[Association of FokI rs2228570 and TMPRSS6 rs855791 polymorphisms with cow's milk protein allergy in children].

OBJECTIVE: To study the association of polymorphisms of FokI rs2228570 in the vitamin D receptor (VDR) gene and TMPRSS6 rs855791 with cow's milk protein allergy (CMPA) in children. METHODS: Quantitative real-time PCR was used to analyze the single nucleotide polymorphisms of FokI rs2228570 in the VDR gene and TMPRSS6 rs855791 in 100 children with CMPA and 100 healthy children (control group). The multivariate logistic regression model was used to identify the risk factors for CMPA. RESULTS: There were significant differences in the frequencies of CC, CT, and TT genotypes of TMPRSS6 rs855791 between the CMPA and control groups (P=0.008), and the CMPA group had a significantly higher frequency of TT genotype. The multivariate logistic regression analysis showed that the children with TT genotype of rs855791 had an increased risk of CMPA (OR=3.473, P=0.011). However, there was no significant difference in the genotype distribution of FokI rs2228570 in the VDR gene between the two groups (P=0.686). CONCLUSIONS: TMPRSS6 rs855791 polymorphism is associated with CMPA in children, and TT genotype may be the susceptible genotype of CMPA. FokI rs2228570 polymorphism is not associated with CMPA.

Association between polymorphisms within the susceptibility region 8q24 and breast cancer in a Chinese population.

Recent publications have found associations between single-nucleotide polymorphisms (SNPs) in 8q24 and the risk of breast cancer (BC) in some populations, but the conclusions are inconsistent. In order to further investigate the association between variants in this region and BC risk in Chinese population, we conducted an independent hospital-based case-control study to discern the effects of these SNPs on BC risk. We genotyped three 8q24 SNPs (rs13281615, rs6983267, and rs9642880) in 485 cases and 530 cancer-free controls. The results indicated that the rs13281615 G allele significantly increased BC risk, with an odds ratio (OR) of 1.23 (95% confidence interval (CI) = 1.03-1.46) under the allelic model. Besides, stratification analysis reported that the significant association remained in the estrogen receptor (ER)+/progesterone receptor (PR)+ subgroup with a P value of 0.007 under the allelic model (OR = 1.33, 95% CI = 1.08-1.63). For the rs9642880 variant, only a feeble association was observed for the GT genotype compared with the GG genotype (OR = 1.33, 95% CI = 1.01-1.74). In addition, there was a negligible association between rs6983267 and BC risk in the ER-/PR- subgroup. However, no significant finding was observed in the overall participants. The findings suggested that polymorphisms in 8q24 may contribute to susceptibility to BC risk. However, functional studies are warranted to further elucidate the mechanisms of the association.

Genetic variations in TERT-CLPTM1L locus are associated with risk of lung cancer in Chinese population.

Recent genome-wide association studies (GWAS) have reported multiple genetic variations at 5p15.33 (TERT-CLPTM1L) associated with risk of lung cancer. However, most of the associated variations identified by GWAS thus far are unlikely to be the actual causal variants, but may be mostly marker-single nucleotide polymorphisms tagging functional variations that influence gene expression. This study aimed to explore the function-validated and potentially functional variations in TERT-CLPTM1L locus conferring susceptibility to lung cancer. A case-control study including 502 cases and 502 controls in Chinese Han population was firstly conducted. Bioinformatic approaches are applied to prioritize genetic variations based on their potential functionality. In the logistic regression analysis, TERT-rs2853669, rs2736108, and CLPTM1L-rs31490 were significant associated with increased risk of lung cancer (OR = 1.46, 95% CI = 1.22-1.75; OR = 1.22, 95% CI = 1.00-1.49 and OR = 1.74, 95% CI = 1.35-2.23 under additive model, respectively). The significant associations were observed in non-small-cell lung cancer but not-in-small-cell lung cancer, and more prominent in adenocarcinoma. Haplotype analysis presented a significant allele-dose effect of haplotypes in increasing risk of lung cancer (P for trend = 1.894 × 10(-6)). Moreover, significant multiplicative interactions were observed between smoking and these three polymorphisms of TERT-rs2853669, rs2736108, and CLPTM1L-rs31490, even after bonferroni correction for multiple comparisons (Pinteraction = 1.316 × 10(-9), 3.912 × 10(-4), and 2.483 × 10(-5), respectively). These findings indicated that the function-validated and potentially functional variations in TERT-CLPTM1L locus, modified by smoking, may play a substantial role in the susceptibility to lung cancer.

