Tamoxifen is an orally active selective estrogen receptor modulator (SERM) that acts as an estrogen antagonist in breast cells and an agonist in bone, liver, and uterine cells. It can be used to induce gene knockout and liver injury models in mice, and also exhibits multiple biological activities, including activation of Hsp90, induction of autophagy and apoptosis, and inhibition of EBOV and MARV viral infections.

DU-145 cells:10.87 μM, CHO cells:> 100 μM, A-431 cells:> 100 μM, A549 cells:1.86 μg/mL, 518A2 cells:7.62 μM, B16-F10 cells:64.87 μM, DLD-1 cells:11.06 μM, A2780 cells:7.77 μM, A2058 cells:12.5 μM (EC50), Astrocyte:> 10 μM, FaDu cells:5.39 μM, A253 cells:8.92 μM

METHODS: Human breast cancer cells MCF-7 were treated with Tamoxifen (0.25-4 μM) for 24 h. Cell viability was measured using the CCK-8.
RESULTS: Tamoxifen significantly inhibited the proliferation of MCF-7 cells in a dose-dependent manner. [1]
METHODS: ER-negative breast cancer cells SK-BR3, MDA-MB-453, MDA-MB-468, MDA-MB-231, and HCC-1937 were treated with Tamoxifen (1-10 μM) for 24-36 h, and apoptosis was detected using Flow Cytometry.
RESULTS: Tamoxifen induced apoptosis in MDA-MB-231, MDA-MB-468, MDA-MB-453 and SK-BR3 cells in a dose- and time-dependent manner, while no significant apoptotic effect was observed in HCC-1937 cells. [2]

METHODS: To test the antitumor activity in vivo, Tamoxifen (100 mg/kg) was administered orally to NCr athymic nude mice bearing ER-negative breast cancer tumors MDA-MB-468 or HCC-1937 three times per week for four to five weeks.
RESULTS: Tamoxifen significantly inhibited the growth of MDA-MB-468 tumors, whereas the growth of HCC-1937 tumors was not affected. [2]
METHODS: To test the effect on mouse behavior, Tamoxifen (75 mg/kg in 10% ethanol+90% sunflower seed oil) was administered intraperitoneally to C57BL/6 mice once a day for seven days.
RESULTS: Tamoxifen affects motor activity, socialization, and anxiety in mice. [3]