OBHS is an estrogen receptor α (ERα) inhibitor. OBHS can also be used as a blowing agent[1][2].
Giredestrant tartrate (GDC-9545 tartrate), a non-steroidal ER ligand, is an orally active and selective estrogen receptor (ER) antagonist. Giredestrant tartrate potently competes with estradiol for binding and induces a conformational change within the ER ligand binding domain. Anti-tumor activity[1].
Tamoxifen-d3 is the deuterium labeled Tamoxifen[1]. Tamoxifen (ICI 47699) is an orally active, selective estrogen receptor modulator (SERM) which blocks estrogen action in breast cells and can activate estrogen activity in other cells, such as bone, liver, and uterine cells[2][3][4]. Tamoxifen is a potent Hsp90 activator and enhances the Hsp90 molecular chaperone ATPase activity. Tamoxifen also potent inhibits infectious EBOV Zaire and Marburg (MARV) with IC50 of 0.1 μM and 1.8 μM, respectively[6]. Tamoxifen activates autophagy and induces apoptosis[5]. Tamoxifen also can induce gene knockout of CreER(T2) transgenic mouse[7].
PAC comprises an antibody conjugated via a linker to a PROTAC. PAC extracts from patent WO2017201449A1, compound PAC1. PAC is a more marked estrogen receptor-alpha (ERα) degrader compared to PROTAC (without Ab).
ERB-196 is a nonsteroidal selective estrogen receptor-β (ERβ) agonist.
ERD-3111 (Compound 44) is an orally active PROTAC ERα degrader (DC50: 0.5 nM). ERD-3111 inhibits tumor growth in the parental MCF-7 xenograft model with wild-type ER and two clinically relevant ESR1 mutated mice model. ERD-3111 can be used in the research of ER+ breast cancer[1].
ERD-308 is a highly potent PROTAC degrader of estrogen receptor (ER), with an DC50 of 0.17 nM in MCF-7 cells[1].
Estrogen receptor modulator 10 (compound G-5b) is an Estrogen receptor (ER) antagonist (IC50=6.7 nM) and degrader (DC50=0.4 nM). Estrogen receptor modulator 10 can induce apoptosis. Estrogen receptor modulator 10 can block cells at the G1/G0 phase. Estrogen receptor modulator 10 can be used in cancer studies[1].
Ospemifene is a selective estrogen for the prevention of postmenopausal osteoporosis with IC50 values of 827nM and 1633nM for ERα and ERβ, respectively. target: ERα and ERβIC50:827 and 1633 nm for ERα and -β, respectively[1] IN vitro: The estrogen-dependent MCF-7 human breast cancer cells were used as a model for studies on the effects of Ospemifene on breast cancer cells. The addition of the compound at concentrations of 0.1 nm to 10 μm did not cause a significant increase in MCF-7 cell growth in vitro when studied by measuring ATP or 3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide levels, cell numbers, and rate of [3H]thymidine incorporation during a 7-day culture period. On the other hand, the compound did not inhibit the growth stimulation caused by 1 nm estradiol, except at a concentration 10 mm by only 30%. Similar results were obtained with ZR 75–1 cells, another estrogen-dependent human breast cancer cell line. The cytotoxicity of FC1271a at high concentrations was therefore markedly lower than that for TAM, TOR, or RAL.[1]In ER+ MCF-7 cells, TOR VI and FC-1271a exhibited anti-estrogenic activity. The anti-estrogenic effects of these compounds were less potent as anti-estrogens when compared with TOR and RAL.[2]"In vivo: In the DMBA rat mammary carcinoma model, Ospemifene showed a clear antitumor effect that seemed to be caused primarily by a decrease in the appearance of new tumors but also by a retardation of tumor progression without stimulating the growth of human breast cancer cells.[1]Tumor growth was shown to be inhibited at these doses, indicating anti-estrogenic activity at all doses including 50 and 100 mg/kg Ospemifene. By the end of treatment, MCF-7 tumors in Ospemifene treated mice were statistically smaller compared with control tumors.[2]
27-Hydroxycholesterol is a selective estrogen receptor modulator and an agonist of the liver X receptor.
SLU-PP-1072 is a dual ERRα/γ inverse agonist, used in Prostate cancer (PCa) research. SLU-PP-1072 disrupts PCa cell metabolism, and induces apoptosis via dysregulating cell cycle[1].
Dehydrodiconiferyl alcohol is an estrogen receptor agonist that can promote BMP-2-induced osteoblastogenesis. Dehydrodiconiferyl alcohol also exerts anti-inflammatory activity through inactivation of NF-κB pathways[1][2].
