ID1 and colorectal carcinoma: Although PTEN transcription is regulated by several molecules, including Egr-1 (Virolle et al, 2001), c-Jun (Hettinger et al, 2007), Id-1 (Lee et al, 2009) and TGF-β (Chow et al, 2010), little is known about the gene regulating PTEN transcription during CRC development.