KRT18 and renal cell carcinoma: In addition, Spp1, which encodes secreted phophoprotein 1, and Cytokeratins (Krt7, Krt8, Krt18), both implicated in several kidney pathologies, among them renal cell carcinoma (RCC), found also to increase immediately after induction of the injury and remained upregulated till day 4, when they lowered to the normal levels.