TMPRSS2 and prostate carcinoma: Recently, fusions involving SKIL (which encodes a SMAD inhibitor) 3′ to androgen-regulated promoters such as TMPRSS2, SLC45A3, and ACPP, were found in 6 of 540 (1.1 %) prostate cancers and one cell line xenograft, LuCaP-77 [101].