For instance, circSMAD2 inhibits the migration, invasion, and EMT of HCC cells by targeting miR-629 [23] and markedly associates with the differentiation degree; circC3P1 acts as a tumor suppressor via enhancing PCK1 expression by sponging miR-4641 to inhibit HCC growth and metastasis. Here, PCK1 is linked to hepatocellular carcinoma.