nuclear protein in testis is a 1,132 amino acid protein that is specifically expressed in testis. Belonging to the FAM22 family, NUT shuttles between nucleus and cytoplasm via a leptomycin-sensitive pathway. It is suggested that the translocation of the NUT gene is the cause of nuclear protein in testis midline carcinomas (NMC). NMCs are highly aggressive carcinomas typically arising in midline structures in young individuals. These carcinomas are characterized by the presence of a chromosomal rearrangement of the NUT gene on chromosome 15 (15q14), which results in a chromosomal translocation most commonly involving the BRD4 gene on chromosome 19p13. Endogenous BRD-NUT fusion proteins contribute to carcinogenesis by associating with chromatin and interfering with epithelial differentiation.