• Environmental Analysis Health and Toxicology
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• v.21 no.1 s.52
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• pp.13-19
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• 2006

화학적 예방효과가 있는 식물성 에스트로젠은 다양한 환성을 나타내며 여러 세포 수용체와 상호작용한다. Genistein은 isoflavone의 주요물질 중의 하나로 콩류에 존재하며 대표적인 식물성 에스트로젠이다. 본 논문에서는 유방암 세포주인 MCF-7에서 aryl hydrocarbon receptor(AhR)에 의해 매개되는 발암물질 활성화 경로에 대한 genistein의 영향을 살펴보았다. 세포에 genistein을 처리할 경우 cytochrome P450 1A1(CYP1A1) 약물대사효소의 특이적인 효소반응인 7-ethoxyresorufin O-deethylase (EROD) 활성도와 CYP1A1의 유전자 발현이 genistein의 농도 의존적으로 증가하였다. Genistein과 발암물질인 방향족탄화 수소 7, 12-dimethylbenz[a]anthracene(DMBA)를 동시 처리하였을 경우 DMBA에 의해 유도되어 증가된 EROD활성도와 CYP1A1의 유전자 발현이 genistein에 의해 감소하였다. 랫트의 간에서 분리한 세포질을 이용하여 genistein과 AhR의 대표적인 ligand인 2,3,7,8-tetrachlorodibenzo-p-dioxin과 경쟁적 결합에 대한 영향을 조사한 결과 genistein이 AhR에 경쟁적으로 결합함을 알 수 있었다. 이러한 결과들은 genistein이 천연 AhR ligand임을 암시한다. 따라서, 식물성 에스트로젠인 genistein은 AhR경로의 길항제/항진제로 작용할 수 있을 것으로 사료된다.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.12 no.1
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• pp.27-40
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• 1990

In recent years, tissue antigens and enzymes that will serve as phenotypic markers for malignant cells are becoming increasingly important as diagnostic aids. This study was undertaken to investigate the specific activities of these enzymes in DMBA-induced rat submaxillary gland carcinogenesis. One hundred and twenty Sprague-Dawley rats about 100 gms of body weight were used. In experimental group, DMBA pellet (5mg) was implanted into right submaxillary gland and sham operation was performed into left gland to serve as control. The animals were sacrificed every three weeks up to 15 weeks. Submaxillary glands were excised on both sides and enzyme assays for ${\gamma}-glutamyl$ transpeptidase (GGT), 5'-Nucleotidase, Ornithine decarboxylase(ODC) and Acetyl-Co A carboxylase were carried out biochemically. The obtained results were as follows ; 1. In control group, there was no significant weight change of submaxillary gland, while experimental group, weight was increased remarkably about 7-fold at 15th week since DMBA implantation. 2. In control group, there was no change in specific activities of enzymes during the experimental period. 3. GGT activity was rapidly increased reaching a peak of 1.766${\pm}$0.082units/mg of DNA, 8-fold greater than that of onset. 4. 5'-Nucleotidase activity was increased reaching a peak of $362.1{\pm}53.2{\mu}moles/mg$ of DNA at 9th week. 5. ODC activity was rapidly increased, reaching a peak of 26.2${\pm}$4.8nmoles/mg of DNA at 9th week and quickly returned to that of control at 15th week. 6. Acetyl-Co A carboxylase activity was rapidly increased earlier than other enzymes, reaching a peak of 0.178${\pm}$0.013units/mg of DNA at 6th week and quickly declined to the control level at 15th week.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.2973-2978
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• 2013

Maesil (Prunus mume Siebold & Zucc.), a member of the genus Rosaceae, has been reported to have antioxidative effects, as well as anticancer influence in many cancer lines. Thus, this present study was designed to investigate the inhibitory effect of fermented Maesil with probiotics against 7,12-dimethylbenz[a]anthracene (DMBA), 12-O-tetradecanoyl phorbol 13-acetate (TPA)-induced mouse skin carcinogenesis via its antioxidative potential. Mice were fed a diet containing fermented Maesil, containing either 1% (1% FM fed group) or 2% (2% FM fed group) along with probiotics following DMBA and TPA exposure. Continuous ingestion of the experimental feed markedly inhibited skin carcinogenesis, as evidenced by a marked decrease in papilloma numbers and epidermal hyperplasia as well as cellular proliferation and the percentage of proliferating-cell nuclear antigen positive cells. Also, the FM fed group showed an increase of total antioxidant capacity as well as an increased level of phase II detoxifying enzymes such as superoxide dismutase, concurrent with a decreased lipid peroxidation activity level. Taken together, these results suggest that fermented Maesil has the ability to suppress the development of DMBA-TPA induced skin carcinogenesis, via the reduction of lipid peroxidation, enhancing total antioxidant capacity and phase II detoxifying enzyme.

