Investigation of miRNA expression profiles using cohort samples reveals potential early detectability of colorectal cancers by serum miR-26a-5p before clinical diagnosis.

Previous studies have investigated the usefulness of microRNA (miRNA/miR) expression data for the early detection of colorectal cancer (CRC). However, limited data are available regarding miRNAs that detect CRC before clinical diagnoses. Accordingly, the present study investigated the early detectability of CRC by miRNAs using the preserved serum samples of the cohort participants affected with CRC within 2 years of study enrollment. First, the significant miRNAs were revealed using clinical CRC samples for a (seven early CRCs and seven controls) microarray analysis based on significance analysis of microarrays. Next, replicability was verified by reverse transcription-quantitative (RT-q)PCR (eight early CRCs and eight controls, together with 12 CRCs and 12 controls). Finally, early detectability was tested using the cohort samples of Japan Multi-Institutional Collaborative Cohort Study (17 CRCs and 17 controls) to reveal how a certain number of patients developed CRC within 2 years after participation. In the discovery phase, miRNA expression measurements were conducted using a 3D-Gene Human miRNA Oligo Chip for 2,555 miRNAs, and RT-qPCR analyses were performed to validate the replicability. In the first validation set with eight CRCs with early clinical stage and eight age- and gender-matched controls, miR-26a-5p and miR-223-3p demonstrated the highest diagnostic accuracy of area under the curve (AUC)=1.000 (sensitivity and specificity 100%). In an examination of the predictability of CRC incidence using pre-clinical cohort samples, miR-26a-5p demonstrated good predictability of advanced CRC incidence with an AUC of 0.840. Overall, the present study revealed serum miR-26a-5p as a potential early detection marker for CRC.

Associations between peroxisome proliferator-activated receptor γ (PPAR-γ) polymorphisms and serum lipids: Two cross-sectional studies of community-dwelling adults.

Dyslipidemia is a well-established risk factor for cardiovascular disease. Experimental studies have reported that peroxisome proliferator-activated receptor γ (PPAR-γ) regulates adipocyte differentiation, lipid storage, and glucose metabolism. Therefore, we examined the associations between PPAR-γ polymorphisms (rs1801282, rs3856806, rs12497191, rs1151999, and rs1152003) and serum lipids in two cross-sectional studies. In the Shizuoka area of the Japan Multi-Institutional Collaborative Cohort Study, we examined 4,952 participants (3,356 men and 1,596 women) in a baseline survey and 2,245 participants (1,550 men and 695 women) in a second survey 5 years later. Outcome measures were the prevalence of dyslipidemia (low-density lipoprotein-cholesterol [LDL-C] ≥ 140 mg/dl, high-density lipoprotein-cholesterol < 40 mg/dl, triglycerides ≥ 150 mg/dl, and/or use of cholesterol-lowering drugs) and the prevalence of high LDL-C (LDL-C ≥ 140 mg/dl and/or use of cholesterol-lowering drugs). Multivariate odds ratios (ORs) were estimated by using unconditional logistic regression models. A total of 2,114 and 1,431 individuals (42.7% and 28.9%) had dyslipidemia and high LDL-C in the baseline survey, respectively, as did 933 and 716 (41.6% and 31.9%), respectively, in the second survey. In the baseline study, compared with major allele homozygotes, minor allele homozygotes of rs3856806 and rs12497191 had a 42% (OR, 0.58; 95% confidence interval (CI), 0.39-0.85) and 23% (OR, 0.77; 95% CI, 0.60-0.99) lower risk of dyslipidemia, respectively, after adjustment for potential confounding factors. In addition, minor allele homozygotes of rs3856806 had a 45% (OR, 0.55; 95% CI, 0.35-0.86) lower risk of high LDL-C. Similar risk reductions were found in the second survey. In conclusion, rs3856806 and rs12497191 polymorphisms may be related to a lower risk of dyslipidemia and high LDL-C.

Associations between diet and mental health using the 12-item General Health Questionnaire: cross-sectional and prospective analyses from the Japan Multi-Institutional Collaborative Cohort Study.

