GRB2 and hepatocellular carcinoma: Since GAB1 has the highest k-coreness suggesting its central localization in HCC related network, and the interaction between GRB2 and GAB1 has the largest edge-betweenness implying it may be biologically important to the function of HCC related network, we performed the experimental validation to evaluate the clinical significance of GRB2 and GAB1 in HCC.