In particular, experiments on oral cancer cell lines showed that suppression of CDCA2 expression with shRNA significantly inhibits cellular proliferation, by arresting cell-cycle progression at the G1 phase through activation of the DDR in vitro, thus suggesting that up-regulation of CDCA2 in tumor cells might prevent the arrest of cell-cycle progression, via decreased expression of CDKIs and regulation of the DDR. This evidence concerns the gene CDCA2 and lip and oral cavity carcinoma.