Thus, these results showed that HOXA2 and additional transcription factors mediate the regulatory effect of the risk SNP at the 19q13 locus on PCAT19 and CEACAM21 and eventually lead to aggressive prostate cancer susceptibility [73] and also raise new questions of how these transcription factors compete for the binding to the SNP region. This evidence concerns the gene CEACAM21 and prostate carcinoma.