In clear cell renal cell carcinoma (ccRCC), CHAC1 exhibits stage-specific functional duality: downregulation in early-stage tumors correlates with adverse prognosis (suggesting tumor-suppressive activity), whereas elevated expression in advanced ccRCC (G3-G4/Stage III-IV) associates with increased mortality (indicating adaptive pro-survival adaptation). Here, CHAC1 is linked to nonpapillary renal cell carcinoma.