• The Journal of the Korean dental association
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• v.37 no.7 s.362
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• pp.517-529
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• 1999

본 연구는 태령 19일된 백서 태자 두 개관에서 분리한 골모세포유사세포에 화학발암물질인 7,12-Dimethylbenz(a)anthracene (DMBA: 0.5 ㎍/ml) 및 tumor promotor인 12-O-tetradecanoyl-phorbol-13-acetate (TPA; 1.0 ㎍/ml)를 단독 혹은 복합 처리하여 PTRCC-DMBA, RCC-DMBA 및 RCC-DMBA-TPA 세포주를 확립시키고, 각 세포의 세포형태, 세포성장곡선, alkaline phosphatase와 acid phosphatase 활성 및 in vitro tumorigenicity를 연구하였다. 또한 c-myc, c-랜, c-jun, p53 및 Rb 유전자의 발현변화와 항암단백질인 p53 및 pRb 단백질의 발현변화를 관찰하여 골모세포유사세포가 악성형질전환되는 분자기전의 일단을 연구하고자 시행하였다. 본 실험에 사용한 모든 세포군에서 높은 aikaline phosphatase 활성과 낮은 acid phosphatase/alkaline phosphatase ratio를 보여 골모세포의 특성을 나타내었다. RCC-DMBA와 RCC-DMBA-TPA 세포는 정상세포나 PTRCC-DMBA에 비해 빠른 성장속도를 보였으며, 또한 SOFT AGAR상에서 colony를 형성하여 anchorage-independent growth를 나타내었다. 화학발암 물질로 악성변형된 세포들은 정상세포나 PTRCC-DMBA 세포에 비해 c-myc 유전자의 과발현이 관찰되었다. 정상세포에서 p53 유전자의 발현은 1.9 kb의 message만이 발현되었다. 그러나 화학발암물질로 형질전환된 세포에서는 1.9 kb message외에도 1.6 kb의 message가 더 발현되었으며, message의 양도 현저히 증가되었다. p53 단백질의 발현은 RCC-DMBA-TPA 세포에서 정상세포에 비해 현저히 감소하였으나, RCC-DMBA 세포에서는 유사한 경향을 보였다. Rb 유전자의 발현은 RCC-DMBA-TPA 세포에서만 현저히 감소하였으나, Rb 단백질의 발현은 정상세포에 비해 형질전환된 세포들에서 모두 현저히 감소되었고, 특히 RCC-DMBA-TPA 세포에서는 거의 발현되지 않았다. 이상의 결과에서 백서 태자 두 개관에서 분리한 골모세포유사세포는 화학발암물질인 DMBA에 의해 악성형질전환이 유도되었으며, c-myc의 과발현 및 p53과 Rb 단백질의 발현감소가 정상 골모세포유사세포의 악성변형과정에 밀접히 연관되어 있음을 시사한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.11 no.1
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• pp.203-220
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• 1989

Ever since the expression of new tumor-specific antigens was reported during malignant transformation, studies on separation, purification and characterization of these proteins have been so activated recently. Following experiment was performed to observe tumor-specific antigens by implanting DMBA pellet into submaxillary gland of rat for inducing salivary gland tumor. After dividing 280 rats into 2 groups, in control group, sham operation was performed on right submaxillary gland and, in experimental group, DMBA pellet (5mg) was implanted into right submaxillary gland. Then proteins from excised submaxillary gland by killing 10 rats every two weeks for 28 weeks were extracted with 3M KCl, and SDS-PAGE and PAS-staining were carried out for biochemical examination. The obtained results were summarized as follows; 1) At 12th week since implantation of DMBA pellet, tumor mass formation was inspected. And dysplasia at 6th week and invasive epidermoid carcinoma at 10th week were observed by microscope. 2) In control group, the weight ratio of both submaxillary glands had no any change, however, in experimental group, the ratio was increased remarkably. And at 28th week after DMBA implantation, there was more than 15 times of differences in weight between control and experimental group. 3) There was no DMBA remnant after 22nd experimental week. 4) In the SDS-PAGE, high molecular protein bands (more than 100 kd) were appeared much, and new prominent protein bands (66, 48, 41.5, 39, 37, 37.5 kd) were appeared after 4th week since DMBA implantation. However, 38, 27, 22kd protein bands were disappeared. 5) In PAS-staining, high molecular proteins were proteins were all glycoproteins and 37.5kd protein was proved as to be glycoprotein. And 38kd glycoprotein was disappeared after 4th week since DMBA implantation.

• Journal of Ginseng Research
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• v.39 no.3
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• pp.265-273
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• 2015

