Interestingly, amplification of cyclin D1 gene expression, and overexpression of cyclin D1 protein has been detected in HCC, suggesting a potentially important link between URGCP/URG4, cell cycle regulation and HCC progression; though the molecular mechanism of how URGCP/URG4 regulates the expression of cyclin D1 is unclear [21], [22]. This evidence concerns the gene CCND1 and hepatocellular carcinoma.