The down-regulated genes in multinodular goiter were related to several molecular pathways, especially phospholipase C (PLCD4), apoptosis pathways (TNFRSF19), heat shock proteins (HSPA1A, HSPA6), growth factors (SHC3, NRG1), p53 proto-oncogene pathways (THBS1), and chaperone cell repair pathways (BAG3); on the other hand, the inflammatory (COL14A) and complement system (C4B) pathways were up-regulated in multinodular goiter tissue, in addition to the exclusive presence of an antisense transcription from the H19 locus, which encodes the nucleolar protein HOTS in multinodular goiter [35]. Here, NRG1 is linked to multinodular goiter.