Table 1.

EC₅₀ concentrations and relative androgenic potencies (RAP) of compounds in the yeast androgen biosensor expressing yeast enhanced green fluorescent protein in response to androgens

Compound	Qualitative response for AR agonisma	Commentsb	EC50 (nM) in the yeast androgen bioassayc	RAPd
17β-Testosterone	Positive (11/11)	Strong AR agonist	76	1.0
5α-Dihydrotestosterone	Positive (21/21)	Strong AR agonist, weak ER agonist	33	2.3
17β-Boldenone			510	0.15
17β-Trenbolone	Positive	Binds strongly to AR	52	1.5
Methyltrienolone	Positive (8/8)	AR agonist	54	1.4
Tetrahydrogestrinone		AR agonist	65	1.2
17β-Estradiol	Positive (10/11)	AR agonist and antagonist, strong ER agonist	9,000	0.0084
Estrone	Positive (2/2)	AR agonist, strong ER agonist	NR	NR
17α-Estradiol	Negative (1/1)	ER agonist	NR	NR
17α-Ethynylestradiol	Negative (1/1)	Strong ER agonist	NR	NR
Diethylstilbestrol	Negative (2/2)	Strong ER agonist	NR	NR
4-Hydroxytamoxifene	Negative (1/1)	ER antagonist	NR	NR
Progesteronef	Positive (7/9)		1,700	0.045
Medroxyprogesterone acetate	Positive (4/4)	Weak AR agonist	1,500	0.051
Corticosterone	Negative (1/1)	Binds weakly to AR	NR	NR
Dexamethasone	Positive (3/4)	AR agonist	NR	NR
Flutamide	Negative (5/5)	AR antagonist	NR	NR
2,4,6-Tribromophenol			NR	NR
BDE-19			NR	NR
4-OH-BDE-17			NR	NR

AR androgen receptor, ER estrogen receptor, NR no response

^aQualitative response for AR agonism across all mammalian cell reporter gene studies (data obtained from [27])

^bComments obtained from [27]

^cThe EC₅₀ is the concentration giving half-maximum response.

^dThe RAP is defined as the ratio between the EC₅₀ of 17β-testosterone and the EC₅₀ of the compound.

^eThis compound was toxic to yeast above 30 μM.

^fThese compounds reach a maximum response that is lower than 70% of the maximum response obtained with 17β-testosterone. The maxima obtained with 4-androstenedione and progesterone are about 40 and 35%, respectively.