Therapeutic Targeting of Amyloid Precursor Protein and its Processing Enzymes for Breast Cancer Treatment.

Breast cancer cases in women are increasing at an alarming rate globally and extensive research is being conducted to identify a breakthrough medicine against this dreadful disease. In fact, researchers are looking for fresh targets to develop novel treatment strategies for cancer of the breasts. In this article, 'amyloid precursor protein' or (APP) and its processing enzymes are deeply studied so as to explore the same as prospective targets for breast cancer treatment. Even though most of the studies on APP and its processing enzymes have been performed on neuronal cells owing to their linkage with Alzheimer's disease, they are omnipresent on various non-neuronal cells also. Interestingly, APP and its processing enzymes have a role in the proliferation of cancer cells as well as in their growth, adherence and movement. Over-synthesis of APP and its processing enzymes are emerging as important hallmark features in breast cancer. It has been found that APP and its processing enzymes, i.e., γ-secretase and α- secretase are strongly linked with breast cancer via Akt phosporylation and Notch signaling pathways. Thus, targeting APP or γ-secretase or α-secretase could be considered as an effective strategy to treat breast cancer and even metastasis. There are various clinical trials which are in progress to explore the potential of γ-secretase inhibitor against breast cancer. Hence, the present review is composed of two sections, one section deals with all the possible linkages of APP and APP processing enzymes (α- secretase, β-secretase and γ-secretase) with breast cancer. However, the other section provides recent information on breast cancer treatment strategy using APP and APP processing enzymes as targets. We strongly believe that compilation of these studies would be beneficial to the scientist working in the field of 'breast cancer-treatment'.