Higher Blood 25(OH)D Level May Reduce the Breast Cancer Risk: Evidence from a Chinese Population Based Case-Control Study and Meta-Analysis of the Observational Studies

Experimental data suggest a protective effect of vitamin D on breast cancer; however, epidemiologic results remain inclusive. With a Chinese population-based case-control study and meta-analysis of the observational studies, we here systematically evaluated the association of blood 25(OH)D level and breast cancer risk. With 593 breast cancer cases and 580 cancer-free controls from Shanghai, China, we found that 80% of the normal women had severe vitamin D deficiency (less than 20 ng/mL) and 15.2% had mild deficiency (20 to 30 ng/mL) and only 4.8% of women had sufficient vitamin D level (>30 ng/mL) while the proportion was 96.1%, 3.2% and 0.7% respectively for the breast cancer patients. Compared to those with the lowest quartile of plasma 25(OH)D level, women with highest quartile 25(OH)D level showed a significant decreased breast cancer risk (Q4 vs.Q1: OR = 0.10, 95% CI = 0.06–0.15) and every 1 ng/ml increment of plasma 25(OH)D level led to a 16% lower odds of breast cancer (OR = 0.84, 95% CI = 0.81–0.87; P<0.001). From the meta-analysis of the observational studies, we found that women with highest quantile of blood 25(OH)D level was associated with a significantly reduced breast cancer risk compared to those with lowest quantile of blood 25(OH)D level for the 11 nested case-control and retrospective studies (pooled OR = 0.86, 95% CI = 0.75–1.00) and 10 case-control studies (7 population based, OR = 0.35, 95% CI = 0.24–0.52; 3 hospital based, OR = 0.08, 95% CI = 0.02–0.33). These results suggest that vitamin D may have a chemo-preventive effect against breast cancer.     

Choline and Betaine Intake and Colorectal Cancer Risk in Chinese Population: A Case-Control Study

Background

Few studies have examined the association of choline and betaine intake with colorectal cancer risk, although they might play an important role in colorectal cancer development because of their role as methyl donors. The aim of this study was to examine the relationship between consumption of choline and betaine and colorectal cancer risk in a Chinese population.

Methodology/Principal Findings

A case-control study was conducted between July 2010 and December 2013 in Guangzhou, China. Eight hundred and ninety consecutively recruited colorectal cancer cases were frequency matched to 890 controls by age (5-year interval) and sex. Dietary information was assessed with a validated food frequency questionnaire by face-to-face interviews. The logistic regression model was used to estimate multivariate odds ratios (ORs) and 95% confidence intervals (CIs). Total choline intake was inversely associated with colorectal cancer risk after adjustment for various lifestyle and dietary factors. The multivariate-adjusted OR was 0.54 (95%CI = 0.37-0.80, Ptrend <0.01) comparing the highest with the lowest quartile. No significant associations were observed for betaine or total choline+betaine intakes. For choline-containing compounds, lower colorectal cancer risk was associated with higher intakes of choline from phosphatidylcholine, glycerophosphocholine and sphingomyelin but not for free choline and phosphocholine. The inverse association of total choline intake with colorectal cancer risk was observed in both men and women, colon and rectal cancer. These inverse associations were not modified by folate intake.

Conclusions

These results indicate that high intake of total choline is associated with a lower risk of colorectal cancer.     

Association between Chronic Obstructive Pulmonary Disease and Lung Cancer: A Case-Control Study in Southern Chinese and a Meta-Analysis

Background

Lung cancer and chronic obstructive pulmonary disease (COPD) share a common risk factor in cigarette smoking and a large portion of patients with lung cancer suffer from COPD synchronously. We therefore hypothesized that COPD is an independent risk factor for lung cancer. Our aim was to investigate the intrinsic linkage of COPD (or emphysema, chronic bronchitis and asthma) and lung cancer.

Methods

The present hospital-based case-control study included 1,069 patients with newly diagnosed lung cancer and 1,132 age frequency matched cancer-free controls. The odds ratios (ORs) for the associations between each previous pulmonary disease and lung cancer were estimated with logistic regression models, adjusting for age, sex, family history of cancer, BMI and pack year smoking. In meta-analysis, the pooled effects of previous pulmonary diseases were analyzed with random effects models; and stratification analyses were conducted on smoking status and ethnicity.

