PRL-1 plays a critical role in development or progression of cancers, such as cell growth, migration and invasion [34], [35], however, we also found PRL-1 downregulated in colon tissues samples compared with normal colon tissue, In fact, the expression of PRLs, reported by Ying Wang et al., was undetectable in the normal colon and in colonic adenoma tissues. Here, PTP4A1 is linked to cancer.