Present and Emerging Targeted Therapy for Metastatic Breast Cancer
Keywords:Breast cancer, targeted therapy, EGFR, HER2, VEGF, mTOR inhibitors, PARP-1 inhibitors.
Breast carcinoma is a complex and heterogeneous disease and several different molecular alterations are involved in its pathogenesis and progression. Different growth factor receptor-driven signaling pathways sustain the growth and survival of breast cancer cells. Actually, three targeted agents are available for the treatment of breast cancer: trastuzumab, a monoclonal antibody directed against the human epidermal growth factor receptor-2 (HER2); lapatinib, an oral available dual tyrosine-kinase inhibitor of the human epidermal growth factor receptor-1 (HER1, EGFR) and HER2; bevacizumab, a monoclonal antibody directed against the vascular endothelial growth factor (VEGF). All these agents demonstrated to be synergistic with chemotherapy. In addition, recently concluded clinical trials suggest that signaling inhibitors can prevent or overcome resistance to endocrine therapy in estrogen receptor positive (ER+) breast cancer. Moreover, several other targeted drugs are under investigation in clinical trials. The aim of this review is to give a synthetic but complete picture of various targeted agents for breast cancer therapy that are under clinical trials or currently available in clinical practice.
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