• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4927-4935
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• 2015

Northeastern India is a major nasopharyngeal carcinoma (NPC) high risk-area although the rest of the country has very low incidence. A case-control study of 105 NPC cases and 115 controls was conducted to identify the potential risk factors for NPC development in this region. Information was collected by interviewer about socio-demographic characteristics, cigarette smoking, alcohol consumption, dietary history, occupational history, and a family history of cancer. Epstein-Barr viral load was assayed from the blood DNA by real time PCR. Associations between GSTs genotypes, cytochrome P450 family including CYP1A1, CYP2E1 and CYP2A6 polymorphisms and susceptibility to relationship between the diseases were studied using PCR-RFLP assay. Results indicate that Epstein-Barr virus load was significantly higher in patients compared to controls (p<0.0001). Furthermore, concentration of blood EBV-DNA was significantly higher in advanced stage disease (Stage III and IV) than in early stage disease (Stage I and II) (p<0.05). Presence of CYP2A6 variants that reduced the enzyme activity was significantly less frequent in cases than controls. Smoked meat consumption, exposure to smoke, living in poorly ventilated house and alcohol consumption were associated with NPC development among the population of Northeastern India. Thus, overall our study revealed that EBV viral load and genetic polymorphism of CYP2A6 along with living practices which include smoked meat consumption, exposure to smoke, living in poorly ventilated houses and alcohol consumption are the potential risk factors of NPC in north eastern region of India. Understanding of the risk factors and their role in the etiology of NPC are helpful forpreventive measures and screening.

• Environmental Analysis Health and Toxicology
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• v.12 no.3_4
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• pp.31-41
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• 1997

Public concerns about hazardous health effect from the exposure to organic by-products of the chlorination have been increased. There are numerous studies reporting that chlorination of drinking water produces numerous chlorinated organic by-products including THMs, HAAs, HANs. Some of these products are known to be animal carcinogens. The purpose of this study was to estimate health risk of DBPs by chlorinated drinking water ingestion in Seoul based on methodologies that have been developed for conducting risk assessment of complex-chemical-mixture. The drinking water sample was collected seperately at six water treatment plant in Seoul at March, April, 1996. In tap water of households in Seoul, DBPs were measured wilfh the mean value of 36.6 $\mu$g/L. 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. The reference dose of haloacetonitriles was estimated to be 0.0023 mg/kg/day by applying dibromoacetonitrile NOAEL and uncertainty factor to the mean concentration. 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 Trihalomethanes, considering multi-route exposure with adopting Monte-Carlo analysis seems to provide the most reasonable estimations.

• Journal of Soil and Groundwater Environment
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• v.28 no.6
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• pp.33-44
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• 2023

A risk assessment on the heavy metals including arsenic (As), cupper (Cu), lead (Pb), and zinc (Zn) was investigated by setting exposure routes in agricultural fields. Moreover, the factors requiring improvement in risk assessment were also discussed through a review of the dermal absorption slope factor (SF_abs) and total amount of suspended particles (TSP) in the current risk assessment guidelines. Assessment results show that the total cancer risk (TCR) of As through crop and soil ingestion was 1.51E-03 in adults and 6.37E-4 in children, which indicated a carcinogenic risk (exceeding 1E-05). On the other side, the harzard index (HI) was 3.37 in adults and 1.41 in children, which was evaluated as having a non-carcinogenic risk (>1). The carcinogenic purification targets for As were calculated to be 6.84 mg/kg in adults and 6.86 mg/kg in children, while the non-carcinogenic purification targets were calculated to be 13.43 mg/kg for adults and 22.54 mg/kg for children. When applying SF_abs 61 of the current guidelines, it appears that there is a carcinogenic risk even though the As exposure concentration is below the area of concern 1 standard (25 mg/kg), which suggestes that additional research on this factor is required for the risk assessment. In order to apply the measured suspended particle concentration to risk assessment, TSP should be derived from PM10 using an appropriate correlation equation. As a result, it is suggested to improve the risk assessment guidelines so that the mesured PM10 value measured in the field can be used directly.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6475-6479
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• 2012