Results

In the case-control study, previous COPD was associated with the odds for increased risk of lung cancer (OR = 1.29, 95% confidence interval [CI] = 1.00∼1.68); so were emphysema (OR = 1.55, 95%CI = 1.03∼2.32) and chronic bronchitis (OR = 1.22, 95%CI = 0.99∼1.67); while asthma was associated with odds for decreased risk of lung cancer (OR = 0.29, 95%CI = 0.16∼0.53). These associations were more pronounced in smokers (P<.05 for all strata), but not in non-smokers. In meta-analysis, 35 studies (22,010 cases and 44,438 controls) were identified. COPD was significantly associated with the odds for increased risk of lung cancer (pooled OR = 2.76; 95% CI = 1.85–4.11), so were emphysema (OR = 3.02; 95% CI = 2.41–3.79) and chronic bronchitis (OR = 1.88; 95% CI = 1.49–2.36); and these associations were more pronounced in smokers than in non-smokers (P<.001 respectively). No significant association was observed for asthma.

Conclusion

Previous COPD could increase the risk of lung cancer, especially in smokers.     

Association between Diabetes and Risk of Aortic Dissection: A Case-Control Study in a Chinese Population

Background

It is well-recognized that diabetes represents a powerful independent risk factor for cardiovascular diseases. However, very few studies have investigated the relationship between diabetes and risk of aortic dissection (AD).

Aim

The aim of this case-control study was to evaluate the association between diabetes and risk of AD in Chinese population.

Methods

A hospital-based case-control study, consisting of 2160 AD patients and 4320 controls, was conducted in a Chinese population. Demographic, clinical characteristics and risk factors were collected. Diabetes rate of patients with overall AD, Stanford type A AD and type B AD group was compared with that of corresponding matched control groups. Logistic regression analysis was used to estimate the odds ratios (OR) and 95% confidence intervals (95% CI) for relationship between diabetes and AD risk.

Results

The prevalence of diabetes was lower in AD cases than that of control subjects, whether it is the overall AD, type A AD or type B AD group (4.7% vs. 10.0%, 2.9% vs. 8.8%, 5.9% vs. 10.9%, all P<0.001). Furthermore, in multivariate model, diabetes was found to be associated with lower AD risk, which not only applies to the overall AD (OR = 0.2, 95%CI: 0.15–0.26), but also type A AD (OR = 0.12, 95% CI: 0.07–0.20) and type B AD (OR = 0.25, 95%CI: 0.18–0.33).

Conclusions

We observed the paradoxical inverse relationship between DM and risk of AD in the Chinese population. These results suggest diabetes may play a protective role in the development of AD. However, further studies are needed to enrich related evidence, especially with regard to underlying mechanisms for these trends.     

Pathway Analysis for Genome-Wide Association Study of Lung Cancer in Han Chinese Population

Genome-wide association studies (GWAS) have identified a number of genetic variants associated with lung cancer risk. However, these loci explain only a small fraction of lung cancer hereditability and other variants with weak effect may be lost in the GWAS approach due to the stringent significance level after multiple comparison correction. In this study, in order to identify important pathways involving the lung carcinogenesis, we performed a two-stage pathway analysis in GWAS of lung cancer in Han Chinese using gene set enrichment analysis (GSEA) method. Predefined pathways by BioCarta and KEGG databases were systematically evaluated on Nanjing study (Discovery stage: 1,473 cases and 1,962 controls) and the suggestive pathways were further to be validated in Beijing study (Replication stage: 858 cases and 1,115 controls). We found that four pathways (achPathway, metPathway, At1rPathway and rac1Pathway) were consistently significant in both studies and the P values for combined dataset were 0.012, 0.010, 0.022 and 0.005 respectively. These results were stable after sensitivity analysis based on gene definition and gene overlaps between pathways. These findings may provide new insights into the etiology of lung cancer.     

Previous Exposure to Statin May Reduce the Risk of Subsequent Non-Hodgkin Lymphoma: A Nationwide Population-Based Case-Control Study

Background

The purpose of this study was to investigate the association between previous exposure to statins and the risk of non-Hodgkin lymphoma (NHL).

Methods

This nationwide population-based case–control study was conducted using the National Health Insurance Research Database of Taiwan. The NHL group consisted of the patients with a first-time diagnosis of NHL between 2005 and 2008. The cases of the control group were pair-matched to the NHL group according to sex, year of birth and date of NHL diagnosis (index date). The statin administration data from both groups were retrospectively collected from the index date to January 1, 1996. The cumulative defined daily dose (cDDD) was estimated to evaluate the statin exposure. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariate logistic regression.

