Selective estrogen response modifiers

The dimerization of ER can involve either homo- or heterodimers—(ER-a)2, (ER-/8)2, or ER-a/ ER-y8—thus expanding the physiological specificity and action of estrogen in the target tissue. Breast tumors that contain ER are treated with selective estrogen response modifiers (SERMs). Current assays for ER in breast tumors only identify ER-a, but ER-a- negative, ER- 8- positive tumors may also respond to SERM therapy. 

H 6278 4-Hydroxytamoxifen, minimum 70% of Z-isomer (remainder primarily E-isomer) Metabolism of tamoxifen, which is a potent selective estrogen response modifier (SERM) the trans (Z) isom has efficacy against estrogen-sensitive cancers. The cis (E) isomer is an estrogen agonist. 

R 1402 Raloxifene hydrochloride Selective estrogen response modifier (SERM), may be effective against estrogen-sensitive cancers. 

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