• Toxicological Research
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• v.18 no.1
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• pp.99-106
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• 2002

The United States Environmental Protection Agency (EPA) characterized the cancer hazard of di(2-ethylhexyl)-phthalate (DEHP) as a B2 group (probable human carcinogen) and proposed "Guide-lines for Carcinogen Risk Assessment". This guidelines proposed alternative methods for analyzing carcinogen dose-response data and for extrapolating the effects of observed at high dose to predict that might occur at lower doses relevant to human exposure. This proposed guidelines state that "If in a particular case, the evidence indicated a threshold, as in the case of carcinogenicity being secondary to another toxicity that has a threshold, the margin of exposure analysis for toxicity is the same as is done for a non-cancer endpoint". DEHP is excellent candidate for reconideration under the new guidelines for carcinogen risk assessment (John Doull et al., 1998). This study is conducted about risk assessment for infant exposure on DEHP in powdered milk wing methodology in EPA's new guideline on carcinogenic risk assessment. Estimated cancer risk of DEHP in powdered milk and cow milk is 2.83$\times$$10^5$ (using cancer potency: 1.4$\times$$10^2$/ (mg/kg/day)) as mean and MOE is 12075 (using selected NOEL 20 mg/kg/day) as mean. mg/kg/day) as mean.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.811-816
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• 2013

Background: Pervious studies suggested occupational workers exposure to pentachlorophenol (PCP) might contribute to increased risk of cancer. However, few studies have focused on associations between PCP and cancer risk at the community level. Objective: The present study was to explore the cancer risk for the community population living long-term in a PCP contaminated area. Methods: All the cancer cases diagnosed in 2009-2011 in Tongling City were collected. The cancer patients' residencies were geo-referenced in each district. The historical PCP usage for each district of Tongling was calculated as the PCP pollution index, which was further used to divide into PCP exposure categories. Standardized rate ratios (SRRs) of cancer incidence were applied to detect the cancer risk as exposure grade elevated. Correlation analysis was performed to analyze the relationship between PCP pollution and cancer incidence. Results: A total of 5,288 cancer cases (3,451 male and 1,837 female) were identified. PCP usage was correlated with the incidence of leukemia (r=0.88, P=0.002) for males, and with cancer of the esophagus for males (r=0.83, P=0.008) and females (r=0.71, P=0.020). Compared with the low exposure category, significant SRRs for total cancer sites was obtained for high PCP exposure category (SRR=1.61, 95%CI=1.59-1.62). Most SRR values of the cancer sites were significantly increased as exposure grade elevated and exposure time extended. Conclusion: The present study found that community residents living in the PCP contaminated area had increased risk of cancers. Leukemias, lymphomas and nasopharyngeal and esophageal cancers are most possibly associated with PCP exposure.

• Journal of Radiation Protection and Research
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• v.46 no.3
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• pp.83-97
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• 2021

Background: The lifetime risk of lung cancer incidence due to radiation for nonsmokers is overestimated because of the use of the average cancer baseline risk among a mixed population, including smokers. In recent years, the generalized multiplicative (GM)-excess relative risk (ERR) model has been developed in the life span study of atomic bomb survivors to consider the joint effect of radiation and smoking. Based on this background, this paper discusses the issues of radiation risk assessment considering smoking in two parts. Materials and Methods: In Part 1, we proposed a simple method of estimating the baseline risk for nonsmokers using current smoking data. We performed sensitivity analysis on baseline risk estimation to discuss the birth cohort effects. In Part 2, we applied the GM-ERR model for Japanese smokers to calculate lifetime attributable risk (LAR). We also performed a sensitivity analysis using other ERR models (e.g., simple additive (SA)-ERR model). Results and Discussion: In Part 1, the lifetime baseline risk from mixed population including smokers to nonsmokers decreased by 54% (44%-60%) for males and 24% (18%-29%) for females. In Part 2, comparison of LAR between SA- and GM-ERR models showed that if the radiation dose was ≤200 mGy or less, the difference between these ERR models was within the standard deviation of LAR due to the uncertainty of smoking information. Conclusion: The use of mixed population for baseline risk assessment overestimates the risk for lung cancer due to low-dose radiation exposure in Japanese males.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9295-9300
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• 2014