Results

The study population was composed of 1715 NHL patients and 16942 control subjects. The analysis revealed that previous statin administration was associated with a reduced risk of subsequent NHL with an adjusted OR of 0.52 (95% CI, 0.43–0.62). Additionally, there was a dose-response relationship between statin administration and the risk of NHL. The adjusted ORs were 0.63 (95% CI, 0.46–0.86), 0.58 (95% CI, 0.42–0.79), 0.51 (95% CI, 0.38–0.67), and 0.36 (95% CI, 0.24–0.53) for the subjects with statin administrations of fewer than 28, 28 to 90, 91 to 365, and more than 365 cDDDs, respectively, relative to the subjects without any statin administration.

Conclusions

The results of this study suggest that previous statin administration is associated with a lower risk of subsequent NHL. As statins are widely used medications, the magnitude of the risk reduction may have a substantial influence on public health. Further studies to confirm our findings are warranted.     

UGT1A6 Polymorphisms Modulated Lung Cancer Risk in a Chinese Population

Uridine diphosphoglucuronosyltransferases (UGTs) 1A6 is the only UGT1A isoform expressed in lung tissue. It is responsible for the detoxification of carcinogens such as benezo[a]pyrene from cigarette smoke. The purpose of this study was to evaluate the association of UGT1A6 polymorphisms and haplotypes with lung cancer risk and to evaluate the functional significance of UGT1A6 polymorphisms. Genomic DNA was isolated from leukocytes. Eight UGT1A6 polymorphisms were sequenced in a test set of 72 Chinese lung cancer patients and 62 healthy controls. Potential risk modifying alleles were validated in a separate set of 95 Chinese lung cancer patients and 100 healthy controls. UGT1A6 19T>G, 541A>G and 552A>C showed significant association with increased lung cancer risk, while UGT1A6 105C>T and IVS1+130G>T were significantly associated with reduced lung cancer risk. Multivariate logistic regression analysis demonstrated a significant association of lung cancer with UGT1A6 541A>G (OR: 3.582, 95% CI: 1.27–10.04, p = 0.015), 552A>C (OR: 5.364, 95% CI: 1.92–14.96, p = 0.001) and IVS1+130G>T (OR: 0.191, 95% CI: 0.09–0.36, p<0.001). Functional test demonstrated that UGT1A6 105C>T increased mRNA stability, providing a plausible explanation of its association with reduced lung cancer risk. Thus UGT1A6 polymorphisms may be used to identify people with increased risk of developing lung cancer.     

Effect of Single Nucleotide Polymorphism Rs189037 in ATM Gene on Risk of Lung Cancer in Chinese: A Case-Control Study

Background

Accumulated evidence has indicated that ataxia-telangiectasia mutated (ATM) gene polymorphisms are closely related to lung cancer. We aimed to explore the prognostic value of rs189037 (G>A), one of ATM single nucleotide polymorphisms (SNPs), and detect whether it involves in the risk of lung cancer in Chinese Han people.

Methods

In this hospital-based matched case-control study, 852 lung cancer patients and 852 healthy controls have been put into comparison to analyze the association between rs189037 and lung cancer risk in Chinese. The single nucleotide polymorphisms were determined by TaqMan real-time PCR and we used SPSS software to perform the statistical analyses.

Results

Individuals carrying variant AA genotype of rs189037 had higher lung cancer risk (adjusted OR: 1.56) than those carrying GG genotype. After analyzing data respectively from different groups divided by genders and smoking status, we observed that the risk effect of AA genotype on the lung cancer was significant in females, non-smokers and female non-smokers, as well as the risk effect of GA genotype in male smokers. Compared with non-smokers carrying GG genotype, smokers carrying at least one A allele had higher risk of developing lung cancer than those with GG genotype (adjusted OR: 3.52 vs. adjusted OR: 2.53).

Conclusions

This study suggested that rs189037 (G>A) polymorphism is associated with lung cancer risk in Chinese Han population. AA genotype and A allele may be dangerous lung cancer signals in Chinese and make contribution to diagnostic and treatment value.     

