Among these 24 genes, TALDO1, PRPS2, PTGES3, RRM2, DAD1, PAICS, PARK7, RPL36AL, SRP14, SSR2, CDC42 have been shown to be down regulated in the presence of metformin in a rat hepatoma line and breast cancer cells [17, 18]. Here, RRM2 is linked to hepatocellular carcinoma.