REG1A and hepatocellular carcinoma: HBV X protein (HBx), encoded by HBV X-gene, has been implicated to play a multifunctional oncogenic role in the development of HBV-associated HCC, such as promoting cell cycle progression, increasing cellular migration, regulating apoptotic process, inactivating negative growth regulators and inhibiting nucleotide excision repair of damaged cellular DNA [3, 4].