• Communications for Statistical Applications and Methods
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• v.26 no.1
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• pp.1-9
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• 2019

Various probabilistic methods have been proposed for using interpopulation allele frequency differences to infer the ethnic group of a DNA specimen. The selection of the statistical method is critical because the accuracy of the statistical classification results vary. For the ancestry classification, we proposed a new ancestry evaluation method that estimate the combined ethnicity index as well as compared its performance with various classical classification methods using two real data sets. We selected 13 SNPs that are useful for the inference of ethnic origin. These single nucleotide polymorphisms (SNPs) were analyzed by restriction fragment mass polymorphism assay and followed by classification among ethnic groups. We genotyped 400 individuals from four ethnic groups (100 African-American, 100 Caucasian, 100 Korean, and 100 Mexican-American) for 13 SNPs and allele frequencies that differed among the four ethnic groups. Additionally, we applied our new method to HapMap SNP genotypes for 1,011 samples from 4 populations (African, European, East Asian, and Central-South Asian). Our proposed method yielded the highest accuracy among statistical classification methods. Our ethnic group classification system based on the analysis of ancestry informative SNP markers can provide a useful statistical tool to identify ethnic groups.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2605-2610
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• 2012

Background: Studies investigating the association of 2R/3R polymorphism in the thymidylate synthase 5'-untranslated enhanced region (TSER) and colorectal cancer (CRC) risk have reported conflicting results. Thus, a meta-analysis was performed to summarize the data on the potential association. Methods: Pubmed, Embase and CBM databases were searched for all available studies. Links between the TSER 2R/3R polymorphism and CRC risk were estimated by odds ratios (ORs) with 95% confidence intervals (CIs). Results: Seven case-control studies with a total of 2723 cases and 4030 controls were included in this meta-analysis. The results showed that the 3R variant of TSER 2R/3R polymorphism contributes to CRC risk in two comparison models (OR 3R vs. 2R =1.10, 95%CI 1.02-1.18, P = 0.015; OR Homozygote comparison model = 1.22 1.04-1.43, 95%CI 1.04-1.43, P = 0.012). Subgroup analyses by ethnicity further demonstrated a contribution in Caucasians with three comparison models (OR 3R vs. 2R = 1.10, 95%CI 1.02-1.19, P = 0.015; OR Homozygote comparison model = 1.21, 95%CI 1.03-1.41, P = 0.019; OR Recessive comparison model = 1.18, 95%CI 1.05-1.33, P = 0.008). However, the association in the Asian population was still uncertain due to the limited data (all P values were more than 0.05). Conclusions: Our meta-analysis suggests that the 3R variant of Thymidylate synthase 5'-untranslated enhanced region 2R/3R polymorphism contributes to gastric cancer risk in the Caucasian population, while any association in Asian populations needs further study.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.119-124
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• 2015

Background: DICER, one of the microRNA (miRNA) biogenesis proteins, is involved in the maturation of miRNAs and is implicated in cancer development and progression. The results from previous epidemiological studies on associations between DICER rs1057035 polymorphism and cancer risk were inconsistent. Thereforewe performed this meta-analysis to summarize possible associations. Materials and Methods: We searched all relevant articles on associations between DICER rs1057035 polymorphism and cancer risk from PubMed, EMBASE, Chinese Biomedical Literature and Chinese National Knowledge Infrastructure until August 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess any associations. Heterogeneity tests, sensitivity analyses and publication bias assessments were also performed in this meta-analysis. All analyses were conducted using STATA software. Results: Seven case-control studies, including 4,875 cancer cases and 7,800 controls were included in the meta-analysis. Overall, the results indicated that the C allele of DICER rs1057035 polymorphism was significantly associated with decreased cancer risk in allelic comparison, heterozygote and dominant genetic models (C vs T: OR=0.88, 95%CI 0.81-0.95, p=0.002; TC vs TT: OR=0.85, 95%CI 0.77-0.93, p=0.001; CC/TC vs TT: OR=0.86, 95%CI 0.78-0.94, p=0.001). In the subgroup analysis by ethnicity, a significantly decreased cancer risk was found in Asian but not Caucasian populations. Conclusions: The present meta-analysis suggests that the C allele of the DICER rs1057035 polymorphism probably decreases cancer risk. However, this association may be Asian-specific and the results should be treated with caution. Further well-designed studies based on larger sample sizes and group of populations are needed to validate these findings.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.1923-1927
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• 2012

