By directly pooling genotype distribution data, in overall comparison, we found that the −842 G>C polymorphism was associated with decreased cancer risk, namely the PIN1 −842 C allele significantly reduced cancer risk compared with the −842 G allele (C vs. G, OR = 0.750, 95% CI:0.639–0.880, Pheterogeneity = 0.014, Figure 2). Here, PIN1 is linked to cancer.