Used in targeted cancer therapies, particularly for tumors expressing CLDN6 (Claudin-6), such as certain testicular, ovarian, and gastrointestinal cancers. Binds specifically to CLDN6 on cell surfaces, enabling precise delivery of conjugated drugs or toxins to cancer cells while sparing healthy tissues. Investigated in antibody-drug conjugates (ADCs) and chimeric antigen receptor (CAR) T-cell therapies to enhance tumor recognition and destruction. Also serves as a research tool to study CLDN6 expression and function in cellular models.