GCS the basic enzyme in the GSL-biosynthesis pathway (Figure 1A) is overexpressed in multiple human cancers including hepatocellular carcinoma, breast, cervix, non-small-cell lung cancer, and papillary thyroid carcinoma [8,19,20,21], and also in many cancer cell lines [22]. The gene discussed is UGCG; the disease is thyroid gland papillary carcinoma.