KRT18 and fibrosis: Results: Biochemical analyses revealed significant increases in plasma alanine aminotransferase (ALT), cytokeratin-18 (CK-18), and malondialdehyde (MDA) levels, as well as liver transforming growth factor-beta (TGF-β), YAP1, and MDA levels, in the MTX-induced fibrosis group in comparison to the control group (p < 0.05).