To further verify the role of GPR31, we used siRNA to knockdown GPR31 in both bel-7402 and Huh7 cells (Fig. 7d-f), and found that EMT and MMPs were inhibited when GPR31 was suppressed, indicating that GPR31 may play an important role in 12-HETE induced HCC recurrence (Fig. 7g and h, Additional file 4: Fig. S3A and B). Here, GPR31 is linked to hepatocellular carcinoma.