Seaweed and Iodine Intakes and SLC5A5 rs77277498 in Relation to Thyroid Cancer

Background@#This study aims to elucidate the associations among dietary seaweed (gim and miyeok/dashima) and iodine intakes, the rs77277498 polymorphism of the SLC5A5 gene codifying the sodium/iodine symporter, and thyroid cancer risk in a Korean population. @*Methods@#We conducted a case-control study of 117 thyroid cancer cases and 173 controls who participated in the Cancer Screenee Cohort between 2002 and 2014 at the National Cancer Center, Korea. The amount of seaweed and iodine consumption (g/day) was estimated using the residual energy adjustment method. We calculated odds ratios (ORs) and their 95% confidence intervals (CIs) using a multivariable logistic regression model for the separate and combined effect of dietary iodine-based intake and SLC5A5 polymorphism (rs77277498, C>G) on thyroid cancer. @*Results@#Dietary gim and iodine intakes were inversely associated with thyroid cancer, with ORs of 0.50 (95% CI, 0.30 to 0.83) and 0.57 (95% CI, 0.35 to 0.95), respectively, whereas the associations for dietary miyeok/dashima and total seaweed intakes were not significant. However, compared with individuals carrying the C/C genotype of the rs77277498 polymorphism with a low intake of all dietary factors, those carrying the G allele with a high intake had a lower risk of thyroid cancer, with ORs of 0.25 (95% CI, 0.10 to 0.56), 0.31 (95% CI, 0.12 to 0.77), 0.26 (95% CI, 0.10 to 0.62), and 0.30 (95% CI, 0.12 to 0.73) for the consumption of gim, miyeok/dashima, total seaweed, and iodine, respectively. @*Conclusion@#In summary, our results supported the evidence of the protective effects of dietary gim and iodine intake against thyroid cancer risk, and this association can be strengthened by SLC5A5 rs77277498 genotypes.

Association among Body Mass Index, Genetic Variants of FTO, and Thyroid Cancer Risk: A Hospital-Based Case-Control Study of the Cancer Screenee Cohort in Korea / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Obesity has been determined to be associated with fat mass and obesity-associated (FTO) gene and thyroid cancer risk. However, the effect of combined interactions between obesity and the FTO gene on thyroid cancer needs further investigation. This study aimed to examine whether interactions between body mass index (BMI) and the FTO gene are associated with an increased risk of thyroid cancer. @*Materials and Methods@#A total of 705 thyroid cancer cases and 705 sex- and age-matched normal controls were selected from the Cancer Screenee Cohort in National Cancer Center, Korea. A conditional logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for the measure of associations and the combined effect of BMI and FTO gene on thyroid cancer. @*Results@#BMI was associated with an increased risk of thyroid cancer in subclasses of overweight (23-24.9 kg/m2; adjusted OR, 1.50; 95% CI, 1.12 to 2.00) and obese (≥ 25 kg/m2) (adjusted OR, 1.62; 95% CI, 1.23 to 2.14). There were positive associations between the FTO genetic variants rs8047395 and rs8044769 and an increased risk of thyroid cancer. Additionally, the combination of BMI subclasses and FTO gene variants was significantly associated with thyroid cancer risk in the codominant (rs17817288), dominant (rs9937053, rs12149832, rs1861867, and rs7195539), and recessive (rs17817288 and rs8044769) models. @*Conclusion@#Findings from this study identified the effects of BMI on thyroid cancer risk among individuals carrying rs17817288, rs9937053, rs12149832, rs1861867, rs7195539, and rs8044769, whereas the effects of BMI may be modified according to individual characteristics of other FTO variants.

Association among Body Mass Index, Genetic Variants of FTO, and Thyroid Cancer Risk: A Hospital-Based Case-Control Study of the Cancer Screenee Cohort in Korea / Journal of the Korean Cancer Association, 대한암학회지

