title: Estrogen receptors in breast and bone: from virtue of remodeling to vileness of metastasis.
abstract: Bone metastasis is a prominent cause of morbidity and mortality in cancer. High rates of bone colonization in breast cancer, especially in the subtype expressing estrogen receptors (ERs), suggest tissue-specific proclivities for metastatic tumor formation. The mechanisms behind this subtype-specific organ-tropism remains largely elusive. Interestingly, as the major driver of ER+ breast cancer, ERs also have important roles in bone development and homeostasis. Thus, any agents targeting ER will also inevitably affect the microenvironment, which involves the osteoblasts and osteoclasts. Yet, how such microenvironmental effects are integrated with direct therapeutic responses of cancer cells remain poorly understood. Recent findings on ER mutations, especially their enrichment in bone metastasis, raised even more provocative questions on the role of ER in cancer-bone interaction. In this review, we evaluate the importance of ERs in bone metastasis and discuss new avenues of investigation for bone metastasis treatment based on current knowledge.
authors.affiliation: Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA.|Dan L Duncan Cancer Center, Houston, TX, USA.|Department of Molecular and Cellular Biology, Houston, TX, USA.
authors.forename: I
authors.initials: I
authors.lastname: Bado
authors.affiliation: Department of Orthopaedic Surgery and Rehabilitation, University of Texas Medical Branch, Galveston, TX, USA.
authors.forename: Z
authors.initials: Z
authors.lastname: Gugala
authors.affiliation: Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA.|Dan L Duncan Cancer Center, Houston, TX, USA.
authors.forename: S A W
authors.initials: SAW
authors.lastname: Fuqua
authors.affiliation: Lester and Sue Smith Breast Center, Baylor College of Medicine, Houston, TX, USA.|Dan L Duncan Cancer Center, Houston, TX, USA.|Department of Molecular and Cellular Biology, Houston, TX, USA.|McNair Medical Institute, Baylor College of Medicine, Houston, TX, USA.
authors.forename: X H-F
authors.initials: XH
authors.lastname: Zhang
mesh_terms: D001846:Bone Development; D001859:Bone Neoplasms / Q000378:metabolism* / Q000556:secondary*; D016723:Bone Remodeling; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology*; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000235:genetics / Q000378:metabolism*; D005260:Female; D006801:Humans; D010006:Osteoblasts / Q000378:metabolism; D010010:Osteoclasts / Q000378:metabolism; D017154:Stromal Cells / Q000378:metabolism; D059016:Tumor Microenvironment / Q000276:immunology
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta