Next, we stained human PDA tissue microarrays (TMAs) comprising specimens representing progression of premalignant lesions to overt cancer and metastatic disease, and stratified based on grade (well- vs. poorly differentiated, Fig. 1f), with a BAP1 antibody that was validated for immunohistochemistry (IHC) in knockout mice (Supplementary Fig. 1i). Here, BAP1 is linked to metastatic neoplasm.