Cutaneous T-cell lymphoma-associated tumor antigen (SE20-4), also known as differentially expressed nucleolar transforming growth factor (TGF)-β1 target protein (DENTT), is a member of the TSPY/TSPY-like/SET/NAP-1 superfamily whose mRNA is overexpressed in TGF-β1-induced human lung cancer cells (Ozbun et al. 2001). The gene discussed is TSPY1; the disease is lung cancer.