BACKGROUND: Mental health has become a major public health issue worldwide. Biological and epidemiological studies suggest diet has a role in the prevention or cure of mental disorders. However, further research is required to elucidate the relationship between diet and mental health. This study aimed to investigate associations between dietary intake of nutrients (macronutrients, vitamins, calcium, and fatty acids) and food groups (fish, meat and chicken, dairy products, and vegetables) and mental health among middle-aged Japanese in cross-sectional and prospective studies. METHODS: In total, 9298 men and women that participated in two areas of the Japan Multi-Institutional Collaborative Cohort Study were eligible for analysis at the baseline (cross-sectional) survey. Of these, 4701 participants were followed for about 5 years and included in the follow-up (prospective) analysis. The 12-item General Health Questionnaire (GHQ) was used to assess participants' general mental health status over the past several weeks. The average intake of 46 foods over the past year was assessed by a validated food frequency questionnaire. We also evaluated lifestyle and medical factors using a self-administered questionnaire. A cross-sectional logistic regression analysis was performed to estimate odds ratios for a GHQ score ≥ 4 (poor mental health) according to dietary intake of foods/nutrients at baseline. The prospective study used baseline dietary and lifestyle factors and GHQ scores at follow-up. RESULTS: The cross-sectional logistic regression analysis showed vegetables, protein, calcium, vitamin D, carotene and n-3 highly-polyunsaturated fatty acids were inversely associated with a GHQ score ≥ 4. On the other hand, mono-unsaturated fatty acids showed a positive association with higher GHQ score. The prospective logistic regression analysis found dairy products, calcium, vitamin B2, and saturated fatty acids were inversely correlated with a GHQ score ≥ 4. Calcium was associated with GHQ scores in both the cross-sectional and follow-up studies. In the follow-up study, the multivariable-adjusted odds ratio for a GHQ score ≥ 4 was 0.71 (95% confidence interval, 0.55-0.92) for the highest versus lowest quartiles of calorie-adjusted dietary calcium intake. CONCLUSION: Consuming particular nutrients and foods, especially calcium and dairy products, may lead to better mental health in Japanese adults.

[EXAMINATION OF THE INCIDENCE AND RISK FACTORS ABOUT URINARY CANCERS (RENAL, BLADDER, AND PROSTATE) IN EXAMINEES OF HEALTH SCREENING].

(Objective) We studies morbidity and risk factors related to urinary cancers (renal, bladder, and prostate) from health screening interviews and results. (Subjects and Methods) We extracted data from 48,454 adults who underwent health screenings between April 2006 and March 2008.Of particular interest were examinees who were newly diagnosed with urinary cancer after the consultation. The data examined included factors such as sex, age, total years of smoking, body mass index (BMI), drinking status, weight gain (>10 kg from the age of 20), accumulation of stress, sleep condition/habits, adequate dairy product intake, hypertension, diabetes mellitus, and dyslipidemia. (Results) The numbers of patients who were diagnosed with renal, bladder, or prostatic cancer were 45, 47, and 215, respectively. The corresponding morbidity rates were 0.093%, 0.097%, and 0.721%. From the results of the univariate analysis, renal cancer was found to be significantly correlated with the male gender, old age, high BMI, drinking, weight gain, and hypertension. In addition, we found a significant correlation between bladder cancer and male gender, old age, total years of smoking, and drinking. Prostate cancer was significantly correlated with old age, total years of smoking, weight gain, accumulation of stress, and dyslipidemia. The multivariate analysis demonstrated a significant correlation between renal cancer and old age, between bladder cancer and both male gender and old age, and between prostatic cancer and both old age and dyslipidemia. (Conclusion) Old age was identified as a common risk factor that is significantly and independently correlated with urinary cancers.

A risk score predicting new incidence of hypertension in Japan.

