CYP17A1 and breast cancer: Moreover, upon analyses of The Cancer Genome Atlas Breast Invasive Carcinoma (TCGA-BRCA) RNA-Seq dataset, we reported that the amplification of the StAR gene, but not of CYP19A1 or other steroidogenic enzyme genes such as cytochrome P450 family 11 subfamily A member 1 (CYP11A1), CYP17A1, 3β-hydroxysteroid dehydrogenase isoenzyme-1 (HSD3B1), or 17β-hydroxysteroid dehydrogenase (HSD17B), is correlated with poor survival of BC patients [4,15].