Used in research and drug development targeting fibroblast activation protein (FAP), which is overexpressed in tumor stroma of various cancers such as pancreatic, colorectal, and breast cancer. The His tag allows for easy purification and detection, making it valuable in studying FAP's role in tumor growth, metastasis, and immune evasion. It is also employed in screening and validating FAP-specific inhibitors and antibodies for diagnostic and therapeutic applications. Additionally, it supports the development of targeted imaging agents and cancer immunotherapies.