The SLC4A7 variant rs4973768 is associated with breast cancer risk: evidence from a case-control study and a meta-analysis.

Recent genome-wide association study has identified a genetic variant rs4973768, located in 3'-UTR of solute carrier family 4, sodium bicarbonate cotransporter, member 7 (SLC4A7), was associated with increased risk of breast cancer (BC). However, several following replication studies cannot yield consistent results. We thus conducted a hospital-based case-control study including 485 patients and 514 controls, combined a meta-analysis including 108,632 cases and 135,818 controls to explore the relationship between this variant and BC risk. Our case-control study showed that rs4973768 was significantly associated with increased BC risk with the odds ratio (OR) of 1.29 (95 % confidence interval [CI]: 1.04-1.60) under the allelic model. In addition, the meta-analysis also indicated that the variant slightly increased the risk of BC with the pooled OR of the per-allele effect being 1.08 (95 % CI: 1.04-1.11) although with significant heterogeneity between studies. Stratified analyses showed that ethnicity, sample size, and study design may explain part of the heterogeneity. Moreover, the bioinformatics analysis suggested that this variant may influence the transcriptional capacity of SLC4A7. In summary, our results showed that the SLC4A7 variant, rs4973768, is associated with risk of BC although the underlying biologic mechanism warrants further studies.

A functional polymorphism, rs28493229, in ITPKC and risk of Kawasaki disease: an integrated meta-analysis.

Kawasaki disease (KD) is a multi-systemic vasculitis which preferentially affects infants and children. A single nucleotide polymorphism (rs28493229) in the inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) was identified to be associated with the increased risk of KD; however, in more recent studies associations have been controversial. Thus, we performed a meta-analysis, integrating case-control and transmission/disequilibrium test (TDT) studies, to investigate the relationship between this polymorphism and risk of KD. A total of ten case-control and two TDT studies, comprising 3,821 cases, 12,802 controls and 949 families, were included in this meta-analysis. There was a significant association between the C allele of rs28493229 and the increased risk of KD (OR = 1.53, 95 % CI = 1.34-1.74, P < 0.001), by the random-effects model because of heterogeneity (Q = 27.67, P (heterogeneity) = 0.004). Nevertheless, it was screened out by meta-regression analysis that the coronary artery lesions (CALs) status of KD could partly explain the heterogeneity, with consistently significant associations in both subgroups after stratification by CALs status. Moreover, estimates before and after the deletion of each study were similar in sensitivity analysis, indicating robust stability of the meta-analysis. This meta-analysis reveals that the functional polymorphism rs28493229 in ITPKC significantly contributes to the risk of KD.

Mortality attributable to carbapenem-resistant Pseudomonas aeruginosa bacteremia: a meta-analysis of cohort studies.

Whether carbapenem resistance is associated with mortality in patients with Pseudomonas aeruginosa bacteremia is controversial. To address this issue, we conducted a systematic review and meta-analysis based on cohort studies. We searched PubMed and Embase databases to identify articles (up to April 2015). The DerSimonian and Laird random-effect model was used to generate a summary estimate of effect. Associations were evaluated in subgroups based on different patient characteristics and study quality criteria. Seven studies with a total of 1613 patients were finally included, of which 1 study had a prospective design, and the other 6 were retrospective. Our meta-analysis showed patients with carbapenem-resistant P. aeruginosa bacteremia were at a higher risk of death compared with those with carbapenem-susceptible P. aeruginosa bloodstream infections (pooled odds ratio (OR) from three studies reporting adjusted ORs: 3.07, 95% confidence interval (CI), 1.60-5.89; pooled OR from 4 studies only reporting crude ORs: 1.46, 95% CI, 1.10-1.94). The results were robust across a number of stratified analyses and a sensitivity analysis. We also calculated that 8%-18.4% of deaths were attributable to carbapenem resistance in four studies assessing the outcome with 30-day mortality, and these were 3% and 14.6%, respectively, in two studies using 7-day mortality or mortality during bacteremia as an outcome of interest. Carbapenem resistance had a deleterious impact on the mortality of P. aeruginosa bacteremia; however, the results should be interpreted cautiously because only three studies reporting adjusted ORs were included. More large-scale, well-designed prospective cohorts, as well as mechanistic studies, are urgently needed in the future.

