• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.81-81
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• 2002

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.291.3-292
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• 2002

Cancer is multifaceted disease that presents many challenges to clinicians and cancer researchers searching for more effective ways to combat its often devastating effects. Among the central challenges of this disease, are the identification of markers for improved diagnosis and classification of tumors, and the definition of targets for more effective therapeutic measures. The objective of this study is to identify potential biomarkers for the early detection of gastric cancer in serum. (omitted)

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7561-7566
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• 2015

Ziziphus jujuba (ZJ) fruit is rich in bioactive functional components such as polysaccharides, triterpenoid acid, flavonoids and oleamide. It has been commonly used in the treatment of various diseases including diabetes, digestive disorders, diarrhea, skin infections, liver and urinary diseases. However, its dietary effect on chemoprevention of colon cancer has never been studied. The present study was to evaluate the protective effects of dietary ZJ on colitis-associated colon carcinogenesis in azoxymethane (AOM)-dextran sodium sulphate (DSS)-treated mice. AOM was injected (10 mg/kg b.wt., i.p.) and three cycles of 2% DSS in drinking water for 7 days with 14 days of normal drinking water in-between was administered to induce colitis-associated colon cancer. ZJ fruit was supplemented in feed as 5 and 10%. Dietary ZJ significantly attenuated aberrant crypt foci (ACF) formation thereby decreasing the progression of hyperplasia to dysplasia. In addition, it significantly reduced circulating white blood cells, lymphocytes, neutrophils, monocytes, eosinophils, basophils and platelets compared to colon cancer mice. We conclude that ZJ supplementation delayed the progression of colon cancer from hyperplasia to dysplasia and ultimately adenocarcinoma and cancer. In addition, it decreased circulating tumor-related leucocytes, main regulators of cancer inflammation. Therefore, dietary consumption of ZJ fruit attenuated the formation of ACF and delayed the progression of colon cancer.

• Environmental Mutagens and Carcinogens
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• v.18 no.1
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• pp.9-14
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• 1998

By far, the largest known preventable cause of cancer is cigarette smoking. The percentage of cancer deaths in Korea due to tobacco is still increasing. Smoking cigarette at an early age has become more common among women. Tobacco consumption is related causally to cancer to the lung, mouth, larynx, esophagus, bladder, kidney, uterine cervix, and pancreas. Recently, several studies demonstrated that there is very strong correlation between cigarette smoking and p53 mutations in lung cancer, head and neck cancer, and bladder cancer. The recent findings of cigarette smoking and cancer, p53 and bcl-2 mutations, adverse effects of smoking on the effects of radiotherapy, and benefits of quitting will be discussed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.23
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• pp.10107-10114
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• 2015

MicroRNA-27a is highly expressed in cancers and has been identified as an oncogenic microRNA. A genetic variant in pre-miR-27a (rs895819) with a transition of A to G has been demonstrated to be associated with cancer risk; however, the results of these studies remain conflicting rather than conclusive. Therefore, we performed a meta-analysis to derive a more precise estimation. Through searching PubMed or other databases up to March 2014 using the following MeSH terms and keywords, "miR-27a", "polymorphism" and "cancer", seventeen case-control studies were identified in this meta-analysis, including 7,813 cases and 9,602. Crude odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were calculated to investigate the association strength between rs895819 and the susceptibility of cancer. The results of the overall meta-analysis did not suggest any association between rs895819 polymorphism and cancer susceptibility, and this remained in Asians as a subgroup. In Caucasians, however, the rs895819 was associated with a reduced cancer risk in heterozygous (OR, 0.83; 95%CI, 0.75-0.93) and dominant models (OR, 0.84; 95%CI, 0.76-0.93), and the [G] allele of rs895819 showed a protective effect (OR, 0.90, 95%CI, 0.84-0.97). Further studies showed a significant association between the [G] allele of rs895819 and decreased risk of breast cancer (0.91; 95%CI, 0.85-0.98), and stratified analyses indicated a protective effect of the [G] allele in Caucasians (OR, 0.89; 95%CI, 0.82-0.98), younger breast cancer cases (OR, 0.87; 95%CI, 0.79-0.96), and in the group of unilateral breast cancer patients (OR, 0.90; 95%CI, 0.83-0.97). These findings suggest an association between pre-miR-27a polymorphism rs895819 and cancer risk in Caucasians. The protective effect of rs895819 [G] allele in younger breast cancer and in the group of unilateral breast cancer patients await further confirmation since the included studies in this meta-analysis were limited.

