Zexin Chen

Gender susceptibility for cigarette smoking-attributable lung cancer: A systematic review and meta-analysis

OBJECTIVES As the primary cause of lung cancer, whether smoking confers the same risk of lung cancer for women as men is unclear. Therefore, we aimed to compare male and female susceptibility for cigarette smoking-attributable lung cancer. METHODS A systematic review and meta-analysis was conducted by searching articles published up to July 2013 in three online databases (MEDLINE, EMBASE, and Cochrane Database). All studies estimated the association of cigarette smoking with the risk of lung cancer between men and women, respectively. A random effects model with inverse variance weighting was used to pool data. Male to female ratio of relative risk (RRR) was calculated to compare male and female susceptibility for cigarette smoking-attributable lung cancer. RESULTS 47 articles containing 404,874 individuals were included in the final analysis. Compared with non-smokers, male to female RRR was 1.61 (95%CI: 1.37, 1.89) among current smokers. Based on pathological type, adenocarcinoma had the highest RRR (1.42; 95%CI: 0.86, 2.35), followed by squamous cancer and small cell lung cancer. Furthermore, compared with non-smoking men, current smoking men had higher risk of lung cancer than women in spite of smoking quantity, smoking duration or years since quitting. CONCLUSIONS These findings indicated that males had higher susceptibility for cigarette smoking-attributable lung cancer than females. It is contradicted with traditional opinion that females would be more easily suffered from cigarette smoking-attributable health problems than males. Hence, tobacco control is very crucial in both males and females.

Tissue microRNA-21 expression predicted recurrence and poor survival in patients with colorectal cancer – a meta-analysis

Objective MicroRNA-21 (miR-21) has been shown to play an important role in cancer prognosis. We performed a meta-analysis to evaluate the prognostic effect of miR-21 from tissues and serum on survival of the patients with colorectal cancer (CRC). Methods Relevant studies were identified by searching PubMed, Embase, and Cochrane Library. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) of total and subgroup analyses, for overall survival (OS) and disease-free survival (DFS), were calculated to investigate the association between miR-21 expression and CRC prognosis. Results Our analysis included eleven studies (3,669 subjects). In addition, four studies explored the association between miR-21 and DFS, and ten studies focused on the prognostic value of miR-21 for OS. Our results indicated that increased miR-21 expression of tissues predicted both poor DFS and OS in patients with CRC (DFS: HR =1.59, 95% CI =1.20–2.10; OS: HR =1.53, 95% CI =1.23–1.90). Consistent results were observed among colon cancer and quantitative real-time polymerase chain reaction subgroups. Conclusion Meta-analysis indicated that miR-21 predicted recurrence and poor survival in patients with CRC. miR-21 may be more suitable to predict cancer prognosis in colon cancer patients.

Polymorphisms of inflammation-related genes and colorectal cancer risk: a population-based case–control study in China

The previous studies found that chronic inflammation related to an increased risk of colorectal cancer (CRC). This study aims to explore the associations of polymorphisms in inflammation‐related genes (IL10, IL10RA, IL6R, TNFRSF1A, TNFRSF1B, LTA and IL4) and their interactions with the risk of colorectal cancer among Chinese population. A population‐based case–control study including 299 cases and 296 controls was conducted from January 2001 to December 2009. Multivariate unconditional logistic regression was used to analyse the association of nine SNPs in inflammation‐related genes with the risk of CRC, colon cancer and rectal cancer, respectively. Generalized multifactor dimensionality reduction (GMDR) was implemented to explore the gene–gene interactions among all SNPs on CRC. A decreased risk of colorectal cancer in subjects with rs1800872 AC genotype of IL10 (OR = 0.643, 95%CI = 0.453, 0.912) or AC/CC genotype (OR = 0.636, 95%CI = 0.457, 0.885) was observed, compared with those with AA genotype. Meanwhile, similar associations were observed between rs1800872 and rectal cancer. Additionally, in rs1061624 of TNFRSF1B gene, AG genotype (OR=0.566; 95% CI= 0.362, 0.885) and AG/GG genotype (OR=0.638; 95% CI=0.420, 0.971) were significantly associated with a decreased risk of rectal cancer, respectively. Our findings indicated that mutants in IL10 and TNFRSF1B genes may change the CRC risk. However, there is no interaction between inflammation‐related genes on CRC risk.

