SMAD3 and hepatocellular carcinoma: Furthermore, we observed that TERT promoter mutation upregulated the expression of Smad3 at translational level (Figure 6H and I) rather than transcriptional level (Figure S5D) to respond to PLK1 inhibitors in HCC mut cells, indicating that TERT promoter mutation may not only enhance the level of TERT itself but also regulate the levels of other genes.