Identification of Iron Homeostasis Genes Dysregulation Potentially Involved in Retinopathy of Prematurity Pathogenicity by Microarray Analysis.

Retinopathy of prematurity (ROP) is a serious disease of preterm neonates and there are limited systematic studies of the molecular mechanisms underlying ROP. Therefore, here we performed global gene expression profiling in human fetal retinal microvascular endothelial cells (RMECs) under hypoxic conditions in vitro. Aborted fetuses were enrolled and primary RMECs were isolated from eyeballs. Cultivated cells were treated with CoCl2 to induce hypoxia. The dual-color microarray approach was adopted to compare gene expression profiling between treated RMECs and the paired untreated control. The one-class algorithm in significance analysis of microarray (SAM) software was used to screen the differentially expressed genes (DEGs) and quantitative RT-PCR (qRT-PCR) was conducted to validate the results. Gene Ontology was employed for functional enrichment analysis. There were 326 DEGs between the hypoxia-induced group and untreated group. Of these genes, 198 were upregulated in hypoxic RMECs, while the other 128 hits were downregulated. In particular, genes in the iron ion homeostasis pathway were highly enriched under hypoxic conditions. Our study indicates that dysregulation of genes involved in iron homeostasis mediating oxidative damage may be responsible for the mechanisms underlying ROP. The "oxygen plus iron" hypothesis may improve our understanding of ROP pathogenesis.

Systematic confirmation study of GWAS-identified genetic variants for Kawasaki disease in a Chinese population.

Genome-wide association studies (GWASs) have identified multiple single nucleotide polymorphisms (SNPs) associated with Kawasaki disease (KD). In this study, we replicated the associations of 10 GWAS-identified SNPs with KD in a Han Chinese population. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression, and cumulative effect of non-risk genotypes were also performed. Although none of the SNPs reached the corrected significance level, 4 SNPs showed nominal associations with KD risk. Compared with their respective wild type counterparts, rs1801274 AG+GG genotypes and rs3818298 TC+CC genotypes were nominally associated with the reduced risk of KD (OR = 0.77, 95% CI = 0.59-0.99, P = 0.045; OR = 0.74, 95% CI = 0.56-0.98, P = 0.038). Meanwhile, rs1801274 GG genotype, rs2736340 CC genotype or rs4813003 TT genotype showed a reduced risk trend (OR = 0.57, 95% CI = 0.35-0.93, P = 0.024; OR = 0.46, 95% CI = 0.26-0.83, P = 0.010; OR = 0.64, 95% CI = 0.43-0.94, P = 0.022), compared with rs1801274 AG+AA genotypes, rs2736340 CT+TT genotypes or rs4813003 TC+CC genotypes, respectively. Furthermore, a cumulative effect was observed with the ORs being gradually decreased with the increasing accumulative number of non-risk genotypes (Ptrend<0.001). In conclusion, our study suggests that 4 GWAS-identified SNPs, rs2736340, rs4813003, rs3818298 and rs1801274, were nominally associated with KD risk in a Han Chinese population individually and jointly.

The SNP rs931794 in 15q25.1 Is Associated with Lung Cancer Risk: A Hospital-Based Case-Control Study and Meta-Analysis.

BACKGROUND: Lung cancer is one of the most common human malignant diseases and the leading cause of cancer death worldwide. The rs931794, a SNP located in 15q25.1, has been suggested to be associated with lung cancer risk. Nevertheless, several genetic association studies yielded controversial results. METHODS AND FINDINGS: A hospital-based case-control study involving 611 cases and 1062 controls revealed the variant of rs931794 was related to increased lung cancer risk. Stratified analyses revealed the G allele was significantly associated with lung cancer risk among smokers. Following meta-analysis including 6616 cases and 7697 controls confirmed the relevance of rs931794 variant with increased lung cancer risk once again. Heterogeneity should be taken into account when interpreting the consequences. Stratified analysis found ethnicity, histological type and genotyping method were not the sources of between-study heterogeneity. Further sensitivity analysis revealed that the study "Hsiung et al (2010)" might be the major contributor to heterogeneity. Cumulative meta-analysis showed the trend was increasingly obvious with adding studies, confirming the significant association. CONCLUSIONS: Results from our current case-control study and meta-analysis offered insight of association between rs931794 and lung cancer risk, suggesting the variant of rs931794 might be related with increased lung cancer risk.

