CYP27A1 and neoplasm: However, 27HC supplementation neutralized the inhibition of lung metastasis by DHCR7 knockdown, whereas the injection of the CYP27A1 inhibitor GW297X in cells overexpressing TMEM147 restrained tumor progression and metastasis, and supplementation with 27HC offset the effect of GW297X (Fig. S3g and S3h).