NUAK1 and hepatocellular carcinoma: Although our study demonstrated that GSK3β regulates the expression of PD-L1 at the transcriptional level and revealed another form of regulation of GSK3β on PD-L1 expression, we cannot rule out the possibility that NUAK1 could inhibit PD-L1 proteasome degradation through inhibiting the activity of GSK3β in HCC cells.