Background: Recent studies have demonstrated an association between insulin growth factor (IGF) and insulin growth factor binding protein-3 (IGFBP-III) serum levels and increased risk for various cancers. However, little information is available on clinical implications of the IGF system in Indian patients with cervical cancer. This study explored associations by analyzing their expression profiles in cervical cancer cases. Materials and Methods: Totals of 50 patients with advanced cervical cancer and 40 healthy controls were enrolled. Human papillomavirus (HPV) and cervical biopsy sample were obtained from all participating women. Circulatory levels were estimated by ELISA and the tissue expression was assessed using RT-PCR and Western blotting. Results: Levels of IGF-I and II showed significant increase whereas IGFBP-III showed significant decline in all patients as compared to controls. Spearman correlation analysis between IGFs and HPV status showed significant correlations. Conclusions: We demonstrated elevated circulating levels and tissue expression of IGF-I and IGF-II in advancer cancer cervix patients, as compared with controls, with a converse trend being apparent for IGFBP-III. In future, associations of the IGF system and clinical outcome of cervical cancer patients in post treatment samples might point to significance in disease mapping as a prognostic marker after validation with a larger patient series.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4289-4294
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• 2014

Background: One of the most important reasons for the high mortality rates of cancer is the low level of awareness, which can lead to a late diagnosis and treatments starting too late. Therefore, it is necessary for individuals, especially at younger age, to gain awareness and integrate taking the necessary precautions into their lifestyle in order to prevent cancer and ensure early diagnosis. The aim of this study was to assess the levels of awareness of factors for major cancers among students studying in two different campuses of a university in the Western Black Sea Region. Materials and Methods: This descriptive/cross-sectional study was performed between January-March 2014. Students studying in the 2013-2014 academic year in a university in the Western Black Sea Region in two separate campuses were the subjects. Results: The mean age was $21.01{\pm}3.63$. While female students (51.2%) were the majority in the health sciences campus (74.8%), male students (48.8%) were the majority in the social sciences campus (76.5%). Some 9.6% of the students from the health sciences campus and 12.4% of the students from the social sciences campus thought that cancer was communicable, while most of the students from both campuses knew that smoking caused cancer. It can also be seen that the rate of answering questions regarding cancer correctly was higher among students studying in the health sciences campus. Conclusions: It was determined that students who do not study at the health sciences campus have insufficient information on cancer, cancer symptoms, and the possibility of breast cancer in males and approximately half of them regarded obesity as a risk factor for cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5219-5223
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• 2013

The number of axillary lymph nodes involved and retrieved are important prognostic factors in breast cancer. The purpose of our study was to investigate whether the lymph node ratio (LNR) is a better prognostic factor in predicting disease-free survival (DFS) for breast cancer patients as compared with pN staging. The analysis was based on 804 breast cancer patients who had underwent axillary lymph node dissection between 1999 and 2008 in Sun Yat-Sen University Cancer Center. Optimal cutoff points of LNR were calculated using X-tile software and validated by bootstrapping. Patients were then divided into three groups (low-, intermediate-, and high-risk) according to the cutoff points. Predicting risk factors for relapse were performed according to Cox proportional hazards analysis. DFS was estimated using the Kaplan-Meier method and compared by the log-rank test. The 5-year DFS rate decreased significantly with increasing LNRs and pN. Univariate analysis found that the pT, pN, LNR, molecule type, HER2, pTNM stage and radiotherapy well classified patients with significantly different prognosis. By multivariate analysis, only LNR classification was retained as an independent prognostic factor. Furthermore, there was a significant prognostic difference among different LNR categories for pN2 category, but no apparent prognostic difference was seen between different pN categories in any LNR category. Therefore, LNR rather than pN staging is preferable in predicting DFS in node positive breast cancer patients, and routine clinical decision-making should take the LNR into consideration.

• Korean Journal of Psychosomatic Medicine
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• v.20 no.2
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• pp.82-90
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• 2012

Objectives : Though gastric cancer is one of the most common cancer in Korea, there have been few studies to explore psychological distress in gastric cancer. The purpose of this study was to investigate the prevalence and associated risk factors of psychological distress among patients with gastric cancer. Methods : With consecutive sampling, a total of 274 patients with gastric cancer who admitted to a cancer center in a general hospital were recruited and assessed on psychological distress using the Hospital Anxiety and Depression Scale(HADS). Sociodemographic and cancer-related clinical variables were also evaluated. Results : One hundred fifty-three(55.8%) patients with gastric cancer showed psychological distress. Logistic regression models revealed that having alcohol drinking experience[odds ratio(OR)=2.10, p=0,034] and low performance status(OR=2.40 p=0.002) were significantly associated with psychological distress in patients with gastric cancer. Conclusions : These findings indicate that approximately half of patients with gastric cancer suffered from psychological distress and having alcohol drinking experience and low performance status would be associated risk factors, suggesting the need for distress screening and psychosocial supportive care in patients with gastric cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.763-767
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• 2014

