RRM2 and hepatocellular carcinoma: We then ranked the HB and HCC patient tumors based on their RRM2 or RRM2B expression and selected tumors ranked top 1/3 and bottom 1/3 for each gene (RRM2high and RRM2Bhigh tumors, respectively) to examine the enrichment of the top ten pathways of PTWAYRRM2 and PTWAYRRM2B in these tumors.