Purpose@#Obesity has been determined to be associated with fat mass and obesity-associated (FTO) gene and thyroid cancer risk. However, the effect of combined interactions between obesity and the FTO gene on thyroid cancer needs further investigation. This study aimed to examine whether interactions between body mass index (BMI) and the FTO gene are associated with an increased risk of thyroid cancer. @*Materials and Methods@#A total of 705 thyroid cancer cases and 705 sex- and age-matched normal controls were selected from the Cancer Screenee Cohort in National Cancer Center, Korea. A conditional logistic regression model was used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for the measure of associations and the combined effect of BMI and FTO gene on thyroid cancer. @*Results@#BMI was associated with an increased risk of thyroid cancer in subclasses of overweight (23-24.9 kg/m2; adjusted OR, 1.50; 95% CI, 1.12 to 2.00) and obese (≥ 25 kg/m2) (adjusted OR, 1.62; 95% CI, 1.23 to 2.14). There were positive associations between the FTO genetic variants rs8047395 and rs8044769 and an increased risk of thyroid cancer. Additionally, the combination of BMI subclasses and FTO gene variants was significantly associated with thyroid cancer risk in the codominant (rs17817288), dominant (rs9937053, rs12149832, rs1861867, and rs7195539), and recessive (rs17817288 and rs8044769) models. @*Conclusion@#Findings from this study identified the effects of BMI on thyroid cancer risk among individuals carrying rs17817288, rs9937053, rs12149832, rs1861867, rs7195539, and rs8044769, whereas the effects of BMI may be modified according to individual characteristics of other FTO variants.

Genetic Risk Score, Combined Lifestyle Factors and Risk of Colorectal Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Both genetic and lifestyle factors contribute to the risk of colorectal cancer, but each individual factor has a limited effect. Therefore, we investigated the association between colorectal cancer and the combined effects of genetic factors or/and lifestyle risk factors. MATERIALS AND METHODS: In a case-control study of 632 colorectal cancer patients and 1,295 healthy controls, we quantified the genetic risk score for colorectal cancer using 13 polymorphisms. Furthermore, we determined a combined lifestyle risk score including obesity, physical activity, smoking, alcohol consumption, and dietary inflammatory index. The associations between colorectal cancer and risk score using these factors were examined using a logistic regression model. RESULTS: Higher genetic risk scores were associated with an increased risk of colorectal cancer (odds ratio [OR], 2.57; 95% confidence interval [CI], 1.89 to 3.49 for the highest tertile vs. lowest tertile). Among the modifiable factors, previous body mass index, physical inactivity, heavy alcohol consumption, and a high inflammatory diet were associated with an increased risk of colorectal cancer. A higher lifestyle risk score was associated with an increased risk of colorectal cancer (OR, 5.82; 95% CI, 4.02 to 8.44 for the highest tertile vs. lowest tertile). This association was similar in each genetic risk category. CONCLUSION: Adherence to a healthy lifestyle is associated with a substantially reduced risk of colorectal cancer regardless of individuals’ genetic risk.

Food Intake Behavior in Cancer Survivors in Comparison With Healthy General Population; From the Health Examination Center-based Cohort

BACKGROUND: This study aimed to investigate the food intake behavior of cancer survivors based on main sources of energy intake from different food groups in comparison with healthy individuals.METHODS: Baseline survey data from the Health Examinee cohort, which recruited participants from 2014 to 2013 were applied. A total of 5,269 cancer survivors and 5,219 healthy subjects without comorbidities who were matched by age, sex, and enrollment center were included in the analysis. The proportion of energy intake for 17 food groups was devided into lower median and median or upper. OR and 95% CIs were determined to measure the difference of energy intake proportion in cancer survivors, five major types of cancer survivors versus healthy individuals.RESULTS: Generally, the proportion of calories intake from sugars and sweets, meat and poultry, oils and fats, and beverage was lower in cancer survivors than in healthy individuals (OR = 0.83 [95% CI = 0.79–0.88], 0.75 [95% CI = 0.71–0.80], 0.84 [95% CI = 0.80–0.89], and 0.93 [95% CI = 0.88–0.99], respectively) with more prominently shown in breast, colon, and thyroid cancer individuals. In contrast, cancer survivors tended to intake calories from potatoes and starches, legume, seeds and nuts, vegetables, mushrooms, fruits, and seasonings more than healthy individuals (OR = 1.09 [95% CI = 1.03–1.16], 1.13 [95% CI = 1.06–1.19], 1.15 [95% CI = 1.09–1.22], 1.07 [95% CI = 1.01–1.13], 1.07 [95% CI = 1.02–1.14], 1.15 [95% CI = 1.08–1.21], and 1.17 [95% CI = 1.10–1.23], respectively) which were more prominent in gastric and breast cancer survivors.CONCLUSIONS: The dietary behavior measured by main sources of energy intake in cancer survivors was different from healthy individuals in terms of several food groups. Although there are nutrition guidelines for cancer survivors, because of the differences between Western population and Asian people in terms of food culture, the guidelines for balanced nutritious behavior should be established among Asian cancer survivors.