Non-linear dose-response relationship between cigarette smoking and pancreatic cancer risk: evidence from a meta-analysis of 42 observational studies.

BACKGROUND: Question remains about the shape of the dose-response relationship between cigarette smoking and pancreatic cancer risk. METHODS: Relevant studies were identified by searching PubMed, ISI Web of Science and China National Knowledge Infrastructure (CNKI) databases and by reviewing the reference lists of retrieved articles. Random-effects models were applied to estimate summary relative risks (RRs). RESULTS: Forty-two publications were finally included. The overall meta-analysis showed evidence of non-linear association between smoking intensity and pancreatic cancer risk (P for non-linearity=0.000). Compared with non-smokers, the summary RRs were 1.5 (95% confidence interval (CI): 1.4, 1.6) for 10 cigarettes/day, 1.9 (95% CI: 1.8, 2.0) for 20 cigarettes/day, 2.0 (95% CI: 1.9, 2.1) for 30 cigarettes/day and 2.1 (95% CI: 1.9, 2.3) for 40 cigarettes/day with marginal between-study heterogeneity (I(2)=29%). Similar results were also found for smoking duration and cumulative amount of cigarettes smoked. Besides, the summary RR for former smokers reduced with increasing time since quitting smoking compared with current smokers without heterogeneity (P for non-linearity=0.008, I(2)=0%). The results of stratified analysis by study design were comparable to those of overall meta-analysis. When stratified by sex, non-linear dose-response associations were detected for all metrics of cigarette smoking in women, while linear relationships were observed for smoking duration and cumulative amount of cigarettes smoked in men except for smoking intensity. CONCLUSION: This meta-analysis reveals a non-linear dose-response association between cigarette smoking and pancreatic cancer risk, but it might differ between sexes.

8p22-23-rs2254546 as a susceptibility locus for Kawasaki disease: a case-control study and a meta-analysis.

8p22-23-rs2254546 was firstly discovered to be associated with Kawasaki disease (KD) susceptibility by a genome-wide association study. However, only one Chinese replication study has been performed so far. To verify this association in another Chinese population, a hospital-based case-control study in Zhejiang province was conducted followed by an integrated meta-analysis, comprising five case-control studies of 1958 cases, 5615 controls and four transmission disequilibrium tests of 503 trios. In our case-control study, significant associations were observed between GG genotype or GG/GA genotypes of rs2254546 and increased KD risk (OR = 1.86, 95% CI = 1.01-3.41, P = 0.045; OR = 1.83, 95% CI = 1.01-3.33, P = 0.048), compared with AA genotype; however, no significant association was found in allelic model (OR = 1.20, 95% CI = 0.96-1.50, P = 0.117). The meta-analysis further revealed that the G allele was significantly associated with the increased KD risk without evidence of heterogeneity (OR = 1.55, 95% CI = 1.42-1.70, P < 0.001). In conclusion, rs2254546 polymorphism might significantly contribute to the risk of KD.

The roles of Ca2+/NFAT signaling genes in Kawasaki disease: single- and multiple-risk genetic variants.

Ca(2+)/nuclear factor of activated T-cells (Ca(2+)/NFAT) signaling pathway may play a crucial role in Kawasaki disease (KD). We investigated 16 genetic variants, selected by bioinformatics analyses or previous studies, in 7 key genes involved in this pathway in a Chinese population. We observed a significantly or marginally increased KD risk associated with rs2720378 GC + CC genotypes (OR = 1.39, 95% CI = 1.07-1.80, P = 0.014) or rs2069762 AC + CC genotypes (OR = 1.28, 95% CI = 0.98-1.67, P = 0.066), compared with their wild type counterparts. In classification and regression tree analysis, individuals carrying the combined genotypes of rs2720378 GC or CC genotype, rs2069762 CA or CC genotype and rs1561876 AA genotype exhibited the highest KD risk (OR = 2.12, 95% CI = 1.46-3.07, P < 0.001), compared with the lowest risk carriers of rs2720378 GG genotype. Moreover, a significant dose effect was observed among these three variants (Ptrend < 0.001). In conclusion, this study implicates that single- and multiple-risk genetic variants in this pathway might contribute to KD susceptibility. Further studies on more comprehensive single nucleotide polymorphisms, different ethnicities and larger sample sizes are warranted, and the exact biological mechanisms need to be further clarified.

