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. This evidence concerns the gene PROM1 and intrahepatic cholangiocarcinoma.