Molecular basis and possibilities for modulation of resistance to anti-HER2 therapy

In breast cancer, targeted therapy is becoming increasingly important. Next to the oldest targeted therapy in breast cancer, i.e. endocrine therapy, two novel targeted agents are already approved for use in HER2 positive breast cancer: the monoclonal antibody trastuzumab (Herceptin®) is approved for adjuvant therapy as well as for metastatic disease (MBC). The small molecule lapatinib (Tyverb®) can be used in MBC if progression on/after trastuzumab occurs (AGO guidelines 2008). With more and more patients being treated by these agents, treatment failure of anti-HER2 therapies has become a clinically relevant iss…