CCL5-403, CCR5-59029, and Delta32 polymorphisms and cancer risk: a meta-analysis based on 20,625 subjects

Associations between CCL5-403, CCR5-59029, and Delta32 polymorphisms and cancer risk are inconclusive. To derive a more precise estimation of the association, we performed a meta-analysis by searching PubMed, EMBASE, Google scholar, and WanFang databases. A total of 20 eligible articles with 39 studies were included. Of those studies, there were 21 studies for CCR5-Delta32 polymorphism, 9 studies for CCR5-59029 polymorphism, and 9 studies for CCL5-403 polymorphism. Combined analysis revealed no associations between these polymorphisms and cancer risk. However, subgroup analysis by ethnicity suggested that CCR5-59029 polymorphism was associated with the risk of cancer among Asian populations (A vs. G: odds ratio (OR)=1.36, 95 % confidence interval (CI) 1.13-1.65, P H=0.27; AA vs. GG: OR=2.07, 95 % CI 1.37-3.12, P H=0.17; GA+AA vs. GG: OR=1.35, 95 % CI 1.03-1.77, P H=0.92; AA vs. GA+GG: OR=1.98, 95 % CI 1.01-3.88, P H=0.08), but not among Caucasian populations. CCL5-403 polymorphism was associated with the risk of cancer among African populations (A vs. G: OR=0.68, 95 % CI 0.55-0.83, P H=0.14; AA vs. GG: OR=0.51, 95 % CI 0.33-0.77, P H=0.52; AG vs. GG: OR=0.58, 95 % CI 0.42-0.80, P H=0.14; AG+AA vs. GG: OR=0.56, 95 % CI 0.41-0.75, P H=0.13), but not among Caucasian populations and Asian populations. Overall, this meta-analysis indicated that CCR5-Delta32 was not associated with the risk of cancer. CCR5-59029 polymorphism contributed to cancer risk among Asian populations, and CCL5-403 polymorphism was associated with the decreased risk of cancer among African populations.