Systemic Therapy for Women with ErbB2-Positive Breast Cancer: New Options, New Challenges.

摘要

Advances in understanding the biology of breast cancer have led to the classification of tumors based upon their molecular features. With the advent of targeted therapies for both early and metastatic breast cancer (MBC), treatments are increasingly tailored towards the underlying individual tumor biology. Endocrine therapy for hormone receptor(HR)-positive tumors as well as compounds directed towards the inhibition of the ErbB2 (HER2) receptor are the two main advances in targeted therapy for women presenting with breast cancer, and have led to great strides in the understanding and treatment of this heterogeneous tumor entity. ErbB2 is a trans-membrane receptor with tyrosine kinase activity, and is the most important growth factor within a family of related proteins in breast cancer. The ErbB group is composed of the 4 members ErbBl, ErbB2, ErbB3, and ErbB4. Activation of the ErbB autocrine growth pathway is a common mechanism for autonomous, dysregulated tumor cell proliferation and differentiation as well as angiogenesis, invasion, metastasis, and inhibition of apoptosis in the majority of human epithelial cancers. Dysfunctional ErbB2 signaling networks are reportedly present in a cohort of breast carcinomas with poor prognosis. In this respect, the ErbB2 pathway has become an attractive therapeutic target.