BAP1 contains a UCH37-like domain (ULD) [79], binding domains for BRCA1 (BRCA1 DNA repair associated) and BARD1 (BRCA1-associated RING domain 1), which form a tumor suppressor heterodimeric complex [80], and a binding domain for host cell factor-1 (HCFC1), which interacts with histone-modifying complexes during cell division [73,79] by removing ubiquitin molecules from histone H2A [81]. Here, HCFC1 is linked to neoplasm.