title: Mechanisms of action of endocrine treatment in breast cancer.
abstract: Endocrine treatment plays an important role in the therapy of breast cancer. While the basic mechanisms are understood, additional mechanisms may be of importance to their action and they may also contribute to the mechanism(s) of acquired resistance. Currently, several novel drugs are entering into clinical trials. Observations of the absence or presence of cross resistance to novel 'pure' steroidal antiestrogens and the non-steroidal tamoxifen may add important information to our understanding of the mechanisms of action of both classes of drugs. Similarly, exploration of different aromatase inhibitors in sequence or concert, as well as the combining of different endocrine treatment options may be warranted. Additionally, alterations in different biochemical parameters such as growth factors should not only be carefully explored in relation to treatment options but should also be followed during the course of treatment to asess alterations over time and in relation to the development of drug resistance.
authors.affiliation: Department of Oncology, Haukeland University Hospital, Bergen, Norway.
authors.forename: E
authors.initials: E
authors.lastname: Lønning
authors.forename: E A
authors.initials: EA
authors.lastname: Lien
mesh_terms: D000302:Adrenal Cortex / Q000187:drug effects / Q000503:physiopathology; D000328:Adult; D000368:Aged; D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000145:classification / Q000494:pharmacology* / Q000627:therapeutic use; D047072:Aromatase Inhibitors; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000503:physiopathology / Q000628:therapy; D017024:Chemotherapy, Adjuvant; D003131:Combined Modality Therapy; D018432:Drug Resistance, Multiple; D004791:Enzyme Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D004965:Estrogen Antagonists / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D004967:Estrogens / Q000097:blood / Q000502:physiology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000037:antagonists & inhibitors / Q000502:physiology; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy / Q000503:physiopathology; D008593:Menopause; D051379:Mice; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology / Q000628:therapy; D011374:Progesterone / Q000037:antagonists & inhibitors / Q000502:physiology; D011372:Progestins / Q000037:antagonists & inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D011960:Receptors, Estrogen / Q000187:drug effects / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects; D013256:Steroids / Q000378:metabolism; D013629:Tamoxifen / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004791:Enzyme Inhibitors; D004965:Estrogen Antagonists; D004967:Estrogens; D009363:Neoplasm Proteins; D011372:Progestins; D011960:Receptors, Estrogen; D013256:Steroids; D013629:Tamoxifen; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D007334:Insulin-Like Growth Factor I