Association of serum leptin with breast cancer: A meta-analysis.

BACKGROUND: Accumulating evidence has demonstrated that leptin is associated to the tumorigenesis and progression of breast cancer (BC). However, these studies remain inconsistent. Thus, a meta-analysis was conducted to investigate the role of leptin in the patients with BC. METHOD: A systematic search in PubMed, Embase, ISI Web of Science, and Chinese National Knowledge Infrastructure (CNKI) databases was conducted up to September 1, 2017. The standardized mean difference (SMD) with 95% confidence interval (CI) was applied to pool the effect size. A funnel plot and Egger test were used to evaluate publication bias. RESULTS: Finally, 43 eligible studies were included in the current meta-analysis. Overall, serum leptin levels in BC cases were significantly higher compared with the controls (SMD = 0.61, P <.0001). When subgroup analyses were restricted to ethnicity and menstrual status, higher serum leptin concentration was also detected in patients with BC. Moreover, BC cases with body mass index (BMI) >25 indicated significantly higher serum leptin levels (SMD = 1.48, P = .034). Furthermore, the BC cases with lymph node metastases showed significantly higher serum leptin concentration (SMD = 0.53, P = .015). CONCLUSION: The present meta-analysis suggests that the serum leptin may profiles as a pivotal role in the pathogenesis and metastasis of BC. In addition, leptin will provide useful information for a therapeutic target to treat BC.

The Role of Catalase C262T Gene Polymorphism in the Susceptibility and Survival of Cancers.

Catalase (CAT), one antioxidant enzyme, may provide resistance against many diseases. Many previous studies reported predictive and prognostic values of CAT C262T polymorphism in cancers, with divergent results. This study aimed to summarize the overall relationships between CAT C262T polymorphism and cancer risk or survival. A total of 27 eligible publications were included in susceptibility analysis, while 8 publications contained survival outcomes. The results revealed significant relationship between CAT C262T polymorphism and cancer risk(TT + CT vs CC: OR = 1.05, 95%CI = 1.00-1.10, P = 0.036), subgroup analyses indicated the CAT C262T polymorphism was significantly correlated with an increased risk for prostate cancer (TT vs CC + CT: OR = 1.43, 95%CI = 1.20-1.70, P < 0.001) and increased risk among Caucasians (TT vs CC + CT: OR = 1.19, 95%CI = 1.09-1.31, P < 0.001), while no associations between the polymorphism and Asian or mixed population were established. In the survival analysis, no interactions were identified between this polymorphism and cancer survival (TT + CT vs CC: HR = 1.37, 95%CI = 0.70-2.70, P = 0.36). In conclusion, the CAT C262T polymorphismmay be a candidate markerfor cancer risk with type-specific and population-specific effects but not a fine prognostic factor for cancer survival.

Impact of CYP1A1 Polymorphisms on Susceptibility to Chronic Obstructive Pulmonary Disease: A Meta-Analysis.

OBJECTIVE: Several studies have evaluated the association between CYP1A1 polymorphisms and the susceptibility of chronic obstructive pulmonary disease (COPD) with inconclusive results. We performed the first comprehensive meta-analysis to summarize the association between CYP1A1 polymorphisms and COPD risk. METHOD: A systematic literature search was conducted (up to April 2015) in five online databases: PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), WeiPu, and WanFang databases. The strength of association was calculated by odds ratio (OR) and corresponding 95% confidence interval (CI). RESULTS: Seven case-control studies with 1050 cases and 1202 controls were included. Our study suggested a significant association between the MspI polymorphism and COPD risk (CC versus TC + TT: OR = 1.57, CI: 1.09-2.26, P = 0.02; CC versus TT: OR = 1.73, CI: 1.18-2.55, P = 0.005). For the Ile/Val polymorphism, a significant association with COPD risk was observed (GG versus AG + AA: OR = 2.75, CI: 1.29-5.84, P = 0.009; GG versus AA: OR = 3.23, CI: 1.50-6.93, P = 0.003; AG versus AA: OR = 1.39, CI: 1.01-1.90, P = 0.04). Subgroup analysis indicated a significant association between the MspI variation and COPD risk among Asians (CC versus TC + TT: OR = 1.70, CI: 1.06-2.71, P = 0.03; CC versus TT: OR = 1.84, CI: 1.11-3.06, P = 0.02). CONCLUSION: The MspI and Ile/Val polymorphisms might alter the susceptibility of COPD, and MspI polymorphism might play a role in COPD risk among Asian population.

Contribution of Macrophage Migration Inhibitory Factor -173G/C Gene Polymorphism to the Risk of Cancer in Chinese Population.

BACKGROUND: Macrophage migration inhibitory factor (MIF) -173G/C (rs755622) gene polymorphism has been associated with cancer risk. Previous studies have revealed that MIF -173G/C gene polymorphism may increase cancer in the Chinese population, while results of individual published studies remain inconsistent and inconclusive.We performed this meta-analysis to derive a more precise estimation of the relationship. MATERIALS AND METHODS: We conducted a search on PubMed, Embase, MEDLINE, Cochrane Library ,Chinese National Knowledge Infrastructure (CNKI), Wanfang, Weipu on Dec 31, 2014.Odds ratio (OR) and 95% confidence interval (95% CI) were used to assess the association. A total of eight studies including 2,186 cases and 2,285 controls were involved in this meta-analysis. RESULTS: The pooled results indicated the significant association between MIF -173G/C polymorphism and the risk of cancer for Chinese population (CC + CG vs GG: OR=1.14, 95%CI=1.02-127, pheterogeneity<0.01; P =0.023; CC vs CG+GG: OR=1.12, 95%CI=1.02- 1.23, pheterogeneity< 001; P =0.017;CC vs GG: OR=1.18, 95%CI=1.04-1.33, pheterogeneity<001; P =0.008; CG vs GG:OR=1.03, 95%CI=0.91-1.15, pheterogeneity<001; P =0.656; C vs G:OR=1.24, 95%CI=1.14-1.25, pheterogeneity<001; P <001). Subgroup analysis showed that in patients with "solid tumors", heterogeneity was very large (OR=0.94,95%CI=0.83-1.06,pheterogeneity=0.044; p=0.297). Within "non-solid tumors", the association became even stronger (OR=6.62, 95 % CI=4.32-10.14, pheterogeneity<0.001; p <0.001). CONCLUSIONS: This study suggested that MIF ?173G/C gene polymorphism may increase increase cancer in the Chinese population.Furthermore, more larger sample and representative population-based casees and well-matched controls are needed to validate our results.