Previously, we have shown that a cancer associated-PRL-3 intracellular phosphatase is a potential therapeutic target for PRL-3 antibody therapy. PRL-3 has recently emerged as a potentially useful biomarker for cancer prognosis, particularly the prediction of cancer metastasis (Matsukawa et al, 2010, Ren et al, 12 2009). Here we demonstrate that PRL-3 can act as an independent prognostic marker for cancers.