RPSA Gene Mutants Associated with Risk of Colorectal Cancer among the Chinese Population

The primary aim of this study was to evaluate the relationship of single nucleotide polymorphisms (SNPs) in ribosomal protein SA (RPSA) gene with colorectal cancer (CRC). A case-control study including 388 controls and 387 patients with CRC was conducted in a Chinese population. Information about socio-demography and living behavior factors was collected by a structured questionnaire. Three SNPs (rs2133579, rs2269349, rs7641291) in RPSA gene were genotyped by Illumina SnapShot method. Multiple logistic regression models were used for assessing the joint effects between tea consumption and SNPs on CRC. The subjects with rs2269349 CC genotype had a decreased risk for CRC (OR=0.60; 95%CI = 0.37-0.99), compared with TT/CT genotype after adjustment for covariates. A similar association of rs2269349 with rectal cancer was observed (OR=0.49; 95%CI=0.24-1.00). Further analyses indicated that this SNP could modify the protective effect of tea drinking on CRC. Among the subjects with rs2269349 TT/CT or rs2133579 AA/GA, there was a marginal significantly lower risk of CRC (OR and 95%CI: 0.63 and 0.39-1.01 for rs2269349; 0.64 and 0.40-1.02 for rs2133579) in tea-drinking subjects in comparison to non-tea-drinking subjects. Mutants in the RPSA gene might be associated with genetic susceptibility to CRC and influence the protective effect of tea consumption in the Chinese population.

Relationship of anthropometric measurements to thyroid nodules in a Chinese population

Objective Previous studies have found that overweight and obesity are related to numerous diseases, including thyroid cancer and thyroid volume. This study evaluates the relationship between body size and the presence of thyroid nodules in a Chinese population. Methods A total of 6793 adults and 2410 children who underwent thyroid ultrasonography were recruited in this cross-sectional study in Hangzhou, Zhejiang Province, China, from March to October, 2010. Sociodemographic characteristics and potential risk factors of thyroid nodules were collected by questionnaire. Height and weight were measured using standard protocols. Associations of height, weight, body mass index (BMI) and body surface area (BSA) with the presence of thyroid nodules were evaluated using multiple logistic regression models. Results After adjustment for potential risk factors, an increased risk of thyroid nodule incidence was associated with height (OR 1.15, 95% CI 1.02 to 1.30), weight (OR 1.40, 95% CI 1.24 to 1.58), BMI (OR 1.26, 95% CI 1.11 to 1.42) and BSA (OR 1.43, 95% CI 1.27 to 1.62) in all adults, but most obviously in women. In children, similar associations were observed between risk of thyroid nodule incidence and weight, BMI and BSA, but not height. BSA was the measurement most significantly associated with thyroid nodules in both adults and children. Conclusions This study identified that the presence of thyroid nodules was positively associated with weight, height, BMI and BSA in both women and girls. It suggests that tall, obese individuals have increased susceptibility to thyroid nodules. Trial registration number: NCT01838629.

Social relationships play a role in sleep status in Chinese undergraduate students

The purpose of this study was to examine whether social relationships were associated with sleep status in Chinese undergraduate students. A cross-sectional questionnaire survey was conducted in November 2012 at Huzhou Teachers College, China. The questionnaire involved demographic characteristics, personal lifestyle habits, social relationships and Pittsburgh Sleep Quality Index (PSQI). The associations between social relationships and sleep status were analyzed by using regression models after adjustment for potential factors. Poor sleep quality was prevalent among Chinese undergraduate students. Men tended to have better sleep than women. Lower social stress, better management of stress and good social support were correlated with better sleep status, and stress or support from friends, family and classmates were all related with sleep variables. While only weak associations between number of friends and sleep were detected. The results were consistent in men and women. Educators and instructors should be aware of the importance of social relationships as well as healthy sleep in undergraduates.

Occupational electromagnetic field exposures associated with sleep quality: a cross-sectional study.