The prevention of hypertension starts with the awareness of risk. Our aim was to construct a simple and well-validated risk model for nonhypertensive people in Japan consisting of basic clinical variables, using a dataset for two areas derived from the Japan Multi-Institutional Collaborative Cohort Study. We constructed a continuous-value model using data on 5105 subjects participating in both the baseline survey and a second survey conducted after 5 years. The area under the receiver operating characteristic curve (AUC) and the Hosmer-Lemeshow χ2 statistic for the entire cohort were 0.826 and 7.06, respectively. For validation, the entire cohort was randomly divided 100 times into derivation and validation sets at a ratio of 6:4. The summarized median AUC and the Hosmer-Lemeshow χ2 statistic were 0.83 and 12.2, respectively. The AUC of a point-based model consisting of integer scores assigned to each variable was 0.826 and showed no difference, compared with the continuous-value model. This simple risk model may help the general population to assess their risks of new-onset hypertension.

Common dysfunctional variants in ABCG2 are a major cause of early-onset gout.

Gout is a common disease which mostly occurs after middle age, but more people nowadays develop it before the age of thirty. We investigated whether common dysfunction of ABCG2, a high-capacity urate transporter which regulates serum uric acid levels, causes early-onset gout. 705 Japanese male gout cases with onset age data and 1,887 male controls were genotyped, and the ABCG2 functions which are estimated by its genotype combination were determined. The onset age was 6.5 years earlier with severe ABCG2 dysfunction than with normal ABCG2 function (P = 6.14 × 10(-3)). Patients with mild to severe ABCG2 dysfunction accounted for 88.2% of early-onset cases (twenties or younger). Severe ABCG2 dysfunction particularly increased the risk of early-onset gout (odds ratio 22.2, P = 4.66 × 10(-6)). Our finding that common dysfunction of ABCG2 is a major cause of early-onset gout will serve to improve earlier prevention and therapy for high-risk individuals.

DPP4 genetic variants influence baseline prostate-specific antigen levels: the J-MICC study.

Prostate specific antigen (PSA) testing plays a major role in prostate cancer screening; however, the low positive predictive value of PSA testing leads to many unnecessary biopsies. Genetic background is one of factors that could cause it. That's why an association between genetic background and PSA levels should be elucidated. This study aimed to investigate whether DPP4 genetic variants are associated with baseline PSA levels. A cross-sectional study was performed on 2,074 Japanese men aged between 35 and 69 in the Shizuoka area from the Japan Multi-institutional Collaborative Cohort (J-MICC) Study. Three DPP4 tagging single nucleotide polymorphisms (SNPs) were selected for genotyping: rs3788979 (A/G), rs7608798 (T/C), and rs2268889 (A/G). Higher mean serum PSA levels were significantly associated with an increase in the number of the rs7608798 C allele (p for trend = 0.02). A stratified analysis by age groups demonstrated that PSA levels had positive significant trends with the numbers of the minor alleles of rs3788979 or rs7608798 in the oldest group (men aged between 60 and 69) (p for trend=0.004 for rs3788979 and p for trend=0.001 for rs7608798). Haplotype analysis showed that the C-A (rs7608798-rs2268889) haplotype was significantly associated with increased PSA levels (p=0.006), compared with the most common haplotype, T-A. In summary, our study suggests that DPP4 genetic variants influence baseline PSA levels, especially in men aged between 60 and 69.

No association between MTHFR C677T and serum uric acid levels among Japanese with ABCG2 126QQ and SLC22A12 258WW.

Several genome-wide association studies (GWAS) have revealed that single nucleotide polymorphisms (SNPs) of ABCG2 and SLC22A12 were strongly associated with serum uric acid (SUA), but those of methylene tetrahydrofolate reductase (MTHFR) were not. However, there were several studies indicating the association with MTHFR C677T polymorphism. This study examined the association with the polymorphism, taking into account the genotypes of ABCG2 Q126X and SLC22A12 W258X. Subjects were 5,028 health checkup examinees of Seirei Preventive Health Care Center (3,416 males and 1,612 females) aged 35 to 69 years, who participated in the Japan Multi-Institutional Collaborative Cohort Study (J-MICC Study). Hyperuricemia was defined as SUA equal to 7 mg/dL or over. The genotype frequency was 35.9% for CC, 48.1% for CT, and 16.0% for TT, being in Hardy-Weinberg equilibrium (p=0.90). Among 4,425 participants with ABCG2 126QQ and SLC22A12 258WW who were not under medication for hyperuricemia, the mean SUA was 5.6 mg/dL, 5.6 mg/dL, and 5.7 mg/dL, respectively. When 114 participants with ABCG2 126QQ and SLC22A12 258WW under medication for hyperuricemia were included in hyperuricemia cases, the sex-age adjusted odds ratio (OR) of hyperuricemia was not significant; OR=1.00 (95% confidence interval, 0.89-1.24) for CT genotype and OR=0.98 (0.84-1.32) for TT genotype, relative to CC genotype. The present study indicated no association between SUA and MTHFR C677T genotype, after the influences of ABCG2 Q126X and SLC22A12 W258X were removed.

