Objective To investigate association between –174C/G genetic polymorphism of interleukin-6 (IL-6) and susceptibility to gastric cancer by conducting a meta-analysis. Methods Such databases as PubMed, Embase, The Cochrane Library, Web of Science, CNKI, VIP, and Wanfang Data were searched from inception to January 2017 to collect case-control studies about the correlation between the –174C/G genetic polymorphism of IL-6 and susceptibility to gastric cancer. For the population genotype distributions of both the gastric cancer group and the control group, their odds ratios (OR) and 95% confidence intervals (CI) were taken as the effect indexes were applied to conduct meta-analysis in the homozygote model (CC vs. GG), heterozygote model (GC vs. GG), dominant model (CC+CG vs. GG), recessive model (CG+GG vs. CC), and allelic genetic model (C vs. G). Two reviewers independently screened the literatures, extracted the data, and evaluated the quality of the included studies. The meta-analysis was performed using Stata 12.0 software. Results Thirteen articles were included in the final meta-analysis, covering a total of 2 062 gastric cancer cases and 3 152 controls. The results of meta-analysis showed that there was no correlation between the IL-6 –174C/G genetic polymorphism and the risk of gastric cancer〔CC vs. GG: OR=1.33, 95% CI (0.92, 1.94); GC vs. GG: OR=1.32, 95% CI (0.96, 1.82); CC+CG vs. GG: OR=1.32, 95% CI (0.97, 1.80); CG+GG vs. CC: OR=0.89, 95% CI (0.67, 1.17); C vs. G: OR=1.22, 95% CI (0.98, 1.54)〕. But the results of the subgroup analysis showed there was a significant association between the IL-6 –174 C/G genetic polymorphism and the risk of gastric cancer in Asians〔CC vs. GG: OR=1.80, 95% CI (1.29, 2.50); GC vs. GG: OR=1.51, 95% CI (1.20, 1.90); CC+CG vs. GG: OR=1.60, 95% CI (1.30, 1.96); CG+GG vs. CC: OR=0.60, 95% CI (0.44, 0.83); C vs. G: OR=1.59, 95% CI (1.24, 2.03)〕. However, no association was found in Europeans〔CC vs. GG: OR=1.11, 95% CI (0.90, 1.39); GC vs. GG: OR=1.16, 95% CI (0.98, 1.37); CC+CG vs. GG: OR=1.12, 95% CI (0.96, 1.32); CG+GG vs. CC: OR=1.07, 95% CI (0.88, 1.30); C vs. G: OR=1.04, 95% CI (0.78, 1.41)〕 . Conclusion IL-6 –174C/G genetic polymorphism is associated with susceptibility to gastric cancer in Asians, which is not associated with susceptibility to gastric cancer in Europeans.
Objective To study the correlation between preoperative serum thyroid stimulating hormone (TSH) level and the malignant risk of thyroid nodules. Methods This study retrospectively analyzed the medical records of 959 patients with thyroid nodules. Ststistical analysis was conducted by SPSS 17.0 software. Results There were 959 patients with thyroid nodules, of which 746 cases were benign, and 213 cases were diagnosed as thyroid papillary carcinoma (PTC). The preoperative TSH level of PTC patients was higher than that with benign nodules [(2.32±1.65) mU/L vs. (1.76±1.20) mU/L, P<0.001]. Moreover, the higher preoperative TSH level was, the higher risk of diagnosed as PTC would be. There was no correlation between the preoperative TSH level and tumor diameter, number of lesions, and lymph nodes metastasis in PTC (P>0.05). Logistic regression analysis showed that, the preoperative TSH level was an independent risk factor for PTC [OR=1.315, 95% CI was (1.171, 1.477), P<0.001]. The best critical value of TSH in the PTC diagnosis was 1.575 mU/L. At this point, the sensitivity was 62.0%, the specificity was 53.4%, and the area under the receiver operating characteristic (ROC) curve was 0.602 (P<0.001). Conclusion There is a certain correlation between preoperative TSH level and malignant risk of thyroid nodules, and the risk increases with the raise of preoperative TSH level.