Background Exposure to electromagnetic field (EMF) emitted by mobile phone and other machineries concerns half the world’s population and raises the problem of their impact on human health. The present study aims to explore the effects of electromagnetic field exposures on sleep quality and sleep duration among workers from electric power plant. Methods A cross-sectional study was conducted in an electric power plant of Zhejiang Province, China. A total of 854 participants were included in the final analysis. The detailed information of participants was obtained by trained investigators using a structured questionnaire, which including socio-demographic characteristics, lifestyle variables, sleep variables and electromagnetic exposures. Physical examination and venous blood collection were also carried out for every study subject. Results After grouping daily occupational electromagnetic exposure into three categories, subjects with long daily exposure time had a significantly higher risk of poor sleep quality in comparison to those with short daily exposure time. The adjusted odds ratios were 1.68 (95%CI: 1.18, 2.39) and 1.57 (95%CI: 1.10, 2.24) across tertiles. Additionally, among the subjects with long-term occupational exposure, the longer daily occupational exposure time apparently increased the risk of poor sleep quality (OR (95%CI): 2.12 (1.23∼3.66) in the second tertile; 1.83 (1.07∼3.15) in the third tertile). There was no significant association of long-term occupational exposure duration, monthly electric fee or years of mobile-phone use with sleep quality or sleep duration. Conclusions The findings showed that daily occupational EMF exposure was positively associated with poor sleep quality. It implies EMF exposure may damage human sleep quality rather than sleep duration.

The Relationship of TPOAb and TGAb with Risk of Thyroid Nodules: A Large Epidemiological Study

Objective: The association between thyroid hormones, thyroid autoantibodies, and thyroid nodules are still not clear. The cross-sectional study, conducted in Hangzhou, China in 2010, aimed to identify the relationship of thyroid hormones and autoantibodies with thyroid nodules. Methods: Information regarding social demography was collected by a questionnaire. Thyroid hormones (triiodothyronine, thyroxin, free triiodothyronine, free thyroxin, thyrotropin), thyroid autoantibodies (thyroid peroxidase antibody, antithyroglobulin antibody), and thyroid nodules (diagnosed by ultrasonography) was measured in 1271 adults. The association of thyroid hormones and thyroid autoantibodies with thyroid nodules was evaluated using multiple logistic regression models. Results: The prevalence of thyroid nodules among males and females was 29.49% and 33.15%, respectively. The thyroid hormone level in the thyroid nodules group was significantly higher than the non-nodules group (all p values < 0.05), except reversely in TSH (thyroid stimulating hormone) (p = 0.0532) and TGAb (thyroglobulin antibody) (p = 0.0004). High levels of TPOAb (thyroid peroxidase antibody) (OR (Odds Ratio) = 1.51, 95% CI (confidence interval): 0.99–2.30) and TGAb (OR = 2.86, 95% CI: 1.49–5.51) were associated with increased risk of thyroid nodules, compared with corresponding low levels. However, following sub-analyses in two genders, the similar associations were only observed in females (TPOAb: OR = 1.63, 95% CI: 0.99–2.68; TGAb: OR = 3.13, 95% CI: 1.53–6.40). Conclusions: The present study indicated that thyroid autoantibodies were positively associated with the risk of thyroid nodules in Chinese coastal adults.

The Association of Thyroid Nodule with Non-Iodized Salt among Chinese Children

Objective The controversy that iodized salt may increase the risk of thyroid disorders has been aroused in China during the past decade. Most of studies focused on adult rather than children. We aimed to explore whether iodized salt was associated with an increased risk of thyroid nodule in Chinese children. Methods The cross-sectional study was conducted in Hangzhou, China, in 2010. Iodized salt intake, urine iodine concentration (UIC) and thyroid nodule (by ultrasonography) were measured in 3026 children. The associations of iodized salt with thyroid nodule were evaluated using multiple logistic regression models. Results The prevalence of thyroid nodule was 10.59% among Chinese children. Girls (11.89%) had higher prevalence of thyroid nodule than boys (9.26%). No significant association was observed between type of salt and thyroid nodule in pooled samples, boys and girls, respectively. Similar associations were observed between UIC and thyroid nodule. There was no significant association between milk consumption and thyroid nodule as well. Conclusion The present study indicated that non-iodized salt may not increase the risk of thyroid nodules among Chinese children. Similar associations were observed between milk consumption, UIC and thyroid nodules.