Background: Cancer has emerged as a major health problem globally as a consequence to the increased longevity of the population, changing the environment and life style. Chemoprevention is a new and promising strategy for reducing cancer burden. Recently, some natural products have been identified for their chemopreventive activity to reduce the cancer incidence. Ginseng is known for its potential to treat various ailments in human beings. The present study was designed to explore the anticancer and antioxidative potential of Panax ginseng against chemical-induced skin carcinogenesis in mammals. Methods: Skin tumors were induced in Swiss albino mice by a single topical application of 7,12-dimethylbenz(a)anthracene ($100{\mu}g/100{\mu}L$ acetone) and, 2 wks later, promoted by repeated applications of croton oil (thrice in a wk in 1% acetone) till the end of the experiment (i.e., 16 wk). Hydroalcoholic ginseng root extract at a dose of 25 mg/kg body weight/d was orally administered at the periinitiation, postinitiation, and peri-post-initiation stages. Results: Ginseng root extract treatment caused a significant reduction in tumor incidence, cumulative number of tumors, tumor yield, and tumor burden, as compared to the 7,12-dimethylbenz(a)anthracene-croton oil-treated control group. Further, biochemical assays revealed a significant enhancement in the levels of reduced glutathione, superoxide dismutase, catalase, vitamin C, and total proteins but a significant reduction in lipid peroxidation levels in both the liver and skin with ginseng root extract treatment, as compared to carcinogen-treated control group. Conclusion: These results suggest that P. ginseng has the potential to become a pivotal chemopreventive agent that can reduce cancer in mammals.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4655-4660
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• 2012

Opuntia humifusa, member of the Cactaceae family, was previously demonstrated to have radical scavenging, anti-inflammatory and anti-proliferative effects in in vitro models. It was suggested that O. humifusa could function in the prevention of carcinogenesis. To investigate the in vivo chemopreventive effect of O. humifusa, mice were fed a diet containing either 1% or 3% following 7, 12-dimethylbenz[a] anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA) induction of skin carcinogenesis. Significant decrease in the numbers of papilloma and epidermal hyperplasia were observed in mice fed with O. humifusa, compared to the control group. O. humifusa also upregulated high total antioxidant capacity and level of phase II detoxifying enzyme such as superoxide dismutase and glutathione S-transferase activity in the skin. Lipid peroxidation activity level was measured in skin cytosol and significantly inhibited in 3% OH fed group compared to the control group. These results suggest that O. humifusa exerts chemopreventive effects on chemical carcinogenesis in mouse skin and that prevention effects are associated with reduction of oxidative stress via the modulation of cutaneous lipid peroxidation, enhancing of total antioxidant capacity especially in phase II detoxifying enzyme system and partial apoptotic influence.

• Nutrition Research and Practice
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• v.9 no.6
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• pp.628-636
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• 2015

BACKGROUND/OBJECTIVES: Obesity is a risk factor of breast cancer in postmenopausal women. Estrogen deprivation has been suggested to cause alteration of lipid metabolism thereby creating a cellular microenvironment favoring tumor growth. The aim of this study is to investigate the effects of estrogen depletion in combination with excess energy supply on breast tumor development. MATERIALS/METHODS: Ovariectomized (OVX) or sham-operated C3H/HeN mice at 4 wks were provided with either a normal diet or a high-fat diet (HD) for 16 weeks. Breast tumors were induced by administration of 7,12-dimethylbenz(a)anthracene once a week for six consecutive weeks. RESULTS: Study results showed higher serum concentrations of free fatty acids and insulin in the OVX+HD group compared to other groups. The average tumor volume was significantly larger in OVX+HD animals than in other groups. Expressions of mammary tumor insulin receptor and mammalian target of rapamycin proteins as well as the ratio of pAKT/AKT were significantly increased, while pAMPK/AMPK was decreased in OVX+HD animals compared to the sham-operated groups. Higher relative expression of liver fatty acid synthase mRNA was observed in OVX+HD mice compared with other groups. CONCLUSIONS: These results suggest that excess energy supply affects the accelerated mammary tumor growth in estrogen deprived mice.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.117-123
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• 2016

Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-${\kappa}B$), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(${\alpha}$) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-${\kappa}B$, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-${\kappa}B$, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6575-6580
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• 2014

This study aimed to evaluate the antimutagenic and anticarcinogenic activity of turmeric essential oil as well as to establish biochemical mechanisms of action. Antimutagenicity testing was accomplished using strains and known mutagens with and without microsomal activation. Anticarcinogenic activity was assessed by topical application of 7, 12 - dimethylbenz[a]anthracene (DMBA) as initiator and 1% croton oil as promoter for the induction of skin papillomas in mice. Inhibition of p450 enzymes by TEO was studied using various resorufins and aminopyrene as substrate. Turmeric essential oil (TEO) showed significant antimutagenic activity (p<0.001) against direct acting mutagens such as sodium azide ($NaN_3$), 4-nitro-O-phenylenediamine (NPD) and N-methyl-N-nitro N'nitrosoguanine (MNNG). TEO was found to have significant antimutagenic effect (>90%) against mutagen needing metabolic activation such as 2-acetamidoflourene (2-AAF). The study also revealed that TEO significantly inhibited (p<0.001) the mutagenicity induced by tobacco extract to Salmonella TA 102 strain. DMBA and croton oil induced papilloma development in mice was found to be delayed and prevented significantly by TEO application. Moreover TEO significantly (P<0.001) inhibited isoforms of cytochrome p450 (CYP1A1, CYP1A2, CYP2B1/2, CYP2A, CYP2B and CYP3A) enzymes in vitro, which are involved in the activation of carcinogens. Results indicated that TEO is antimutagenic and anticarcinogenic and inhibition of enzymes (p450) involved in the activation of carcinogen is one of its mechanisms of action.