Genetic Variations in Key MicroRNA Processing Genes and Risk of Head and Neck Cancer: A Case-Control Study in Chinese Population

MicroRNAs (miRNAs) have been reported to play a key role in oncogenesis. Genetic variations in miRNA processing genes and miRNA binding sites may affect the biogenesis of miRNA and the miRNA-mRNA interactions, hence promoting tumorigenesis. In the present study, we hypothesized that potentially functional polymorphisms in miRNA processing genes may contribute to head and neck cancer (HNC) susceptibility. To test this hypothesis, we genotyped three SNPs at miRNA binding sites of miRNA processing genes (rs1057035 in 3′UTR of DICER, rs3803012 in 3′UTR of RAN and rs10773771 in 3′UTR of HIWI) with a case-control study including 397 HNC cases and 900 controls matched by age and sex in Chinese. Although none of three SNPs was significantly associated with overall risk of HNC, rs1057035 in 3′UTR of DICER was associated with a significantly decreased risk of oral cancer (TC/CC vs. TT: adjusted OR  = 0.65, 95% CI  = 0.46–0.92). Furthermore, luciferase activity assay showed that rs1057035 variant C allele led to significantly lower expression levels as compared to the T allele, which may be due to the relatively high inhibition of hsa-miR-574-3p on DICER mRNA. These findings indicated that rs1057035 located at 3′UTR of DICER may contribute to the risk of oral cancer by affecting the binding of miRNAs to DICER. Large-scale and well-designed studies are warranted to validate our findings.     

Chronic Obstructive Pulmonary Disease and Altered Risk of Lung Cancer in a Population-Based Case-Control Study

Background

Chronic obstructive pulmonary disease (COPD) has been consistently associated with increased risk of lung cancer. However, previous studies have had limited ability to determine whether the association is due to smoking.

Methodology/Principal Findings

The Environment And Genetics in Lung cancer Etiology (EAGLE) population-based case-control study recruited 2100 cases and 2120 controls, of whom 1934 cases and 2108 controls reported about diagnosis of chronic bronchitis, emphysema, COPD (chronic bronchitis and/or emphysema), or asthma more than 1 year before enrollment. We estimated odds ratios (OR) and 95% confidence intervals (CI) using logistic regression. After adjustment for smoking, other previous lung diseases, and study design variables, lung cancer risk was elevated among individuals with a history of chronic bronchitis (OR = 2.0, 95% CI = 1.5–2.5), emphysema (OR = 1.9, 95% CI = 1.4–2.8), or COPD (OR = 2.5, 95% CI = 2.0–3.1). Among current smokers, association between chronic bronchitis and lung cancer was strongest among lighter smokers. Asthma was associated with a decreased risk of lung cancer in males (OR = 0.48, 95% CI = 0.30–0.78).

Conclusions/Significance

These results suggest that the associations of personal history of chronic bronchitis, emphysema, and COPD with increased risk of lung cancer are not entirely due to smoking. Inflammatory processes may both contribute to COPD and be important for lung carcinogenesis.     

Shared Air: A Renewed Focus on Ventilation for the Prevention of Tuberculosis Transmission

Background

Despite an improvement in the overall TB cure rate from 40–74% between 1995 and 2011, TB incidence in South Africa continues to increase. The epidemic is notably disquieting in schools because the vulnerable population is compelled to be present. Older learners (age 15–19) are at particular risk given a smear-positive rate of 427 per 100,000 per year and the significant amount of time they spend indoors. High schools are therefore important locations for potential TB infection and thus prevention efforts.

Methods and Findings

Using portable carbon dioxide monitors, we measured CO₂ in classrooms under non-steady state conditions. The threshold for tuberculosis transmission was estimated using a carbon dioxide-based risk equation. We determined a critical rebreathed fraction of carbon dioxide () of 1·6%, which correlates with an indoor CO₂ concentration of 1000 ppm. These values correspond with a ventilation rate of 8·6 l/s per person or 12 air exchanges per hour (ACH) for standard classrooms of 180 m³.

Conclusions

Given the high smear positive rate of high-school adolescents in South Africa, the proposal to achieve CO₂ levels of 1000ppm through natural ventilation (in the amount 12 ACH) will not only help achieve WHO guidelines for providing children with healthy indoor environments, it will also provide a low-cost intervention for helping control the TB epidemic in areas of high prevalence.     

