VHL and nonpapillary renal cell carcinoma: To address the potential role of ALDH2 in cytotoxicity of anthracyclines in ccRCC cells, we silenced ALDH2 expression in RCC4/VHL cells, and found that the reduction of ALDH2 suppressed the proliferation of these cells (Supplementary Fig. 5a), although the ALDH2 knockout did not affect the proliferation of the primary MEF cells (Supplementary Fig. 5b).