In the samples evaluated with immunohistochemistry, PRL-3 was expressed in tissue from primary prostate cancer tumors, which is in accordance with Wang et al. [24], who performed a screening of different human cancers for protein expression of PRL-3 using immunohistochemistry, and found PRL-3 protein in 5/53 (9.4 %) prostate cancer samples. This evidence concerns the gene PTP4A3 and prostate cancer.