GCDH and hepatocellular carcinoma: GCDH overexpression inhibited HCC cell proliferation, induced G1 arrest, suppressed colony formation, and reduced 5-ethynyl-2′-deoxyuridine (EdU) incorporation, while GCDH knockdown had opposing effects (Fig. 3C to G and Fig. S3A to F), highlighting its antiproliferative role in HCC.