ALDH1A1 and hepatocellular carcinoma: Previous research has shown that the isolation of hepatocellular CSC (HCC‐CSC) can be performed using cell surface stemness‐associated markers, such as the transmembrane glycoprotein CD133, alpha fetoprotein (AFP), or aldehyde dehydrogenase isoform 1A1 (ALDH1A1), which have been used for further HCC‐CSC classification into different prognostic subtypes (Dai et al., 2018; Ma et al., 2008a).