Genetic Variants in Nitric Oxide Synthase Genes and the Risk of Male Infertility in a Chinese Population: A Case-Control Study

Background

In recent years, oxidative stress has been studied extensively as a main contributing factor to male infertility. Nitric Oxide, a highly reactive free radical gas, is potentially detrimental to sperm function and sperm DNA integrity at high levels. Thus, the aim of this study was to investigate the associations between five polymorphisms in nitric oxide synthase genes (NOSs) and the risk of male infertility and sperm DNA damage as well.

Methods

Genotypes were determined by the OpenArray platform. Sperm DNA fragmentation was detected using the Tdt-mediated dUTP nick-end labeling assay, and the level of 8-hydroxydeoxyguanosine (8-OHdG) in sperm DNA was measured using immunofluorescence. The adjusted odds ratio (OR) and 95% confidence interval (CI) were estimated using unconditional logistic regression.

Results

Our results revealed a statistically significant difference between the cases and controls in both genotypic distribution (P<0.001) and allelic frequency (P = 0.021) only for the NOS3 rs1799983 SNP. Multivariate logistic regression analyses revealed that rs1799983 was associated with a borderline significantly increased risk of male infertility (GT vs. GG: adjusted OR = 1.30, 95% CI: 1.00–1.70; GT+TT vs. GG: adjusted OR = 1.34, 95% CI: 1.03–1.74; P _trend = 0.020). Moreover, NOS3 rs1799983 was positively associated with higher levels of sperm DNA fragmentation (β = 0.223, P = 0.044). However, the other 4 polymorphisms (NOS1 rs2682826, NOS1 rs1047735, NOS2 rs2297518, and NOS2 rs10459953) were not found to have any apparent relationships with male infertility risk.

Conclusions

Of five NOS gene polymorphisms investigated in the present study, we found NOS3 rs1799983 might cause oxidative sperm DNA damage, thereby contributing to male infertility.     

The Joint Effects of Lifestyle Factors and Comorbidities on the Risk of Colorectal Cancer: A Large Chinese Retrospective Case-Control Study

Background

Colorectal cancer (CRC) is a major cause of cancer morbidity and mortality. In previous epidemiologic studies, the respective correlation between lifestyle factors and comorbidity and CRC has been extensively studied. However, little is known about their joint effects on CRC.

Methods

We conducted a retrospective case-control study of 1,144 diagnosed CRC patients and 60,549 community controls. A structured questionnaire was administered to the participants about their socio-demographic factors, anthropometric measures, comorbidity history and lifestyle factors. Logistic regression model was used to calculate the odds ratio (ORs) and 95% confidence intervals (95%CIs) for each factor. According to the results from logistic regression model, we further developed healthy lifestyle index (HLI) and comorbidity history index (CHI) to investigate their independent and joint effects on CRC risk.

Results

Four lifestyle factors (including physical activities, sleep, red meat and vegetable consumption) and four types of comorbidity (including diabetes, hyperlipidemia, history of inflammatory bowel disease and polyps) were found to be independently associated with the risk of CRC in multivariant logistic regression model. Intriguingly, their combined pattern- HLI and CHI demonstrated significant correlation with CRC risk independently (OR_HLI: 3.91, 95%CI: 3.13–4.88; OR_CHI: 2.49, 95%CI: 2.11–2.93) and jointly (OR: 10.33, 95%CI: 6.59–16.18).

Conclusions

There are synergistic effects of lifestyle factors and comorbidity on the risk of colorectal cancer in the Chinese population.     

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.     

Association of Genetic Variants in the Adiponectin Gene with Metabolic Syndrome: A Case-Control Study and a Systematic Meta-Analysis in the Chinese Population

Background

The prevalence of metabolic syndrome has been rising worldwide, including in China, but knowledge on specific genetic determinants of metabolic syndrome is very limited. A number of studies have reported that polymorphisms in the ADIPOQ gene are associated with metabolic syndrome in Chinese Han populations. However, data is still conflicting. The objective of this study was to examine the associations of the adiponectin genetic variants with metabolic syndrome by a case-control study and meta-analyses in Chinese.

Methods

We first investigated the association of ADIPOQ rs2241766 (+45T>G in exon 2), rs266729 (−11377C>G in promoter) and rs1501299 (+276G>T in intron 2) polymorphisms with metabolic syndrome in a Hubei Han Chinese population with 322 metabolic syndrome patients and 161 normal controls recruited from the Yichang, Hubei. Then we comprehensively reviewed the association between ADIPOQ rs2241766/rs266729/rs1501299 and metabolic syndrome in the Chinese populations via a meta-analysis. The strength of association was assessed by odds ratios (ORs) with 95% confidence intervals (CI).