Background: Studies investigating the association between 2R/3R polymorphisms in the thymidylate synthase 5'-untranslated enhanced region (TYMS 5'-UTR) and gastric cancer risk have generated conflicting results. Thus, a meta-analysis was performed to summarize the data on any association. Methods: Pubmed, Embase, and CNKI databases were searched for all available studies. The strength of association between TYMS 5'-UTR 2R/3R polymorphism and gastric cancer risk was estimated by odds ratios (ORs) with 95% confidence intervals (CIs). Results: Six individual case-control studies with a total of 1, 472 cases and 1, 895 controls were included into this meta-analysis. Analyses of total six relevant studies showed that there was no obvious association between the TYMS 5'-UTR 2R/3R polymorphism and gastric cancer risk. Subgroup analyses based on ethnicity showed 2R of TYMS 5'-UTR 2R/3R contributes to gastric cancer risk in the Asian population ($OR_{Homozygote\;model}$ = 1.71, 95%CI 1.19-2.46, P = 0.004; $OR_{Recessive\;genetic\;model}$ = 1.70, 95%CI 1.18-2.43, P = 0.004). However, the association in Caucasian populations was uncertain due to the limited studies. Conclusions: Our meta-analysis suggests that 2R of TYMS 5'-UTR 2R/3R contributes to gastric cancer risk in the Asian population, while this association in Caucasians populations needs further study.

• Journal of Korean Neurosurgical Society
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• v.66 no.5
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• pp.525-535
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• 2023

Objective : We performed an expanded multi-ethnic meta-analysis to identify associations between inflammation-related loci with intracranial aneurysm (IA) susceptibility. This meta-analysis possesses increased statistical power as it is based on the most data ever evaluated. Methods : We searched and reviewed relevant literature through electronic search engines up to August 2022. Overall estimates were calculated under the fixed- or random-effect models using pooled odds ratio (OR) and 95% confidence intervals (CIs). Subgroup analyses were performed according to ethnicity. Results : Our meta-analysis enrolled 15 studies and involved 3070 patients and 5528 controls including European, Asian, Hispanic, and mixed ethnic populations. Of 17 inflammation-related variants, the rs1800796 locus (interleukin [IL]-6) showed the most significant genome-wide association with IA in East-Asian populations, including 1276 IA patients and 1322 controls (OR, 0.65; 95% CI, 0.56-0.75; p=3.24#x00D7;10^-9) under a fixed-effect model. However, this association was not observed in the European population (OR, 1.09; 95% CI, 0.80-1.47; p=0.5929). Three other variants, rs16944 (IL-1β), rs2195940 (IL-12B), and rs1800629 (tumor necrosis factor-α) showed a statistically nominal association with IA in both the overall, as well as East-Asian populations (0.01<p<0.05). Conclusion : Our updated meta-analysis with increased statistical power highlights that rs1800796 which maps on the IL-6 gene is associated with IA, and in particular confers a protective effect against occurrence of IA in the East-Asian population.

• Toxicological Research
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• v.31 no.1
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• pp.25-32
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• 2015

The objectives of this study were to investigate the individual characteristics, lifestyle habits, exposure levels, and genetic diversity of xenobiotic-metabolizing enzymes involved in toluene metabolism in Korean and foreign workers exposed to toluene at a manufacturing plant. This study was conducted to determine the effects of culture or ethnicity on toluene metabolism. The results showed that blood and urinary toluene concentrations were dependent on the level of exposure to toluene. We analyzed the correlation between toluene metabolism and genetic diversity in glutathione S-transferase (GST) (M1), GSTT1, and cytochrome p-450 (CYP) $2E1^*5$ as well as lifestyle habits (smoking, drinking, and exercise habits). The results revealed significant correlations between toluene metabolism and GSTM1 and GSTT1 genetic diversity, as well as smoking and exercise.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4517-4520
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• 2012

Introduction: Northeastern Iran is known as a high risk area of upper gastrointestinal cancers. Recent reports have suggested a declining trend for these cancers as well as an increase in the incidence of other malignancies including breast cancer. Our present aim was to describe the epidemiological pattern of breast cancer in this region during 2004-2009. Methods: All new cancer cases from public and private diagnostic and therapeutic centers of Golestan province were registered. A structured questionnaire was prepared and used based on the standerds of the International Association of Cancer Registries. The international classification of diseases for oncology was considered for coding. Age standardized incidence rates (ASR) of breast cancer were calculated. Results: A total of 11,038 new cancer cases were registered during 2004-2009, of which, 1,101 (10%) were females with breast cancer. The median age of the breast cancer patients was 46 years. The ASR for breast cancer was 28 per 100,000 person-years. We found an unusual rapid increase in breast cancer rate at the age of 25 years. The ASR of breast cancer was significantly lower in females from Turkmen ethnicity and those from rural areas(P value <0.01). Conclusion: Our study showed high rate of breast cancer in Golestan province of Iran. We found an unusual peak of breast cancer in young women. So, the age of starting screening programs may need to be revised in this area. The rate of breast cancer was significantly lower in women from Turkmen ethnicity. Further studies are warranted to clarify the role of important determinants, especially regarding the ethnic disparity, on breast cancer in this region.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9347-9353
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• 2014

