HSD17B1 and seminoma: In a comparison of expression levels of the sex hormone-related genes between NSGCT and seminoma, the POMC gene coding for an essential regulator of steroid biosynthesis, and genes involved in metabolism (HSD17B1, HSD17B2, SRD5A1) and transport of sex hormones (SHBG) were significantly upregulated in NSGCT in both the TCGA and GSE99420 cohorts.