Prognostic value of PRL-3 overexpression in early stages of colonic cancer

High expression of phosphatase of regenerating liver (PRL-3) has been implicated in cancer invasion and metastasis, indicating a close link between PRL-3 and cancer development. The aim was to investigate the significance of PRL-3 expression in the prognosis of colonic cancer. Expression of PRL-3 protein in tissue slides obtained from surgical resection of primary colonic cancer was measured by immunohistochemistry using a specific anti-PRL-3 monoclonal antibody. Archived tissue specimens from 273 colonic cancers and 236 matched specimens of adjacent normal colonic mucosa with a median follow-up of 57 months were examined. Multivariate analysis showed that PRL-3 was an independent prognostic marker for disease-free survival [DFS; hazard ratio (HR) 1.538, P = 0.035]. More importantly, the expression of PRL-3 showed significant negative correlation with DFS (P = 0.018) in patients in the early stages (stage I and II). Patients with high levels of PRL-3 expression in the adjacent normal mucosa also had a significant worse survival rate (DFS 0.0% versus 74.4%, P = 0.001), and PRL-3 expression remained an independent prognostic marker for DFS (HR 3.0, 95% confidence interval 1.7, 5.3, P < 0.001). PRL-3 may predict poor survival and act as a promising biomarker for individualized therapy for patients with colonic cancer, especially for those diagnosed at an early stage.