title: Programmed Cell Death-1 Polymorphisms Decrease the Cancer Risk: A Meta-Analysis Involving Twelve Case-Control Studies.
abstract: Programmed cell death-1 (PD-1) plays an important inhibitory role in anti-tumor responses, so it is considered as a powerful candidate gene for individual's genetic susceptibility to cancer. Recently, some epidemiological studies have evaluated the association between PD-1 polymorphisms and cancer risk. However, the results of the studies are conflicting. Therefore, a meta-analysis was performed. We identified all studies reporting the relationship between PD-1 polymorphisms and cancers by electronically searches. According to the inclusion criteria and the quality assessment of Newcastle-Ottawa Scale (NOS), only high quality studies were included. A total of twelve relevant studies involving 5,206 cases and 5,174 controls were recruited. For PD-1.5 (rs2227981) polymorphism, significantly decreased cancer risks were obtained among overall population, Asians subgroup and population-based subgroup both in TT vs. CC and TT vs. CT+CC genetic models. In addition, a similar result was also found in T vs. C allele for overall population. However, there were no significant associations between either PD-1.9 (rs2227982) or PD-1 rs7421861 polymorphisms and cancer risks in all genetic models and alleles. For PD-1.3 (rs11568821) polymorphism, we found different cancer susceptibilities between GA vs. GG and AA vs. AG+GG genetic models, and no associations between AA vs. GG, AA+AG vs. GG genetic models or A vs. G allele and cancer risks. In general, our results firstly indicated that PD-1.5 (rs2227981) polymorphism is associated a strongly decreased risk of cancers. Additional epidemiological studies are needed to confirm our findings.
authors.affiliation: Department of Oncology, Zhongshan Affiliated Hospital of Sun Yat-sen University, Zhongshan, Guangdong 528403, China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Dong
authors.affiliation: Department of Urology, Zhongshan Affiliated Hospital of Sun Yat-sen University, Zhongshan, Guangdong 528403, China.
authors.forename: Mancheng
authors.initials: M
authors.lastname: Gong
authors.affiliation: Department of Pharmacy, The Second People's Hospital of Zhuhai, Zhuhai, Guangdong 519020, China.
authors.forename: Zhirong
authors.initials: Z
authors.lastname: Shi
authors.affiliation: Department of Oncology, Zhongshan Affiliated Hospital of Sun Yat-sen University, Zhongshan, Guangdong 528403, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Xiao
authors.affiliation: Department of Oncology, Zhongshan Affiliated Hospital of Sun Yat-sen University, Zhongshan, Guangdong 528403, China.
authors.forename: Junkai
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Oncology, Zhongshan Affiliated Hospital of Sun Yat-sen University, Zhongshan, Guangdong 528403, China.
authors.forename: Jiewen
authors.initials: J
authors.lastname: Peng
mesh_terms: D000483:Alleles; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008957:Models, Genetic; D009363:Neoplasm Proteins / Q000235:genetics*; D009369:Neoplasms / Q000235:genetics*; D011110:Polymorphism, Genetic; D061026:Programmed Cell Death 1 Receptor / Q000235:genetics*
chemical_list: D009363:Neoplasm Proteins; C105992:PDCD1 protein, human; D061026:Programmed Cell Death 1 Receptor