Genome-Wide Association of Genetic Variation in the PSCA Gene with Gastric Cancer Susceptibility in a Korean Population / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Half of the world's gastric cancer cases and the highest gastric cancer mortality rates are observed in Eastern Asia. Although several genome-wide association studies (GWASs) have revealed susceptibility genes associated with gastric cancer, no GWASs have been conducted in the Korean population, which has the highest incidence of gastric cancer. MATERIALS AND METHODS: We performed genome scanning of 450 gastric cancer cases and 1,134 controls via Affymetrix Axiom Exome 319 arrays, followed by replication of 803 gastric cancer cases and 3,693 healthy controls. RESULTS: We showed that the rs2976394 in the prostate stem cell antigen (PSCA) gene is a gastriccancer-susceptibility gene in a Korean population, with genome-wide significance and an odds ratio (OR) of 0.70 (95% confidence interval [CI], 0.64 to 0.77). A strong linkage disequilibrium with rs2294008 was also found, indicating an association with susceptibility. Individuals with the CC genotype of the PSCA gene showed an approximately 2-fold lower risk of gastric cancer compared to those with the TT genotype (OR, 0.47; 95% CI, 0.39 to 0.57). The effect of the PSCA gene on gastric cancer was more prominent in the female population and for diffuse type gastric cancer. CONCLUSION: Our result confirmed that the PSCA gene may be the most important susceptibility gene for gastric cancer risk in a Korean population.

Effects of Soy Product Intake and Interleukin Genetic Polymorphisms on Early Gastric Cancer Risk in Korea: A Case-Control Study / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The current study investigated whether the combined effects of soy intake and genetic polymorphisms of interleukin (IL) genes modify gastric cancer risk. MATERIALS AND METHODS: A total of 377 cases and 754 controls of Korean origin were included in the analysis. Soy consumption was assessed using a semi-quantitative food frequency questionnaire. Seven variants of IL10 (rs1800871), IL2 (rs2069763 and rs2069762), IL13 (rs6596090 and rs20541), and IL4R (rs7205663 and rs1805010) were genetically analyzed. To analyze the combined effect of soy intake and genetic polymorphisms, a low-intake group and high-intake group of each type of soy were categorized based on the intake level of the control group. Interactions between soy products and these genetic variants were analyzed by a likelihood ratio test, in which a multiplicative interaction term was added to the logistic regression model. RESULTS: A higher intake of nonfermented soy products was associated with a reduced cancer risk (odds ratio [OR], 0.62; 95% confidence interval [CI], 0.43 to 0.90), and the reduced risk was only apparent in males (OR, 0.44; 95% CI, 0.27 to 0.71). None of the IL genetic polymorphisms examined were independently associated with gastric cancer risk. Individuals with a minor allele of IL2 rs2069762 and a higher intake of nonfermented soy food had a decreased risk of gastric cancer (OR, 0.46; 95% CI, 0.31 to 0.68) compared to those with a lower intake (p(interaction)=0.039). CONCLUSION: Based on the genetic characteristics of the studied individuals, the interaction between IL2 rs2069762 and nonfermented soy intake may modify the risk of gastric cancer.

Risk Factors for Thyroid Cancer: A Hospital-Based Case-Control Study in Korean Adults / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Although the incidence of thyroid cancer in Korea has rapidly increased over the past decade, few studies have investigated its risk factors. This study examined the risk factors for thyroid cancer in Korean adults. MATERIALS AND METHODS: The study design was a hospital-based case-control study. Between August 2002 and December 2011, a total of 802 thyroid cancer cases out of 34,211 patients screened from the Cancer Screenee. Cohort of the National Cancer Center in South Korea were included in the analysis. A total of 802 control cases were selected from the same cohort, and matched individually (1:1) by age (±2 years) and area of residence for control group 1 and additionally by sex for control group 2. RESULTS: Multivariate conditional logistic regression analysis using the control group 1 showed that females and those with a family history of thyroid cancer had an increased risk of thyroid cancer, whereas ever-smokers and those with a higher monthly household income had a decreased risk of thyroid cancer. On the other hand, the analysis using control group 2 showed that a family history of cancer and alcohol consumption were associated with a decreased risk of thyroid cancer, whereas higher body mass index (BMI) and family history of thyroid cancer were associated with an increased risk of thyroid cancer. CONCLUSION: These findings suggest that females, those with a family history of thyroid cancer, those with a higher BMI, non-smokers, non-drinkers, and those with a lower monthly household income have an increased risk of developing thyroid cancer.

