BAP1 and mesothelioma: Additionally, BAP1, enhancer of zeste 2 Polycomb progress complex 2 subunit, and S-methyl-5’-thioadenosine phosphorylase (MTAP) loss detected by immunohistochemistry, or CDKN2A (p16) homozygous deletion by FISH is used for differentiation between benign mesothelial proliferation and mesothelioma.