Similarly, Borengassar et al. studied the regulation of NF-1 on the expression of Sulfotransferase isoform 1A1 (SULT1A1) gene in breast cancer in vitro, and found that NF1A, NF1B and NF1C can down-regulate the expression of SULT1A1 [79]. The gene discussed is NF1; the disease is breast carcinoma.