Diabetes Mellitus and Site-specific Colorectal Cancer Risk in Korea: A Case-control Study / 예방의학회지

OBJECTIVES: Previous large-scale cohort studies conducted in Korea have found a positive association between diabetes mellitus (DM) and colorectal cancer (CRC) in men only, in contrast to studies of other populations that have found significant associations in both men and women. METHODS: A total of 1070 CRC cases and 2775 controls were recruited from the National Cancer Center, Korea between August 2010 and June 2013. Self-reported DM history and the duration of DM were compared between cases and controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by binary and polytomous logistic regression models. RESULTS: DM was associated with an elevated risk of CRC in both men (OR, 1.47; 95% CI, 1.13 to 1.90) and women (OR, 1.92; 95% CI, 1.24 to 2.98). This association remained when we controlled for age, body mass index, alcohol consumption, and physical activity level. In sub-site analyses, DM was associated with distal colon cancer risk in both men (multivariate OR, 2.04; 95% CI, 1.39 to 3.00) and women (multivariate ORs, 1.99; 95% CI, 1.05 to 3.79), while DM was only associated with rectal cancer risk in women (multivariate OR, 2.05; 95% CI, 1.10 to 3.82). No significant association was found between DM and proximal colon cancer risk in either men (multivariate OR, 1.45; 95% CI, 0.88 to 2.41) or women (multivariate OR, 1.79; 95% CI, 0.78 to 4.08). CONCLUSIONS: Overall, DM was associated with an increased risk of CRC in Koreans. However, potential over-estimation of the ORs should be considered due to potential biases from the case-control design.

Association between nutrient intake and thyroid cancer risk in Korean women

BACKGROUND/OBJECTIVES: The incidence of thyroid cancer has increased in many countries, including Korea. International differences in the incidence of thyroid cancer may indicate a role of diet, but findings from previous studies are inconclusive. Therefore, we aimed to investigate the roles of nutrients in thyroid cancer risk in Korean women. SUBJECTS/METHODS: We conducted a case-control study comprising 113 cases and 226 age-matched controls. Nutrient intake was assessed using a validated food frequency questionnaire, and the association between nutrient intake and thyroid cancer risk was estimated using a logistic regression model. RESULTS: We found that high calcium intake was associated with a reduced risk of thyroid cancer (OR [95% CI] = 0.55 [0.35-0.89]). Significant associations were observed among subjects who were older than 50 years, had low BMI, and had low calorie intake. However, other nutrients included in this study did not show any significant associations with thyroid cancer risk. CONCLUSIONS: This study suggested a possible protective effect of calcium on thyroid cancer risk. Well-designed prospective studies are required to confirm these findings.

Association between nutrient intake and thyroid cancer risk in Korean women

BACKGROUND/OBJECTIVES: The incidence of thyroid cancer has increased in many countries, including Korea. International differences in the incidence of thyroid cancer may indicate a role of diet, but findings from previous studies are inconclusive. Therefore, we aimed to investigate the roles of nutrients in thyroid cancer risk in Korean women. SUBJECTS/METHODS: We conducted a case-control study comprising 113 cases and 226 age-matched controls. Nutrient intake was assessed using a validated food frequency questionnaire, and the association between nutrient intake and thyroid cancer risk was estimated using a logistic regression model. RESULTS: We found that high calcium intake was associated with a reduced risk of thyroid cancer (OR [95% CI] = 0.55 [0.35-0.89]). Significant associations were observed among subjects who were older than 50 years, had low BMI, and had low calorie intake. However, other nutrients included in this study did not show any significant associations with thyroid cancer risk. CONCLUSIONS: This study suggested a possible protective effect of calcium on thyroid cancer risk. Well-designed prospective studies are required to confirm these findings.