Prevalence and associated risk factors of dyslexic children in a middle-sized city of China: a cross-sectional study.

BACKGROUND: There are many discussions about dyslexia based on studies conducted in western countries, and some risk factors to dyslexia, such as gender and home literacy environment, have been widely accepted based on these studies. However, to our knowledge, there are few studies focusing on the risk factors of dyslexia in China. Therefore, the aim of our study was to investigate the prevalence of dyslexia and its potential risk factors. METHODS: A cross-sectional study was conducted in Qianjiang, a city in Hubei province, China. Two stages sampling strategy was applied to randomly selected 5 districts and 9 primary schools in Qianjiang. In total, 6,350 students participated in this study and there were 5,063 valid student questionnaires obtained for the final analyses. Additional questionnaires (such as Dyslexia Checklist for Chinese Children and Pupil Rating Scale) were used to identify dyslexic children. The chi-square test and multivariate logistic regression were employed to reveal the potential risk factors to dyslexia. RESULTS: Our study revealed that the prevalence of dyslexia was 3.9% in Qianjiang city, which is a middle-sized city in China. Among dyslexic children, the gender ratio (boys to girls) was nearly 3∶1. According to the P-value in the multivariate logistic regression, the gender (P<0.01), mother's education level (P<0.01), and learning habits (P<0.01) (active learning, scheduled reading time) were associated with dyslexia. CONCLUSION: The prevalence rate of dyslexic children in middle-sized cities is 3.9%. The potential risk factors of dyslexic children revealed in this study will have a great impact on detecting and treating dyslexic children in China as early as possible, although more studies are still needed to further investigate the risk factors of dyslexic children in China.

Genetic variants in the folate pathway and the risk of neural tube defects: a meta-analysis of the published literature.

BACKGROUND: Neural Tube Defects (NTDs) are among the most prevalent and most severe congenital malformations worldwide. Polymorphisms in key genes involving the folate pathway have been reported to be associated with the risk of NTDs. However, the results from these published studies are conflicting. We surveyed the literature (1996-2011) and performed a comprehensive meta-analysis to provide empirical evidence on the association. METHODS AND FINDINGS: We investigated the effects of 5 genetic variants from 47 study populations, for a total of 85 case-control comparisons MTHFR C677T (42 studies; 4374 cases, 7232 controls), MTHFR A1298C (22 studies; 2602 cases, 4070 controls), MTR A2756G (9 studies; 843 cases, 1006 controls), MTRR A66G (8 studies; 703 cases, 1572 controls), and RFC-1 A80G (4 studies; 1107 cases, 1585 controls). We found a convincing evidence of dominant effects of MTHFR C677T (OR 1.23; 95%CI 1.07-1.42) and suggestive evidence of RFC-1 A80G (OR 1.55; 95%CI 1.24-1.92). However, we found no significant effects of MTHFR A1298C, MTR A2756G, MTRR A66G in risk of NTDs in dominant, recessive or in allelic models. CONCLUSIONS: Our meta-analysis strongly suggested a significant association of the variant MTHFR C677T and a suggestive association of RFC-1 A80G with increased risk of NTDs. However, other variants involved in folate pathway do not demonstrate any evidence for a significant marginal association on susceptibility to NTDs.

MNS16A tandem repeats minisatellite of human telomerase gene and cancer risk: a meta-analysis.

BACKGROUND: Researchers have provided evidence that telomere dysfunction play an important role in cancer development. MNS16A is a polymorphic tandem repeats minisatellite of human telomerase (hTERT) gene that influences promoter activity of hTERT and thus implicates to relate with risk of several malignancies. However, results on association between MNS16A and cancer risk remain controversial. We therefore conduct a meta-analysis to derive a more precise estimation of association between MNS16A and cancer risk. METHODS: A systematic literature search was conducted by searching PubMed, ISI Web of Knowledge, Human Genome and Epidemiology Network Navigator and Google Scholar digital database for publications on associations between MNS16A and cancer risk. Variants with statistically significant associations by meta-analysis were assessed using Venice criteria. RESULTS: 10 case-control articles enrolling 6101 cases and 10521 controls were brought into our meta-analysis. The relationships were strong epidemiological credibility in cerebral cancer and breast cancer population (P for heterogeneity > 0.1). The cumulative analysis in chronologic order suggested a clear tendency towards a significant association with additional study samples. CONCLUSIONS: The results provided a more accurate depiction of the role of MNS16A in cerebral cancer and breast cancer susceptibility. Additional larger studies were warranted to validate our findings.

