Alternatively, the targeting of alpha-fetoprotein (AFP) was carried out through monoclonal antibodies against AFP conjugated with Quantum Dots, AFP-QD590 [143], in order to study the accumulation and retention of AFP-QD at the site of xenografted hepatocellular cancer tumors, even if, to date, this probe was used only in ex vivo fluorescence imaging procedures. The gene discussed is AFP; the disease is hepatocellular carcinoma.