Interleukin-17A (IL-17A) is a multifunctional cytokine which plays a crucial role in the initiation and progression of cancer. To date, several studies have investigated associations between IL-17A -197G>A (rs2275913) polymorphism and digestive cancer risk, but the results remain conflicting. We here aimed to confirm the role of this single nucleotide polymorphism (SNP) in susceptibility to digestive cancer through a systemic review and meta-analysis. Ten eligible case-control studies were identified by searching electronic databases, involving 3,087 cases and 3,815 controls. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to estimate the strength of the association. The results of overall analyses indicated that the variant A allele was associated with an increased risk of digestive cancer (AA vs GG: OR=1.51, 95%CI=1.18-1.93; AA vs GG+GA: OR=1.45, 95%CI=1.12-1.87; A vs G: OR=1.21, 95%CI=1.05-1.39). In subgroup analysis stratified by specific cancer type, elevated risk among studies of gastric cancer was found (AA vs GG: OR=1.68, 95%CI=1.24-2.28; AA vs GG+GA: OR=1.62, 95%CI=1.16-2.26; A vs G: OR=1.23, 95%CI=1.04-1.46). According to ethnicity, there was evidence in the Asian populations for an association between this polymorphism and cancer risk (GA vs GG: OR=1.19, 95%CI=1.05-1.36; AA vs GG: OR=1.56, 95%CI=1.15-2.12; AA+GA vs GG: OR=1.28, 95%CI=1.13-1.44; AA vs GG+GA: OR=1.42, 95%CI=1.01-2.00; A vs G: OR=1.24, 95%CI=1.08-1.44), while in the Caucasian populations an association was found in the recessive model (AA vs GG+GA: OR=1.62, 95%CI=1.17-2.24). In conclusion, the results of this meta-analysis suggest that the IL-17A -197G>A polymorphism contributes to an increased risk of human digestive cancer, both in the Asian and Caucasian populations and especially for gastric cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5187-5194
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• 2014

Background: Numerous studies have suggested that selenium deficiency may be associated with an increased risk for several types of cancer, but few have focused on thyroid cancer. Materials and Methods: We examined the association between post-diagnostic fingernail selenium levels and differentiated thyroid cancer risk in a French Polynesian matched case-control study. Conditional logistic regression models were used to estimate odds ratios and 95% confidence intervals. Results: The median selenium concentration among controls was $0.76{\mu}g/g$. Significantly, we found no association between fingernail selenium levels and thyroid cancer risk after conditioning on year of birth and sex and additionally adjusting for date of birth (highest versus lowest quartile: odds-ratio=1.12, 95% confidence interval: 0.66-1.90; p-trend=0.30). After additional adjustment for other covariates, this association remained non-significant (p-trend=0.60). When restricting the analysis to thyroid cancer of 10 mm or more, selenium in nails was non-significantly positively linked to thyroid cancer risk (p-trend=0.09). Although no significant interaction was evidenced between iodine in nails and selenium in nails effect (p=0.70), a non-significant (p-trend =0.10) positive association between selenium and thyroid cancer risk was seen in patients with less than 3 ppm of iodine in nails. The highest fingernail selenium concentration in French Polynesia was in the Marquises Islands ($M=0.87{\mu}g/g$) and in the Tuamotu-Gambier Archipelago ($M=0.86{\mu}g/g$). Conclusions: Our results do not support, among individuals with sufficient levels of selenium, that greater long-term exposure to selenium may reduce thyroid cancer risk. Because these findings are based on post-diagnostic measures, studies with prediagnostic selenium are needed for corroboration.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2491-2494
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• 2012

The current study was performed to assess any association between the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and risk of lung cancer in Henan province. This case-control study involved94 patients with newly histological confirmed lung cancer and 78 healthy controls. Genotyping was achieved with peripheral blood lymphocytes DNA and association of the polymorphism with risk of lung cancer was estimated by unconditional logistic regression analysis. The frequencies of the MTHFR 667TT genotype were 37.2% in cases compared with 23.1% in controls (${\chi}^2$ = 4.008, P = 0.045). Individuals with the 667CC/CT genotype displayed a significantly reduced risk of lung cancer compared with those with the TT genotypes [adjusted odds ratio (OR), 0.506; 95% confidence interval (95% CI), 0.258 - 0.991]. The C667T polymorphism might have a significant effect on the occurrence of lung cancer in Henan province.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4057-4062
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• 2012

