| Bioactivity | 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[1][2][3]. 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[5]. Tamoxifen activates autophagy and induces apoptosis[4]. Tamoxifen also can induce gene knockout of CreER(T2) transgenic mouse[6]. |
| Invitro | Tamoxifen (ICI 47699) shows strong inhibition of MCF-7 cells (EC50=1.41 μM) and to a lesser extent the T47D cells (EC50=2.5 μM) but does not affect the MDA-MB-231 cells[2]. |
| In Vivo | Injection of pre-mutant mice with Tamoxifen (75 mg/kg; injected for 5 days at 6 weeks of age) results in the excision of the floxed exon and, thus, in a gene knockout[3]. Animal Model: |
| Name | Tamoxifen |
| CAS | 10540-29-1 |
| Formula | C26H29NO |
| Molar Mass | 371.51 |
| Appearance | Solid |
| Transport | Room temperature in continental US; may vary elsewhere. |
| Storage | 4°C, protect from light *In solvent : -80°C, 6 months; -20°C, 1 month (protect from light) |
| Reference | [1]. Osborne CK. Tamoxifen in the treatment of breast cancer. N Engl J Med. 1998 Nov 26;339(22):1609-18. [2]. Hawariah A, et al. In vitro response of human breast cancer cell lines to the growth-inhibitory effects of styrylpyrone derivative (SPD) and assessment of its antiestrogenicity. Anticancer Res. 1998 Nov-Dec;18(6A):4383-6. [3]. Jun Nagai, et al. Hyperactivity with Disrupted Attention by Activation of an Astrocyte Synaptogenic Cue. Cell. 2019 May 16;177(5):1280-1292.e20. [4]. Zhao R, et al. Tamoxifen enhances the Hsp90 molecular chaperone ATPase activity. PLoS One. 2010 Apr 1;5(4):e9934. [5]. Kedjouar B, et al. Molecular characterization of the microsomal tamoxifen binding site. J Biol Chem. 2004 Aug 6;279(32):34048-61. [6]. Feil S, et, al. Inducible Cre mice. Methods Mol Biol. 2009;530:343-63. [7]. Laura Cooper, et al. Screening and Reverse-Engineering of Estrogen Receptor Ligands as Potent Pan-Filovirus Inhibitors. J Med Chem. 2020 Sep 4. |