Cyclin-D1-binding protein 1 (CCNDBP1, also known as GCIP) is a helix-loop-helix protein that may negatively regulate cell cycle progression and could function in tumour suppression []. It may act, at least in part, via inhibition of the cyclin-D1/CDK4 complex, thereby preventing phosphorylation of RB1 and blocking E2F-dependent transcription [, ].