Objective: To study the level of awareness and knowledge about cancers and associated risk factors among households in selected states of India. Methods: In the study 3070 households were interviewed from six states viz, West Bengal, Kerala, Madhya Pradesh, Rajasthan and Mizoram. Results: Knowledge of cancers other than those related to tobacco was very low (prostate 8%, colon 11% ) among the communities, with a poor awareness of warning signs and symptoms. The knowledge varied from state to state. It is found that the major source of information related to cancers was television (38%) followed by friends and relatives (36%). Only about 15 % of respondents had knowledge about cancer awareness camps organized in their districts but they did not have knowledge about the organizers of the camp. Findings suggested a strong need for strengthening of DCCP. Conclusion: It is important to create awareness among community through educational programs on cancer prevention, preventable cancer risk factors, benefits of early diagnosis, and availability of screening facilities. Integration of District Cancer Control activities with NRHM could be the most cost-effective strategy to prevent cancers and rural population.

• Journal of Nutrition and Health
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• v.38 no.2
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• pp.125-143
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• 2005

The purposes of this study were to investigate the characteristics of lifestyle and dietary habits of the colorectal cancer patients in Daegu and Kyungpook areas and to collect the data useful for nutrition education for the prevention of colorectal cancer in this community. The case subjects of the study were 123 patients diagnosed recently as colorectal cancer at Kyungpook National University Hospital. The control subjects were 182 persons who did not have any gastrointestinal diseases, including the patients from the department of orthopedic surgery and healthy volunteers. The survey covering general characteristics, life style, dietary habits, eating behaviors, and food intake frequency was administered by individual interviews using questionnaires. The results of the study suggest that high BMI, daily life stress, pessimistic personality, lack of physical activities, and familial cancer history might be the possible risk factors for the incidence of colorectal cancer. Dietary factors suspected as risk factors for colorectal cancer in the present study included strong preferences to meats, salty and fatty taste foods, low intake of water, alcohol drinking, smoking, coffee intake and irregular eating habits. A high consumption of seaweeds, green-yellow vegetables, light-colored vegetables, and green tea was suggested as a preventive factor for colorectal cancer. It is recommended to conduct more extensive and systematic surveys in the near future to reconfirm the risk factors of colorectal cancer in consideration of the characteristic food culture in this community. The results of the present study may be applied to nutritional education for the prevention of colorectal cancer for the local residents. (Korean J Nutrition 38(2): 125～143, 2005)

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5327-5332
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• 2012

In this review, we describe the patterns of known immunological components in breast milk and examine the relationship between breastfeeding and reduced risk of breast cancer. The top risk factors for breast cancer are a woman's age and family history, specifically having a first-degree relative with breast cancer. Women that have a history of breastfeeding have been shown to have reduced rates of breast cancer. Although the specific cause has not been elucidated, previous studies have suggested that breastfeeding reduces the risk of breast cancer primarily through two mechanisms: the differentiation of breast tissue and reduction in the lifetime number of ovulatory cycles. In this context, one of the primary components of human milk that is postulated to affect cancer risk is alpha-lactalbumin. Tumour cell death can be induced by HAMLET (a human milk complex of alpha-lactalbumin and oleic acid). HAMLET induces apoptosis only in tumour cells, while normal differentiated cells are resistant to its effects. Therefore, HAMLET may provide safe and effective protection against the development of breast cancer. Mothers should be encouraged to breastfeed their babies because the complex components of human milk secretion make it an ideal food source for babies and clinical evidence has shown that there is a lower risk of breast cancer in women who breastfed their babies.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.8
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• pp.3953-3958
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• 2016

Prostatic cancer is the second cause of cancer-related death among men worldwide. The human papilloma viruses (HPVs) are a family of sexually transmitted viruses which have may have roles in the ethiology of inflammation in prostate leading to benign prostatic hyperplasia (BPH) and prostate cancer (PCa). In this study, we evaluated the frequency of different HPV types in prostatic cancer and benign prostatic hyperplasia (BPH) in Kerman province, southeast of Iran, using real-time PCR techniques. The aim of the present research was to clarify any association with prostatic carcinogenesis. Real Time PCR showed that HPV DNA was found in 20% of 200 PCa samples, 80 percent of these with high-risk HPV types, 40% with type-16,18, 30 % type-31,33 and 10% type 54. High risk HPV DNA was detected in only 2% of BPH samples. Values for low risk types were much higher. Our study provided a support for the role of high risk HPV infection in prostatic disease in Iranian patients, and association between presence of HPV DNA and prostate carcinoma. In particular, HPV 16 and18 might have an important role in prostate cancer.