Summary and Future Directions: In summary, research on CHAC1 in kidney cancer, particularly ccRCC, reveals its complex, stage-dependent dual role: it may possess tumor-suppressive functions in the overall tumor context (low expression predicts poor prognosis), while its upregulation in late-stage/high-grade, aggressive ccRCC becomes a strong marker of poor prognosis. This evidence concerns the gene CHAC1 and nonpapillary renal cell carcinoma.