Association of obesity and diabetes with serum prostate-specific antigen levels in Japanese males.

Patients with diabetes have been reported to be at an increased risk for cancers of the pancreas, liver, and colon; however, recent studies have suggested that men with diabetes are at a decreased risk for prostate cancer. Previous studies have found that obese men have lower serum prostate-specific antigen (PSA) concentrations than do non-obese men. Further understanding of how obesity and diabetes affect the PSA concentration may improve our ability to detect clinically relevant prostate tumors. This study examined the relationships among serum PSA level, obesity, and diabetes in apparently healthy Japanese males. We analyzed the baseline data from 2,172 Japanese males (age, 56.8 +/- 6.1 years [mean +/- SD]) who participated in the Japan Multi-Institutional Collaborative Cohort Study. Diabetes was defined as the presence of both a hemoglobin A1c (JDS) of > or = 6.1% and a fasting plasma glucose level of > or = 126 mg/dL, or a positive medical history. After adjusting for age, the PSA levels were elevated among males with a higher normal BMI (ranging from 23.0 to 24.9) and lowered among men with a BMI of > or = 25.0. In the stratified analysis, these significant differences in BMI categories were absent among diabetics. The mean PSA levels were significantly lower in diabetics than in non-diabetics among subjects aged 60 and over. Our findings suggest that the pre-overweight men had increased PSA levels, and the diabetes was associated with a reduction of PSA levels in elderly.

Significant interaction between LRP2 rs2544390 in intron 1 and alcohol drinking for serum uric acid levels among a Japanese population.

A genome-wide association study identified that LRP2 rs2544390 in intron 1 was associated with serum uric acid (SUA) levels among Japanese, as well as polymorphisms of SLC22A12, ABCG2, and SLC2A9. This study aimed to confirm the association of rs2544390 C/T with SUA, as well as another LRP2 polymorphism (rs3755166 G/A) in the promoter. Subjects were 5016 health checkup examinees (3409 males and 1607 females) aged 35 to 69years with creatinine<2.0mg/dL. The subjects with SLC22A12 258WW, SLC2A9 rs11722228C allele, ABCG2 126QQ and 141Q allele (2546 males and 1199 females) were selected for analysis. Mean SUA was 6.03mg/dL for CC, 6.18mg/dL for CT, and 6.19mg/dL for TT among males (p=0.012), and 4.49mg/dL, 4.45mg/dL, and 4.42mg/dL among females (not significant), respectively. No association was observed for rs3755166. The association with rs2544390 was stronger among male drinkers. The odds ratio of drinking ≥5/week relative to no drinking for hyperuricemia (SUA≥7mg/dL and/or under medication for hyperuricemia) was 1.11 (95% confidence interval, 0.67-1.84) among CC males, 1.75 (1.22-2.51) among CT males, and 3.13 (1.80-5.43) among TT males. The interaction terms with drinking ≥5/week were 1.56 (p=0.156) for CT and 2.87 (p=0.005) for TT. This was the first report on the interaction between LRP2 genotype and alcohol drinking for SUA. Since the low density lipoprotein-related protein 2 (megalin) encoded by LRP2 is a multi-ligand endocytic receptor expressed in many tissues including the kidney proximal tubules, the association/interaction remained to be confirmed both epidemiologically and biologically.