Functional polymorphisms in FAS/FASL system increase the risk of neuroblastoma in Chinese population.

The FAS and FASL system plays a substantial role in apoptosis and immune escape of cells. Three polymorphisms located in the promoter regions of FAS (-1377G/A and -670A/G) and FASL (-844T/C) have been shown to alter the transcriptional activity of the genes, respectively. This study was conducted to evaluate the effects of these polymorphisms on the susceptibility of neuroblastoma in the Chinese population. A total of 203 patients with neuroblastoma and 411 controls were recruited in this case-control study. Polymerase chain reaction-based restriction fragment length polymorphism (PCR-RFLP) was applied for genotyping. Unconditional logistic regression was used to estimate cancer risk by calculating odds ratios (ORs) and their 95% confidence intervals (95% CIs). It was observed that significantly increased risks of neuroblastoma associated with FAS -1377G/A and FASL -844T/C polymorphisms, with ORs equal to 1.55 (95% CI, 1.10-2.20) for FAS -1377 A allele and 2.90 (95% CI, 2.04-4.12) for FASL -844CC genotype carriers compared with non-carriers, respectively. However, no association was found between the polymorphisms of FAS -670A/G and risk of neuroblastoma. In addition, the cumulative effect of FAS and FASL polymorphisms on risk of neuroblastoma was observed (P for trend = 2.502×10(-10)), with OR for the carriers of both FAS -1377A allele and FASL -844CC genotypes equaled to 3.95 (95% CI, 2.40-6.51). This work reveals that polymorphisms of FAS -1377G/A and FASL -844T/C but not FAS -670A/G are associated with risk of neuroblastoma in Chinese. These findings support the hypothesis that genetic polymorphism in FAS/FASL death system may influence individual susceptibility to neuroblastoma.

Exome sequencing identified NRG3 as a novel susceptible gene of Hirschsprung's disease in a Chinese population.

Hirschsprung's disease (HSCR) is a complex developmental defect characterized by the absence of enteric ganglia in the gastrointestinal tract. Although the genetic defect of enteric nervous system (ENS) was identified to play a critical role in the progress of HSCR, the systemic genetic dissection of HSCR still needs to be clarified. In this study, we firstly performed exome sequencing of two HSCR patients from a Han Chinese family, including the affected mother and son. After the initial quality filtering (coverage ≥ 5X and SNP quality score ≥ 40) of the raw data, we identified 13,948 and 13,856 single nucleotide variants (SNVs), respectively. We subsequently compared the SNVs against public databases (dbSNP130, HapMap, and 1000 Genome Project) and obtained a total of 15 novel nonsynonymous SNVs in 15 genes, which were shared between these two patients. Follow-up Sanger sequencing and bioinformatics analysis highlighted variant c.853G>A (p.E285K) in NRG3, a gene involved in the development of ENS. In the validation phase, we sequenced all nine exons of NRG3 in 96 additional sporadic HSCR cases and 110 healthy individuals and identified another nonsynonymous variant c.1329G>A (p.M443I) and two synonymous variants c.828G>A (p.T276T) and c.1365T>A (p.P455P) only in the cases. Our results indicated that NRG3 may be a susceptibility gene for HSCR in a Chinese population.

The genetic variant on chromosome 10p14 is associated with risk of colorectal cancer: results from a case-control study and a meta-analysis.

