TMPRSS2 and Familial prostate cancer: The TMPRSS2-ERG fusion gene arising from genetic rearrangement (fusion of encoding transmembrane protease serine 2, TMPRSS2 gene, and EST-related gene, ERG) has also been a central focus in prostate cancer, which leads to aberrant expression of the ETS transcription factor ERG (Tomlins et al., 2005; Kandoth, 2013).