Association between KLK3 rs2735839 G/A polymorphism and serum PSA levels in Japanese men.

OBJECTIVES: To clarify the association of kallikrein-related peptidase 3 (KLK3) rs2735839 G/A polymorphism with serum prostate-specific antigen (PSA) levels in Japanese men. METHODS: Subjects were participants of the Japan Multi-Institutional Collaborative Cohort (J-MICC) Study who visited the Seirei Preventive Health Care Center in Shizuoka, Japan. Among the 5,040 individuals aged 35-69 years who were enrolled in 2006-2007, serum PSA data were available for 2,323 male subjects without a past history of prostate cancer. The diagnostic criteria for PSA positivity was PSA ≥ 4.0 ng/ml. Genotyping of the KLK3 polymorphism was conducted by the polymerase chain reaction with the confronting two-pair primers (PCR-CTPP) method. RESULTS: The mean ± SD of PSA levels (mg/dl) were 1.54 ± 1.73 for those with KLK3 rs2735839 G/G genotype, 1.34 ± 1.33 for G/A, and 1.20 ± 1.23 for A/A, which was significantly different (p < 0.0001). The age-adjusted odds ratios of PSA test positivity were 0.62 (95% confidence interval 0.41-0.94) for those with G/A + A/A relative to those with G/G. CONCLUSIONS: The present study revealed that the KLK3 rs2735839 G allele was significantly associated with higher serum PSA levels also in Japanese.

Significant association of serum uric acid levels with SLC2A9 rs11722228 among a Japanese population.

Genome-wide association studies identified that SLC2A9 (GLUT9) gene polymorphisms were associated with serum uric acid (SUA) levels. Among the Japanese, a C/T polymorphism in intron 8 (rs11722228) was reported to be highly significant, though the function and strength of association were unknown. This study aimed to confirm the association, estimating the means of SUA according to the genotype, as well as OR of the genotype. Subjects were 5024 health checkup examinees (3413 males and 1611 females) aged 35 to 69 years with creatinine <2.0 mg/dL. Since SLC22A12 258X allele and ABCG2 126X allele are known to influence SUA levels strongly, the subjects with SLC22A12 258WW and ABCG2 126QQ (3082 males and 1453 females, in total 4535 subjects) were selected. The genotype frequency of SLC2A9 rs11722228 was 2184 for CC, 1947 for CT, and 404 for TT, being in Hardy-Weinberg equilibrium (p=0.312). Mean SUA was 6.10 mg/dL for CC, 6.25 mg/dL for CT, and 6.45 mg/dL for TT among males (p=1.5E-6), and 4.34 mg/dL, 4.59 mg/dL, and 4.87 mg/dL among females (p=4.6E-11), respectively. Males with SUA less than 5.0 mg/dL were 14.7% for CC, 10.6% for CT, and 7.8% for TT (p=2.3E-4), and females with SUA less than 4.0 mg/dL were 34.1%, 25.5%, and 15.4% (p=3.7E-6), respectively. This study was the first report to estimate the impact of SLC2A9 rs11722228 on SUA levels. Since the allele frequency of rs11722228 is similar among different ethnic groups, the impact remains to be examined in other ethnic groups.

No association between the frequency of forest walking and blood pressure levels or the prevalence of hypertension in a cross-sectional study of a Japanese population.

OBJECTIVE: To study the non-temporary effects of successive walks in forested areas (shinrin-yoku) on hypertension prevalence and blood pressure levels. METHODS: Data for the analysis were derived from the baseline survey of the Japan Multi-Institutional Collaborative Cohort (J-MICC) study in the Shizuoka area. Eligible participants were individuals aged 35-69 years who attended a health check-up center during 2006 and 2007. Of the 5,040 individuals who participated in the J-MICC study, Shizuoka, 4,666 were included in this analysis [3,174 men and 1,492 women; age (mean ± standard deviation) 52.1 ± 8.7 years]. The frequency of forest walking was estimated by a self-administrated questionnaire. Hypertension was defined as a systolic blood pressure ≥ 140 mmHg, a diastolic blood pressure ≥ 90 mmHg or, based on information provided in the questionnaire, the use of medication for hypertension. RESULTS: After adjusting for age, body mass index (BMI), smoking status, alcohol consumption, and habitual exercise, the odds ratios of hypertension associated with forest walking once a week or more frequently, relative to less than once a month were 0.98 in men [95% confidence interval (CI) 0.68-1.42] and 1.48 (95% CI 0.80-2.71) in women. There was no significant trend between adjusted blood pressure levels and the frequency of forest walking. CONCLUSION: The results of our cross-sectional study in a Japanese population show no association between either blood pressure levels or the prevalence of hypertension and the frequency of forest walking.

