The heterogeneous expression of survivin was further validated in 40 pairs of HCC samples by real time RT-qPCR analysis (Fig. 1C) and an additional independent cohort of 30 pairs of HCC samples by Immunohistochemistry (IHC) (Fig. 1D, 1E and Fig. S1B). This evidence concerns the gene BIRC5 and hepatocellular carcinoma.