The previous research on HCC TICs found that we could separate or enrich HCC TICs through specific staining for cell surface markers, such as CD133, CD90 and EpCAM (Yang et al, 2008a, 2008b; Yamashita et al, 2009; Yeh et al, 2009; Yoshikawa et al, 2009; Zhu et al, 2009). Here, PROM1 is linked to hepatocellular carcinoma.