Clinicopathological features of gastric cancer detected by endoscopy as part of annual health checkup.

BACKGROUND AND AIM: Upper gastrointestinal endoscopy is generally accepted as the gold standard for the clinical evaluation of gastric cancer (GC). However, the efficacy of endoscopic screening for asymptomatic GC remains controversial. The present study is designed to clarify the efficacy of endoscopic screening for the detection of early GC by investigating the clinicopathological features. METHODS: A total of 17 522 patients who had underwent endoscopic screening as a part of their annual health checkup at the Seirei Center for Health Promotion and Preventive Medicine between April 2002 and March 2006 were enrolled in this study. We investigated the clinicopathological findings of GC detected by endoscopy. Furthermore, in accordance with the screening interval at our center, patients with GC were categorized into two groups: group A, patients with repeated endoscopic screening within the last 2 years, and group B, patients without endoscopic screening within the last 2 years. RESULTS: Thirty-nine GC (mean age of patients: 62.2 +/- 8.0 years, 36 males and three females) were detected in total (0.22%). The proportion of early GC was 87.2%. Notable differences between groups A and B were not found in the rate of early GC (P = 0.6342). However, eight of 27 cases (29.6%) in group A were treated by endoscopic resection, but none in group B (P = 0.0344). In six of 26 cases (23.1%) in group A, the recorded images from the previous endoscopic examination indicated some macroscopic abnormalities at the same location, suggesting GC or premalignant lesions. CONCLUSION: Endoscopic screening is useful for detecting GC at the early stages, and repeated examinations at short-time intervals contribute to the detection of resectable lesions by endoscopy. Further studies are needed to decrease the false negative rate of endoscopic screening.

Involvement of Helicobacter pylori infection and impaired glucose metabolism in the increase of brachial-ankle pulse wave velocity.

BACKGROUND: The role of Helicobacter pylori in the pathogenesis of atherosclerosis remains controversial. The present study was designed to elucidate the pathogenic role of H. pylori in the early stages of atherosclerosis by measurement of brachial-ankle pulse wave velocity (baPWV) in relation to glucose metabolism. MATERIALS AND METHODS: baPWV level, anti-H. pylori antibody, fasting blood glucose (FBG), and glycosylated hemoglobin A1c (HbA1c) and other conventional risk factors for cardiovascular diseases were measured in 947 subjects who attended their annual medical check-up. RESULTS: Multiple regression analyses indicated that age, gender (male), body mass index, FBG, systolic blood pressure, and smoking habits were each independently related to baPWV values. In younger subjects (30-49 years), H. pylori seropositivity was significantly correlated with an increase of baPWV levels (r = 0.100, p = .0445). baPWV values in the H. pylori-positive subjects with impaired glucose metabolism (IG: FBG >or= 110 mg/dL and/or HbA1c >or= 5.9%) were significantly greater than those in the H. pylori-negative subjects with IG (p = .0078). Furthermore, H. pylori-positive subjects with IG were at higher risk for increase of baPWV, in younger (r = 0.203, p < .0001) as well as in older subjects (50-69 years, r = 0.099, p = .0009). CONCLUSIONS: These results suggest that H. pylori seropositivity is a potential risk factor for increased baPWV levels, and that H. pylori infection accelerates the effect of IG on an increase of baPWV, especially in younger subjects. Thus, the possible interaction between H. pylori infection and IG may contribute to the early development of atherosclerosis.