CDK1 and hepatocellular carcinoma: For instance, circ-IGF1R expression level is raised in HCC, which can promote proliferation and reduce the apoptosis in HCC by activating PI3K/AKT pathway (21); circ_0003418, a tumor-suppressive circRNA in HCC, can enhance the sensitivity of HCC cells to cisplatin by inhibiting Wnt/β-catenin pathway (22); circ-ADD3 promotes EZH2 degradation through CDK1-mediated ubiquitination, thus inhibiting the metastasis of HCC cells (23).