GNE-274 is a non-degrader that is structurally related to GDC-0927 (ER degrader). GNE-274 does not induce ER turnover and functions as a partial ER agonist in breast cancer cell lines. GNE-274 increase chromatin accessibility at ER-DNA binding sites, while GDC-0927 do not. GNE-274 is a potent inhibitor of ER-ligand binding domain (LBD). GNE-274 can be used for cancer research[1][2].
Enclomiphene ((E)-Clomiphene) is a potent and orally active non-steroidal estrogen receptor antagonist, with antioestrogenic property. Enclomiphene can be used for the research of ovarian dysfunction, testosterone deficiency, male hypogonadism and type 2 diabetes[1].
Estrogen receptor-IN-1 (compound 16) is a potent estrogen receptor (ER) inhibitor with IC50s of 13, 5µM for ERα and Erβ, respectively[1].
Kaempferol inhibits estrogen receptor α expression in breast cancer cells and induces apoptosis in glioblastoma cells and lung cancer cells by activation of MEK-MAPK.
ERRγ agonist-2 is a potent and selective ERRγ inverse agonist with a Kd value of 6.5 μM. ERRγ agonist-2 inhibits the expression of hepcidin, fibrinogen and gluconeogenic genes. ERRγ agonist-2 has antimicrobial, anti-coagulant and antidiabetic activities[1].
Coumestrol, a phytoestrogen present in soybean products, exhibits activities against cancers, neurological disorders, and autoimmune diseases. It suppresses proliferation of ES2 cells with an IC50 of 50 μM.
7β-Hydroxy-epi-androsterone (7β-Hydroxy-EpiA) can bind to ERβ and has anti-inflammatory and neuroprotective properties. 7β-Hydroxy-epi-androsterone is an endogenous androgenic derivative of dehydroepiandrosterone[1][2][3].
Estradiol benzoate is a synthetic ester, is the first form of estrogen to be marketed.
(±)-Equol is the racemate of equol. Equol is a metabolite of the soy isoflavones, daidzin and daidzein.
RU58668 is a steroidal antiestrogen that can be used as a potent antiproliferative agent on MCF-7 cells. RU58668 has the potential for the breast cancer research[1].
TPBM is a potent estrogen receptor α (ERα) inhibitor with an IC50 value of 9 μM for 17β-estradiol (E2)-ERα. TPBM reduces E2·ERα recruitment to an endogenous estrogen-responsive gene. TPBM inhibits E2-dependent growth of ERα-positive cancer cells (IC50=5 μM). TPBM is not toxic to cells and does not affect estrogen-independent cell growth[1].
Tibolone is a broad spectrum gonadal steroid agonist with progestagenic, androgenic, and estrogenic activities. Tibolone can be used for postmenopausal osteoporosis research[1][2].
GDC-0927 Racemate (SRN-927 Racemate) is a degrader of estrogen receptor, potently inhibits ER-α activity, with an IC50 of 0.2 nM, and is used in the research of ER-related diseases.
Acolbifene (EM652) is a fourth-generation selective estrogen receptor antagonist with a LC50 value of 22±3 nM.
Zuclomiphene citrate is a cis isomer of Clomiphene citrate. Zuclomiphene citrate has an antiestrogenic effect and can inhibit the secretion of luteinizing hormone (LH) more than the trans isomer. Zuclomiphene citrate is also an orally active hypocholesterolemic agent[1][2][3][4].
Mestranol is the 3-methyl ether of ethinylestradiol. It was the estrogen used in many of the first oral contraceptives.Target: Estrogen Receptor/ERRMestranol is absorbed very rapidly from the digestive tract and maximum plasma levels are attained in 1-4 hours, the majority at 1-2 hours. Detectable levels of mestranol are present 24 hours postingestion in 58% of subjects after a 50 μg dose and in 79% after a 100 μg dose. At all dose levels, highest plasma mestranol levels and area under the curve of plasma levels (AUC) occurred in Sri Lankan women, and lowest plasma levels in Nigerian women, even when corrected for body surface differences [1].
2-Hydroxyestrone (Catecholestrone) is a specific receptor-mediated antiestrogenic agent. 2-Hydroxyestrone is anticarcinogenic[1][2].
Zearalenone is a mycotoxin produced mainly by fungi belonging to the genus Fusarium in foods and feeds. Possess oestrogenic activity in pigs, cattle and sheep, with low acute toxicity. Causes precocious development of mammae and other estrogenic effects in young gilts[1][2].