• Environmental Analysis Health and Toxicology
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• v.10 no.1_2
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• pp.21-35
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• 1995

Risk assessment processes, which include processes for the estimation of human cancer potency using animal bioassay data and calculation of human exposure, entail uncertainties. In the exposure assessment process, exposure scenarios with various assumptions could affect the exposure amount and excess cancer risk. We compared risk estimates among various exposure scenarios of vinyl chloride, trichloroethylene and tetrachloroethylene in tap water. The contaminant concentrations were analyzed from tap water samples in Seoul from 1993 to 1994. The oral and inhalation cancer potencies of the contaminants were estimated using multistage, Weibull, lognormal, and Mantel-Bryan model in TOX-RISK computer software. In the first case, human excess cancer risk was estimated by the US EPA method used to set the MCL(maximum contaminant level). In the second and third case, the risk was estimated for multi-route exposure with and without adopting Monte-Carlo simulation, respectively. In the second case, exposure input parameters and cancer potencies used probability distributions, and in the third case, those values used point estimates(mean, and maximum or 95% upper-bound value). As a result, while the excess cancer risk estimated by US EPA method considering only direct ingestion tended to be underestimated, the risk which was estimated by considering multi-route exposure without Monte-Carlo simulation and then using the maximum or 95% upper-bound value as input parameters tended to be overestimated. In risk assessment for volatile organic compounds, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.

• 대한예방의학회:학술대회논문집
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• 1995.10a
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• pp.73-74
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• 1995

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.282.2-283
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• 2002

In situ and circulating estrogen is the most important endocrine hormone that promotes the growth of hormone-dependent breast cancer. Consequently. decrease of estrogen on in situ and circulation can inhibit breast cancer. Estrogen is mainly produced by the ovary in premenopausal women and by peripheral tissues such as adipose tissues in postmenopausal women. The cytochrome p450 (CYP19), aromatase. is a key enzyme in the synthesis of estrogen hormones. (omitted)

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.162-162
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• 2001

Phytoestrogens produced naturally by either plants or their seeds are three main classes of phytoestrogens: isoflavone, lignan and coumestan. Phytoestrogens can have both agonist and antagonist action of estrogenic activity. It is believed that phytoestrogens with agonist and antagonist action of estrogenic activity may reduce the risk of breast cancer, in addition to may reduce the risk of osteoporesis by therapeutic agent of breast cancer.(omitted)

• Journal of Environmental Health Sciences
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• v.40 no.5
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• pp.385-396
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• 2014

Objectives: By conducting a meta-analysis of cohort studies reporting standardized mortality ratios (SMRs) for workers exposed to trichloroethylene, we attempted to adjust for healthy hired effect by applying the same methods as described in a recent report from the Agricultural Health Study. Methods: Among all cohort studies that evaluated the association between all cancer, non-Hodgkin's lymphoma (NHL), kidney cancer, liver cancer and occupational exposure to trichloroethylene, a total of 10 studies reporting SMR values were selected. A random-effects model was used to estimate the summary SMRs or rSMRs and 95% confidence intervals. Relative SMR ($rSMR=SMR_x/SMR_{not\;x}$) was calculated comparing observed and expected counts for all cancer, NHL, kidney cancer, and liver cancer with an independent referent set of values consisting of the observed and expected counts for other causes. Results: The SMR values for all causes ranged from 0.68 to 1.03, suggesting moderate to weak healthy worker effect for the selected studies. When the healthy worker hire effect was taken into account, the summarized risk became statistically significant; the summary SMR of all cancer was 0.95 (0.91-1.00) and the summary rSMR of all cancer was 1.10 (1.04-1.15). The summary SMR of NHL was 1.04 (0.93-1.14) and the summary rSMR of NHL was 1.23 (1.04-1.46). The summary SMR of kidney cancer was 1.08 (0.88-1.33) and the summary rSMR of kidney cancer was 1.23 (1.02-1.49). The summary SMR of liver cancer was 0.88 (0.78-0.99), and the summary rSMR of liver cancer was 0.95 (0.84-1.07). Conclusion: The rSMR method is useful to determine summary risk adjusted for healthy worker effect through meta-analysis.