Тамоксифен цитрат

Описание

Tamoxifen is a non-steroidal compound with structural similarities to diethylstilbestrol. Tamoxifen citrate is an estrogen receptor antagonist/partial agonist. Induces oxidative stress and apoptosis in estrogen receptor-negative cancer cell lines. Displays neuroprotective effects in permanent focal ischemia. Inhibits PKC. Potent agonist at GPR30 (membrane estrogen receptor). Clinically useful breast cancer agent.

Химические свойства

Tamoxifen citrate is a white to off-white powder with no smell. It can dissolve in methanol, ethanol, and acetone to varying degrees and can slightly dissolve in trichloromethane, but it is almost insoluble in water. It can dissolve in glacial acetic acid. When tamoxifen citrate reaches a temperature between 142-148°C, it melts and decomposes at the same time.

Использование

Tamoxifen Citrate is a selective estrogen response modifier (SERM), protein kinase C inhibitor and anti-angiogenetic factor. Tamoxifen is a prodrug that is metabolized to active metabolites 4-hydroxytamoxifen (4-OHT) and endoxifen by cytochrome P450 isoforms CYP2D6 and CYP3A4.

Общее описание

Tamoxifen, 2-[4-(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethylethanamine(Nolvadex), is a triphenylethylene SERM used to treatearly and advanced breast carcinoma in postmenopausalwomen. Tamoxifen is used as adjuvant treatment for breastcancer in women following mastectomy and breast irradiation.It reduces the occurrence of contralateral breast cancerin patients receiving adjuvant tamoxifen therapy. It is alsoeffective in the treatment of metastatic breast cancer in bothwomen and men. In premenopausal women with metastaticbreast cancer, tamoxifen is an alternative to oophorectomyor ovarian irradiation. Tamoxifen can be used preventativelyto reduce the incidence of breast cancer in women athigh risk. Antiestrogenic and estrogenic side effects caninclude hot flashes, nausea, vomiting, platelet reduction,and (in patients with bone metastases) hypercalcemia. Likeall triphenylethylene derivatives, it should be protectedfrom light.

Биологическая активность

Estrogen receptor antagonist/partial agonist. Selective and potent inhibitor of mammalian sterol isomerase. Neuroprotective in female rats in vivo . Also high affinity agonist at the membrane estrogen receptor GPR30.

Профиль безопасности

Confirmed human carcinogen with experimental carcinogenic data. Poison by intraperitoneal route. Moderately toxic by ingestion. Experimental reproductive effects. Human systemic effects: visual field changes, retinal changes. An anti-estrogenic drug. Mutation data reported. When heated to decomposition it emits toxic fumes of NOx.

Метаболизм

The major metabolite of tamoxifen is N-desmethyltamoxifen,which reaches steady-state levels higher than tamoxifenitself. It is believed that N-desmethyltamoxifen contributessignificantly to the overall antiestrogenic effect. Anothermetabolite, 4-hydroxytamoxifen, is a more potent antiestrogenthan tamoxifen, but because it is only a minor metaboliteof tamoxifen, it probably does not contribute significantly tothe therapeutic effects. 4-Hydroxytamoxifen, with its greateraffinity for the ERs, however, has been used extensively inpharmacological studies of these receptors. Tamoxifen concentrationsare reduced if coadministered with rifampin, a cytochromeP450 inducer.