Recently, the diagnostic value of GPC3 in HCC has been gradually recognized: GPC3 is specifically expressed in liver cancer tissues, and presents as soluble GPC3 (sGPC3) in peripheral blood of HCC patients, while its expression is not detected in the liver tissues of healthy adults, or pathological samples of fatty liver, or liver with cirrhosis, hepatitis, or injury, suggesting that GPC3 is a more reliable tumor marker than alpha-fetoprotein (AFP). The gene discussed is AFP; the disease is hepatocellular carcinoma.