BACKGROUND: A common single nucleotide polymorphism (SNP), rs10795668, located at 10p14, was first identified to be significantly associated with risk of colorectal cancer (CRC) by a genome-wide association study (GWAS) in 2008; however, another GWAS and following replication studies yielded conflicting results. METHODS: We conducted a case-control study of 470 cases and 475 controls in a Chinese population and then performed a meta-analysis, integrating the current study and 9 publications to evaluate the association between rs10795668 and CRC risk. Heterogeneity among studies and publication bias were assessed by the χ²-based Q statistic test and Egger's test, respectively. RESULTS: In the case-control study, significant association between the SNP and CRC risk was observed, with per-A-allele OR of 0.71 (95%CI: 0.54-0.94, P = 0.017). The following meta-analysis further confirmed the significant association, with per-A-allele OR of 0.91 (95%CI: 0.89-0.93, P(heterogeneity) >0.05) in European population and 0.86 (95%CI: 0.78-0.96, P(heterogeneity) <0.05) in Asian population. Besides, sensitivity analyses and publication bias assessment indicated the robust stability and reliability of the results. CONCLUSIONS: Results from our case-control study and the followed meta-analysis confirmed the significant association of rs10795668 with CRC risk.

The SNP rs402710 in 5p15.33 is associated with lung cancer risk: a replication study in Chinese population and a meta-analysis.

BACKGROUND: Lung cancer is the most commonly diagnosed cancer and leading cause of cancer mortality in the world. A single nucleotide polymorphism (SNP), rs402710, located in 5p15.33, was firstly identified to be associated with the lung cancer risk in a genome-wide association study. However, some following replication studies yielded inconsistent results. METHODOLOGY AND FINDINGS: A case-control study of 611 cases and 1062 controls in a Chinese population was conducted, and then a meta-analysis integrating the current and previously published studies with a total 31811 cases and 36333 controls was performed to explore the real effect of rs402710 on lung cancer susceptibility. Significant associations between the SNP rs402710 and lung cancer risk were observed in both case-control study and meta-analysis, with ORs equal to 0.77 (95%CI = 0.63-0.95) and 0.83 (95%CI = 0.81-0.86) in dominant model, respectively. By stratified analysis of our case-control study, the associations were also observed in never smoker group and non-small cell lung cancer(NSCLC) group with ORs equal to 0.71 (95%CI = 0.53-0.95) and 0.69 (95%CI = 0.55-0.87), which was remarkable that larger effect of the minor allele T was seen in the two groups than that in overall lung cancer. Besides, the sensitive and cumulative analysis indicated the robust stability of the current results of meta-analysis. CONCLUSION: The results from our replication study and the meta-analysis provided firm evidence that rs402710 T allele significantly contributed to decreased lung cancer risk, and the case-control study implied that the variant may yield stronger effect on NSCLC and never smokers. However, the mechanism underlying the polymorphism conferring susceptibility to lung cancer is warranted to clarify in the follow-up studies.

Excess body mass index and risk of liver cancer: a nonlinear dose-response meta-analysis of prospective studies.

BACKGROUND: Excess body weight measured as body mass index (BMI) has a positive association with risk of common cancers. However, previous meta-analyses related to BMI and liver cancer had inconsistent results. The purpose of the current study is to establish a nonlinear dose-response relationship between BMI and incidence risk of liver cancer. METHODS: A systematic literature search for relevant articles published from 1966 to November 2011 was conducted in PUBMED and EMBASE digital databases. Additional articles were manually searched by using the reference lists of identified papers. Restricted cubic splines and generalized least-squares regression methods were used to model a potential curvilinear relationship and to make a dose-response meta-analysis. Stratified analysis, sensitivity analysis and assessment of bias were performed in our meta-analysis. RESULTS: 8 articles including 1,779,471 cohort individuals were brought into meta-analysis. A non-linear dose-response association between BMI and risk of liver cancer was visually significant (P for nonlinearity<0.001), besides, the point value of BMI also enhanced the results quantitatively, where relative risks were 1.02 (95%CI = 1.02-1.03), 1.35 (95%CI = 1.24-1.47) and 2.22-fold (95%CI = 1.74-2.83) when BMI was at the point of 25, 30 and 35 kg/m(2) compared with reference (the median value of the lowest category), respectively. The ethnicity of the population was found as the main source of heterogeneity. In subsequent stratified analysis, no evidence of heterogeneity was showed in Asian and White populations (P for heterogeneity>0.1), and all value of BMI still presented significantly increased risk of cancer. CONCLUSIONS: The findings from meta-analysis provided that excess BMI had significant increased association with risk of liver cancer, although the biological mechanisms underlying the obesity-cancer link still need to be clarified.