Here, we confirm that miR-31 is significantly downregulated in α2δ1+ HCC TICs, and serves as a suppressor of α2δ1+ HCC TICs via targeting ISL LIM Homeobox 1 (ISL1), a transcriptional factor involved in recognition of undifferentiated cardiac progenitors [23, 24]. Here, ISL1 is linked to hepatocellular carcinoma.