Background: Excision repair crossing-complementing group 2 (ERCC2), also called xeroderma pigmentosum complementary group D (XPD), plays a crucial role in the nucleotide excision repair (NER) pathway. Previous epidemiological studies have reported associations between ERCC2 polymorphisms and non-Hodgkin lymphoma (NHL) risk, but the results have remained controversial. Materials and Methods: We conducted this meta-analysis based on eligible case-control studies to investigate the role of two ERCC2 polymorphisms (Lys751Gln and Asp312Asn) in determining susceptibility to NHL. Ten case-control studies from several electronic databases were included in our study up to August 14, 2014. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed- or random-effects models to estimate the association strength. Results: The combined results based on all studies did not show any association between Lys751Gln/Asp312Asn polymorphisms and NHL risk for all genetic models. Stratified analyses by histological subtype and ethnicity did not indicate any significant association between Lys751Gln polymorphism and NHL risk. However, a significant reduced risk of NHL was found among population-based studies (Lys/Gln versus Lys/Lys: OR=0.87, 95% CI=0.77-0.99, P=0.037) but not hospital-based studies. As for Asp312Asn polymorphism, there was no evidence for the association between this polymorphism and the risk of NHL in all subgroup analyses. Conclusions: This meta-analysis suggests that there may be no association between Lys751Gln/Asp312Asn polymorphism and the risk of NHL and its two subtypes, whereas ERCC2 Lys751Gln heterozygote genotype may provide protective effects against the risk of NHL in population-based studies. Therefore, large-scale and well-designed studies are needed to clarify the effects of haplotypes, gene-gene, and gene-environment interactions on these polymorphisms and the risk of NHL and its different histological subtypes in an ethnicity specific population.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7533-7537
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• 2014

Background: Breast cancer (BC) is the most frequent cancer type, and the leading cause of death from cancer among women in Israel. The Bedouin-Arab (BA) population in southern Israel is characterized by a high rate of consanguinity, common hereditary disorders, and transition from a semi-nomadic, traditional society to a more sedentary and urbanized society. In this hospital-based study, the demographic and the clinicopathological characteristics of BC in BA were compared with Jewish patients. Materials and Methods: 85 BA patients treated at the Soroka Medical Center, Beer Sheba, during the years 2004-2012, were studied and compared with 180 consecutive Jewish patients treated during the year 2007. Clinicopathological features compared included age, menopausal state, number of births, a history of BC in first-degree relatives, tumor size (T), extent of lymph-node involvement (N), distant metastases (M), stage, grade, estrogen and progesterone receptor (ER/PR), and Her2 status. Types of treatment, relapse rate and site, as well as outcome were also studied. Cox's regression models were applied for studying disease-free, and overall survival. Results: Compared with Jewish patients, BA patients were younger (average age $49{\pm}12$ yrs vs $59{\pm}13$, p<0.001), had a lower rate of BC in first-degree relatives (p<0.001), and a larger number of births ($6{\pm}4.2$ vs $2.5{\pm}1.9$, p<0.001). BA patients had larger tumors (p=0.02), more extensive lymph-node involvement (p=0.002), and more advanced stage (p=0.003). Grade, ER, PR, and Her2 status were similar in the two ethnic groups. Relapse type was most commonly systemic in BA patients (p=0.05), and loco-regional in Jewish patients (p=0.02). Median survival was 63, and 35 months for Jewish and BA patients, respectively (log-rank test, p=0.02). In Cox multivariate analysis, stage and PR status (HR-0.14, p<0.0001; HR-3.11, p=0.046), but not ethnicity, influenced overall survival. Conclusions: BC presents a decade earlier, and with more advanced disease in BA compared with Jewish patients. Biologic parameters including grade, ER, PR, and Her2 status were similar in both groups. Although prognosis was worse in BA than in Jewish patients, it was affected only by stage and PR status, but not by ethnicity.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6381-6386
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• 2014

Background: The global burden of cancer is continuously increasing. According to recent report of the National Cancer Registry Programme (NCRP) on time trends it is estimated that future burden of cancer cases for India in 2020 will be 1,320,928. It is well known that knowledge of the incidence of cancer is a fundamental requirement of rational planning and monitoring of cancer control programs. It would help health planners to formulate public health policy if relevant ethnic groups were considered. North East-India alone contains over 160 Scheduled Tribes and 400 other sub-tribal communities and groups, whose cancer incidence rates are high compared to mainland India. As since no previous study was done focusing on ethnicity, the present investigation was performed. Materials and Methods: In this paper PBCR-Guwahati data on all cancer registrations from January 2009 to December 2011 for residents of the Kamrup Urban District, comprising an area of 261.8 sq. km with a total population of 900,518, including individual records with information on sex, age, ethnicity and cancer site are provided. Descriptive statistics including age adjusted rates (AARs) were taken as provided by NCRP. For comparison of proportional incidence ratios (PIR) the Student's t test was used, with p<0.05 considered as statistically significant. Results and Conclusions: Differences in leading sites of Kamrup Urban District since from the beginning of the PBCR-Guwahati were revealed among different ethnic groups by this study. The results should help policy makers to formulate different strategies to control the level of burden as well as for treatment planning. This study also suggests that age is an important factor of cancer among different ethnic populations as well as for overall population of Kamrup District of Assam.