Retaspimycin is primarily investigated for its potential in cancer therapy, particularly as an inhibitor of heat shock protein 90 (Hsp90). By targeting Hsp90, it disrupts the stability and function of client proteins that are crucial for cancer cell survival and proliferation. This makes it a promising candidate for treating various cancers, including non-small cell lung cancer, gastrointestinal stromal tumors, and other malignancies. Its ability to induce apoptosis and inhibit tumor growth has been studied in preclinical and clinical trials, offering hope for improved therapeutic outcomes in oncology. Additionally, research explores its role in overcoming drug resistance in certain cancers, enhancing the efficacy of existing treatments.