title: Programmed death-1 (PD-1) rs2227981 C > T polymorphism is associated with cancer susceptibility: a meta-analysis.
abstract: Several studies have focused on the correlation between the programmed death-1 (PD-1) rs2227981 C > T polymorphism and the risk of cancer; however, the results of such studies remain conflicting. To address this gap, we performed this meta-analysis to identify the potential association. Search strategies were performed in PubMed and EMBASE using appropriate terms. In total, 2,977 cancer cases and 2,642 controls from seven publications were recruited in our study. According to the seven eligible publications, the odds ratios (ORs) and 95% confidence intervals (CIs) on the risk of cancer for the TT vs. CC and TT vs. CT+CC genotypes were 0.67 and 0.50-0.91 and 0.65 and 0.47-0.90, respectively. In a subgroup analysis by cancer type, PD-1 rs2227981 C > T polymorphism was associated with a significantly decreased risk of breast cancer (OR, 0.82; 95% CI, 0.71-0.95; P = 0.009 for T vs. C and OR, 0.76; 95% CI, 0.63-0.92; P = 0.005 for TT+CT vs. CC) and of other cancer (OR, 0.58; 95% CI, 0.36-0.92; P = 0.004 for TT vs. CT+CC). In a subgroup analysis by ethnicity, a significant decreased cancer risk was identified among Asians (OR, 0.74; 95% CI, 0.63-0.86; P < 0.001 for T vs. C and OR, 0.71; 95% CI, 0.59-0.87; P = 0.001 for TT+CT vs. CC) and among Caucasians (OR, 0.66; 95% CI, 0.44-0.99; P = 0.047 for TT vs. CT+CC). These findings highlight the fact that the T allele of PD-1 rs2227981 C > T polymorphism modestly decreases the susceptibility of cancer. Nevertheless, further large and well-designed studies are needed to enrich the evidence of this association.
authors.affiliation: Department of Thoracic Surgery, The Union Clinical Medical College of Fujian Medical University Fuzhou, Fujian Province, China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Cardiology, The People's Hospital of Xishuangbanna Dai Autonomous Prefecture Jinghong, Yunnan Province, China.
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Emergency, Affiliated Jintan People's Hospital of Jiangsu University Jintan, China.
authors.forename: Heping
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Anesthesiology, The People's Hospital of Xishuangbanna Dai Autonomous Prefecture Jinghong, Yunnan Province, China.
authors.forename: Pinghua
authors.initials: P
authors.lastname: Liu
authors.affiliation: Department of Cardiothoracic Surgery, Affiliated People's Hospital of Jiangsu University Zhenjiang, Jiangsu Province, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Cardiothoracic Surgery, Affiliated People's Hospital of Jiangsu University Zhenjiang, Jiangsu Province, China.
authors.forename: Haiyong
authors.initials: H
authors.lastname: Gu
authors.affiliation: Department of Thoracic Surgery, The Union Clinical Medical College of Fujian Medical University Fuzhou, Fujian Province, China.
authors.forename: Shuchen
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Thoracic Surgery, The Union Clinical Medical College of Fujian Medical University Fuzhou, Fujian Province, China.
authors.forename: Mingqiang
authors.initials: M
authors.lastname: Kang
keywords: Polymorphism; cancer risk; programmed death-1