4-Hydroxytamoxifen Ready Made Solution

5 mg/mL in ethanol: isopropanol (95:5)

4-OHT, cis/trans-4-Hydroxytamoxifen
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:

Quality Level

biological source





5 mg/mL in ethanol: isopropanol (95:5)

shipped in

dry ice

storage temp.




InChI key


Biochem/physiol Actions

Trans isoform of 4-hydroxytamoxifen possesses antiestrogenic activity, while the cis 4-hydroxytamoxifen serves as a key agonist for estrogen receptor. 4-Hydroxytamoxifen promotes apoptosis via activation of p38 pathway in breast cancer cell cultures.
4-Hydroxytamoxifen is an active metabolite of Tamoxifen. 4-Hydroxytamoxifen is formed by cytochrome P450 2D6 in human liver and is a potent and selective estrogen receptor antagonist. 4-Hydroxytamoxifen has been used to stimulate LC3 lipidation and to form autophagic vesicles in a superoxide-dependent manner. Tamoxifen and 4-Hydroxytamoxifen markedly induce cytochrome P450 3A4 (a major drug-metabolizing enzyme) in primary cultures of human hepatocytes. 4-Hydroxytamoxifen undergoes a cis-trans (E-Z) isomerization, a process that occurs in all common laboratory solvents.

Preparation Note

4-Hydroxytamoxifen is provided in a 13 mM solution. The recommended working concentration is 10-100 μM. Therefore, 4-Hydroxytamoxifen Ready Made Solution should be diluted 1:130 - 1:1,300 in cell culture media.

Signal Word



UN1170 - class 3 - PG 2 - Ethanol, solution

WGK Germany


Flash Point(F)

57.2 °F

Flash Point(C)

14 °C

Certificate of Analysis

Certificate of Origin

Activation of the p38 mitogen-activated protein kinase pathway by estrogen or by 4-hydroxytamoxifen is coupled to estrogen receptor-induced apoptosis.
Zhang C C and Shapiro D J
The Journal of Biological Chemistry, 275(1), 479-486 (2000)
Characterization of tamoxifen and 4-hydroxytamoxifen glucuronidation by human UGT1A4 variants.
Sun D, et al.
Breast Cancer Research, 8(4), R50-R50 (2006)
Izumi Kaji et al.
Gastroenterology, 159(4), 1390-1405 (2020-06-15)
Myosin VB (MYO5B) is an essential trafficking protein for membrane recycling in gastrointestinal epithelial cells. The inactivating mutations of MYO5B cause the congenital diarrheal disease, microvillus inclusion disease (MVID). MYO5B deficiency in mice causes mislocalization of SGLT1 and NHE3, but...
Martina Damo et al.
Nature biotechnology, 39(1), 64-73 (2020-07-29)
Inducible expression of neoantigens in mice would enable the study of endogenous antigen-specific naïve T cell responses in disease and infection, but has been difficult to generate because leaky antigen expression in the thymus results in central T cell tolerance....
Eleonora Grisard et al.
EBioMedicine, 46, 79-93 (2019-07-16)
Metastatic colorectal cancer (CRC) remains a deadly disease. Identifying locally advanced CRC patients with high risk of developing metastasis and improving outcome of metastatic CRC patients require discovering master regulators of metastasis. In this context, the non-coding part of the...

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