Östrogenrezeptor-β-Isoformen -Funktionen und klinische Bedeutung bei Brustkrebs

Zusammenfassung

Östrogenrezeptoren (ER) sind ligandenregulierte Transkriptionsfaktoren, die eine zelluläre Reaktion auf Östrogene vermitteln. Bisher konnten die zwei ER-Typen ERα und ERβ identifiziert werden. ERα besitzt eine wesentliche Bedeutung als prädiktiver Faktor für die Wirksamkeit einer endokrinen Therapie des Mammakarzinoms. Patientinnen, deren Tumoren ERα exprimieren, erhalten eine adjuvante endokrine Therapie. Neuere Untersuchungen liefern Hinweise für eine entscheidende Bedeutung von ERβ und seinen Isoformen für die Prognose von Brustkrebserkrankungen. In dieser Übersicht wird der aktuelle Kenntnisstand zur Funktion von ERβ und seinen Subtypen zusammengefasst.

Abstract

Estrogen receptors (ER) are hormone regulated transcription factors which mediate the cellular estrogen response. So far two types of ER could be identified, ERα and ERβ. ERα plays an important role as a predictive factor for the effectiveness of endocrine agents in the treatment of breast cancer. Patients with ERα positive tumors receive adjuvant endocrine therapy. Recent findings indicate a crucial role of ERβ and its isoforms for the prognosis of breast cancer. This paper reviews the current knowledge on the functions of ERβ and its splice variants.

Schlüsselwörter

Östrogenrezeptoren - Östrogenrezeptor β - Mammakarzinom - Tamoxifenresistenz

Key words

estrogen receptors - estrogen receptor β - breast cancer - tamoxifen resistance

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