The BAP1 (BRCA1-associated protein 1) antibody is a critical tool in cancer research and diagnostics, targeting the BAP1 protein encoded by the *BAP1* gene on chromosome 3p21.1. BAP1 functions as a tumor suppressor, participating in chromatin remodeling, DNA damage repair, and cell cycle regulation through its deubiquitinase activity. Mutations or loss of BAP1 are strongly linked to cancer susceptibility and aggressiveness, notably in mesothelioma, uveal melanoma, renal cell carcinoma, and certain melanocytic tumors.
BAP1 immunohistochemistry (IHC) using specific antibodies helps identify BAP1 protein loss, aiding in differential diagnosis. For instance, BAP1-negative staining in mesothelial proliferations supports malignant mesothelioma over benign reactive conditions. Similarly, it distinguishes atypical Spitz tumors from malignant melanomas. The antibody's clinical utility extends to prognostic stratification, as BAP1 loss in uveal melanoma correlates with higher metastatic risk.
Research applications include studying BAP1's role in epigenetic regulation and its interaction with pathways like the BRCA1/BARD1 complex. However, interpretation requires caution, as staining patterns vary by tumor type and antibody clones. Validated BAP1 antibodies remain essential for advancing molecular oncology and personalized therapeutic strategies.