Furthermore, CCDC19-mediated inhibition of cell proliferation, migration and invasion was possibly correlated with down-regulation of E2F1, which suppressed the expression of cell division cycle 6 (CDC6), a protein regulating DNA replication, activating and maintaining the checkpoint mechanisms in the cell cycle, and further induced the expression of cell cycle inhibitor p16 and epithelial to mesenchymal transition (EMT) marker E-Cadherin in NSCLC [29,30]. Here, E2F1 is linked to non-small cell lung carcinoma.