AFP and cancer: The protein expression of PTP4A3/PRL-3 was significantly correlated with tumor differentiation (P < 0.0001), serum AFP (P = 0.0118), high serum PIVKA-II (P = 0.0214), hepatic vein invasion (P = 0.0374), tumor vascular invasion (P = 0.0198), and advanced cancer stages (P = 0.0047).