S100A4 and keratoconus: Similar to other studies comparing entire KC and normal corneas, our data of cone versus normal showed increased epithelial proteins including vimentin, S100A4, KRT12 and 14, decorin, IL18 (interleukin-18); and reduced proteins included transketolase, pyruvate transferase, LOX (lysyl oxidase), ZO-1 and SOD (superoxide dismutase).