CD133, a pentaspan transmembrane glycoprotein, is overexpressed in various solid tumors, including HCC, PC, gastric cancer, and intrahepatic cholangiocarcinomas.85,86 Moreover, the high expression of CD133 in HCC cells corresponds with higher stage tumors, indicating a poor prognosis for most patients.87,88 These results indicate that CD133 is a reasonable target for immunotherapy in patients with advanced CD133-positive tumors. The gene discussed is PROM1; the disease is gastric cancer.