Results

The G allele frequency of rs2241766 in metabolic syndrome patients was significantly higher than those of controls group (29.8% vs 23.3%, OR = 1.40, P = 0.033). The logistic regression analysis adjusted by gender and age showed a nominally significant association for rs2241766 GG+GT genotype (P = 0.065, OR = 1.55) and rs1501299 GG genotype in recessive model (OR = 1.54, P = 0.066). However, no association was observed for rs266729 in our sample. We identified thirteen studies for rs2241766 (2,684 metabolic syndrome patients and 2,864 controls), three studies for rs266729, and eleven studies for rs1501299 (2,889 metabolic syndrome patients and 3,304 controls) in Chinese. Meta-analysis indicated significant associations for the rs2241766 G allele (OR = 1.14, 95%CI = 1.05–1.24, P = 0.003), rs266729 GG+GT genotypes (OR = 0.80, 95%CI = 0.68–0.92, P = 0.003) and rs1501299 GG+TG genotypes (OR = 1.42, 95%CI 1.16–1.75, P = 0.001).

Conclusions

Our results demonstrated ADIPOQ as a pleiotropic locus for metabolic syndrome and its components in the Han Chinese population.     

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.     

Low Serum Creatine Kinase Levels in Breast Cancer Patients: A Case-Control Study

Background

Previous studies provide an ambiguous picture of creatine kinase (CK) expression and activities in malignancy. The aim of this study was to investigate the role of serum CK level in breast cancer patients.

Patients and Methods

823 female patients diagnosed with breast cancer were consecutively recruited as cases, and 823 age-match patients with benign breast disease were selected as controls. Serum CK was analyzed by commercially available standardized methods.

Results

Serum CK level was significantly associated with breast cancer (P = 0.005) and subtypes of breast cancer, including breast cancer with diameter>2 cm (P = 0.031) and stage IIIbreast cancer (P = 0.025). The mean serum CK level in patients with>2 cm tumor was significantly lower than that in≤2 cm (P = 0.0475), and the mean serum CK level of stage III breast cancer patients was significantly lower than that of stage I and II breast cancer patients (P = 0.0246). Furthermore, a significant difference (P = 0.004) was observed between serum CK level and ERBB2+breast cancer not other molecular subtypes.

Conclusions

Serum CK levels in cases was significantly lower compared with controls. Notably, our results indicated for the first time that there was a negative correlation between serum CK levels and breast cancer stage. Serum CK level, which may reflect the status of host immunity, may be an important factor in determining breast cancer development and progression.     

Genetic Variants in MUC4 Gene Are Associated with Lung Cancer Risk in a Chinese Population

Mucin MUC4, which is encoded by the MUC4 gene, plays an important role in epithelial cell proliferation and differentiation. Aberrant MUC4 overexpression is associated with invasive tumor proliferation and poor outcome in epithelial cancers. Collectively, the existing evidence suggests that MUC4 has tumor-promoter functions. In this study, we performed a case-control study of 1,048 incident lung cancer cases and 1,048 age- and sex frequency-matched cancer-free controls in a Chinese population to investigate the role of MUC4 gene polymorphism in lung cancer etiology. We identified nine SNPs that were significantly associated with increased lung cancer risk (P = 0.0425 for rs863582, 0.0333 for rs842226, 0.0294 for rs842225, 0.0010 for rs2550236, 0.0149 for rs2688515, 0.0191 for rs 2641773, 0.0058 for rs3096337, 0.0077 for rs859769, and 0.0059 for rs842461 in an additive model). Consistent with these single-locus analysis results, the haplotype analyses revealed an adverse effect of the haplotype “GGC” of rs3096337, rs859769, and rs842461 on lung cancer. Both the haplotype and diplotype “CTGAGC” of rs863582, rs842226, rs2550236, rs842225, and rs2688515 had an adverse effect on lung cancer, which is also consistent with the single-locus analysis. Moreover, we observed statistically significant interactions for rs863582 and rs842461 in heavy smokers. Our results suggest that MUC4 gene polymorphisms and their interaction with smoking may contribute to lung cancer etiology.