GAB1 and hepatocellular carcinoma: To evaluate whether GRB2 and GAB1 protein expression was associated with clinicopathological features of patients with HCC, we correlated IRS of GRB2 and GAB1 proteins with tumor stage, tumor grade, serum AFP level, presence of cirrhosis, underlying liver disease including alcohol abuse, viral hepatitis B and C, sex, and age (Table 1).