and treatment with UD1 and OD2; UD2+OD1-colonic neoplasms and treatment with UD2 and OD1. Single and mixed preparations of UD and OD were applied to mice for six weeks. The colon length and weight and histopathologic changes of colon tissue were observed. Serum pro-inflammatory cytokines, including tumor necrosis factor-alpha ($TNF-{\alpha}$) and interleukin-6 (IL-6), were determined by enzyme-linked immunosorbent assay. The mRNA expression levels of Bax, Bcl-2, and interferon-gamma ($INF-{\gamma}$) were measured by RT-PCR. Results: The colon length was significantly increased in OD, UD1+OD2, and UD2+OD1 mice, and the colon weight was significantly decreased in OD and UD1+OD2 mice. The morphological change of colon epithelial cells was more suppressed in complex-treatment groups than in single-treatment groups. The inhibitory effect on inflammatory cell invasion was especially shown in UD1+OD2 mice. The serum level of the pro-inflammatory $TNF-{\alpha}$ was decreased in all complex-treatment groups, and the IL-6 level was decreased in UD1+OD1 mice. Single-treatment groups had an increase in the mRNA expression of the pro-apoptosis regulator Bax, and UD2+OD1 decreased the mRNA expression of the anti-apoptosis regulator Bcl-2. The mRNA expression of $INF-{\gamma}$ associated with inflammation was decreased in OD and UD1+OD2 mice. Conclusions: This study suggests that single and mixed extracts of Ulmus davidiana and Oldenlandia diffusa have anti-neoplastic and anti-inflammatory effects on AOM/DSS-induced colonic neoplasms in mice. Therefore, we conclude that UD, OD, and a mixture of UD and OD are potential therapeutic agents for colitis-associated colonic neoplasms.

• 대한수의학회지
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• 제48권3호
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• pp.337-345
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• 2008

There are accumulating evidences that high levels of dietary iron may play a role in colon carcinogenesis. Elevated iron status has been associated with oxidative stress. Phytic acid (PA) functions as an antioxidant by chelating divalent cations and prevents formation of reactive oxygen species responsible for cell injury and carcinogenesis. The protective effect of PA was investigated on formation of aberrant crypt foci (ACF) induced by azoxymethane (AOM) in iron-overloaded male F344 rats. After acclimation with AIN-93G purified diet (35 ppm Fe, normal control diet) for one week, animals were fed iron-overloaded diet (350 ppm Fe) and PA (0.5% or 2% PA in water) for 8 weeks. Animals received two (1st and 2nd week) injections of AOM (15 mg/kg b.w.) to induce colonic ACF. The colonic mucosa was examined for the total numbers of aberrant crypt (AC) and ACF after staining with methylene blue. The blood and serum were analyzed with a blood cell differential counter and an automatic serum analyzer. Iron-overloaded diet increased the concentration of iron in liver of the rats. But iron-related parameters in blood were not changed among experimental groups. The numbers of ACF per colon and AC per colon were $178.8{\pm}33.2$ and $448.4{\pm}110.2$ in the iron-overloaded F344 rats. The total AC was significantly increased, compared with normal-diet AOM control group (p < 0.05). The treatments of PA at the dose of 0.5% slightly decreased the number of ACF and AC per colon to $153.6{\pm}29.5$ and $396.3{\pm}107.5$. However, there were no significant differences in the total numbers of ACF and AC between the AOM control group and PA (0.5% or 2%)-treated groups. These results suggest that PA may not affect the formation of ACF or AC induced by AOM in ironoverloaded F344 rats.

• Asian Pacific Journal of Cancer Prevention
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• 제16권2호
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• pp.683-687
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• 2015

