Hormono-biological therapy in metastatic breast cancer: preclinical evidence, clinical studies and future directions.
Breast cancer growth is regulated by coordinated actions of the estrogen receptor (ER) and various growth factor receptor signalling pathways. This complex interactive signalling potentially explains some of the reasons behind endocrine therapy action and resistance. Recent research into the molecular biology of ER signalling has revealed new molecular targets which, if present in cancer cells, might be additionally targeted using various signal transduction inhibitors to overcome or prevent resistance to endocrine therapy. The dynamic inverse relationship between the expression of ER and growth factor receptors brings more excitement to the potential of restoring ER expression in apparently ER-negative cells by inhibition of growth factor signalling. The multiple pathways involved in activating ERs also provide a rationale for combining endocrine and non-endocrine therapies that block different signalling pathways. Ongoing clinical trials promise to further improve the present care for breast cancer patients.
Tonini
Giuseppe
G
University Campus Bio-Medico, Medical Oncology, Via Emilio Longoni, 83 00155 Rome, Italy. g.tonini@unicampus.it
Schiavon
Gaia
G
Fratto
Maria Elisabetta
ME
Vincenzi
Bruno
B
Santini
Daniele
D
D000818:Animals; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy*; D019008:Drug Resistance, Neoplasm; D005260:Female; D006801:Humans; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy*; D020239:Receptor Cross-Talk / Q000502:physiology; D015398:Signal Transduction / Q000187:drug effects*
D018931:Antineoplastic Agents, Hormonal