Hormone Action and Clinical Significance of the Estrogen Receptor #x03B1;.- Role of ER#x03B2; in Clinical Breast Cancer.- Hormone Action and Breast Cancer.- Estrogen Receptors in Breast Tumors of African American Patients.- BRCA1 Cross-Talk with Hormone Receptors.- Metastasis of Hormone Receptor Positive Breast Cancer.- Endocrine Therapy with Selective Estrogen Receptor Modulators (SERMs) and Aromatase Inhibitors in the Prevention and Adjuvant Therapy Settings.- Biomarkers in Neoadjuvant Trials.- Hormone Resistance.- Strategies of Hormonal Prevention.- Estrogen Receptor Phenotypes Defined by Gene Expression Profiling.