Aloe vera gel exhibits protective effects against insulin resistance as well as lipid-lowering and anti-diabetic effects. The anti-diabetic compounds in this gel were identified as Aloe-sterols. Aloe vera gel extract (AVGE) containing Aloe-sterols has recently been produced using a new procedure. We previously reported that AVGE reduced large-sized intestinal polyps in Apc-deficient Min mice fed a high fat diet (HFD), suggesting that Aloe vera gel may protect against colorectal cancer. In the present study, we examined the effects of Aloe vera gel powder (AVGP) and AVGE on azoxymethane-induced colorectal preneoplastic aberrant crypt foci (ACF) in mice fed a HFD. Male C57BL/6J mice were given a normal diet (ND), HFD, HFD containing 0.5% carboxymethyl cellulose solution, which was used as a solvent for AVGE (HFDC), HFD containing 3% or 1% AVGP, and HFDC containing 0.0125% (H-) or 0.00375% (L-) AVGE. The number of ACF was significantly lower in mice given 3% AVGP and H-AVGE than in those given HFD or HFDC alone. Moreover, 3% AVGP, H-AVGE and L-AVGE significantly decreased the mean Ki-67 labeling index, assessed as a measure of cell proliferation in the colonic mucosa. In addition, hepatic phase II enzyme glutathione S-transferase mRNA levels were higher in the H-AVGE group than in the HFDC group. These results suggest that both AVGP and AVGE may have chemopreventive effects on colorectal carcinogenesis under the HFD condition. Furthermore, the concentration of Aloe-sterols was similar between 3% AVGP and H-AVGE, suggesting that Aloe-sterols were the main active ingredients in this experiment.

• Asian Pacific Journal of Cancer Prevention
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• 제13권8호
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• pp.4067-4073
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• 2012

Obesity is an established risk factor for colorectal cancer. Pioglitazone is a peroxisome proliferator activated receptor$receptor{\gamma}$ ($PPAR{\gamma}$) agonist that induces differentiation in adipocytes and induces growth arrest and/or apoptosis in vitro in several cancer cell lines. In the present study, we investigated the effect of pioglitazone on the development of azoxymethane-induced colon aberrant crypt foci (ACF) in KK-$A^{\mathcal{Y}}$ obesity and diabetes model mice, and tried to clarify mechanisms by which the $PPAR{\gamma}$ ligand inhibits ACF development. Administration of 800 ppm pioglitazone reduced the number of colon ACF/mouse to 30% of those in untreated mice and improved hypertrophic changes of adipocytes in KK-$A^{\mathcal{Y}}$ mice with significant reduction of serum triglyceride and insulin levels. Moreover, mRNA levels of adipocytokines, such as leptin, monocyte chemoattractant protein-1 and plasminogen activator inhibitor-1, in the visceral fat were decreased. PCNA immunohistochemistry revealed that pioglitazone treatment suppressed cell proliferation in the colorectal epithelium with elevation of p27 and p53 gene expression. These results suggest that pioglitazone prevented obesity-associated colon carcinogenesis through improvement of dysregulated adipocytokine levels and high serum levels of triglyceride and insulin, and increase of p27 and p53 mRNA levels in the colorectal mucosa. These data indicate that pioglitazone warrants attention as a potential chemopreventive agent against obesity-associated colorectal cancer.

• 한국식품위생안전성학회지
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• 제26권4호
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• pp.388-397
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• 2011

Selenium (Se) is known to prevent from several cancers, while iron (Fe) is known to be associated with high risk of cancers. The role of Se on colon carcinogenesis was investigated in an animal model induced by azoxymethane (AOM) and dextran sodium sulfate (DSS) in low Fe mice. Six-week old ICR mice fed on a low Fe diet (4.5 ppm Fe; generally 10 times lower than normal Fe) with three different Se (0.02, 0.1 or 0.5 ppm) levels for 24 weeks. The animals received weekly three ($0{\sim}2^{nd}$ weeks) i.p. injections of AOM (10 mg/kg RW), followed by 2% DSS with drinking water for 1 week to induce the colon cancer. There were five experimental groups including vehicle, positive control (normal Fe level, AOM/DSS), Low Fe (LFe) + AOM/DSS+Low Se (LSe), LFe + AOM/DSS + medium Se (MSe) and LFe + AOM/DSS + high Se (HSe) groups. HSe group showed a 66.7% colonic tumor incidence, MSe group showed a 69.2% tumor incidence, and LSe group showed a 80.0% tumor incidence. The tumor incidence was negatively associated with Se levels of diets. Tumor multiplicity in Hse group was significantly low compared to the other groups (p < 0.05). With increasing Se levels of diets, the primary anti-proliferating cell nuclear antigen (PCNA)-positive cells were decreased and apoptotic bodies were increased in a dose-dependent manner. Se-dependent glutathione peroxidase activity and its protein level were dependent on the levels of Se of diets. Malondialdehyde level in liver was lowest in Hse group among experimental groups. These findings indicate that dietary Se is chemopreventive for colon cancer by increasing antioxidant activity and decreasing cell proliferation in Fe-deficient mice.