Methods and compositions are provided for treatment of disorders associated with aberrant adrenal cortex cell behavior, including (but not limited to) treatment of adrenocortical carcinoma (ACC), Cushing's syndrome and/or pituitary ACTH excess (Cushing's Disease). Such methods involve administration of an effective amount N-(2,6-bis(1-methylethyl)phenyl)-N′-((1-(4-(dimethylamino)phenyl)cyclopentyl)-methyl)urea hydrochloride to the patient.