AP23573, also known as ridaforolimus, is primarily used in the field of oncology. It is an mTOR inhibitor, which targets the mTOR pathway involved in cell growth and proliferation. This makes it effective in treating certain types of cancers by inhibiting tumor growth. It has been studied in clinical trials for its potential in managing sarcomas and other solid tumors. Additionally, it is being explored for its role in combination therapies, where it enhances the efficacy of other anticancer drugs. Its application extends to research settings, where it is used to study the mTOR signaling pathway and its implications in cancer biology.