SIRT1 and hepatocellular carcinoma: In HCC, SIRT1 inhibition by protocadherin 20 promotes ferroptosis via reducing the expression of SLC7A11, GPX4 and GSH, while increasing MDA, ROS and intracellular iron levels, resulting in a significant decrease in cell viability, colony-forming ability, and the growth and size of tumor (Jun et al., 2023).