ALDH2 and cancer: As shown in Supplementary Fig. 8a–c, lower mRNA expression of VHL, HNF-4α and ALDH2 were found in cancer tissues compared to their corresponding adjacent tissues, and there was a positive correlation between VHL and HNF-4α mRNA (Supplementary Fig. 8d) and between HNF-4α and ALDH2 mRNA (Supplementary Fig. 8e).