NR1H4 and malignant colon neoplasm: To determine whether FXR plays a role in controlling proliferation of human colon cancer cells, we examined the actions of increasing concentrations of a selective FXR antagonist, guggulsterone (Z form), and agonist, GW4064, on proliferation of three commonly-used human cancer cell lines, H508, SNU-C4 and HT-29.