Aim: To study the contribution of genetic variation in RAD51 to risk of esophageal squamous cell carcinoma (ESCC). Methods: Three single nucleotide polymorphisms (SNPs) in RAD51 (rs1801320, rs4144242 and rs4417527) were genotyped in 316 ESCC patients and 316 healthy controls in Anyang area of China using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism). Demographic variables between cases and controls were statistically compared by T test and Chi-square test. Hardy-Weinberg equilibrium was evaluated by the Chi-square test. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure any association with ESCC. Haplotype frequencies were estimated by Phase 2.1. Result: The genotype frequencies of rs1801320, rs4144242 and rs4417527 in patients with ESCC demonstrated no significant differences from those in control group (P>0.05). When the haplotypes of these three SNPs were constructed and their relationships with ESCC risk investigated, however, CGG was observed to increase the risk (P=0.020, OR=2.289). Conclusions: There was no association between the three SNPs of RAD51 and ESCC susceptibility in our Chinese population. However, the CGG haplotype might be a risk factor.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.81-87
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• 1995

Daily exposure of aflatoxin B1 (AFB1) was estimated in foods (rice, barley, soybean, peanut, soysauce, soybean paste) by ELISA (enzyme linked immunosorbent assay) using polyclonal antibody R101. Before ELISA, a simple extraction method was applied for the quantitation of AFB1 in foods using chloroform which showed high recovery (70$\pm$12%). AFB1 levels in foods were 0.32 ng/ml (rice), 0.24ng/ml (barley), 0.22 ng/ml (peanut), 0.30~0.78 ng/ml (soysauce), and 0.2 ng/ml (soybean paste). Based on food consumption, we estimated that Koreans were exposed to AFB1 at the level of 1.86$\pm$0.46 ng/kg/day and liver cancer incidence attributed to AFB1 exposure (assuming that AFB1 as a single hepatocarcinogenic agent) might be calculated to be 13.1 per 100, 000 population. Our data demonstrate that AFB1 levels in foods were below the regulation of 10 ppb in foods and might not be the major risk factor for the high incidence of lover cancer in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.7
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• pp.3035-3039
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• 2014

Background: Lung cancer is one of the most prevalent malignancies in the world and both incidence and mortality rates are continuing to rise in Pakistan. However, epidemiological studies to identify common lung cancer determinants in the Pakistani population have been limited. Materials and Methods: In this retrospective case-control study, 400 cases and 800 controls were enrolled from different hospitals of all provinces of Pakistan. Information about socio-demographic, occupational, lifestyle and dietary variables was extracted by questionnaire from all subjects. Odd ratios (ORs) and 95% confidence intervals (CIs) were calculated. and dose-response associations were also assessed for suitable factors. Results: Strong associations were observed for smoking (OR=9.4, 95%CI=6.9-12.8), pesticide exposure (OR=5.1, 95%CI=3.1-8.3), exposure to diesel exhaust (OR=3.1, 95%CI=2.1-4.5), red meat consumption (OR=2.9, 95%CI=1.8-4.7) and chicken consumption (OR=2.8, 95%CI=1.7-49). Other associated factors observed were welding fumes (OR=2.5, 95%CI=1.0-6.5), sedentary living (OR=2.0, 95%CI=1.6-2.6), family history (OR=2.0, 95%CI=0.8-4.9), wood dust (OR=1.9, 95%CI=1.2-3.1), tea consumption (OR=1.8, 95%CI=1.2-2.6), coffee consumption (OR=1.8, 95%CI=1.1-2.8), alcoholism (OR=1.7, 95%CI=1.1-2.5) and asbestos exposure(OR=1.5, 95%CI=0.5-4.4). Consumption of vegetables (OR=0.3, 95%CI=0.2-0.4), juices (OR=0.3, 95%CI=0.3-0.4), fruits (OR=0.7, 95%CI=0.5-0.9) and milk (OR=0.6, 95%CI=0.5-0.8) showed reduction in risk of lung cancer. Strongest dose-response relationships were observed for smoking ($X^2=333.8$, $p{\leq}0.0000001$), pesticide exposure ($X^2=50.9$, $p{\leq}0.0000001$) and exposure to diesel exhaust ($X^2=51.8$, $p{\leq}0.0000001$). Conclusions: Smoking, pesticide exposure, diesel exhaust and meat consumption are main lung cancer determinants in Pakistan. Consuming vegetables, fruits, milk and juices can reduce the risk of lung cancer risk, as in other countries.