C1S and neoplasm: Furthermore, we observed the presence of this specific cluster of tumor cells in four additional scRNA sequencing datasets (Fig. S6B-E) and the Renji TMA cohort (Fig. 6E), characterized by elevated expression levels of PLOD2, SAA1, C1R, and C1S. Importantly, the expression of these genes increased with the advancement of TNM stage in ccRCC patients (Fig. 6F-M), suggesting that they could serve as a valuable prognostic indicator in ccRCC.