Background: Published evidence suggests that the rs2233678 (-842 G>C) polymorphism in the PIN1 (peptidyl-prolyl cis/trans somerase NIMA-interacting 1) promoter region may be associated with cancer risk; however, the conclusion is still inconclusive.
Methods: We conducted a meta-analysis to determine whether -842 G>C polymorphism was associated with cancer risk. Odds ratio (OR) and 95% confidence intervals (95% CI) were used to assess the strength of association. Genotype distribution data and adjusted ORs were collected to calculate the pooled ORs. Meta-regression was conducted to detect the source of heterogeneity. Publication bias was evaluated by Egger's test and Begg's test.
Results: A total of 11 eligible studies, including 9280 participants, were identified and analyzed. Overall, we found that carriers of the -842 C allele were associated with significantly decreased cancer risk (C vs. G, OR = 0.750, 95% CI: 0.639-0.880, P(heterogeneity )= 0.014, estimated by genotype distribution data; CC+GC vs. GG, OR = 0.668, 95% CI: 0.594-0.751, P(heterogeneity) = 0.638, estimated by adjusted ORs). No evidence of publication bias was observed. Meta-regression revealed that ethnicities (p = 0.021) and sample size (p = 0.02) but not sources of control (p = 0.069) were the source of heterogeneity.
Conclusion: These results suggest that the PIN1 rs2233678 (-842 G>C) polymorphism significantly reduces cancer risk.