NR3C1 and carcinoid tumor: The glucocorticoid receptor (GR) antagonist mifepristone, a non-selective steroidal GR antagonist with progesterone receptor activity, has been shown to reverse the inhibitory effects of glucocorticoids on SSTR2 mRNA expression in the human neuroendocrine cell lines BON (carcinoid) and TT (medullary thyroid carcinoma) (27).